linux/drivers/acpi/scan.c

2288 lines
56 KiB

include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 17:04:11 +09:00
ACPI: Add new sysfs interface to export device description Add support to export the device description obtained from the ACPI _STR method, if one exists for a device, to user-space via a sysfs interface. This new interface provides a standard and platform neutral way for users to obtain the description text stored in the ACPI _STR method. If no _STR method exists for the device, no sysfs 'description' file will be created. The 'description' file will be located in the /sys/devices/ directory using the device's path. /sys/device/<bus>/<bridge path>/<device path>.../firmware_node/description Example: /sys/devices/pci0000:00/0000:00.07.0/0000:0e:00.0/firmware_node/description It can also be located using the ACPI device path, for example: /sys/devices/LNXSYSTM:00/device:00/ACPI0004:00/PNP0A08:00/device:13/device:15/description /sys/devices/LNXSYSTM:00/device:00/ACPI0004:00/ACPI0004:01/ACPI0007:02/description Execute the 'cat' command on the 'description' file to obtain the description string for that device. This patch also includes documentation describing how the new sysfs interface works Changes from v1-v2 based on comments by Len Brown and Fengguang Wu * Removed output "No Description" and leaving a NULL attribute if the _STR method failed to evaluate. * In acpi_device_remove_files() removed the redundent check of dev->pnp.str_obj before calling free. This check triggered a message from smatch. Signed-off-by: Lance Ortiz <lance.ortiz@hp.com> Signed-off-by: Len Brown <len.brown@intel.com>
2012-10-02 12:43:23 -06:00
ACPI: Add _DEP support to fix battery issue on Asus T100TA ACPI 5.0 introduces _DEP (Operation Region Dependencies) to designate device objects that OSPM should assign a higher priority in start ordering due to future operation region accesses. On Asus T100TA, ACPI battery info are read from a I2C slave device via I2C operation region. Before I2C operation region handler is installed, battery _STA always returns 0. There is a _DEP method of designating start order under battery device node. This patch is to implement _DEP feature to fix battery issue on the Asus T100TA. Introducing acpi_dep_list and adding dep_unmet count in struct acpi_device. During ACPI namespace scan, create struct acpi_dep_data for a valid pair of master (device pointed to by _DEP)/ slave(device with _DEP), record master's and slave's ACPI handle in it and put it into acpi_dep_list. The dep_unmet count will increase by one if there is a device under its _DEP. Driver's probe() should return EPROBE_DEFER when find dep_unmet is larger than 0. When I2C operation region handler is installed, remove all struct acpi_dep_data on the acpi_dep_list whose master is pointed to I2C host controller and decrease slave's dep_unmet. When dep_unmet decreases to 0, all _DEP conditions are met and then do acpi_bus_attach() for the device in order to resolve battery _STA issue on the Asus T100TA. Link: https://bugzilla.kernel.org/show_bug.cgi?id=69011 Tested-by: Jan-Michael Brummer <jan.brummer@tabos.org> Tested-by: Adam Williamson <adamw@happyassassin.net> Tested-by: Michael Shigorin <shigorin@gmail.com> Acked-by: Wolfram Sang <wsa@the-dreams.de> Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Lan Tianyu <tianyu.lan@intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-11-23 21:22:54 +08:00
ACPI: Add _DEP support to fix battery issue on Asus T100TA ACPI 5.0 introduces _DEP (Operation Region Dependencies) to designate device objects that OSPM should assign a higher priority in start ordering due to future operation region accesses. On Asus T100TA, ACPI battery info are read from a I2C slave device via I2C operation region. Before I2C operation region handler is installed, battery _STA always returns 0. There is a _DEP method of designating start order under battery device node. This patch is to implement _DEP feature to fix battery issue on the Asus T100TA. Introducing acpi_dep_list and adding dep_unmet count in struct acpi_device. During ACPI namespace scan, create struct acpi_dep_data for a valid pair of master (device pointed to by _DEP)/ slave(device with _DEP), record master's and slave's ACPI handle in it and put it into acpi_dep_list. The dep_unmet count will increase by one if there is a device under its _DEP. Driver's probe() should return EPROBE_DEFER when find dep_unmet is larger than 0. When I2C operation region handler is installed, remove all struct acpi_dep_data on the acpi_dep_list whose master is pointed to I2C host controller and decrease slave's dep_unmet. When dep_unmet decreases to 0, all _DEP conditions are met and then do acpi_bus_attach() for the device in order to resolve battery _STA issue on the Asus T100TA. Link: https://bugzilla.kernel.org/show_bug.cgi?id=69011 Tested-by: Jan-Michael Brummer <jan.brummer@tabos.org> Tested-by: Adam Williamson <adamw@happyassassin.net> Tested-by: Michael Shigorin <shigorin@gmail.com> Acked-by: Wolfram Sang <wsa@the-dreams.de> Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Lan Tianyu <tianyu.lan@intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-11-23 21:22:54 +08:00
ACPI / hotplug: Fix concurrency issues and memory leaks This changeset is aimed at fixing a few different but related problems in the ACPI hotplug infrastructure. First of all, since notify handlers may be run in parallel with acpi_bus_scan(), acpi_bus_trim() and acpi_bus_hot_remove_device() and some of them are installed for ACPI handles that have no struct acpi_device objects attached (i.e. before those objects are created), those notify handlers have to take acpi_scan_lock to prevent races from taking place (e.g. a struct acpi_device is found to be present for the given ACPI handle, but right after that it is removed by acpi_bus_trim() running in parallel to the given notify handler). Moreover, since some of them call acpi_bus_scan() and acpi_bus_trim(), this leads to the conclusion that acpi_scan_lock should be acquired by the callers of these two funtions rather by these functions themselves. For these reasons, make all notify handlers that can handle device addition and eject events take acpi_scan_lock and remove the acpi_scan_lock locking from acpi_bus_scan() and acpi_bus_trim(). Accordingly, update all of their users to make sure that they are always called under acpi_scan_lock. Furthermore, since eject operations are carried out asynchronously with respect to the notify events that trigger them, with the help of acpi_bus_hot_remove_device(), even if notify handlers take the ACPI scan lock, it still is possible that, for example, acpi_bus_trim() will run between acpi_bus_hot_remove_device() and the notify handler that scheduled its execution and that acpi_bus_trim() will remove the device node passed to acpi_bus_hot_remove_device() for ejection. In that case, the struct acpi_device object obtained by acpi_bus_hot_remove_device() will be invalid and not-so-funny things will ensue. To protect agaist that, make the users of acpi_bus_hot_remove_device() run get_device() on ACPI device node objects that are about to be passed to it and make acpi_bus_hot_remove_device() run put_device() on them and check if their ACPI handles are not NULL (make acpi_device_unregister() clear the device nodes' ACPI handles for that check to work). Finally, observe that acpi_os_hotplug_execute() actually can fail, in which case its caller ought to free memory allocated for the context object to prevent leaks from happening. It also needs to run put_device() on the device node that it ran get_device() on previously in that case. Modify the code accordingly. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Yinghai Lu <yinghai@kernel.org>
2013-02-13 14:36:47 +01:00
ACPI / hotplug / driver core: Handle containers in a special way ACPI container devices require special hotplug handling, at least on some systems, since generally user space needs to carry out system-specific cleanup before it makes sense to offline devices in the container. However, the current ACPI hotplug code for containers first attempts to offline devices in the container and only then it notifies user space of the container offline. Moreover, after commit 202317a573b2 (ACPI / scan: Add acpi_device objects for all device nodes in the namespace), ACPI device objects representing containers are present as long as the ACPI namespace nodes corresponding to them are present, which may be forever, even if the container devices are physically detached from the system (the return values of the corresponding _STA methods change in those cases, but generally the namespace nodes themselves are still there). Thus it is useful to introduce entities representing containers that will go away during container hot-unplug. The goal of this change is to address both the above issues. The idea is to create a "companion" container system device for each of the ACPI container device objects during the initial namespace scan or on a hotplug event making the container present. That system device will be unregistered on container removal. A new bus type for container devices is added for this purpose, because device offline and online operations need to be defined for them. The online operation is a trivial function that is always successful and the offline uses a callback pointed to by the container device's offline member. For ACPI containers that callback simply walks the list of ACPI device objects right below the container object (its children) and checks if all of their physical companion devices are offline. If that's not the case, it returns -EBUSY and the container system devivce cannot be put offline. Consequently, to put the container system device offline, it is necessary to put all of the physical devices depending on its ACPI companion object offline beforehand. Container system devices created for ACPI container objects are initially online. They are created by the container ACPI scan handler whose hotplug.demand_offline flag is set. That causes acpi_scan_hot_remove() to check if the companion container system device is offline before attempting to remove an ACPI container or any devices below it. If the check fails, a KOBJ_CHANGE uevent is emitted for the container system device in question and user space is expected to offline all devices below the container and the container itself in response to it. Then, user space can finalize the removal of the container with the help of its ACPI device object's eject attribute in sysfs. Tested-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-12-29 15:25:48 +01:00
ACPI / hotplug / driver core: Handle containers in a special way ACPI container devices require special hotplug handling, at least on some systems, since generally user space needs to carry out system-specific cleanup before it makes sense to offline devices in the container. However, the current ACPI hotplug code for containers first attempts to offline devices in the container and only then it notifies user space of the container offline. Moreover, after commit 202317a573b2 (ACPI / scan: Add acpi_device objects for all device nodes in the namespace), ACPI device objects representing containers are present as long as the ACPI namespace nodes corresponding to them are present, which may be forever, even if the container devices are physically detached from the system (the return values of the corresponding _STA methods change in those cases, but generally the namespace nodes themselves are still there). Thus it is useful to introduce entities representing containers that will go away during container hot-unplug. The goal of this change is to address both the above issues. The idea is to create a "companion" container system device for each of the ACPI container device objects during the initial namespace scan or on a hotplug event making the container present. That system device will be unregistered on container removal. A new bus type for container devices is added for this purpose, because device offline and online operations need to be defined for them. The online operation is a trivial function that is always successful and the offline uses a callback pointed to by the container device's offline member. For ACPI containers that callback simply walks the list of ACPI device objects right below the container object (its children) and checks if all of their physical companion devices are offline. If that's not the case, it returns -EBUSY and the container system devivce cannot be put offline. Consequently, to put the container system device offline, it is necessary to put all of the physical devices depending on its ACPI companion object offline beforehand. Container system devices created for ACPI container objects are initially online. They are created by the container ACPI scan handler whose hotplug.demand_offline flag is set. That causes acpi_scan_hot_remove() to check if the companion container system device is offline before attempting to remove an ACPI container or any devices below it. If the check fails, a KOBJ_CHANGE uevent is emitted for the container system device in question and user space is expected to offline all devices below the container and the container itself in response to it. Then, user space can finalize the removal of the container with the help of its ACPI device object's eject attribute in sysfs. Tested-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-12-29 15:25:48 +01:00
ACPI / hotplug / driver core: Handle containers in a special way ACPI container devices require special hotplug handling, at least on some systems, since generally user space needs to carry out system-specific cleanup before it makes sense to offline devices in the container. However, the current ACPI hotplug code for containers first attempts to offline devices in the container and only then it notifies user space of the container offline. Moreover, after commit 202317a573b2 (ACPI / scan: Add acpi_device objects for all device nodes in the namespace), ACPI device objects representing containers are present as long as the ACPI namespace nodes corresponding to them are present, which may be forever, even if the container devices are physically detached from the system (the return values of the corresponding _STA methods change in those cases, but generally the namespace nodes themselves are still there). Thus it is useful to introduce entities representing containers that will go away during container hot-unplug. The goal of this change is to address both the above issues. The idea is to create a "companion" container system device for each of the ACPI container device objects during the initial namespace scan or on a hotplug event making the container present. That system device will be unregistered on container removal. A new bus type for container devices is added for this purpose, because device offline and online operations need to be defined for them. The online operation is a trivial function that is always successful and the offline uses a callback pointed to by the container device's offline member. For ACPI containers that callback simply walks the list of ACPI device objects right below the container object (its children) and checks if all of their physical companion devices are offline. If that's not the case, it returns -EBUSY and the container system devivce cannot be put offline. Consequently, to put the container system device offline, it is necessary to put all of the physical devices depending on its ACPI companion object offline beforehand. Container system devices created for ACPI container objects are initially online. They are created by the container ACPI scan handler whose hotplug.demand_offline flag is set. That causes acpi_scan_hot_remove() to check if the companion container system device is offline before attempting to remove an ACPI container or any devices below it. If the check fails, a KOBJ_CHANGE uevent is emitted for the container system device in question and user space is expected to offline all devices below the container and the container itself in response to it. Then, user space can finalize the removal of the container with the help of its ACPI device object's eject attribute in sysfs. Tested-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-12-29 15:25:48 +01:00
ACPI / hotplug: Remove containers synchronously The current protocol for handling hot remove of containers is very fragile and causes acpi_eject_store() to acquire acpi_scan_lock which may deadlock with the removal of the device that it is called for (the reason is that device sysfs attributes cannot be removed while their callbacks are being executed and ACPI device objects are removed under acpi_scan_lock). The problem is related to the fact that containers are handled by acpi_bus_device_eject() in a special way, which is to emit an offline uevent instead of just removing the container. Then, user space is expected to handle that uevent and use the container's "eject" attribute to actually remove it. That is fragile, because user space may fail to complete the ejection (for example, by not using the container's "eject" attribute at all) leaving the BIOS kind of in a limbo. Moreover, if the eject event is not signaled for a container itself, but for its parent device object (or generally, for an ancestor above it in the ACPI namespace), the container will be removed straight away without doing that whole dance. For this reason, modify acpi_bus_device_eject() to remove containers synchronously like any other objects (user space will get its uevent anyway in case it does some other things in response to it) and remove the eject_pending ACPI device flag that is not used any more. This way acpi_eject_store() doesn't have a reason to acquire acpi_scan_lock any more and one possible deadlock scenario goes away (plus the code is simplified a bit). Reported-and-tested-by: Gu Zheng <guz.fnst@cn.fujitsu.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Toshi Kani <toshi.kani@hp.com>
2013-08-28 21:41:07 +02:00
ACPI / hotplug / PCI: Consolidate ACPIPHP with ACPI core hotplug The ACPI-based PCI hotplug (ACPIPHP) code currently attaches its hotplug context objects directly to ACPI namespace nodes representing hotplug devices. However, after recent changes causing struct acpi_device to be created for every namespace node representing a device (regardless of its status), that is not necessary any more. Moreover, it's vulnerable to the theoretical issue that the ACPI handle passed in the context between handle_hotplug_event() and hotplug_event_work() may become invalid in the meantime (as a result of a concurrent table unload). In principle, this issue might be addressed by adding a non-empty release handler for ACPIPHP hotplug context objects analogous to acpi_scan_drop_device(), but that would duplicate the code in that function and in acpi_device_del_work_fn(). For this reason, it's better to modify ACPIPHP to attach its device hotplug contexts to struct device objects representing hotplug devices and make it use acpi_hotplug_notify_cb() as its notify handler. At the same time, acpi_device_hotplug() can be modified to dispatch the new .hp.event() callback pointing to acpiphp_hotplug_event() from ACPI device objects associated with PCI devices or use the generic ACPI device hotplug code for device objects with matching scan handlers. This allows the existing code duplication between ACPIPHP and the ACPI core to be reduced too and makes further ACPI-based device hotplug consolidation possible. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-06 17:31:37 +01:00
ACPI / hotplug / PCI: Consolidate ACPIPHP with ACPI core hotplug The ACPI-based PCI hotplug (ACPIPHP) code currently attaches its hotplug context objects directly to ACPI namespace nodes representing hotplug devices. However, after recent changes causing struct acpi_device to be created for every namespace node representing a device (regardless of its status), that is not necessary any more. Moreover, it's vulnerable to the theoretical issue that the ACPI handle passed in the context between handle_hotplug_event() and hotplug_event_work() may become invalid in the meantime (as a result of a concurrent table unload). In principle, this issue might be addressed by adding a non-empty release handler for ACPIPHP hotplug context objects analogous to acpi_scan_drop_device(), but that would duplicate the code in that function and in acpi_device_del_work_fn(). For this reason, it's better to modify ACPIPHP to attach its device hotplug contexts to struct device objects representing hotplug devices and make it use acpi_hotplug_notify_cb() as its notify handler. At the same time, acpi_device_hotplug() can be modified to dispatch the new .hp.event() callback pointing to acpiphp_hotplug_event() from ACPI device objects associated with PCI devices or use the generic ACPI device hotplug code for device objects with matching scan handlers. This allows the existing code duplication between ACPIPHP and the ACPI core to be reduced too and makes further ACPI-based device hotplug consolidation possible. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-06 17:31:37 +01:00
ACPI / hotplug / PCI: Consolidate ACPIPHP with ACPI core hotplug The ACPI-based PCI hotplug (ACPIPHP) code currently attaches its hotplug context objects directly to ACPI namespace nodes representing hotplug devices. However, after recent changes causing struct acpi_device to be created for every namespace node representing a device (regardless of its status), that is not necessary any more. Moreover, it's vulnerable to the theoretical issue that the ACPI handle passed in the context between handle_hotplug_event() and hotplug_event_work() may become invalid in the meantime (as a result of a concurrent table unload). In principle, this issue might be addressed by adding a non-empty release handler for ACPIPHP hotplug context objects analogous to acpi_scan_drop_device(), but that would duplicate the code in that function and in acpi_device_del_work_fn(). For this reason, it's better to modify ACPIPHP to attach its device hotplug contexts to struct device objects representing hotplug devices and make it use acpi_hotplug_notify_cb() as its notify handler. At the same time, acpi_device_hotplug() can be modified to dispatch the new .hp.event() callback pointing to acpiphp_hotplug_event() from ACPI device objects associated with PCI devices or use the generic ACPI device hotplug code for device objects with matching scan handlers. This allows the existing code duplication between ACPIPHP and the ACPI core to be reduced too and makes further ACPI-based device hotplug consolidation possible. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-06 17:31:37 +01:00
ACPI / hotplug / PCI: Consolidate ACPIPHP with ACPI core hotplug The ACPI-based PCI hotplug (ACPIPHP) code currently attaches its hotplug context objects directly to ACPI namespace nodes representing hotplug devices. However, after recent changes causing struct acpi_device to be created for every namespace node representing a device (regardless of its status), that is not necessary any more. Moreover, it's vulnerable to the theoretical issue that the ACPI handle passed in the context between handle_hotplug_event() and hotplug_event_work() may become invalid in the meantime (as a result of a concurrent table unload). In principle, this issue might be addressed by adding a non-empty release handler for ACPIPHP hotplug context objects analogous to acpi_scan_drop_device(), but that would duplicate the code in that function and in acpi_device_del_work_fn(). For this reason, it's better to modify ACPIPHP to attach its device hotplug contexts to struct device objects representing hotplug devices and make it use acpi_hotplug_notify_cb() as its notify handler. At the same time, acpi_device_hotplug() can be modified to dispatch the new .hp.event() callback pointing to acpiphp_hotplug_event() from ACPI device objects associated with PCI devices or use the generic ACPI device hotplug code for device objects with matching scan handlers. This allows the existing code duplication between ACPIPHP and the ACPI core to be reduced too and makes further ACPI-based device hotplug consolidation possible. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-06 17:31:37 +01:00
ACPI / hotplug / PCI: Consolidate ACPIPHP with ACPI core hotplug The ACPI-based PCI hotplug (ACPIPHP) code currently attaches its hotplug context objects directly to ACPI namespace nodes representing hotplug devices. However, after recent changes causing struct acpi_device to be created for every namespace node representing a device (regardless of its status), that is not necessary any more. Moreover, it's vulnerable to the theoretical issue that the ACPI handle passed in the context between handle_hotplug_event() and hotplug_event_work() may become invalid in the meantime (as a result of a concurrent table unload). In principle, this issue might be addressed by adding a non-empty release handler for ACPIPHP hotplug context objects analogous to acpi_scan_drop_device(), but that would duplicate the code in that function and in acpi_device_del_work_fn(). For this reason, it's better to modify ACPIPHP to attach its device hotplug contexts to struct device objects representing hotplug devices and make it use acpi_hotplug_notify_cb() as its notify handler. At the same time, acpi_device_hotplug() can be modified to dispatch the new .hp.event() callback pointing to acpiphp_hotplug_event() from ACPI device objects associated with PCI devices or use the generic ACPI device hotplug code for device objects with matching scan handlers. This allows the existing code duplication between ACPIPHP and the ACPI core to be reduced too and makes further ACPI-based device hotplug consolidation possible. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-06 17:31:37 +01:00
ACPI / dock: Dispatch dock notifications from the global notify handler The ACPI dock station code carries out an extra namespace scan before the main one in order to find and register all of the dock device objects. Then, it registers a notify handler for each of them for handling dock events. However, dock device objects need not be scanned for upfront. They very well can be enumerated and registered during the first phase of the main namespace scan, before attaching scan handlers and ACPI drivers to ACPI device objects. Then, the dependent devices can be added to the in the second phase. That makes it possible to drop the extra namespace scan, so do it. Moreover, it is not necessary to register notify handlers for all of the dock stations' namespace nodes, becuase notifications may be dispatched from the global notify handler for them. Do that and drop two functions used for dock notify handling, acpi_dock_deferred_cb() and dock_notify_handler(), that aren't necessary any more. Finally, some dock station objects have _HID objects matching the ACPI container scan handler which causes it to claim those objects and try to handle their hotplug, but that is not a good idea, because those objects have their own special hotplug handling anyway. For this reason, the hotplug_notify flag should not be set for ACPI device objects representing dock stations and the container scan handler should be made ignore those objects, so make that happen. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-16 01:51:01 +01:00
ACPI / hotplug / PCI: Consolidate ACPIPHP with ACPI core hotplug The ACPI-based PCI hotplug (ACPIPHP) code currently attaches its hotplug context objects directly to ACPI namespace nodes representing hotplug devices. However, after recent changes causing struct acpi_device to be created for every namespace node representing a device (regardless of its status), that is not necessary any more. Moreover, it's vulnerable to the theoretical issue that the ACPI handle passed in the context between handle_hotplug_event() and hotplug_event_work() may become invalid in the meantime (as a result of a concurrent table unload). In principle, this issue might be addressed by adding a non-empty release handler for ACPIPHP hotplug context objects analogous to acpi_scan_drop_device(), but that would duplicate the code in that function and in acpi_device_del_work_fn(). For this reason, it's better to modify ACPIPHP to attach its device hotplug contexts to struct device objects representing hotplug devices and make it use acpi_hotplug_notify_cb() as its notify handler. At the same time, acpi_device_hotplug() can be modified to dispatch the new .hp.event() callback pointing to acpiphp_hotplug_event() from ACPI device objects associated with PCI devices or use the generic ACPI device hotplug code for device objects with matching scan handlers. This allows the existing code duplication between ACPIPHP and the ACPI core to be reduced too and makes further ACPI-based device hotplug consolidation possible. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-06 17:31:37 +01:00
ACPI / hotplug / PCI: Consolidate ACPIPHP with ACPI core hotplug The ACPI-based PCI hotplug (ACPIPHP) code currently attaches its hotplug context objects directly to ACPI namespace nodes representing hotplug devices. However, after recent changes causing struct acpi_device to be created for every namespace node representing a device (regardless of its status), that is not necessary any more. Moreover, it's vulnerable to the theoretical issue that the ACPI handle passed in the context between handle_hotplug_event() and hotplug_event_work() may become invalid in the meantime (as a result of a concurrent table unload). In principle, this issue might be addressed by adding a non-empty release handler for ACPIPHP hotplug context objects analogous to acpi_scan_drop_device(), but that would duplicate the code in that function and in acpi_device_del_work_fn(). For this reason, it's better to modify ACPIPHP to attach its device hotplug contexts to struct device objects representing hotplug devices and make it use acpi_hotplug_notify_cb() as its notify handler. At the same time, acpi_device_hotplug() can be modified to dispatch the new .hp.event() callback pointing to acpiphp_hotplug_event() from ACPI device objects associated with PCI devices or use the generic ACPI device hotplug code for device objects with matching scan handlers. This allows the existing code duplication between ACPIPHP and the ACPI core to be reduced too and makes further ACPI-based device hotplug consolidation possible. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-06 17:31:37 +01:00
ACPI / hotplug / PCI: Consolidate ACPIPHP with ACPI core hotplug The ACPI-based PCI hotplug (ACPIPHP) code currently attaches its hotplug context objects directly to ACPI namespace nodes representing hotplug devices. However, after recent changes causing struct acpi_device to be created for every namespace node representing a device (regardless of its status), that is not necessary any more. Moreover, it's vulnerable to the theoretical issue that the ACPI handle passed in the context between handle_hotplug_event() and hotplug_event_work() may become invalid in the meantime (as a result of a concurrent table unload). In principle, this issue might be addressed by adding a non-empty release handler for ACPIPHP hotplug context objects analogous to acpi_scan_drop_device(), but that would duplicate the code in that function and in acpi_device_del_work_fn(). For this reason, it's better to modify ACPIPHP to attach its device hotplug contexts to struct device objects representing hotplug devices and make it use acpi_hotplug_notify_cb() as its notify handler. At the same time, acpi_device_hotplug() can be modified to dispatch the new .hp.event() callback pointing to acpiphp_hotplug_event() from ACPI device objects associated with PCI devices or use the generic ACPI device hotplug code for device objects with matching scan handlers. This allows the existing code duplication between ACPIPHP and the ACPI core to be reduced too and makes further ACPI-based device hotplug consolidation possible. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-06 17:31:37 +01:00
ACPI / hotplug / PCI: Consolidate ACPIPHP with ACPI core hotplug The ACPI-based PCI hotplug (ACPIPHP) code currently attaches its hotplug context objects directly to ACPI namespace nodes representing hotplug devices. However, after recent changes causing struct acpi_device to be created for every namespace node representing a device (regardless of its status), that is not necessary any more. Moreover, it's vulnerable to the theoretical issue that the ACPI handle passed in the context between handle_hotplug_event() and hotplug_event_work() may become invalid in the meantime (as a result of a concurrent table unload). In principle, this issue might be addressed by adding a non-empty release handler for ACPIPHP hotplug context objects analogous to acpi_scan_drop_device(), but that would duplicate the code in that function and in acpi_device_del_work_fn(). For this reason, it's better to modify ACPIPHP to attach its device hotplug contexts to struct device objects representing hotplug devices and make it use acpi_hotplug_notify_cb() as its notify handler. At the same time, acpi_device_hotplug() can be modified to dispatch the new .hp.event() callback pointing to acpiphp_hotplug_event() from ACPI device objects associated with PCI devices or use the generic ACPI device hotplug code for device objects with matching scan handlers. This allows the existing code duplication between ACPIPHP and the ACPI core to be reduced too and makes further ACPI-based device hotplug consolidation possible. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-06 17:31:37 +01:00
ACPI / hotplug / PCI: Consolidate ACPIPHP with ACPI core hotplug The ACPI-based PCI hotplug (ACPIPHP) code currently attaches its hotplug context objects directly to ACPI namespace nodes representing hotplug devices. However, after recent changes causing struct acpi_device to be created for every namespace node representing a device (regardless of its status), that is not necessary any more. Moreover, it's vulnerable to the theoretical issue that the ACPI handle passed in the context between handle_hotplug_event() and hotplug_event_work() may become invalid in the meantime (as a result of a concurrent table unload). In principle, this issue might be addressed by adding a non-empty release handler for ACPIPHP hotplug context objects analogous to acpi_scan_drop_device(), but that would duplicate the code in that function and in acpi_device_del_work_fn(). For this reason, it's better to modify ACPIPHP to attach its device hotplug contexts to struct device objects representing hotplug devices and make it use acpi_hotplug_notify_cb() as its notify handler. At the same time, acpi_device_hotplug() can be modified to dispatch the new .hp.event() callback pointing to acpiphp_hotplug_event() from ACPI device objects associated with PCI devices or use the generic ACPI device hotplug code for device objects with matching scan handlers. This allows the existing code duplication between ACPIPHP and the ACPI core to be reduced too and makes further ACPI-based device hotplug consolidation possible. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-06 17:31:37 +01:00
ACPI / hotplug / PCI: Consolidate ACPIPHP with ACPI core hotplug The ACPI-based PCI hotplug (ACPIPHP) code currently attaches its hotplug context objects directly to ACPI namespace nodes representing hotplug devices. However, after recent changes causing struct acpi_device to be created for every namespace node representing a device (regardless of its status), that is not necessary any more. Moreover, it's vulnerable to the theoretical issue that the ACPI handle passed in the context between handle_hotplug_event() and hotplug_event_work() may become invalid in the meantime (as a result of a concurrent table unload). In principle, this issue might be addressed by adding a non-empty release handler for ACPIPHP hotplug context objects analogous to acpi_scan_drop_device(), but that would duplicate the code in that function and in acpi_device_del_work_fn(). For this reason, it's better to modify ACPIPHP to attach its device hotplug contexts to struct device objects representing hotplug devices and make it use acpi_hotplug_notify_cb() as its notify handler. At the same time, acpi_device_hotplug() can be modified to dispatch the new .hp.event() callback pointing to acpiphp_hotplug_event() from ACPI device objects associated with PCI devices or use the generic ACPI device hotplug code for device objects with matching scan handlers. This allows the existing code duplication between ACPIPHP and the ACPI core to be reduced too and makes further ACPI-based device hotplug consolidation possible. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-06 17:31:37 +01:00
ACPI / hotplug: Fix potential race in acpi_bus_notify() There is a slight possibility for the ACPI device object pointed to by adev in acpi_hotplug_notify_cb() to become invalid between the acpi_bus_get_device() that it comes from and the subsequent dereference of that pointer under get_device(). Namely, if acpi_scan_drop_device() runs in parallel with acpi_hotplug_notify_cb(), acpi_device_del_work_fn() queued up by it may delete the device object in question right after a successful execution of acpi_bus_get_device() in acpi_bus_notify(). An analogous problem is present in acpi_bus_notify() where the device pointer coming from acpi_bus_get_device() may become invalid before it subsequent dereference in the "if" block. To prevent that from happening, introduce a new function, acpi_bus_get_acpi_device(), working analogously to acpi_bus_get_device() except that it will grab a reference to the ACPI device object returned by it and it will do that under the ACPICA's namespace mutex. Then, make both acpi_hotplug_notify_cb() and acpi_bus_notify() use acpi_bus_get_acpi_device() instead of acpi_bus_get_device() so as to ensure that the pointers used by them will not become stale at one point. In addition to that, introduce acpi_bus_put_acpi_device() as a wrapper around put_device() to be used along with acpi_bus_get_acpi_device() and make the (new) users of the latter use acpi_bus_put_acpi_device() too. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2014-02-04 00:43:05 +01:00
ACPI / PM: Fix PM initialization for devices that are not present If an ACPI device object whose _STA returns 0 (not present and not functional) has _PR0 or _PS0, its power_manageable flag will be set and acpi_bus_init_power() will return 0 for it. Consequently, if such a device object is passed to the ACPI device PM functions, they will attempt to carry out the requested operation on the device, although they should not do that for devices that are not present. To fix that problem make acpi_bus_init_power() return an error code for devices that are not present which will cause power_manageable to be cleared for them as appropriate in acpi_bus_get_power_flags(). However, the lists of power resources should not be freed for the device in that case, so modify acpi_bus_get_power_flags() to keep those lists even if acpi_bus_init_power() returns an error. Accordingly, when deciding whether or not the lists of power resources need to be freed, acpi_free_power_resources_lists() should check the power.flags.power_resources flag instead of flags.power_manageable, so make that change too. Furthermore, if acpi_bus_attach() sees that flags.initialized is unset for the given device, it should reset the power management settings of the device and re-initialize them from scratch instead of relying on the previous settings (the device may have appeared after being not present previously, for example), so make it use the 'valid' flag of the D0 power state as the initial value of flags.power_manageable for it and call acpi_bus_init_power() to discover its current power state. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Cc: 3.10+ <stable@vger.kernel.org> # 3.10+
2015-01-01 23:38:28 +01:00
ACPI: Add support for device specific properties Device Tree is used in many embedded systems to describe the system configuration to the OS. It supports attaching properties or name-value pairs to the devices it describe. With these properties one can pass additional information to the drivers that would not be available otherwise. ACPI is another configuration mechanism (among other things) typically seen, but not limited to, x86 machines. ACPI allows passing arbitrary data from methods but there has not been mechanism equivalent to Device Tree until the introduction of _DSD in the recent publication of the ACPI 5.1 specification. In order to facilitate ACPI usage in systems where Device Tree is typically used, it would be beneficial to standardize a way to retrieve Device Tree style properties from ACPI devices, which is what we do in this patch. If a given device described in ACPI namespace wants to export properties it must implement _DSD method (Device Specific Data, introduced with ACPI 5.1) that returns the properties in a package of packages. For example: Name (_DSD, Package () { ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"), Package () { Package () {"name1", <VALUE1>}, Package () {"name2", <VALUE2>}, ... } }) The UUID reserved for properties is daffd814-6eba-4d8c-8a91-bc9bbf4aa301 and is documented in the ACPI 5.1 companion document called "_DSD Implementation Guide" [1], [2]. We add several helper functions that can be used to extract these properties and convert them to different Linux data types. The ultimate goal is that we only have one device property API that retrieves the requested properties from Device Tree or from ACPI transparent to the caller. [1] http://www.uefi.org/sites/default/files/resources/_DSD-implementation-guide-toplevel.htm [2] http://www.uefi.org/sites/default/files/resources/_DSD-device-properties-UUID.pdf Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org> Reviewed-by: Josh Triplett <josh@joshtriplett.org> Reviewed-by: Grant Likely <grant.likely@linaro.org> Signed-off-by: Darren Hart <dvhart@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-10-21 13:33:55 +02:00
ACPI / hotplug: Fix potential race in acpi_bus_notify() There is a slight possibility for the ACPI device object pointed to by adev in acpi_hotplug_notify_cb() to become invalid between the acpi_bus_get_device() that it comes from and the subsequent dereference of that pointer under get_device(). Namely, if acpi_scan_drop_device() runs in parallel with acpi_hotplug_notify_cb(), acpi_device_del_work_fn() queued up by it may delete the device object in question right after a successful execution of acpi_bus_get_device() in acpi_bus_notify(). An analogous problem is present in acpi_bus_notify() where the device pointer coming from acpi_bus_get_device() may become invalid before it subsequent dereference in the "if" block. To prevent that from happening, introduce a new function, acpi_bus_get_acpi_device(), working analogously to acpi_bus_get_device() except that it will grab a reference to the ACPI device object returned by it and it will do that under the ACPICA's namespace mutex. Then, make both acpi_hotplug_notify_cb() and acpi_bus_notify() use acpi_bus_get_acpi_device() instead of acpi_bus_get_device() so as to ensure that the pointers used by them will not become stale at one point. In addition to that, introduce acpi_bus_put_acpi_device() as a wrapper around put_device() to be used along with acpi_bus_get_acpi_device() and make the (new) users of the latter use acpi_bus_put_acpi_device() too. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2014-02-04 00:43:05 +01:00
ACPI / hotplug: Fix potential race in acpi_bus_notify() There is a slight possibility for the ACPI device object pointed to by adev in acpi_hotplug_notify_cb() to become invalid between the acpi_bus_get_device() that it comes from and the subsequent dereference of that pointer under get_device(). Namely, if acpi_scan_drop_device() runs in parallel with acpi_hotplug_notify_cb(), acpi_device_del_work_fn() queued up by it may delete the device object in question right after a successful execution of acpi_bus_get_device() in acpi_bus_notify(). An analogous problem is present in acpi_bus_notify() where the device pointer coming from acpi_bus_get_device() may become invalid before it subsequent dereference in the "if" block. To prevent that from happening, introduce a new function, acpi_bus_get_acpi_device(), working analogously to acpi_bus_get_device() except that it will grab a reference to the ACPI device object returned by it and it will do that under the ACPICA's namespace mutex. Then, make both acpi_hotplug_notify_cb() and acpi_bus_notify() use acpi_bus_get_acpi_device() instead of acpi_bus_get_device() so as to ensure that the pointers used by them will not become stale at one point. In addition to that, introduce acpi_bus_put_acpi_device() as a wrapper around put_device() to be used along with acpi_bus_get_acpi_device() and make the (new) users of the latter use acpi_bus_put_acpi_device() too. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2014-02-04 00:43:05 +01:00
ACPI / hotplug: Fix potential race in acpi_bus_notify() There is a slight possibility for the ACPI device object pointed to by adev in acpi_hotplug_notify_cb() to become invalid between the acpi_bus_get_device() that it comes from and the subsequent dereference of that pointer under get_device(). Namely, if acpi_scan_drop_device() runs in parallel with acpi_hotplug_notify_cb(), acpi_device_del_work_fn() queued up by it may delete the device object in question right after a successful execution of acpi_bus_get_device() in acpi_bus_notify(). An analogous problem is present in acpi_bus_notify() where the device pointer coming from acpi_bus_get_device() may become invalid before it subsequent dereference in the "if" block. To prevent that from happening, introduce a new function, acpi_bus_get_acpi_device(), working analogously to acpi_bus_get_device() except that it will grab a reference to the ACPI device object returned by it and it will do that under the ACPICA's namespace mutex. Then, make both acpi_hotplug_notify_cb() and acpi_bus_notify() use acpi_bus_get_acpi_device() instead of acpi_bus_get_device() so as to ensure that the pointers used by them will not become stale at one point. In addition to that, introduce acpi_bus_put_acpi_device() as a wrapper around put_device() to be used along with acpi_bus_get_acpi_device() and make the (new) users of the latter use acpi_bus_put_acpi_device() too. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2014-02-04 00:43:05 +01:00
ACPI / hotplug: Fix potential race in acpi_bus_notify() There is a slight possibility for the ACPI device object pointed to by adev in acpi_hotplug_notify_cb() to become invalid between the acpi_bus_get_device() that it comes from and the subsequent dereference of that pointer under get_device(). Namely, if acpi_scan_drop_device() runs in parallel with acpi_hotplug_notify_cb(), acpi_device_del_work_fn() queued up by it may delete the device object in question right after a successful execution of acpi_bus_get_device() in acpi_bus_notify(). An analogous problem is present in acpi_bus_notify() where the device pointer coming from acpi_bus_get_device() may become invalid before it subsequent dereference in the "if" block. To prevent that from happening, introduce a new function, acpi_bus_get_acpi_device(), working analogously to acpi_bus_get_device() except that it will grab a reference to the ACPI device object returned by it and it will do that under the ACPICA's namespace mutex. Then, make both acpi_hotplug_notify_cb() and acpi_bus_notify() use acpi_bus_get_acpi_device() instead of acpi_bus_get_device() so as to ensure that the pointers used by them will not become stale at one point. In addition to that, introduce acpi_bus_put_acpi_device() as a wrapper around put_device() to be used along with acpi_bus_get_acpi_device() and make the (new) users of the latter use acpi_bus_put_acpi_device() too. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2014-02-04 00:43:05 +01:00
ACPI / PM: Take unusual configurations of power resources into account Commit d2e5f0c (ACPI / PCI: Rework the setup and cleanup of device wakeup) moved the initial disabling of system wakeup for PCI devices into a place where it can actually work and that exposed a hidden old issue with crap^Wunusual system designs where the same power resources are used for both wakeup power and device power control at run time. Namely, say there is one power resource such that the ACPI power state D0 of a PCI device depends on that power resource (i.e. the device is in D0 when that power resource is "on") and it is used as a wakeup power resource for the same device. Then, calling acpi_pci_sleep_wake(pci_dev, false) for the device in question will cause the reference counter of that power resource to drop to 0, which in turn will cause it to be turned off. As a result, the device will go into D3cold at that point, although it should have stayed in D0. As it turns out, that happens to USB controllers on some laptops and USB becomes unusable on those machines as a result, which is a major regression from v3.8. To fix this problem, (1) increment the reference counters of wakup power resources during their initialization if they are "on" initially, (2) prevent acpi_disable_wakeup_device_power() from decrementing the reference counters of wakeup power resources that were not enabled for wakeup power previously, and (3) prevent acpi_enable_wakeup_device_power() from incrementing the reference counters of wakeup power resources that already are enabled for wakeup power. In addition to that, if it is impossible to determine the initial states of wakeup power resources, avoid enabling wakeup for devices whose wakeup power depends on those power resources. Reported-by: Dave Jones <davej@redhat.com> Reported-by: Fabio Baltieri <fabio.baltieri@linaro.org> Tested-by: Fabio Baltieri <fabio.baltieri@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-02-23 23:15:21 +01:00
ACPI / ACPICA: Do not execute _PRW methods during initialization Currently, during initialization ACPICA walks the entire ACPI namespace in search of any device objects with assciated _PRW methods. All of the _PRW methods found are executed in the process to extract the GPE information returned by them, so that the GPEs in question can be marked as "able to wakeup" (more precisely, the ACPI_GPE_CAN_WAKE flag is set for them). The only purpose of this exercise is to avoid enabling the CAN_WAKE GPEs automatically, even if there are _Lxx/_Exx methods associated with them. However, it is both costly and unnecessary, because the host OS has to execute the _PRW methods anyway to check which devices can wake up the system from sleep states. Moreover, it then uses full information returned by _PRW, including the GPE information, so it can take care of disabling the GPEs if necessary. Remove the code that walks the namespace and executes _PRW from ACPICA and modify comments to reflect that change. Make acpi_bus_set_run_wake_flags() disable GPEs for wakeup devices so that they don't cause spurious wakeup events to be signaled. This not only reduces the complexity of the ACPICA initialization code, but in some cases it should reduce the kernel boot time as well. Unfortunately, for this purpose we need a new ACPICA function, acpi_gpe_can_wake(), to be called by the host OS in order to disable the GPEs that can wake up the system and were previously enabled by acpi_ev_initialize_gpe_block() or acpi_ev_update_gpes() (such a GPE should be disabled only once, because the initialization code enables it only once, but it may be pointed to by _PRW for multiple devices and that's why the additional function is necessary). Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by: Len Brown <len.brown@intel.com>
2010-07-08 00:43:36 +02:00
ACPI / PM: Rework device power management to follow ACPI 6 The ACPI 6 specification has made some changes in the device power management area. In particular: * The D3hot power state is now supposed to be always available (instead of D3cold) and D3cold is only regarded as valid if the _PR3 object is present for the given device. * The required ordering of transitions into power states deeper than D0 is now such that for a transition into state Dx the _PSx method is supposed to be executed first, if present, and the states of the power resources the device depends on are supposed to be changed after that. * It is now explicitly forbidden to transition devices from lower-power (deeper) into higher-power (shallower) power states other than D0. Those changes have been made so the specification reflects the Windows' device power management code that the vast majority of systems using ACPI is validated against. To avoid artificial differences in ACPI device power management between Windows and Linux, modify the ACPI device power management code to follow the new specification. Add comments explaining the code flow in some unclear places. This only may affect some real corner cases in which the OS behavior expected by the firmware is different from the Windows one, but that's quite unlikely. The transition ordering change affects transitions to D1 and D2 which are rarely used (if at all) and into D3hot and D3cold for devices actually having _PR3, but those are likely to be validated against Windows anyway. The other changes may affect code calling acpi_device_get_power() or acpi_device_update_power() where ACPI_STATE_D3_HOT may be returned instead of ACPI_STATE_D3_COLD (that's why the ACPI fan driver needs to be updated too) and since transitions into ACPI_STATE_D3_HOT may remove power now, it is better to avoid this one in acpi_pm_device_sleep_state() if the "no power off" PM QoS flag is set. The only existing user of acpi_device_can_poweroff() really cares about the case when _PR3 is present, so the change in that function should not cause any problems to happen too. A plus is that PCI_D3hot can be mapped to ACPI_STATE_D3_HOT now and the compatibility with older systems should be covered automatically. In any case, if any real problems result from this, it still will be better to follow the Windows' behavior (which now is reflected by the specification too) in general and handle the cases when it doesn't work via quirks. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-05-16 01:55:35 +02:00
ACPI / PM: Rework device power management to follow ACPI 6 The ACPI 6 specification has made some changes in the device power management area. In particular: * The D3hot power state is now supposed to be always available (instead of D3cold) and D3cold is only regarded as valid if the _PR3 object is present for the given device. * The required ordering of transitions into power states deeper than D0 is now such that for a transition into state Dx the _PSx method is supposed to be executed first, if present, and the states of the power resources the device depends on are supposed to be changed after that. * It is now explicitly forbidden to transition devices from lower-power (deeper) into higher-power (shallower) power states other than D0. Those changes have been made so the specification reflects the Windows' device power management code that the vast majority of systems using ACPI is validated against. To avoid artificial differences in ACPI device power management between Windows and Linux, modify the ACPI device power management code to follow the new specification. Add comments explaining the code flow in some unclear places. This only may affect some real corner cases in which the OS behavior expected by the firmware is different from the Windows one, but that's quite unlikely. The transition ordering change affects transitions to D1 and D2 which are rarely used (if at all) and into D3hot and D3cold for devices actually having _PR3, but those are likely to be validated against Windows anyway. The other changes may affect code calling acpi_device_get_power() or acpi_device_update_power() where ACPI_STATE_D3_HOT may be returned instead of ACPI_STATE_D3_COLD (that's why the ACPI fan driver needs to be updated too) and since transitions into ACPI_STATE_D3_HOT may remove power now, it is better to avoid this one in acpi_pm_device_sleep_state() if the "no power off" PM QoS flag is set. The only existing user of acpi_device_can_poweroff() really cares about the case when _PR3 is present, so the change in that function should not cause any problems to happen too. A plus is that PCI_D3hot can be mapped to ACPI_STATE_D3_HOT now and the compatibility with older systems should be covered automatically. In any case, if any real problems result from this, it still will be better to follow the Windows' behavior (which now is reflected by the specification too) in general and handle the cases when it doesn't work via quirks. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-05-16 01:55:35 +02:00
ACPI / PM: Rework device power management to follow ACPI 6 The ACPI 6 specification has made some changes in the device power management area. In particular: * The D3hot power state is now supposed to be always available (instead of D3cold) and D3cold is only regarded as valid if the _PR3 object is present for the given device. * The required ordering of transitions into power states deeper than D0 is now such that for a transition into state Dx the _PSx method is supposed to be executed first, if present, and the states of the power resources the device depends on are supposed to be changed after that. * It is now explicitly forbidden to transition devices from lower-power (deeper) into higher-power (shallower) power states other than D0. Those changes have been made so the specification reflects the Windows' device power management code that the vast majority of systems using ACPI is validated against. To avoid artificial differences in ACPI device power management between Windows and Linux, modify the ACPI device power management code to follow the new specification. Add comments explaining the code flow in some unclear places. This only may affect some real corner cases in which the OS behavior expected by the firmware is different from the Windows one, but that's quite unlikely. The transition ordering change affects transitions to D1 and D2 which are rarely used (if at all) and into D3hot and D3cold for devices actually having _PR3, but those are likely to be validated against Windows anyway. The other changes may affect code calling acpi_device_get_power() or acpi_device_update_power() where ACPI_STATE_D3_HOT may be returned instead of ACPI_STATE_D3_COLD (that's why the ACPI fan driver needs to be updated too) and since transitions into ACPI_STATE_D3_HOT may remove power now, it is better to avoid this one in acpi_pm_device_sleep_state() if the "no power off" PM QoS flag is set. The only existing user of acpi_device_can_poweroff() really cares about the case when _PR3 is present, so the change in that function should not cause any problems to happen too. A plus is that PCI_D3hot can be mapped to ACPI_STATE_D3_HOT now and the compatibility with older systems should be covered automatically. In any case, if any real problems result from this, it still will be better to follow the Windows' behavior (which now is reflected by the specification too) in general and handle the cases when it doesn't work via quirks. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-05-16 01:55:35 +02:00
ACPI / PM: Rework device power management to follow ACPI 6 The ACPI 6 specification has made some changes in the device power management area. In particular: * The D3hot power state is now supposed to be always available (instead of D3cold) and D3cold is only regarded as valid if the _PR3 object is present for the given device. * The required ordering of transitions into power states deeper than D0 is now such that for a transition into state Dx the _PSx method is supposed to be executed first, if present, and the states of the power resources the device depends on are supposed to be changed after that. * It is now explicitly forbidden to transition devices from lower-power (deeper) into higher-power (shallower) power states other than D0. Those changes have been made so the specification reflects the Windows' device power management code that the vast majority of systems using ACPI is validated against. To avoid artificial differences in ACPI device power management between Windows and Linux, modify the ACPI device power management code to follow the new specification. Add comments explaining the code flow in some unclear places. This only may affect some real corner cases in which the OS behavior expected by the firmware is different from the Windows one, but that's quite unlikely. The transition ordering change affects transitions to D1 and D2 which are rarely used (if at all) and into D3hot and D3cold for devices actually having _PR3, but those are likely to be validated against Windows anyway. The other changes may affect code calling acpi_device_get_power() or acpi_device_update_power() where ACPI_STATE_D3_HOT may be returned instead of ACPI_STATE_D3_COLD (that's why the ACPI fan driver needs to be updated too) and since transitions into ACPI_STATE_D3_HOT may remove power now, it is better to avoid this one in acpi_pm_device_sleep_state() if the "no power off" PM QoS flag is set. The only existing user of acpi_device_can_poweroff() really cares about the case when _PR3 is present, so the change in that function should not cause any problems to happen too. A plus is that PCI_D3hot can be mapped to ACPI_STATE_D3_HOT now and the compatibility with older systems should be covered automatically. In any case, if any real problems result from this, it still will be better to follow the Windows' behavior (which now is reflected by the specification too) in general and handle the cases when it doesn't work via quirks. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-05-16 01:55:35 +02:00
ACPI / PM: Fix PM initialization for devices that are not present If an ACPI device object whose _STA returns 0 (not present and not functional) has _PR0 or _PS0, its power_manageable flag will be set and acpi_bus_init_power() will return 0 for it. Consequently, if such a device object is passed to the ACPI device PM functions, they will attempt to carry out the requested operation on the device, although they should not do that for devices that are not present. To fix that problem make acpi_bus_init_power() return an error code for devices that are not present which will cause power_manageable to be cleared for them as appropriate in acpi_bus_get_power_flags(). However, the lists of power resources should not be freed for the device in that case, so modify acpi_bus_get_power_flags() to keep those lists even if acpi_bus_init_power() returns an error. Accordingly, when deciding whether or not the lists of power resources need to be freed, acpi_free_power_resources_lists() should check the power.flags.power_resources flag instead of flags.power_manageable, so make that change too. Furthermore, if acpi_bus_attach() sees that flags.initialized is unset for the given device, it should reset the power management settings of the device and re-initialize them from scratch instead of relying on the previous settings (the device may have appeared after being not present previously, for example), so make it use the 'valid' flag of the D0 power state as the initial value of flags.power_manageable for it and call acpi_bus_init_power() to discover its current power state. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Cc: 3.10+ <stable@vger.kernel.org> # 3.10+
2015-01-01 23:38:28 +01:00
ACPI / EC: Fix regression related to PM ops support in ECDT device commit a64a62ce9a380213dc9e192f762266d70c9b40ec upstream. On platforms (ASUS X550ZE and possibly all ASUS X series) with valid ECDT EC but invalid DSDT EC, EC PM ops won't be invoked as ECDT EC is not an ACPI device. Thus the following commit actually removed post-resume acpi_ec_enable_event() invocation for such platforms, and triggered a regression on them that after being resumed, EC (actually should be ECDT) driver stops handling EC events: Commit: c2b46d679b30c5c0d7eb47a21085943242bdd8dc Subject: ACPI / EC: Add PM operations to improve event handling for resume process Notice that the root cause actually is "ECDT is not an ACPI device" rather than "the timing of acpi_ec_enable_event() invocation", this patch fixes this issue by enumerating ECDT EC as an ACPI device. Due to the existence of the noirq stage, the ability of tuning the timing of acpi_ec_enable_event() invocation is still meaningful. This patch is a little bit different from the posted fix by moving acpi_config_boot_ec() from acpi_ec_ecdt_start() to acpi_ec_add() to make sure that EC event handling won't be stopped as long as the ACPI EC driver is bound. Thus the following sequence shouldn't disable EC event handling: unbind,suspend,resume,bind. Fixes: c2b46d679b30 (ACPI / EC: Add PM operations to improve event handling for resume process) Link: https://bugzilla.kernel.org/show_bug.cgi?id=196847 Reported-by: Luya Tshimbalanga <luya@fedoraproject.org> Tested-by: Luya Tshimbalanga <luya@fedoraproject.org> Signed-off-by: Lv Zheng <lv.zheng@intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-09-26 16:54:09 +08:00
ACPI / dock: Dispatch dock notifications from the global notify handler The ACPI dock station code carries out an extra namespace scan before the main one in order to find and register all of the dock device objects. Then, it registers a notify handler for each of them for handling dock events. However, dock device objects need not be scanned for upfront. They very well can be enumerated and registered during the first phase of the main namespace scan, before attaching scan handlers and ACPI drivers to ACPI device objects. Then, the dependent devices can be added to the in the second phase. That makes it possible to drop the extra namespace scan, so do it. Moreover, it is not necessary to register notify handlers for all of the dock stations' namespace nodes, becuase notifications may be dispatched from the global notify handler for them. Do that and drop two functions used for dock notify handling, acpi_dock_deferred_cb() and dock_notify_handler(), that aren't necessary any more. Finally, some dock station objects have _HID objects matching the ACPI container scan handler which causes it to claim those objects and try to handle their hotplug, but that is not a good idea, because those objects have their own special hotplug handling anyway. For this reason, the hotplug_notify flag should not be set for ACPI device objects representing dock stations and the container scan handler should be made ignore those objects, so make that happen. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-16 01:51:01 +01:00
ACPI / dock: Dispatch dock notifications from the global notify handler The ACPI dock station code carries out an extra namespace scan before the main one in order to find and register all of the dock device objects. Then, it registers a notify handler for each of them for handling dock events. However, dock device objects need not be scanned for upfront. They very well can be enumerated and registered during the first phase of the main namespace scan, before attaching scan handlers and ACPI drivers to ACPI device objects. Then, the dependent devices can be added to the in the second phase. That makes it possible to drop the extra namespace scan, so do it. Moreover, it is not necessary to register notify handlers for all of the dock stations' namespace nodes, becuase notifications may be dispatched from the global notify handler for them. Do that and drop two functions used for dock notify handling, acpi_dock_deferred_cb() and dock_notify_handler(), that aren't necessary any more. Finally, some dock station objects have _HID objects matching the ACPI container scan handler which causes it to claim those objects and try to handle their hotplug, but that is not a good idea, because those objects have their own special hotplug handling anyway. For this reason, the hotplug_notify flag should not be set for ACPI device objects representing dock stations and the container scan handler should be made ignore those objects, so make that happen. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-16 01:51:01 +01:00
ACPI / dock: Dispatch dock notifications from the global notify handler The ACPI dock station code carries out an extra namespace scan before the main one in order to find and register all of the dock device objects. Then, it registers a notify handler for each of them for handling dock events. However, dock device objects need not be scanned for upfront. They very well can be enumerated and registered during the first phase of the main namespace scan, before attaching scan handlers and ACPI drivers to ACPI device objects. Then, the dependent devices can be added to the in the second phase. That makes it possible to drop the extra namespace scan, so do it. Moreover, it is not necessary to register notify handlers for all of the dock stations' namespace nodes, becuase notifications may be dispatched from the global notify handler for them. Do that and drop two functions used for dock notify handling, acpi_dock_deferred_cb() and dock_notify_handler(), that aren't necessary any more. Finally, some dock station objects have _HID objects matching the ACPI container scan handler which causes it to claim those objects and try to handle their hotplug, but that is not a good idea, because those objects have their own special hotplug handling anyway. For this reason, the hotplug_notify flag should not be set for ACPI device objects representing dock stations and the container scan handler should be made ignore those objects, so make that happen. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-16 01:51:01 +01:00
ACPI / dock: Dispatch dock notifications from the global notify handler The ACPI dock station code carries out an extra namespace scan before the main one in order to find and register all of the dock device objects. Then, it registers a notify handler for each of them for handling dock events. However, dock device objects need not be scanned for upfront. They very well can be enumerated and registered during the first phase of the main namespace scan, before attaching scan handlers and ACPI drivers to ACPI device objects. Then, the dependent devices can be added to the in the second phase. That makes it possible to drop the extra namespace scan, so do it. Moreover, it is not necessary to register notify handlers for all of the dock stations' namespace nodes, becuase notifications may be dispatched from the global notify handler for them. Do that and drop two functions used for dock notify handling, acpi_dock_deferred_cb() and dock_notify_handler(), that aren't necessary any more. Finally, some dock station objects have _HID objects matching the ACPI container scan handler which causes it to claim those objects and try to handle their hotplug, but that is not a good idea, because those objects have their own special hotplug handling anyway. For this reason, the hotplug_notify flag should not be set for ACPI device objects representing dock stations and the container scan handler should be made ignore those objects, so make that happen. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-16 01:51:01 +01:00
ACPI / dock: Dispatch dock notifications from the global notify handler The ACPI dock station code carries out an extra namespace scan before the main one in order to find and register all of the dock device objects. Then, it registers a notify handler for each of them for handling dock events. However, dock device objects need not be scanned for upfront. They very well can be enumerated and registered during the first phase of the main namespace scan, before attaching scan handlers and ACPI drivers to ACPI device objects. Then, the dependent devices can be added to the in the second phase. That makes it possible to drop the extra namespace scan, so do it. Moreover, it is not necessary to register notify handlers for all of the dock stations' namespace nodes, becuase notifications may be dispatched from the global notify handler for them. Do that and drop two functions used for dock notify handling, acpi_dock_deferred_cb() and dock_notify_handler(), that aren't necessary any more. Finally, some dock station objects have _HID objects matching the ACPI container scan handler which causes it to claim those objects and try to handle their hotplug, but that is not a good idea, because those objects have their own special hotplug handling anyway. For this reason, the hotplug_notify flag should not be set for ACPI device objects representing dock stations and the container scan handler should be made ignore those objects, so make that happen. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-16 01:51:01 +01:00
ACPI / dock: Dispatch dock notifications from the global notify handler The ACPI dock station code carries out an extra namespace scan before the main one in order to find and register all of the dock device objects. Then, it registers a notify handler for each of them for handling dock events. However, dock device objects need not be scanned for upfront. They very well can be enumerated and registered during the first phase of the main namespace scan, before attaching scan handlers and ACPI drivers to ACPI device objects. Then, the dependent devices can be added to the in the second phase. That makes it possible to drop the extra namespace scan, so do it. Moreover, it is not necessary to register notify handlers for all of the dock stations' namespace nodes, becuase notifications may be dispatched from the global notify handler for them. Do that and drop two functions used for dock notify handling, acpi_dock_deferred_cb() and dock_notify_handler(), that aren't necessary any more. Finally, some dock station objects have _HID objects matching the ACPI container scan handler which causes it to claim those objects and try to handle their hotplug, but that is not a good idea, because those objects have their own special hotplug handling anyway. For this reason, the hotplug_notify flag should not be set for ACPI device objects representing dock stations and the container scan handler should be made ignore those objects, so make that happen. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-16 01:51:01 +01:00
ACPI / scan: Add support for ACPI _CLS device matching Device drivers typically use ACPI _HIDs/_CIDs listed in struct device_driver acpi_match_table to match devices. However, for generic drivers, we do not want to list _HID for all supported devices. Also, certain classes of devices do not have _CID (e.g. SATA, USB). Instead, we can leverage ACPI _CLS, which specifies PCI-defined class code (i.e. base-class, subclass and programming interface). This patch adds support for matching ACPI devices using the _CLS method. To support loadable module, current design uses _HID or _CID to match device's modalias. With the new way of matching with _CLS this would requires modification to the current ACPI modalias key to include _CLS. This patch appends PCI-defined class-code to the existing ACPI modalias as following. acpi:<HID>:<CID1>:<CID2>:..:<CIDn>:<bbsspp>: E.g: # cat /sys/devices/platform/AMDI0600:00/modalias acpi:AMDI0600:010601: where bb is th base-class code, ss is te sub-class code, and pp is the programming interface code Since there would not be _HID/_CID in the ACPI matching table of the driver, this patch adds a field to acpi_device_id to specify the matching _CLS. static const struct acpi_device_id ahci_acpi_match[] = { { ACPI_DEVICE_CLASS(PCI_CLASS_STORAGE_SATA_AHCI, 0xffffff) }, {}, }; In this case, the corresponded entry in modules.alias file would be: alias acpi*:010601:* ahci_platform Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org> Signed-off-by: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-07-07 01:55:20 +02:00
ACPI / EC: Fix regression related to PM ops support in ECDT device commit a64a62ce9a380213dc9e192f762266d70c9b40ec upstream. On platforms (ASUS X550ZE and possibly all ASUS X series) with valid ECDT EC but invalid DSDT EC, EC PM ops won't be invoked as ECDT EC is not an ACPI device. Thus the following commit actually removed post-resume acpi_ec_enable_event() invocation for such platforms, and triggered a regression on them that after being resumed, EC (actually should be ECDT) driver stops handling EC events: Commit: c2b46d679b30c5c0d7eb47a21085943242bdd8dc Subject: ACPI / EC: Add PM operations to improve event handling for resume process Notice that the root cause actually is "ECDT is not an ACPI device" rather than "the timing of acpi_ec_enable_event() invocation", this patch fixes this issue by enumerating ECDT EC as an ACPI device. Due to the existence of the noirq stage, the ability of tuning the timing of acpi_ec_enable_event() invocation is still meaningful. This patch is a little bit different from the posted fix by moving acpi_config_boot_ec() from acpi_ec_ecdt_start() to acpi_ec_add() to make sure that EC event handling won't be stopped as long as the ACPI EC driver is bound. Thus the following sequence shouldn't disable EC event handling: unbind,suspend,resume,bind. Fixes: c2b46d679b30 (ACPI / EC: Add PM operations to improve event handling for resume process) Link: https://bugzilla.kernel.org/show_bug.cgi?id=196847 Reported-by: Luya Tshimbalanga <luya@fedoraproject.org> Tested-by: Luya Tshimbalanga <luya@fedoraproject.org> Signed-off-by: Lv Zheng <lv.zheng@intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-09-26 16:54:09 +08:00
ACPI: Implement acpi_dma_configure On DT based systems, the of_dma_configure() API implements DMA configuration for a given device. On ACPI systems an API equivalent to of_dma_configure() is missing which implies that it is currently not possible to set-up DMA operations for devices through the ACPI generic kernel layer. This patch fills the gap by introducing acpi_dma_configure/deconfigure() calls that for now are just wrappers around arch_setup_dma_ops() and arch_teardown_dma_ops() and also updates ACPI and PCI core code to use the newly introduced acpi_dma_configure/acpi_dma_deconfigure functions. Since acpi_dma_configure() is used to configure DMA operations, the function initializes the dma/coherent_dma masks to sane default values if the current masks are uninitialized (also to keep the default values consistent with DT systems) to make sure the device has a complete default DMA set-up. The DMA range size passed to arch_setup_dma_ops() is sized according to the device coherent_dma_mask (starting at address 0x0), mirroring the DT probing path behaviour when a dma-ranges property is not provided for the device being probed; this changes the current arch_setup_dma_ops() call parameters in the ACPI probing case, but since arch_setup_dma_ops() is a NOP on all architectures but ARM/ARM64 this patch does not change the current kernel behaviour on them. Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Acked-by: Bjorn Helgaas <bhelgaas@google.com> [pci] Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Tomasz Nowicki <tn@semihalf.com> Tested-by: Hanjun Guo <hanjun.guo@linaro.org> Tested-by: Tomasz Nowicki <tn@semihalf.com> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Robin Murphy <robin.murphy@arm.com> Cc: Tomasz Nowicki <tn@semihalf.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-11-21 10:01:39 +00:00
ACPI: Implement acpi_dma_configure On DT based systems, the of_dma_configure() API implements DMA configuration for a given device. On ACPI systems an API equivalent to of_dma_configure() is missing which implies that it is currently not possible to set-up DMA operations for devices through the ACPI generic kernel layer. This patch fills the gap by introducing acpi_dma_configure/deconfigure() calls that for now are just wrappers around arch_setup_dma_ops() and arch_teardown_dma_ops() and also updates ACPI and PCI core code to use the newly introduced acpi_dma_configure/acpi_dma_deconfigure functions. Since acpi_dma_configure() is used to configure DMA operations, the function initializes the dma/coherent_dma masks to sane default values if the current masks are uninitialized (also to keep the default values consistent with DT systems) to make sure the device has a complete default DMA set-up. The DMA range size passed to arch_setup_dma_ops() is sized according to the device coherent_dma_mask (starting at address 0x0), mirroring the DT probing path behaviour when a dma-ranges property is not provided for the device being probed; this changes the current arch_setup_dma_ops() call parameters in the ACPI probing case, but since arch_setup_dma_ops() is a NOP on all architectures but ARM/ARM64 this patch does not change the current kernel behaviour on them. Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Acked-by: Bjorn Helgaas <bhelgaas@google.com> [pci] Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Tomasz Nowicki <tn@semihalf.com> Tested-by: Hanjun Guo <hanjun.guo@linaro.org> Tested-by: Tomasz Nowicki <tn@semihalf.com> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Robin Murphy <robin.murphy@arm.com> Cc: Tomasz Nowicki <tn@semihalf.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-11-21 10:01:39 +00:00
ACPI: Implement acpi_dma_configure On DT based systems, the of_dma_configure() API implements DMA configuration for a given device. On ACPI systems an API equivalent to of_dma_configure() is missing which implies that it is currently not possible to set-up DMA operations for devices through the ACPI generic kernel layer. This patch fills the gap by introducing acpi_dma_configure/deconfigure() calls that for now are just wrappers around arch_setup_dma_ops() and arch_teardown_dma_ops() and also updates ACPI and PCI core code to use the newly introduced acpi_dma_configure/acpi_dma_deconfigure functions. Since acpi_dma_configure() is used to configure DMA operations, the function initializes the dma/coherent_dma masks to sane default values if the current masks are uninitialized (also to keep the default values consistent with DT systems) to make sure the device has a complete default DMA set-up. The DMA range size passed to arch_setup_dma_ops() is sized according to the device coherent_dma_mask (starting at address 0x0), mirroring the DT probing path behaviour when a dma-ranges property is not provided for the device being probed; this changes the current arch_setup_dma_ops() call parameters in the ACPI probing case, but since arch_setup_dma_ops() is a NOP on all architectures but ARM/ARM64 this patch does not change the current kernel behaviour on them. Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Acked-by: Bjorn Helgaas <bhelgaas@google.com> [pci] Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Tomasz Nowicki <tn@semihalf.com> Tested-by: Hanjun Guo <hanjun.guo@linaro.org> Tested-by: Tomasz Nowicki <tn@semihalf.com> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Robin Murphy <robin.murphy@arm.com> Cc: Tomasz Nowicki <tn@semihalf.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-11-21 10:01:39 +00:00
ACPI: Implement acpi_dma_configure On DT based systems, the of_dma_configure() API implements DMA configuration for a given device. On ACPI systems an API equivalent to of_dma_configure() is missing which implies that it is currently not possible to set-up DMA operations for devices through the ACPI generic kernel layer. This patch fills the gap by introducing acpi_dma_configure/deconfigure() calls that for now are just wrappers around arch_setup_dma_ops() and arch_teardown_dma_ops() and also updates ACPI and PCI core code to use the newly introduced acpi_dma_configure/acpi_dma_deconfigure functions. Since acpi_dma_configure() is used to configure DMA operations, the function initializes the dma/coherent_dma masks to sane default values if the current masks are uninitialized (also to keep the default values consistent with DT systems) to make sure the device has a complete default DMA set-up. The DMA range size passed to arch_setup_dma_ops() is sized according to the device coherent_dma_mask (starting at address 0x0), mirroring the DT probing path behaviour when a dma-ranges property is not provided for the device being probed; this changes the current arch_setup_dma_ops() call parameters in the ACPI probing case, but since arch_setup_dma_ops() is a NOP on all architectures but ARM/ARM64 this patch does not change the current kernel behaviour on them. Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Acked-by: Bjorn Helgaas <bhelgaas@google.com> [pci] Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Tomasz Nowicki <tn@semihalf.com> Tested-by: Hanjun Guo <hanjun.guo@linaro.org> Tested-by: Tomasz Nowicki <tn@semihalf.com> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Robin Murphy <robin.murphy@arm.com> Cc: Tomasz Nowicki <tn@semihalf.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-11-21 10:01:39 +00:00
ACPI: Add support for device specific properties Device Tree is used in many embedded systems to describe the system configuration to the OS. It supports attaching properties or name-value pairs to the devices it describe. With these properties one can pass additional information to the drivers that would not be available otherwise. ACPI is another configuration mechanism (among other things) typically seen, but not limited to, x86 machines. ACPI allows passing arbitrary data from methods but there has not been mechanism equivalent to Device Tree until the introduction of _DSD in the recent publication of the ACPI 5.1 specification. In order to facilitate ACPI usage in systems where Device Tree is typically used, it would be beneficial to standardize a way to retrieve Device Tree style properties from ACPI devices, which is what we do in this patch. If a given device described in ACPI namespace wants to export properties it must implement _DSD method (Device Specific Data, introduced with ACPI 5.1) that returns the properties in a package of packages. For example: Name (_DSD, Package () { ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"), Package () { Package () {"name1", <VALUE1>}, Package () {"name2", <VALUE2>}, ... } }) The UUID reserved for properties is daffd814-6eba-4d8c-8a91-bc9bbf4aa301 and is documented in the ACPI 5.1 companion document called "_DSD Implementation Guide" [1], [2]. We add several helper functions that can be used to extract these properties and convert them to different Linux data types. The ultimate goal is that we only have one device property API that retrieves the requested properties from Device Tree or from ACPI transparent to the caller. [1] http://www.uefi.org/sites/default/files/resources/_DSD-implementation-guide-toplevel.htm [2] http://www.uefi.org/sites/default/files/resources/_DSD-device-properties-UUID.pdf Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org> Reviewed-by: Josh Triplett <josh@joshtriplett.org> Reviewed-by: Grant Likely <grant.likely@linaro.org> Signed-off-by: Darren Hart <dvhart@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-10-21 13:33:55 +02:00
ACPI / scan: Add acpi_device objects for all device nodes in the namespace Modify the ACPI namespace scanning code to register a struct acpi_device object for every namespace node representing a device, processor and so on, even if the device represented by that namespace node is reported to be not present and not functional by _STA. There are multiple reasons to do that. First of all, it avoids quite a lot of overhead when struct acpi_device objects are deleted every time acpi_bus_trim() is run and then added again by a subsequent acpi_bus_scan() for the same scope, although the namespace objects they correspond to stay in memory all the time (which always is the case on a vast majority of systems). Second, it will allow user space to see that there are namespace nodes representing devices that are not present at the moment and may be added to the system. It will also allow user space to evaluate _SUN for those nodes to check what physical slots the "missing" devices may be put into and it will make sense to add a sysfs attribute for _STA evaluation after this change (that will be useful for thermal management on some systems). Next, it will help to consolidate the ACPI hotplug handling among subsystems by making it possible to store hotplug-related information in struct acpi_device objects in a standard common way. Finally, it will help to avoid a race condition related to the deletion of ACPI namespace nodes. Namely, namespace nodes may be deleted as a result of a table unload triggered by _EJ0 or _DCK. If a hotplug notification for one of those nodes is triggered right before the deletion and it executes a hotplug callback via acpi_hotplug_execute(), the ACPI handle passed to that callback may be stale when the callback actually runs. One way to work around that is to always pass struct acpi_device pointers to hotplug callbacks after doing a get_device() on the objects in question which eliminates the use-after-free possibility (the ACPI handles in those objects are invalidated by acpi_scan_drop_device(), so they will trigger ACPICA errors on attempts to use them). Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2013-11-22 21:54:37 +01:00
ACPI / scan: Add acpi_device objects for all device nodes in the namespace Modify the ACPI namespace scanning code to register a struct acpi_device object for every namespace node representing a device, processor and so on, even if the device represented by that namespace node is reported to be not present and not functional by _STA. There are multiple reasons to do that. First of all, it avoids quite a lot of overhead when struct acpi_device objects are deleted every time acpi_bus_trim() is run and then added again by a subsequent acpi_bus_scan() for the same scope, although the namespace objects they correspond to stay in memory all the time (which always is the case on a vast majority of systems). Second, it will allow user space to see that there are namespace nodes representing devices that are not present at the moment and may be added to the system. It will also allow user space to evaluate _SUN for those nodes to check what physical slots the "missing" devices may be put into and it will make sense to add a sysfs attribute for _STA evaluation after this change (that will be useful for thermal management on some systems). Next, it will help to consolidate the ACPI hotplug handling among subsystems by making it possible to store hotplug-related information in struct acpi_device objects in a standard common way. Finally, it will help to avoid a race condition related to the deletion of ACPI namespace nodes. Namely, namespace nodes may be deleted as a result of a table unload triggered by _EJ0 or _DCK. If a hotplug notification for one of those nodes is triggered right before the deletion and it executes a hotplug callback via acpi_hotplug_execute(), the ACPI handle passed to that callback may be stale when the callback actually runs. One way to work around that is to always pass struct acpi_device pointers to hotplug callbacks after doing a get_device() on the objects in question which eliminates the use-after-free possibility (the ACPI handles in those objects are invalidated by acpi_scan_drop_device(), so they will trigger ACPICA errors on attempts to use them). Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2013-11-22 21:54:37 +01:00
ACPI / scan: Add acpi_device objects for all device nodes in the namespace Modify the ACPI namespace scanning code to register a struct acpi_device object for every namespace node representing a device, processor and so on, even if the device represented by that namespace node is reported to be not present and not functional by _STA. There are multiple reasons to do that. First of all, it avoids quite a lot of overhead when struct acpi_device objects are deleted every time acpi_bus_trim() is run and then added again by a subsequent acpi_bus_scan() for the same scope, although the namespace objects they correspond to stay in memory all the time (which always is the case on a vast majority of systems). Second, it will allow user space to see that there are namespace nodes representing devices that are not present at the moment and may be added to the system. It will also allow user space to evaluate _SUN for those nodes to check what physical slots the "missing" devices may be put into and it will make sense to add a sysfs attribute for _STA evaluation after this change (that will be useful for thermal management on some systems). Next, it will help to consolidate the ACPI hotplug handling among subsystems by making it possible to store hotplug-related information in struct acpi_device objects in a standard common way. Finally, it will help to avoid a race condition related to the deletion of ACPI namespace nodes. Namely, namespace nodes may be deleted as a result of a table unload triggered by _EJ0 or _DCK. If a hotplug notification for one of those nodes is triggered right before the deletion and it executes a hotplug callback via acpi_hotplug_execute(), the ACPI handle passed to that callback may be stale when the callback actually runs. One way to work around that is to always pass struct acpi_device pointers to hotplug callbacks after doing a get_device() on the objects in question which eliminates the use-after-free possibility (the ACPI handles in those objects are invalidated by acpi_scan_drop_device(), so they will trigger ACPICA errors on attempts to use them). Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2013-11-22 21:54:37 +01:00
ACPI / hotplug / PCI: Consolidate ACPIPHP with ACPI core hotplug The ACPI-based PCI hotplug (ACPIPHP) code currently attaches its hotplug context objects directly to ACPI namespace nodes representing hotplug devices. However, after recent changes causing struct acpi_device to be created for every namespace node representing a device (regardless of its status), that is not necessary any more. Moreover, it's vulnerable to the theoretical issue that the ACPI handle passed in the context between handle_hotplug_event() and hotplug_event_work() may become invalid in the meantime (as a result of a concurrent table unload). In principle, this issue might be addressed by adding a non-empty release handler for ACPIPHP hotplug context objects analogous to acpi_scan_drop_device(), but that would duplicate the code in that function and in acpi_device_del_work_fn(). For this reason, it's better to modify ACPIPHP to attach its device hotplug contexts to struct device objects representing hotplug devices and make it use acpi_hotplug_notify_cb() as its notify handler. At the same time, acpi_device_hotplug() can be modified to dispatch the new .hp.event() callback pointing to acpiphp_hotplug_event() from ACPI device objects associated with PCI devices or use the generic ACPI device hotplug code for device objects with matching scan handlers. This allows the existing code duplication between ACPIPHP and the ACPI core to be reduced too and makes further ACPI-based device hotplug consolidation possible. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-06 17:31:37 +01:00
ACPI / dock: Dispatch dock notifications from the global notify handler The ACPI dock station code carries out an extra namespace scan before the main one in order to find and register all of the dock device objects. Then, it registers a notify handler for each of them for handling dock events. However, dock device objects need not be scanned for upfront. They very well can be enumerated and registered during the first phase of the main namespace scan, before attaching scan handlers and ACPI drivers to ACPI device objects. Then, the dependent devices can be added to the in the second phase. That makes it possible to drop the extra namespace scan, so do it. Moreover, it is not necessary to register notify handlers for all of the dock stations' namespace nodes, becuase notifications may be dispatched from the global notify handler for them. Do that and drop two functions used for dock notify handling, acpi_dock_deferred_cb() and dock_notify_handler(), that aren't necessary any more. Finally, some dock station objects have _HID objects matching the ACPI container scan handler which causes it to claim those objects and try to handle their hotplug, but that is not a good idea, because those objects have their own special hotplug handling anyway. For this reason, the hotplug_notify flag should not be set for ACPI device objects representing dock stations and the container scan handler should be made ignore those objects, so make that happen. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-16 01:51:01 +01:00
ACPI / hotplug / PCI: Consolidate ACPIPHP with ACPI core hotplug The ACPI-based PCI hotplug (ACPIPHP) code currently attaches its hotplug context objects directly to ACPI namespace nodes representing hotplug devices. However, after recent changes causing struct acpi_device to be created for every namespace node representing a device (regardless of its status), that is not necessary any more. Moreover, it's vulnerable to the theoretical issue that the ACPI handle passed in the context between handle_hotplug_event() and hotplug_event_work() may become invalid in the meantime (as a result of a concurrent table unload). In principle, this issue might be addressed by adding a non-empty release handler for ACPIPHP hotplug context objects analogous to acpi_scan_drop_device(), but that would duplicate the code in that function and in acpi_device_del_work_fn(). For this reason, it's better to modify ACPIPHP to attach its device hotplug contexts to struct device objects representing hotplug devices and make it use acpi_hotplug_notify_cb() as its notify handler. At the same time, acpi_device_hotplug() can be modified to dispatch the new .hp.event() callback pointing to acpiphp_hotplug_event() from ACPI device objects associated with PCI devices or use the generic ACPI device hotplug code for device objects with matching scan handlers. This allows the existing code duplication between ACPIPHP and the ACPI core to be reduced too and makes further ACPI-based device hotplug consolidation possible. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-06 17:31:37 +01:00
ACPI / hotplug / PCI: Consolidate ACPIPHP with ACPI core hotplug The ACPI-based PCI hotplug (ACPIPHP) code currently attaches its hotplug context objects directly to ACPI namespace nodes representing hotplug devices. However, after recent changes causing struct acpi_device to be created for every namespace node representing a device (regardless of its status), that is not necessary any more. Moreover, it's vulnerable to the theoretical issue that the ACPI handle passed in the context between handle_hotplug_event() and hotplug_event_work() may become invalid in the meantime (as a result of a concurrent table unload). In principle, this issue might be addressed by adding a non-empty release handler for ACPIPHP hotplug context objects analogous to acpi_scan_drop_device(), but that would duplicate the code in that function and in acpi_device_del_work_fn(). For this reason, it's better to modify ACPIPHP to attach its device hotplug contexts to struct device objects representing hotplug devices and make it use acpi_hotplug_notify_cb() as its notify handler. At the same time, acpi_device_hotplug() can be modified to dispatch the new .hp.event() callback pointing to acpiphp_hotplug_event() from ACPI device objects associated with PCI devices or use the generic ACPI device hotplug code for device objects with matching scan handlers. This allows the existing code duplication between ACPIPHP and the ACPI core to be reduced too and makes further ACPI-based device hotplug consolidation possible. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-06 17:31:37 +01:00
ACPI: Add _DEP support to fix battery issue on Asus T100TA ACPI 5.0 introduces _DEP (Operation Region Dependencies) to designate device objects that OSPM should assign a higher priority in start ordering due to future operation region accesses. On Asus T100TA, ACPI battery info are read from a I2C slave device via I2C operation region. Before I2C operation region handler is installed, battery _STA always returns 0. There is a _DEP method of designating start order under battery device node. This patch is to implement _DEP feature to fix battery issue on the Asus T100TA. Introducing acpi_dep_list and adding dep_unmet count in struct acpi_device. During ACPI namespace scan, create struct acpi_dep_data for a valid pair of master (device pointed to by _DEP)/ slave(device with _DEP), record master's and slave's ACPI handle in it and put it into acpi_dep_list. The dep_unmet count will increase by one if there is a device under its _DEP. Driver's probe() should return EPROBE_DEFER when find dep_unmet is larger than 0. When I2C operation region handler is installed, remove all struct acpi_dep_data on the acpi_dep_list whose master is pointed to I2C host controller and decrease slave's dep_unmet. When dep_unmet decreases to 0, all _DEP conditions are met and then do acpi_bus_attach() for the device in order to resolve battery _STA issue on the Asus T100TA. Link: https://bugzilla.kernel.org/show_bug.cgi?id=69011 Tested-by: Jan-Michael Brummer <jan.brummer@tabos.org> Tested-by: Adam Williamson <adamw@happyassassin.net> Tested-by: Michael Shigorin <shigorin@gmail.com> Acked-by: Wolfram Sang <wsa@the-dreams.de> Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Lan Tianyu <tianyu.lan@intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-11-23 21:22:54 +08:00
ACPI: Add _DEP support to fix battery issue on Asus T100TA ACPI 5.0 introduces _DEP (Operation Region Dependencies) to designate device objects that OSPM should assign a higher priority in start ordering due to future operation region accesses. On Asus T100TA, ACPI battery info are read from a I2C slave device via I2C operation region. Before I2C operation region handler is installed, battery _STA always returns 0. There is a _DEP method of designating start order under battery device node. This patch is to implement _DEP feature to fix battery issue on the Asus T100TA. Introducing acpi_dep_list and adding dep_unmet count in struct acpi_device. During ACPI namespace scan, create struct acpi_dep_data for a valid pair of master (device pointed to by _DEP)/ slave(device with _DEP), record master's and slave's ACPI handle in it and put it into acpi_dep_list. The dep_unmet count will increase by one if there is a device under its _DEP. Driver's probe() should return EPROBE_DEFER when find dep_unmet is larger than 0. When I2C operation region handler is installed, remove all struct acpi_dep_data on the acpi_dep_list whose master is pointed to I2C host controller and decrease slave's dep_unmet. When dep_unmet decreases to 0, all _DEP conditions are met and then do acpi_bus_attach() for the device in order to resolve battery _STA issue on the Asus T100TA. Link: https://bugzilla.kernel.org/show_bug.cgi?id=69011 Tested-by: Jan-Michael Brummer <jan.brummer@tabos.org> Tested-by: Adam Williamson <adamw@happyassassin.net> Tested-by: Michael Shigorin <shigorin@gmail.com> Acked-by: Wolfram Sang <wsa@the-dreams.de> Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Lan Tianyu <tianyu.lan@intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-11-23 21:22:54 +08:00
ACPI: Add _DEP support to fix battery issue on Asus T100TA ACPI 5.0 introduces _DEP (Operation Region Dependencies) to designate device objects that OSPM should assign a higher priority in start ordering due to future operation region accesses. On Asus T100TA, ACPI battery info are read from a I2C slave device via I2C operation region. Before I2C operation region handler is installed, battery _STA always returns 0. There is a _DEP method of designating start order under battery device node. This patch is to implement _DEP feature to fix battery issue on the Asus T100TA. Introducing acpi_dep_list and adding dep_unmet count in struct acpi_device. During ACPI namespace scan, create struct acpi_dep_data for a valid pair of master (device pointed to by _DEP)/ slave(device with _DEP), record master's and slave's ACPI handle in it and put it into acpi_dep_list. The dep_unmet count will increase by one if there is a device under its _DEP. Driver's probe() should return EPROBE_DEFER when find dep_unmet is larger than 0. When I2C operation region handler is installed, remove all struct acpi_dep_data on the acpi_dep_list whose master is pointed to I2C host controller and decrease slave's dep_unmet. When dep_unmet decreases to 0, all _DEP conditions are met and then do acpi_bus_attach() for the device in order to resolve battery _STA issue on the Asus T100TA. Link: https://bugzilla.kernel.org/show_bug.cgi?id=69011 Tested-by: Jan-Michael Brummer <jan.brummer@tabos.org> Tested-by: Adam Williamson <adamw@happyassassin.net> Tested-by: Michael Shigorin <shigorin@gmail.com> Acked-by: Wolfram Sang <wsa@the-dreams.de> Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Lan Tianyu <tianyu.lan@intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-11-23 21:22:54 +08:00
ACPI: Separate adding ACPI device objects from probing ACPI drivers Split the ACPI namespace scanning for devices into two passes, such that struct acpi_device objects are registerd in the first pass without probing ACPI drivers and the drivers are probed against them directly in the second pass. There are two main reasons for doing that. First, the ACPI PCI root bridge driver's .add() routine, acpi_pci_root_add(), causes struct pci_dev objects to be created for all PCI devices under the given root bridge. Usually, there are corresponding ACPI device nodes in the ACPI namespace for some of those devices and therefore there should be "companion" struct acpi_device objects to attach those struct pci_dev objects to. These struct acpi_device objects should exist when the corresponding struct pci_dev objects are created, but that is only guaranteed during boot and not during hotplug. This leads to a number of functional differences between the boot and the hotplug cases which are not strictly necessary and make the code more complicated. For example, this forces the ACPI PCI root bridge driver to defer the registration of the just created struct pci_dev objects and to use a special .start() callback routine, acpi_pci_root_start(), to make sure that all of the "companion" struct acpi_device objects will be present at PCI devices registration time during hotplug. If those differences can be eliminated, we will be able to consolidate the boot and hotplug code paths for the enumeration and registration of PCI devices and to reduce the complexity of that code quite a bit. The second reason is that, in general, it should be possible to resolve conflicts of resources assigned by the BIOS to different devices represented by ACPI namespace nodes before any drivers bind to them and before they are attached to "companion" objects representing physical devices (such as struct pci_dev). However, for this purpose we first need to enumerate all ACPI device nodes in the given namespace scope. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Yinghai Lu <yinghai@kernel.org> Acked-by: Toshi Kani <toshi.kani@hp.com>
2012-12-21 00:36:39 +01:00
ACPI / hotplug / PCI: Consolidate ACPIPHP with ACPI core hotplug The ACPI-based PCI hotplug (ACPIPHP) code currently attaches its hotplug context objects directly to ACPI namespace nodes representing hotplug devices. However, after recent changes causing struct acpi_device to be created for every namespace node representing a device (regardless of its status), that is not necessary any more. Moreover, it's vulnerable to the theoretical issue that the ACPI handle passed in the context between handle_hotplug_event() and hotplug_event_work() may become invalid in the meantime (as a result of a concurrent table unload). In principle, this issue might be addressed by adding a non-empty release handler for ACPIPHP hotplug context objects analogous to acpi_scan_drop_device(), but that would duplicate the code in that function and in acpi_device_del_work_fn(). For this reason, it's better to modify ACPIPHP to attach its device hotplug contexts to struct device objects representing hotplug devices and make it use acpi_hotplug_notify_cb() as its notify handler. At the same time, acpi_device_hotplug() can be modified to dispatch the new .hp.event() callback pointing to acpiphp_hotplug_event() from ACPI device objects associated with PCI devices or use the generic ACPI device hotplug code for device objects with matching scan handlers. This allows the existing code duplication between ACPIPHP and the ACPI core to be reduced too and makes further ACPI-based device hotplug consolidation possible. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-06 17:31:37 +01:00
ACPI: Add _DEP support to fix battery issue on Asus T100TA ACPI 5.0 introduces _DEP (Operation Region Dependencies) to designate device objects that OSPM should assign a higher priority in start ordering due to future operation region accesses. On Asus T100TA, ACPI battery info are read from a I2C slave device via I2C operation region. Before I2C operation region handler is installed, battery _STA always returns 0. There is a _DEP method of designating start order under battery device node. This patch is to implement _DEP feature to fix battery issue on the Asus T100TA. Introducing acpi_dep_list and adding dep_unmet count in struct acpi_device. During ACPI namespace scan, create struct acpi_dep_data for a valid pair of master (device pointed to by _DEP)/ slave(device with _DEP), record master's and slave's ACPI handle in it and put it into acpi_dep_list. The dep_unmet count will increase by one if there is a device under its _DEP. Driver's probe() should return EPROBE_DEFER when find dep_unmet is larger than 0. When I2C operation region handler is installed, remove all struct acpi_dep_data on the acpi_dep_list whose master is pointed to I2C host controller and decrease slave's dep_unmet. When dep_unmet decreases to 0, all _DEP conditions are met and then do acpi_bus_attach() for the device in order to resolve battery _STA issue on the Asus T100TA. Link: https://bugzilla.kernel.org/show_bug.cgi?id=69011 Tested-by: Jan-Michael Brummer <jan.brummer@tabos.org> Tested-by: Adam Williamson <adamw@happyassassin.net> Tested-by: Michael Shigorin <shigorin@gmail.com> Acked-by: Wolfram Sang <wsa@the-dreams.de> Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Lan Tianyu <tianyu.lan@intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-11-23 21:22:54 +08:00
ACPI / hotplug / PCI: Consolidate ACPIPHP with ACPI core hotplug The ACPI-based PCI hotplug (ACPIPHP) code currently attaches its hotplug context objects directly to ACPI namespace nodes representing hotplug devices. However, after recent changes causing struct acpi_device to be created for every namespace node representing a device (regardless of its status), that is not necessary any more. Moreover, it's vulnerable to the theoretical issue that the ACPI handle passed in the context between handle_hotplug_event() and hotplug_event_work() may become invalid in the meantime (as a result of a concurrent table unload). In principle, this issue might be addressed by adding a non-empty release handler for ACPIPHP hotplug context objects analogous to acpi_scan_drop_device(), but that would duplicate the code in that function and in acpi_device_del_work_fn(). For this reason, it's better to modify ACPIPHP to attach its device hotplug contexts to struct device objects representing hotplug devices and make it use acpi_hotplug_notify_cb() as its notify handler. At the same time, acpi_device_hotplug() can be modified to dispatch the new .hp.event() callback pointing to acpiphp_hotplug_event() from ACPI device objects associated with PCI devices or use the generic ACPI device hotplug code for device objects with matching scan handlers. This allows the existing code duplication between ACPIPHP and the ACPI core to be reduced too and makes further ACPI-based device hotplug consolidation possible. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-06 17:31:37 +01:00
ACPI: Separate adding ACPI device objects from probing ACPI drivers Split the ACPI namespace scanning for devices into two passes, such that struct acpi_device objects are registerd in the first pass without probing ACPI drivers and the drivers are probed against them directly in the second pass. There are two main reasons for doing that. First, the ACPI PCI root bridge driver's .add() routine, acpi_pci_root_add(), causes struct pci_dev objects to be created for all PCI devices under the given root bridge. Usually, there are corresponding ACPI device nodes in the ACPI namespace for some of those devices and therefore there should be "companion" struct acpi_device objects to attach those struct pci_dev objects to. These struct acpi_device objects should exist when the corresponding struct pci_dev objects are created, but that is only guaranteed during boot and not during hotplug. This leads to a number of functional differences between the boot and the hotplug cases which are not strictly necessary and make the code more complicated. For example, this forces the ACPI PCI root bridge driver to defer the registration of the just created struct pci_dev objects and to use a special .start() callback routine, acpi_pci_root_start(), to make sure that all of the "companion" struct acpi_device objects will be present at PCI devices registration time during hotplug. If those differences can be eliminated, we will be able to consolidate the boot and hotplug code paths for the enumeration and registration of PCI devices and to reduce the complexity of that code quite a bit. The second reason is that, in general, it should be possible to resolve conflicts of resources assigned by the BIOS to different devices represented by ACPI namespace nodes before any drivers bind to them and before they are attached to "companion" objects representing physical devices (such as struct pci_dev). However, for this purpose we first need to enumerate all ACPI device nodes in the given namespace scope. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Yinghai Lu <yinghai@kernel.org> Acked-by: Toshi Kani <toshi.kani@hp.com>
2012-12-21 00:36:39 +01:00
ACPI / dock: Dispatch dock notifications from the global notify handler The ACPI dock station code carries out an extra namespace scan before the main one in order to find and register all of the dock device objects. Then, it registers a notify handler for each of them for handling dock events. However, dock device objects need not be scanned for upfront. They very well can be enumerated and registered during the first phase of the main namespace scan, before attaching scan handlers and ACPI drivers to ACPI device objects. Then, the dependent devices can be added to the in the second phase. That makes it possible to drop the extra namespace scan, so do it. Moreover, it is not necessary to register notify handlers for all of the dock stations' namespace nodes, becuase notifications may be dispatched from the global notify handler for them. Do that and drop two functions used for dock notify handling, acpi_dock_deferred_cb() and dock_notify_handler(), that aren't necessary any more. Finally, some dock station objects have _HID objects matching the ACPI container scan handler which causes it to claim those objects and try to handle their hotplug, but that is not a good idea, because those objects have their own special hotplug handling anyway. For this reason, the hotplug_notify flag should not be set for ACPI device objects representing dock stations and the container scan handler should be made ignore those objects, so make that happen. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-16 01:51:01 +01:00
ACPI / dock: Dispatch dock notifications from the global notify handler The ACPI dock station code carries out an extra namespace scan before the main one in order to find and register all of the dock device objects. Then, it registers a notify handler for each of them for handling dock events. However, dock device objects need not be scanned for upfront. They very well can be enumerated and registered during the first phase of the main namespace scan, before attaching scan handlers and ACPI drivers to ACPI device objects. Then, the dependent devices can be added to the in the second phase. That makes it possible to drop the extra namespace scan, so do it. Moreover, it is not necessary to register notify handlers for all of the dock stations' namespace nodes, becuase notifications may be dispatched from the global notify handler for them. Do that and drop two functions used for dock notify handling, acpi_dock_deferred_cb() and dock_notify_handler(), that aren't necessary any more. Finally, some dock station objects have _HID objects matching the ACPI container scan handler which causes it to claim those objects and try to handle their hotplug, but that is not a good idea, because those objects have their own special hotplug handling anyway. For this reason, the hotplug_notify flag should not be set for ACPI device objects representing dock stations and the container scan handler should be made ignore those objects, so make that happen. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-02-16 01:51:01 +01:00
ACPI / scan: Add acpi_device objects for all device nodes in the namespace Modify the ACPI namespace scanning code to register a struct acpi_device object for every namespace node representing a device, processor and so on, even if the device represented by that namespace node is reported to be not present and not functional by _STA. There are multiple reasons to do that. First of all, it avoids quite a lot of overhead when struct acpi_device objects are deleted every time acpi_bus_trim() is run and then added again by a subsequent acpi_bus_scan() for the same scope, although the namespace objects they correspond to stay in memory all the time (which always is the case on a vast majority of systems). Second, it will allow user space to see that there are namespace nodes representing devices that are not present at the moment and may be added to the system. It will also allow user space to evaluate _SUN for those nodes to check what physical slots the "missing" devices may be put into and it will make sense to add a sysfs attribute for _STA evaluation after this change (that will be useful for thermal management on some systems). Next, it will help to consolidate the ACPI hotplug handling among subsystems by making it possible to store hotplug-related information in struct acpi_device objects in a standard common way. Finally, it will help to avoid a race condition related to the deletion of ACPI namespace nodes. Namely, namespace nodes may be deleted as a result of a table unload triggered by _EJ0 or _DCK. If a hotplug notification for one of those nodes is triggered right before the deletion and it executes a hotplug callback via acpi_hotplug_execute(), the ACPI handle passed to that callback may be stale when the callback actually runs. One way to work around that is to always pass struct acpi_device pointers to hotplug callbacks after doing a get_device() on the objects in question which eliminates the use-after-free possibility (the ACPI handles in those objects are invalidated by acpi_scan_drop_device(), so they will trigger ACPICA errors on attempts to use them). Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2013-11-22 21:54:37 +01:00
ACPI / PM: Fix PM initialization for devices that are not present If an ACPI device object whose _STA returns 0 (not present and not functional) has _PR0 or _PS0, its power_manageable flag will be set and acpi_bus_init_power() will return 0 for it. Consequently, if such a device object is passed to the ACPI device PM functions, they will attempt to carry out the requested operation on the device, although they should not do that for devices that are not present. To fix that problem make acpi_bus_init_power() return an error code for devices that are not present which will cause power_manageable to be cleared for them as appropriate in acpi_bus_get_power_flags(). However, the lists of power resources should not be freed for the device in that case, so modify acpi_bus_get_power_flags() to keep those lists even if acpi_bus_init_power() returns an error. Accordingly, when deciding whether or not the lists of power resources need to be freed, acpi_free_power_resources_lists() should check the power.flags.power_resources flag instead of flags.power_manageable, so make that change too. Furthermore, if acpi_bus_attach() sees that flags.initialized is unset for the given device, it should reset the power management settings of the device and re-initialize them from scratch instead of relying on the previous settings (the device may have appeared after being not present previously, for example), so make it use the 'valid' flag of the D0 power state as the initial value of flags.power_manageable for it and call acpi_bus_init_power() to discover its current power state. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Cc: 3.10+ <stable@vger.kernel.org> # 3.10+
2015-01-01 23:38:28 +01:00
ACPI / scan: Add acpi_device objects for all device nodes in the namespace Modify the ACPI namespace scanning code to register a struct acpi_device object for every namespace node representing a device, processor and so on, even if the device represented by that namespace node is reported to be not present and not functional by _STA. There are multiple reasons to do that. First of all, it avoids quite a lot of overhead when struct acpi_device objects are deleted every time acpi_bus_trim() is run and then added again by a subsequent acpi_bus_scan() for the same scope, although the namespace objects they correspond to stay in memory all the time (which always is the case on a vast majority of systems). Second, it will allow user space to see that there are namespace nodes representing devices that are not present at the moment and may be added to the system. It will also allow user space to evaluate _SUN for those nodes to check what physical slots the "missing" devices may be put into and it will make sense to add a sysfs attribute for _STA evaluation after this change (that will be useful for thermal management on some systems). Next, it will help to consolidate the ACPI hotplug handling among subsystems by making it possible to store hotplug-related information in struct acpi_device objects in a standard common way. Finally, it will help to avoid a race condition related to the deletion of ACPI namespace nodes. Namely, namespace nodes may be deleted as a result of a table unload triggered by _EJ0 or _DCK. If a hotplug notification for one of those nodes is triggered right before the deletion and it executes a hotplug callback via acpi_hotplug_execute(), the ACPI handle passed to that callback may be stale when the callback actually runs. One way to work around that is to always pass struct acpi_device pointers to hotplug callbacks after doing a get_device() on the objects in question which eliminates the use-after-free possibility (the ACPI handles in those objects are invalidated by acpi_scan_drop_device(), so they will trigger ACPICA errors on attempts to use them). Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2013-11-22 21:54:37 +01:00
ACPI / PM: Fix PM initialization for devices that are not present If an ACPI device object whose _STA returns 0 (not present and not functional) has _PR0 or _PS0, its power_manageable flag will be set and acpi_bus_init_power() will return 0 for it. Consequently, if such a device object is passed to the ACPI device PM functions, they will attempt to carry out the requested operation on the device, although they should not do that for devices that are not present. To fix that problem make acpi_bus_init_power() return an error code for devices that are not present which will cause power_manageable to be cleared for them as appropriate in acpi_bus_get_power_flags(). However, the lists of power resources should not be freed for the device in that case, so modify acpi_bus_get_power_flags() to keep those lists even if acpi_bus_init_power() returns an error. Accordingly, when deciding whether or not the lists of power resources need to be freed, acpi_free_power_resources_lists() should check the power.flags.power_resources flag instead of flags.power_manageable, so make that change too. Furthermore, if acpi_bus_attach() sees that flags.initialized is unset for the given device, it should reset the power management settings of the device and re-initialize them from scratch instead of relying on the previous settings (the device may have appeared after being not present previously, for example), so make it use the 'valid' flag of the D0 power state as the initial value of flags.power_manageable for it and call acpi_bus_init_power() to discover its current power state. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Cc: 3.10+ <stable@vger.kernel.org> # 3.10+
2015-01-01 23:38:28 +01:00
ACPI / scan: Add acpi_device objects for all device nodes in the namespace Modify the ACPI namespace scanning code to register a struct acpi_device object for every namespace node representing a device, processor and so on, even if the device represented by that namespace node is reported to be not present and not functional by _STA. There are multiple reasons to do that. First of all, it avoids quite a lot of overhead when struct acpi_device objects are deleted every time acpi_bus_trim() is run and then added again by a subsequent acpi_bus_scan() for the same scope, although the namespace objects they correspond to stay in memory all the time (which always is the case on a vast majority of systems). Second, it will allow user space to see that there are namespace nodes representing devices that are not present at the moment and may be added to the system. It will also allow user space to evaluate _SUN for those nodes to check what physical slots the "missing" devices may be put into and it will make sense to add a sysfs attribute for _STA evaluation after this change (that will be useful for thermal management on some systems). Next, it will help to consolidate the ACPI hotplug handling among subsystems by making it possible to store hotplug-related information in struct acpi_device objects in a standard common way. Finally, it will help to avoid a race condition related to the deletion of ACPI namespace nodes. Namely, namespace nodes may be deleted as a result of a table unload triggered by _EJ0 or _DCK. If a hotplug notification for one of those nodes is triggered right before the deletion and it executes a hotplug callback via acpi_hotplug_execute(), the ACPI handle passed to that callback may be stale when the callback actually runs. One way to work around that is to always pass struct acpi_device pointers to hotplug callbacks after doing a get_device() on the objects in question which eliminates the use-after-free possibility (the ACPI handles in those objects are invalidated by acpi_scan_drop_device(), so they will trigger ACPICA errors on attempts to use them). Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2013-11-22 21:54:37 +01:00
ACPI / scan: Add acpi_device objects for all device nodes in the namespace Modify the ACPI namespace scanning code to register a struct acpi_device object for every namespace node representing a device, processor and so on, even if the device represented by that namespace node is reported to be not present and not functional by _STA. There are multiple reasons to do that. First of all, it avoids quite a lot of overhead when struct acpi_device objects are deleted every time acpi_bus_trim() is run and then added again by a subsequent acpi_bus_scan() for the same scope, although the namespace objects they correspond to stay in memory all the time (which always is the case on a vast majority of systems). Second, it will allow user space to see that there are namespace nodes representing devices that are not present at the moment and may be added to the system. It will also allow user space to evaluate _SUN for those nodes to check what physical slots the "missing" devices may be put into and it will make sense to add a sysfs attribute for _STA evaluation after this change (that will be useful for thermal management on some systems). Next, it will help to consolidate the ACPI hotplug handling among subsystems by making it possible to store hotplug-related information in struct acpi_device objects in a standard common way. Finally, it will help to avoid a race condition related to the deletion of ACPI namespace nodes. Namely, namespace nodes may be deleted as a result of a table unload triggered by _EJ0 or _DCK. If a hotplug notification for one of those nodes is triggered right before the deletion and it executes a hotplug callback via acpi_hotplug_execute(), the ACPI handle passed to that callback may be stale when the callback actually runs. One way to work around that is to always pass struct acpi_device pointers to hotplug callbacks after doing a get_device() on the objects in question which eliminates the use-after-free possibility (the ACPI handles in those objects are invalidated by acpi_scan_drop_device(), so they will trigger ACPICA errors on attempts to use them). Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2013-11-22 21:54:37 +01:00
ACPI / scan: Add acpi_device objects for all device nodes in the namespace Modify the ACPI namespace scanning code to register a struct acpi_device object for every namespace node representing a device, processor and so on, even if the device represented by that namespace node is reported to be not present and not functional by _STA. There are multiple reasons to do that. First of all, it avoids quite a lot of overhead when struct acpi_device objects are deleted every time acpi_bus_trim() is run and then added again by a subsequent acpi_bus_scan() for the same scope, although the namespace objects they correspond to stay in memory all the time (which always is the case on a vast majority of systems). Second, it will allow user space to see that there are namespace nodes representing devices that are not present at the moment and may be added to the system. It will also allow user space to evaluate _SUN for those nodes to check what physical slots the "missing" devices may be put into and it will make sense to add a sysfs attribute for _STA evaluation after this change (that will be useful for thermal management on some systems). Next, it will help to consolidate the ACPI hotplug handling among subsystems by making it possible to store hotplug-related information in struct acpi_device objects in a standard common way. Finally, it will help to avoid a race condition related to the deletion of ACPI namespace nodes. Namely, namespace nodes may be deleted as a result of a table unload triggered by _EJ0 or _DCK. If a hotplug notification for one of those nodes is triggered right before the deletion and it executes a hotplug callback via acpi_hotplug_execute(), the ACPI handle passed to that callback may be stale when the callback actually runs. One way to work around that is to always pass struct acpi_device pointers to hotplug callbacks after doing a get_device() on the objects in question which eliminates the use-after-free possibility (the ACPI handles in those objects are invalidated by acpi_scan_drop_device(), so they will trigger ACPICA errors on attempts to use them). Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2013-11-22 21:54:37 +01:00
ACPI / scan: Add acpi_device objects for all device nodes in the namespace Modify the ACPI namespace scanning code to register a struct acpi_device object for every namespace node representing a device, processor and so on, even if the device represented by that namespace node is reported to be not present and not functional by _STA. There are multiple reasons to do that. First of all, it avoids quite a lot of overhead when struct acpi_device objects are deleted every time acpi_bus_trim() is run and then added again by a subsequent acpi_bus_scan() for the same scope, although the namespace objects they correspond to stay in memory all the time (which always is the case on a vast majority of systems). Second, it will allow user space to see that there are namespace nodes representing devices that are not present at the moment and may be added to the system. It will also allow user space to evaluate _SUN for those nodes to check what physical slots the "missing" devices may be put into and it will make sense to add a sysfs attribute for _STA evaluation after this change (that will be useful for thermal management on some systems). Next, it will help to consolidate the ACPI hotplug handling among subsystems by making it possible to store hotplug-related information in struct acpi_device objects in a standard common way. Finally, it will help to avoid a race condition related to the deletion of ACPI namespace nodes. Namely, namespace nodes may be deleted as a result of a table unload triggered by _EJ0 or _DCK. If a hotplug notification for one of those nodes is triggered right before the deletion and it executes a hotplug callback via acpi_hotplug_execute(), the ACPI handle passed to that callback may be stale when the callback actually runs. One way to work around that is to always pass struct acpi_device pointers to hotplug callbacks after doing a get_device() on the objects in question which eliminates the use-after-free possibility (the ACPI handles in those objects are invalidated by acpi_scan_drop_device(), so they will trigger ACPICA errors on attempts to use them). Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2013-11-22 21:54:37 +01:00
ACPI: Add _DEP support to fix battery issue on Asus T100TA ACPI 5.0 introduces _DEP (Operation Region Dependencies) to designate device objects that OSPM should assign a higher priority in start ordering due to future operation region accesses. On Asus T100TA, ACPI battery info are read from a I2C slave device via I2C operation region. Before I2C operation region handler is installed, battery _STA always returns 0. There is a _DEP method of designating start order under battery device node. This patch is to implement _DEP feature to fix battery issue on the Asus T100TA. Introducing acpi_dep_list and adding dep_unmet count in struct acpi_device. During ACPI namespace scan, create struct acpi_dep_data for a valid pair of master (device pointed to by _DEP)/ slave(device with _DEP), record master's and slave's ACPI handle in it and put it into acpi_dep_list. The dep_unmet count will increase by one if there is a device under its _DEP. Driver's probe() should return EPROBE_DEFER when find dep_unmet is larger than 0. When I2C operation region handler is installed, remove all struct acpi_dep_data on the acpi_dep_list whose master is pointed to I2C host controller and decrease slave's dep_unmet. When dep_unmet decreases to 0, all _DEP conditions are met and then do acpi_bus_attach() for the device in order to resolve battery _STA issue on the Asus T100TA. Link: https://bugzilla.kernel.org/show_bug.cgi?id=69011 Tested-by: Jan-Michael Brummer <jan.brummer@tabos.org> Tested-by: Adam Williamson <adamw@happyassassin.net> Tested-by: Michael Shigorin <shigorin@gmail.com> Acked-by: Wolfram Sang <wsa@the-dreams.de> Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Lan Tianyu <tianyu.lan@intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-11-23 21:22:54 +08:00
ACPI / hotplug: Fix concurrency issues and memory leaks This changeset is aimed at fixing a few different but related problems in the ACPI hotplug infrastructure. First of all, since notify handlers may be run in parallel with acpi_bus_scan(), acpi_bus_trim() and acpi_bus_hot_remove_device() and some of them are installed for ACPI handles that have no struct acpi_device objects attached (i.e. before those objects are created), those notify handlers have to take acpi_scan_lock to prevent races from taking place (e.g. a struct acpi_device is found to be present for the given ACPI handle, but right after that it is removed by acpi_bus_trim() running in parallel to the given notify handler). Moreover, since some of them call acpi_bus_scan() and acpi_bus_trim(), this leads to the conclusion that acpi_scan_lock should be acquired by the callers of these two funtions rather by these functions themselves. For these reasons, make all notify handlers that can handle device addition and eject events take acpi_scan_lock and remove the acpi_scan_lock locking from acpi_bus_scan() and acpi_bus_trim(). Accordingly, update all of their users to make sure that they are always called under acpi_scan_lock. Furthermore, since eject operations are carried out asynchronously with respect to the notify events that trigger them, with the help of acpi_bus_hot_remove_device(), even if notify handlers take the ACPI scan lock, it still is possible that, for example, acpi_bus_trim() will run between acpi_bus_hot_remove_device() and the notify handler that scheduled its execution and that acpi_bus_trim() will remove the device node passed to acpi_bus_hot_remove_device() for ejection. In that case, the struct acpi_device object obtained by acpi_bus_hot_remove_device() will be invalid and not-so-funny things will ensue. To protect agaist that, make the users of acpi_bus_hot_remove_device() run get_device() on ACPI device node objects that are about to be passed to it and make acpi_bus_hot_remove_device() run put_device() on them and check if their ACPI handles are not NULL (make acpi_device_unregister() clear the device nodes' ACPI handles for that check to work). Finally, observe that acpi_os_hotplug_execute() actually can fail, in which case its caller ought to free memory allocated for the context object to prevent leaks from happening. It also needs to run put_device() on the device node that it ran get_device() on previously in that case. Modify the code accordingly. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Yinghai Lu <yinghai@kernel.org>
2013-02-13 14:36:47 +01:00
ACPI / hotplug: Fix concurrency issues and memory leaks This changeset is aimed at fixing a few different but related problems in the ACPI hotplug infrastructure. First of all, since notify handlers may be run in parallel with acpi_bus_scan(), acpi_bus_trim() and acpi_bus_hot_remove_device() and some of them are installed for ACPI handles that have no struct acpi_device objects attached (i.e. before those objects are created), those notify handlers have to take acpi_scan_lock to prevent races from taking place (e.g. a struct acpi_device is found to be present for the given ACPI handle, but right after that it is removed by acpi_bus_trim() running in parallel to the given notify handler). Moreover, since some of them call acpi_bus_scan() and acpi_bus_trim(), this leads to the conclusion that acpi_scan_lock should be acquired by the callers of these two funtions rather by these functions themselves. For these reasons, make all notify handlers that can handle device addition and eject events take acpi_scan_lock and remove the acpi_scan_lock locking from acpi_bus_scan() and acpi_bus_trim(). Accordingly, update all of their users to make sure that they are always called under acpi_scan_lock. Furthermore, since eject operations are carried out asynchronously with respect to the notify events that trigger them, with the help of acpi_bus_hot_remove_device(), even if notify handlers take the ACPI scan lock, it still is possible that, for example, acpi_bus_trim() will run between acpi_bus_hot_remove_device() and the notify handler that scheduled its execution and that acpi_bus_trim() will remove the device node passed to acpi_bus_hot_remove_device() for ejection. In that case, the struct acpi_device object obtained by acpi_bus_hot_remove_device() will be invalid and not-so-funny things will ensue. To protect agaist that, make the users of acpi_bus_hot_remove_device() run get_device() on ACPI device node objects that are about to be passed to it and make acpi_bus_hot_remove_device() run put_device() on them and check if their ACPI handles are not NULL (make acpi_device_unregister() clear the device nodes' ACPI handles for that check to work). Finally, observe that acpi_os_hotplug_execute() actually can fail, in which case its caller ought to free memory allocated for the context object to prevent leaks from happening. It also needs to run put_device() on the device node that it ran get_device() on previously in that case. Modify the code accordingly. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Yinghai Lu <yinghai@kernel.org>
2013-02-13 14:36:47 +01:00
ACPI / hotplug: Fix concurrency issues and memory leaks This changeset is aimed at fixing a few different but related problems in the ACPI hotplug infrastructure. First of all, since notify handlers may be run in parallel with acpi_bus_scan(), acpi_bus_trim() and acpi_bus_hot_remove_device() and some of them are installed for ACPI handles that have no struct acpi_device objects attached (i.e. before those objects are created), those notify handlers have to take acpi_scan_lock to prevent races from taking place (e.g. a struct acpi_device is found to be present for the given ACPI handle, but right after that it is removed by acpi_bus_trim() running in parallel to the given notify handler). Moreover, since some of them call acpi_bus_scan() and acpi_bus_trim(), this leads to the conclusion that acpi_scan_lock should be acquired by the callers of these two funtions rather by these functions themselves. For these reasons, make all notify handlers that can handle device addition and eject events take acpi_scan_lock and remove the acpi_scan_lock locking from acpi_bus_scan() and acpi_bus_trim(). Accordingly, update all of their users to make sure that they are always called under acpi_scan_lock. Furthermore, since eject operations are carried out asynchronously with respect to the notify events that trigger them, with the help of acpi_bus_hot_remove_device(), even if notify handlers take the ACPI scan lock, it still is possible that, for example, acpi_bus_trim() will run between acpi_bus_hot_remove_device() and the notify handler that scheduled its execution and that acpi_bus_trim() will remove the device node passed to acpi_bus_hot_remove_device() for ejection. In that case, the struct acpi_device object obtained by acpi_bus_hot_remove_device() will be invalid and not-so-funny things will ensue. To protect agaist that, make the users of acpi_bus_hot_remove_device() run get_device() on ACPI device node objects that are about to be passed to it and make acpi_bus_hot_remove_device() run put_device() on them and check if their ACPI handles are not NULL (make acpi_device_unregister() clear the device nodes' ACPI handles for that check to work). Finally, observe that acpi_os_hotplug_execute() actually can fail, in which case its caller ought to free memory allocated for the context object to prevent leaks from happening. It also needs to run put_device() on the device node that it ran get_device() on previously in that case. Modify the code accordingly. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Yinghai Lu <yinghai@kernel.org>
2013-02-13 14:36:47 +01:00
ACPI / EC: Fix regression related to PM ops support in ECDT device commit a64a62ce9a380213dc9e192f762266d70c9b40ec upstream. On platforms (ASUS X550ZE and possibly all ASUS X series) with valid ECDT EC but invalid DSDT EC, EC PM ops won't be invoked as ECDT EC is not an ACPI device. Thus the following commit actually removed post-resume acpi_ec_enable_event() invocation for such platforms, and triggered a regression on them that after being resumed, EC (actually should be ECDT) driver stops handling EC events: Commit: c2b46d679b30c5c0d7eb47a21085943242bdd8dc Subject: ACPI / EC: Add PM operations to improve event handling for resume process Notice that the root cause actually is "ECDT is not an ACPI device" rather than "the timing of acpi_ec_enable_event() invocation", this patch fixes this issue by enumerating ECDT EC as an ACPI device. Due to the existence of the noirq stage, the ability of tuning the timing of acpi_ec_enable_event() invocation is still meaningful. This patch is a little bit different from the posted fix by moving acpi_config_boot_ec() from acpi_ec_ecdt_start() to acpi_ec_add() to make sure that EC event handling won't be stopped as long as the ACPI EC driver is bound. Thus the following sequence shouldn't disable EC event handling: unbind,suspend,resume,bind. Fixes: c2b46d679b30 (ACPI / EC: Add PM operations to improve event handling for resume process) Link: https://bugzilla.kernel.org/show_bug.cgi?id=196847 Reported-by: Luya Tshimbalanga <luya@fedoraproject.org> Tested-by: Luya Tshimbalanga <luya@fedoraproject.org> Signed-off-by: Lv Zheng <lv.zheng@intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-09-26 16:54:09 +08:00
ACPI / processor: Use common hotplug infrastructure Split the ACPI processor driver into two parts, one that is non-modular, resides in the ACPI core and handles the enumeration and hotplug of processors and one that implements the rest of the existing processor driver functionality. The non-modular part uses an ACPI scan handler object to enumerate processors on the basis of information provided by the ACPI namespace and to hook up with the common ACPI hotplug infrastructure. It also populates the ACPI handle of each processor device having a corresponding object in the ACPI namespace, which allows the driver proper to bind to those devices, and makes the driver bind to them if it is readily available (i.e. loaded) when the scan handler's .attach() routine is running. There are a few reasons to make this change. First, switching the ACPI processor driver to using the common ACPI hotplug infrastructure reduces code duplication and size considerably, even though a new file is created along with a header comment etc. Second, since the common hotplug code attempts to offline devices before starting the (non-reversible) removal procedure, it will abort (and possibly roll back) hot-remove operations involving processors if cpu_down() returns an error code for one of them instead of continuing them blindly (if /sys/firmware/acpi/hotplug/force_remove is unset). That is a more desirable behavior than what the current code does. Finally, the separation of the scan/hotplug part from the driver proper makes it possible to simplify the driver's .remove() routine, because it doesn't need to worry about the possible cleanup related to processor removal any more (the scan/hotplug part is responsible for that now) and can handle device removal and driver removal symmetricaly (i.e. as appropriate). Some user-visible changes in sysfs are made (for example, the 'sysdev' link from the ACPI device node to the processor device's directory is gone and a 'physical_node' link is present instead and a corresponding 'firmware_node' is present in the processor device's directory, the processor driver is now visible under /sys/bus/cpu/drivers/ and bound to the processor device), but that shouldn't affect the functionality that users care about (frequency scaling, C-states and thermal management). Tested on my venerable Toshiba Portege R500. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Toshi Kani <toshi.kani@hp.com>
2013-05-03 00:26:22 +02:00
ACPI / scan: Add special handler for Intel Lynxpoint LPSS devices Devices on the Intel Lynxpoint Low Power Subsystem (LPSS) have some common features that aren't shared with any other platform devices, including the clock and LTR (Latency Tolerance Reporting) registers. It is better to handle those features in common code than to bother device drivers with doing that (I/O functionality-wise the LPSS devices are generally compatible with other devices that don't have those special registers and may be handled by the same drivers). The clock registers of the LPSS devices are now taken care of by the special clk-x86-lpss driver, but the MMIO mappings used for accessing those registers can also be used for accessing the LTR registers on those devices (LTR support for the Lynxpoint LPSS is going to be added by a subsequent patch). Thus it is convenient to add a special ACPI scan handler for the Lynxpoint LPSS devices that will create the MMIO mappings for accessing the clock (and LTR in the future) registers and will register the LPSS devices' clocks, so the clk-x86-lpss driver will only need to take care of the main Lynxpoint LPSS clock. Introduce a special ACPI scan handler for Intel Lynxpoint LPSS devices as described above. This also reduces overhead related to browsing the ACPI namespace in search of the LPSS devices before the registration of their clocks, removes some LPSS-specific (and somewhat ugly) code from acpi_platform.c and shrinks the overall code size slightly. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Mike Turquette <mturquette@linaro.org>
2013-03-06 23:46:20 +01:00
ACPI / PNP: use device ID list for PNPACPI device enumeration ACPI can be used to enumerate PNP devices, but the code does not handle this in the right way currently. Namely, if an ACPI device object 1. Has a _CRS method, 2. Has an identification of "three capital characters followed by four hex digits", 3. Is not in the excluded IDs list, it will be enumerated to PNP bus (that is, a PNP device object will be create for it). This means that, actually, the PNP bus type is used as the default bus type for enumerating _HID devices in ACPI. However, more and more _HID devices need to be enumerated to the platform bus instead (that is, platform device objects need to be created for them). As a result, the device ID list in acpi_platform.c is used to enforce creating platform device objects rather than PNP device objects for matching devices. That list has been continuously growing recently, unfortunately, and it is pretty much guaranteed to grow even more in the future. To address that problem it is better to enumerate _HID devices as platform devices by default. To this end, change the way of enumerating PNP devices by adding a PNP ACPI scan handler that will use a device ID list to create PNP devices for the ACPI device objects whose device IDs are present in that list. The initial device ID list in the PNP ACPI scan handler contains all of the pnp_device_id strings from all the existing PNP drivers, so this change should be transparent to the PNP core and all of the PNP drivers. Still, in the future it should be possible to reduce its size by converting PNP drivers that need not be PNP for any technical reasons into platform drivers. Signed-off-by: Zhang Rui <rui.zhang@intel.com> [rjw: Rewrote the changelog, modified the PNP ACPI scan handler code] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2014-05-30 04:23:01 +02:00
ACPI / hotplug: Fix concurrency issues and memory leaks This changeset is aimed at fixing a few different but related problems in the ACPI hotplug infrastructure. First of all, since notify handlers may be run in parallel with acpi_bus_scan(), acpi_bus_trim() and acpi_bus_hot_remove_device() and some of them are installed for ACPI handles that have no struct acpi_device objects attached (i.e. before those objects are created), those notify handlers have to take acpi_scan_lock to prevent races from taking place (e.g. a struct acpi_device is found to be present for the given ACPI handle, but right after that it is removed by acpi_bus_trim() running in parallel to the given notify handler). Moreover, since some of them call acpi_bus_scan() and acpi_bus_trim(), this leads to the conclusion that acpi_scan_lock should be acquired by the callers of these two funtions rather by these functions themselves. For these reasons, make all notify handlers that can handle device addition and eject events take acpi_scan_lock and remove the acpi_scan_lock locking from acpi_bus_scan() and acpi_bus_trim(). Accordingly, update all of their users to make sure that they are always called under acpi_scan_lock. Furthermore, since eject operations are carried out asynchronously with respect to the notify events that trigger them, with the help of acpi_bus_hot_remove_device(), even if notify handlers take the ACPI scan lock, it still is possible that, for example, acpi_bus_trim() will run between acpi_bus_hot_remove_device() and the notify handler that scheduled its execution and that acpi_bus_trim() will remove the device node passed to acpi_bus_hot_remove_device() for ejection. In that case, the struct acpi_device object obtained by acpi_bus_hot_remove_device() will be invalid and not-so-funny things will ensue. To protect agaist that, make the users of acpi_bus_hot_remove_device() run get_device() on ACPI device node objects that are about to be passed to it and make acpi_bus_hot_remove_device() run put_device() on them and check if their ACPI handles are not NULL (make acpi_device_unregister() clear the device nodes' ACPI handles for that check to work). Finally, observe that acpi_os_hotplug_execute() actually can fail, in which case its caller ought to free memory allocated for the context object to prevent leaks from happening. It also needs to run put_device() on the device node that it ran get_device() on previously in that case. Modify the code accordingly. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Yinghai Lu <yinghai@kernel.org>
2013-02-13 14:36:47 +01:00
ACPI / hotplug: Fix concurrency issues and memory leaks This changeset is aimed at fixing a few different but related problems in the ACPI hotplug infrastructure. First of all, since notify handlers may be run in parallel with acpi_bus_scan(), acpi_bus_trim() and acpi_bus_hot_remove_device() and some of them are installed for ACPI handles that have no struct acpi_device objects attached (i.e. before those objects are created), those notify handlers have to take acpi_scan_lock to prevent races from taking place (e.g. a struct acpi_device is found to be present for the given ACPI handle, but right after that it is removed by acpi_bus_trim() running in parallel to the given notify handler). Moreover, since some of them call acpi_bus_scan() and acpi_bus_trim(), this leads to the conclusion that acpi_scan_lock should be acquired by the callers of these two funtions rather by these functions themselves. For these reasons, make all notify handlers that can handle device addition and eject events take acpi_scan_lock and remove the acpi_scan_lock locking from acpi_bus_scan() and acpi_bus_trim(). Accordingly, update all of their users to make sure that they are always called under acpi_scan_lock. Furthermore, since eject operations are carried out asynchronously with respect to the notify events that trigger them, with the help of acpi_bus_hot_remove_device(), even if notify handlers take the ACPI scan lock, it still is possible that, for example, acpi_bus_trim() will run between acpi_bus_hot_remove_device() and the notify handler that scheduled its execution and that acpi_bus_trim() will remove the device node passed to acpi_bus_hot_remove_device() for ejection. In that case, the struct acpi_device object obtained by acpi_bus_hot_remove_device() will be invalid and not-so-funny things will ensue. To protect agaist that, make the users of acpi_bus_hot_remove_device() run get_device() on ACPI device node objects that are about to be passed to it and make acpi_bus_hot_remove_device() run put_device() on them and check if their ACPI handles are not NULL (make acpi_device_unregister() clear the device nodes' ACPI handles for that check to work). Finally, observe that acpi_os_hotplug_execute() actually can fail, in which case its caller ought to free memory allocated for the context object to prevent leaks from happening. It also needs to run put_device() on the device node that it ran get_device() on previously in that case. Modify the code accordingly. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Yinghai Lu <yinghai@kernel.org>
2013-02-13 14:36:47 +01:00
ACPI / hotplug: Fix concurrency issues and memory leaks This changeset is aimed at fixing a few different but related problems in the ACPI hotplug infrastructure. First of all, since notify handlers may be run in parallel with acpi_bus_scan(), acpi_bus_trim() and acpi_bus_hot_remove_device() and some of them are installed for ACPI handles that have no struct acpi_device objects attached (i.e. before those objects are created), those notify handlers have to take acpi_scan_lock to prevent races from taking place (e.g. a struct acpi_device is found to be present for the given ACPI handle, but right after that it is removed by acpi_bus_trim() running in parallel to the given notify handler). Moreover, since some of them call acpi_bus_scan() and acpi_bus_trim(), this leads to the conclusion that acpi_scan_lock should be acquired by the callers of these two funtions rather by these functions themselves. For these reasons, make all notify handlers that can handle device addition and eject events take acpi_scan_lock and remove the acpi_scan_lock locking from acpi_bus_scan() and acpi_bus_trim(). Accordingly, update all of their users to make sure that they are always called under acpi_scan_lock. Furthermore, since eject operations are carried out asynchronously with respect to the notify events that trigger them, with the help of acpi_bus_hot_remove_device(), even if notify handlers take the ACPI scan lock, it still is possible that, for example, acpi_bus_trim() will run between acpi_bus_hot_remove_device() and the notify handler that scheduled its execution and that acpi_bus_trim() will remove the device node passed to acpi_bus_hot_remove_device() for ejection. In that case, the struct acpi_device object obtained by acpi_bus_hot_remove_device() will be invalid and not-so-funny things will ensue. To protect agaist that, make the users of acpi_bus_hot_remove_device() run get_device() on ACPI device node objects that are about to be passed to it and make acpi_bus_hot_remove_device() run put_device() on them and check if their ACPI handles are not NULL (make acpi_device_unregister() clear the device nodes' ACPI handles for that check to work). Finally, observe that acpi_os_hotplug_execute() actually can fail, in which case its caller ought to free memory allocated for the context object to prevent leaks from happening. It also needs to run put_device() on the device node that it ran get_device() on previously in that case. Modify the code accordingly. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Yinghai Lu <yinghai@kernel.org>
2013-02-13 14:36:47 +01:00
ACPI / hotplug: Fix concurrency issues and memory leaks This changeset is aimed at fixing a few different but related problems in the ACPI hotplug infrastructure. First of all, since notify handlers may be run in parallel with acpi_bus_scan(), acpi_bus_trim() and acpi_bus_hot_remove_device() and some of them are installed for ACPI handles that have no struct acpi_device objects attached (i.e. before those objects are created), those notify handlers have to take acpi_scan_lock to prevent races from taking place (e.g. a struct acpi_device is found to be present for the given ACPI handle, but right after that it is removed by acpi_bus_trim() running in parallel to the given notify handler). Moreover, since some of them call acpi_bus_scan() and acpi_bus_trim(), this leads to the conclusion that acpi_scan_lock should be acquired by the callers of these two funtions rather by these functions themselves. For these reasons, make all notify handlers that can handle device addition and eject events take acpi_scan_lock and remove the acpi_scan_lock locking from acpi_bus_scan() and acpi_bus_trim(). Accordingly, update all of their users to make sure that they are always called under acpi_scan_lock. Furthermore, since eject operations are carried out asynchronously with respect to the notify events that trigger them, with the help of acpi_bus_hot_remove_device(), even if notify handlers take the ACPI scan lock, it still is possible that, for example, acpi_bus_trim() will run between acpi_bus_hot_remove_device() and the notify handler that scheduled its execution and that acpi_bus_trim() will remove the device node passed to acpi_bus_hot_remove_device() for ejection. In that case, the struct acpi_device object obtained by acpi_bus_hot_remove_device() will be invalid and not-so-funny things will ensue. To protect agaist that, make the users of acpi_bus_hot_remove_device() run get_device() on ACPI device node objects that are about to be passed to it and make acpi_bus_hot_remove_device() run put_device() on them and check if their ACPI handles are not NULL (make acpi_device_unregister() clear the device nodes' ACPI handles for that check to work). Finally, observe that acpi_os_hotplug_execute() actually can fail, in which case its caller ought to free memory allocated for the context object to prevent leaks from happening. It also needs to run put_device() on the device node that it ran get_device() on previously in that case. Modify the code accordingly. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Yinghai Lu <yinghai@kernel.org>
2013-02-13 14:36:47 +01:00
ACPI / drivers: replace acpi_probe_lock spinlock with mutex Commit e647b532275b ("ACPI: Add early device probing infrastructure") introduced code that allows inserting driver specific struct acpi_probe_entry probe entries into ACPI linker sections (one per-subsystem, eg irqchip, clocksource) that are then walked to retrieve the data and function hooks required to probe the respective kernel components. Probing for all entries in a section is triggered through the __acpi_probe_device_table() function, that in turn, according to the table ID a given probe entry reports parses the table with the function retrieved from the respective section structures (ie struct acpi_probe_entry). Owing to the current ACPI table parsing implementation, the __acpi_probe_device_table() function has to share global variables with the acpi_match_madt() function, so in order to guarantee mutual exclusion locking is required between the two functions. Current kernel code implements the locking through the acpi_probe_lock spinlock; this has the side effect of requiring all code called within the lock (ie struct acpi_probe_entry.probe_{table/subtbl} hooks) not to sleep. However, kernel subsystems that make use of the early probing infrastructure are relying on kernel APIs that may sleep (eg irq_domain_alloc_fwnode(), among others) in the function calls pointed at by struct acpi_probe_entry.{probe_table/subtbl} entries (eg gic_v2_acpi_init()), which is a bug. Since __acpi_probe_device_table() is called from context that is allowed to sleep the acpi_probe_lock spinlock can be replaced with a mutex; this fixes the issue whilst still guaranteeing mutual exclusion. Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Fixes: e647b532275b (ACPI: Add early device probing infrastructure) Cc: 4.4+ <stable@vger.kernel.org> # 4.4+ Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-08-16 16:59:53 +01:00
ACPI / drivers: replace acpi_probe_lock spinlock with mutex Commit e647b532275b ("ACPI: Add early device probing infrastructure") introduced code that allows inserting driver specific struct acpi_probe_entry probe entries into ACPI linker sections (one per-subsystem, eg irqchip, clocksource) that are then walked to retrieve the data and function hooks required to probe the respective kernel components. Probing for all entries in a section is triggered through the __acpi_probe_device_table() function, that in turn, according to the table ID a given probe entry reports parses the table with the function retrieved from the respective section structures (ie struct acpi_probe_entry). Owing to the current ACPI table parsing implementation, the __acpi_probe_device_table() function has to share global variables with the acpi_match_madt() function, so in order to guarantee mutual exclusion locking is required between the two functions. Current kernel code implements the locking through the acpi_probe_lock spinlock; this has the side effect of requiring all code called within the lock (ie struct acpi_probe_entry.probe_{table/subtbl} hooks) not to sleep. However, kernel subsystems that make use of the early probing infrastructure are relying on kernel APIs that may sleep (eg irq_domain_alloc_fwnode(), among others) in the function calls pointed at by struct acpi_probe_entry.{probe_table/subtbl} entries (eg gic_v2_acpi_init()), which is a bug. Since __acpi_probe_device_table() is called from context that is allowed to sleep the acpi_probe_lock spinlock can be replaced with a mutex; this fixes the issue whilst still guaranteeing mutual exclusion. Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Fixes: e647b532275b (ACPI: Add early device probing infrastructure) Cc: 4.4+ <stable@vger.kernel.org> # 4.4+ Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-08-16 16:59:53 +01:00
ACPI / drivers: replace acpi_probe_lock spinlock with mutex Commit e647b532275b ("ACPI: Add early device probing infrastructure") introduced code that allows inserting driver specific struct acpi_probe_entry probe entries into ACPI linker sections (one per-subsystem, eg irqchip, clocksource) that are then walked to retrieve the data and function hooks required to probe the respective kernel components. Probing for all entries in a section is triggered through the __acpi_probe_device_table() function, that in turn, according to the table ID a given probe entry reports parses the table with the function retrieved from the respective section structures (ie struct acpi_probe_entry). Owing to the current ACPI table parsing implementation, the __acpi_probe_device_table() function has to share global variables with the acpi_match_madt() function, so in order to guarantee mutual exclusion locking is required between the two functions. Current kernel code implements the locking through the acpi_probe_lock spinlock; this has the side effect of requiring all code called within the lock (ie struct acpi_probe_entry.probe_{table/subtbl} hooks) not to sleep. However, kernel subsystems that make use of the early probing infrastructure are relying on kernel APIs that may sleep (eg irq_domain_alloc_fwnode(), among others) in the function calls pointed at by struct acpi_probe_entry.{probe_table/subtbl} entries (eg gic_v2_acpi_init()), which is a bug. Since __acpi_probe_device_table() is called from context that is allowed to sleep the acpi_probe_lock spinlock can be replaced with a mutex; this fixes the issue whilst still guaranteeing mutual exclusion. Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Fixes: e647b532275b (ACPI: Add early device probing infrastructure) Cc: 4.4+ <stable@vger.kernel.org> # 4.4+ Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-08-16 16:59:53 +01:00