Fix a regression when creating a file over a whiteout. The new
file/directory needs to use the current fsuid/fsgid, not the ones from the
mounter's credentials.
The refcounting is a bit tricky: prepare_creds() sets an original refcount,
override_creds() gets one more, which revert_cred() drops. So
1) we need to expicitly put the mounter's credentials when overriding
with the updated one
2) we need to put the original ref to the updated creds (and this can
safely be done before revert_creds(), since we'll still have the ref
from override_creds()).
Reported-by: Stephen Smalley <sds@tycho.nsa.gov>
Fixes: 3fe6e52f06 ("ovl: override creds with the ones from the superblock mounter")
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Creating the data connection at probe time makes it impossible to
support multiple inserted camera modules as they would all try to
establish a data connection to the same CPort on the AP side. Create and
destroy the data connection when configuring the streams instead, as a
single module can be streaming at a time.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Gjorgji Rosikopulos <grosikopulos@mm-sol.com>
Tested-by: Gjorgji Rosikopulos <grosikopulos@mm-sol.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
When the module is in the configured state, an attempt to change the
configuration must first tear down the data connection to update its
parameters, as the APB1 bridge doesn't support modifying the CSI
transmitter configuration when it is already started.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Gjorgji Rosikopulos <grosikopulos@mm-sol.com>
Tested-by: Gjorgji Rosikopulos <grosikopulos@mm-sol.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
When the camera pipeline can't be configured due to a failure of one of
the components (failure to start the CSI transmitter for instance),
components that have already been setup for video streaming need to be
set back to a quiescient state. This is especially important to ensure
that a stream configuration failure won't keep the UniPro links in high
speed mode forever.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Gjorgji Rosikopulos <grosikopulos@mm-sol.com>
Tested-by: Gjorgji Rosikopulos <grosikopulos@mm-sol.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Register iommu_ops at the end of successful probe instead of doing that
unconditionally. This makes Exynos IOMMU driver ready for deferred probe
caused by not-yet-available clocks.
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Make clock preparation together with clk_enable(). This way inactive
SYSMMU controllers will not keep clocks prepared all the time.
This change allows more fine graded power management in the future.
All the code assumes that clock management doesn't fail, so guard
clock_prepare_enable() it with BUG_ON().
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
If SYSMMU controller is not active, there is no point in enabling master's
clock just for doing the the of internal state. This patch moves enabling
that clock to the block which actually does the register access.
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
This patch reworks driver probe code to propagate error codes from
clk_get() operation. This will allow to properly handle deferred probe
in the future.
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Debugfs' open_proxy_open(), the ->open() installed at all inodes created
through debugfs_create_file_unsafe(),
- grabs a reference to the original file_operations instance passed to
debugfs_create_file_unsafe() via fops_get(),
- installs it at the file's ->f_op by means of replace_fops()
- and calls fops_put() on it.
Since the semantics of replace_fops() are such that the reference's
ownership is transferred, the subsequent fops_put() will result in a double
release when the file is eventually closed.
Currently, this is not an issue since fops_put() basically does a
module_put() on the file_operations' ->owner only and there don't exist any
modules calling debugfs_create_file_unsafe() yet. This is expected to
change in the future though, c.f. commit c646880814 ("debugfs: add
support for self-protecting attribute file fops").
Remove the call to fops_put() from open_proxy_open().
Fixes: 9fd4dcece4 ("debugfs: prevent access to possibly dead
file_operations at file open")
Signed-off-by: Nicolai Stange <nicstange@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Debugfs' full_proxy_open(), the ->open() installed at all inodes created
through debugfs_create_file(),
- grabs a reference to the original struct file_operations instance passed
to debugfs_create_file(),
- dynamically allocates a proxy struct file_operations instance wrapping
the original
- and installs this at the file's ->f_op.
Afterwards, it calls the original ->open() and passes its return value back
to the VFS layer.
Now, if that return value indicates failure, the VFS layer won't ever call
->release() and thus, neither the reference to the original file_operations
nor the memory for the proxy file_operations will get released, i.e. both
are leaked.
Upon failure of the original fops' ->open(), undo the proxy installation.
That is:
- Set the struct file ->f_op to what it had been when full_proxy_open()
was entered.
- Drop the reference to the original file_operations.
- Free the memory holding the proxy file_operations.
Fixes: 49d200deaa ("debugfs: prevent access to removed files' private
data")
Signed-off-by: Nicolai Stange <nicstange@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Since commit 49d200deaa ("debugfs: prevent access to removed files'
private data"), a debugfs file's file_operations methods get proxied
through lifetime aware wrappers.
However, only a certain subset of the file_operations members is supported
by debugfs and ->mmap isn't among them -- it appears to be NULL from the
VFS layer's perspective.
This behaviour breaks the /sys/kernel/debug/kcov file introduced
concurrently with commit 5c9a8750a6 ("kernel: add kcov code coverage").
Since that file never gets removed, there is no file removal race and thus,
a lifetime checking proxy isn't needed.
Avoid the proxying for /sys/kernel/debug/kcov by creating it via
debugfs_create_file_unsafe() rather than debugfs_create_file().
Fixes: 49d200deaa ("debugfs: prevent access to removed files' private data")
Fixes: 5c9a8750a6 ("kernel: add kcov code coverage")
Reported-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Nicolai Stange <nicstange@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In rare cases it is possible for s_flags & MS_RDONLY to be set but
MNT_READONLY to be clear. This starting combination can cause
fs_fully_visible to fail to ensure that the new mount is readonly.
Therefore force MNT_LOCK_READONLY in the new mount if MS_RDONLY
is set on the source filesystem of the mount.
In general both MS_RDONLY and MNT_READONLY are set at the same for
mounts so I don't expect any programs to care. Nor do I expect
MS_RDONLY to be set on proc or sysfs in the initial user namespace,
which further decreases the likelyhood of problems.
Which means this change should only affect system configurations by
paranoid sysadmins who should welcome the additional protection
as it keeps people from wriggling out of their policies.
Cc: stable@vger.kernel.org
Fixes: 8c6cf9cc82 ("mnt: Modify fs_fully_visible to deal with locked ro nodev and atime")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
In commit <8bf478163e> ("iommu/vt-d: Split up iommu->domains array"), it
it splits iommu->domains in two levels. Each first level contains 256
entries of second level. In case of the ndomains is exact a multiple of
256, it would have one more extra first level entry for current
implementation.
This patch refines this calculation to reduce the extra first level entry.
Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Removal of IOMMU driver cannot be done reliably, so Exynos IOMMU driver
doesn't support this operation. It is essential for system operation, so
it makes sense to prevent unbinding by disabling bind/unbind sysfs
feature for SYSMMU controller driver to avoid kernel ops or trashing
memory caused by such operation.
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
CC: stable@vger.kernel.org # v4.2+
Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Use the upper_32_bits() macro instead of the four line equivalent that
triggers a GCC warning on 32 bits x86:
drivers/gpu/drm/vmwgfx/vmwgfx_cmdbuf.c: In function 'vmw_cmdbuf_header_submit':
drivers/gpu/drm/vmwgfx/vmwgfx_cmdbuf.c:297:25: warning: right shift count >= width of type [-Wshift-count-overflow]
val = (header->handle >> 32);
^
And use the lower_32_bits() macro instead of and-ing with a 32 bits
mask.
Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Acked-by: Joe Perches <joe@perches.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1457000770-2317-1-git-send-email-pebolle@tiscali.nl
Rather than wait until we observe the lock being free (which might never
happen), we can also return from spin_unlock_wait if we observe that the
lock is now held by somebody else, which implies that it was unlocked
but we just missed seeing it in that state.
Furthermore, in such a scenario there is no longer a need to write back
the value that we loaded, since we know that there has been a lock
hand-off, which is sufficient to publish any stores prior to the
unlock_wait because the ARm architecture ensures that a Store-Release
instruction is multi-copy atomic when observed by a Load-Acquire
instruction.
The litmus test is something like:
AArch64
{
0:X1=x; 0:X3=y;
1:X1=y;
2:X1=y; 2:X3=x;
}
P0 | P1 | P2 ;
MOV W0,#1 | MOV W0,#1 | LDAR W0,[X1] ;
STR W0,[X1] | STLR W0,[X1] | LDR W2,[X3] ;
DMB SY | | ;
LDR W2,[X3] | | ;
exists
(0:X2=0 /\ 2:X0=1 /\ 2:X2=0)
where P0 is doing spin_unlock_wait, P1 is doing spin_unlock and P2 is
doing spin_lock.
Signed-off-by: Will Deacon <will.deacon@arm.com>
nft_genmask_cur has already done left-shift operator on the gencursor,
so there's no need to do left-shift operator on it again.
Fixes: ea4bd995b0 ("netfilter: nf_tables: add transaction helper functions")
Cc: Patrick McHardy <kaber@trash.net>
Signed-off-by: Liping Zhang <liping.zhang@spreadtrum.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
When we add a nft rule like follows:
# nft add rule filter test tcp dport vmap {1: jump test}
-ELOOP error will be returned, and the anonymous set will be
destroyed.
But after that, nf_tables_abort will also try to remove the
element and destroy the set, which was already destroyed and
freed.
If we add a nft wrong rule, nft_tables_abort will do the cleanup
work rightly, so nf_tables_set_destroy call here is redundant and
wrong, remove it.
Signed-off-by: Liping Zhang <liping.zhang@spreadtrum.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Liping Zhang says:
"Users may add such a wrong nft rules successfully, which will cause an
endless jump loop:
# nft add rule filter test tcp dport vmap {1: jump test}
This is because before we commit, the element in the current anonymous
set is inactive, so osp->walk will skip this element and miss the
validate check."
To resolve this problem, this patch passes the generation mask to the
walk function through the iter container structure depending on the code
path:
1) If we're dumping the elements, then we have to check if the element
is active in the current generation. Thus, we check for the current
bit in the genmask.
2) If we're checking for loops, then we have to check if the element is
active in the next generation, as we're in the middle of a
transaction. Thus, we check for the next bit in the genmask.
Based on original patch from Liping Zhang.
Reported-by: Liping Zhang <liping.zhang@spreadtrum.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Tested-by: Liping Zhang <liping.zhang@spreadtrum.com>
We should check "i" is used as a dictionary or not, "binding" is already
checked before.
Signed-off-by: Liping Zhang <liping.zhang@spreadtrum.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
I forgot to move the kmem_cache_destroy into the exit path.
Fixes: 0c5366b3a8 ("netfilter: conntrack: use single slab cache)
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
rk_iommu_command() takes a struct rk_iommu and iterates over the slave
MMUs, so this is doubly wrong in that we're passing in the wrong pointer
and talking to MMUs that we shouldn't be.
Fixes: cd6438c5f8 ("iommu/rockchip: Reconstruct to support multi slaves")
Cc: stable@vger.kernel.org
Signed-off-by: John Keeping <john@metanate.com>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
AMD has more drivers will use ACPI to platform bus driver later,
all those devices need iommu support, for example: eMMC driver.
For latest AMD eMMC controller, it will utilize sdhci-acpi.c driver,
which will rely on platform bus to match device and driver, where we
will set 'dev' of struct platform_device as map_sg parameter passing
to iommu driver for DMA request, so the iommu-ops are needed on the
platform bus.
Signed-off-by: Wan Zongshun <Vincent.Wan@amd.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
In is_connected_ep, when custom_stop_condition is true, need to
return the correct paths instead of con which is 0.
Fixes: 6742064aef7f('ASoC: dapm: support user-defined stop condition in dai_get_connected_widgets')
Signed-off-by: Jeeja KP <jeeja.kp@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Use regulator_list_voltage_linear_range in rpm_smps_ldo_ops_fixed is
wrong because it is used for fixed regulator without any linear range.
The rpm_smps_ldo_ops_fixed is used for pm8941_lnldo which has fixed_uV
set and n_voltages = 1. In this case, regulator_list_voltage() can return
rdev->desc->fixed_uV without .list_voltage implementation.
Fixes: 3bfbb4d1a4 ("regulator: qcom_smd: add list_voltage callback")
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Since d16e0faab9 (iommu: Allow selecting page sizes per domain) the
iommu core demands the page size to be set per domain, otherwise any
mapping attempts will be dropped. Make sure to set a valid page size
for the etnaviv iommu.
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Use the peer record to distribute network errors rather than the transport
object (which I want to get rid of). An error from a particular peer
terminates all calls on that peer.
For future consideration:
(1) For ICMP-induced errors it might be worth trying to extract the RxRPC
header from the offending packet, if one is returned attached to the
ICMP packet, to better direct the error.
This may be overkill, though, since an ICMP packet would be expected
to be relating to the destination port, machine or network. RxRPC
ABORT and BUSY packets give notice at RxRPC level.
(2) To also abort connection-level communications (such as CHALLENGE
packets) where indicted by an error - but that requires some revamping
of the connection event handling first.
Signed-off-by: David Howells <dhowells@redhat.com>
Don't assume anything about the address in an ICMP packet in
rxrpc_error_report() as the address may not be IPv4 in future, especially
since we're just printing these details.
Signed-off-by: David Howells <dhowells@redhat.com>
Break MTU determination from ICMP out into its own function to reduce the
complexity of the error report handler.
Signed-off-by: David Howells <dhowells@redhat.com>
Rename rxrpc_UDP_error_report() to rxrpc_error_report() as it might get
called for something other than UDP.
Signed-off-by: David Howells <dhowells@redhat.com>
Rework peer object handling to use a hash table instead of a flat list and
to use RCU. Peer objects are no longer destroyed by passing them to a
workqueue to process, but rather are just passed to the RCU garbage
collector as kfree'able objects.
The hash function uses the local endpoint plus all the components of the
remote address, except for the RxRPC service ID. Peers thus represent a
UDP port on the remote machine as contacted by a UDP port on this machine.
The RCU read lock is used to handle non-creating lookups so that they can
be called from bottom half context in the sk_error_report handler without
having to lock the hash table against modification.
rxrpc_lookup_peer_rcu() *does* take a reference on the peer object as in
the future, this will be passed to a work item for error distribution in
the error_report path and this function will cease being used in the
data_ready path.
Creating lookups are done under spinlock rather than mutex as they might be
set up due to an external stimulus if the local endpoint is a server.
Captured network error messages (ICMP) are handled with respect to this
struct and MTU size and RTT are cached here.
Signed-off-by: David Howells <dhowells@redhat.com>
Return the raw key with no other processing so that the caller
can copy it or MPI parse it, etc.
The scope is to have only one ANS.1 parser for all RSA
implementations.
Update the RSA software implementation so that it does
the MPI conversion on top.
Signed-off-by: Tudor Ambarus <tudor-dan.ambarus@nxp.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The TFM object maintains the key for the CTR DRBG.
Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The CTR DRBG update function performs a full CTR AES operation including
the XOR with "plaintext" data. Hence, remove the XOR from the code and
use the CTR mode to do the XOR.
Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Hardware cipher implementation may require aligned buffers. All buffers
that potentially are processed with a cipher are now aligned.
Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The CTR DRBG derives its random data from the CTR that is encrypted with
AES.
This patch now changes the CTR DRBG implementation such that the
CTR AES mode is employed. This allows the use of steamlined CTR AES
implementation such as ctr-aes-aesni.
Unfortunately there are the following subtile changes we need to apply
when using the CTR AES mode:
- the CTR mode increments the counter after the cipher operation, but
the CTR DRBG requires the increment before the cipher op. Hence, the
crypto_inc is applied to the counter (drbg->V) once it is
recalculated.
- the CTR mode wants to encrypt data, but the CTR DRBG is interested in
the encrypted counter only. The full CTR mode is the XOR of the
encrypted counter with the plaintext data. To access the encrypted
counter, the patch uses a NULL data vector as plaintext to be
"encrypted".
Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Commit d86b8da04d ("arm64: spinlock: serialise spin_unlock_wait against
concurrent lockers") fixed spin_unlock_wait for LL/SC-based atomics under
the premise that the LSE atomics (in particular, the LDADDA instruction)
are indivisible.
Unfortunately, these instructions are only indivisible when used with the
-AL (full ordering) suffix and, consequently, the same issue can
theoretically be observed with LSE atomics, where a later (in program
order) load can be speculated before the write portion of the atomic
operation.
This patch fixes the issue by performing a CAS of the lock once we've
established that it's unlocked, in much the same way as the LL/SC code.
Fixes: d86b8da04d ("arm64: spinlock: serialise spin_unlock_wait against concurrent lockers")
Signed-off-by: Will Deacon <will.deacon@arm.com>
spin_is_locked has grown two very different use-cases:
(1) [The sane case] API functions may require a certain lock to be held
by the caller and can therefore use spin_is_locked as part of an
assert statement in order to verify that the lock is indeed held.
For example, usage of assert_spin_locked.
(2) [The insane case] There are two locks, where a CPU takes one of the
locks and then checks whether or not the other one is held before
accessing some shared state. For example, the "optimized locking" in
ipc/sem.c.
In the latter case, the sequence looks like:
spin_lock(&sem->lock);
if (!spin_is_locked(&sma->sem_perm.lock))
/* Access shared state */
and requires that the spin_is_locked check is ordered after taking the
sem->lock. Unfortunately, since our spinlocks are implemented using a
LDAXR/STXR sequence, the read of &sma->sem_perm.lock can be speculated
before the STXR and consequently return a stale value.
Whilst this hasn't been seen to cause issues in practice, PowerPC fixed
the same issue in 51d7d5205d ("powerpc: Add smp_mb() to
arch_spin_is_locked()") and, although we did something similar for
spin_unlock_wait in d86b8da04d ("arm64: spinlock: serialise
spin_unlock_wait against concurrent lockers") that doesn't actually take
care of ordering against local acquisition of a different lock.
This patch adds an smp_mb() to the start of our arch_spin_is_locked and
arch_spin_unlock_wait routines to ensure that the lock value is always
loaded after any other locks have been taken by the current CPU.
Reported-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
There is a problem in the non-devicetree PMU probing where some
probe functions may get the number of supported events through
smp_call_function_any() using the arm_pmu supported_cpus mask.
But at the time the probe function is called, the supported_cpus
mask is empty so the call fails. This patch makes sure the mask
is set before calling the init function rather than after.
Signed-off-by: Mark Salter <msalter@redhat.com>
Signed-off-by: Jeremy Linton <jeremy.linton@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
If USB cable is connected prior to boot, we don't get any interrupts
so we must manually check the VBUS state and report it during probe.
If we don't do it then USB controller will never know that peripheral
cable was connected till the user unplugs and replugs the cable.
Fixes: b7aad8e268 ("extcon: palmas: Add the support for VBUS detection by using GPIO")
Cc: stable@vger.kernel.org
Signed-off-by: Roger Quadros <rogerq@ti.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Replace the in order struct initialisation style with explicit field
style.
The Coccinelle semantic patch used to make this change is as follows:
@decl@
identifier i1,fld;
type T;
field list[n] fs;
@@
struct i1 {
fs
T fld;
...};
@@
identifier decl.i1,i2,decl.fld;
expression e;
position bad.p, bad.fix;
@@
struct i1 i2@p = { ...,
+ .fld = e
- e@fix
,...};
Also, removed some unnecessary comments.
Signed-off-by: Amitoj Kaur Chawla <amitoj1606@gmail.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Add Power Management Unit driver to handle power states of South Complex
devices on Intel Tangier. In the future it might be expanded to cover North
Complex devices as well.
With this driver the power state of the host controllers such as SPI, I2C,
UART, eMMC, and DMA would be managed.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: David Cohen <david.a.cohen@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mika Westerberg <mika.westerberg@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-pci@vger.kernel.org
Link: http://lkml.kernel.org/r/1465928985-12113-1-git-send-email-andriy.shevchenko@linux.intel.com
[ Minor readability edits. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
New headset mode of ALC891 for Dell.
This patch is supported Dell headset mode for ALC891.
It is only support I-phone type headset.
I think this function is only support for DELL.
This patch is test passed by Ubuntu team.
Signed-off-by: Kailang Yang <kailang@realtek.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
The gpio-event-mon is used from userspace as an example of how
to monitor GPIO line events. It will latch on to a certain
GPIO line on a certain gpiochip and print timestamped events
as they arrive.
Example output:
$ gpio-event-mon -n gpiochip2 -o 0 -r -f
Monitoring line 0 on gpiochip2
Initial line value: 1
GPIO EVENT 946685798487609863: falling edge
GPIO EVENT 946685798732482910: rising edge
GPIO EVENT 946685799115997314: falling edge
GPIO EVENT 946685799381469726: rising edge
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This adds an ABI for listening to events on GPIO lines.
The mechanism returns an anonymous file handle to a request
to listen to a specific offset on a specific gpiochip.
To fetch the stream of events from the file handle, userspace
simply reads an event.
- Events can be requested with the same flags as ordinary
handles, i.e. open drain or open source. An ioctl() call
GPIO_GET_LINEEVENT_IOCTL is issued indicating the desired
line.
- Events can be requested for falling edge events, rising
edge events, or both.
- All events are timestamped using the kernel real time
nanosecond timestamp (the same as is used by IIO).
- The supplied consumer label will appear in "lsgpio"
listings of the lines, and in /proc/interrupts as the
mechanism will request an interrupt from the gpio chip.
- Events are not supported on gpiochips that do not serve
interrupts (no legal .to_irq() call). The event interrupt
is threaded to avoid any realtime problems.
- It is possible to also directly read the current value
of the registered GPIO line by issuing the same
GPIOHANDLE_GET_LINE_VALUES_IOCTL as used by the
line handles. Setting the value is not supported: we
do not listen to events on output lines.
This ABI is strongly influenced by Industrial I/O and surpasses
the old sysfs ABI by providing proper precision timestamps,
making it possible to set flags like open drain, and put
consumer names on the GPIO lines.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The gpio-hammer is used from userspace as an example of how
to retrieve a GPIO handle for one or several GPIO lines and
hammer the outputs from low to high and back again. It will
pulse the selected lines once per second for a specified
number of times or indefinitely if no loop count is
supplied.
Example output:
$ gpio-hammer -n gpiochip0 -o5 -o6 -o7
Hammer lines [5, 6, 7] on gpiochip0, initial states: [1, 1, 1]
[-] [5: 0, 6: 0, 7: 0]
Tested-by: Michael Welling <mwelling@ieee.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This adds a userspace ABI for reading and writing GPIO lines.
The mechanism returns an anonymous file handle to a request
to read/write n offsets from a gpiochip. This file handle
in turn accepts two ioctl()s: one that reads and one that
writes values to the selected lines.
- Handles can be requested as input/output, active low,
open drain, open source, however when you issue a request
for n lines with GPIO_GET_LINEHANDLE_IOCTL, they must all
have the same flags, i.e. all inputs or all outputs, all
open drain etc. If a granular control of the flags for
each line is desired, they need to be requested
individually, not in a batch.
- The GPIOHANDLE_GET_LINE_VALUES_IOCTL read ioctl() can be
issued also to output lines to verify that the hardware
is in the expected state.
- It reads and writes up to GPIOHANDLES_MAX lines at once,
utilizing the .set_multiple() call in the driver if
possible, making the call efficient if several lines
can be written with a single register update.
The limitation of GPIOHANDLES_MAX to 64 lines is done under
the assumption that we may expect hardware that can issue a
transaction updating 64 bits at an instant but unlikely
anything larger than that.
ChangeLog v2->v3:
- Use gpiod_get_value_cansleep() so we support also slowpath
GPIO drivers.
- Fix up the UAPI docs kerneldoc.
- Allocate the anonymous fd last, so that the release
function don't get called until that point of something
fails. After this point, skip the errorpath.
ChangeLog v1->v2:
- Handle ioctl_compat() properly based on a similar patch
to the other ioctl() handling code.
- Use _IOWR() as we pass pointers both in and out of the
ioctl()
- Use kmalloc() and kfree() for the linehandled, do not
try to be fancy with devm_* it doesn't work the way I
thought.
- Fix const-correctness on the linehandle name field.
Acked-by: Michael Welling <mwelling@ieee.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
