linux/include
Jarkko Nikula 5853b22d96 i2c: core: Add function for finding the bus speed from ACPI, take 2
ACPI 5 specification doesn't have property for the I2C bus speed but
I2cSerialBus resource descriptor which define each controller-slave
connection define the maximum speed supported by that connection.

Thus finding the maximum safe speed for the bus is to walk through all
I2cSerialBus resources that are associated to I2C controller and use the
speed of slowest connection.

Add function i2c_acpi_find_bus_speed() to the i2c-core that adapter
drivers can call prior registering itself to core.

This implies two-step walk through the I2cSerialBus resources: call to
i2c_acpi_find_bus_speed() does the first scan and finds the safe bus
speed that adapter drivers can set up. Adapter driver registration does
the second scan when i2c-core creates the I2C slaves by calling the
i2c_acpi_register_devices(). In that way the bus speed is set in case
slave device probe gets called during registration and does communication.

Previous version commit 55d38d060e ("i2c: core: Add function for finding
the bus speed from ACPI") got reverted due merge conflicts from
commit 525e6fabea ("i2c / ACPI: add support for ACPI reconfigure
notifications").

This version is a bit bigger than previous version but is still sharing
the lowest and complicated part of I2cSerialBus lookup routines with the
existing code.

Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
History 2016-08-26 00:42:10 +02:00
..
acpi treewide: replace obsolete _refok by __ref 2016-08-02 17:31:41 -04:00
asm-generic locking/qrwlock: Fix write unlock bug on big endian systems 2016-08-10 14:13:27 +02:00
clocksource clocksource/drivers/sp804: Convert init function to return error 2016-06-28 10:19:30 +02:00
crypto A number of improvements for the /dev/random driver; the most 2016-07-27 15:11:55 -07:00
drm Merge branch 'drm-next-4.8' of git://people.freedesktop.org/~agd5f/linux into drm-next 2016-08-08 16:45:33 +10:00
dt-bindings ARM: DT updates for v4.8 2016-08-01 18:37:45 -04:00
keys KEYS: Strip trailing spaces 2016-06-14 10:29:44 +01:00
kvm KVM/ARM Changes for v4.8 - Take 2 2016-08-04 13:59:56 +02:00
linux i2c: core: Add function for finding the bus speed from ACPI, take 2 2016-08-26 00:42:10 +02:00
math-emu math-emu: fix floating-point to integer overflow detection 2014-01-07 18:36:24 -06:00
media dma-mapping: use unsigned long for dma_attrs 2016-08-04 08:50:07 -04:00
memory ddr: add LPDDR2 data from JESD209-2 2012-05-02 00:04:06 -07:00
misc cxl: Add cxl_check_and_switch_mode() API to switch bi-modal cards 2016-07-14 20:28:11 +10:00
net Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2016-08-17 17:26:58 -07:00
pcmcia pcmcia/ds.h: introduce helper for pcmcia_driver module boilerplate 2013-03-15 12:26:03 -07:00
ras tracing, RAS: Cleanup on __get_str() usage 2016-07-15 15:51:16 -04:00
rdma Second round of merge items for 4.8 2016-08-04 20:26:31 -04:00
rxrpc rxrpc: Static arrays of strings should be const char *const[] 2016-04-11 15:34:40 -04:00
scsi Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending 2016-08-04 20:04:37 -04:00
soc ARM: SoC driver updates for v4.8 2016-08-01 18:36:01 -04:00
sound Merge tag 'drm-for-v4.8' of git://people.freedesktop.org/~airlied/linux 2016-08-01 21:44:08 -04:00
target target: Fix ordered task CHECK_CONDITION early exception handling 2016-07-20 00:58:40 -07:00
trace Luiz Capitulino noticed that the tick_stop tracepoint wasn't being parsed 2016-08-09 10:34:09 -07:00
uapi Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2016-08-17 17:26:58 -07:00
video gpu: ipu-v3: ipu-dmfc: Use static DMFC FIFO allocation mechanism 2016-07-12 18:23:43 +02:00
xen dma-mapping: use unsigned long for dma_attrs 2016-08-04 08:50:07 -04:00
Kbuild UAPI: remove empty Kbuild files 2013-04-30 17:04:09 -07:00