OpenCloudOS-Kernel/Documentation/gpio
Alexandre Courbot ad824783fb gpio: better lookup method for platform GPIOs
Change the format of the platform GPIO lookup tables to make them less
confusing and improve lookup efficiency.

The previous format was a single linked-list that required to compare
the device name and function ID of every single GPIO defined for each
lookup. Switch that to a list of per-device tables, so that the lookup
can be done in two steps, omitting the GPIOs that are not relevant for a
particular device.

The matching rules are now defined as follows:
- The device name must match *exactly*, and can be NULL for GPIOs not
  assigned to a particular device,
- If the function ID in the lookup table is NULL, the con_id argument of
  gpiod_get() will not be used for lookup. However, if it is defined, it
  must match exactly.
- The index must always match.

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-12-09 14:05:51 +01:00
..
00-INDEX Documentation: gpiolib: add 00-INDEX file 2013-12-03 13:10:48 +01:00
board.txt gpio: better lookup method for platform GPIOs 2013-12-09 14:05:51 +01:00
consumer.txt Documentation: gpiolib: document new interface 2013-11-25 09:02:30 +01:00
driver.txt Documentation: gpiolib: document new interface 2013-11-25 09:02:30 +01:00
gpio-legacy.txt Documentation: gpiolib: document new interface 2013-11-25 09:02:30 +01:00
gpio.txt Documentation: gpiolib: document new interface 2013-11-25 09:02:30 +01:00
sysfs.txt Documentation: gpiolib: document new interface 2013-11-25 09:02:30 +01:00