alistair23-linux/Documentation/gpio
Johan Hovold 166a85e442 gpio: remove gpiod_sysfs_set_active_low
Remove gpiod_sysfs_set_active_low (and gpio_sysfs_set_active_low) which
allowed code to change the polarity of a gpio line even after it had
been exported through sysfs.

Drivers should not care, and generally does not know, about gpio-line
polarity which is a hardware feature that needs to be described by
firmware.

It is currently possible to define gpio-line polarity in device-tree and
acpi firmware or using platform data. Userspace can also change the
polarity through sysfs.

Note that drivers using the legacy gpio interface could still use
GPIOF_ACTIVE_LOW to change the polarity before exporting the gpio.

There are no in-kernel users of this interface.

Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Harry Wei <harryxiyou@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: linux-doc@vger.kernel.org
Cc: linux-kernel@zh-kernel.org
Cc: linux-arch@vger.kernel.org
Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-05-12 10:46:53 +02:00
..
00-INDEX
board.txt Documentation: gpio: Update ACPI part of the document to mention _DSD 2015-04-04 15:20:27 +02:00
consumer.txt extend documentation for gpiod_set_array() functions 2015-03-09 17:38:49 +01:00
driver.txt gpio: rename gpio_lock_as_irq to gpiochip_lock_as_irq 2014-10-28 17:30:59 +01:00
gpio-legacy.txt gpio: remove gpiod_sysfs_set_active_low 2015-05-12 10:46:53 +02:00
gpio.txt
sysfs.txt gpio: remove gpiod_sysfs_set_active_low 2015-05-12 10:46:53 +02:00