linux/Documentation/zh_CN
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
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arm
arm64 Documentation:Update Documentation/zh_CN/arm64/memory.txt 2015-04-04 15:20:26 +02:00
filesystems
video4linux
CodingStyle
HOWTO
IRQ.txt
SecurityBugs
SubmittingDrivers
SubmittingPatches
basic_profiling.txt
email-clients.txt
gpio.txt gpio: remove gpiod_sysfs_set_active_low 2015-05-12 10:46:53 +02:00
io_ordering.txt
magic-number.txt
oops-tracing.txt
sparse.txt
stable_api_nonsense.txt
stable_kernel_rules.txt
volatile-considered-harmful.txt