mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-26 10:49:33 +00:00
![Linus Walleij](/assets/img/avatar_default.png)
Put in some documentation for the new character device ABI so we can properly etch it in stone. Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
26 lines
653 B
Text
26 lines
653 B
Text
What: /dev/gpiochip[0-9]+
|
|
Date: November 2015
|
|
KernelVersion: 4.4
|
|
Contact: linux-gpio@vger.kernel.org
|
|
Description:
|
|
The character device files /dev/gpiochip* are the interface
|
|
between GPIO chips and userspace.
|
|
|
|
The ioctl(2)-based ABI is defined and documented in
|
|
[include/uapi]<linux/gpio.h>.
|
|
|
|
The following file operations are supported:
|
|
|
|
open(2)
|
|
Currently the only useful flags are O_RDWR.
|
|
|
|
ioctl(2)
|
|
Initiate various actions.
|
|
See the inline documentation in [include/uapi]<linux/gpio.h>
|
|
for descriptions of all ioctls.
|
|
|
|
close(2)
|
|
Stops and free up the I/O contexts that was associated
|
|
with the file descriptor.
|
|
|
|
Users: TBD
|