aboutsummaryrefslogtreecommitdiffstats
path: root/Documentation/ABI/testing/gpio-cdev
blob: 66bdcd188b6c98320ae56b1dcf73585eb891fe91 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
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