0001 What: /dev/gpiochip[0-9]+
0002 Date: November 2015
0003 KernelVersion: 4.4
0004 Contact: linux-gpio@vger.kernel.org
0005 Description:
0006 The character device files /dev/gpiochip* are the interface
0007 between GPIO chips and userspace.
0008
0009 The ioctl(2)-based ABI is defined and documented in
0010 [include/uapi]<linux/gpio.h>.
0011
0012 The following file operations are supported:
0013
0014 open(2)
0015 Currently the only useful flags are O_RDWR.
0016
0017 ioctl(2)
0018 Initiate various actions.
0019
0020 See the inline documentation in [include/uapi]<linux/gpio.h>
0021 for descriptions of all ioctls.
0022
0023 close(2)
0024 Stops and free up the I/O contexts that was associated
0025 with the file descriptor.
0026
0027 Users: TBD
