1What: /dev/gpiochip[0-9]+ 2Date: November 2015 3KernelVersion: 4.4 4Contact: linux-gpio@vger.kernel.org 5Description: 6 The character device files /dev/gpiochip* are the interface 7 between GPIO chips and userspace. 8 9 The ioctl(2)-based ABI is defined and documented in 10 [include/uapi]<linux/gpio.h>. 11 12 The following file operations are supported: 13 14 open(2) 15 Currently the only useful flags are O_RDWR. 16 17 ioctl(2) 18 Initiate various actions. 19 20 See the inline documentation in [include/uapi]<linux/gpio.h> 21 for descriptions of all ioctls. 22 23 close(2) 24 Stops and free up the I/O contexts that was associated 25 with the file descriptor. 26 27Users: TBD 28