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 in 10 [include/uapi]<linux/gpio.h> and documented in 11 Documentation/userspace-api/gpio/chardev.rst. 12 13 The following file operations are supported: 14 15 open(2) 16 Currently the only useful flags are O_RDWR. 17 18 ioctl(2) 19 Initiate various actions. 20 21 See Documentation/userspace-api/gpio/chardev.rst 22 for a description of all ioctls. 23 24 close(2) 25 Stops and free up the I/O contexts that was associated 26 with the file descriptor. 27 28Users: TBD 29