18c2ecf20Sopenharmony_ciWhat: /dev/gpiochip[0-9]+ 28c2ecf20Sopenharmony_ciDate: November 2015 38c2ecf20Sopenharmony_ciKernelVersion: 4.4 48c2ecf20Sopenharmony_ciContact: linux-gpio@vger.kernel.org 58c2ecf20Sopenharmony_ciDescription: 68c2ecf20Sopenharmony_ci The character device files /dev/gpiochip* are the interface 78c2ecf20Sopenharmony_ci between GPIO chips and userspace. 88c2ecf20Sopenharmony_ci 98c2ecf20Sopenharmony_ci The ioctl(2)-based ABI is defined and documented in 108c2ecf20Sopenharmony_ci [include/uapi]<linux/gpio.h>. 118c2ecf20Sopenharmony_ci 128c2ecf20Sopenharmony_ci The following file operations are supported: 138c2ecf20Sopenharmony_ci 148c2ecf20Sopenharmony_ci open(2) 158c2ecf20Sopenharmony_ci Currently the only useful flags are O_RDWR. 168c2ecf20Sopenharmony_ci 178c2ecf20Sopenharmony_ci ioctl(2) 188c2ecf20Sopenharmony_ci Initiate various actions. 198c2ecf20Sopenharmony_ci 208c2ecf20Sopenharmony_ci See the inline documentation in [include/uapi]<linux/gpio.h> 218c2ecf20Sopenharmony_ci for descriptions of all ioctls. 228c2ecf20Sopenharmony_ci 238c2ecf20Sopenharmony_ci close(2) 248c2ecf20Sopenharmony_ci Stops and free up the I/O contexts that was associated 258c2ecf20Sopenharmony_ci with the file descriptor. 268c2ecf20Sopenharmony_ci 278c2ecf20Sopenharmony_ciUsers: TBD 28