Lines Matching refs:GPIO

1 GPIO Sysfs Interface for Userspace
6 debugfs interface, since it provides control over GPIO direction and
11 know for example that GPIO #23 controls the write protect line used to
13 may need to temporarily remove that protection, first importing a GPIO,
15 the write protection. In normal use, GPIO #23 would never be touched,
19 userspace GPIO can be used to determine system configuration data that
21 GPIO drivers could be all that the system really needs.
36    -	GPIO controllers ("gpio_chip" instances).
45 		a GPIO to userspace by writing its number to this file.
48 		for GPIO #19, if that's not requested by kernel code.
55 GPIO signals have paths like /sys/class/gpio/gpio42/ (for GPIO #42)
64 		configure the GPIO as an output with that initial value.
67 		doesn't support changing the direction of a GPIO, or
69 		allow userspace to reconfigure this GPIO's direction.
71 	"value" ... reads as either 0 (low) or 1 (high). If the GPIO
99 GPIO controllers have paths like /sys/class/gpio/gpiochip42/ (for the
105     	"base" ... same as N, the first GPIO managed by this chip
116 the correct GPIO number to use for a given signal.
124 	/* export the GPIO to userspace */
130 	/* create a sysfs link to an exported GPIO node */
134 After a kernel driver requests a GPIO, it may only be made available in
143 After the GPIO has been exported, gpiod_export_link() allows creating
144 symlinks from elsewhere in sysfs to the GPIO sysfs node. Drivers can