driver-api/gpio/drivers-on-gpio.rst

6 the right in-kernel and userspace APIs/ABIs for the job, and that these
10 - leds-gpio: drivers/leds/leds-gpio.c will handle LEDs connected to  GPIO
13 - ledtrig-gpio: drivers/leds/trigger/ledtrig-gpio.c will provide a LED trigger,
14   i.e. a LED will turn on/off in response to a GPIO line going high or low
15   (and that LED may in turn use the leds-gpio as per above).
17 - gpio-keys: drivers/input/keyboard/gpio_keys.c is used when your GPIO line
20 - gpio-keys-polled: drivers/input/keyboard/gpio_keys_polled.c is used when your
21   GPIO line cannot generate interrupts, so it needs to be periodically polled
24 - gpio_mouse: drivers/input/mouse/gpio_mouse.c is used to provide a mouse with
29 - gpio-beeper: drivers/input/misc/gpio-beeper.c is used to provide a beep from
30   an external speaker connected to a GPIO line.
32 - extcon-gpio: drivers/extcon/extcon-gpio.c is used when you need to read an
33   external connector status, such as a headset line for an audio driver or an
36 - restart-gpio: drivers/power/reset/gpio-restart.c is used to restart/reboot
37   the system by pulling a GPIO line and will register a restart handler so
40 - poweroff-gpio: drivers/power/reset/gpio-poweroff.c is used to power the
41   system down by pulling a GPIO line and will register a pm_power_off()
42   callback so that userspace can issue the right system call to power down the
45 - gpio-gate-clock: drivers/clk/clk-gpio.c is used to control a gated clock
48 - i2c-gpio: drivers/i2c/busses/i2c-gpio.c is used to drive an I2C bus
53 - spi_gpio: drivers/spi/spi-gpio.c is used to drive an SPI bus (variable number
60 - w1-gpio: drivers/w1/masters/w1-gpio.c is used to drive a one-wire bus using
61   a GPIO line, integrating with the W1 subsystem and handling devices on
64 - gpio-fan: drivers/hwmon/gpio-fan.c is used to control a fan for cooling the
65   system, connected to a GPIO line (and optionally a GPIO alarm line),
66   presenting all the right in-kernel and sysfs interfaces to make your system
69 - gpio-regulator: drivers/regulator/gpio-regulator.c is used to control a
70   regulator providing a certain voltage by pulling a GPIO line, integrating
73 - gpio-wdt: drivers/watchdog/gpio_wdt.c is used to provide a watchdog timer
74   that will periodically "ping" a hardware connected to a GPIO line by toggling
75   it from 1-to-0-to-1. If that hardware does not receive its "ping"
78 - gpio-nand: drivers/mtd/nand/raw/gpio.c is used to connect a NAND flash chip
83 - ps2-gpio: drivers/input/serio/ps2-gpio.c is used to drive a PS/2 (IBM) serio
84   bus, data and clock line, by bit banging two GPIO lines. It will appear as
88 - cec-gpio: drivers/media/platform/cec-gpio/ is used to interact with a CEC
92 - gpio-charger: drivers/power/supply/gpio-charger.c is used if you need to do
99 - gpio-mux: drivers/mux/gpio.c is used for controlling a multiplexer using
102   some SoC-external entities, such as different components on a PCB that
108 MTD NOR flash has add-ons for extra GPIO lines too, though the address bus is
114 speed up your embedded hacking in particular by providing ready-made components.