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,
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
24 - gpio_mouse: drivers/input/mouse/gpio_mouse.c is used to provide a mouse with
26   mouse cable and connect the wires to GPIO lines or solder a mouse connector
27   to the lines for a more permanent solution of this type.
29 - gpio-beeper: drivers/input/misc/gpio-beeper.c is used to provide a beep from
31   off/on, for an actual PWM waveform, see pwm-gpio below.)
33 - pwm-gpio: drivers/pwm/pwm-gpio.c is used to toggle a GPIO with a high
37 - extcon-gpio: drivers/extcon/extcon-gpio.c is used when you need to read an
41 - restart-gpio: drivers/power/reset/gpio-restart.c is used to restart/reboot
45 - poweroff-gpio: drivers/power/reset/gpio-poweroff.c is used to power the
50 - gpio-gate-clock: drivers/clk/clk-gpio.c is used to control a gated clock
53 - i2c-gpio: drivers/i2c/busses/i2c-gpio.c is used to drive an I2C bus
54   (two wires, SDA and SCL lines) by hammering (bitbang) two GPIO lines. It will
58 - spi_gpio: drivers/spi/spi-gpio.c is used to drive an SPI bus (variable number
59   of wires, at least SCK and optionally MISO, MOSI and chip select lines) using
65 - w1-gpio: drivers/w1/masters/w1-gpio.c is used to drive a one-wire bus using
69 - gpio-fan: drivers/hwmon/gpio-fan.c is used to control a fan for cooling the
71   presenting all the right in-kernel and sysfs interfaces to make your system
74 - gpio-regulator: drivers/regulator/gpio-regulator.c is used to control a
78 - gpio-wdt: drivers/watchdog/gpio_wdt.c is used to provide a watchdog timer
80   it from 1-to-0-to-1. If that hardware does not receive its "ping"
83 - gpio-nand: drivers/mtd/nand/raw/gpio.c is used to connect a NAND flash chip
84   to a set of simple GPIO lines: RDY, NCE, ALE, CLE, NWP. It interacts with the
88 - ps2-gpio: drivers/input/serio/ps2-gpio.c is used to drive a PS/2 (IBM) serio
93 - cec-gpio: drivers/media/platform/cec-gpio/ is used to interact with a CEC
97 - gpio-charger: drivers/power/supply/gpio-charger.c is used if you need to do
98   battery charging and all you have to go by to check the presence of the
104 - gpio-mux: drivers/mux/gpio.c is used for controlling a multiplexer using
107   some SoC-external entities, such as different components on a PCB that
113 MTD NOR flash has add-ons for extra GPIO lines too, though the address bus is
116 Use those instead of talking directly to the GPIOs from userspace; they
119 speed up your embedded hacking in particular by providing ready-made components.