This is the latest (main) BeagleBoard documentation. If you are looking for stable releases, use the drop-down menu on the bottom-left and select the desired version.

Function rc_gpio_init

Function Documentation

int rc_gpio_init(int chip, int pin, int handle_flags)

Configures a gpio pin as input or output.

This configures the pin by making a gpio handle request to the character device driver. It accepts the same gpio handle request flags as defined in <linux/gpio.h>

  • GPIOHANDLE_REQUEST_INPUT

  • GPIOHANDLE_REQUEST_OUTPUT

  • GPIOHANDLE_REQUEST_ACTIVE_LOW

  • GPIOHANDLE_REQUEST_OPEN_DRAIN

  • GPIOHANDLE_REQUEST_OPEN_SOURCE

Obviously the INPUT and OUTPUT flags cannot be used at the same time. If you don’t know what the other flags mean just stick with INPUT and OUTPUT modes, that covers 99% of use cases.

Parameters

  • chip – [in] The chip number, /dev/gpiochipX

  • pin – [in] The pin ID

  • handle_flags – [in] The handle flags

Returns

0 on success or -1 on failure.