relet / apu_gpio_lib

Userspace library to access APU2/3 gpios

APU2/3 GPIO access library

This is library for accessing the GPIO's of APU2/3 devices. Currently it supports accessing the GPIO's controlling the LED1,2,3, MODESW signal and SIMSWAP signal (apu3 only).

This library could be used as an example.

Required tools to build

• gcc
• cmake

How to compile

By default compiles statically linked library and some examples.

mkdir build
cd build
cmake ..
make

Example

After compilation. Examples are in dir build/example.

• blinky - it blinks the LED2 and LED3 on APU.
• simswap - changes the simswap pin value. Usage:
  • ./simswap - shows current pin state
  • ./simswap 1 - sets the simswap pin value to 1
  • ./simswap 0 - sets the simswap pin value to 0

Library API

Short API summary:

• const char *apu_gpio_version(void) - returns library version string
• int apu_gpio_init(void) - initializes the library and maps the gpio space
• int apu_gpio_get_dir(unsigned offset) - gets gpio direction (1 - out, 0 - in)
• int apu_gpio_set_dir(unsigned offset, unsigned direction) - sets gpio direction (1 - out, 0 - in)
• int apu_gpio_get_val(unsigned offset) - gets gpio state
• int apu_gpio_set_val(unsigned offset, unsigned value) - sets gpio value