RetroArch/led/rpi_led_driver.c

#include <stdio.h>
#include "led_driver.h"
#include "led_defines.h"

#include "configuration.h"
#include "verbosity.h"

typedef struct
{
    int setup[MAX_LEDS];
    int map[MAX_LEDS];
} rpiled_t;

static rpiled_t curins;
static rpiled_t *cur = &curins;

static void rpi_init(void)
{
    int i;
    settings_t *settings = config_get_ptr();
    RARCH_LOG("[LED]: rpi LED driver init\n");
    for(i=0;i<MAX_LEDS;i++) {
        cur->setup[i] = 0;
        cur->map[i] = settings->uints.led_map[i];
        RARCH_LOG("[LED]: rpi map[%d]=%d\n",i,cur->map[i]);
    }
}
static void rpi_free(void)
{
    RARCH_LOG("[LED]: rpi LED driver free\n");
}

static int set_gpio(int gpio,int value)
{
    FILE *fp;
    char buf[256];
    sprintf(buf,"/sys/class/gpio/%d/value",gpio);
    fp = fopen(buf,"w");
    if(fp == NULL)
    {
        RARCH_WARN("[LED]: failed to set GPIO %d\n",gpio);
        return -1;
    }
    fprintf(fp,"%d\n",value?1:0);
    fclose(fp);
    return 1;
}


static int setup_gpio(int gpio) {
    FILE *fp;
    char buf[256];
    sprintf(buf,"/sys/class/gpio/%d/direction",gpio);
    fp = fopen(buf,"w");
    if(fp == NULL) {
        sprintf(buf,"/sys/class/gpio/export");
        fp = fopen(buf,"w");
        if(fp == NULL)
        {
            RARCH_WARN("[LED]: failed to export GPIO %d\n",gpio);
            return -1;
        }
        fprintf(fp,"%d\n",gpio);
        fclose(fp);

        sprintf(buf,"/sys/class/gpio/%d/direction",gpio);
        fp = fopen(buf,"w");    
    }
    if(fp == NULL)
    {
        RARCH_WARN("[LED]: failed to set direction GPIO %d\n",gpio);
        return -1;
    }
    fprintf(fp,"out\n");
    fclose(fp);
    return 1;
    
}
static void rpi_set(int led,int state)
{
    int gpio = 0;
    if((led < 0) || (led >= MAX_LEDS))
    {
        RARCH_WARN("[LED]: invalid led %d\n",led);
        return;
    }
    gpio = cur->map[led];
    if(gpio <= 0) return;

    if(cur->setup[led]==0)
    {
        RARCH_LOG("[LED]: rpi setup led %d gpio %d\n",led,gpio,state);
        cur->setup[led] = setup_gpio(gpio);
        if(cur->setup[led] <= 0)
        {
            RARCH_WARN("[LED]: failed to setup led %d gpio %d\n",led,gpio);
        }
    }
    if(cur->setup[led] > 0)
    {
        RARCH_LOG("[LED]: rpi LED driver set led %d gpio %d = %d\n",led,gpio,state);
        set_gpio(gpio,state);
    }
}

static led_driver_t rpi_led_driver_ins = { rpi_init, rpi_free, rpi_set };
led_driver_t *rpi_led_driver = &rpi_led_driver_ins;