/*********************************************************************************
 *      Copyright:  (C) 2019 LingYun IoT System Studio
 *                  All rights reserved.
 *
 *       Filename:  gpio.c
 *    Description:  This file is GPIO input/output functions
 *                 
 *        Version:  1.0.0(2019年06月24日)
 *         Author:  Guo Wenxue <guowenxue@gmail.com>
 *      ChangeLog:  1, Release initial version on "2019年06月24日 23时46分47秒"
 *                 
 ********************************************************************************/

#include "lylib/logger.h"
#include "gpio.h"

#define RPI_GPIONAME        "gpiochip0"

static struct gpiod_chip    *s_chip;
static gpio_t               *s_gpio = NULL;

int gpio_init(gpio_t *gpio)
{
    int                 i;
    gpio_info_t        *gpioinfo;


    s_gpio = gpio;


    if( !gpio )
    {
        log_err("Invalid input arguments $gpio\n");
        return -1;
    }


    if( !gpio->incnt && !gpio->outcnt )
    {
        log_warn("WARNNING: No GPIO pins configured\n");
        return 0;
    }


    /*  gpiod open chip */
    s_chip = gpiod_chip_open_by_name(RPI_GPIONAME);
    if( !s_chip )
    {
        log_err("gpiod open chip failure, maybe you need running as root\n");
        return -2;
    }
    log_nrml("gpiod initialise open chip ok\n");


    /*  gpiod request all output pins */
    for(i=0; i<gpio->outcnt; i++)
    {
        gpio->output[i].line = gpiod_chip_get_line(s_chip, gpio->output[i].pin);
        if( !gpio->output[i].line )
        {
            log_err("gpiod get line for '%s' pin[#%d] failure\n", gpio->output[i].name, gpio->output[i].pin );
            return -2;
        }

        gpiod_line_request_output(gpio->output[i].line, gpio->output[i].name, !gpio->output[i].active_level);
        log_nrml("gpiod request '%s' pin[#%d] output ok\n", gpio->output[i].name, gpio->output[i].pin);
    }


    /*  gpiod request all input pins */
    for(i=0; i<gpio->incnt; i++)
    {
        gpio->input[i].line = gpiod_chip_get_line(s_chip, gpio->input[i].pin);
        if( !gpio->input[i].line )
        {
            log_err("gpiod get line for '%s' pin[#%d] failure\n", gpio->input[i].name, gpio->input[i].pin );
            return -2;
        }

        if( gpio->output[i].active_level )
        {
            gpiod_line_request_rising_edge_events(gpio->input[i].line, gpio->input[i].name);
            log_nrml("gpiod request '%s' pin[#%d] for rising edge event ok\n", gpio->input[i].name, gpio->input[i].pin);
        }
        else
        {
            gpiod_line_request_falling_edge_events(gpio->input[i].line, gpio->input[i].name);
            log_nrml("gpiod request '%s' pin[#%d] for falling edge event ok\n", gpio->input[i].name, gpio->input[i].pin);
        }
    }
}


void gpio_term(void)
{
    int              i;

    log_nrml("start teriminated GPIO\n");

    if( !s_gpio->incnt && !s_gpio->outcnt )
    {
        return ;
    }


    for(i=0; i<s_gpio->outcnt; i++)
    {
        gpiod_line_release(s_gpio->output[i].line);
    }


    for(i=0; i<s_gpio->incnt; i++)
    {
        gpiod_line_release(s_gpio->input[i].line);
    }

    gpiod_chip_close(s_chip);
}

void gpio_out(char *name, int cmd)
{
    int              i;
    int              found = 0;

    for( i=0; i<s_gpio->outcnt; i++ )
    {
        if( !strncasecmp(s_gpio->output[i].name, name, strlen(name)))
        {
            found = 1;
            break;
        }
    }

    if( !found )
    {
        log_err("GPIO output for '%s' pin not found\n", name);
        return ;
    }

    if( OFF == cmd )
    {
        gpiod_line_set_value(s_gpio->output[i].line, s_gpio->output[i].active_level);
    }
    else
    {
        gpiod_line_set_value(s_gpio->output[i].line, !s_gpio->output[i].active_level);
    }

    return ;
}


#if 0
/* Return value: 1(HIGH): Sombody detected  0(LOW): Nobody detected */
int infrared_detect(void)
{
    struct gpiod_line_event  event;

    /* This function will block, must call it to setup */
    if( gpiod_line_event_wait(s_infrared_lines, NULL) < 0 )
    {
        //log_err("infrared gpiod line wait event failure!\n");
        return 0;
    }

    /* This function will block, must read to clear the event  */
    if (gpiod_line_event_read(s_infrared_lines, &event) < 0)
    {
        log_err("gpiod line event read failure!\n");
        return 0;
    }

    if (event.event_type == GPIOD_LINE_EVENT_RISING_EDGE)
        return 1;
    else
        return 0;
}

#endif