led.cpp

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 * modification, are permitted provided that the following conditions
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/**
 * @file led.cpp
 *
 * LED driver.
 */

#include <px4_platform_common/px4_config.h>
#include <drivers/drv_board_led.h>
#include <stdio.h>

#include "VirtDevObj.hpp"

using namespace DriverFramework;

/*
 * Ideally we'd be able to get these from up_internal.h,
 * but since we want to be able to disable the NuttX use
 * of leds for system indication at will and there is no
 * separate switch, we need to build independent of the
 * CONFIG_ARCH_LEDS configuration switch.
 */
__BEGIN_DECLS
extern void led_init();
extern void led_on(int led);
extern void led_off(int led);
extern void led_toggle(int led);
__END_DECLS

class LED : public VirtDevObj
{
public:
    LED();
    ~LED() override = default;

    int init() override;
    int devIOCTL(unsigned long cmd, unsigned long arg) override;

protected:
    void    _measure() override {}
};

LED::LED() :
    VirtDevObj("led", "/dev/ledsim", LED_BASE_DEVICE_PATH, 0)
{
    // force immediate init/device registration
    init();
}

int
LED::init()
{
    int ret = VirtDevObj::init();

    if (ret == 0) {
        led_init();
    }

    return ret;
}

int
LED::devIOCTL(unsigned long cmd, unsigned long arg)
{
    int result = OK;

    switch (cmd) {
    case LED_ON:
        led_on(arg);
        break;

    case LED_OFF:
        led_off(arg);
        break;

    case LED_TOGGLE:
        led_toggle(arg);
        break;


    default:
        result = VirtDevObj::devIOCTL(cmd, arg);
    }

    return result;
}

namespace
{
LED *gLED;
}

void
drv_led_start(void)
{
    if (gLED == nullptr) {
        gLED = new LED;

        if (gLED != nullptr) {
            gLED->init();
        }
    }
}