linux-imx

/*

 * leds-regulator.c - LED class driver for regulator driven LEDs.

 *

 * Copyright (C) 2009 Antonio Ospite <ospite@studenti.unina.it>

 *

 * Inspired by leds-wm8350 driver.

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License version 2 as

 * published by the Free Software Foundation.

 *

 */

​

#include <linux/module.h>

#include <linux/err.h>

#include <linux/slab.h>

#include <linux/leds.h>

#include <linux/leds-regulator.h>

#include <linux/platform_device.h>

#include <linux/regulator/consumer.h>

​

#define to_regulator_led(led_cdev) \

    container_of(led_cdev, struct regulator_led, cdev)

​

struct regulator_led {

    struct led_classdev cdev;

    int enabled;

    struct mutex mutex;

​

    struct regulator *vcc;

};

​

static inline int led_regulator_get_max_brightness(struct regulator *supply)

{

    int ret;

    int voltage = regulator_list_voltage(supply, 0);

​

    if (voltage <= 0)

        return 1;

​

    /* even if regulator can't change voltages,

     * we still assume it can change status

     * and the LED can be turned on and off.

     */

    ret = regulator_set_voltage(supply, voltage, voltage);

    if (ret < 0)

        return 1;

​

    return regulator_count_voltages(supply);

}

​

static int led_regulator_get_voltage(struct regulator *supply,

        enum led_brightness brightness)

{

    if (brightness == 0)

        return -EINVAL;

​

    return regulator_list_voltage(supply, brightness - 1);

}

​

​

static void regulator_led_enable(struct regulator_led *led)

{