linux-imx

/*

 * LP5521/LP5523/LP55231/LP5562 Common Driver

 *

 * Copyright 2012 Texas Instruments

 *

 * Author: Milo(Woogyom) Kim <milo.kim@ti.com>

 *

 * 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.

 *

 * Derived from leds-lp5521.c, leds-lp5523.c

 */

​

#include <linux/clk.h>

#include <linux/delay.h>

#include <linux/firmware.h>

#include <linux/i2c.h>

#include <linux/leds.h>

#include <linux/module.h>

#include <linux/platform_data/leds-lp55xx.h>

#include <linux/slab.h>

#include <linux/gpio.h>

#include <linux/of_gpio.h>

​

#include "leds-lp55xx-common.h"

​

/* External clock rate */

#define LP55XX_CLK_32K          32768

​

static struct lp55xx_led *cdev_to_lp55xx_led(struct led_classdev *cdev)

{

    return container_of(cdev, struct lp55xx_led, cdev);

}

​

static struct lp55xx_led *dev_to_lp55xx_led(struct device *dev)

{

    return cdev_to_lp55xx_led(dev_get_drvdata(dev));

}

​

static void lp55xx_reset_device(struct lp55xx_chip *chip)

{

    struct lp55xx_device_config *cfg = chip->cfg;

    u8 addr = cfg->reset.addr;

    u8 val  = cfg->reset.val;

​

    /* no error checking here because no ACK from the device after reset */

    lp55xx_write(chip, addr, val);

}

​

static int lp55xx_detect_device(struct lp55xx_chip *chip)

{

    struct lp55xx_device_config *cfg = chip->cfg;

    u8 addr = cfg->enable.addr;

    u8 val  = cfg->enable.val;

    int ret;

​

    ret = lp55xx_write(chip, addr, val);

    if (ret)

        return ret;

​

    usleep_range(1000, 2000);

​

    ret = lp55xx_read(chip, addr, &val);

    if (ret)

        return ret;

​

    if (val != cfg->enable.val)

        return -ENODEV;

​

    return 0;

}

​

static int lp55xx_post_init_device(struct lp55xx_chip *chip)

{

    struct lp55xx_device_config *cfg = chip->cfg;

​

    if (!cfg->post_init_device)

        return 0;

​

    return cfg->post_init_device(chip);

}

​

static ssize_t lp55xx_show_current(struct device *dev,

                struct device_attribute *attr,

                char *buf)

{

    struct lp55xx_led *led = dev_to_lp55xx_led(dev);

​

    return scnprintf(buf, PAGE_SIZE, "%d\n", led->led_current);

}

​