leds-88pm860x.c

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/*
 * LED driver for Marvell 88PM860x
 *
 * Copyright (C) 2009 Marvell International Ltd.
 *  Haojian Zhuang <[email protected]>
 *
 * 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/kernel.h>
#include <linux/init.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/i2c.h>
#include <linux/leds.h>
#include <linux/slab.h>
#include <linux/workqueue.h>
#include <linux/mfd/88pm860x.h>
#include <linux/module.h>

#define LED_PWM_MASK        (0x1F)
#define LED_CURRENT_MASK    (0x07 << 5)

#define LED_BLINK_MASK      (0x7F)

#define LED_ON_CONTINUOUS   (0x0F << 3)

#define LED1_BLINK_EN       (1 << 1)
#define LED2_BLINK_EN       (1 << 2)

struct pm860x_led {
    struct led_classdev cdev;
    struct i2c_client *i2c;
    struct work_struct work;
    struct pm860x_chip *chip;
    struct mutex lock;
    char name[MFD_NAME_SIZE];

    int port;
    int iset;
    unsigned char brightness;
    unsigned char current_brightness;

    int reg_control;
    int reg_blink;
    int blink_mask;
};

static int led_power_set(struct pm860x_chip *chip, int port, int on)
{
    int ret = -EINVAL;

    switch (port) {
    case 0:
    case 1:
    case 2:
        ret = on ? pm8606_osc_enable(chip, RGB1_ENABLE) :
            pm8606_osc_disable(chip, RGB1_ENABLE);
        break;
    case 3:
    case 4:
    case 5:
        ret = on ? pm8606_osc_enable(chip, RGB2_ENABLE) :
            pm8606_osc_disable(chip, RGB2_ENABLE);
        break;
    }
    return ret;
}

static void pm860x_led_work(struct work_struct *work)
{

    struct pm860x_led *led;
    struct pm860x_chip *chip;
    unsigned char buf[3];
    int ret;

    led = container_of(work, struct pm860x_led, work);
    chip = led->chip;
    mutex_lock(&led->lock);
    if ((led->current_brightness == 0) && led->brightness) {
        led_power_set(chip, led->port, 1);
        if (led->iset) {
            pm860x_set_bits(led->i2c, led->reg_control,
                    LED_CURRENT_MASK, led->iset);
        }
        pm860x_set_bits(led->i2c, led->reg_blink,
                LED_BLINK_MASK, LED_ON_CONTINUOUS);
        pm860x_set_bits(led->i2c, PM8606_WLED3B, led->blink_mask,
                led->blink_mask);
    }
    pm860x_set_bits(led->i2c, led->reg_control, LED_PWM_MASK,
            led->brightness);

    if (led->brightness == 0) {
        pm860x_bulk_read(led->i2c, led->reg_control, 3, buf);
        ret = buf[0] & LED_PWM_MASK;
        ret |= buf[1] & LED_PWM_MASK;
        ret |= buf[2] & LED_PWM_MASK;
        if (ret == 0) {
            /* unset current since no led is lighting */
            pm860x_set_bits(led->i2c, led->reg_control,
                    LED_CURRENT_MASK, 0);
            pm860x_set_bits(led->i2c, PM8606_WLED3B,
                    led->blink_mask, 0);
            led_power_set(chip, led->port, 0);
        }
    }
    led->current_brightness = led->brightness;
    dev_dbg(chip->dev, "Update LED. (reg:%d, brightness:%d)\n",
        led->reg_control, led->brightness);
    mutex_unlock(&led->lock);
}

static void pm860x_led_set(struct led_classdev *cdev,
               enum led_brightness value)
{
    struct pm860x_led *data = container_of(cdev, struct pm860x_led, cdev);

    data->brightness = value >> 3;
    schedule_work(&data->work);
}

#ifdef CONFIG_OF
static int pm860x_led_dt_init(struct platform_device *pdev,
                  struct pm860x_led *data)
{
    struct device_node *nproot = pdev->dev.parent->of_node, *np;
    int iset = 0;
    if (!nproot)
        return -ENODEV;
    nproot = of_find_node_by_name(nproot, "leds");
    if (!nproot) {
        dev_err(&pdev->dev, "failed to find leds node\n");
        return -ENODEV;
    }
    for_each_child_of_node(nproot, np) {
        if (!of_node_cmp(np->name, data->name)) {
            of_property_read_u32(np, "marvell,88pm860x-iset",
                         &iset);
            data->iset = PM8606_LED_CURRENT(iset);
            break;
        }
    }
    return 0;
}
#else
#define pm860x_led_dt_init(x, y)    (-1)
#endif

static int pm860x_led_probe(struct platform_device *pdev)
{
    struct pm860x_chip *chip = dev_get_drvdata(pdev->dev.parent);
    struct pm860x_led_pdata *pdata = pdev->dev.platform_data;
    struct pm860x_led *data;
    struct resource *res;
    int ret = 0;

    data = devm_kzalloc(&pdev->dev, sizeof(struct pm860x_led), GFP_KERNEL);
    if (data == NULL)
        return -ENOMEM;
    res = platform_get_resource_byname(pdev, IORESOURCE_REG, "control");
    if (!res) {
        dev_err(&pdev->dev, "No REG resource for control\n");
        ret = -ENXIO;
        goto out;
    }
    data->reg_control = res->start;
    res = platform_get_resource_byname(pdev, IORESOURCE_REG, "blink");
    if (!res) {
        dev_err(&pdev->dev, "No REG resource for blink\n");
        ret = -ENXIO;
        goto out;
    }
    data->reg_blink = res->start;
    memset(data->name, 0, MFD_NAME_SIZE);
    switch (pdev->id) {
    case 0:
        data->blink_mask = LED1_BLINK_EN;
        sprintf(data->name, "led0-red");
        break;
    case 1:
        data->blink_mask = LED1_BLINK_EN;
        sprintf(data->name, "led0-green");
        break;
    case 2:
        data->blink_mask = LED1_BLINK_EN;
        sprintf(data->name, "led0-blue");
        break;
    case 3:
        data->blink_mask = LED2_BLINK_EN;
        sprintf(data->name, "led1-red");
        break;
    case 4:
        data->blink_mask = LED2_BLINK_EN;
        sprintf(data->name, "led1-green");
        break;
    case 5:
        data->blink_mask = LED2_BLINK_EN;
        sprintf(data->name, "led1-blue");
        break;
    }
    dev_set_drvdata(&pdev->dev, data);
    data->chip = chip;
    data->i2c = (chip->id == CHIP_PM8606) ? chip->client : chip->companion;
    data->port = pdev->id;
    if (pm860x_led_dt_init(pdev, data))
        if (pdata)
            data->iset = pdata->iset;

    data->current_brightness = 0;
    data->cdev.name = data->name;
    data->cdev.brightness_set = pm860x_led_set;
    mutex_init(&data->lock);
    INIT_WORK(&data->work, pm860x_led_work);

    ret = led_classdev_register(chip->dev, &data->cdev);
    if (ret < 0) {
        dev_err(&pdev->dev, "Failed to register LED: %d\n", ret);
        return ret;
    }
    pm860x_led_set(&data->cdev, 0);
    return 0;
out:
    devm_kfree(&pdev->dev, data);
    return ret;
}

static int pm860x_led_remove(struct platform_device *pdev)
{
    struct pm860x_led *data = platform_get_drvdata(pdev);

    led_classdev_unregister(&data->cdev);

    return 0;
}

static struct platform_driver pm860x_led_driver = {
    .driver = {
        .name   = "88pm860x-led",
        .owner  = THIS_MODULE,
    },
    .probe  = pm860x_led_probe,
    .remove = pm860x_led_remove,
};

module_platform_driver(pm860x_led_driver);

MODULE_DESCRIPTION("LED driver for Marvell PM860x");
MODULE_AUTHOR("Haojian Zhuang <[email protected]>");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:88pm860x-led");