/*
   * leds-max8997.c - LED class driver for MAX8997 LEDs.
   *
   * Copyright (C) 2011 Samsung Electronics
   * Donggeun Kim <dg77.kim@samsung.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.
   *
   */
  
  #include <linux/module.h>
  #include <linux/err.h>
  #include <linux/slab.h>
  #include <linux/workqueue.h>
  #include <linux/leds.h>
  #include <linux/mfd/max8997.h>
  #include <linux/mfd/max8997-private.h>
  #include <linux/platform_device.h>
  
  #define MAX8997_LED_FLASH_SHIFT			3
  #define MAX8997_LED_FLASH_CUR_MASK		0xf8
  #define MAX8997_LED_MOVIE_SHIFT			4
  #define MAX8997_LED_MOVIE_CUR_MASK		0xf0
  
  #define MAX8997_LED_FLASH_MAX_BRIGHTNESS	0x1f
  #define MAX8997_LED_MOVIE_MAX_BRIGHTNESS	0xf
  #define MAX8997_LED_NONE_MAX_BRIGHTNESS		0
  
  #define MAX8997_LED0_FLASH_MASK			0x1
  #define MAX8997_LED0_FLASH_PIN_MASK		0x5
  #define MAX8997_LED0_MOVIE_MASK			0x8
  #define MAX8997_LED0_MOVIE_PIN_MASK		0x28
  
  #define MAX8997_LED1_FLASH_MASK			0x2
  #define MAX8997_LED1_FLASH_PIN_MASK		0x6
  #define MAX8997_LED1_MOVIE_MASK			0x10
  #define MAX8997_LED1_MOVIE_PIN_MASK		0x30
  
  #define MAX8997_LED_BOOST_ENABLE_MASK		(1 << 6)
  
  struct max8997_led {
  	struct max8997_dev *iodev;
  	struct led_classdev cdev;
  	bool enabled;
  	int id;
  	enum max8997_led_mode led_mode;
  	struct mutex mutex;
  };
  
  static void max8997_led_set_mode(struct max8997_led *led,
  			enum max8997_led_mode mode)
  {
  	int ret;
  	struct i2c_client *client = led->iodev->i2c;
  	u8 mask = 0, val;
  
  	switch (mode) {
  	case MAX8997_FLASH_MODE:
  		mask = MAX8997_LED1_FLASH_MASK | MAX8997_LED0_FLASH_MASK;
  		val = led->id ?
  		      MAX8997_LED1_FLASH_MASK : MAX8997_LED0_FLASH_MASK;
  		led->cdev.max_brightness = MAX8997_LED_FLASH_MAX_BRIGHTNESS;
  		break;
  	case MAX8997_MOVIE_MODE:
  		mask = MAX8997_LED1_MOVIE_MASK | MAX8997_LED0_MOVIE_MASK;
  		val = led->id ?
  		      MAX8997_LED1_MOVIE_MASK : MAX8997_LED0_MOVIE_MASK;
  		led->cdev.max_brightness = MAX8997_LED_MOVIE_MAX_BRIGHTNESS;
  		break;
  	case MAX8997_FLASH_PIN_CONTROL_MODE:
  		mask = MAX8997_LED1_FLASH_PIN_MASK |
  		       MAX8997_LED0_FLASH_PIN_MASK;
  		val = led->id ?
  		      MAX8997_LED1_FLASH_PIN_MASK : MAX8997_LED0_FLASH_PIN_MASK;
  		led->cdev.max_brightness = MAX8997_LED_FLASH_MAX_BRIGHTNESS;
  		break;
  	case MAX8997_MOVIE_PIN_CONTROL_MODE:
  		mask = MAX8997_LED1_MOVIE_PIN_MASK |
  		       MAX8997_LED0_MOVIE_PIN_MASK;
  		val = led->id ?
  		      MAX8997_LED1_MOVIE_PIN_MASK : MAX8997_LED0_MOVIE_PIN_MASK;
  		led->cdev.max_brightness = MAX8997_LED_MOVIE_MAX_BRIGHTNESS;
  		break;
  	default:
  		led->cdev.max_brightness = MAX8997_LED_NONE_MAX_BRIGHTNESS;
  		break;
  	}
  
  	if (mask) {
  		ret = max8997_update_reg(client, MAX8997_REG_LEN_CNTL, val,
  					 mask);
  		if (ret)
  			dev_err(led->iodev->dev,
  				"failed to update register(%d)
  ", ret);
  	}
  
  	led->led_mode = mode;
  }
  
  static void max8997_led_enable(struct max8997_led *led, bool enable)
  {
  	int ret;
  	struct i2c_client *client = led->iodev->i2c;
  	u8 val = 0, mask = MAX8997_LED_BOOST_ENABLE_MASK;
  
  	if (led->enabled == enable)
  		return;
  
  	val = enable ? MAX8997_LED_BOOST_ENABLE_MASK : 0;
  
  	ret = max8997_update_reg(client, MAX8997_REG_BOOST_CNTL, val, mask);
  	if (ret)
  		dev_err(led->iodev->dev,
  			"failed to update register(%d)
  ", ret);
  
  	led->enabled = enable;
  }
  
  static void max8997_led_set_current(struct max8997_led *led,
  				enum led_brightness value)
  {
  	int ret;
  	struct i2c_client *client = led->iodev->i2c;
  	u8 val = 0, mask = 0, reg = 0;
  
  	switch (led->led_mode) {
  	case MAX8997_FLASH_MODE:
  	case MAX8997_FLASH_PIN_CONTROL_MODE:
  		val = value << MAX8997_LED_FLASH_SHIFT;
  		mask = MAX8997_LED_FLASH_CUR_MASK;
  		reg = led->id ? MAX8997_REG_FLASH2_CUR : MAX8997_REG_FLASH1_CUR;
  		break;
  	case MAX8997_MOVIE_MODE:
  	case MAX8997_MOVIE_PIN_CONTROL_MODE:
  		val = value << MAX8997_LED_MOVIE_SHIFT;
  		mask = MAX8997_LED_MOVIE_CUR_MASK;
  		reg = MAX8997_REG_MOVIE_CUR;
  		break;
  	default:
  		break;
  	}
  
  	if (mask) {
  		ret = max8997_update_reg(client, reg, val, mask);
  		if (ret)
  			dev_err(led->iodev->dev,
  				"failed to update register(%d)
  ", ret);
  	}
  }
  
  static void max8997_led_brightness_set(struct led_classdev *led_cdev,
  				enum led_brightness value)
  {
  	struct max8997_led *led =
  			container_of(led_cdev, struct max8997_led, cdev);
  
  	if (value) {
  		max8997_led_set_current(led, value);
  		max8997_led_enable(led, true);
  	} else {
  		max8997_led_set_current(led, value);
  		max8997_led_enable(led, false);
  	}
  }
  
  static ssize_t max8997_led_show_mode(struct device *dev,
  				struct device_attribute *attr, char *buf)
  {
  	struct led_classdev *led_cdev = dev_get_drvdata(dev);
  	struct max8997_led *led =
  			container_of(led_cdev, struct max8997_led, cdev);
  	ssize_t ret = 0;
  
  	mutex_lock(&led->mutex);
  
  	switch (led->led_mode) {
  	case MAX8997_FLASH_MODE:
  		ret += sprintf(buf, "FLASH
  ");
  		break;
  	case MAX8997_MOVIE_MODE:
  		ret += sprintf(buf, "MOVIE
  ");
  		break;
  	case MAX8997_FLASH_PIN_CONTROL_MODE:
  		ret += sprintf(buf, "FLASH_PIN_CONTROL
  ");
  		break;
  	case MAX8997_MOVIE_PIN_CONTROL_MODE:
  		ret += sprintf(buf, "MOVIE_PIN_CONTROL
  ");
  		break;
  	default:
  		ret += sprintf(buf, "NONE
  ");
  		break;
  	}
  
  	mutex_unlock(&led->mutex);
  
  	return ret;
  }
  
  static ssize_t max8997_led_store_mode(struct device *dev,
  				struct device_attribute *attr,
  				const char *buf, size_t size)
  {
  	struct led_classdev *led_cdev = dev_get_drvdata(dev);
  	struct max8997_led *led =
  			container_of(led_cdev, struct max8997_led, cdev);
  	enum max8997_led_mode mode;
  
  	mutex_lock(&led->mutex);
  
  	if (!strncmp(buf, "FLASH_PIN_CONTROL", 17))
  		mode = MAX8997_FLASH_PIN_CONTROL_MODE;
  	else if (!strncmp(buf, "MOVIE_PIN_CONTROL", 17))
  		mode = MAX8997_MOVIE_PIN_CONTROL_MODE;
  	else if (!strncmp(buf, "FLASH", 5))
  		mode = MAX8997_FLASH_MODE;
  	else if (!strncmp(buf, "MOVIE", 5))
  		mode = MAX8997_MOVIE_MODE;
  	else
  		mode = MAX8997_NONE;
  
  	max8997_led_set_mode(led, mode);
  
  	mutex_unlock(&led->mutex);
  
  	return size;
  }
  
  static DEVICE_ATTR(mode, 0644, max8997_led_show_mode, max8997_led_store_mode);
  
  static struct attribute *max8997_attrs[] = {
  	&dev_attr_mode.attr,
  	NULL
  };
  ATTRIBUTE_GROUPS(max8997);
  
  static int max8997_led_probe(struct platform_device *pdev)
  {
  	struct max8997_dev *iodev = dev_get_drvdata(pdev->dev.parent);
  	struct max8997_platform_data *pdata = dev_get_platdata(iodev->dev);
  	struct max8997_led *led;
  	char name[20];
  	int ret = 0;
  
  	if (pdata == NULL) {
  		dev_err(&pdev->dev, "no platform data
  ");
  		return -ENODEV;
  	}
  
  	led = devm_kzalloc(&pdev->dev, sizeof(*led), GFP_KERNEL);
  	if (led == NULL)
  		return -ENOMEM;
  
  	led->id = pdev->id;
  	snprintf(name, sizeof(name), "max8997-led%d", pdev->id);
  
  	led->cdev.name = name;
  	led->cdev.brightness_set = max8997_led_brightness_set;
  	led->cdev.flags |= LED_CORE_SUSPENDRESUME;
  	led->cdev.brightness = 0;
  	led->cdev.groups = max8997_groups;
  	led->iodev = iodev;
  
  	/* initialize mode and brightness according to platform_data */
  	if (pdata->led_pdata) {
  		u8 mode = 0, brightness = 0;
  
  		mode = pdata->led_pdata->mode[led->id];
  		brightness = pdata->led_pdata->brightness[led->id];
  
  		max8997_led_set_mode(led, pdata->led_pdata->mode[led->id]);
  
  		if (brightness > led->cdev.max_brightness)
  			brightness = led->cdev.max_brightness;
  		max8997_led_set_current(led, brightness);
  		led->cdev.brightness = brightness;
  	} else {
  		max8997_led_set_mode(led, MAX8997_NONE);
  		max8997_led_set_current(led, 0);
  	}
  
  	mutex_init(&led->mutex);
  
  	platform_set_drvdata(pdev, led);
  
  	ret = led_classdev_register(&pdev->dev, &led->cdev);
  	if (ret < 0)
  		return ret;
  
  	return 0;
  }
  
  static int max8997_led_remove(struct platform_device *pdev)
  {
  	struct max8997_led *led = platform_get_drvdata(pdev);
  
  	led_classdev_unregister(&led->cdev);
  
  	return 0;
  }
  
  static struct platform_driver max8997_led_driver = {
  	.driver = {
  		.name  = "max8997-led",
  	},
  	.probe  = max8997_led_probe,
  	.remove = max8997_led_remove,
  };
  
  module_platform_driver(max8997_led_driver);
  
  MODULE_AUTHOR("Donggeun Kim <dg77.kim@samsung.com>");
  MODULE_DESCRIPTION("MAX8997 LED driver");
  MODULE_LICENSE("GPL");
  MODULE_ALIAS("platform:max8997-led");