/*

 *  LCD / Backlight control code for Sharp SL-6000x (tosa)

 *

 *  Copyright (c) 2005		Dirk Opfer

 *  Copyright (c) 2007,2008	Dmitry Baryshkov

 *

 *  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/module.h>

#include <linux/device.h>

#include <linux/spi/spi.h>

#include <linux/i2c.h>

#include <linux/gpio.h>

#include <linux/fb.h>

#include <linux/backlight.h>

#include <asm/mach/sharpsl_param.h>

#include <mach/tosa.h>

#define COMADJ_DEFAULT	97

#define DAC_CH1		0

#define DAC_CH2		1

struct tosa_bl_data {

	struct i2c_client *i2c;

	struct backlight_device *bl;

	int comadj;

};

static void tosa_bl_set_backlight(struct tosa_bl_data *data, int brightness)

{

	struct spi_device *spi = data->i2c->dev.platform_data;

	i2c_smbus_write_byte_data(data->i2c, DAC_CH1, data->comadj);

	/* SetBacklightDuty */

	i2c_smbus_write_byte_data(data->i2c, DAC_CH2, (u8)(brightness & 0xff));

	/* SetBacklightVR */

	gpio_set_value(TOSA_GPIO_BL_C20MA, brightness & 0x100);

	tosa_bl_enable(spi, brightness);

}

static int tosa_bl_update_status(struct backlight_device *dev)

{

	struct backlight_properties *props = &dev->props;

	struct tosa_bl_data *data = dev_get_drvdata(&dev->dev);

	int power = max(props->power, props->fb_blank);

	int brightness = props->brightness;

	if (power)

		brightness = 0;

	tosa_bl_set_backlight(data, brightness);

	return 0;

}

static int tosa_bl_get_brightness(struct backlight_device *dev)

{

	struct backlight_properties *props = &dev->props;

	return props->brightness;

}

static struct backlight_ops bl_ops = {

	.get_brightness		= tosa_bl_get_brightness,

	.update_status		= tosa_bl_update_status,

};

static int __devinit tosa_bl_probe(struct i2c_client *client,

		const struct i2c_device_id *id)

{

	struct tosa_bl_data *data = kzalloc(sizeof(struct tosa_bl_data), GFP_KERNEL);

	int ret = 0;

	if (!data)

		return -ENOMEM;

	data->comadj = sharpsl_param.comadj == -1 ? COMADJ_DEFAULT : sharpsl_param.comadj;

	ret = gpio_request(TOSA_GPIO_BL_C20MA, "backlight");

	if (ret) {

		dev_dbg(&data->bl->dev, "Unable to request gpio!\n");

		goto err_gpio_bl;

	}

	ret = gpio_direction_output(TOSA_GPIO_BL_C20MA, 0);

	if (ret)

		goto err_gpio_dir;

	i2c_set_clientdata(client, data);

	data->i2c = client;

	data->bl = backlight_device_register("tosa-bl", &client->dev,

			data, &bl_ops);

	if (IS_ERR(data->bl)) {

		ret = PTR_ERR(data->bl);

		goto err_reg;

	}

	data->bl->props.brightness = 69;

	data->bl->props.max_brightness = 512 - 1;

	data->bl->props.power = FB_BLANK_UNBLANK;

	backlight_update_status(data->bl);

	return 0;

err_reg:

	data->bl = NULL;

	i2c_set_clientdata(client, NULL);

err_gpio_dir:

	gpio_free(TOSA_GPIO_BL_C20MA);

err_gpio_bl:

	kfree(data);

	return ret;

}

static int __devexit tosa_bl_remove(struct i2c_client *client)

{

	struct tosa_bl_data *data = i2c_get_clientdata(client);

	backlight_device_unregister(data->bl);

	data->bl = NULL;

	i2c_set_clientdata(client, NULL);

	gpio_free(TOSA_GPIO_BL_C20MA);

	kfree(data);

	return 0;

}

#ifdef CONFIG_PM

static int tosa_bl_suspend(struct i2c_client *client, pm_message_t pm)

{

	struct tosa_bl_data *data = i2c_get_clientdata(client);

	tosa_bl_set_backlight(data, 0);

	return 0;

}

static int tosa_bl_resume(struct i2c_client *client)

{

	struct tosa_bl_data *data = i2c_get_clientdata(client);

	backlight_update_status(data->bl);

	return 0;

}

#else

#define tosa_bl_suspend NULL

#define tosa_bl_resume NULL

#endif

static const struct i2c_device_id tosa_bl_id[] = {

	{ "tosa-bl", 0 },

	{ },

};

static struct i2c_driver tosa_bl_driver = {

	.driver = {

		.name		= "tosa-bl",

		.owner		= THIS_MODULE,

	},

	.probe		= tosa_bl_probe,

	.remove		= __devexit_p(tosa_bl_remove),

	.suspend	= tosa_bl_suspend,

	.resume		= tosa_bl_resume,

	.id_table	= tosa_bl_id,

};

static int __init tosa_bl_init(void)

{

	return i2c_add_driver(&tosa_bl_driver);

}

static void __exit tosa_bl_exit(void)

{

	i2c_del_driver(&tosa_bl_driver);

}

module_init(tosa_bl_init);

module_exit(tosa_bl_exit);

MODULE_AUTHOR("Dmitry Baryshkov");

MODULE_LICENSE("GPL v2");

MODULE_DESCRIPTION("LCD/Backlight control for Sharp SL-6000 PDA");