/*

 *  Backlight Driver for HP Jornada 680

 *

 *  Copyright (c) 2005 Andriy Skulysh

 *

 *  Based on Sharp's Corgi Backlight Driver

 *

 * This file is subject to the terms and conditions of the GNU General Public

 * License.  See the file "COPYING" in the main directory of this archive

 * for more details.

 */

#include <linux/module.h>

#include <linux/kernel.h>

#include <linux/init.h>

#include <linux/platform_device.h>

#include <linux/spinlock.h>

#include <linux/fb.h>

#include <linux/backlight.h>

#include <cpu/dac.h>

#include <mach/hp6xx.h>

#include <asm/hd64461.h>

#define HP680_MAX_INTENSITY 255

#define HP680_DEFAULT_INTENSITY 10

static int hp680bl_suspended;

static int current_intensity = 0;

static DEFINE_SPINLOCK(bl_lock);

static void hp680bl_send_intensity(struct backlight_device *bd)

{

	unsigned long flags;

	u16 v;

	int intensity = bd->props.brightness;

	if (bd->props.power != FB_BLANK_UNBLANK)

		intensity = 0;

	if (bd->props.fb_blank != FB_BLANK_UNBLANK)

		intensity = 0;

	if (hp680bl_suspended)

		intensity = 0;

	spin_lock_irqsave(&bl_lock, flags);

	if (intensity && current_intensity == 0) {

		sh_dac_enable(DAC_LCD_BRIGHTNESS);

		v = inw(HD64461_GPBDR);

		v &= ~HD64461_GPBDR_LCDOFF;

		outw(v, HD64461_GPBDR);

		sh_dac_output(255-(u8)intensity, DAC_LCD_BRIGHTNESS);

	} else if (intensity == 0 && current_intensity != 0) {

		sh_dac_output(255-(u8)intensity, DAC_LCD_BRIGHTNESS);

		sh_dac_disable(DAC_LCD_BRIGHTNESS);

		v = inw(HD64461_GPBDR);

		v |= HD64461_GPBDR_LCDOFF;

		outw(v, HD64461_GPBDR);

	} else if (intensity) {

		sh_dac_output(255-(u8)intensity, DAC_LCD_BRIGHTNESS);

	}

	spin_unlock_irqrestore(&bl_lock, flags);

	current_intensity = intensity;

}

#ifdef CONFIG_PM

static int hp680bl_suspend(struct platform_device *pdev, pm_message_t state)

{

	struct backlight_device *bd = platform_get_drvdata(pdev);

	hp680bl_suspended = 1;

	hp680bl_send_intensity(bd);

	return 0;

}

static int hp680bl_resume(struct platform_device *pdev)

{

	struct backlight_device *bd = platform_get_drvdata(pdev);

	hp680bl_suspended = 0;

	hp680bl_send_intensity(bd);

	return 0;

}

#else

#define hp680bl_suspend	NULL

#define hp680bl_resume	NULL

#endif

static int hp680bl_set_intensity(struct backlight_device *bd)

{

	hp680bl_send_intensity(bd);

	return 0;

}

static int hp680bl_get_intensity(struct backlight_device *bd)

{

	return current_intensity;

}

static struct backlight_ops hp680bl_ops = {

	.get_brightness = hp680bl_get_intensity,

	.update_status  = hp680bl_set_intensity,

};

static int __devinit hp680bl_probe(struct platform_device *pdev)

{

	struct backlight_device *bd;

	bd = backlight_device_register ("hp680-bl", &pdev->dev, NULL,

		    &hp680bl_ops);

	if (IS_ERR(bd))

		return PTR_ERR(bd);

	platform_set_drvdata(pdev, bd);

	bd->props.max_brightness = HP680_MAX_INTENSITY;

	bd->props.brightness = HP680_DEFAULT_INTENSITY;

	hp680bl_send_intensity(bd);

	return 0;

}

static int hp680bl_remove(struct platform_device *pdev)

{

	struct backlight_device *bd = platform_get_drvdata(pdev);

	bd->props.brightness = 0;

	bd->props.power = 0;

	hp680bl_send_intensity(bd);

	backlight_device_unregister(bd);

	return 0;

}

static struct platform_driver hp680bl_driver = {

	.probe		= hp680bl_probe,

	.remove		= hp680bl_remove,

	.suspend	= hp680bl_suspend,

	.resume		= hp680bl_resume,

	.driver		= {

		.name	= "hp680-bl",

	},

};

static struct platform_device *hp680bl_device;

static int __init hp680bl_init(void)

{

	int ret;

	ret = platform_driver_register(&hp680bl_driver);

	if (ret)

		return ret;

	hp680bl_device = platform_device_register_simple("hp680-bl", -1,

							NULL, 0);

	if (IS_ERR(hp680bl_device)) {

		platform_driver_unregister(&hp680bl_driver);

		return PTR_ERR(hp680bl_device);

	}

	return 0;

}

static void __exit hp680bl_exit(void)

{

	platform_device_unregister(hp680bl_device);

 	platform_driver_unregister(&hp680bl_driver);

}

module_init(hp680bl_init);

module_exit(hp680bl_exit);

MODULE_AUTHOR("Andriy Skulysh <askulysh@gmail.com>");

MODULE_DESCRIPTION("HP Jornada 680 Backlight Driver");

MODULE_LICENSE("GPL");