[mirror_ubuntu-bionic-kernel.git] / drivers / video / backlight / generic_bl.c

/*
 *  Generic Backlight Driver
 *
 *  Copyright (c) 2004-2008 Richard Purdie
 *
 *  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/kernel.h>
#include <linux/init.h>
#include <linux/platform_device.h>
#include <linux/mutex.h>
#include <linux/fb.h>
#include <linux/backlight.h>

static int genericbl_intensity;
static struct backlight_device *generic_backlight_device;
static struct generic_bl_info *bl_machinfo;

/* Flag to signal when the battery is low */
#define GENERICBL_BATTLOW       BL_CORE_DRIVER1

static int genericbl_send_intensity(struct backlight_device *bd)
{
	int intensity = bd->props.brightness;

	if (bd->props.power != FB_BLANK_UNBLANK)
		intensity = 0;
	if (bd->props.state & BL_CORE_FBBLANK)
		intensity = 0;
	if (bd->props.state & BL_CORE_SUSPENDED)
		intensity = 0;
	if (bd->props.state & GENERICBL_BATTLOW)
		intensity &= bl_machinfo->limit_mask;

	bl_machinfo->set_bl_intensity(intensity);

	genericbl_intensity = intensity;

	if (bl_machinfo->kick_battery)
		bl_machinfo->kick_battery();

	return 0;
}

static int genericbl_get_intensity(struct backlight_device *bd)
{
	return genericbl_intensity;
}

/*
 * Called when the battery is low to limit the backlight intensity.
 * If limit==0 clear any limit, otherwise limit the intensity
 */
void corgibl_limit_intensity(int limit)
{
	struct backlight_device *bd = generic_backlight_device;

	mutex_lock(&bd->ops_lock);
	if (limit)
		bd->props.state |= GENERICBL_BATTLOW;
	else
		bd->props.state &= ~GENERICBL_BATTLOW;
	backlight_update_status(generic_backlight_device);
	mutex_unlock(&bd->ops_lock);
}
EXPORT_SYMBOL(corgibl_limit_intensity);

static struct backlight_ops genericbl_ops = {
	.options = BL_CORE_SUSPENDRESUME,
	.get_brightness = genericbl_get_intensity,
	.update_status  = genericbl_send_intensity,
};

static int genericbl_probe(struct platform_device *pdev)
{
	struct generic_bl_info *machinfo = pdev->dev.platform_data;
	const char *name = "generic-bl";
	struct backlight_device *bd;

	bl_machinfo = machinfo;
	if (!machinfo->limit_mask)
		machinfo->limit_mask = -1;

	if (machinfo->name)
		name = machinfo->name;

	bd = backlight_device_register (name,
		&pdev->dev, NULL, &genericbl_ops);
	if (IS_ERR (bd))
		return PTR_ERR (bd);

	platform_set_drvdata(pdev, bd);

	bd->props.max_brightness = machinfo->max_intensity;
	bd->props.power = FB_BLANK_UNBLANK;
	bd->props.brightness = machinfo->default_intensity;
	backlight_update_status(bd);

	generic_backlight_device = bd;

	printk("Generic Backlight Driver Initialized.\n");
	return 0;
}

static int genericbl_remove(struct platform_device *pdev)
{
	struct backlight_device *bd = platform_get_drvdata(pdev);

	bd->props.power = 0;
	bd->props.brightness = 0;
	backlight_update_status(bd);

	backlight_device_unregister(bd);

	printk("Generic Backlight Driver Unloaded\n");
	return 0;
}

static struct platform_driver genericbl_driver = {
	.probe		= genericbl_probe,
	.remove		= genericbl_remove,
	.driver		= {
		.name	= "generic-bl",
	},
};

static int __init genericbl_init(void)
{
	return platform_driver_register(&genericbl_driver);
}

static void __exit genericbl_exit(void)
{
	platform_driver_unregister(&genericbl_driver);
}

module_init(genericbl_init);
module_exit(genericbl_exit);

MODULE_AUTHOR("Richard Purdie <rpurdie@rpsys.net>");
MODULE_DESCRIPTION("Generic Backlight Driver");
MODULE_LICENSE("GPL");
Commit	Line	Data
d00ba726 RP	1	/*
	2	* Generic Backlight Driver
	3	*
	4	* Copyright (c) 2004-2008 Richard Purdie
	5	*
	6	* This program is free software; you can redistribute it and/or modify
	7	* it under the terms of the GNU General Public License version 2 as
	8	* published by the Free Software Foundation.
	9	*
	10	*/
	11
	12	#include <linux/module.h>
	13	#include <linux/kernel.h>
	14	#include <linux/init.h>
	15	#include <linux/platform_device.h>
	16	#include <linux/mutex.h>
	17	#include <linux/fb.h>
	18	#include <linux/backlight.h>
	19
	20	static int genericbl_intensity;
	21	static struct backlight_device *generic_backlight_device;
	22	static struct generic_bl_info *bl_machinfo;
	23
	24	/* Flag to signal when the battery is low */
	25	#define GENERICBL_BATTLOW BL_CORE_DRIVER1
	26
	27	static int genericbl_send_intensity(struct backlight_device *bd)
	28	{
	29	int intensity = bd->props.brightness;
	30
	31	if (bd->props.power != FB_BLANK_UNBLANK)
	32	intensity = 0;
	33	if (bd->props.state & BL_CORE_FBBLANK)
	34	intensity = 0;
	35	if (bd->props.state & BL_CORE_SUSPENDED)
	36	intensity = 0;
	37	if (bd->props.state & GENERICBL_BATTLOW)
	38	intensity &= bl_machinfo->limit_mask;
	39
	40	bl_machinfo->set_bl_intensity(intensity);
	41
	42	genericbl_intensity = intensity;
	43
	44	if (bl_machinfo->kick_battery)
	45	bl_machinfo->kick_battery();
	46
	47	return 0;
	48	}
	49
	50	static int genericbl_get_intensity(struct backlight_device *bd)
	51	{
	52	return genericbl_intensity;
	53	}
	54
	55	/*
	56	* Called when the battery is low to limit the backlight intensity.
	57	* If limit==0 clear any limit, otherwise limit the intensity
	58	*/
	59	void corgibl_limit_intensity(int limit)
	60	{
	61	struct backlight_device *bd = generic_backlight_device;
	62
	63	mutex_lock(&bd->ops_lock);
	64	if (limit)
65	bd->props.state \|= GENERICBL_BATTLOW;
66	else
67	bd->props.state &= ~GENERICBL_BATTLOW;
68	backlight_update_status(generic_backlight_device);
69	mutex_unlock(&bd->ops_lock);
70	}
71	EXPORT_SYMBOL(corgibl_limit_intensity);
72
73	static struct backlight_ops genericbl_ops = {
74	.options = BL_CORE_SUSPENDRESUME,
75	.get_brightness = genericbl_get_intensity,
76	.update_status = genericbl_send_intensity,
77	};
78
79	static int genericbl_probe(struct platform_device *pdev)
80	{
81	struct generic_bl_info *machinfo = pdev->dev.platform_data;
82	const char *name = "generic-bl";
83	struct backlight_device *bd;
84
85	bl_machinfo = machinfo;
86	if (!machinfo->limit_mask)
87	machinfo->limit_mask = -1;
88
89	if (machinfo->name)
90	name = machinfo->name;
91
92	bd = backlight_device_register (name,
93	&pdev->dev, NULL, &genericbl_ops);
94	if (IS_ERR (bd))
95	return PTR_ERR (bd);
96
97	platform_set_drvdata(pdev, bd);
98
99	bd->props.max_brightness = machinfo->max_intensity;
100	bd->props.power = FB_BLANK_UNBLANK;
101	bd->props.brightness = machinfo->default_intensity;
102	backlight_update_status(bd);
103
104	generic_backlight_device = bd;
105
106	printk("Generic Backlight Driver Initialized.\n");
107	return 0;
108	}
109
110	static int genericbl_remove(struct platform_device *pdev)
111	{
112	struct backlight_device *bd = platform_get_drvdata(pdev);
113
114	bd->props.power = 0;
115	bd->props.brightness = 0;
116	backlight_update_status(bd);
117
118	backlight_device_unregister(bd);
119
120	printk("Generic Backlight Driver Unloaded\n");
121	return 0;
122	}
123
124	static struct platform_driver genericbl_driver = {
125	.probe = genericbl_probe,
126	.remove = genericbl_remove,
127	.driver = {
128	.name = "generic-bl",
129	},
130	};
131
132	static int __init genericbl_init(void)
133	{
134	return platform_driver_register(&genericbl_driver);
135	}
136
137	static void __exit genericbl_exit(void)
138	{
139	platform_driver_unregister(&genericbl_driver);
140	}
141
142	module_init(genericbl_init);
143	module_exit(genericbl_exit);
144
145	MODULE_AUTHOR("Richard Purdie <rpurdie@rpsys.net>");
146	MODULE_DESCRIPTION("Generic Backlight Driver");
147	MODULE_LICENSE("GPL");