aboutsummaryrefslogtreecommitdiff
path: root/drivers/video/backlight/corgi_bl.c
blob: 3c72c627e65e99249ceadfbbcc5c8c4d02c8cca4 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
/*
 *  Backlight Driver for Sharp Corgi
 *
 *  Copyright (c) 2004-2005 Richard Purdie
 *
 *  Based on Sharp's 2.4 Backlight Driver
 *
 *  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/device.h>
#include <linux/spinlock.h>
#include <linux/fb.h>
#include <linux/backlight.h>

#include <asm/arch/sharpsl.h>

#define CORGI_DEFAULT_INTENSITY		0x1f
#define CORGI_LIMIT_MASK		0x0b

static int corgibl_powermode = FB_BLANK_UNBLANK;
static int current_intensity = 0;
static int corgibl_limit = 0;
static void (*corgibl_mach_set_intensity)(int intensity);
static spinlock_t bl_lock = SPIN_LOCK_UNLOCKED;
static struct backlight_properties corgibl_data;

static void corgibl_send_intensity(int intensity)
{
	unsigned long flags;
	void (*corgi_kick_batt)(void);

	if (corgibl_powermode != FB_BLANK_UNBLANK) {
		intensity = 0;
	} else {
		if (corgibl_limit)
			intensity &= CORGI_LIMIT_MASK;
	}

	spin_lock_irqsave(&bl_lock, flags);

	corgibl_mach_set_intensity(intensity);

	spin_unlock_irqrestore(&bl_lock, flags);
}

static void corgibl_blank(int blank)
{
	switch(blank) {

	case FB_BLANK_NORMAL:
	case FB_BLANK_VSYNC_SUSPEND:
	case FB_BLANK_HSYNC_SUSPEND:
	case FB_BLANK_POWERDOWN:
		if (corgibl_powermode == FB_BLANK_UNBLANK) {
			corgibl_send_intensity(0);
			corgibl_powermode = blank;
		}
		break;
	case FB_BLANK_UNBLANK:
		if (corgibl_powermode != FB_BLANK_UNBLANK) {
			corgibl_powermode = blank;
			corgibl_send_intensity(current_intensity);
		}
		break;
	}
}

#ifdef CONFIG_PM
static int corgibl_suspend(struct device *dev, pm_message_t state, u32 level)
{
	if (level == SUSPEND_POWER_DOWN)
		corgibl_blank(FB_BLANK_POWERDOWN);
	return 0;
}

static int corgibl_resume(struct device *dev, u32 level)
{
	if (level == RESUME_POWER_ON)
		corgibl_blank(FB_BLANK_UNBLANK);
	return 0;
}
#else
#define corgibl_suspend	NULL
#define corgibl_resume	NULL
#endif


static int corgibl_set_power(struct backlight_device *bd, int state)
{
	corgibl_blank(state);
	return 0;
}

static int corgibl_get_power(struct backlight_device *bd)
{
	return corgibl_powermode;
}

static int corgibl_set_intensity(struct backlight_device *bd, int intensity)
{
	if (intensity > corgibl_data.max_brightness)
		intensity = corgibl_data.max_brightness;
	corgibl_send_intensity(intensity);
	current_intensity=intensity;
	return 0;
}

static int corgibl_get_intensity(struct backlight_device *bd)
{
	return current_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)
{
	corgibl_limit = (limit ? 1 : 0);
	corgibl_send_intensity(current_intensity);
}
EXPORT_SYMBOL(corgibl_limit_intensity);


static struct backlight_properties corgibl_data = {
	.owner		= THIS_MODULE,
	.get_power      = corgibl_get_power,
	.set_power      = corgibl_set_power,
	.get_brightness = corgibl_get_intensity,
	.set_brightness = corgibl_set_intensity,
};

static struct backlight_device *corgi_backlight_device;

static int __init corgibl_probe(struct device *dev)
{
	struct corgibl_machinfo *machinfo = dev->platform_data;

	corgibl_data.max_brightness = machinfo->max_intensity;
	corgibl_mach_set_intensity = machinfo->set_bl_intensity;

	corgi_backlight_device = backlight_device_register ("corgi-bl",
		NULL, &corgibl_data);
	if (IS_ERR (corgi_backlight_device))
		return PTR_ERR (corgi_backlight_device);

	corgibl_set_intensity(NULL, CORGI_DEFAULT_INTENSITY);
	corgibl_limit_intensity(0);

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

static int corgibl_remove(struct device *dev)
{
	backlight_device_unregister(corgi_backlight_device);

	corgibl_set_intensity(NULL, 0);

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

static struct device_driver corgibl_driver = {
	.name		= "corgi-bl",
	.bus		= &platform_bus_type,
	.probe		= corgibl_probe,
	.remove		= corgibl_remove,
	.suspend	= corgibl_suspend,
	.resume		= corgibl_resume,
};

static int __init corgibl_init(void)
{
	return driver_register(&corgibl_driver);
}

static void __exit corgibl_exit(void)
{
 	driver_unregister(&corgibl_driver);
}

module_init(corgibl_init);
module_exit(corgibl_exit);

MODULE_AUTHOR("Richard Purdie <rpurdie@rpsys.net>");
MODULE_DESCRIPTION("Corgi Backlight Driver");
MODULE_LICENSE("GPLv2");