aboutsummaryrefslogtreecommitdiff
path: root/drivers/video/backlight/platform_lcd.c
blob: 17a6b83f97afdab22abeb065a9c5876d92d3f5b9 (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
/* drivers/video/backlight/platform_lcd.c
 *
 * Copyright 2008 Simtec Electronics
 *	Ben Dooks <ben@simtec.co.uk>
 *
 * Generic platform-device LCD power control interface.
 *
 * 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/platform_device.h>
#include <linux/fb.h>
#include <linux/backlight.h>
#include <linux/lcd.h>
#include <linux/of.h>
#include <linux/slab.h>

#include <video/platform_lcd.h>

struct platform_lcd {
	struct device		*us;
	struct lcd_device	*lcd;
	struct plat_lcd_data	*pdata;

	unsigned int		 power;
	unsigned int		 suspended:1;
};

static inline struct platform_lcd *to_our_lcd(struct lcd_device *lcd)
{
	return lcd_get_data(lcd);
}

static int platform_lcd_get_power(struct lcd_device *lcd)
{
	struct platform_lcd *plcd = to_our_lcd(lcd);

	return plcd->power;
}

static int platform_lcd_set_power(struct lcd_device *lcd, int power)
{
	struct platform_lcd *plcd = to_our_lcd(lcd);
	int lcd_power = 1;

	if (power == FB_BLANK_POWERDOWN || plcd->suspended)
		lcd_power = 0;

	plcd->pdata->set_power(plcd->pdata, lcd_power);
	plcd->power = power;

	return 0;
}

static int platform_lcd_match(struct lcd_device *lcd, struct fb_info *info)
{
	struct platform_lcd *plcd = to_our_lcd(lcd);
	struct plat_lcd_data *pdata = plcd->pdata;

	if (pdata->match_fb)
		return pdata->match_fb(pdata, info);

	return plcd->us->parent == info->device;
}

static struct lcd_ops platform_lcd_ops = {
	.get_power	= platform_lcd_get_power,
	.set_power	= platform_lcd_set_power,
	.check_fb	= platform_lcd_match,
};

static int platform_lcd_probe(struct platform_device *pdev)
{
	struct plat_lcd_data *pdata;
	struct platform_lcd *plcd;
	struct device *dev = &pdev->dev;
	int err;

	pdata = pdev->dev.platform_data;
	if (!pdata) {
		dev_err(dev, "no platform data supplied\n");
		return -EINVAL;
	}

	plcd = devm_kzalloc(&pdev->dev, sizeof(struct platform_lcd),
			    GFP_KERNEL);
	if (!plcd) {
		dev_err(dev, "no memory for state\n");
		return -ENOMEM;
	}

	plcd->us = dev;
	plcd->pdata = pdata;
	plcd->lcd = lcd_device_register(dev_name(dev), dev,
					plcd, &platform_lcd_ops);
	if (IS_ERR(plcd->lcd)) {
		dev_err(dev, "cannot register lcd device\n");
		err = PTR_ERR(plcd->lcd);
		goto err;
	}

	platform_set_drvdata(pdev, plcd);
	platform_lcd_set_power(plcd->lcd, FB_BLANK_NORMAL);

	return 0;

 err:
	return err;
}

static int platform_lcd_remove(struct platform_device *pdev)
{
	struct platform_lcd *plcd = platform_get_drvdata(pdev);

	lcd_device_unregister(plcd->lcd);

	return 0;
}

#ifdef CONFIG_PM
static int platform_lcd_suspend(struct device *dev)
{
	struct platform_lcd *plcd = dev_get_drvdata(dev);

	plcd->suspended = 1;
	platform_lcd_set_power(plcd->lcd, plcd->power);

	return 0;
}

static int platform_lcd_resume(struct device *dev)
{
	struct platform_lcd *plcd = dev_get_drvdata(dev);

	plcd->suspended = 0;
	platform_lcd_set_power(plcd->lcd, plcd->power);

	return 0;
}

static SIMPLE_DEV_PM_OPS(platform_lcd_pm_ops, platform_lcd_suspend,
			platform_lcd_resume);
#endif

#ifdef CONFIG_OF
static const struct of_device_id platform_lcd_of_match[] = {
	{ .compatible = "platform-lcd" },
	{},
};
MODULE_DEVICE_TABLE(of, platform_lcd_of_match);
#endif

static struct platform_driver platform_lcd_driver = {
	.driver		= {
		.name	= "platform-lcd",
		.owner	= THIS_MODULE,
#ifdef CONFIG_PM
		.pm	= &platform_lcd_pm_ops,
#endif
		.of_match_table = of_match_ptr(platform_lcd_of_match),
	},
	.probe		= platform_lcd_probe,
	.remove		= platform_lcd_remove,
};

module_platform_driver(platform_lcd_driver);

MODULE_AUTHOR("Ben Dooks <ben-linux@fluff.org>");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("platform:platform-lcd");