1 /* drivers/video/backlight/platform_lcd.c
2 *
3 * Copyright 2008 Simtec Electronics
4 * Ben Dooks <ben@simtec.co.uk>
5 *
6 * Generic platform-device LCD power control interface.
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
11 *
12 */
13
14 #include <linux/module.h>
15 #include <linux/platform_device.h>
16 #include <linux/fb.h>
17 #include <linux/backlight.h>
18 #include <linux/lcd.h>
19 #include <linux/of.h>
20 #include <linux/slab.h>
21
22 #include <video/platform_lcd.h>
23
24 struct platform_lcd {
25 struct device *us;
26 struct lcd_device *lcd;
27 struct plat_lcd_data *pdata;
28
29 unsigned int power;
30 unsigned int suspended:1;
31 };
32
to_our_lcd(struct lcd_device * lcd)33 static inline struct platform_lcd *to_our_lcd(struct lcd_device *lcd)
34 {
35 return lcd_get_data(lcd);
36 }
37
platform_lcd_get_power(struct lcd_device * lcd)38 static int platform_lcd_get_power(struct lcd_device *lcd)
39 {
40 struct platform_lcd *plcd = to_our_lcd(lcd);
41
42 return plcd->power;
43 }
44
platform_lcd_set_power(struct lcd_device * lcd,int power)45 static int platform_lcd_set_power(struct lcd_device *lcd, int power)
46 {
47 struct platform_lcd *plcd = to_our_lcd(lcd);
48 int lcd_power = 1;
49
50 if (power == FB_BLANK_POWERDOWN || plcd->suspended)
51 lcd_power = 0;
52
53 plcd->pdata->set_power(plcd->pdata, lcd_power);
54 plcd->power = power;
55
56 return 0;
57 }
58
platform_lcd_match(struct lcd_device * lcd,struct fb_info * info)59 static int platform_lcd_match(struct lcd_device *lcd, struct fb_info *info)
60 {
61 struct platform_lcd *plcd = to_our_lcd(lcd);
62 struct plat_lcd_data *pdata = plcd->pdata;
63
64 if (pdata->match_fb)
65 return pdata->match_fb(pdata, info);
66
67 return plcd->us->parent == info->device;
68 }
69
70 static struct lcd_ops platform_lcd_ops = {
71 .get_power = platform_lcd_get_power,
72 .set_power = platform_lcd_set_power,
73 .check_fb = platform_lcd_match,
74 };
75
platform_lcd_probe(struct platform_device * pdev)76 static int platform_lcd_probe(struct platform_device *pdev)
77 {
78 struct plat_lcd_data *pdata;
79 struct platform_lcd *plcd;
80 struct device *dev = &pdev->dev;
81 int err;
82
83 pdata = dev_get_platdata(&pdev->dev);
84 if (!pdata) {
85 dev_err(dev, "no platform data supplied\n");
86 return -EINVAL;
87 }
88
89 if (pdata->probe) {
90 err = pdata->probe(pdata);
91 if (err)
92 return err;
93 }
94
95 plcd = devm_kzalloc(&pdev->dev, sizeof(struct platform_lcd),
96 GFP_KERNEL);
97 if (!plcd)
98 return -ENOMEM;
99
100 plcd->us = dev;
101 plcd->pdata = pdata;
102 plcd->lcd = devm_lcd_device_register(&pdev->dev, dev_name(dev), dev,
103 plcd, &platform_lcd_ops);
104 if (IS_ERR(plcd->lcd)) {
105 dev_err(dev, "cannot register lcd device\n");
106 return PTR_ERR(plcd->lcd);
107 }
108
109 platform_set_drvdata(pdev, plcd);
110 platform_lcd_set_power(plcd->lcd, FB_BLANK_NORMAL);
111
112 return 0;
113 }
114
115 #ifdef CONFIG_PM_SLEEP
platform_lcd_suspend(struct device * dev)116 static int platform_lcd_suspend(struct device *dev)
117 {
118 struct platform_lcd *plcd = dev_get_drvdata(dev);
119
120 plcd->suspended = 1;
121 platform_lcd_set_power(plcd->lcd, plcd->power);
122
123 return 0;
124 }
125
platform_lcd_resume(struct device * dev)126 static int platform_lcd_resume(struct device *dev)
127 {
128 struct platform_lcd *plcd = dev_get_drvdata(dev);
129
130 plcd->suspended = 0;
131 platform_lcd_set_power(plcd->lcd, plcd->power);
132
133 return 0;
134 }
135 #endif
136
137 static SIMPLE_DEV_PM_OPS(platform_lcd_pm_ops, platform_lcd_suspend,
138 platform_lcd_resume);
139
140 #ifdef CONFIG_OF
141 static const struct of_device_id platform_lcd_of_match[] = {
142 { .compatible = "platform-lcd" },
143 {},
144 };
145 MODULE_DEVICE_TABLE(of, platform_lcd_of_match);
146 #endif
147
148 static struct platform_driver platform_lcd_driver = {
149 .driver = {
150 .name = "platform-lcd",
151 .pm = &platform_lcd_pm_ops,
152 .of_match_table = of_match_ptr(platform_lcd_of_match),
153 },
154 .probe = platform_lcd_probe,
155 };
156
157 module_platform_driver(platform_lcd_driver);
158
159 MODULE_AUTHOR("Ben Dooks <ben-linux@fluff.org>");
160 MODULE_LICENSE("GPL v2");
161 MODULE_ALIAS("platform:platform-lcd");
162