Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6
[linux-2.6] / drivers / video / backlight / da903x.c
1 /*
2  * Backlight driver for Dialog Semiconductor DA9030/DA9034
3  *
4  * Copyright (C) 2008 Compulab, Ltd.
5  *      Mike Rapoport <mike@compulab.co.il>
6  *
7  * Copyright (C) 2006-2008 Marvell International Ltd.
8  *      Eric Miao <eric.miao@marvell.com>
9  *
10  * This program is free software; you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License version 2 as
12  * published by the Free Software Foundation.
13  */
14
15 #include <linux/kernel.h>
16 #include <linux/init.h>
17 #include <linux/platform_device.h>
18 #include <linux/fb.h>
19 #include <linux/backlight.h>
20 #include <linux/mfd/da903x.h>
21
22 #define DA9030_WLED_CONTROL     0x25
23 #define DA9030_WLED_CP_EN       (1 << 6)
24 #define DA9030_WLED_TRIM(x)     ((x) & 0x7)
25
26 #define DA9034_WLED_CONTROL1    0x3C
27 #define DA9034_WLED_CONTROL2    0x3D
28
29 #define DA9034_WLED_BOOST_EN    (1 << 5)
30
31 #define DA9030_MAX_BRIGHTNESS   7
32 #define DA9034_MAX_BRIGHTNESS   0x7f
33
34 struct da903x_backlight_data {
35         struct device *da903x_dev;
36         int id;
37         int current_brightness;
38 };
39
40 static int da903x_backlight_set(struct backlight_device *bl, int brightness)
41 {
42         struct da903x_backlight_data *data = bl_get_data(bl);
43         struct device *dev = data->da903x_dev;
44         uint8_t val;
45         int ret = 0;
46
47         switch (data->id) {
48         case DA9034_ID_WLED:
49                 ret = da903x_update(dev, DA9034_WLED_CONTROL1,
50                                 brightness, 0x7f);
51                 if (ret)
52                         return ret;
53
54                 if (data->current_brightness && brightness == 0)
55                         ret = da903x_clr_bits(dev,
56                                         DA9034_WLED_CONTROL2,
57                                         DA9034_WLED_BOOST_EN);
58
59                 if (data->current_brightness == 0 && brightness)
60                         ret = da903x_set_bits(dev,
61                                         DA9034_WLED_CONTROL2,
62                                         DA9034_WLED_BOOST_EN);
63                 break;
64         case DA9030_ID_WLED:
65                 val = DA9030_WLED_TRIM(brightness);
66                 val |= brightness ? DA9030_WLED_CP_EN : 0;
67                 ret = da903x_write(dev, DA9030_WLED_CONTROL, val);
68                 break;
69         }
70
71         if (ret)
72                 return ret;
73
74         data->current_brightness = brightness;
75         return 0;
76 }
77
78 static int da903x_backlight_update_status(struct backlight_device *bl)
79 {
80         int brightness = bl->props.brightness;
81
82         if (bl->props.power != FB_BLANK_UNBLANK)
83                 brightness = 0;
84
85         if (bl->props.fb_blank != FB_BLANK_UNBLANK)
86                 brightness = 0;
87
88         return da903x_backlight_set(bl, brightness);
89 }
90
91 static int da903x_backlight_get_brightness(struct backlight_device *bl)
92 {
93         struct da903x_backlight_data *data = bl_get_data(bl);
94         return data->current_brightness;
95 }
96
97 static struct backlight_ops da903x_backlight_ops = {
98         .update_status  = da903x_backlight_update_status,
99         .get_brightness = da903x_backlight_get_brightness,
100 };
101
102 static int da903x_backlight_probe(struct platform_device *pdev)
103 {
104         struct da903x_backlight_data *data;
105         struct backlight_device *bl;
106         int max_brightness;
107
108         data = kzalloc(sizeof(*data), GFP_KERNEL);
109         if (data == NULL)
110                 return -ENOMEM;
111
112         switch (pdev->id) {
113         case DA9030_ID_WLED:
114                 max_brightness = DA9030_MAX_BRIGHTNESS;
115                 break;
116         case DA9034_ID_WLED:
117                 max_brightness = DA9034_MAX_BRIGHTNESS;
118                 break;
119         default:
120                 dev_err(&pdev->dev, "invalid backlight device ID(%d)\n",
121                                 pdev->id);
122                 return -EINVAL;
123         }
124
125         data->id = pdev->id;
126         data->da903x_dev = pdev->dev.parent;
127         data->current_brightness = 0;
128
129         bl = backlight_device_register(pdev->name, data->da903x_dev,
130                         data, &da903x_backlight_ops);
131         if (IS_ERR(bl)) {
132                 dev_err(&pdev->dev, "failed to register backlight\n");
133                 return PTR_ERR(bl);
134         }
135
136         bl->props.max_brightness = max_brightness;
137         bl->props.brightness = max_brightness;
138
139         platform_set_drvdata(pdev, bl);
140         backlight_update_status(bl);
141         return 0;
142 }
143
144 static int da903x_backlight_remove(struct platform_device *pdev)
145 {
146         struct backlight_device *bl = platform_get_drvdata(pdev);
147         struct da903x_backlight_data *data = bl_get_data(bl);
148
149         backlight_device_unregister(bl);
150         kfree(data);
151         return 0;
152 }
153
154 #ifdef CONFIG_PM
155 static int da903x_backlight_suspend(struct platform_device *pdev,
156                                  pm_message_t state)
157 {
158         struct backlight_device *bl = platform_get_drvdata(pdev);
159         return da903x_backlight_set(bl, 0);
160 }
161
162 static int da903x_backlight_resume(struct platform_device *pdev)
163 {
164         struct backlight_device *bl = platform_get_drvdata(pdev);
165
166         backlight_update_status(bl);
167         return 0;
168 }
169 #else
170 #define da903x_backlight_suspend        NULL
171 #define da903x_backlight_resume         NULL
172 #endif
173
174 static struct platform_driver da903x_backlight_driver = {
175         .driver         = {
176                 .name   = "da903x-backlight",
177                 .owner  = THIS_MODULE,
178         },
179         .probe          = da903x_backlight_probe,
180         .remove         = da903x_backlight_remove,
181         .suspend        = da903x_backlight_suspend,
182         .resume         = da903x_backlight_resume,
183 };
184
185 static int __init da903x_backlight_init(void)
186 {
187         return platform_driver_register(&da903x_backlight_driver);
188 }
189 module_init(da903x_backlight_init);
190
191 static void __exit da903x_backlight_exit(void)
192 {
193         platform_driver_unregister(&da903x_backlight_driver);
194 }
195 module_exit(da903x_backlight_exit);
196
197 MODULE_DESCRIPTION("Backlight Driver for Dialog Semiconductor DA9030/DA9034");
198 MODULE_AUTHOR("Eric Miao <eric.miao@marvell.com>"
199               "Mike Rapoport <mike@compulab.co.il>");
200 MODULE_LICENSE("GPL");
201 MODULE_ALIAS("platform:da903x-backlight");