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path: root/drivers/video/backlight/da903x.c
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Diffstat (limited to 'drivers/video/backlight/da903x.c')
-rw-r--r--drivers/video/backlight/da903x.c201
1 files changed, 201 insertions, 0 deletions
diff --git a/drivers/video/backlight/da903x.c b/drivers/video/backlight/da903x.c
new file mode 100644
index 000000000000..242c38250166
--- /dev/null
+++ b/drivers/video/backlight/da903x.c
@@ -0,0 +1,201 @@
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
34struct da903x_backlight_data {
35 struct device *da903x_dev;
36 int id;
37 int current_brightness;
38};
39
40static 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
78static 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
91static 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
97static struct backlight_ops da903x_backlight_ops = {
98 .update_status = da903x_backlight_update_status,
99 .get_brightness = da903x_backlight_get_brightness,
100};
101
102static 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
144static 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
155static 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
162static 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
174static 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
185static int __init da903x_backlight_init(void)
186{
187 return platform_driver_register(&da903x_backlight_driver);
188}
189module_init(da903x_backlight_init);
190
191static void __exit da903x_backlight_exit(void)
192{
193 platform_driver_unregister(&da903x_backlight_driver);
194}
195module_exit(da903x_backlight_exit);
196
197MODULE_DESCRIPTION("Backlight Driver for Dialog Semiconductor DA9030/DA9034");
198MODULE_AUTHOR("Eric Miao <eric.miao@marvell.com>"
199 "Mike Rapoport <mike@compulab.co.il>");
200MODULE_LICENSE("GPL");
201MODULE_ALIAS("platform:da903x-backlight");