6891754143d4a0a94ffb176f5681ac3c29f57470
[~shefty/rdma-dev.git] / drivers / video / backlight / da903x_bl.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 #include <linux/slab.h>
22 #include <linux/module.h>
23
24 #define DA9030_WLED_CONTROL     0x25
25 #define DA9030_WLED_CP_EN       (1 << 6)
26 #define DA9030_WLED_TRIM(x)     ((x) & 0x7)
27
28 #define DA9034_WLED_CONTROL1    0x3C
29 #define DA9034_WLED_CONTROL2    0x3D
30 #define DA9034_WLED_ISET(x)     ((x) & 0x1f)
31
32 #define DA9034_WLED_BOOST_EN    (1 << 5)
33
34 #define DA9030_MAX_BRIGHTNESS   7
35 #define DA9034_MAX_BRIGHTNESS   0x7f
36
37 struct da903x_backlight_data {
38         struct device *da903x_dev;
39         int id;
40         int current_brightness;
41 };
42
43 static int da903x_backlight_set(struct backlight_device *bl, int brightness)
44 {
45         struct da903x_backlight_data *data = bl_get_data(bl);
46         struct device *dev = data->da903x_dev;
47         uint8_t val;
48         int ret = 0;
49
50         switch (data->id) {
51         case DA9034_ID_WLED:
52                 ret = da903x_update(dev, DA9034_WLED_CONTROL1,
53                                 brightness, 0x7f);
54                 if (ret)
55                         return ret;
56
57                 if (data->current_brightness && brightness == 0)
58                         ret = da903x_clr_bits(dev,
59                                         DA9034_WLED_CONTROL2,
60                                         DA9034_WLED_BOOST_EN);
61
62                 if (data->current_brightness == 0 && brightness)
63                         ret = da903x_set_bits(dev,
64                                         DA9034_WLED_CONTROL2,
65                                         DA9034_WLED_BOOST_EN);
66                 break;
67         case DA9030_ID_WLED:
68                 val = DA9030_WLED_TRIM(brightness);
69                 val |= brightness ? DA9030_WLED_CP_EN : 0;
70                 ret = da903x_write(dev, DA9030_WLED_CONTROL, val);
71                 break;
72         }
73
74         if (ret)
75                 return ret;
76
77         data->current_brightness = brightness;
78         return 0;
79 }
80
81 static int da903x_backlight_update_status(struct backlight_device *bl)
82 {
83         int brightness = bl->props.brightness;
84
85         if (bl->props.power != FB_BLANK_UNBLANK)
86                 brightness = 0;
87
88         if (bl->props.fb_blank != FB_BLANK_UNBLANK)
89                 brightness = 0;
90
91         return da903x_backlight_set(bl, brightness);
92 }
93
94 static int da903x_backlight_get_brightness(struct backlight_device *bl)
95 {
96         struct da903x_backlight_data *data = bl_get_data(bl);
97         return data->current_brightness;
98 }
99
100 static const struct backlight_ops da903x_backlight_ops = {
101         .update_status  = da903x_backlight_update_status,
102         .get_brightness = da903x_backlight_get_brightness,
103 };
104
105 static int da903x_backlight_probe(struct platform_device *pdev)
106 {
107         struct da9034_backlight_pdata *pdata = pdev->dev.platform_data;
108         struct da903x_backlight_data *data;
109         struct backlight_device *bl;
110         struct backlight_properties props;
111         int max_brightness;
112
113         data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
114         if (data == NULL)
115                 return -ENOMEM;
116
117         switch (pdev->id) {
118         case DA9030_ID_WLED:
119                 max_brightness = DA9030_MAX_BRIGHTNESS;
120                 break;
121         case DA9034_ID_WLED:
122                 max_brightness = DA9034_MAX_BRIGHTNESS;
123                 break;
124         default:
125                 dev_err(&pdev->dev, "invalid backlight device ID(%d)\n",
126                                 pdev->id);
127                 return -EINVAL;
128         }
129
130         data->id = pdev->id;
131         data->da903x_dev = pdev->dev.parent;
132         data->current_brightness = 0;
133
134         /* adjust the WLED output current */
135         if (pdata)
136                 da903x_write(data->da903x_dev, DA9034_WLED_CONTROL2,
137                                 DA9034_WLED_ISET(pdata->output_current));
138
139         memset(&props, 0, sizeof(props));
140         props.type = BACKLIGHT_RAW;
141         props.max_brightness = max_brightness;
142         bl = backlight_device_register(pdev->name, data->da903x_dev, data,
143                                        &da903x_backlight_ops, &props);
144         if (IS_ERR(bl)) {
145                 dev_err(&pdev->dev, "failed to register backlight\n");
146                 return PTR_ERR(bl);
147         }
148
149         bl->props.brightness = max_brightness;
150
151         platform_set_drvdata(pdev, bl);
152         backlight_update_status(bl);
153         return 0;
154 }
155
156 static int da903x_backlight_remove(struct platform_device *pdev)
157 {
158         struct backlight_device *bl = platform_get_drvdata(pdev);
159
160         backlight_device_unregister(bl);
161         return 0;
162 }
163
164 #ifdef CONFIG_PM
165 static int da903x_backlight_suspend(struct device *dev)
166 {
167         struct backlight_device *bl = dev_get_drvdata(dev);
168
169         return da903x_backlight_set(bl, 0);
170 }
171
172 static int da903x_backlight_resume(struct device *dev)
173 {
174         struct backlight_device *bl = dev_get_drvdata(dev);
175
176         backlight_update_status(bl);
177         return 0;
178 }
179
180 static const struct dev_pm_ops da903x_backlight_pm_ops = {
181         .suspend        = da903x_backlight_suspend,
182         .resume         = da903x_backlight_resume,
183 };
184 #endif
185
186 static struct platform_driver da903x_backlight_driver = {
187         .driver         = {
188                 .name   = "da903x-backlight",
189                 .owner  = THIS_MODULE,
190 #ifdef CONFIG_PM
191                 .pm     = &da903x_backlight_pm_ops,
192 #endif
193         },
194         .probe          = da903x_backlight_probe,
195         .remove         = da903x_backlight_remove,
196 };
197
198 module_platform_driver(da903x_backlight_driver);
199
200 MODULE_DESCRIPTION("Backlight Driver for Dialog Semiconductor DA9030/DA9034");
201 MODULE_AUTHOR("Eric Miao <eric.miao@marvell.com>"
202               "Mike Rapoport <mike@compulab.co.il>");
203 MODULE_LICENSE("GPL");
204 MODULE_ALIAS("platform:da903x-backlight");