This source file includes following definitions.
- lv5207lp_write
- lv5207lp_backlight_update_status
- lv5207lp_backlight_check_fb
- lv5207lp_probe
- lv5207lp_remove
1
2
3
4
5
6
7
8
9
10 #include <linux/backlight.h>
11 #include <linux/err.h>
12 #include <linux/fb.h>
13 #include <linux/i2c.h>
14 #include <linux/module.h>
15 #include <linux/platform_data/lv5207lp.h>
16 #include <linux/slab.h>
17
18 #define LV5207LP_CTRL1 0x00
19 #define LV5207LP_CPSW (1 << 7)
20 #define LV5207LP_SCTEN (1 << 6)
21 #define LV5207LP_C10 (1 << 5)
22 #define LV5207LP_CKSW (1 << 4)
23 #define LV5207LP_RSW (1 << 3)
24 #define LV5207LP_GSW (1 << 2)
25 #define LV5207LP_BSW (1 << 1)
26 #define LV5207LP_CTRL2 0x01
27 #define LV5207LP_MSW (1 << 7)
28 #define LV5207LP_MLED4 (1 << 6)
29 #define LV5207LP_RED 0x02
30 #define LV5207LP_GREEN 0x03
31 #define LV5207LP_BLUE 0x04
32
33 #define LV5207LP_MAX_BRIGHTNESS 32
34
35 struct lv5207lp {
36 struct i2c_client *client;
37 struct backlight_device *backlight;
38 struct lv5207lp_platform_data *pdata;
39 };
40
41 static int lv5207lp_write(struct lv5207lp *lv, u8 reg, u8 data)
42 {
43 return i2c_smbus_write_byte_data(lv->client, reg, data);
44 }
45
46 static int lv5207lp_backlight_update_status(struct backlight_device *backlight)
47 {
48 struct lv5207lp *lv = bl_get_data(backlight);
49 int brightness = backlight->props.brightness;
50
51 if (backlight->props.power != FB_BLANK_UNBLANK ||
52 backlight->props.fb_blank != FB_BLANK_UNBLANK ||
53 backlight->props.state & (BL_CORE_SUSPENDED | BL_CORE_FBBLANK))
54 brightness = 0;
55
56 if (brightness) {
57 lv5207lp_write(lv, LV5207LP_CTRL1,
58 LV5207LP_CPSW | LV5207LP_C10 | LV5207LP_CKSW);
59 lv5207lp_write(lv, LV5207LP_CTRL2,
60 LV5207LP_MSW | LV5207LP_MLED4 |
61 (brightness - 1));
62 } else {
63 lv5207lp_write(lv, LV5207LP_CTRL1, 0);
64 lv5207lp_write(lv, LV5207LP_CTRL2, 0);
65 }
66
67 return 0;
68 }
69
70 static int lv5207lp_backlight_check_fb(struct backlight_device *backlight,
71 struct fb_info *info)
72 {
73 struct lv5207lp *lv = bl_get_data(backlight);
74
75 return lv->pdata->fbdev == NULL || lv->pdata->fbdev == info->dev;
76 }
77
78 static const struct backlight_ops lv5207lp_backlight_ops = {
79 .options = BL_CORE_SUSPENDRESUME,
80 .update_status = lv5207lp_backlight_update_status,
81 .check_fb = lv5207lp_backlight_check_fb,
82 };
83
84 static int lv5207lp_probe(struct i2c_client *client,
85 const struct i2c_device_id *id)
86 {
87 struct lv5207lp_platform_data *pdata = dev_get_platdata(&client->dev);
88 struct backlight_device *backlight;
89 struct backlight_properties props;
90 struct lv5207lp *lv;
91
92 if (pdata == NULL) {
93 dev_err(&client->dev, "No platform data supplied\n");
94 return -EINVAL;
95 }
96
97 if (!i2c_check_functionality(client->adapter,
98 I2C_FUNC_SMBUS_BYTE_DATA)) {
99 dev_warn(&client->dev,
100 "I2C adapter doesn't support I2C_FUNC_SMBUS_BYTE\n");
101 return -EIO;
102 }
103
104 lv = devm_kzalloc(&client->dev, sizeof(*lv), GFP_KERNEL);
105 if (!lv)
106 return -ENOMEM;
107
108 lv->client = client;
109 lv->pdata = pdata;
110
111 memset(&props, 0, sizeof(props));
112 props.type = BACKLIGHT_RAW;
113 props.max_brightness = min_t(unsigned int, pdata->max_value,
114 LV5207LP_MAX_BRIGHTNESS);
115 props.brightness = clamp_t(unsigned int, pdata->def_value, 0,
116 props.max_brightness);
117
118 backlight = devm_backlight_device_register(&client->dev,
119 dev_name(&client->dev), &lv->client->dev,
120 lv, &lv5207lp_backlight_ops, &props);
121 if (IS_ERR(backlight)) {
122 dev_err(&client->dev, "failed to register backlight\n");
123 return PTR_ERR(backlight);
124 }
125
126 backlight_update_status(backlight);
127 i2c_set_clientdata(client, backlight);
128
129 return 0;
130 }
131
132 static int lv5207lp_remove(struct i2c_client *client)
133 {
134 struct backlight_device *backlight = i2c_get_clientdata(client);
135
136 backlight->props.brightness = 0;
137 backlight_update_status(backlight);
138
139 return 0;
140 }
141
142 static const struct i2c_device_id lv5207lp_ids[] = {
143 { "lv5207lp", 0 },
144 { }
145 };
146 MODULE_DEVICE_TABLE(i2c, lv5207lp_ids);
147
148 static struct i2c_driver lv5207lp_driver = {
149 .driver = {
150 .name = "lv5207lp",
151 },
152 .probe = lv5207lp_probe,
153 .remove = lv5207lp_remove,
154 .id_table = lv5207lp_ids,
155 };
156
157 module_i2c_driver(lv5207lp_driver);
158
159 MODULE_DESCRIPTION("Sanyo LV5207LP Backlight Driver");
160 MODULE_AUTHOR("Laurent Pinchart <laurent.pinchart@ideasonboard.com>");
161 MODULE_LICENSE("GPL");