1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Sanyo LV5207LP LED Driver
4 *
5 * Copyright (C) 2013 Ideas on board SPRL
6 *
7 * Contact: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
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
lv5207lp_write(struct lv5207lp * lv,u8 reg,u8 data)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
lv5207lp_backlight_update_status(struct backlight_device * backlight)46 static int lv5207lp_backlight_update_status(struct backlight_device *backlight)
47 {
48 struct lv5207lp *lv = bl_get_data(backlight);
49 int brightness = backlight_get_brightness(backlight);
50
51 if (brightness) {
52 lv5207lp_write(lv, LV5207LP_CTRL1,
53 LV5207LP_CPSW | LV5207LP_C10 | LV5207LP_CKSW);
54 lv5207lp_write(lv, LV5207LP_CTRL2,
55 LV5207LP_MSW | LV5207LP_MLED4 |
56 (brightness - 1));
57 } else {
58 lv5207lp_write(lv, LV5207LP_CTRL1, 0);
59 lv5207lp_write(lv, LV5207LP_CTRL2, 0);
60 }
61
62 return 0;
63 }
64
lv5207lp_backlight_check_fb(struct backlight_device * backlight,struct fb_info * info)65 static int lv5207lp_backlight_check_fb(struct backlight_device *backlight,
66 struct fb_info *info)
67 {
68 struct lv5207lp *lv = bl_get_data(backlight);
69
70 return lv->pdata->fbdev == NULL || lv->pdata->fbdev == info->device;
71 }
72
73 static const struct backlight_ops lv5207lp_backlight_ops = {
74 .options = BL_CORE_SUSPENDRESUME,
75 .update_status = lv5207lp_backlight_update_status,
76 .check_fb = lv5207lp_backlight_check_fb,
77 };
78
lv5207lp_probe(struct i2c_client * client,const struct i2c_device_id * id)79 static int lv5207lp_probe(struct i2c_client *client,
80 const struct i2c_device_id *id)
81 {
82 struct lv5207lp_platform_data *pdata = dev_get_platdata(&client->dev);
83 struct backlight_device *backlight;
84 struct backlight_properties props;
85 struct lv5207lp *lv;
86
87 if (pdata == NULL) {
88 dev_err(&client->dev, "No platform data supplied\n");
89 return -EINVAL;
90 }
91
92 if (!i2c_check_functionality(client->adapter,
93 I2C_FUNC_SMBUS_BYTE_DATA)) {
94 dev_warn(&client->dev,
95 "I2C adapter doesn't support I2C_FUNC_SMBUS_BYTE\n");
96 return -EIO;
97 }
98
99 lv = devm_kzalloc(&client->dev, sizeof(*lv), GFP_KERNEL);
100 if (!lv)
101 return -ENOMEM;
102
103 lv->client = client;
104 lv->pdata = pdata;
105
106 memset(&props, 0, sizeof(props));
107 props.type = BACKLIGHT_RAW;
108 props.max_brightness = min_t(unsigned int, pdata->max_value,
109 LV5207LP_MAX_BRIGHTNESS);
110 props.brightness = clamp_t(unsigned int, pdata->def_value, 0,
111 props.max_brightness);
112
113 backlight = devm_backlight_device_register(&client->dev,
114 dev_name(&client->dev), &lv->client->dev,
115 lv, &lv5207lp_backlight_ops, &props);
116 if (IS_ERR(backlight)) {
117 dev_err(&client->dev, "failed to register backlight\n");
118 return PTR_ERR(backlight);
119 }
120
121 backlight_update_status(backlight);
122 i2c_set_clientdata(client, backlight);
123
124 return 0;
125 }
126
lv5207lp_remove(struct i2c_client * client)127 static int lv5207lp_remove(struct i2c_client *client)
128 {
129 struct backlight_device *backlight = i2c_get_clientdata(client);
130
131 backlight->props.brightness = 0;
132 backlight_update_status(backlight);
133
134 return 0;
135 }
136
137 static const struct i2c_device_id lv5207lp_ids[] = {
138 { "lv5207lp", 0 },
139 { }
140 };
141 MODULE_DEVICE_TABLE(i2c, lv5207lp_ids);
142
143 static struct i2c_driver lv5207lp_driver = {
144 .driver = {
145 .name = "lv5207lp",
146 },
147 .probe = lv5207lp_probe,
148 .remove = lv5207lp_remove,
149 .id_table = lv5207lp_ids,
150 };
151
152 module_i2c_driver(lv5207lp_driver);
153
154 MODULE_DESCRIPTION("Sanyo LV5207LP Backlight Driver");
155 MODULE_AUTHOR("Laurent Pinchart <laurent.pinchart@ideasonboard.com>");
156 MODULE_LICENSE("GPL");
157