1 /*
2 * ROHM Semiconductor BD6107 LED Driver
3 *
4 * Copyright (C) 2013 Ideas on board SPRL
5 *
6 * Contact: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
11 */
12
13 #include <linux/backlight.h>
14 #include <linux/delay.h>
15 #include <linux/err.h>
16 #include <linux/fb.h>
17 #include <linux/gpio.h>
18 #include <linux/i2c.h>
19 #include <linux/module.h>
20 #include <linux/platform_data/bd6107.h>
21 #include <linux/slab.h>
22
23 #define BD6107_PSCNT1 0x00
24 #define BD6107_PSCNT1_PSCNTREG2 (1 << 2)
25 #define BD6107_PSCNT1_PSCNTREG1 (1 << 0)
26 #define BD6107_REGVSET 0x02
27 #define BD6107_REGVSET_REG1VSET_2_85V (1 << 2)
28 #define BD6107_REGVSET_REG1VSET_2_80V (0 << 2)
29 #define BD6107_LEDCNT1 0x03
30 #define BD6107_LEDCNT1_LEDONOFF2 (1 << 1)
31 #define BD6107_LEDCNT1_LEDONOFF1 (1 << 0)
32 #define BD6107_PORTSEL 0x04
33 #define BD6107_PORTSEL_LEDM(n) (1 << (n))
34 #define BD6107_RGB1CNT1 0x05
35 #define BD6107_RGB1CNT2 0x06
36 #define BD6107_RGB1CNT3 0x07
37 #define BD6107_RGB1CNT4 0x08
38 #define BD6107_RGB1CNT5 0x09
39 #define BD6107_RGB1FLM 0x0a
40 #define BD6107_RGB2CNT1 0x0b
41 #define BD6107_RGB2CNT2 0x0c
42 #define BD6107_RGB2CNT3 0x0d
43 #define BD6107_RGB2CNT4 0x0e
44 #define BD6107_RGB2CNT5 0x0f
45 #define BD6107_RGB2FLM 0x10
46 #define BD6107_PSCONT3 0x11
47 #define BD6107_SMMONCNT 0x12
48 #define BD6107_DCDCCNT 0x13
49 #define BD6107_IOSEL 0x14
50 #define BD6107_OUT1 0x15
51 #define BD6107_OUT2 0x16
52 #define BD6107_MASK1 0x17
53 #define BD6107_MASK2 0x18
54 #define BD6107_FACTOR1 0x19
55 #define BD6107_FACTOR2 0x1a
56 #define BD6107_CLRFACT1 0x1b
57 #define BD6107_CLRFACT2 0x1c
58 #define BD6107_STATE1 0x1d
59 #define BD6107_LSIVER 0x1e
60 #define BD6107_GRPSEL 0x1f
61 #define BD6107_LEDCNT2 0x20
62 #define BD6107_LEDCNT3 0x21
63 #define BD6107_MCURRENT 0x22
64 #define BD6107_MAINCNT1 0x23
65 #define BD6107_MAINCNT2 0x24
66 #define BD6107_SLOPECNT 0x25
67 #define BD6107_MSLOPE 0x26
68 #define BD6107_RGBSLOPE 0x27
69 #define BD6107_TEST 0x29
70 #define BD6107_SFTRST 0x2a
71 #define BD6107_SFTRSTGD 0x2b
72
73 struct bd6107 {
74 struct i2c_client *client;
75 struct backlight_device *backlight;
76 struct bd6107_platform_data *pdata;
77 };
78
bd6107_write(struct bd6107 * bd,u8 reg,u8 data)79 static int bd6107_write(struct bd6107 *bd, u8 reg, u8 data)
80 {
81 return i2c_smbus_write_byte_data(bd->client, reg, data);
82 }
83
bd6107_backlight_update_status(struct backlight_device * backlight)84 static int bd6107_backlight_update_status(struct backlight_device *backlight)
85 {
86 struct bd6107 *bd = bl_get_data(backlight);
87 int brightness = backlight->props.brightness;
88
89 if (backlight->props.power != FB_BLANK_UNBLANK ||
90 backlight->props.fb_blank != FB_BLANK_UNBLANK ||
91 backlight->props.state & (BL_CORE_SUSPENDED | BL_CORE_FBBLANK))
92 brightness = 0;
93
94 if (brightness) {
95 bd6107_write(bd, BD6107_PORTSEL, BD6107_PORTSEL_LEDM(2) |
96 BD6107_PORTSEL_LEDM(1) | BD6107_PORTSEL_LEDM(0));
97 bd6107_write(bd, BD6107_MAINCNT1, brightness);
98 bd6107_write(bd, BD6107_LEDCNT1, BD6107_LEDCNT1_LEDONOFF1);
99 } else {
100 gpio_set_value(bd->pdata->reset, 0);
101 msleep(24);
102 gpio_set_value(bd->pdata->reset, 1);
103 }
104
105 return 0;
106 }
107
bd6107_backlight_check_fb(struct backlight_device * backlight,struct fb_info * info)108 static int bd6107_backlight_check_fb(struct backlight_device *backlight,
109 struct fb_info *info)
110 {
111 struct bd6107 *bd = bl_get_data(backlight);
112
113 return bd->pdata->fbdev == NULL || bd->pdata->fbdev == info->dev;
114 }
115
116 static const struct backlight_ops bd6107_backlight_ops = {
117 .options = BL_CORE_SUSPENDRESUME,
118 .update_status = bd6107_backlight_update_status,
119 .check_fb = bd6107_backlight_check_fb,
120 };
121
bd6107_probe(struct i2c_client * client,const struct i2c_device_id * id)122 static int bd6107_probe(struct i2c_client *client,
123 const struct i2c_device_id *id)
124 {
125 struct bd6107_platform_data *pdata = dev_get_platdata(&client->dev);
126 struct backlight_device *backlight;
127 struct backlight_properties props;
128 struct bd6107 *bd;
129 int ret;
130
131 if (pdata == NULL || !pdata->reset) {
132 dev_err(&client->dev, "No reset GPIO in platform data\n");
133 return -EINVAL;
134 }
135
136 if (!i2c_check_functionality(client->adapter,
137 I2C_FUNC_SMBUS_BYTE_DATA)) {
138 dev_warn(&client->dev,
139 "I2C adapter doesn't support I2C_FUNC_SMBUS_BYTE\n");
140 return -EIO;
141 }
142
143 bd = devm_kzalloc(&client->dev, sizeof(*bd), GFP_KERNEL);
144 if (!bd)
145 return -ENOMEM;
146
147 bd->client = client;
148 bd->pdata = pdata;
149
150 ret = devm_gpio_request_one(&client->dev, pdata->reset,
151 GPIOF_DIR_OUT | GPIOF_INIT_LOW, "reset");
152 if (ret < 0) {
153 dev_err(&client->dev, "unable to request reset GPIO\n");
154 return ret;
155 }
156
157 memset(&props, 0, sizeof(props));
158 props.type = BACKLIGHT_RAW;
159 props.max_brightness = 128;
160 props.brightness = clamp_t(unsigned int, pdata->def_value, 0,
161 props.max_brightness);
162
163 backlight = devm_backlight_device_register(&client->dev,
164 dev_name(&client->dev),
165 &bd->client->dev, bd,
166 &bd6107_backlight_ops, &props);
167 if (IS_ERR(backlight)) {
168 dev_err(&client->dev, "failed to register backlight\n");
169 return PTR_ERR(backlight);
170 }
171
172 backlight_update_status(backlight);
173 i2c_set_clientdata(client, backlight);
174
175 return 0;
176 }
177
bd6107_remove(struct i2c_client * client)178 static int bd6107_remove(struct i2c_client *client)
179 {
180 struct backlight_device *backlight = i2c_get_clientdata(client);
181
182 backlight->props.brightness = 0;
183 backlight_update_status(backlight);
184
185 return 0;
186 }
187
188 static const struct i2c_device_id bd6107_ids[] = {
189 { "bd6107", 0 },
190 { }
191 };
192 MODULE_DEVICE_TABLE(i2c, bd6107_ids);
193
194 static struct i2c_driver bd6107_driver = {
195 .driver = {
196 .name = "bd6107",
197 },
198 .probe = bd6107_probe,
199 .remove = bd6107_remove,
200 .id_table = bd6107_ids,
201 };
202
203 module_i2c_driver(bd6107_driver);
204
205 MODULE_DESCRIPTION("Rohm BD6107 Backlight Driver");
206 MODULE_AUTHOR("Laurent Pinchart <laurent.pinchart@ideasonboard.com>");
207 MODULE_LICENSE("GPL");
208
