1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * ROHM Semiconductor BD6107 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/delay.h>
12 #include <linux/err.h>
13 #include <linux/fb.h>
14 #include <linux/gpio/consumer.h>
15 #include <linux/i2c.h>
16 #include <linux/module.h>
17 #include <linux/platform_data/bd6107.h>
18 #include <linux/slab.h>
19
20 #define BD6107_PSCNT1 0x00
21 #define BD6107_PSCNT1_PSCNTREG2 (1 << 2)
22 #define BD6107_PSCNT1_PSCNTREG1 (1 << 0)
23 #define BD6107_REGVSET 0x02
24 #define BD6107_REGVSET_REG1VSET_2_85V (1 << 2)
25 #define BD6107_REGVSET_REG1VSET_2_80V (0 << 2)
26 #define BD6107_LEDCNT1 0x03
27 #define BD6107_LEDCNT1_LEDONOFF2 (1 << 1)
28 #define BD6107_LEDCNT1_LEDONOFF1 (1 << 0)
29 #define BD6107_PORTSEL 0x04
30 #define BD6107_PORTSEL_LEDM(n) (1 << (n))
31 #define BD6107_RGB1CNT1 0x05
32 #define BD6107_RGB1CNT2 0x06
33 #define BD6107_RGB1CNT3 0x07
34 #define BD6107_RGB1CNT4 0x08
35 #define BD6107_RGB1CNT5 0x09
36 #define BD6107_RGB1FLM 0x0a
37 #define BD6107_RGB2CNT1 0x0b
38 #define BD6107_RGB2CNT2 0x0c
39 #define BD6107_RGB2CNT3 0x0d
40 #define BD6107_RGB2CNT4 0x0e
41 #define BD6107_RGB2CNT5 0x0f
42 #define BD6107_RGB2FLM 0x10
43 #define BD6107_PSCONT3 0x11
44 #define BD6107_SMMONCNT 0x12
45 #define BD6107_DCDCCNT 0x13
46 #define BD6107_IOSEL 0x14
47 #define BD6107_OUT1 0x15
48 #define BD6107_OUT2 0x16
49 #define BD6107_MASK1 0x17
50 #define BD6107_MASK2 0x18
51 #define BD6107_FACTOR1 0x19
52 #define BD6107_FACTOR2 0x1a
53 #define BD6107_CLRFACT1 0x1b
54 #define BD6107_CLRFACT2 0x1c
55 #define BD6107_STATE1 0x1d
56 #define BD6107_LSIVER 0x1e
57 #define BD6107_GRPSEL 0x1f
58 #define BD6107_LEDCNT2 0x20
59 #define BD6107_LEDCNT3 0x21
60 #define BD6107_MCURRENT 0x22
61 #define BD6107_MAINCNT1 0x23
62 #define BD6107_MAINCNT2 0x24
63 #define BD6107_SLOPECNT 0x25
64 #define BD6107_MSLOPE 0x26
65 #define BD6107_RGBSLOPE 0x27
66 #define BD6107_TEST 0x29
67 #define BD6107_SFTRST 0x2a
68 #define BD6107_SFTRSTGD 0x2b
69
70 struct bd6107 {
71 struct i2c_client *client;
72 struct backlight_device *backlight;
73 struct bd6107_platform_data *pdata;
74 struct gpio_desc *reset;
75 };
76
bd6107_write(struct bd6107 * bd,u8 reg,u8 data)77 static int bd6107_write(struct bd6107 *bd, u8 reg, u8 data)
78 {
79 return i2c_smbus_write_byte_data(bd->client, reg, data);
80 }
81
bd6107_backlight_update_status(struct backlight_device * backlight)82 static int bd6107_backlight_update_status(struct backlight_device *backlight)
83 {
84 struct bd6107 *bd = bl_get_data(backlight);
85 int brightness = backlight_get_brightness(backlight);
86
87 if (brightness) {
88 bd6107_write(bd, BD6107_PORTSEL, BD6107_PORTSEL_LEDM(2) |
89 BD6107_PORTSEL_LEDM(1) | BD6107_PORTSEL_LEDM(0));
90 bd6107_write(bd, BD6107_MAINCNT1, brightness);
91 bd6107_write(bd, BD6107_LEDCNT1, BD6107_LEDCNT1_LEDONOFF1);
92 } else {
93 /* Assert the reset line (gpiolib will handle active low) */
94 gpiod_set_value(bd->reset, 1);
95 msleep(24);
96 gpiod_set_value(bd->reset, 0);
97 }
98
99 return 0;
100 }
101
bd6107_backlight_controls_device(struct backlight_device * backlight,struct device * display_dev)102 static bool bd6107_backlight_controls_device(struct backlight_device *backlight,
103 struct device *display_dev)
104 {
105 struct bd6107 *bd = bl_get_data(backlight);
106
107 return !bd->pdata->dev || bd->pdata->dev == display_dev;
108 }
109
110 static const struct backlight_ops bd6107_backlight_ops = {
111 .options = BL_CORE_SUSPENDRESUME,
112 .update_status = bd6107_backlight_update_status,
113 .controls_device = bd6107_backlight_controls_device,
114 };
115
bd6107_probe(struct i2c_client * client)116 static int bd6107_probe(struct i2c_client *client)
117 {
118 struct bd6107_platform_data *pdata = dev_get_platdata(&client->dev);
119 struct backlight_device *backlight;
120 struct backlight_properties props;
121 struct bd6107 *bd;
122
123 if (pdata == NULL) {
124 dev_err(&client->dev, "No platform data\n");
125 return -EINVAL;
126 }
127
128 if (!i2c_check_functionality(client->adapter,
129 I2C_FUNC_SMBUS_BYTE_DATA)) {
130 dev_warn(&client->dev,
131 "I2C adapter doesn't support I2C_FUNC_SMBUS_BYTE\n");
132 return -EIO;
133 }
134
135 bd = devm_kzalloc(&client->dev, sizeof(*bd), GFP_KERNEL);
136 if (!bd)
137 return -ENOMEM;
138
139 bd->client = client;
140 bd->pdata = pdata;
141
142 /*
143 * Request the reset GPIO line with GPIOD_OUT_HIGH meaning asserted,
144 * so in the machine descriptor table (or other hardware description),
145 * the line should be flagged as active low so this will assert
146 * the reset.
147 */
148 bd->reset = devm_gpiod_get(&client->dev, "reset", GPIOD_OUT_HIGH);
149 if (IS_ERR(bd->reset))
150 return dev_err_probe(&client->dev, PTR_ERR(bd->reset),
151 "unable to request reset GPIO\n");
152
153 memset(&props, 0, sizeof(props));
154 props.type = BACKLIGHT_RAW;
155 props.max_brightness = 128;
156 props.brightness = clamp_t(unsigned int, pdata->def_value, 0,
157 props.max_brightness);
158
159 backlight = devm_backlight_device_register(&client->dev,
160 dev_name(&client->dev),
161 &bd->client->dev, bd,
162 &bd6107_backlight_ops, &props);
163 if (IS_ERR(backlight)) {
164 dev_err(&client->dev, "failed to register backlight\n");
165 return PTR_ERR(backlight);
166 }
167
168 backlight_update_status(backlight);
169 i2c_set_clientdata(client, backlight);
170
171 return 0;
172 }
173
bd6107_remove(struct i2c_client * client)174 static void bd6107_remove(struct i2c_client *client)
175 {
176 struct backlight_device *backlight = i2c_get_clientdata(client);
177
178 backlight->props.brightness = 0;
179 backlight_update_status(backlight);
180 }
181
182 static const struct i2c_device_id bd6107_ids[] = {
183 { "bd6107" },
184 { }
185 };
186 MODULE_DEVICE_TABLE(i2c, bd6107_ids);
187
188 static struct i2c_driver bd6107_driver = {
189 .driver = {
190 .name = "bd6107",
191 },
192 .probe = bd6107_probe,
193 .remove = bd6107_remove,
194 .id_table = bd6107_ids,
195 };
196
197 module_i2c_driver(bd6107_driver);
198
199 MODULE_DESCRIPTION("Rohm BD6107 Backlight Driver");
200 MODULE_AUTHOR("Laurent Pinchart <laurent.pinchart@ideasonboard.com>");
201 MODULE_LICENSE("GPL");
202