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