tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
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/i2c.h>
13#include <linux/module.h>
14#include <linux/platform_data/lv5207lp.h>
15#include <linux/slab.h>
16
17#define LV5207LP_CTRL1 0x00
18#define LV5207LP_CPSW (1 << 7)
19#define LV5207LP_SCTEN (1 << 6)
20#define LV5207LP_C10 (1 << 5)
21#define LV5207LP_CKSW (1 << 4)
22#define LV5207LP_RSW (1 << 3)
23#define LV5207LP_GSW (1 << 2)
24#define LV5207LP_BSW (1 << 1)
25#define LV5207LP_CTRL2 0x01
26#define LV5207LP_MSW (1 << 7)
27#define LV5207LP_MLED4 (1 << 6)
28#define LV5207LP_RED 0x02
29#define LV5207LP_GREEN 0x03
30#define LV5207LP_BLUE 0x04
31
32#define LV5207LP_MAX_BRIGHTNESS 32
33
34struct lv5207lp {
35 struct i2c_client *client;
36 struct backlight_device *backlight;
37 struct lv5207lp_platform_data *pdata;
38};
39
40static int lv5207lp_write(struct lv5207lp *lv, u8 reg, u8 data)
41{
42 return i2c_smbus_write_byte_data(lv->client, reg, data);
43}
44
45static int lv5207lp_backlight_update_status(struct backlight_device *backlight)
46{
47 struct lv5207lp *lv = bl_get_data(backlight);
48 int brightness = backlight_get_brightness(backlight);
49
50 if (brightness) {
51 lv5207lp_write(lv, LV5207LP_CTRL1,
52 LV5207LP_CPSW | LV5207LP_C10 | LV5207LP_CKSW);
53 lv5207lp_write(lv, LV5207LP_CTRL2,
54 LV5207LP_MSW | LV5207LP_MLED4 |
55 (brightness - 1));
56 } else {
57 lv5207lp_write(lv, LV5207LP_CTRL1, 0);
58 lv5207lp_write(lv, LV5207LP_CTRL2, 0);
59 }
60
61 return 0;
62}
63
64static bool lv5207lp_backlight_controls_device(struct backlight_device *backlight,
65 struct device *display_dev)
66{
67 struct lv5207lp *lv = bl_get_data(backlight);
68
69 return !lv->pdata->dev || lv->pdata->dev == display_dev;
70}
71
72static const struct backlight_ops lv5207lp_backlight_ops = {
73 .options = BL_CORE_SUSPENDRESUME,
74 .update_status = lv5207lp_backlight_update_status,
75 .controls_device = lv5207lp_backlight_controls_device,
76};
77
78static int lv5207lp_probe(struct i2c_client *client)
79{
80 struct lv5207lp_platform_data *pdata = dev_get_platdata(&client->dev);
81 struct backlight_device *backlight;
82 struct backlight_properties props;
83 struct lv5207lp *lv;
84
85 if (pdata == NULL) {
86 dev_err(&client->dev, "No platform data supplied\n");
87 return -EINVAL;
88 }
89
90 if (!i2c_check_functionality(client->adapter,
91 I2C_FUNC_SMBUS_BYTE_DATA)) {
92 dev_warn(&client->dev,
93 "I2C adapter doesn't support I2C_FUNC_SMBUS_BYTE\n");
94 return -EIO;
95 }
96
97 lv = devm_kzalloc(&client->dev, sizeof(*lv), GFP_KERNEL);
98 if (!lv)
99 return -ENOMEM;
100
101 lv->client = client;
102 lv->pdata = pdata;
103
104 memset(&props, 0, sizeof(props));
105 props.type = BACKLIGHT_RAW;
106 props.max_brightness = min_t(unsigned int, pdata->max_value,
107 LV5207LP_MAX_BRIGHTNESS);
108 props.brightness = clamp_t(unsigned int, pdata->def_value, 0,
109 props.max_brightness);
110
111 backlight = devm_backlight_device_register(&client->dev,
112 dev_name(&client->dev), &lv->client->dev,
113 lv, &lv5207lp_backlight_ops, &props);
114 if (IS_ERR(backlight)) {
115 dev_err(&client->dev, "failed to register backlight\n");
116 return PTR_ERR(backlight);
117 }
118
119 backlight_update_status(backlight);
120 i2c_set_clientdata(client, backlight);
121
122 return 0;
123}
124
125static void lv5207lp_remove(struct i2c_client *client)
126{
127 struct backlight_device *backlight = i2c_get_clientdata(client);
128
129 backlight->props.brightness = 0;
130 backlight_update_status(backlight);
131}
132
133static const struct i2c_device_id lv5207lp_ids[] = {
134 { "lv5207lp" },
135 { }
136};
137MODULE_DEVICE_TABLE(i2c, lv5207lp_ids);
138
139static struct i2c_driver lv5207lp_driver = {
140 .driver = {
141 .name = "lv5207lp",
142 },
143 .probe = lv5207lp_probe,
144 .remove = lv5207lp_remove,
145 .id_table = lv5207lp_ids,
146};
147
148module_i2c_driver(lv5207lp_driver);
149
150MODULE_DESCRIPTION("Sanyo LV5207LP Backlight Driver");
151MODULE_AUTHOR("Laurent Pinchart <laurent.pinchart@ideasonboard.com>");
152MODULE_LICENSE("GPL");