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
35struct lv5207lp {
36	struct i2c_client *client;
37	struct backlight_device *backlight;
38	struct lv5207lp_platform_data *pdata;
39};
40
41static int lv5207lp_write(struct lv5207lp *lv, u8 reg, u8 data)
42{
43	return i2c_smbus_write_byte_data(lv->client, reg, data);
44}
45
46static 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
65static 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->dev || lv->pdata->dev == info->device;
71}
72
73static 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
79static int lv5207lp_probe(struct i2c_client *client)
80{
81	struct lv5207lp_platform_data *pdata = dev_get_platdata(&client->dev);
82	struct backlight_device *backlight;
83	struct backlight_properties props;
84	struct lv5207lp *lv;
85
86	if (pdata == NULL) {
87		dev_err(&client->dev, "No platform data supplied\n");
88		return -EINVAL;
89	}
90
91	if (!i2c_check_functionality(client->adapter,
92				     I2C_FUNC_SMBUS_BYTE_DATA)) {
93		dev_warn(&client->dev,
94			 "I2C adapter doesn't support I2C_FUNC_SMBUS_BYTE\n");
95		return -EIO;
96	}
97
98	lv = devm_kzalloc(&client->dev, sizeof(*lv), GFP_KERNEL);
99	if (!lv)
100		return -ENOMEM;
101
102	lv->client = client;
103	lv->pdata = pdata;
104
105	memset(&props, 0, sizeof(props));
106	props.type = BACKLIGHT_RAW;
107	props.max_brightness = min_t(unsigned int, pdata->max_value,
108				     LV5207LP_MAX_BRIGHTNESS);
109	props.brightness = clamp_t(unsigned int, pdata->def_value, 0,
110				   props.max_brightness);
111
112	backlight = devm_backlight_device_register(&client->dev,
113				dev_name(&client->dev), &lv->client->dev,
114				lv, &lv5207lp_backlight_ops, &props);
115	if (IS_ERR(backlight)) {
116		dev_err(&client->dev, "failed to register backlight\n");
117		return PTR_ERR(backlight);
118	}
119
120	backlight_update_status(backlight);
121	i2c_set_clientdata(client, backlight);
122
123	return 0;
124}
125
126static void lv5207lp_remove(struct i2c_client *client)
127{
128	struct backlight_device *backlight = i2c_get_clientdata(client);
129
130	backlight->props.brightness = 0;
131	backlight_update_status(backlight);
132}
133
134static const struct i2c_device_id lv5207lp_ids[] = {
135	{ "lv5207lp", 0 },
136	{ }
137};
138MODULE_DEVICE_TABLE(i2c, lv5207lp_ids);
139
140static struct i2c_driver lv5207lp_driver = {
141	.driver = {
142		.name = "lv5207lp",
143	},
144	.probe = lv5207lp_probe,
145	.remove = lv5207lp_remove,
146	.id_table = lv5207lp_ids,
147};
148
149module_i2c_driver(lv5207lp_driver);
150
151MODULE_DESCRIPTION("Sanyo LV5207LP Backlight Driver");
152MODULE_AUTHOR("Laurent Pinchart <laurent.pinchart@ideasonboard.com>");
153MODULE_LICENSE("GPL");
154