summaryrefslogtreecommitdiffstats
path: root/kernel/drivers/video/backlight/da9052_bl.c
blob: b1943e7735a12881130dc3d94b4266a992fc4230 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
/*
 * Backlight Driver for Dialog DA9052 PMICs
 *
 * Copyright(c) 2012 Dialog Semiconductor Ltd.
 *
 * Author: David Dajun Chen <dchen@diasemi.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 */

#include <linux/backlight.h>
#include <linux/delay.h>
#include <linux/fb.h>
#include <linux/module.h>
#include <linux/platform_device.h>

#include <linux/mfd/da9052/da9052.h>
#include <linux/mfd/da9052/reg.h>

#define DA9052_MAX_BRIGHTNESS		0xFF

enum {
	DA9052_WLEDS_OFF,
	DA9052_WLEDS_ON,
};

enum {
	DA9052_TYPE_WLED1,
	DA9052_TYPE_WLED2,
	DA9052_TYPE_WLED3,
};

static const unsigned char wled_bank[] = {
	DA9052_LED1_CONF_REG,
	DA9052_LED2_CONF_REG,
	DA9052_LED3_CONF_REG,
};

struct da9052_bl {
	struct da9052 *da9052;
	uint brightness;
	uint state;
	uint led_reg;
};

static int da9052_adjust_wled_brightness(struct da9052_bl *wleds)
{
	unsigned char boost_en;
	unsigned char i_sink;
	int ret;

	boost_en = 0x3F;
	i_sink = 0xFF;
	if (wleds->state == DA9052_WLEDS_OFF) {
		boost_en = 0x00;
		i_sink = 0x00;
	}

	ret = da9052_reg_write(wleds->da9052, DA9052_BOOST_REG, boost_en);
	if (ret < 0)
		return ret;

	ret = da9052_reg_write(wleds->da9052, DA9052_LED_CONT_REG, i_sink);
	if (ret < 0)
		return ret;

	ret = da9052_reg_write(wleds->da9052, wled_bank[wleds->led_reg], 0x0);
	if (ret < 0)
		return ret;

	usleep_range(10000, 11000);

	if (wleds->brightness) {
		ret = da9052_reg_write(wleds->da9052, wled_bank[wleds->led_reg],
				       wleds->brightness);
		if (ret < 0)
			return ret;
	}

	return 0;
}

static int da9052_backlight_update_status(struct backlight_device *bl)
{
	int brightness = bl->props.brightness;
	struct da9052_bl *wleds = bl_get_data(bl);

	wleds->brightness = brightness;
	wleds->state = DA9052_WLEDS_ON;

	return da9052_adjust_wled_brightness(wleds);
}

static int da9052_backlight_get_brightness(struct backlight_device *bl)
{
	struct da9052_bl *wleds = bl_get_data(bl);

	return wleds->brightness;
}

static const struct backlight_ops da9052_backlight_ops = {
	.update_status = da9052_backlight_update_status,
	.get_brightness = da9052_backlight_get_brightness,
};

static int da9052_backlight_probe(struct platform_device *pdev)
{
	struct backlight_device *bl;
	struct backlight_properties props;
	struct da9052_bl *wleds;

	wleds = devm_kzalloc(&pdev->dev, sizeof(struct da9052_bl), GFP_KERNEL);
	if (!wleds)
		return -ENOMEM;

	wleds->da9052 = dev_get_drvdata(pdev->dev.parent);
	wleds->brightness = 0;
	wleds->led_reg = platform_get_device_id(pdev)->driver_data;
	wleds->state = DA9052_WLEDS_OFF;

	props.type = BACKLIGHT_RAW;
	props.max_brightness = DA9052_MAX_BRIGHTNESS;

	bl = devm_backlight_device_register(&pdev->dev, pdev->name,
					wleds->da9052->dev, wleds,
					&da9052_backlight_ops, &props);
	if (IS_ERR(bl)) {
		dev_err(&pdev->dev, "Failed to register backlight\n");
		return PTR_ERR(bl);
	}

	bl->props.max_brightness = DA9052_MAX_BRIGHTNESS;
	bl->props.brightness = 0;
	platform_set_drvdata(pdev, bl);

	return da9052_adjust_wled_brightness(wleds);
}

static int da9052_backlight_remove(struct platform_device *pdev)
{
	struct backlight_device *bl = platform_get_drvdata(pdev);
	struct da9052_bl *wleds = bl_get_data(bl);

	wleds->brightness = 0;
	wleds->state = DA9052_WLEDS_OFF;
	da9052_adjust_wled_brightness(wleds);

	return 0;
}

static struct platform_device_id da9052_wled_ids[] = {
	{
		.name		= "da9052-wled1",
		.driver_data	= DA9052_TYPE_WLED1,
	},
	{
		.name		= "da9052-wled2",
		.driver_data	= DA9052_TYPE_WLED2,
	},
	{
		.name		= "da9052-wled3",
		.driver_data	= DA9052_TYPE_WLED3,
	},
	{ },
};

static struct platform_driver da9052_wled_driver = {
	.probe		= da9052_backlight_probe,
	.remove		= da9052_backlight_remove,
	.id_table	= da9052_wled_ids,
	.driver	= {
		.name	= "da9052-wled",
	},
};

module_platform_driver(da9052_wled_driver);

MODULE_AUTHOR("David Dajun Chen <dchen@diasemi.com>");
MODULE_DESCRIPTION("Backlight driver for DA9052 PMIC");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:da9052-backlight");