summaryrefslogtreecommitdiffstats
path: root/drivers/video/backlight/tosa_bl.c
blob: 2326fa810c5922ef1543671da152cfd13b3f4fc5 (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
/*
 *  LCD / Backlight control code for Sharp SL-6000x (tosa)
 *
 *  Copyright (c) 2005		Dirk Opfer
 *  Copyright (c) 2007,2008	Dmitry Baryshkov
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License version 2 as
 *  published by the Free Software Foundation.
 *
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/device.h>
#include <linux/spi/spi.h>
#include <linux/i2c.h>
#include <linux/gpio.h>
#include <linux/fb.h>
#include <linux/backlight.h>
#include <linux/slab.h>

#include <asm/mach/sharpsl_param.h>

#include <mach/tosa.h>

#define COMADJ_DEFAULT	97

#define DAC_CH1		0
#define DAC_CH2		1

struct tosa_bl_data {
	struct i2c_client *i2c;
	struct backlight_device *bl;

	int comadj;
};

static void tosa_bl_set_backlight(struct tosa_bl_data *data, int brightness)
{
	struct spi_device *spi = data->i2c->dev.platform_data;

	i2c_smbus_write_byte_data(data->i2c, DAC_CH1, data->comadj);

	/* SetBacklightDuty */
	i2c_smbus_write_byte_data(data->i2c, DAC_CH2, (u8)(brightness & 0xff));

	/* SetBacklightVR */
	gpio_set_value(TOSA_GPIO_BL_C20MA, brightness & 0x100);

	tosa_bl_enable(spi, brightness);
}

static int tosa_bl_update_status(struct backlight_device *dev)
{
	struct backlight_properties *props = &dev->props;
	struct tosa_bl_data *data = bl_get_data(dev);
	int power = max(props->power, props->fb_blank);
	int brightness = props->brightness;

	if (power)
		brightness = 0;

	tosa_bl_set_backlight(data, brightness);

	return 0;
}

static int tosa_bl_get_brightness(struct backlight_device *dev)
{
	struct backlight_properties *props = &dev->props;

	return props->brightness;
}

static const struct backlight_ops bl_ops = {
	.get_brightness		= tosa_bl_get_brightness,
	.update_status		= tosa_bl_update_status,
};

static int tosa_bl_probe(struct i2c_client *client,
		const struct i2c_device_id *id)
{
	struct backlight_properties props;
	struct tosa_bl_data *data;
	int ret = 0;

	data = devm_kzalloc(&client->dev, sizeof(struct tosa_bl_data),
				GFP_KERNEL);
	if (!data)
		return -ENOMEM;

	data->comadj = sharpsl_param.comadj == -1 ? COMADJ_DEFAULT : sharpsl_param.comadj;

	ret = devm_gpio_request_one(&client->dev, TOSA_GPIO_BL_C20MA,
				GPIOF_OUT_INIT_LOW, "backlight");
	if (ret) {
		dev_dbg(&data->bl->dev, "Unable to request gpio!\n");
		return ret;
	}

	i2c_set_clientdata(client, data);
	data->i2c = client;

	memset(&props, 0, sizeof(struct backlight_properties));
	props.type = BACKLIGHT_RAW;
	props.max_brightness = 512 - 1;
	data->bl = backlight_device_register("tosa-bl", &client->dev, data,
					     &bl_ops, &props);
	if (IS_ERR(data->bl)) {
		ret = PTR_ERR(data->bl);
		goto err_reg;
	}

	data->bl->props.brightness = 69;
	data->bl->props.power = FB_BLANK_UNBLANK;

	backlight_update_status(data->bl);

	return 0;

err_reg:
	data->bl = NULL;
	return ret;
}

static int tosa_bl_remove(struct i2c_client *client)
{
	struct tosa_bl_data *data = i2c_get_clientdata(client);

	backlight_device_unregister(data->bl);
	data->bl = NULL;

	return 0;
}

#ifdef CONFIG_PM
static int tosa_bl_suspend(struct i2c_client *client, pm_message_t pm)
{
	struct tosa_bl_data *data = i2c_get_clientdata(client);

	tosa_bl_set_backlight(data, 0);

	return 0;
}

static int tosa_bl_resume(struct i2c_client *client)
{
	struct tosa_bl_data *data = i2c_get_clientdata(client);

	backlight_update_status(data->bl);
	return 0;
}
#else
#define tosa_bl_suspend NULL
#define tosa_bl_resume NULL
#endif

static const struct i2c_device_id tosa_bl_id[] = {
	{ "tosa-bl", 0 },
	{ },
};

static struct i2c_driver tosa_bl_driver = {
	.driver = {
		.name		= "tosa-bl",
		.owner		= THIS_MODULE,
	},
	.probe		= tosa_bl_probe,
	.remove		= tosa_bl_remove,
	.suspend	= tosa_bl_suspend,
	.resume		= tosa_bl_resume,
	.id_table	= tosa_bl_id,
};

module_i2c_driver(tosa_bl_driver);

MODULE_AUTHOR("Dmitry Baryshkov");
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("LCD/Backlight control for Sharp SL-6000 PDA");