1/*
2 *  LCD / Backlight control code for Sharp SL-6000x (tosa)
3 *
4 *  Copyright (c) 2005		Dirk Opfer
5 *  Copyright (c) 2007,2008	Dmitry Baryshkov
6 *
7 *  This program is free software; you can redistribute it and/or modify
8 *  it under the terms of the GNU General Public License version 2 as
9 *  published by the Free Software Foundation.
10 *
11 */
12
13#include <linux/kernel.h>
14#include <linux/module.h>
15#include <linux/device.h>
16#include <linux/spi/spi.h>
17#include <linux/i2c.h>
18#include <linux/gpio.h>
19#include <linux/fb.h>
20#include <linux/backlight.h>
21#include <linux/slab.h>
22
23#include <asm/mach/sharpsl_param.h>
24
25#include <mach/tosa.h>
26
27#define COMADJ_DEFAULT	97
28
29#define DAC_CH1		0
30#define DAC_CH2		1
31
32struct tosa_bl_data {
33	struct i2c_client *i2c;
34	struct backlight_device *bl;
35
36	int comadj;
37};
38
39static void tosa_bl_set_backlight(struct tosa_bl_data *data, int brightness)
40{
41	struct spi_device *spi = dev_get_platdata(&data->i2c->dev);
42
43	i2c_smbus_write_byte_data(data->i2c, DAC_CH1, data->comadj);
44
45	/* SetBacklightDuty */
46	i2c_smbus_write_byte_data(data->i2c, DAC_CH2, (u8)(brightness & 0xff));
47
48	/* SetBacklightVR */
49	gpio_set_value(TOSA_GPIO_BL_C20MA, brightness & 0x100);
50
51	tosa_bl_enable(spi, brightness);
52}
53
54static int tosa_bl_update_status(struct backlight_device *dev)
55{
56	struct backlight_properties *props = &dev->props;
57	struct tosa_bl_data *data = bl_get_data(dev);
58	int power = max(props->power, props->fb_blank);
59	int brightness = props->brightness;
60
61	if (power)
62		brightness = 0;
63
64	tosa_bl_set_backlight(data, brightness);
65
66	return 0;
67}
68
69static int tosa_bl_get_brightness(struct backlight_device *dev)
70{
71	struct backlight_properties *props = &dev->props;
72
73	return props->brightness;
74}
75
76static const struct backlight_ops bl_ops = {
77	.get_brightness		= tosa_bl_get_brightness,
78	.update_status		= tosa_bl_update_status,
79};
80
81static int tosa_bl_probe(struct i2c_client *client,
82		const struct i2c_device_id *id)
83{
84	struct backlight_properties props;
85	struct tosa_bl_data *data;
86	int ret = 0;
87
88	data = devm_kzalloc(&client->dev, sizeof(struct tosa_bl_data),
89				GFP_KERNEL);
90	if (!data)
91		return -ENOMEM;
92
93	data->comadj = sharpsl_param.comadj == -1 ? COMADJ_DEFAULT : sharpsl_param.comadj;
94
95	ret = devm_gpio_request_one(&client->dev, TOSA_GPIO_BL_C20MA,
96				GPIOF_OUT_INIT_LOW, "backlight");
97	if (ret) {
98		dev_dbg(&data->bl->dev, "Unable to request gpio!\n");
99		return ret;
100	}
101
102	i2c_set_clientdata(client, data);
103	data->i2c = client;
104
105	memset(&props, 0, sizeof(struct backlight_properties));
106	props.type = BACKLIGHT_RAW;
107	props.max_brightness = 512 - 1;
108	data->bl = devm_backlight_device_register(&client->dev, "tosa-bl",
109						&client->dev, data, &bl_ops,
110						&props);
111	if (IS_ERR(data->bl)) {
112		ret = PTR_ERR(data->bl);
113		goto err_reg;
114	}
115
116	data->bl->props.brightness = 69;
117	data->bl->props.power = FB_BLANK_UNBLANK;
118
119	backlight_update_status(data->bl);
120
121	return 0;
122
123err_reg:
124	data->bl = NULL;
125	return ret;
126}
127
128static int tosa_bl_remove(struct i2c_client *client)
129{
130	struct tosa_bl_data *data = i2c_get_clientdata(client);
131
132	data->bl = NULL;
133	return 0;
134}
135
136#ifdef CONFIG_PM_SLEEP
137static int tosa_bl_suspend(struct device *dev)
138{
139	struct tosa_bl_data *data = dev_get_drvdata(dev);
140
141	tosa_bl_set_backlight(data, 0);
142
143	return 0;
144}
145
146static int tosa_bl_resume(struct device *dev)
147{
148	struct tosa_bl_data *data = dev_get_drvdata(dev);
149
150	backlight_update_status(data->bl);
151	return 0;
152}
153#endif
154
155static SIMPLE_DEV_PM_OPS(tosa_bl_pm_ops, tosa_bl_suspend, tosa_bl_resume);
156
157static const struct i2c_device_id tosa_bl_id[] = {
158	{ "tosa-bl", 0 },
159	{ },
160};
161
162static struct i2c_driver tosa_bl_driver = {
163	.driver = {
164		.name		= "tosa-bl",
165		.owner		= THIS_MODULE,
166		.pm		= &tosa_bl_pm_ops,
167	},
168	.probe		= tosa_bl_probe,
169	.remove		= tosa_bl_remove,
170	.id_table	= tosa_bl_id,
171};
172
173module_i2c_driver(tosa_bl_driver);
174
175MODULE_AUTHOR("Dmitry Baryshkov");
176MODULE_LICENSE("GPL v2");
177MODULE_DESCRIPTION("LCD/Backlight control for Sharp SL-6000 PDA");
178
179