tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
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
22#include <asm/mach/sharpsl_param.h>
23
24#include <mach/tosa.h>
25
26#define COMADJ_DEFAULT 97
27
28#define DAC_CH1 0
29#define DAC_CH2 1
30
31struct tosa_bl_data {
32 struct i2c_client *i2c;
33 struct backlight_device *bl;
34
35 int comadj;
36};
37
38static void tosa_bl_set_backlight(struct tosa_bl_data *data, int brightness)
39{
40 struct spi_device *spi = data->i2c->dev.platform_data;
41
42 i2c_smbus_write_byte_data(data->i2c, DAC_CH1, data->comadj);
43
44 /* SetBacklightDuty */
45 i2c_smbus_write_byte_data(data->i2c, DAC_CH2, (u8)(brightness & 0xff));
46
47 /* SetBacklightVR */
48 gpio_set_value(TOSA_GPIO_BL_C20MA, brightness & 0x100);
49
50 tosa_bl_enable(spi, brightness);
51}
52
53static int tosa_bl_update_status(struct backlight_device *dev)
54{
55 struct backlight_properties *props = &dev->props;
56 struct tosa_bl_data *data = dev_get_drvdata(&dev->dev);
57 int power = max(props->power, props->fb_blank);
58 int brightness = props->brightness;
59
60 if (power)
61 brightness = 0;
62
63 tosa_bl_set_backlight(data, brightness);
64
65 return 0;
66}
67
68static int tosa_bl_get_brightness(struct backlight_device *dev)
69{
70 struct backlight_properties *props = &dev->props;
71
72 return props->brightness;
73}
74
75static struct backlight_ops bl_ops = {
76 .get_brightness = tosa_bl_get_brightness,
77 .update_status = tosa_bl_update_status,
78};
79
80static int __devinit tosa_bl_probe(struct i2c_client *client,
81 const struct i2c_device_id *id)
82{
83 struct tosa_bl_data *data = kzalloc(sizeof(struct tosa_bl_data), GFP_KERNEL);
84 int ret = 0;
85 if (!data)
86 return -ENOMEM;
87
88 data->comadj = sharpsl_param.comadj == -1 ? COMADJ_DEFAULT : sharpsl_param.comadj;
89
90 ret = gpio_request(TOSA_GPIO_BL_C20MA, "backlight");
91 if (ret) {
92 dev_dbg(&data->bl->dev, "Unable to request gpio!\n");
93 goto err_gpio_bl;
94 }
95 ret = gpio_direction_output(TOSA_GPIO_BL_C20MA, 0);
96 if (ret)
97 goto err_gpio_dir;
98
99 i2c_set_clientdata(client, data);
100 data->i2c = client;
101
102 data->bl = backlight_device_register("tosa-bl", &client->dev,
103 data, &bl_ops);
104 if (IS_ERR(data->bl)) {
105 ret = PTR_ERR(data->bl);
106 goto err_reg;
107 }
108
109 data->bl->props.brightness = 69;
110 data->bl->props.max_brightness = 512 - 1;
111 data->bl->props.power = FB_BLANK_UNBLANK;
112
113 backlight_update_status(data->bl);
114
115 return 0;
116
117err_reg:
118 data->bl = NULL;
119 i2c_set_clientdata(client, NULL);
120err_gpio_dir:
121 gpio_free(TOSA_GPIO_BL_C20MA);
122err_gpio_bl:
123 kfree(data);
124 return ret;
125}
126
127static int __devexit tosa_bl_remove(struct i2c_client *client)
128{
129 struct tosa_bl_data *data = i2c_get_clientdata(client);
130
131 backlight_device_unregister(data->bl);
132 data->bl = NULL;
133 i2c_set_clientdata(client, NULL);
134
135 gpio_free(TOSA_GPIO_BL_C20MA);
136
137 kfree(data);
138
139 return 0;
140}
141
142#ifdef CONFIG_PM
143static int tosa_bl_suspend(struct i2c_client *client, pm_message_t pm)
144{
145 struct tosa_bl_data *data = i2c_get_clientdata(client);
146
147 tosa_bl_set_backlight(data, 0);
148
149 return 0;
150}
151
152static int tosa_bl_resume(struct i2c_client *client)
153{
154 struct tosa_bl_data *data = i2c_get_clientdata(client);
155
156 backlight_update_status(data->bl);
157 return 0;
158}
159#else
160#define tosa_bl_suspend NULL
161#define tosa_bl_resume NULL
162#endif
163
164static const struct i2c_device_id tosa_bl_id[] = {
165 { "tosa-bl", 0 },
166 { },
167};
168
169
170static struct i2c_driver tosa_bl_driver = {
171 .driver = {
172 .name = "tosa-bl",
173 .owner = THIS_MODULE,
174 },
175 .probe = tosa_bl_probe,
176 .remove = __devexit_p(tosa_bl_remove),
177 .suspend = tosa_bl_suspend,
178 .resume = tosa_bl_resume,
179 .id_table = tosa_bl_id,
180};
181
182static int __init tosa_bl_init(void)
183{
184 return i2c_add_driver(&tosa_bl_driver);
185}
186
187static void __exit tosa_bl_exit(void)
188{
189 i2c_del_driver(&tosa_bl_driver);
190}
191
192module_init(tosa_bl_init);
193module_exit(tosa_bl_exit);
194
195MODULE_AUTHOR("Dmitry Baryshkov");
196MODULE_LICENSE("GPL v2");
197MODULE_DESCRIPTION("LCD/Backlight control for Sharp SL-6000 PDA");
198