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
32 struct tosa_bl_data {
33 struct i2c_client *i2c;
34 struct backlight_device *bl;
35
36 int comadj;
37 };
38
tosa_bl_set_backlight(struct tosa_bl_data * data,int brightness)39 static 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
tosa_bl_update_status(struct backlight_device * dev)54 static 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
tosa_bl_get_brightness(struct backlight_device * dev)69 static int tosa_bl_get_brightness(struct backlight_device *dev)
70 {
71 struct backlight_properties *props = &dev->props;
72
73 return props->brightness;
74 }
75
76 static const struct backlight_ops bl_ops = {
77 .get_brightness = tosa_bl_get_brightness,
78 .update_status = tosa_bl_update_status,
79 };
80
tosa_bl_probe(struct i2c_client * client,const struct i2c_device_id * id)81 static 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
123 err_reg:
124 data->bl = NULL;
125 return ret;
126 }
127
tosa_bl_remove(struct i2c_client * client)128 static 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
tosa_bl_suspend(struct device * dev)137 static 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
tosa_bl_resume(struct device * dev)146 static 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
155 static SIMPLE_DEV_PM_OPS(tosa_bl_pm_ops, tosa_bl_suspend, tosa_bl_resume);
156
157 static const struct i2c_device_id tosa_bl_id[] = {
158 { "tosa-bl", 0 },
159 { },
160 };
161 MODULE_DEVICE_TABLE(i2c, tosa_bl_id);
162
163 static struct i2c_driver tosa_bl_driver = {
164 .driver = {
165 .name = "tosa-bl",
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
173 module_i2c_driver(tosa_bl_driver);
174
175 MODULE_AUTHOR("Dmitry Baryshkov");
176 MODULE_LICENSE("GPL v2");
177 MODULE_DESCRIPTION("LCD/Backlight control for Sharp SL-6000 PDA");
178
179
