drivers/video/backlight/kb3886_bl.c: use usleep_range() instead of msleep() for small...
[~shefty/rdma-dev.git] / drivers / video / backlight / kb3886_bl.c
1 /*
2  *  Backlight Driver for the KB3886 Backlight
3  *
4  *  Copyright (c) 2007-2008 Claudio Nieder
5  *
6  *  Based on corgi_bl.c by Richard Purdie and kb3886 driver by Robert Woerle
7  *
8  *  This program is free software; you can redistribute it and/or modify
9  *  it under the terms of the GNU General Public License version 2 as
10  *  published by the Free Software Foundation.
11  *
12  */
13
14 #include <linux/module.h>
15 #include <linux/kernel.h>
16 #include <linux/init.h>
17 #include <linux/platform_device.h>
18 #include <linux/mutex.h>
19 #include <linux/fb.h>
20 #include <linux/backlight.h>
21 #include <linux/delay.h>
22 #include <linux/dmi.h>
23
24 #define KB3886_PARENT 0x64
25 #define KB3886_IO 0x60
26 #define KB3886_ADC_DAC_PWM 0xC4
27 #define KB3886_PWM0_WRITE 0x81
28 #define KB3886_PWM0_READ 0x41
29
30 static DEFINE_MUTEX(bl_mutex);
31
32 static void kb3886_bl_set_intensity(int intensity)
33 {
34         mutex_lock(&bl_mutex);
35         intensity = intensity&0xff;
36         outb(KB3886_ADC_DAC_PWM, KB3886_PARENT);
37         usleep_range(10000, 11000);
38         outb(KB3886_PWM0_WRITE, KB3886_IO);
39         usleep_range(10000, 11000);
40         outb(intensity, KB3886_IO);
41         mutex_unlock(&bl_mutex);
42 }
43
44 struct kb3886bl_machinfo {
45         int max_intensity;
46         int default_intensity;
47         int limit_mask;
48         void (*set_bl_intensity)(int intensity);
49 };
50
51 static struct kb3886bl_machinfo kb3886_bl_machinfo = {
52         .max_intensity = 0xff,
53         .default_intensity = 0xa0,
54         .limit_mask = 0x7f,
55         .set_bl_intensity = kb3886_bl_set_intensity,
56 };
57
58 static struct platform_device kb3886bl_device = {
59         .name           = "kb3886-bl",
60         .dev            = {
61                 .platform_data  = &kb3886_bl_machinfo,
62         },
63         .id             = -1,
64 };
65
66 static struct platform_device *devices[] __initdata = {
67         &kb3886bl_device,
68 };
69
70 /*
71  * Back to driver
72  */
73
74 static int kb3886bl_intensity;
75 static struct backlight_device *kb3886_backlight_device;
76 static struct kb3886bl_machinfo *bl_machinfo;
77
78 static unsigned long kb3886bl_flags;
79 #define KB3886BL_SUSPENDED     0x01
80
81 static struct dmi_system_id __initdata kb3886bl_device_table[] = {
82         {
83                 .ident = "Sahara Touch-iT",
84                 .matches = {
85                         DMI_MATCH(DMI_SYS_VENDOR, "SDV"),
86                         DMI_MATCH(DMI_PRODUCT_NAME, "iTouch T201"),
87                 },
88         },
89         { }
90 };
91
92 static int kb3886bl_send_intensity(struct backlight_device *bd)
93 {
94         int intensity = bd->props.brightness;
95
96         if (bd->props.power != FB_BLANK_UNBLANK)
97                 intensity = 0;
98         if (bd->props.fb_blank != FB_BLANK_UNBLANK)
99                 intensity = 0;
100         if (kb3886bl_flags & KB3886BL_SUSPENDED)
101                 intensity = 0;
102
103         bl_machinfo->set_bl_intensity(intensity);
104
105         kb3886bl_intensity = intensity;
106         return 0;
107 }
108
109 #ifdef CONFIG_PM
110 static int kb3886bl_suspend(struct platform_device *pdev, pm_message_t state)
111 {
112         struct backlight_device *bd = platform_get_drvdata(pdev);
113
114         kb3886bl_flags |= KB3886BL_SUSPENDED;
115         backlight_update_status(bd);
116         return 0;
117 }
118
119 static int kb3886bl_resume(struct platform_device *pdev)
120 {
121         struct backlight_device *bd = platform_get_drvdata(pdev);
122
123         kb3886bl_flags &= ~KB3886BL_SUSPENDED;
124         backlight_update_status(bd);
125         return 0;
126 }
127 #else
128 #define kb3886bl_suspend        NULL
129 #define kb3886bl_resume         NULL
130 #endif
131
132 static int kb3886bl_get_intensity(struct backlight_device *bd)
133 {
134         return kb3886bl_intensity;
135 }
136
137 static const struct backlight_ops kb3886bl_ops = {
138         .get_brightness = kb3886bl_get_intensity,
139         .update_status  = kb3886bl_send_intensity,
140 };
141
142 static int kb3886bl_probe(struct platform_device *pdev)
143 {
144         struct backlight_properties props;
145         struct kb3886bl_machinfo *machinfo = pdev->dev.platform_data;
146
147         bl_machinfo = machinfo;
148         if (!machinfo->limit_mask)
149                 machinfo->limit_mask = -1;
150
151         memset(&props, 0, sizeof(struct backlight_properties));
152         props.type = BACKLIGHT_RAW;
153         props.max_brightness = machinfo->max_intensity;
154         kb3886_backlight_device = backlight_device_register("kb3886-bl",
155                                                             &pdev->dev, NULL,
156                                                             &kb3886bl_ops,
157                                                             &props);
158         if (IS_ERR(kb3886_backlight_device))
159                 return PTR_ERR(kb3886_backlight_device);
160
161         platform_set_drvdata(pdev, kb3886_backlight_device);
162
163         kb3886_backlight_device->props.power = FB_BLANK_UNBLANK;
164         kb3886_backlight_device->props.brightness = machinfo->default_intensity;
165         backlight_update_status(kb3886_backlight_device);
166
167         return 0;
168 }
169
170 static int kb3886bl_remove(struct platform_device *pdev)
171 {
172         struct backlight_device *bd = platform_get_drvdata(pdev);
173
174         backlight_device_unregister(bd);
175
176         return 0;
177 }
178
179 static struct platform_driver kb3886bl_driver = {
180         .probe          = kb3886bl_probe,
181         .remove         = kb3886bl_remove,
182         .suspend        = kb3886bl_suspend,
183         .resume         = kb3886bl_resume,
184         .driver         = {
185                 .name   = "kb3886-bl",
186         },
187 };
188
189 static int __init kb3886_init(void)
190 {
191         if (!dmi_check_system(kb3886bl_device_table))
192                 return -ENODEV;
193
194         platform_add_devices(devices, ARRAY_SIZE(devices));
195         return platform_driver_register(&kb3886bl_driver);
196 }
197
198 static void __exit kb3886_exit(void)
199 {
200         platform_driver_unregister(&kb3886bl_driver);
201 }
202
203 module_init(kb3886_init);
204 module_exit(kb3886_exit);
205
206 MODULE_AUTHOR("Claudio Nieder <private@claudio.ch>");
207 MODULE_DESCRIPTION("Tabletkiosk Sahara Touch-iT Backlight Driver");
208 MODULE_LICENSE("GPL");
209 MODULE_ALIAS("dmi:*:svnSDV:pniTouchT201:*");