tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * Backlight Driver for Sharp Zaurus Handhelds (various models)
3 *
4 * Copyright (c) 2004-2006 Richard Purdie
5 *
6 * Based on Sharp's 2.4 Backlight Driver
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
22static int corgibl_intensity;
23static struct backlight_properties corgibl_data;
24static struct backlight_device *corgi_backlight_device;
25static struct generic_bl_info *bl_machinfo;
26
27static unsigned long corgibl_flags;
28#define CORGIBL_SUSPENDED 0x01
29#define CORGIBL_BATTLOW 0x02
30
31static int corgibl_send_intensity(struct backlight_device *bd)
32{
33 int intensity = bd->props.brightness;
34
35 if (bd->props.power != FB_BLANK_UNBLANK)
36 intensity = 0;
37 if (bd->props.fb_blank != FB_BLANK_UNBLANK)
38 intensity = 0;
39 if (corgibl_flags & CORGIBL_SUSPENDED)
40 intensity = 0;
41 if (corgibl_flags & CORGIBL_BATTLOW)
42 intensity &= bl_machinfo->limit_mask;
43
44 bl_machinfo->set_bl_intensity(intensity);
45
46 corgibl_intensity = intensity;
47
48 if (bl_machinfo->kick_battery)
49 bl_machinfo->kick_battery();
50
51 return 0;
52}
53
54#ifdef CONFIG_PM
55static int corgibl_suspend(struct platform_device *pdev, pm_message_t state)
56{
57 struct backlight_device *bd = platform_get_drvdata(pdev);
58
59 corgibl_flags |= CORGIBL_SUSPENDED;
60 backlight_update_status(bd);
61 return 0;
62}
63
64static int corgibl_resume(struct platform_device *pdev)
65{
66 struct backlight_device *bd = platform_get_drvdata(pdev);
67
68 corgibl_flags &= ~CORGIBL_SUSPENDED;
69 backlight_update_status(bd);
70 return 0;
71}
72#else
73#define corgibl_suspend NULL
74#define corgibl_resume NULL
75#endif
76
77static int corgibl_get_intensity(struct backlight_device *bd)
78{
79 return corgibl_intensity;
80}
81
82/*
83 * Called when the battery is low to limit the backlight intensity.
84 * If limit==0 clear any limit, otherwise limit the intensity
85 */
86void corgibl_limit_intensity(int limit)
87{
88 if (limit)
89 corgibl_flags |= CORGIBL_BATTLOW;
90 else
91 corgibl_flags &= ~CORGIBL_BATTLOW;
92 backlight_update_status(corgi_backlight_device);
93}
94EXPORT_SYMBOL(corgibl_limit_intensity);
95
96
97static struct backlight_ops corgibl_ops = {
98 .get_brightness = corgibl_get_intensity,
99 .update_status = corgibl_send_intensity,
100};
101
102static int corgibl_probe(struct platform_device *pdev)
103{
104 struct generic_bl_info *machinfo = pdev->dev.platform_data;
105 const char *name = "generic-bl";
106
107 bl_machinfo = machinfo;
108 if (!machinfo->limit_mask)
109 machinfo->limit_mask = -1;
110
111 if (machinfo->name)
112 name = machinfo->name;
113
114 corgi_backlight_device = backlight_device_register (name,
115 &pdev->dev, NULL, &corgibl_ops);
116 if (IS_ERR (corgi_backlight_device))
117 return PTR_ERR (corgi_backlight_device);
118
119 platform_set_drvdata(pdev, corgi_backlight_device);
120
121 corgi_backlight_device->props.max_brightness = machinfo->max_intensity;
122 corgi_backlight_device->props.power = FB_BLANK_UNBLANK;
123 corgi_backlight_device->props.brightness = machinfo->default_intensity;
124 backlight_update_status(corgi_backlight_device);
125
126 printk("Corgi Backlight Driver Initialized.\n");
127 return 0;
128}
129
130static int corgibl_remove(struct platform_device *pdev)
131{
132 struct backlight_device *bd = platform_get_drvdata(pdev);
133
134 corgibl_data.power = 0;
135 corgibl_data.brightness = 0;
136 backlight_update_status(bd);
137
138 backlight_device_unregister(bd);
139
140 printk("Corgi Backlight Driver Unloaded\n");
141 return 0;
142}
143
144static struct platform_driver corgibl_driver = {
145 .probe = corgibl_probe,
146 .remove = corgibl_remove,
147 .suspend = corgibl_suspend,
148 .resume = corgibl_resume,
149 .driver = {
150 .name = "generic-bl",
151 },
152};
153
154static int __init corgibl_init(void)
155{
156 return platform_driver_register(&corgibl_driver);
157}
158
159static void __exit corgibl_exit(void)
160{
161 platform_driver_unregister(&corgibl_driver);
162}
163
164module_init(corgibl_init);
165module_exit(corgibl_exit);
166
167MODULE_AUTHOR("Richard Purdie <rpurdie@rpsys.net>");
168MODULE_DESCRIPTION("Corgi Backlight Driver");
169MODULE_LICENSE("GPL");