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 HP Jornada 680
3 *
4 * Copyright (c) 2005 Andriy Skulysh
5 *
6 * Based on Sharp's Corgi Backlight Driver
7 *
8 * This file is subject to the terms and conditions of the GNU General Public
9 * License. See the file "COPYING" in the main directory of this archive
10 * for more details.
11 */
12
13#include <linux/module.h>
14#include <linux/kernel.h>
15#include <linux/init.h>
16#include <linux/platform_device.h>
17#include <linux/spinlock.h>
18#include <linux/fb.h>
19#include <linux/backlight.h>
20
21#include <asm/cpu/dac.h>
22#include <asm/hp6xx.h>
23#include <asm/hd64461.h>
24
25#define HP680_MAX_INTENSITY 255
26#define HP680_DEFAULT_INTENSITY 10
27
28static int hp680bl_suspended;
29static int current_intensity = 0;
30static DEFINE_SPINLOCK(bl_lock);
31static struct backlight_device *hp680_backlight_device;
32
33static void hp680bl_send_intensity(struct backlight_device *bd)
34{
35 unsigned long flags;
36 u16 v;
37 int intensity = bd->props->brightness;
38
39 if (bd->props->power != FB_BLANK_UNBLANK)
40 intensity = 0;
41 if (bd->props->fb_blank != FB_BLANK_UNBLANK)
42 intensity = 0;
43 if (hp680bl_suspended)
44 intensity = 0;
45
46 spin_lock_irqsave(&bl_lock, flags);
47 if (intensity && current_intensity == 0) {
48 sh_dac_enable(DAC_LCD_BRIGHTNESS);
49 v = inw(HD64461_GPBDR);
50 v &= ~HD64461_GPBDR_LCDOFF;
51 outw(v, HD64461_GPBDR);
52 sh_dac_output(255-(u8)intensity, DAC_LCD_BRIGHTNESS);
53 } else if (intensity == 0 && current_intensity != 0) {
54 sh_dac_output(255-(u8)intensity, DAC_LCD_BRIGHTNESS);
55 sh_dac_disable(DAC_LCD_BRIGHTNESS);
56 v = inw(HD64461_GPBDR);
57 v |= HD64461_GPBDR_LCDOFF;
58 outw(v, HD64461_GPBDR);
59 } else if (intensity) {
60 sh_dac_output(255-(u8)intensity, DAC_LCD_BRIGHTNESS);
61 }
62 spin_unlock_irqrestore(&bl_lock, flags);
63
64 current_intensity = intensity;
65}
66
67
68#ifdef CONFIG_PM
69static int hp680bl_suspend(struct platform_device *dev, pm_message_t state)
70{
71 hp680bl_suspended = 1;
72 hp680bl_send_intensity(hp680_backlight_device);
73 return 0;
74}
75
76static int hp680bl_resume(struct platform_device *dev)
77{
78 hp680bl_suspended = 0;
79 hp680bl_send_intensity(hp680_backlight_device);
80 return 0;
81}
82#else
83#define hp680bl_suspend NULL
84#define hp680bl_resume NULL
85#endif
86
87static int hp680bl_set_intensity(struct backlight_device *bd)
88{
89 hp680bl_send_intensity(bd);
90 return 0;
91}
92
93static int hp680bl_get_intensity(struct backlight_device *bd)
94{
95 return current_intensity;
96}
97
98static struct backlight_properties hp680bl_data = {
99 .owner = THIS_MODULE,
100 .max_brightness = HP680_MAX_INTENSITY,
101 .get_brightness = hp680bl_get_intensity,
102 .update_status = hp680bl_set_intensity,
103};
104
105static int __init hp680bl_probe(struct platform_device *dev)
106{
107 hp680_backlight_device = backlight_device_register ("hp680-bl",
108 NULL, &hp680bl_data);
109 if (IS_ERR (hp680_backlight_device))
110 return PTR_ERR (hp680_backlight_device);
111
112 hp680_backlight_device->props->brightness = HP680_DEFAULT_INTENSITY;
113 hp680bl_send_intensity(hp680_backlight_device);
114
115 return 0;
116}
117
118static int hp680bl_remove(struct platform_device *dev)
119{
120 hp680bl_data.brightness = 0;
121 hp680bl_data.power = 0;
122 hp680bl_send_intensity(hp680_backlight_device);
123
124 backlight_device_unregister(hp680_backlight_device);
125
126 return 0;
127}
128
129static struct platform_driver hp680bl_driver = {
130 .probe = hp680bl_probe,
131 .remove = hp680bl_remove,
132 .suspend = hp680bl_suspend,
133 .resume = hp680bl_resume,
134 .driver = {
135 .name = "hp680-bl",
136 },
137};
138
139static struct platform_device *hp680bl_device;
140
141static int __init hp680bl_init(void)
142{
143 int ret;
144
145 ret = platform_driver_register(&hp680bl_driver);
146 if (!ret) {
147 hp680bl_device = platform_device_alloc("hp680-bl", -1);
148 if (!hp680bl_device)
149 return -ENOMEM;
150
151 ret = platform_device_add(hp680bl_device);
152
153 if (ret) {
154 platform_device_put(hp680bl_device);
155 platform_driver_unregister(&hp680bl_driver);
156 }
157 }
158 return ret;
159}
160
161static void __exit hp680bl_exit(void)
162{
163 platform_device_unregister(hp680bl_device);
164 platform_driver_unregister(&hp680bl_driver);
165}
166
167module_init(hp680bl_init);
168module_exit(hp680bl_exit);
169
170MODULE_AUTHOR("Andriy Skulysh <askulysh@gmail.com>");
171MODULE_DESCRIPTION("HP Jornada 680 Backlight Driver");
172MODULE_LICENSE("GPL");