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);
31
32static void hp680bl_send_intensity(struct backlight_device *bd)
33{
34 unsigned long flags;
35 u16 v;
36 int intensity = bd->props.brightness;
37
38 if (bd->props.power != FB_BLANK_UNBLANK)
39 intensity = 0;
40 if (bd->props.fb_blank != FB_BLANK_UNBLANK)
41 intensity = 0;
42 if (hp680bl_suspended)
43 intensity = 0;
44
45 spin_lock_irqsave(&bl_lock, flags);
46 if (intensity && current_intensity == 0) {
47 sh_dac_enable(DAC_LCD_BRIGHTNESS);
48 v = inw(HD64461_GPBDR);
49 v &= ~HD64461_GPBDR_LCDOFF;
50 outw(v, HD64461_GPBDR);
51 sh_dac_output(255-(u8)intensity, DAC_LCD_BRIGHTNESS);
52 } else if (intensity == 0 && current_intensity != 0) {
53 sh_dac_output(255-(u8)intensity, DAC_LCD_BRIGHTNESS);
54 sh_dac_disable(DAC_LCD_BRIGHTNESS);
55 v = inw(HD64461_GPBDR);
56 v |= HD64461_GPBDR_LCDOFF;
57 outw(v, HD64461_GPBDR);
58 } else if (intensity) {
59 sh_dac_output(255-(u8)intensity, DAC_LCD_BRIGHTNESS);
60 }
61 spin_unlock_irqrestore(&bl_lock, flags);
62
63 current_intensity = intensity;
64}
65
66
67#ifdef CONFIG_PM
68static int hp680bl_suspend(struct platform_device *pdev, pm_message_t state)
69{
70 struct backlight_device *bd = platform_get_drvdata(pdev);
71
72 hp680bl_suspended = 1;
73 hp680bl_send_intensity(bd);
74 return 0;
75}
76
77static int hp680bl_resume(struct platform_device *pdev)
78{
79 struct backlight_device *bd = platform_get_drvdata(pdev);
80
81 hp680bl_suspended = 0;
82 hp680bl_send_intensity(bd);
83 return 0;
84}
85#else
86#define hp680bl_suspend NULL
87#define hp680bl_resume NULL
88#endif
89
90static int hp680bl_set_intensity(struct backlight_device *bd)
91{
92 hp680bl_send_intensity(bd);
93 return 0;
94}
95
96static int hp680bl_get_intensity(struct backlight_device *bd)
97{
98 return current_intensity;
99}
100
101static struct backlight_ops hp680bl_ops = {
102 .get_brightness = hp680bl_get_intensity,
103 .update_status = hp680bl_set_intensity,
104};
105
106static int __init hp680bl_probe(struct platform_device *pdev)
107{
108 struct backlight_device *bd;
109
110 bd = backlight_device_register ("hp680-bl", &pdev->dev, NULL,
111 &hp680bl_ops);
112 if (IS_ERR(bd))
113 return PTR_ERR(bd);
114
115 platform_set_drvdata(pdev, bd);
116
117 bd->props.max_brightness = HP680_MAX_INTENSITY;
118 bd->props.brightness = HP680_DEFAULT_INTENSITY;
119 hp680bl_send_intensity(bd);
120
121 return 0;
122}
123
124static int hp680bl_remove(struct platform_device *pdev)
125{
126 struct backlight_device *bd = platform_get_drvdata(pdev);
127
128 hp680bl_data.brightness = 0;
129 hp680bl_data.power = 0;
130 hp680bl_send_intensity(bd);
131
132 backlight_device_unregister(bd);
133
134 return 0;
135}
136
137static struct platform_driver hp680bl_driver = {
138 .probe = hp680bl_probe,
139 .remove = hp680bl_remove,
140 .suspend = hp680bl_suspend,
141 .resume = hp680bl_resume,
142 .driver = {
143 .name = "hp680-bl",
144 },
145};
146
147static struct platform_device *hp680bl_device;
148
149static int __init hp680bl_init(void)
150{
151 int ret;
152
153 ret = platform_driver_register(&hp680bl_driver);
154 if (!ret) {
155 hp680bl_device = platform_device_alloc("hp680-bl", -1);
156 if (!hp680bl_device)
157 return -ENOMEM;
158
159 ret = platform_device_add(hp680bl_device);
160
161 if (ret) {
162 platform_device_put(hp680bl_device);
163 platform_driver_unregister(&hp680bl_driver);
164 }
165 }
166 return ret;
167}
168
169static void __exit hp680bl_exit(void)
170{
171 platform_device_unregister(hp680bl_device);
172 platform_driver_unregister(&hp680bl_driver);
173}
174
175module_init(hp680bl_init);
176module_exit(hp680bl_exit);
177
178MODULE_AUTHOR("Andriy Skulysh <askulysh@gmail.com>");
179MODULE_DESCRIPTION("HP Jornada 680 Backlight Driver");
180MODULE_LICENSE("GPL");