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 <cpu/dac.h>
22#include <mach/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;
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 = backlight_get_brightness(bd);
37
38 if (hp680bl_suspended)
39 intensity = 0;
40
41 spin_lock_irqsave(&bl_lock, flags);
42 if (intensity && current_intensity == 0) {
43 sh_dac_enable(DAC_LCD_BRIGHTNESS);
44 v = inw(port: HD64461_GPBDR);
45 v &= ~HD64461_GPBDR_LCDOFF;
46 outw(value: v, port: HD64461_GPBDR);
47 sh_dac_output(255-(u8)intensity, DAC_LCD_BRIGHTNESS);
48 } else if (intensity == 0 && current_intensity != 0) {
49 sh_dac_output(255-(u8)intensity, DAC_LCD_BRIGHTNESS);
50 sh_dac_disable(DAC_LCD_BRIGHTNESS);
51 v = inw(port: HD64461_GPBDR);
52 v |= HD64461_GPBDR_LCDOFF;
53 outw(value: v, port: HD64461_GPBDR);
54 } else if (intensity) {
55 sh_dac_output(255-(u8)intensity, DAC_LCD_BRIGHTNESS);
56 }
57 spin_unlock_irqrestore(lock: &bl_lock, flags);
58
59 current_intensity = intensity;
60}
61
62
63#ifdef CONFIG_PM_SLEEP
64static int hp680bl_suspend(struct device *dev)
65{
66 struct backlight_device *bd = dev_get_drvdata(dev);
67
68 hp680bl_suspended = 1;
69 hp680bl_send_intensity(bd);
70 return 0;
71}
72
73static int hp680bl_resume(struct device *dev)
74{
75 struct backlight_device *bd = dev_get_drvdata(dev);
76
77 hp680bl_suspended = 0;
78 hp680bl_send_intensity(bd);
79 return 0;
80}
81#endif
82
83static SIMPLE_DEV_PM_OPS(hp680bl_pm_ops, hp680bl_suspend, hp680bl_resume);
84
85static int hp680bl_set_intensity(struct backlight_device *bd)
86{
87 hp680bl_send_intensity(bd);
88 return 0;
89}
90
91static int hp680bl_get_intensity(struct backlight_device *bd)
92{
93 return current_intensity;
94}
95
96static const struct backlight_ops hp680bl_ops = {
97 .get_brightness = hp680bl_get_intensity,
98 .update_status = hp680bl_set_intensity,
99};
100
101static int hp680bl_probe(struct platform_device *pdev)
102{
103 struct backlight_properties props;
104 struct backlight_device *bd;
105
106 memset(&props, 0, sizeof(struct backlight_properties));
107 props.type = BACKLIGHT_RAW;
108 props.max_brightness = HP680_MAX_INTENSITY;
109 bd = devm_backlight_device_register(dev: &pdev->dev, name: "hp680-bl", parent: &pdev->dev,
110 NULL, ops: &hp680bl_ops, props: &props);
111 if (IS_ERR(ptr: bd))
112 return PTR_ERR(ptr: bd);
113
114 platform_set_drvdata(pdev, data: bd);
115
116 bd->props.brightness = HP680_DEFAULT_INTENSITY;
117 hp680bl_send_intensity(bd);
118
119 return 0;
120}
121
122static void hp680bl_remove(struct platform_device *pdev)
123{
124 struct backlight_device *bd = platform_get_drvdata(pdev);
125
126 bd->props.brightness = 0;
127 bd->props.power = 0;
128 hp680bl_send_intensity(bd);
129}
130
131static struct platform_driver hp680bl_driver = {
132 .probe = hp680bl_probe,
133 .remove_new = hp680bl_remove,
134 .driver = {
135 .name = "hp680-bl",
136 .pm = &hp680bl_pm_ops,
137 },
138};
139
140static struct platform_device *hp680bl_device;
141
142static int __init hp680bl_init(void)
143{
144 int ret;
145
146 ret = platform_driver_register(&hp680bl_driver);
147 if (ret)
148 return ret;
149 hp680bl_device = platform_device_register_simple(name: "hp680-bl", id: -1,
150 NULL, num: 0);
151 if (IS_ERR(ptr: hp680bl_device)) {
152 platform_driver_unregister(&hp680bl_driver);
153 return PTR_ERR(ptr: hp680bl_device);
154 }
155 return 0;
156}
157
158static void __exit hp680bl_exit(void)
159{
160 platform_device_unregister(hp680bl_device);
161 platform_driver_unregister(&hp680bl_driver);
162}
163
164module_init(hp680bl_init);
165module_exit(hp680bl_exit);
166
167MODULE_AUTHOR("Andriy Skulysh <askulysh@gmail.com>");
168MODULE_DESCRIPTION("HP Jornada 680 Backlight Driver");
169MODULE_LICENSE("GPL");
170

source code of linux/drivers/video/backlight/hp680_bl.c