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
28 static int hp680bl_suspended;
29 static int current_intensity;
30 static DEFINE_SPINLOCK(bl_lock);
31
hp680bl_send_intensity(struct backlight_device * bd)32 static 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_SLEEP
hp680bl_suspend(struct device * dev)68 static int hp680bl_suspend(struct device *dev)
69 {
70 struct backlight_device *bd = dev_get_drvdata(dev);
71
72 hp680bl_suspended = 1;
73 hp680bl_send_intensity(bd);
74 return 0;
75 }
76
hp680bl_resume(struct device * dev)77 static int hp680bl_resume(struct device *dev)
78 {
79 struct backlight_device *bd = dev_get_drvdata(dev);
80
81 hp680bl_suspended = 0;
82 hp680bl_send_intensity(bd);
83 return 0;
84 }
85 #endif
86
87 static SIMPLE_DEV_PM_OPS(hp680bl_pm_ops, hp680bl_suspend, hp680bl_resume);
88
hp680bl_set_intensity(struct backlight_device * bd)89 static int hp680bl_set_intensity(struct backlight_device *bd)
90 {
91 hp680bl_send_intensity(bd);
92 return 0;
93 }
94
hp680bl_get_intensity(struct backlight_device * bd)95 static int hp680bl_get_intensity(struct backlight_device *bd)
96 {
97 return current_intensity;
98 }
99
100 static const struct backlight_ops hp680bl_ops = {
101 .get_brightness = hp680bl_get_intensity,
102 .update_status = hp680bl_set_intensity,
103 };
104
hp680bl_probe(struct platform_device * pdev)105 static int hp680bl_probe(struct platform_device *pdev)
106 {
107 struct backlight_properties props;
108 struct backlight_device *bd;
109
110 memset(&props, 0, sizeof(struct backlight_properties));
111 props.type = BACKLIGHT_RAW;
112 props.max_brightness = HP680_MAX_INTENSITY;
113 bd = devm_backlight_device_register(&pdev->dev, "hp680-bl", &pdev->dev,
114 NULL, &hp680bl_ops, &props);
115 if (IS_ERR(bd))
116 return PTR_ERR(bd);
117
118 platform_set_drvdata(pdev, bd);
119
120 bd->props.brightness = HP680_DEFAULT_INTENSITY;
121 hp680bl_send_intensity(bd);
122
123 return 0;
124 }
125
hp680bl_remove(struct platform_device * pdev)126 static int hp680bl_remove(struct platform_device *pdev)
127 {
128 struct backlight_device *bd = platform_get_drvdata(pdev);
129
130 bd->props.brightness = 0;
131 bd->props.power = 0;
132 hp680bl_send_intensity(bd);
133
134 return 0;
135 }
136
137 static struct platform_driver hp680bl_driver = {
138 .probe = hp680bl_probe,
139 .remove = hp680bl_remove,
140 .driver = {
141 .name = "hp680-bl",
142 .pm = &hp680bl_pm_ops,
143 },
144 };
145
146 static struct platform_device *hp680bl_device;
147
hp680bl_init(void)148 static int __init hp680bl_init(void)
149 {
150 int ret;
151
152 ret = platform_driver_register(&hp680bl_driver);
153 if (ret)
154 return ret;
155 hp680bl_device = platform_device_register_simple("hp680-bl", -1,
156 NULL, 0);
157 if (IS_ERR(hp680bl_device)) {
158 platform_driver_unregister(&hp680bl_driver);
159 return PTR_ERR(hp680bl_device);
160 }
161 return 0;
162 }
163
hp680bl_exit(void)164 static void __exit hp680bl_exit(void)
165 {
166 platform_device_unregister(hp680bl_device);
167 platform_driver_unregister(&hp680bl_driver);
168 }
169
170 module_init(hp680bl_init);
171 module_exit(hp680bl_exit);
172
173 MODULE_AUTHOR("Andriy Skulysh <askulysh@gmail.com>");
174 MODULE_DESCRIPTION("HP Jornada 680 Backlight Driver");
175 MODULE_LICENSE("GPL");
176