2 * Backlight Driver for Sharp Zaurus Handhelds (various models)
4 * Copyright (c) 2004-2006 Richard Purdie
6 * Based on Sharp's 2.4 Backlight Driver
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.
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>
20 #include <linux/backlight.h>
21 #include <asm/arch/sharpsl.h>
22 #include <asm/hardware/sharpsl_pm.h>
24 static int corgibl_intensity;
25 static DEFINE_MUTEX(bl_mutex);
26 static struct backlight_properties corgibl_data;
27 static struct backlight_device *corgi_backlight_device;
28 static struct corgibl_machinfo *bl_machinfo;
30 static unsigned long corgibl_flags;
31 #define CORGIBL_SUSPENDED 0x01
32 #define CORGIBL_BATTLOW 0x02
34 static int corgibl_send_intensity(struct backlight_device *bd)
36 void (*corgi_kick_batt)(void);
37 int intensity = bd->props.brightness;
39 if (bd->props.power != FB_BLANK_UNBLANK)
41 if (bd->props.fb_blank != FB_BLANK_UNBLANK)
43 if (corgibl_flags & CORGIBL_SUSPENDED)
45 if (corgibl_flags & CORGIBL_BATTLOW)
46 intensity &= bl_machinfo->limit_mask;
48 mutex_lock(&bl_mutex);
49 bl_machinfo->set_bl_intensity(intensity);
50 mutex_unlock(&bl_mutex);
52 corgibl_intensity = intensity;
54 corgi_kick_batt = symbol_get(sharpsl_battery_kick);
55 if (corgi_kick_batt) {
57 symbol_put(sharpsl_battery_kick);
64 static int corgibl_suspend(struct platform_device *pdev, pm_message_t state)
66 struct backlight_device *bd = platform_get_drvdata(pdev);
68 corgibl_flags |= CORGIBL_SUSPENDED;
69 corgibl_send_intensity(bd);
73 static int corgibl_resume(struct platform_device *pdev)
75 struct backlight_device *bd = platform_get_drvdata(pdev);
77 corgibl_flags &= ~CORGIBL_SUSPENDED;
78 corgibl_send_intensity(bd);
82 #define corgibl_suspend NULL
83 #define corgibl_resume NULL
86 static int corgibl_get_intensity(struct backlight_device *bd)
88 return corgibl_intensity;
92 * Called when the battery is low to limit the backlight intensity.
93 * If limit==0 clear any limit, otherwise limit the intensity
95 void corgibl_limit_intensity(int limit)
98 corgibl_flags |= CORGIBL_BATTLOW;
100 corgibl_flags &= ~CORGIBL_BATTLOW;
101 corgibl_send_intensity(corgi_backlight_device);
103 EXPORT_SYMBOL(corgibl_limit_intensity);
106 static struct backlight_ops corgibl_ops = {
107 .get_brightness = corgibl_get_intensity,
108 .update_status = corgibl_send_intensity,
111 static int corgibl_probe(struct platform_device *pdev)
113 struct corgibl_machinfo *machinfo = pdev->dev.platform_data;
115 bl_machinfo = machinfo;
116 if (!machinfo->limit_mask)
117 machinfo->limit_mask = -1;
119 corgi_backlight_device = backlight_device_register ("corgi-bl",
120 &pdev->dev, NULL, &corgibl_ops);
121 if (IS_ERR (corgi_backlight_device))
122 return PTR_ERR (corgi_backlight_device);
124 platform_set_drvdata(pdev, corgi_backlight_device);
126 corgi_backlight_device->props.max_brightness = machinfo->max_intensity;
127 corgi_backlight_device->props.power = FB_BLANK_UNBLANK;
128 corgi_backlight_device->props.brightness = machinfo->default_intensity;
129 corgibl_send_intensity(corgi_backlight_device);
131 printk("Corgi Backlight Driver Initialized.\n");
135 static int corgibl_remove(struct platform_device *pdev)
137 struct backlight_device *bd = platform_get_drvdata(pdev);
139 corgibl_data.power = 0;
140 corgibl_data.brightness = 0;
141 corgibl_send_intensity(bd);
143 backlight_device_unregister(bd);
145 printk("Corgi Backlight Driver Unloaded\n");
149 static struct platform_driver corgibl_driver = {
150 .probe = corgibl_probe,
151 .remove = corgibl_remove,
152 .suspend = corgibl_suspend,
153 .resume = corgibl_resume,
159 static int __init corgibl_init(void)
161 return platform_driver_register(&corgibl_driver);
164 static void __exit corgibl_exit(void)
166 platform_driver_unregister(&corgibl_driver);
169 module_init(corgibl_init);
170 module_exit(corgibl_exit);
172 MODULE_AUTHOR("Richard Purdie <rpurdie@rpsys.net>");
173 MODULE_DESCRIPTION("Corgi Backlight Driver");
174 MODULE_LICENSE("GPL");