2 * Backlight Driver for Sharp Corgi
4 * Copyright (c) 2004-2005 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/device.h>
18 #include <linux/spinlock.h>
20 #include <linux/backlight.h>
22 #include <asm/arch-pxa/corgi.h>
23 #include <asm/hardware/scoop.h>
25 #define CORGI_MAX_INTENSITY 0x3e
26 #define CORGI_DEFAULT_INTENSITY 0x1f
27 #define CORGI_LIMIT_MASK 0x0b
29 static int corgibl_powermode
= FB_BLANK_UNBLANK
;
30 static int current_intensity
= 0;
31 static int corgibl_limit
= 0;
32 static spinlock_t bl_lock
= SPIN_LOCK_UNLOCKED
;
34 static void corgibl_send_intensity(int intensity
)
37 void (*corgi_kick_batt
)(void);
39 if (corgibl_powermode
!= FB_BLANK_UNBLANK
) {
43 intensity
&= CORGI_LIMIT_MASK
;
46 spin_lock_irqsave(&bl_lock
, flags
);
48 corgibl_mach_set_intensity(intensity
);
50 spin_unlock_irqrestore(&bl_lock
, flags
);
53 static void corgibl_blank(int blank
)
58 case FB_BLANK_VSYNC_SUSPEND
:
59 case FB_BLANK_HSYNC_SUSPEND
:
60 case FB_BLANK_POWERDOWN
:
61 if (corgibl_powermode
== FB_BLANK_UNBLANK
) {
62 corgibl_send_intensity(0);
63 corgibl_powermode
= blank
;
66 case FB_BLANK_UNBLANK
:
67 if (corgibl_powermode
!= FB_BLANK_UNBLANK
) {
68 corgibl_powermode
= blank
;
69 corgibl_send_intensity(current_intensity
);
76 static int corgibl_suspend(struct device
*dev
, pm_message_t state
, u32 level
)
78 if (level
== SUSPEND_POWER_DOWN
)
79 corgibl_blank(FB_BLANK_POWERDOWN
);
83 static int corgibl_resume(struct device
*dev
, u32 level
)
85 if (level
== RESUME_POWER_ON
)
86 corgibl_blank(FB_BLANK_UNBLANK
);
90 #define corgibl_suspend NULL
91 #define corgibl_resume NULL
95 static int corgibl_set_power(struct backlight_device
*bd
, int state
)
101 static int corgibl_get_power(struct backlight_device
*bd
)
103 return corgibl_powermode
;
106 static int corgibl_set_intensity(struct backlight_device
*bd
, int intensity
)
108 if (intensity
> corgibl_data
.max_brightness
)
109 intensity
= corgibl_data
.max_brightness
;
110 corgibl_send_intensity(intensity
);
111 current_intensity
=intensity
;
115 static int corgibl_get_intensity(struct backlight_device
*bd
)
117 return current_intensity
;
121 * Called when the battery is low to limit the backlight intensity.
122 * If limit==0 clear any limit, otherwise limit the intensity
124 void corgibl_limit_intensity(int limit
)
126 corgibl_limit
= (limit
? 1 : 0);
127 corgibl_send_intensity(current_intensity
);
129 EXPORT_SYMBOL(corgibl_limit_intensity
);
132 static struct backlight_properties corgibl_data
= {
133 .owner
= THIS_MODULE
,
134 .get_power
= corgibl_get_power
,
135 .set_power
= corgibl_set_power
,
136 .get_brightness
= corgibl_get_intensity
,
137 .set_brightness
= corgibl_set_intensity
,
140 static struct backlight_device
*corgi_backlight_device
;
142 static int __init
corgibl_probe(struct device
*dev
)
144 struct corgibl_machinfo
*machinfo
= dev
->platform_data
;
146 corgibl_data
.max_brightness
= machinfo
->max_intensity
;
147 corgibl_mach_set_intensity
= machinfo
->set_bl_intensity
;
149 corgi_backlight_device
= backlight_device_register ("corgi-bl",
150 NULL
, &corgibl_data
);
151 if (IS_ERR (corgi_backlight_device
))
152 return PTR_ERR (corgi_backlight_device
);
154 corgibl_set_intensity(NULL
, CORGI_DEFAULT_INTENSITY
);
155 corgibl_limit_intensity(0);
157 printk("Corgi Backlight Driver Initialized.\n");
161 static int corgibl_remove(struct device
*dev
)
163 backlight_device_unregister(corgi_backlight_device
);
165 corgibl_set_intensity(NULL
, 0);
167 printk("Corgi Backlight Driver Unloaded\n");
171 static struct device_driver corgibl_driver
= {
173 .bus
= &platform_bus_type
,
174 .probe
= corgibl_probe
,
175 .remove
= corgibl_remove
,
176 .suspend
= corgibl_suspend
,
177 .resume
= corgibl_resume
,
180 static int __init
corgibl_init(void)
182 return driver_register(&corgibl_driver
);
185 static void __exit
corgibl_exit(void)
187 driver_unregister(&corgibl_driver
);
190 module_init(corgibl_init
);
191 module_exit(corgibl_exit
);
193 MODULE_AUTHOR("Richard Purdie <rpurdie@rpsys.net>");
194 MODULE_DESCRIPTION("Corgi Backlight Driver");
195 MODULE_LICENSE("GPLv2");