mirror of https://gitee.com/openkylin/linux.git
140 lines
3.4 KiB
C
140 lines
3.4 KiB
C
/*
|
|
* Generic Backlight Driver
|
|
*
|
|
* Copyright (c) 2004-2008 Richard Purdie
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License version 2 as
|
|
* published by the Free Software Foundation.
|
|
*
|
|
*/
|
|
|
|
#include <linux/module.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/init.h>
|
|
#include <linux/platform_device.h>
|
|
#include <linux/mutex.h>
|
|
#include <linux/fb.h>
|
|
#include <linux/backlight.h>
|
|
|
|
static int genericbl_intensity;
|
|
static struct backlight_device *generic_backlight_device;
|
|
static struct generic_bl_info *bl_machinfo;
|
|
|
|
/* Flag to signal when the battery is low */
|
|
#define GENERICBL_BATTLOW BL_CORE_DRIVER1
|
|
|
|
static int genericbl_send_intensity(struct backlight_device *bd)
|
|
{
|
|
int intensity = bd->props.brightness;
|
|
|
|
if (bd->props.power != FB_BLANK_UNBLANK)
|
|
intensity = 0;
|
|
if (bd->props.state & BL_CORE_FBBLANK)
|
|
intensity = 0;
|
|
if (bd->props.state & BL_CORE_SUSPENDED)
|
|
intensity = 0;
|
|
if (bd->props.state & GENERICBL_BATTLOW)
|
|
intensity &= bl_machinfo->limit_mask;
|
|
|
|
bl_machinfo->set_bl_intensity(intensity);
|
|
|
|
genericbl_intensity = intensity;
|
|
|
|
if (bl_machinfo->kick_battery)
|
|
bl_machinfo->kick_battery();
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int genericbl_get_intensity(struct backlight_device *bd)
|
|
{
|
|
return genericbl_intensity;
|
|
}
|
|
|
|
/*
|
|
* Called when the battery is low to limit the backlight intensity.
|
|
* If limit==0 clear any limit, otherwise limit the intensity
|
|
*/
|
|
void genericbl_limit_intensity(int limit)
|
|
{
|
|
struct backlight_device *bd = generic_backlight_device;
|
|
|
|
mutex_lock(&bd->ops_lock);
|
|
if (limit)
|
|
bd->props.state |= GENERICBL_BATTLOW;
|
|
else
|
|
bd->props.state &= ~GENERICBL_BATTLOW;
|
|
backlight_update_status(generic_backlight_device);
|
|
mutex_unlock(&bd->ops_lock);
|
|
}
|
|
EXPORT_SYMBOL(genericbl_limit_intensity);
|
|
|
|
static const struct backlight_ops genericbl_ops = {
|
|
.options = BL_CORE_SUSPENDRESUME,
|
|
.get_brightness = genericbl_get_intensity,
|
|
.update_status = genericbl_send_intensity,
|
|
};
|
|
|
|
static int genericbl_probe(struct platform_device *pdev)
|
|
{
|
|
struct backlight_properties props;
|
|
struct generic_bl_info *machinfo = pdev->dev.platform_data;
|
|
const char *name = "generic-bl";
|
|
struct backlight_device *bd;
|
|
|
|
bl_machinfo = machinfo;
|
|
if (!machinfo->limit_mask)
|
|
machinfo->limit_mask = -1;
|
|
|
|
if (machinfo->name)
|
|
name = machinfo->name;
|
|
|
|
memset(&props, 0, sizeof(struct backlight_properties));
|
|
props.type = BACKLIGHT_RAW;
|
|
props.max_brightness = machinfo->max_intensity;
|
|
bd = backlight_device_register(name, &pdev->dev, NULL, &genericbl_ops,
|
|
&props);
|
|
if (IS_ERR (bd))
|
|
return PTR_ERR (bd);
|
|
|
|
platform_set_drvdata(pdev, bd);
|
|
|
|
bd->props.power = FB_BLANK_UNBLANK;
|
|
bd->props.brightness = machinfo->default_intensity;
|
|
backlight_update_status(bd);
|
|
|
|
generic_backlight_device = bd;
|
|
|
|
printk("Generic Backlight Driver Initialized.\n");
|
|
return 0;
|
|
}
|
|
|
|
static int genericbl_remove(struct platform_device *pdev)
|
|
{
|
|
struct backlight_device *bd = platform_get_drvdata(pdev);
|
|
|
|
bd->props.power = 0;
|
|
bd->props.brightness = 0;
|
|
backlight_update_status(bd);
|
|
|
|
backlight_device_unregister(bd);
|
|
|
|
printk("Generic Backlight Driver Unloaded\n");
|
|
return 0;
|
|
}
|
|
|
|
static struct platform_driver genericbl_driver = {
|
|
.probe = genericbl_probe,
|
|
.remove = genericbl_remove,
|
|
.driver = {
|
|
.name = "generic-bl",
|
|
},
|
|
};
|
|
|
|
module_platform_driver(genericbl_driver);
|
|
|
|
MODULE_AUTHOR("Richard Purdie <rpurdie@rpsys.net>");
|
|
MODULE_DESCRIPTION("Generic Backlight Driver");
|
|
MODULE_LICENSE("GPL");
|