173 lines
4.5 KiB
C
173 lines
4.5 KiB
C
/*
|
|
* Copyright (C) 2009-2010, Lars-Peter Clausen <lars@metafoo.de>
|
|
* PCF50633 backlight device driver
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify it
|
|
* under the terms of the GNU General Public License as published by the
|
|
* Free Software Foundation; either version 2 of the License, or (at your
|
|
* option) any later version.
|
|
*
|
|
* You should have received a copy of the GNU General Public License along
|
|
* with this program; if not, write to the Free Software Foundation, Inc.,
|
|
* 675 Mass Ave, Cambridge, MA 02139, USA.
|
|
*
|
|
*/
|
|
|
|
#include <linux/kernel.h>
|
|
#include <linux/module.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/platform_device.h>
|
|
|
|
#include <linux/backlight.h>
|
|
#include <linux/fb.h>
|
|
|
|
#include <linux/mfd/pcf50633/core.h>
|
|
#include <linux/mfd/pcf50633/backlight.h>
|
|
|
|
struct pcf50633_bl {
|
|
struct pcf50633 *pcf;
|
|
struct backlight_device *bl;
|
|
|
|
unsigned int brightness;
|
|
unsigned int brightness_limit;
|
|
};
|
|
|
|
/*
|
|
* pcf50633_bl_set_brightness_limit
|
|
*
|
|
* Update the brightness limit for the pc50633 backlight. The actual brightness
|
|
* will not go above the limit. This is useful to limit power drain for example
|
|
* on low battery.
|
|
*
|
|
* @dev: Pointer to a pcf50633 device
|
|
* @limit: The brightness limit. Valid values are 0-63
|
|
*/
|
|
int pcf50633_bl_set_brightness_limit(struct pcf50633 *pcf, unsigned int limit)
|
|
{
|
|
struct pcf50633_bl *pcf_bl = platform_get_drvdata(pcf->bl_pdev);
|
|
|
|
if (!pcf_bl)
|
|
return -ENODEV;
|
|
|
|
pcf_bl->brightness_limit = limit & 0x3f;
|
|
backlight_update_status(pcf_bl->bl);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int pcf50633_bl_update_status(struct backlight_device *bl)
|
|
{
|
|
struct pcf50633_bl *pcf_bl = bl_get_data(bl);
|
|
unsigned int new_brightness;
|
|
|
|
|
|
if (bl->props.state & (BL_CORE_SUSPENDED | BL_CORE_FBBLANK) ||
|
|
bl->props.power != FB_BLANK_UNBLANK)
|
|
new_brightness = 0;
|
|
else if (bl->props.brightness < pcf_bl->brightness_limit)
|
|
new_brightness = bl->props.brightness;
|
|
else
|
|
new_brightness = pcf_bl->brightness_limit;
|
|
|
|
|
|
if (pcf_bl->brightness == new_brightness)
|
|
return 0;
|
|
|
|
if (new_brightness) {
|
|
pcf50633_reg_write(pcf_bl->pcf, PCF50633_REG_LEDOUT,
|
|
new_brightness);
|
|
if (!pcf_bl->brightness)
|
|
pcf50633_reg_write(pcf_bl->pcf, PCF50633_REG_LEDENA, 1);
|
|
} else {
|
|
pcf50633_reg_write(pcf_bl->pcf, PCF50633_REG_LEDENA, 0);
|
|
}
|
|
|
|
pcf_bl->brightness = new_brightness;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int pcf50633_bl_get_brightness(struct backlight_device *bl)
|
|
{
|
|
struct pcf50633_bl *pcf_bl = bl_get_data(bl);
|
|
return pcf_bl->brightness;
|
|
}
|
|
|
|
static const struct backlight_ops pcf50633_bl_ops = {
|
|
.get_brightness = pcf50633_bl_get_brightness,
|
|
.update_status = pcf50633_bl_update_status,
|
|
.options = BL_CORE_SUSPENDRESUME,
|
|
};
|
|
|
|
static int __devinit pcf50633_bl_probe(struct platform_device *pdev)
|
|
{
|
|
struct pcf50633_bl *pcf_bl;
|
|
struct device *parent = pdev->dev.parent;
|
|
struct pcf50633_platform_data *pcf50633_data = parent->platform_data;
|
|
struct pcf50633_bl_platform_data *pdata = pcf50633_data->backlight_data;
|
|
struct backlight_properties bl_props;
|
|
|
|
pcf_bl = devm_kzalloc(&pdev->dev, sizeof(*pcf_bl), GFP_KERNEL);
|
|
if (!pcf_bl)
|
|
return -ENOMEM;
|
|
|
|
memset(&bl_props, 0, sizeof(bl_props));
|
|
bl_props.type = BACKLIGHT_RAW;
|
|
bl_props.max_brightness = 0x3f;
|
|
bl_props.power = FB_BLANK_UNBLANK;
|
|
|
|
if (pdata) {
|
|
bl_props.brightness = pdata->default_brightness;
|
|
pcf_bl->brightness_limit = pdata->default_brightness_limit;
|
|
} else {
|
|
bl_props.brightness = 0x3f;
|
|
pcf_bl->brightness_limit = 0x3f;
|
|
}
|
|
|
|
pcf_bl->pcf = dev_to_pcf50633(pdev->dev.parent);
|
|
|
|
pcf_bl->bl = backlight_device_register(pdev->name, &pdev->dev, pcf_bl,
|
|
&pcf50633_bl_ops, &bl_props);
|
|
|
|
if (IS_ERR(pcf_bl->bl))
|
|
return PTR_ERR(pcf_bl->bl);
|
|
|
|
platform_set_drvdata(pdev, pcf_bl);
|
|
|
|
pcf50633_reg_write(pcf_bl->pcf, PCF50633_REG_LEDDIM, pdata->ramp_time);
|
|
|
|
/* Should be different from bl_props.brightness, so we do not exit
|
|
* update_status early the first time it's called */
|
|
pcf_bl->brightness = pcf_bl->bl->props.brightness + 1;
|
|
|
|
backlight_update_status(pcf_bl->bl);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int __devexit pcf50633_bl_remove(struct platform_device *pdev)
|
|
{
|
|
struct pcf50633_bl *pcf_bl = platform_get_drvdata(pdev);
|
|
|
|
backlight_device_unregister(pcf_bl->bl);
|
|
|
|
platform_set_drvdata(pdev, NULL);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static struct platform_driver pcf50633_bl_driver = {
|
|
.probe = pcf50633_bl_probe,
|
|
.remove = __devexit_p(pcf50633_bl_remove),
|
|
.driver = {
|
|
.name = "pcf50633-backlight",
|
|
},
|
|
};
|
|
|
|
module_platform_driver(pcf50633_bl_driver);
|
|
|
|
MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
|
|
MODULE_DESCRIPTION("PCF50633 backlight driver");
|
|
MODULE_LICENSE("GPL");
|
|
MODULE_ALIAS("platform:pcf50633-backlight");
|