/*
* Backlight driver for OMAP based boards.
*
* Copyright (c) 2006 Andrzej Zaborowski <balrog@zabor.org>
*
* This package 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.
*
* This package is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this package; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/platform_device.h>
#include <linux/fb.h>
#include <linux/backlight.h>
#include <asm/arch/hardware.h>
#include <asm/arch/board.h>
#include <asm/arch/mux.h>
#define OMAPBL_MAX_INTENSITY 0xff
struct omap_backlight {
int powermode;
int current_intensity;
struct device *dev;
struct omap_backlight_config *pdata;
};
static void inline omapbl_send_intensity(int intensity)
{
omap_writeb(intensity, OMAP_PWL_ENABLE);
}
static void inline omapbl_send_enable(int enable)
{
omap_writeb(enable, OMAP_PWL_CLK_ENABLE);
}
static void omapbl_blank(struct omap_backlight *bl, int mode)
{
if (bl->pdata->set_power)
bl->pdata->set_power(bl->dev, mode);
switch (mode) {
case FB_BLANK_NORMAL:
case FB_BLANK_VSYNC_SUSPEND:
case FB_BLANK_HSYNC_SUSPEND:
case FB_BLANK_POWERDOWN:
omapbl_send_intensity(0);
omapbl_send_enable(0);
break;
case FB_BLANK_UNBLANK:
omapbl_send_intensity(bl->current_intensity);
omapbl_send_enable(1);
break;
}
}
#ifdef CONFIG_PM
static int omapbl_suspend(struct platform_device *pdev, pm_message_t state)
{
struct backlight_device *dev = platform_get_drvdata(pdev);
struct omap_backlight *bl = dev_get_drvdata(&dev->dev);
omapbl_blank(bl, FB_BLANK_POWERDOWN);
return 0;
}
static int omapbl_resume(struct platform_device *pdev)
{
struct backlight_device *dev = platform_get_drvdata(pdev);
struct omap_backlight *bl = dev_get_drvdata(&dev->dev);
omapbl_blank(bl, bl->powermode);
return 0;
}
#else
#define omapbl_suspend NULL
#define omapbl_resume NULL
#endif
static int omapbl_set_power(struct backlight_device *dev, int state)
{
struct omap_backlight *bl = dev_get_drvdata(&dev->dev);
omapbl_blank(bl, state);
bl->powermode = state;
return 0;
}
static int omapbl_update_status(struct backlight_device *dev)
{
struct omap_backlight *bl = dev_get_drvdata(&dev->dev);
if (bl->current_intensity != dev->props.brightness) {
if (bl->powermode == FB_BLANK_UNBLANK)
omapbl_send_intensity(dev->props.brightness);
bl->current_intensity = dev->props.brightness;
}
if (dev->props.fb_blank != bl->powermode)
omapbl_set_power(dev, dev->props.fb_blank);
return 0;
}
static int omapbl_get_intensity(struct backlight_device *dev)
{
struct omap_backlight *bl = dev_get_drvdata(&dev->dev);
return bl->current_intensity;
}
static struct backlight_ops omapbl_ops = {
.get_brightness = omapbl_get_intensity,
.update_status = omapbl_update_status,
};
static int omapbl_probe(struct platform_device *pdev)
{
struct backlight_device *dev;
struct omap_backlight *bl;
struct omap_backlight_config *pdata = pdev->dev.platform_data;
if (!pdata)
return -ENXIO;
omapbl_ops.check_fb = pdata->check_fb;
bl = kzalloc(sizeof(struct omap_backlight), GFP_KERNEL);
if (unlikely(!bl))
return -ENOMEM;
dev = backlight_device_register("omap-bl", &pdev->dev, bl, &omapbl_ops);
if (IS_ERR(dev)) {
kfree(bl);
return PTR_ERR(dev);
}
bl->powermode = FB_BLANK_POWERDOWN;
bl->current_intensity = 0;
bl->pdata = pdata;
bl->dev = &pdev->dev;
platform_set_drvdata(pdev, dev);
omap_cfg_reg(PWL); /* Conflicts with UART3 */
dev->props.fb_blank = FB_BLANK_UNBLANK;
dev->props.max_brightness = OMAPBL_MAX_INTENSITY;
dev->props.brightness = pdata->default_intensity;
omapbl_update_status(dev);
printk(KERN_INFO "OMAP LCD backlight initialised\n");
return 0;
}
static int omapbl_remove(struct platform_device *pdev)
{
struct backlight_device *dev = platform_get_drvdata(pdev);
struct omap_backlight *bl = dev_get_drvdata(&dev->dev);
backlight_device_unregister(dev);
kfree(bl);
return 0;
}
static struct platform_driver omapbl_driver = {
.probe = omapbl_probe,
.remove = omapbl_remove,
.suspend = omapbl_suspend,
.resume = omapbl_resume,
.driver = {
.name = "omap-bl",
},
};
static int __init omapbl_init(void)
{
return platform_driver_register(&omapbl_driver);
}
static void __exit omapbl_exit(void)
{
platform_driver_unregister(&omapbl_driver);
}
module_init(omapbl_init);
module_exit(omapbl_exit);
MODULE_AUTHOR("Andrzej Zaborowski <balrog@zabor.org>");
MODULE_DESCRIPTION("OMAP LCD Backlight driver");
MODULE_LICENSE("GPL");
