acrn-kernel/drivers/video/backlight/platform_lcd.c

163 lines
3.5 KiB
C

/* drivers/video/backlight/platform_lcd.c
*
* Copyright 2008 Simtec Electronics
* Ben Dooks <ben@simtec.co.uk>
*
* Generic platform-device LCD power control interface.
*
* 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/platform_device.h>
#include <linux/fb.h>
#include <linux/backlight.h>
#include <linux/lcd.h>
#include <linux/of.h>
#include <linux/slab.h>
#include <video/platform_lcd.h>
struct platform_lcd {
struct device *us;
struct lcd_device *lcd;
struct plat_lcd_data *pdata;
unsigned int power;
unsigned int suspended:1;
};
static inline struct platform_lcd *to_our_lcd(struct lcd_device *lcd)
{
return lcd_get_data(lcd);
}
static int platform_lcd_get_power(struct lcd_device *lcd)
{
struct platform_lcd *plcd = to_our_lcd(lcd);
return plcd->power;
}
static int platform_lcd_set_power(struct lcd_device *lcd, int power)
{
struct platform_lcd *plcd = to_our_lcd(lcd);
int lcd_power = 1;
if (power == FB_BLANK_POWERDOWN || plcd->suspended)
lcd_power = 0;
plcd->pdata->set_power(plcd->pdata, lcd_power);
plcd->power = power;
return 0;
}
static int platform_lcd_match(struct lcd_device *lcd, struct fb_info *info)
{
struct platform_lcd *plcd = to_our_lcd(lcd);
struct plat_lcd_data *pdata = plcd->pdata;
if (pdata->match_fb)
return pdata->match_fb(pdata, info);
return plcd->us->parent == info->device;
}
static struct lcd_ops platform_lcd_ops = {
.get_power = platform_lcd_get_power,
.set_power = platform_lcd_set_power,
.check_fb = platform_lcd_match,
};
static int platform_lcd_probe(struct platform_device *pdev)
{
struct plat_lcd_data *pdata;
struct platform_lcd *plcd;
struct device *dev = &pdev->dev;
int err;
pdata = dev_get_platdata(&pdev->dev);
if (!pdata) {
dev_err(dev, "no platform data supplied\n");
return -EINVAL;
}
if (pdata->probe) {
err = pdata->probe(pdata);
if (err)
return err;
}
plcd = devm_kzalloc(&pdev->dev, sizeof(struct platform_lcd),
GFP_KERNEL);
if (!plcd)
return -ENOMEM;
plcd->us = dev;
plcd->pdata = pdata;
plcd->lcd = devm_lcd_device_register(&pdev->dev, dev_name(dev), dev,
plcd, &platform_lcd_ops);
if (IS_ERR(plcd->lcd)) {
dev_err(dev, "cannot register lcd device\n");
return PTR_ERR(plcd->lcd);
}
platform_set_drvdata(pdev, plcd);
platform_lcd_set_power(plcd->lcd, FB_BLANK_NORMAL);
return 0;
}
#ifdef CONFIG_PM_SLEEP
static int platform_lcd_suspend(struct device *dev)
{
struct platform_lcd *plcd = dev_get_drvdata(dev);
plcd->suspended = 1;
platform_lcd_set_power(plcd->lcd, plcd->power);
return 0;
}
static int platform_lcd_resume(struct device *dev)
{
struct platform_lcd *plcd = dev_get_drvdata(dev);
plcd->suspended = 0;
platform_lcd_set_power(plcd->lcd, plcd->power);
return 0;
}
#endif
static SIMPLE_DEV_PM_OPS(platform_lcd_pm_ops, platform_lcd_suspend,
platform_lcd_resume);
#ifdef CONFIG_OF
static const struct of_device_id platform_lcd_of_match[] = {
{ .compatible = "platform-lcd" },
{},
};
MODULE_DEVICE_TABLE(of, platform_lcd_of_match);
#endif
static struct platform_driver platform_lcd_driver = {
.driver = {
.name = "platform-lcd",
.owner = THIS_MODULE,
.pm = &platform_lcd_pm_ops,
.of_match_table = of_match_ptr(platform_lcd_of_match),
},
.probe = platform_lcd_probe,
};
module_platform_driver(platform_lcd_driver);
MODULE_AUTHOR("Ben Dooks <ben-linux@fluff.org>");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("platform:platform-lcd");