kb3886_bl.c
/*
* Backlight Driver for the KB3886 Backlight
*
* Copyright (c) 2007-2008 Claudio Nieder
*
* Based on corgi_bl.c by Richard Purdie and kb3886 driver by Robert Woerle
*
* 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>
#include <linux/delay.h>
#include <linux/dmi.h>
#define KB3886_PARENT 0x64
#define KB3886_IO 0x60
#define KB3886_ADC_DAC_PWM 0xC4
#define KB3886_PWM0_WRITE 0x81
#define KB3886_PWM0_READ 0x41
static DEFINE_MUTEX(bl_mutex);
static void kb3886_bl_set_intensity(int intensity)
{
mutex_lock(&bl_mutex);
intensity = intensity&0xff;
outb(KB3886_ADC_DAC_PWM, KB3886_PARENT);
usleep_range(10000, 11000);
outb(KB3886_PWM0_WRITE, KB3886_IO);
usleep_range(10000, 11000);
outb(intensity, KB3886_IO);
mutex_unlock(&bl_mutex);
}
struct kb3886bl_machinfo {
int max_intensity;
int default_intensity;
int limit_mask;
void (*set_bl_intensity)(int intensity);
};
static struct kb3886bl_machinfo kb3886_bl_machinfo = {
.max_intensity = 0xff,
.default_intensity = 0xa0,
.limit_mask = 0x7f,
.set_bl_intensity = kb3886_bl_set_intensity,
};
static struct platform_device kb3886bl_device = {
.name = "kb3886-bl",
.dev = {
.platform_data = &kb3886_bl_machinfo,
},
.id = -1,
};
static struct platform_device *devices[] __initdata = {
&kb3886bl_device,
};
/*
* Back to driver
*/
static int kb3886bl_intensity;
static struct backlight_device *kb3886_backlight_device;
static struct kb3886bl_machinfo *bl_machinfo;
static unsigned long kb3886bl_flags;
#define KB3886BL_SUSPENDED 0x01
static struct dmi_system_id kb3886bl_device_table[] __initdata = {
{
.ident = "Sahara Touch-iT",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "SDV"),
DMI_MATCH(DMI_PRODUCT_NAME, "iTouch T201"),
},
},
{ }
};
static int kb3886bl_send_intensity(struct backlight_device *bd)
{
int intensity = bd->props.brightness;
if (bd->props.power != FB_BLANK_UNBLANK)
intensity = 0;
if (bd->props.fb_blank != FB_BLANK_UNBLANK)
intensity = 0;
if (kb3886bl_flags & KB3886BL_SUSPENDED)
intensity = 0;
bl_machinfo->set_bl_intensity(intensity);
kb3886bl_intensity = intensity;
return 0;
}
#ifdef CONFIG_PM_SLEEP
static int kb3886bl_suspend(struct device *dev)
{
struct backlight_device *bd = dev_get_drvdata(dev);
kb3886bl_flags |= KB3886BL_SUSPENDED;
backlight_update_status(bd);
return 0;
}
static int kb3886bl_resume(struct device *dev)
{
struct backlight_device *bd = dev_get_drvdata(dev);
kb3886bl_flags &= ~KB3886BL_SUSPENDED;
backlight_update_status(bd);
return 0;
}
#endif
static SIMPLE_DEV_PM_OPS(kb3886bl_pm_ops, kb3886bl_suspend, kb3886bl_resume);
static int kb3886bl_get_intensity(struct backlight_device *bd)
{
return kb3886bl_intensity;
}
static const struct backlight_ops kb3886bl_ops = {
.get_brightness = kb3886bl_get_intensity,
.update_status = kb3886bl_send_intensity,
};
static int kb3886bl_probe(struct platform_device *pdev)
{
struct backlight_properties props;
struct kb3886bl_machinfo *machinfo = dev_get_platdata(&pdev->dev);
bl_machinfo = machinfo;
if (!machinfo->limit_mask)
machinfo->limit_mask = -1;
memset(&props, 0, sizeof(struct backlight_properties));
props.type = BACKLIGHT_RAW;
props.max_brightness = machinfo->max_intensity;
kb3886_backlight_device = devm_backlight_device_register(&pdev->dev,
"kb3886-bl", &pdev->dev,
NULL, &kb3886bl_ops,
&props);
if (IS_ERR(kb3886_backlight_device))
return PTR_ERR(kb3886_backlight_device);
platform_set_drvdata(pdev, kb3886_backlight_device);
kb3886_backlight_device->props.power = FB_BLANK_UNBLANK;
kb3886_backlight_device->props.brightness = machinfo->default_intensity;
backlight_update_status(kb3886_backlight_device);
return 0;
}
static struct platform_driver kb3886bl_driver = {
.probe = kb3886bl_probe,
.driver = {
.name = "kb3886-bl",
.pm = &kb3886bl_pm_ops,
},
};
static int __init kb3886_init(void)
{
if (!dmi_check_system(kb3886bl_device_table))
return -ENODEV;
platform_add_devices(devices, ARRAY_SIZE(devices));
return platform_driver_register(&kb3886bl_driver);
}
static void __exit kb3886_exit(void)
{
platform_driver_unregister(&kb3886bl_driver);
}
module_init(kb3886_init);
module_exit(kb3886_exit);
MODULE_AUTHOR("Claudio Nieder <private@claudio.ch>");
MODULE_DESCRIPTION("Tabletkiosk Sahara Touch-iT Backlight Driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("dmi:*:svnSDV:pniTouchT201:*");