/*
* Backlight Driver for Nvidia 8600 in Macbook Pro
*
* Copyright (c) Red Hat <mjg@redhat.com>
* Based on code from Pommed:
* Copyright (C) 2006 Nicolas Boichat <nicolas @boichat.ch>
* Copyright (C) 2006 Felipe Alfaro Solana <felipe_alfaro @linuxmail.org>
* Copyright (C) 2007 Julien BLACHE <jb@jblache.org>
*
* 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.
*
* This driver triggers SMIs which cause the firmware to change the
* backlight brightness. This is icky in many ways, but it's impractical to
* get at the firmware code in order to figure out what it's actually doing.
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/platform_device.h>
#include <linux/backlight.h>
#include <linux/err.h>
#include <linux/dmi.h>
#include <linux/io.h>
static struct backlight_device *mbp_backlight_device;
/* Structure to be passed to the DMI_MATCH function. */
struct dmi_match_data {
/* I/O resource to allocate. */
unsigned long iostart;
unsigned long iolen;
/* Backlight operations structure. */
struct backlight_ops backlight_ops;
};
/* Module parameters. */
static int debug;
module_param_named(debug, debug, int, 0644);
MODULE_PARM_DESC(debug, "Set to one to enable debugging messages.");
/*
* Implementation for MacBooks with Intel chipset.
*/
static int intel_chipset_send_intensity(struct backlight_device *bd)
{
int intensity = bd->props.brightness;
if (debug)
printk(KERN_DEBUG "mbp_nvidia_bl: setting brightness to %d\n",
intensity);
outb(0x04 | (intensity << 4), 0xb3);
outb(0xbf, 0xb2);
return 0;
}
static int intel_chipset_get_intensity(struct backlight_device *bd)
{
int intensity;
outb(0x03, 0xb3);
outb(0xbf, 0xb2);
intensity = inb(0xb3) >> 4;
if (debug)
printk(KERN_DEBUG "mbp_nvidia_bl: read brightness of %d\n",
intensity);
return intensity;
}
static const struct dmi_match_data intel_chipset_data = {
.iostart = 0xb2,
.iolen = 2,
.backlight_ops = {
.options = BL_CORE_SUSPENDRESUME,
.get_brightness = intel_chipset_get_intensity,
.update_status = intel_chipset_send_intensity,
}
};
/*
* Implementation for MacBooks with Nvidia chipset.
*/
static int nvidia_chipset_send_intensity(struct backlight_device *bd)
{
int intensity = bd->props.brightness;
if (debug)
printk(KERN_DEBUG "mbp_nvidia_bl: setting brightness to %d\n",
intensity);
outb(0x04 | (intensity << 4), 0x52f);
outb(0xbf, 0x52e);
return 0;
}
static int nvidia_chipset_get_intensity(struct backlight_device *bd)
{
int intensity;
outb(0x03, 0x52f);
outb(0xbf, 0x52e);
intensity = inb(0x52f) >> 4;
if (debug)
printk(KERN_DEBUG "mbp_nvidia_bl: read brightness of %d\n",
intensity);
return intensity;
}
static const struct dmi_match_data nvidia_chipset_data = {
.iostart = 0x52e,
.iolen = 2,
.backlight_ops = {
.options = BL_CORE_SUSPENDRESUME,
.get_brightness = nvidia_chipset_get_intensity,
.update_status = nvidia_chipset_send_intensity
}
};
/*
* DMI matching.
*/
static /* const */ struct dmi_match_data *driver_data;
static int mbp_dmi_match(const struct dmi_system_id *id)
{
driver_data = id->driver_data;
printk(KERN_INFO "mbp_nvidia_bl: %s detected\n", id->ident);
return 1;
}
static const struct dmi_system_id __initdata mbp_device_table[] = {
{
.callback = mbp_dmi_match,
.ident = "MacBookPro 3,1",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro3,1"),
},
.driver_data = (void *)&intel_chipset_data,
},
{
.callback = mbp_dmi_match,
.ident = "MacBookPro 3,2",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro3,2"),
},
.driver_data = (void *)&intel_chipset_data,
},
{
.callback = mbp_dmi_match,
.ident = "MacBookPro 4,1",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro4,1"),
},
.driver_data = (void *)&intel_chipset_data,
},
{
.callback = mbp_dmi_match,
.ident = "MacBook 5,1",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
DMI_MATCH(DMI_PRODUCT_NAME, "MacBook5,1"),
},
.driver_data = (void *)&nvidia_chipset_data,
},
{
.callback = mbp_dmi_match,
.ident = "MacBookAir 2,1",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
DMI_MATCH(DMI_PRODUCT_NAME, "MacBookAir2,1"),
},
.driver_data = (void *)&nvidia_chipset_data,
},
{
.callback = mbp_dmi_match,
.ident = "MacBookPro 5,1",
.matches = {
DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro5,1"),
},
.driver_data = (void *)&nvidia_chipset_data,
},
{ }
};
static int __init mbp_init(void)
{
if (!dmi_check_system(mbp_device_table))
return -ENODEV;
if (!request_region(driver_data->iostart, driver_data->iolen,
"Macbook Pro backlight"))
return -ENXIO;
mbp_backlight_device = backlight_device_register("mbp_backlight",
NULL, NULL, &driver_data->backlight_ops);
if (IS_ERR(mbp_backlight_device)) {
release_region(driver_data->iostart, driver_data->iolen);
return PTR_ERR(mbp_backlight_device);
}
mbp_backlight_device->props.max_brightness = 15;
mbp_backlight_device->props.brightness =
driver_data->backlight_ops.get_brightness(mbp_backlight_device);
backlight_update_status(mbp_backlight_device);
return 0;
}
static void __exit mbp_exit(void)
{
backlight_device_unregister(mbp_backlight_device);
release_region(driver_data->iostart, driver_data->iolen);
}
module_init(mbp_init);
module_exit(mbp_exit);
MODULE_AUTHOR("Matthew Garrett <mjg@redhat.com>");
MODULE_DESCRIPTION("Nvidia-based Macbook Pro Backlight Driver");
MODULE_LICENSE("GPL");
MODULE_DEVICE_TABLE(dmi, mbp_device_table);
