mbp_nvidia_bl: remove DMI dependency

This driver only has to deal with two different classes of hardware, but
right now it needs new DMI entries for every new machine. It turns out
that there's an ACPI device that uniquely identifies Apples with backlights,
so this patch reworks the driver into an ACPI one, identifies the hardware
by checking the PCI vendor of the root bridge and strips out all the DMI
code. It also changes the config text to clarify that it works on devices
other than Macbook Pros and GPUs other than nvidia.

Signed-off-by: Matthew Garrett <mjg@redhat.com>
Acked-by: Richard Purdie <richard.purdie@linuxfoundation.org>
Cc: Mourad De Clerck <mourad@aquazul.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/video/backlight/mbp_nvidia_bl.c b/drivers/video/backlight/mbp_nvidia_bl.c
index 74c3394..b22cfb2 100644
--- a/drivers/video/backlight/mbp_nvidia_bl.c
+++ b/drivers/video/backlight/mbp_nvidia_bl.c
@@ -1,5 +1,5 @@
 /*
- *  Backlight Driver for Nvidia 8600 in Macbook Pro
+ *  Backlight Driver for Macbooks
  *
  *  Copyright (c) Red Hat <mjg@redhat.com>
  *  Based on code from Pommed:
@@ -19,23 +19,27 @@
 #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>
+#include <linux/pci.h>
+#include <linux/acpi.h>
 
-static struct backlight_device *mbp_backlight_device;
+static struct backlight_device *mb_backlight_device;
 
-/* Structure to be passed to the DMI_MATCH function. */
-struct dmi_match_data {
+struct hw_data {
 	/* I/O resource to allocate. */
 	unsigned long iostart;
 	unsigned long iolen;
 	/* Backlight operations structure. */
 	const struct backlight_ops backlight_ops;
+	void (*set_brightness)(int);
 };
 
+static const struct hw_data *hw_data;
+
+#define DRIVER "mb_backlight: "
+
 /* Module parameters. */
 static int debug;
 module_param_named(debug, debug, int, 0644);
@@ -44,16 +48,21 @@
 /*
  * Implementation for MacBooks with Intel chipset.
  */
+static void intel_chipset_set_brightness(int intensity)
+{
+	outb(0x04 | (intensity << 4), 0xb3);
+	outb(0xbf, 0xb2);
+}
+
 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",
+		printk(KERN_DEBUG DRIVER "setting brightness to %d\n",
 		       intensity);
 
-	outb(0x04 | (intensity << 4), 0xb3);
-	outb(0xbf, 0xb2);
+	intel_chipset_set_brightness(intensity);
 	return 0;
 }
 
@@ -66,35 +75,41 @@
 	intensity = inb(0xb3) >> 4;
 
 	if (debug)
-		printk(KERN_DEBUG "mbp_nvidia_bl: read brightness of %d\n",
+		printk(KERN_DEBUG DRIVER "read brightness of %d\n",
 		       intensity);
 
 	return intensity;
 }
 
-static const struct dmi_match_data intel_chipset_data = {
+static const struct hw_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,
-	}
+	},
+	.set_brightness = intel_chipset_set_brightness,
 };
 
 /*
  * Implementation for MacBooks with Nvidia chipset.
  */
+static void nvidia_chipset_set_brightness(int intensity)
+{
+	outb(0x04 | (intensity << 4), 0x52f);
+	outb(0xbf, 0x52e);
+}
+
 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",
+		printk(KERN_DEBUG DRIVER "setting brightness to %d\n",
 		       intensity);
 
-	outb(0x04 | (intensity << 4), 0x52f);
-	outb(0xbf, 0x52e);
+	nvidia_chipset_set_brightness(intensity);
 	return 0;
 }
 
@@ -107,295 +122,106 @@
 	intensity = inb(0x52f) >> 4;
 
 	if (debug)
-		printk(KERN_DEBUG "mbp_nvidia_bl: read brightness of %d\n",
+		printk(KERN_DEBUG DRIVER "read brightness of %d\n",
 		       intensity);
 
 	return intensity;
 }
 
-static const struct dmi_match_data nvidia_chipset_data = {
+static const struct hw_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
-	}
+	},
+	.set_brightness = nvidia_chipset_set_brightness,
 };
 
-/*
- * 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		= "MacBook 1,1",
-		.matches	= {
-			DMI_MATCH(DMI_SYS_VENDOR, "Apple Computer, Inc."),
-			DMI_MATCH(DMI_PRODUCT_NAME, "MacBook1,1"),
-		},
-		.driver_data	= (void *)&intel_chipset_data,
-	},
-	{
-		.callback	= mbp_dmi_match,
-		.ident		= "MacBook 2,1",
-		.matches	= {
-			DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
-			DMI_MATCH(DMI_PRODUCT_NAME, "MacBook2,1"),
-		},
-		.driver_data	= (void *)&intel_chipset_data,
-	},
-	{
-		.callback	= mbp_dmi_match,
-		.ident		= "MacBook 3,1",
-		.matches	= {
-			DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
-			DMI_MATCH(DMI_PRODUCT_NAME, "MacBook3,1"),
-		},
-		.driver_data	= (void *)&intel_chipset_data,
-	},
-	{
-		.callback	= mbp_dmi_match,
-		.ident		= "MacBook 4,1",
-		.matches	= {
-			DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
-			DMI_MATCH(DMI_PRODUCT_NAME, "MacBook4,1"),
-		},
-		.driver_data	= (void *)&intel_chipset_data,
-	},
-	{
-		.callback	= mbp_dmi_match,
-		.ident		= "MacBook 4,2",
-		.matches	= {
-			DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
-			DMI_MATCH(DMI_PRODUCT_NAME, "MacBook4,2"),
-		},
-		.driver_data	= (void *)&intel_chipset_data,
-	},
-	{
-		.callback	= mbp_dmi_match,
-		.ident		= "MacBookPro 1,1",
-		.matches	= {
-			DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
-			DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro1,1"),
-		},
-		.driver_data	= (void *)&intel_chipset_data,
-	},
-	{
-		.callback	= mbp_dmi_match,
-		.ident		= "MacBookPro 1,2",
-		.matches	= {
-			DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
-			DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro1,2"),
-		},
-		.driver_data	= (void *)&intel_chipset_data,
-	},
-	{
-		.callback	= mbp_dmi_match,
-		.ident		= "MacBookPro 2,1",
-		.matches	= {
-			DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
-			DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro2,1"),
-		},
-		.driver_data	= (void *)&intel_chipset_data,
-	},
-	{
-		.callback	= mbp_dmi_match,
-		.ident		= "MacBookPro 2,2",
-		.matches	= {
-			DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
-			DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro2,2"),
-		},
-		.driver_data	= (void *)&intel_chipset_data,
-	},
-	{
-		.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		= "MacBookAir 1,1",
-		.matches	= {
-			DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
-			DMI_MATCH(DMI_PRODUCT_NAME, "MacBookAir1,1"),
-		},
-		.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		= "MacBook 5,2",
-		.matches	= {
-			DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
-			DMI_MATCH(DMI_PRODUCT_NAME, "MacBook5,2"),
-		},
-		.driver_data	= (void *)&nvidia_chipset_data,
-	},
-	{
-		.callback	= mbp_dmi_match,
-		.ident		= "MacBook 6,1",
-		.matches	= {
-			DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
-			DMI_MATCH(DMI_PRODUCT_NAME, "MacBook6,1"),
-		},
-		.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,
-	},
-	{
-		.callback	= mbp_dmi_match,
-		.ident		= "MacBookPro 5,2",
-		.matches	= {
-			DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
-			DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro5,2"),
-		},
-		.driver_data	= (void *)&nvidia_chipset_data,
-	},
-	{
-		.callback	= mbp_dmi_match,
-		.ident		= "MacBookPro 5,3",
-		.matches	= {
-			DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
-			DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro5,3"),
-		},
-		.driver_data	= (void *)&nvidia_chipset_data,
-	},
-	{
-		.callback	= mbp_dmi_match,
-		.ident		= "MacBookPro 5,4",
-		.matches	= {
-			DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
-			DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro5,4"),
-		},
-		.driver_data	= (void *)&nvidia_chipset_data,
-	},
-	{
-		.callback	= mbp_dmi_match,
-		.ident		= "MacBookPro 5,5",
-		.matches	= {
-			DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
-			DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro5,5"),
-		},
-		.driver_data	= (void *)&nvidia_chipset_data,
-	},
-	{
-		.callback	= mbp_dmi_match,
-		.ident		= "MacBookAir 3,1",
-		.matches	= {
-			DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
-			DMI_MATCH(DMI_PRODUCT_NAME, "MacBookAir3,1"),
-		},
-		.driver_data	= (void *)&nvidia_chipset_data,
-	},
-	{
-		.callback	= mbp_dmi_match,
-		.ident		= "MacBookAir 3,2",
-		.matches	= {
-			DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
-			DMI_MATCH(DMI_PRODUCT_NAME, "MacBookAir3,2"),
-		},
-		.driver_data	= (void *)&nvidia_chipset_data,
-	},
-	{ }
-};
-
-static int __init mbp_init(void)
+static int __devinit mb_bl_add(struct acpi_device *dev)
 {
 	struct backlight_properties props;
-	if (!dmi_check_system(mbp_device_table))
-		return -ENODEV;
+	struct pci_dev *host;
 
-	if (!request_region(driver_data->iostart, driver_data->iolen, 
-						"Macbook Pro backlight"))
+	host = pci_get_bus_and_slot(0, 0);
+
+	if (!host) {
+		printk(KERN_ERR DRIVER "unable to find PCI host\n");
+		return -ENODEV;
+	}
+
+	if (host->vendor == PCI_VENDOR_ID_INTEL)
+		hw_data = &intel_chipset_data;
+	else if (host->vendor == PCI_VENDOR_ID_NVIDIA)
+		hw_data = &nvidia_chipset_data;
+
+	pci_dev_put(host);
+
+	if (!hw_data) {
+		printk(KERN_ERR DRIVER "unknown hardware\n");
+		return -ENODEV;
+	}
+
+	if (!request_region(hw_data->iostart, hw_data->iolen,
+			    "Macbook backlight"))
 		return -ENXIO;
 
 	memset(&props, 0, sizeof(struct backlight_properties));
 	props.type = BACKLIGHT_PLATFORM;
 	props.max_brightness = 15;
-	mbp_backlight_device = backlight_device_register("mbp_backlight", NULL,
-							 NULL,
-							 &driver_data->backlight_ops,
-							 &props);
-	if (IS_ERR(mbp_backlight_device)) {
-		release_region(driver_data->iostart, driver_data->iolen);
-		return PTR_ERR(mbp_backlight_device);
+	mb_backlight_device = backlight_device_register("mb_backlight", NULL,
+				    NULL, &hw_data->backlight_ops, &props);
+
+	if (IS_ERR(mb_backlight_device)) {
+		release_region(hw_data->iostart, hw_data->iolen);
+		return PTR_ERR(mb_backlight_device);
 	}
 
-	mbp_backlight_device->props.brightness =
-		driver_data->backlight_ops.get_brightness(mbp_backlight_device);
-	backlight_update_status(mbp_backlight_device);
+	mb_backlight_device->props.brightness =
+		hw_data->backlight_ops.get_brightness(mb_backlight_device);
+	backlight_update_status(mb_backlight_device);
 
 	return 0;
 }
 
-static void __exit mbp_exit(void)
+static int __devexit mb_bl_remove(struct acpi_device *dev, int type)
 {
-	backlight_device_unregister(mbp_backlight_device);
+	backlight_device_unregister(mb_backlight_device);
 
-	release_region(driver_data->iostart, driver_data->iolen);
+	release_region(hw_data->iostart, hw_data->iolen);
+	hw_data = NULL;
+	return 0;
 }
 
-module_init(mbp_init);
-module_exit(mbp_exit);
+static const struct acpi_device_id mb_bl_ids[] = {
+	{"APP0002", 0},
+	{"", 0},
+};
+
+static struct acpi_driver mb_bl_driver = {
+	.name = "Macbook backlight",
+	.ids = mb_bl_ids,
+	.ops = {
+		.add = mb_bl_add,
+		.remove = mb_bl_remove,
+	},
+};
+
+static int __init mb_init(void)
+{
+	return acpi_bus_register_driver(&mb_bl_driver);
+}
+
+static void __exit mb_exit(void)
+{
+	acpi_bus_unregister_driver(&mb_bl_driver);
+}
+
+module_init(mb_init);
+module_exit(mb_exit);
 
 MODULE_AUTHOR("Matthew Garrett <mjg@redhat.com>");
-MODULE_DESCRIPTION("Nvidia-based Macbook Pro Backlight Driver");
+MODULE_DESCRIPTION("Macbook Backlight Driver");
 MODULE_LICENSE("GPL");
-MODULE_DEVICE_TABLE(dmi, mbp_device_table);
+MODULE_DEVICE_TABLE(acpi, mb_bl_ids);