From 023f5b2d1fdad6ffe33a204a4e76e38edba9d9e5 Mon Sep 17 00:00:00 2001
From: Kyle McMartin <kyle@dreadnought.i.jkkm.org>
Date: Thu, 20 May 2010 08:59:58 -0400
Subject: linux-2.6-acpi-video-export-edid.patch
 
---
 drivers/acpi/video.c |  110 ++++++++++++++++++++++++++++++++++++++++++++++----
 include/acpi/video.h |   16 +++++++
 2 files changed, 118 insertions(+), 8 deletions(-)
 
diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c
index a0c93b3..4b8bda1 100644
--- a/drivers/acpi/video.c
+++ b/drivers/acpi/video.c
@@ -45,6 +45,7 @@
 #include <acpi/acpi_bus.h>
 #include <acpi/acpi_drivers.h>
 #include <linux/suspend.h>
+#include <acpi/video.h>
 
 #define PREFIX "ACPI: "
 
@@ -65,11 +66,6 @@
 
 #define MAX_NAME_LEN	20
 
-#define ACPI_VIDEO_DISPLAY_CRT	1
-#define ACPI_VIDEO_DISPLAY_TV	2
-#define ACPI_VIDEO_DISPLAY_DVI	3
-#define ACPI_VIDEO_DISPLAY_LCD	4
-
 #define _COMPONENT		ACPI_VIDEO_COMPONENT
 ACPI_MODULE_NAME("video");
 
@@ -1748,11 +1744,27 @@ acpi_video_get_device_attr(struct acpi_video_bus *video, unsigned long device_id
 }
 
 static int
+acpi_video_get_device_type(struct acpi_video_bus *video,
+			   unsigned long device_id)
+{
+	struct acpi_video_enumerated_device *ids;
+	int i;
+
+	for (i = 0; i < video->attached_count; i++) {
+		ids = &video->attached_array[i];
+		if ((ids->value.int_val & 0xffff) == device_id)
+			return ids->value.int_val;
+	}
+
+	return 0;
+}
+
+static int
 acpi_video_bus_get_one_device(struct acpi_device *device,
 			      struct acpi_video_bus *video)
 {
 	unsigned long long device_id;
-	int status;
+	int status, device_type;
 	struct acpi_video_device *data;
 	struct acpi_video_device_attrib* attribute;
 
@@ -1797,8 +1809,25 @@ acpi_video_bus_get_one_device(struct acpi_device *device,
 			}
 			if(attribute->bios_can_detect)
 				data->flags.bios = 1;
-		} else
-			data->flags.unknown = 1;
+		} else {
+			/* Check for legacy IDs */
+			device_type = acpi_video_get_device_type(video,
+								 device_id);
+			/* Ignore bits 16 and 18-20 */
+			switch (device_type & 0xffe2ffff) {
+			case ACPI_VIDEO_DISPLAY_LEGACY_MONITOR:
+				data->flags.crt = 1;
+				break;
+			case ACPI_VIDEO_DISPLAY_LEGACY_PANEL:
+				data->flags.lcd = 1;
+				break;
+			case ACPI_VIDEO_DISPLAY_LEGACY_TV:
+				data->flags.tvout = 1;
+				break;
+			default:
+				data->flags.unknown = 1;
+			}
+		}
 
 		acpi_video_device_bind(video, data);
 		acpi_video_device_find_cap(data);
@@ -2032,6 +2061,71 @@ out:
 	return result;
 }
 
+int acpi_video_get_edid(struct acpi_device *device, int type, int device_id,
+			void **edid)
+{
+	struct acpi_video_bus *video;
+	struct acpi_video_device *video_device;
+	union acpi_object *buffer = NULL;
+	acpi_status status;
+	int i, length;
+
+	if (!device || !acpi_driver_data(device))
+		return -EINVAL;
+
+	video = acpi_driver_data(device);
+
+	for (i = 0; i < video->attached_count; i++) {
+		video_device = video->attached_array[i].bind_info;
+		length = 256;
+
+		if (!video_device)
+			continue;
+
+		if (type) {
+			switch (type) {
+			case ACPI_VIDEO_DISPLAY_CRT:
+				if (!video_device->flags.crt)
+					continue;
+				break;
+			case ACPI_VIDEO_DISPLAY_TV:
+				if (!video_device->flags.tvout)
+					continue;
+				break;
+			case ACPI_VIDEO_DISPLAY_DVI:
+				if (!video_device->flags.dvi)
+					continue;
+				break;
+			case ACPI_VIDEO_DISPLAY_LCD:
+				if (!video_device->flags.lcd)
+					continue;
+				break;
+			}
+		} else if (video_device->device_id != device_id) {
+			continue;
+		}
+
+		status = acpi_video_device_EDID(video_device, &buffer, length);
+
+		if (ACPI_FAILURE(status) || !buffer ||
+		    buffer->type != ACPI_TYPE_BUFFER) {
+			length = 128;
+			status = acpi_video_device_EDID(video_device, &buffer,
+							length);
+			if (ACPI_FAILURE(status) || !buffer ||
+			    buffer->type != ACPI_TYPE_BUFFER) {
+				continue;
+			}
+		}
+
+		*edid = buffer->buffer.pointer;
+		return length;
+	}
+
+	return -ENODEV;
+}
+EXPORT_SYMBOL(acpi_video_get_edid);
+
 static int
 acpi_video_bus_get_devices(struct acpi_video_bus *video,
 			   struct acpi_device *device)
diff --git a/include/acpi/video.h b/include/acpi/video.h
index cf7be3d..551793c 100644
--- a/include/acpi/video.h
+++ b/include/acpi/video.h
@@ -1,12 +1,28 @@
 #ifndef __ACPI_VIDEO_H
 #define __ACPI_VIDEO_H
 
+#define ACPI_VIDEO_DISPLAY_CRT  1
+#define ACPI_VIDEO_DISPLAY_TV   2
+#define ACPI_VIDEO_DISPLAY_DVI  3
+#define ACPI_VIDEO_DISPLAY_LCD  4
+
+#define ACPI_VIDEO_DISPLAY_LEGACY_MONITOR 0x0100
+#define ACPI_VIDEO_DISPLAY_LEGACY_PANEL   0x0110
+#define ACPI_VIDEO_DISPLAY_LEGACY_TV      0x0200
+
 #if (defined CONFIG_ACPI_VIDEO || defined CONFIG_ACPI_VIDEO_MODULE)
 extern int acpi_video_register(void);
 extern void acpi_video_unregister(void);
+extern int acpi_video_get_edid(struct acpi_device *device, int type,
+			       int device_id, void **edid);
 #else
 static inline int acpi_video_register(void) { return 0; }
 static inline void acpi_video_unregister(void) { return; }
+static inline int acpi_video_get_edid(struct acpi_device *device, int type,
+				      int device_id, void **edid)
+{
+	return -ENODEV;
+}
 #endif
 
 #endif
-- 
1.7.0.1