diff --git a/src/add-ons/accelerants/radeon_hd/display.cpp b/src/add-ons/accelerants/radeon_hd/display.cpp
index d09bd8f58db..7b212ee090a 100644
--- a/src/add-ons/accelerants/radeon_hd/display.cpp
+++ b/src/add-ons/accelerants/radeon_hd/display.cpp
@@ -1,5 +1,5 @@
 /*
- * Copyright 2006-2011, Haiku, Inc. All Rights Reserved.
+ * Copyright 2006-2013, Haiku, Inc. All Rights Reserved.
  * Distributed under the terms of the MIT License.
  *
  * Authors:
@@ -21,6 +21,7 @@
 #include "accelerant_protos.h"
 #include "bios.h"
 #include "connector.h"
+#include "displayport.h"
 #include "encoder.h"
 
 
@@ -225,8 +226,7 @@ detect_crt_ranges(uint32 crtid)
 		edid1_detailed_monitor* monitor
 			= &edid->detailed_monitor[index];
 
-		if (monitor->monitor_desc_type
-			== EDID1_MONITOR_RANGES) {
+		if (monitor->monitor_desc_type == EDID1_MONITOR_RANGES) {
 			edid1_monitor_range range = monitor->data.monitor_range;
 			gDisplay[crtid]->vfreqMin = range.min_v;   /* in Hz */
 			gDisplay[crtid]->vfreqMax = range.max_v;
@@ -258,11 +258,24 @@ detect_displays()
 			continue;
 
 		if (gConnector[id]->type == VIDEO_CONNECTOR_9DIN) {
-			TRACE("%s: Skipping 9DIN connector (not yet supported)\n",
-				__func__);
+			TRACE("%s: connector(%" B_PRIu32 "): Skipping 9DIN connector "
+				"(not yet supported)\n", __func__, id);
 			continue;
 		}
 
+		if (gConnector[id]->type == VIDEO_CONNECTOR_DP) {
+			edid1_info* edid = &gDisplay[displayIndex]->edidData;
+
+			TRACE("%s: connector(%" B_PRIu32 "): Checking DP.\n", __func__, id);
+			status_t dpHasEDID = ddc2_dp_read_edid1(id, edid);
+			gDisplay[displayIndex]->attached
+				= (dpHasEDID == B_OK ? true : false);
+			if (gDisplay[displayIndex]->attached) {
+				TRACE("%s: connector(%" B_PRIu32 "): Found DisplayPort EDID!\n",
+					__func__);
+			}
+		}
+
 		// TODO: As DP aux transactions don't work yet, just use LVDS as a hack
 		#if 0
 		if (gConnector[id]->encoderExternal.isDPBridge == true) {
@@ -276,17 +289,22 @@ detect_displays()
 			// TODO: DDC Router switching for DisplayPort (and others?)
 		} else if (gConnector[id]->type == VIDEO_CONNECTOR_LVDS) {
 		#endif
-		if (gConnector[id]->type == VIDEO_CONNECTOR_LVDS) {
+
+		if (gDisplay[displayIndex]->attached == false
+			&& gConnector[id]->type == VIDEO_CONNECTOR_LVDS) {
 			// If plain (non-DP) laptop LVDS, read mode info from AtomBIOS
 			//TRACE("%s: non-DP laptop LVDS detected\n", __func__);
-			gDisplay[displayIndex]->attached
-				= connector_read_mode_lvds(id,
-					&gDisplay[displayIndex]->preferredMode);
+			gDisplay[displayIndex]->attached = connector_read_mode_lvds(id,
+				&gDisplay[displayIndex]->preferredMode);
+			if (gDisplay[displayIndex]->attached) {
+				TRACE("%s: connector(%" B_PRIu32 "): found LVDS preferred "
+					"mode\n", __func__, id);
+			}
 		}
 
 		// If no display found yet, try more standard detection methods
 		if (gDisplay[displayIndex]->attached == false) {
-			TRACE("%s: bit-banging ddc for EDID on connector %" B_PRIu32 "\n",
+			TRACE("%s: connector(%" B_PRIu32 "): bit-banging ddc for EDID.\n",
 				__func__, id);
 
 			// Lets try bit-banging edid from connector
@@ -299,7 +317,7 @@ detect_displays()
 
 			// Found EDID data?
 			if (gDisplay[displayIndex]->attached) {
-				TRACE("%s: found EDID data on connector %" B_PRIu32 "\n",
+				TRACE("%s: connector(%" B_PRIu32 "): found EDID data.\n",
 					__func__, id);
 
 				bool analogEncoder
@@ -309,20 +327,20 @@ detect_displays()
 				edid1_info* edid = &gDisplay[displayIndex]->edidData;
 				if (!edid->display.input_type && analogEncoder) {
 					// If non-digital EDID + the encoder is analog...
-					TRACE("%s: connector %" B_PRIu32 " has non-digital EDID "
+					TRACE("%s: connector(%" B_PRIu32 "): has non-digital EDID "
 						"and a analog encoder.\n", __func__, id);
 					gDisplay[displayIndex]->attached
 						= encoder_analog_load_detect(id);
 				} else if (edid->display.input_type && !analogEncoder) {
 					// If EDID is digital, we make an assumption here.
-					TRACE("%s: connector %" B_PRIu32 " has digital EDID "
+					TRACE("%s: connector(%" B_PRIu32 "): has digital EDID "
 						"and is not a analog encoder.\n", __func__, id);
 				} else {
 					// This generally means the monitor is of poor design
 					// Since we *know* there is no load on the analog encoder
 					// we assume that it is a digital display.
-					TRACE("%s: Warning: monitor on connector %" B_PRIu32 " has "
-						"false digital EDID flag and unloaded analog encoder!\n",
+					TRACE("%s: connector(%" B_PRIu32 "): Warning: monitor has "
+						"false digital EDID flag + unloaded analog encoder!\n",
 						__func__, id);
 				}
 			}
diff --git a/src/add-ons/accelerants/radeon_hd/displayport.cpp b/src/add-ons/accelerants/radeon_hd/displayport.cpp
index 2aff239213d..3acd66d2673 100644
--- a/src/add-ons/accelerants/radeon_hd/displayport.cpp
+++ b/src/add-ons/accelerants/radeon_hd/displayport.cpp
@@ -1,9 +1,10 @@
 /*
- * Copyright 2011, Haiku, Inc. All Rights Reserved.
+ * Copyright 2011-2013, Haiku, Inc. All Rights Reserved.
  * Distributed under the terms of the MIT License.
  *
  * Authors:
  *		Alexander von Gluck IV, kallisti5@unixzen.com
+ *		Bill Randle, billr@neocat.org
  */
 
 
@@ -178,14 +179,14 @@ dpcd_reg_read(uint32 hwPin, uint16 address)
 
 
 status_t
-dp_aux_get_i2c_byte(uint32 hwPin, uint16 address, uint8* data, bool end)
+dp_aux_get_i2c_byte(uint32 hwPin, uint16 address, uint8* data, bool start, bool stop)
 {
 	uint8 auxMessage[5];
 	int auxMessageBytes = 4; // 4 for read
 
 	/* Set up the command byte */
 	auxMessage[2] = AUX_I2C_READ << 4;
-	if (end == false)
+	if (stop == false)
 		auxMessage[2] |= AUX_I2C_MOT << 4;
 
 	auxMessage[0] = address;
@@ -193,6 +194,12 @@ dp_aux_get_i2c_byte(uint32 hwPin, uint16 address, uint8* data, bool end)
 
 	auxMessage[3] = auxMessageBytes << 4;
 
+	/* special case for sending the START or STOP */
+	if (start || stop) {
+		auxMessage[3] = 3 << 4;
+		auxMessageBytes = 4;
+	}
+
 	int retry;
 	for (retry = 0; retry < 4; retry++) {
 		uint8 ack;
@@ -249,14 +256,14 @@ dp_aux_get_i2c_byte(uint32 hwPin, uint16 address, uint8* data, bool end)
 
 
 status_t
-dp_aux_set_i2c_byte(uint32 hwPin, uint16 address, uint8* data, bool end)
+dp_aux_set_i2c_byte(uint32 hwPin, uint16 address, uint8* data, bool start, bool stop)
 {
 	uint8 auxMessage[5];
 	int auxMessageBytes = 5; // 5 for write
 
 	/* Set up the command byte */
 	auxMessage[2] = AUX_I2C_WRITE << 4;
-	if (end == false)
+	if (stop == false)
 		auxMessage[2] |= AUX_I2C_MOT << 4;
 
 	auxMessage[0] = address;
@@ -265,6 +272,12 @@ dp_aux_set_i2c_byte(uint32 hwPin, uint16 address, uint8* data, bool end)
 	auxMessage[3] = auxMessageBytes << 4;
 	auxMessage[4] = *data;
 
+	/* special case for sending the START or STOP */
+	if (start || stop) {
+		auxMessage[3] = 3 << 4;
+		auxMessageBytes = 4;
+	}
+
 	int retry;
 	for (retry = 0; retry < 4; retry++) {
 		uint8 ack;
@@ -328,7 +341,7 @@ dp_get_lane_count(uint32 connectorIndex, display_mode* mode)
 
 	size_t pixelChunk;
 	size_t pixelsPerChunk;
-	status_t result = get_pixel_size_for((color_space)mode->space, &pixelChunk,
+	status_t result = dp_get_pixel_size_for((color_space)mode->space, &pixelChunk,
 		NULL, &pixelsPerChunk);
 
 	if (result != B_OK) {
@@ -367,7 +380,7 @@ dp_get_link_rate(uint32 connectorIndex, display_mode* mode)
 
 	size_t pixelChunk;
 	size_t pixelsPerChunk;
-	status_t result = get_pixel_size_for((color_space)mode->space, &pixelChunk,
+	status_t result = dp_get_pixel_size_for((color_space)mode->space, &pixelChunk,
 		NULL, &pixelsPerChunk);
 
 	if (result != B_OK) {
@@ -859,6 +872,74 @@ dp_link_train(uint32 connectorIndex, display_mode* mode)
 }
 
 
+status_t
+ddc2_dp_read_edid1(uint32 connectorIndex, edid1_info* edid)
+{
+	TRACE("%s\n", __func__);
+
+	dp_info* dpInfo = &gConnector[connectorIndex]->dpInfo;
+
+	if (!dpInfo->valid)
+		return B_ERROR;
+
+	edid1_raw raw;
+	uint8* rdata = (uint8_t*)&raw;
+	uint8 sdata = 0;
+
+	// The following sequence is from a trace of the Linux kernel
+	// radeon code; not sure if the initial writes to address 0 are
+	// requried.
+	dp_aux_set_i2c_byte(dpInfo->auxPin, 0x00, &sdata, true, false);
+	dp_aux_set_i2c_byte(dpInfo->auxPin, 0x00, &sdata, false, true);
+
+	dp_aux_set_i2c_byte(dpInfo->auxPin, 0x50, &sdata, true, false);
+	dp_aux_set_i2c_byte(dpInfo->auxPin, 0x50, &sdata, false, false);
+	dp_aux_get_i2c_byte(dpInfo->auxPin, 0x50, rdata, true, false);
+	dp_aux_get_i2c_byte(dpInfo->auxPin, 0x50, rdata, false, false);
+	dp_aux_get_i2c_byte(dpInfo->auxPin, 0x50, rdata, false, true);
+	dp_aux_set_i2c_byte(dpInfo->auxPin, 0x50, &sdata, true, false);
+	dp_aux_set_i2c_byte(dpInfo->auxPin, 0x50, &sdata, false, false);
+	dp_aux_get_i2c_byte(dpInfo->auxPin, 0x50, rdata, true, false);
+
+	for (uint32 i = 0; i < sizeof(raw); i++) {
+		status_t result = dp_aux_get_i2c_byte(dpInfo->auxPin, 0x50, rdata++,
+			false, false);
+		if (result) {
+			ERROR("%s: error reading EDID data at index %" B_PRIu32 "\n",
+				__func__, i);
+			dp_aux_get_i2c_byte(dpInfo->auxPin, 0x50, &sdata, false, true);
+			return B_ERROR;
+		}
+	}
+	dp_aux_get_i2c_byte(dpInfo->auxPin, 0x50, &sdata, false, true);
+
+	if (raw.version.version != 1 || raw.version.revision > 4) {
+		ERROR("%s: EDID version or revision out of range\n", __func__);
+		return B_ERROR;
+	}
+
+	edid_decode(edid, &raw);
+
+	return B_OK;
+}
+
+
+status_t
+dp_get_pixel_size_for(color_space space, size_t *pixelChunk,
+	size_t *rowAlignment, size_t *pixelsPerChunk)
+{
+	status_t result = get_pixel_size_for(space, pixelChunk, NULL,
+		pixelsPerChunk);
+
+	if ((space == B_RGB32) || (space == B_RGBA32) || (space == B_RGB32_BIG)
+		|| (space == B_RGBA32_BIG)) {
+		*pixelChunk = 3;
+	}
+
+	return result;
+}
+
+
 void
 debug_dp_info()
 {
diff --git a/src/add-ons/accelerants/radeon_hd/displayport.h b/src/add-ons/accelerants/radeon_hd/displayport.h
index fa06dc6e741..ae484d081aa 100644
--- a/src/add-ons/accelerants/radeon_hd/displayport.h
+++ b/src/add-ons/accelerants/radeon_hd/displayport.h
@@ -1,9 +1,10 @@
 /*
- * Copyright 2011, Haiku, Inc. All Rights Reserved.
+ * Copyright 2011-2013, Haiku, Inc. All Rights Reserved.
  * Distributed under the terms of the MIT License.
  *
  * Authors:
  *		Alexander von Gluck IV, kallisti5@unixzen.com
+ *		Bill Randle, billr@neocat.org
  */
 #ifndef RADEON_HD_DISPLAYPORT_H
 #define RADEON_HD_DISPLAYPORT_H
@@ -30,9 +31,9 @@ int dp_aux_write(uint32 hwPin, uint16 address, uint8* send,
 int dp_aux_read(uint32 hwPin, uint16 address, uint8* recv,
 	int recvBytes, uint8 delay);
 status_t dp_aux_set_i2c_byte(uint32 hwPin, uint16 address,
-	uint8* data, bool end);
+	uint8* data, bool start, bool stop);
 status_t dp_aux_get_i2c_byte(uint32 hwPin, uint16 address,
-	uint8* data, bool end);
+	uint8* data, bool start, bool stop);
 
 uint32 dp_get_link_rate(uint32 connectorIndex, display_mode* mode);
 uint32 dp_get_lane_count(uint32 connectorIndex, display_mode* mode);
@@ -45,4 +46,9 @@ status_t dp_link_train_ce(uint32 connectorIndex);
 
 void debug_dp_info();
 
-#endif /* RADEON_HD_DISPLAYPORT_H */
+status_t dp_get_pixel_size_for(color_space space, size_t *pixelChunk,
+	size_t *rowAlignment, size_t *pixelsPerChunk);
+status_t ddc2_dp_read_edid1(uint32 connectorIndex, edid1_info *edid);
+
+
+#endif /* RADEON_HD_DISPLAYPORT_H */
\ No newline at end of file