drm/radeon/kms: fix connector edid handling

Based partly on a patch from
Christian Koenig <deathsimple@vodafone.de>

- fix several memory leaks in radeon_connector->edid handling
- store edid in radeon_connector->edid in detect() or get_modes()
- switch hdmi detect code to use radeon_connector->edid
- add support for oem boards multiple connectors that share
a ddc line.
- short circuit lvds_detect() if have a stored edid

Signed-off-by: Alex Deucher <alexdeucher@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
diff --git a/drivers/gpu/drm/radeon/radeon_connectors.c b/drivers/gpu/drm/radeon/radeon_connectors.c
index 729207a..5b6067a 100644
--- a/drivers/gpu/drm/radeon/radeon_connectors.c
+++ b/drivers/gpu/drm/radeon/radeon_connectors.c
@@ -400,7 +400,6 @@
 	struct radeon_connector *radeon_connector = to_radeon_connector(connector);
 	struct drm_encoder *encoder = radeon_best_single_encoder(connector);
 	enum drm_connector_status ret = connector_status_disconnected;
-	bool dret;
 
 	if (encoder) {
 		struct radeon_encoder *radeon_encoder = to_radeon_encoder(encoder);
@@ -413,12 +412,17 @@
 	}
 
 	/* check for edid as well */
-	if (radeon_connector->ddc_bus) {
-		radeon_i2c_do_lock(radeon_connector, 1);
-		dret = radeon_ddc_probe(radeon_connector);
-		radeon_i2c_do_lock(radeon_connector, 0);
-		if (dret)
-			ret = connector_status_connected;
+	if (radeon_connector->edid)
+		ret = connector_status_connected;
+	else {
+		if (radeon_connector->ddc_bus) {
+			radeon_i2c_do_lock(radeon_connector, 1);
+			radeon_connector->edid = drm_get_edid(&radeon_connector->base,
+							      &radeon_connector->ddc_bus->adapter);
+			radeon_i2c_do_lock(radeon_connector, 0);
+			if (radeon_connector->edid)
+				ret = connector_status_connected;
+		}
 	}
 	/* check acpi lid status ??? */
 
@@ -432,6 +436,8 @@
 
 	if (radeon_connector->ddc_bus)
 		radeon_i2c_destroy(radeon_connector->ddc_bus);
+	if (radeon_connector->edid)
+		kfree(radeon_connector->edid);
 	kfree(radeon_connector->con_priv);
 	drm_sysfs_connector_remove(connector);
 	drm_connector_cleanup(connector);
@@ -519,9 +525,32 @@
 	radeon_i2c_do_lock(radeon_connector, 1);
 	dret = radeon_ddc_probe(radeon_connector);
 	radeon_i2c_do_lock(radeon_connector, 0);
-	if (dret)
-		ret = connector_status_connected;
-	else {
+	if (dret) {
+		if (radeon_connector->edid) {
+			kfree(radeon_connector->edid);
+			radeon_connector->edid = NULL;
+		}
+		radeon_i2c_do_lock(radeon_connector, 1);
+		radeon_connector->edid = drm_get_edid(&radeon_connector->base, &radeon_connector->ddc_bus->adapter);
+		radeon_i2c_do_lock(radeon_connector, 0);
+
+		if (!radeon_connector->edid) {
+			DRM_ERROR("DDC responded but not EDID found for %s\n",
+				  drm_get_connector_name(connector));
+		} else {
+			radeon_connector->use_digital = !!(radeon_connector->edid->input & DRM_EDID_INPUT_DIGITAL);
+
+			/* some oems have boards with separate digital and analog connectors
+			 * with a shared ddc line (often vga + hdmi)
+			 */
+			if (radeon_connector->use_digital && radeon_connector->shared_ddc) {
+				kfree(radeon_connector->edid);
+				radeon_connector->edid = NULL;
+				ret = connector_status_disconnected;
+			} else
+				ret = connector_status_connected;
+		}
+	} else {
 		if (radeon_connector->dac_load_detect) {
 			encoder_funcs = encoder->helper_private;
 			ret = encoder_funcs->detect(encoder, connector);
@@ -649,6 +678,10 @@
 	dret = radeon_ddc_probe(radeon_connector);
 	radeon_i2c_do_lock(radeon_connector, 0);
 	if (dret) {
+		if (radeon_connector->edid) {
+			kfree(radeon_connector->edid);
+			radeon_connector->edid = NULL;
+		}
 		radeon_i2c_do_lock(radeon_connector, 1);
 		radeon_connector->edid = drm_get_edid(&radeon_connector->base, &radeon_connector->ddc_bus->adapter);
 		radeon_i2c_do_lock(radeon_connector, 0);
@@ -659,10 +692,15 @@
 		} else {
 			radeon_connector->use_digital = !!(radeon_connector->edid->input & DRM_EDID_INPUT_DIGITAL);
 
-			/* if this isn't a digital monitor
-			   then we need to make sure we don't have any
-			   TV conflicts */
-			ret = connector_status_connected;
+			/* some oems have boards with separate digital and analog connectors
+			 * with a shared ddc line (often vga + hdmi)
+			 */
+			if ((!radeon_connector->use_digital) && radeon_connector->shared_ddc) {
+				kfree(radeon_connector->edid);
+				radeon_connector->edid = NULL;
+				ret = connector_status_disconnected;
+			} else
+				ret = connector_status_connected;
 		}
 	}
 
@@ -787,6 +825,7 @@
 	struct radeon_connector *radeon_connector;
 	struct radeon_connector_atom_dig *radeon_dig_connector;
 	uint32_t subpixel_order = SubPixelNone;
+	bool shared_ddc = false;
 	int ret;
 
 	/* fixme - tv/cv/din */
@@ -800,6 +839,13 @@
 			radeon_connector->devices |= supported_device;
 			return;
 		}
+		if (radeon_connector->ddc_bus && i2c_bus->valid) {
+			if (memcmp(&radeon_connector->ddc_bus->rec, i2c_bus,
+				    sizeof(struct radeon_i2c_bus_rec)) == 0) {
+				radeon_connector->shared_ddc = true;
+				shared_ddc = true;
+			}
+		}
 	}
 
 	radeon_connector = kzalloc(sizeof(struct radeon_connector), GFP_KERNEL);
@@ -810,6 +856,7 @@
 
 	radeon_connector->connector_id = connector_id;
 	radeon_connector->devices = supported_device;
+	radeon_connector->shared_ddc = shared_ddc;
 	switch (connector_type) {
 	case DRM_MODE_CONNECTOR_VGA:
 		drm_connector_init(dev, &radeon_connector->base, &radeon_vga_connector_funcs, connector_type);
diff --git a/drivers/gpu/drm/radeon/radeon_display.c b/drivers/gpu/drm/radeon/radeon_display.c
index a20bf43..c85df4a 100644
--- a/drivers/gpu/drm/radeon/radeon_display.c
+++ b/drivers/gpu/drm/radeon/radeon_display.c
@@ -334,27 +334,19 @@
 
 int radeon_ddc_get_modes(struct radeon_connector *radeon_connector)
 {
-	struct edid *edid;
 	int ret = 0;
 
 	if (!radeon_connector->ddc_bus)
 		return -1;
 	if (!radeon_connector->edid) {
 		radeon_i2c_do_lock(radeon_connector, 1);
-		edid = drm_get_edid(&radeon_connector->base, &radeon_connector->ddc_bus->adapter);
+		radeon_connector->edid = drm_get_edid(&radeon_connector->base, &radeon_connector->ddc_bus->adapter);
 		radeon_i2c_do_lock(radeon_connector, 0);
-	} else
-		edid = radeon_connector->edid;
+	}
 
-	if (edid) {
-		/* update digital bits here */
-		if (edid->input & DRM_EDID_INPUT_DIGITAL)
-			radeon_connector->use_digital = 1;
-		else
-			radeon_connector->use_digital = 0;
-		drm_mode_connector_update_edid_property(&radeon_connector->base, edid);
-		ret = drm_add_edid_modes(&radeon_connector->base, edid);
-		kfree(edid);
+	if (radeon_connector->edid) {
+		drm_mode_connector_update_edid_property(&radeon_connector->base, radeon_connector->edid);
+		ret = drm_add_edid_modes(&radeon_connector->base, radeon_connector->edid);
 		return ret;
 	}
 	drm_mode_connector_update_edid_property(&radeon_connector->base, NULL);
diff --git a/drivers/gpu/drm/radeon/radeon_encoders.c b/drivers/gpu/drm/radeon/radeon_encoders.c
index 6cdef27..b70440e 100644
--- a/drivers/gpu/drm/radeon/radeon_encoders.c
+++ b/drivers/gpu/drm/radeon/radeon_encoders.c
@@ -449,7 +449,7 @@
 		case 1:
 			args.v1.ucMisc = 0;
 			args.v1.ucAction = action;
-			if (drm_detect_hdmi_monitor((struct edid *)connector->edid_blob_ptr))
+			if (drm_detect_hdmi_monitor(radeon_connector->edid))
 				args.v1.ucMisc |= PANEL_ENCODER_MISC_HDMI_TYPE;
 			args.v1.usPixelClock = cpu_to_le16(radeon_encoder->pixel_clock / 10);
 			if (radeon_encoder->devices & (ATOM_DEVICE_LCD_SUPPORT)) {
@@ -474,7 +474,7 @@
 				if (dig->coherent_mode)
 					args.v2.ucMisc |= PANEL_ENCODER_MISC_COHERENT;
 			}
-			if (drm_detect_hdmi_monitor((struct edid *)connector->edid_blob_ptr))
+			if (drm_detect_hdmi_monitor(radeon_connector->edid))
 				args.v2.ucMisc |= PANEL_ENCODER_MISC_HDMI_TYPE;
 			args.v2.usPixelClock = cpu_to_le16(radeon_encoder->pixel_clock / 10);
 			args.v2.ucTruncate = 0;
@@ -532,7 +532,7 @@
 	switch (connector->connector_type) {
 	case DRM_MODE_CONNECTOR_DVII:
 	case DRM_MODE_CONNECTOR_HDMIB: /* HDMI-B is basically DL-DVI; analog works fine */
-		if (drm_detect_hdmi_monitor((struct edid *)connector->edid_blob_ptr))
+		if (drm_detect_hdmi_monitor(radeon_connector->edid))
 			return ATOM_ENCODER_MODE_HDMI;
 		else if (radeon_connector->use_digital)
 			return ATOM_ENCODER_MODE_DVI;
@@ -542,7 +542,7 @@
 	case DRM_MODE_CONNECTOR_DVID:
 	case DRM_MODE_CONNECTOR_HDMIA:
 	default:
-		if (drm_detect_hdmi_monitor((struct edid *)connector->edid_blob_ptr))
+		if (drm_detect_hdmi_monitor(radeon_connector->edid))
 			return ATOM_ENCODER_MODE_HDMI;
 		else
 			return ATOM_ENCODER_MODE_DVI;
@@ -554,7 +554,7 @@
 		/*if (radeon_output->MonType == MT_DP)
 		  return ATOM_ENCODER_MODE_DP;
 		  else*/
-		if (drm_detect_hdmi_monitor((struct edid *)connector->edid_blob_ptr))
+		if (drm_detect_hdmi_monitor(radeon_connector->edid))
 			return ATOM_ENCODER_MODE_HDMI;
 		else
 			return ATOM_ENCODER_MODE_DVI;
diff --git a/drivers/gpu/drm/radeon/radeon_mode.h b/drivers/gpu/drm/radeon/radeon_mode.h
index 3d2631b..b6868fb 100644
--- a/drivers/gpu/drm/radeon/radeon_mode.h
+++ b/drivers/gpu/drm/radeon/radeon_mode.h
@@ -297,6 +297,8 @@
 	uint32_t connector_id;
 	uint32_t devices;
 	struct radeon_i2c_chan *ddc_bus;
+	/* some systems have a an hdmi and vga port with a shared ddc line */
+	bool shared_ddc;
 	bool use_digital;
 	/* we need to mind the EDID between detect
 	   and get modes due to analog/digital/tvencoder */