Patch "drm/i915: always update ELD connector type after get modes" has been added to the 4.13-stable tree

This is a note to let you know that I've just added the patch titled

drm/i915: always update ELD connector type after get modes

to the 4.13-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
drm-i915-always-update-eld-connector-type-after-get-modes.patch
and it can be found in the queue-4.13 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Jani Nikula <[email protected]>
Date: Tue, 19 Sep 2017 18:38:13 +0300
Subject: drm/i915: always update ELD connector type after get modes
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From: Jani Nikula <[email protected]>

commit 2d8f63297b9f0b430c96329893667c0bfdcbd47e upstream.

drm_edid_to_eld() initializes the connector ELD to zero, overwriting the ELD connector type initialized in intel_audio_codec_enable(). If userspace does getconnector and thus get_modes after modeset, a subsequent audio component i915_audio_component_get_eld() call will receive an ELD without the connector type properly set. It's fine for HDMI, but screws up audio for DP.

Always set the ELD connector type at intel_connector_update_modes() based on the connector type. We can drop the connector type update from intel_audio_codec_enable().

Credits to Joseph Nuzman <[email protected]> for figuring this out.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=101583

---
 drivers/gpu/drm/i915/intel_audio.c |    5 -----
 drivers/gpu/drm/i915/intel_modes.c |   17 +++++++++++++++++
 2 files changed, 17 insertions(+), 5 deletions(-)

@@ -606,11 +606,6 @@ void intel_audio_codec_enable(struct int
 			 connector->encoder->base.id,
 			 connector->encoder->name);
 
-	/* ELD Conn_Type */
-	connector->eld[5] &= ~(3 << 2);
-	if (intel_crtc_has_dp_encoder(crtc_state))
-		connector->eld[5] |= (1 << 2);
-
 	connector->eld[6] = drm_av_sync_delay(connector, adjusted_mode) / 2;
 
 	if (dev_priv->display.audio_codec_enable)

@@ -30,6 +30,21 @@
 #include "intel_drv.h"
 #include "i915_drv.h"
 
+static void intel_connector_update_eld_conn_type(struct drm_connector *connector)
+{
+	u8 conn_type;
+
+	if (connector->connector_type == DRM_MODE_CONNECTOR_DisplayPort ||
+	    connector->connector_type == DRM_MODE_CONNECTOR_eDP) {
+		conn_type = DRM_ELD_CONN_TYPE_DP;
+	} else {
+		conn_type = DRM_ELD_CONN_TYPE_HDMI;
+	}
+
+	connector->eld[DRM_ELD_SAD_COUNT_CONN_TYPE] &= ~DRM_ELD_CONN_TYPE_MASK;
+	connector->eld[DRM_ELD_SAD_COUNT_CONN_TYPE] |= conn_type;
+}
+
 /**
  * intel_connector_update_modes - update connector from edid
  * @connector: DRM connector device to use

@@ -44,6 +59,8 @@ int intel_connector_update_modes(struct
 	ret = drm_add_edid_modes(connector, edid);
 	drm_edid_to_eld(connector, edid);
 
+	intel_connector_update_eld_conn_type(connector);
+
 	return ret;
 }
 

Patches currently in stable-queue which might be from [email protected] are

queue-4.13/drm-i915-always-update-eld-connector-type-after-get-modes.patch queue-4.13/drm-i915-bios-ignore-hdmi-on-port-a.patch