[PATCH 3/3 v3] drm: bridge/dw-hdmi: Move edid reading to .detect() callback

[Jose Abreu]

When running HDMI compliance tests we noticed that sometimes
the edid changes but the get_modes() function is not called
so the edid is not updated. Moving the edid reading to the
detect() callback ensures that the edid is correctly updated
after an hotplug.

Signed-off-by: Jose Abreu <joabreu@xxxxxxxxxxxx>
Cc: Carlos Palminha <palminha@xxxxxxxxxxxx>
Cc: Archit Taneja <architt@xxxxxxxxxxxxxx>
Cc: David Airlie <airlied@xxxxxxxx>
Cc: Russell King <rmk+kernel@xxxxxxxxxxxxxxxx>
Cc: Fabio Estevam <fabio.estevam@xxxxxxxxxxxxx>
Cc: Daniel Vetter <daniel.vetter@xxxxxxxx>
Cc: Takashi Iwai <tiwai@xxxxxxx>
Cc: Vladimir Zapolskiy <vladimir_zapolskiy@xxxxxxxxxx>
Cc: Thierry Reding <treding@xxxxxxxxxx>
Cc: dri-devel@xxxxxxxxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
---

This patch was only introduced in v3.

 drivers/gpu/drm/bridge/dw-hdmi.c | 67 +++++++++++++++++++++++-----------------
 1 file changed, 38 insertions(+), 29 deletions(-)

diff --git a/drivers/gpu/drm/bridge/dw-hdmi.c b/drivers/gpu/drm/bridge/dw-hdmi.c
index 9122a20..c795888 100644
--- a/drivers/gpu/drm/bridge/dw-hdmi.c
+++ b/drivers/gpu/drm/bridge/dw-hdmi.c
@@ -31,8 +31,6 @@
 #include "dw-hdmi.h"
 #include "dw-hdmi-audio.h"
 
-#define HDMI_EDID_LEN		512
-
 #define RGB			0
 #define YCBCR444		1
 #define YCBCR422_16BITS		2
@@ -117,7 +115,7 @@ struct dw_hdmi {
 
 	int vic;
 
-	u8 edid[HDMI_EDID_LEN];
+	struct edid *edid;
 	bool cable_plugin;
 
 	bool phy_enabled;
@@ -1457,6 +1455,7 @@ dw_hdmi_connector_detect(struct drm_connector *connector, bool force)
 {
 	struct dw_hdmi *hdmi = container_of(connector, struct dw_hdmi,
 					     connector);
+	bool connected;
 
 	mutex_lock(&hdmi->mutex);
 	hdmi->force = DRM_FORCE_UNSPECIFIED;
@@ -1464,7 +1463,40 @@ dw_hdmi_connector_detect(struct drm_connector *connector, bool force)
 	dw_hdmi_update_phy_mask(hdmi);
 	mutex_unlock(&hdmi->mutex);
 
-	return hdmi_readb(hdmi, HDMI_PHY_STAT0) & HDMI_PHY_HPD ?
+	connected = hdmi_readb(hdmi, HDMI_PHY_STAT0) & HDMI_PHY_HPD;
+
+	if (connected && hdmi->ddc) {
+		if (hdmi->edid) {
+			drm_mode_connector_update_edid_property(connector,
+					NULL);
+			kfree(hdmi->edid);
+			hdmi->edid = NULL;
+		}
+
+		hdmi->edid = drm_get_edid(connector, hdmi->ddc);
+		if (hdmi->edid) {
+			dev_dbg(hdmi->dev, "got edid: width[%d] x height[%d]\n",
+					hdmi->edid->width_cm,
+					hdmi->edid->height_cm);
+			drm_mode_connector_update_edid_property(connector,
+					hdmi->edid);
+			drm_edid_to_eld(connector, hdmi->edid);
+
+			hdmi->sink_is_hdmi =
+				drm_detect_hdmi_monitor(hdmi->edid);
+			hdmi->sink_has_audio =
+				drm_detect_monitor_audio(hdmi->edid);
+			hdmi->sink_supports_ai =
+				connector->eld[5] & (0x1 << 1);
+		} else {
+			dev_dbg(hdmi->dev, "failed to get edid\n");
+			hdmi->sink_is_hdmi = false;
+			hdmi->sink_has_audio = false;
+			hdmi->sink_supports_ai = false;
+		}
+	}
+
+	return connected ?
 		connector_status_connected : connector_status_disconnected;
 }
 
@@ -1472,33 +1504,10 @@ static int dw_hdmi_connector_get_modes(struct drm_connector *connector)
 {
 	struct dw_hdmi *hdmi = container_of(connector, struct dw_hdmi,
 					     connector);
-	struct edid *edid;
 	int ret = 0;
 
-	if (!hdmi->ddc)
-		return 0;
-
-	edid = drm_get_edid(connector, hdmi->ddc);
-	if (edid) {
-		dev_dbg(hdmi->dev, "got edid: width[%d] x height[%d]\n",
-			edid->width_cm, edid->height_cm);
-
-		hdmi->sink_is_hdmi = drm_detect_hdmi_monitor(edid);
-		hdmi->sink_has_audio = drm_detect_monitor_audio(edid);
-		drm_mode_connector_update_edid_property(connector, edid);
-		ret = drm_add_edid_modes(connector, edid);
-		/* Store the ELD */
-		drm_edid_to_eld(connector, edid);
-		kfree(edid);
-
-		hdmi->sink_supports_ai = connector->eld[5] & (0x1 << 1);
-	} else {
-		dev_dbg(hdmi->dev, "failed to get edid\n");
-		hdmi->sink_is_hdmi = false;
-		hdmi->sink_has_audio = false;
-		hdmi->sink_supports_ai = false;
-	}
-
+	if (hdmi->edid)
+		ret = drm_add_edid_modes(connector, hdmi->edid);
 	return ret;
 }
 
-- 
2.1.4