drm/i915: sync hdmi detection by hdmi identifier with 2D

Currently we detect HDMI monitor by hardware detection, but if an HDMI-DVI
adapter is used to connect a DVI monitor, hardware detection will incorrectly
take monitor as HDMI. HDMI spec says any device containing IEEE registration
identifier will be treated as HDMI device.  The patch intends to detect HDMI
monitor by drm_detect_hdmi_monitor function which follows that rule.

Signed-off-by: Ma Ling <ling.ma@intel.com>
Signed-off-by: Eric Anholt <eric@anholt.net>

1 files changed, 20 insertions, 2 deletions

diff --git a/drivers/gpu/drm/i915/intel_sdvo.c b/drivers/gpu/drm/i915/intel_sdvo.c
index 7b31f55f55c8..9913651c1e17 100644
--- a/drivers/gpu/drm/i915/intel_sdvo.c
+++ b/drivers/gpu/drm/i915/intel_sdvo.c
@@ -1357,6 +1357,23 @@ void intel_sdvo_set_hotplug(struct drm_connector *connector, int on)
         intel_sdvo_read_response(intel_output, &response, 2);
 }
 
+static void
+intel_sdvo_hdmi_sink_detect(struct drm_connector *connector)
+{
+        struct intel_output *intel_output = to_intel_output(connector);
+        struct intel_sdvo_priv *sdvo_priv = intel_output->dev_priv;
+        struct edid *edid = NULL;
+
+        intel_sdvo_set_control_bus_switch(intel_output, sdvo_priv->ddc_bus);
+        edid = drm_get_edid(&intel_output->base,
+                            &intel_output->ddc_bus->adapter);
+        if (edid != NULL) {
+                sdvo_priv->is_hdmi = drm_detect_hdmi_monitor(edid);
+                kfree(edid);
+                intel_output->base.display_info.raw_edid = NULL;
+        }
+}
+
 static enum drm_connector_status intel_sdvo_detect(struct drm_connector *connector)
 {
         u8 response[2];
@@ -1371,9 +1388,10 @@ static enum drm_connector_status intel_sdvo_detect(struct drm_connector *connect
         if (status != SDVO_CMD_STATUS_SUCCESS)
                 return connector_status_unknown;
 
-        if ((response[0] != 0) || (response[1] != 0))
+        if ((response[0] != 0) || (response[1] != 0)) {
+                intel_sdvo_hdmi_sink_detect(connector);
                 return connector_status_connected;
-        else
+        } else
                 return connector_status_disconnected;
 }