1 files changed, 52 insertions, 3 deletions

diff --git a/drivers/gpu/drm/i915/intel_hdmi.c b/drivers/gpu/drm/i915/intel_hdmi.c
index c33451aec1bd..f04dbbe7d400 100644
--- a/drivers/gpu/drm/i915/intel_hdmi.c
+++ b/drivers/gpu/drm/i915/intel_hdmi.c
@@ -82,7 +82,7 @@ static void intel_hdmi_dpms(struct drm_encoder *encoder, int mode)
         /* HW workaround, need to toggle enable bit off and on for 12bpc, but
          * we do this anyway which shows more stable in testing.
          */
-        if (IS_IGDNG(dev)) {
+        if (IS_IRONLAKE(dev)) {
                 I915_WRITE(hdmi_priv->sdvox_reg, temp & ~SDVO_ENABLE);
                 POSTING_READ(hdmi_priv->sdvox_reg);
         }
@@ -99,7 +99,7 @@ static void intel_hdmi_dpms(struct drm_encoder *encoder, int mode)
         /* HW workaround, need to write this twice for issue that may result
          * in first write getting masked.
          */
-        if (IS_IGDNG(dev)) {
+        if (IS_IRONLAKE(dev)) {
                 I915_WRITE(hdmi_priv->sdvox_reg, temp);
                 POSTING_READ(hdmi_priv->sdvox_reg);
         }
@@ -225,7 +225,52 @@ static const struct drm_encoder_funcs intel_hdmi_enc_funcs = {
         .destroy = intel_hdmi_enc_destroy,
 };
 
-
+/*
+ * Enumerate the child dev array parsed from VBT to check whether
+ * the given HDMI is present.
+ * If it is present, return 1.
+ * If it is not present, return false.
+ * If no child dev is parsed from VBT, it assumes that the given
+ * HDMI is present.
+ */
+static int hdmi_is_present_in_vbt(struct drm_device *dev, int hdmi_reg)
+{
+        struct drm_i915_private *dev_priv = dev->dev_private;
+        struct child_device_config *p_child;
+        int i, hdmi_port, ret;
+
+        if (!dev_priv->child_dev_num)
+                return 1;
+
+        if (hdmi_reg == SDVOB)
+                hdmi_port = DVO_B;
+        else if (hdmi_reg == SDVOC)
+                hdmi_port = DVO_C;
+        else if (hdmi_reg == HDMIB)
+                hdmi_port = DVO_B;
+        else if (hdmi_reg == HDMIC)
+                hdmi_port = DVO_C;
+        else if (hdmi_reg == HDMID)
+                hdmi_port = DVO_D;
+        else
+                return 0;
+
+        ret = 0;
+        for (i = 0; i < dev_priv->child_dev_num; i++) {
+                p_child = dev_priv->child_dev + i;
+                /*
+                 * If the device type is not HDMI, continue.
+                 */
+                if (p_child->device_type != DEVICE_TYPE_HDMI)
+                        continue;
+                /* Find the HDMI port */
+                if (p_child->dvo_port == hdmi_port) {
+                        ret = 1;
+                        break;
+                }
+        }
+        return ret;
+}
 void intel_hdmi_init(struct drm_device *dev, int sdvox_reg)
 {
         struct drm_i915_private *dev_priv = dev->dev_private;
@@ -233,6 +278,10 @@ void intel_hdmi_init(struct drm_device *dev, int sdvox_reg)
         struct intel_output *intel_output;
         struct intel_hdmi_priv *hdmi_priv;
 
+        if (!hdmi_is_present_in_vbt(dev, sdvox_reg)) {
+                DRM_DEBUG_KMS("HDMI is not present. Ignored it \n");
+                return;
+        }
         intel_output = kcalloc(sizeof(struct intel_output) +
                                sizeof(struct intel_hdmi_priv), 1, GFP_KERNEL);
         if (!intel_output)