1 files changed, 48 insertions, 14 deletions

diff --git a/drivers/gpu/drm/i915/intel_bios.c b/drivers/gpu/drm/i915/intel_bios.c
index 4867f4cc0938..aff4a113cda3 100644
--- a/drivers/gpu/drm/i915/intel_bios.c
+++ b/drivers/gpu/drm/i915/intel_bios.c
@@ -287,6 +287,9 @@ parse_lfp_backlight(struct drm_i915_private *dev_priv, struct bdb_header *bdb)
         const struct bdb_lfp_backlight_data *backlight_data;
         const struct bdb_lfp_backlight_data_entry *entry;
 
+        /* Err to enabling backlight if no backlight block. */
+        dev_priv->vbt.backlight.present = true;
+
         backlight_data = find_section(bdb, BDB_LVDS_BACKLIGHT);
         if (!backlight_data)
                 return;
@@ -299,6 +302,13 @@ parse_lfp_backlight(struct drm_i915_private *dev_priv, struct bdb_header *bdb)
 
         entry = &backlight_data->data[panel_type];
 
+        dev_priv->vbt.backlight.present = entry->type == BDB_BACKLIGHT_TYPE_PWM;
+        if (!dev_priv->vbt.backlight.present) {
+                DRM_DEBUG_KMS("PWM backlight not present in VBT (type %u)\n",
+                              entry->type);
+                return;
+        }
+
         dev_priv->vbt.backlight.pwm_freq_hz = entry->pwm_freq_hz;
         dev_priv->vbt.backlight.active_low_pwm = entry->active_low_pwm;
         DRM_DEBUG_KMS("VBT backlight PWM modulation frequency %u Hz, "
@@ -550,47 +560,71 @@ parse_edp(struct drm_i915_private *dev_priv, struct bdb_header *bdb)
 
         dev_priv->vbt.edp_pps = *edp_pps;
 
-        dev_priv->vbt.edp_rate = edp_link_params->rate ? DP_LINK_BW_2_7 :
-                DP_LINK_BW_1_62;
+        switch (edp_link_params->rate) {
+        case EDP_RATE_1_62:
+                dev_priv->vbt.edp_rate = DP_LINK_BW_1_62;
+                break;
+        case EDP_RATE_2_7:
+                dev_priv->vbt.edp_rate = DP_LINK_BW_2_7;
+                break;
+        default:
+                DRM_DEBUG_KMS("VBT has unknown eDP link rate value %u\n",
+                              edp_link_params->rate);
+                break;
+        }
+
         switch (edp_link_params->lanes) {
-        case 0:
+        case EDP_LANE_1:
                 dev_priv->vbt.edp_lanes = 1;
                 break;
-        case 1:
+        case EDP_LANE_2:
                 dev_priv->vbt.edp_lanes = 2;
                 break;
-        case 3:
-        default:
+        case EDP_LANE_4:
                 dev_priv->vbt.edp_lanes = 4;
                 break;
+        default:
+                DRM_DEBUG_KMS("VBT has unknown eDP lane count value %u\n",
+                              edp_link_params->lanes);
+                break;
         }
+
         switch (edp_link_params->preemphasis) {
-        case 0:
+        case EDP_PREEMPHASIS_NONE:
                 dev_priv->vbt.edp_preemphasis = DP_TRAIN_PRE_EMPHASIS_0;
                 break;
-        case 1:
+        case EDP_PREEMPHASIS_3_5dB:
                 dev_priv->vbt.edp_preemphasis = DP_TRAIN_PRE_EMPHASIS_3_5;
                 break;
-        case 2:
+        case EDP_PREEMPHASIS_6dB:
                 dev_priv->vbt.edp_preemphasis = DP_TRAIN_PRE_EMPHASIS_6;
                 break;
-        case 3:
+        case EDP_PREEMPHASIS_9_5dB:
                 dev_priv->vbt.edp_preemphasis = DP_TRAIN_PRE_EMPHASIS_9_5;
                 break;
+        default:
+                DRM_DEBUG_KMS("VBT has unknown eDP pre-emphasis value %u\n",
+                              edp_link_params->preemphasis);
+                break;
         }
+
         switch (edp_link_params->vswing) {
-        case 0:
+        case EDP_VSWING_0_4V:
                 dev_priv->vbt.edp_vswing = DP_TRAIN_VOLTAGE_SWING_400;
                 break;
-        case 1:
+        case EDP_VSWING_0_6V:
                 dev_priv->vbt.edp_vswing = DP_TRAIN_VOLTAGE_SWING_600;
                 break;
-        case 2:
+        case EDP_VSWING_0_8V:
                 dev_priv->vbt.edp_vswing = DP_TRAIN_VOLTAGE_SWING_800;
                 break;
-        case 3:
+        case EDP_VSWING_1_2V:
                 dev_priv->vbt.edp_vswing = DP_TRAIN_VOLTAGE_SWING_1200;
                 break;
+        default:
+                DRM_DEBUG_KMS("VBT has unknown eDP voltage swing value %u\n",
+                              edp_link_params->vswing);
+                break;
         }
 }