drm/i915: Enable HDMI on DDI-E

DDI-E doesn't have the correspondent GMBUS pin.

We rely on VBT to tell us which one it being used instead.

The DVI/HDMI on shared port couldn't exist.

This patch isn't tested without hardware wchich has HDMI
on DDI-E.

v2: fix trailing whitespace
v3: MISSING_CASE take place of BUG()

Signed-off-by: Xiong Zhang <xiong.y.zhang@intel.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>

3 files changed, 47 insertions, 4 deletions

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 089459b39771..9b9bd2e34c13 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -1416,6 +1416,10 @@ enum modeset_restore {
 #define DP_AUX_C 0x20
 #define DP_AUX_D 0x30
 
+#define DDC_PIN_B  0x05
+#define DDC_PIN_C  0x04
+#define DDC_PIN_D  0x06
+
 struct ddi_vbt_port_info {
         /*
          * This is an index in the HDMI/DVI DDI buffer translation table.
@@ -1430,6 +1434,7 @@ struct ddi_vbt_port_info {
         uint8_t supports_dp:1;
 
         uint8_t alternate_aux_channel;
+        uint8_t alternate_ddc_pin;
 
         uint8_t dp_boost_level;
         uint8_t hdmi_boost_level;
diff --git a/drivers/gpu/drm/i915/intel_bios.c b/drivers/gpu/drm/i915/intel_bios.c
index be83b77aa018..313b5a73c6b4 100644
--- a/drivers/gpu/drm/i915/intel_bios.c
+++ b/drivers/gpu/drm/i915/intel_bios.c
@@ -905,7 +905,7 @@ static void parse_ddi_port(struct drm_i915_private *dev_priv, enum port port,
         uint8_t hdmi_level_shift;
         int i, j;
         bool is_dvi, is_hdmi, is_dp, is_edp, is_crt;
-        uint8_t aux_channel;
+        uint8_t aux_channel, ddc_pin;
         /* Each DDI port can have more than one value on the "DVO Port" field,
          * so look for all the possible values for each port and abort if more
          * than one is found. */
@@ -939,6 +939,7 @@ static void parse_ddi_port(struct drm_i915_private *dev_priv, enum port port,
                 return;
 
         aux_channel = child->raw[25];
+        ddc_pin = child->common.ddc_pin;
 
         is_dvi = child->common.device_type & DEVICE_TYPE_TMDS_DVI_SIGNALING;
         is_dp = child->common.device_type & DEVICE_TYPE_DISPLAYPORT_OUTPUT;
@@ -970,11 +971,27 @@ static void parse_ddi_port(struct drm_i915_private *dev_priv, enum port port,
                 DRM_DEBUG_KMS("Port %c is internal DP\n", port_name(port));
 
         if (is_dvi) {
-                if (child->common.ddc_pin == 0x05 && port != PORT_B)
+                if (port == PORT_E) {
+                        info->alternate_ddc_pin = ddc_pin;
+                        /* if DDIE share ddc pin with other port, then
+                         * dvi/hdmi couldn't exist on the shared port.
+                         * Otherwise they share the same ddc bin and system
+                         * couldn't communicate with them seperately. */
+                        if (ddc_pin == DDC_PIN_B) {
+                                dev_priv->vbt.ddi_port_info[PORT_B].supports_dvi = 0;
+                                dev_priv->vbt.ddi_port_info[PORT_B].supports_hdmi = 0;
+                        } else if (ddc_pin == DDC_PIN_C) {
+                                dev_priv->vbt.ddi_port_info[PORT_C].supports_dvi = 0;
+                                dev_priv->vbt.ddi_port_info[PORT_C].supports_hdmi = 0;
+                        } else if (ddc_pin == DDC_PIN_D) {
+                                dev_priv->vbt.ddi_port_info[PORT_D].supports_dvi = 0;
+                                dev_priv->vbt.ddi_port_info[PORT_D].supports_hdmi = 0;
+                        }
+                } else if (ddc_pin == DDC_PIN_B && port != PORT_B)
                         DRM_DEBUG_KMS("Unexpected DDC pin for port B\n");
-                if (child->common.ddc_pin == 0x04 && port != PORT_C)
+                else if (ddc_pin == DDC_PIN_C && port != PORT_C)
                         DRM_DEBUG_KMS("Unexpected DDC pin for port C\n");
-                if (child->common.ddc_pin == 0x06 && port != PORT_D)
+                else if (ddc_pin == DDC_PIN_D && port != PORT_D)
                         DRM_DEBUG_KMS("Unexpected DDC pin for port D\n");
         }
 
diff --git a/drivers/gpu/drm/i915/intel_hdmi.c b/drivers/gpu/drm/i915/intel_hdmi.c
index 51cbea8247fe..dcd336bcdfe7 100644
--- a/drivers/gpu/drm/i915/intel_hdmi.c
+++ b/drivers/gpu/drm/i915/intel_hdmi.c
@@ -1958,6 +1958,7 @@ void intel_hdmi_init_connector(struct intel_digital_port *intel_dig_port,
         struct drm_device *dev = intel_encoder->base.dev;
         struct drm_i915_private *dev_priv = dev->dev_private;
         enum port port = intel_dig_port->port;
+        uint8_t alternate_ddc_pin;
 
         drm_connector_init(dev, connector, &intel_hdmi_connector_funcs,
                            DRM_MODE_CONNECTOR_HDMIA);
@@ -1991,6 +1992,26 @@ void intel_hdmi_init_connector(struct intel_digital_port *intel_dig_port,
                         intel_hdmi->ddc_bus = GMBUS_PIN_DPD;
                 intel_encoder->hpd_pin = HPD_PORT_D;
                 break;
+        case PORT_E:
+                /* On SKL PORT E doesn't have seperate GMBUS pin
+                 *  We rely on VBT to set a proper alternate GMBUS pin. */
+                alternate_ddc_pin =
+                        dev_priv->vbt.ddi_port_info[PORT_E].alternate_ddc_pin;
+                switch (alternate_ddc_pin) {
+                case DDC_PIN_B:
+                        intel_hdmi->ddc_bus = GMBUS_PIN_DPB;
+                        break;
+                case DDC_PIN_C:
+                        intel_hdmi->ddc_bus = GMBUS_PIN_DPC;
+                        break;
+                case DDC_PIN_D:
+                        intel_hdmi->ddc_bus = GMBUS_PIN_DPD;
+                        break;
+                default:
+                        MISSING_CASE(alternate_ddc_pin);
+                }
+                intel_encoder->hpd_pin = HPD_PORT_E;
+                break;
         case PORT_A:
                 intel_encoder->hpd_pin = HPD_PORT_A;
                 /* Internal port only for eDP. */