drm/i915: add support for DDI-controlled digital outputs

Those are driven by DDIs on Haswell architecture, so we need to keep track
of which DDI is being used on each output.
Reviewed-by: NJesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: NEugeni Dodonov <eugeni.dodonov@intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/intel_hdmi.c

@@ -41,6 +41,7 @@ struct intel_hdmi {
 	struct intel_encoder base;
 	u32 sdvox_reg;
 	int ddc_bus;
+	int ddi_port;
 	uint32_t color_range;
 	bool has_hdmi_sink;
 	bool has_audio;
@@ -661,6 +662,24 @@ void intel_hdmi_init(struct drm_device *dev, int sdvox_reg)
 		intel_encoder->clone_mask = (1 << INTEL_HDMIF_CLONE_BIT);
 		intel_hdmi->ddc_bus = GMBUS_PORT_DPD;
 		dev_priv->hotplug_supported_mask |= HDMID_HOTPLUG_INT_STATUS;
+	} else if (sdvox_reg == DDI_BUF_CTL(PORT_B)) {
+		DRM_DEBUG_DRIVER("LPT: detected output on DDI B\n");
+		intel_encoder->clone_mask = (1 << INTEL_HDMIB_CLONE_BIT);
+		intel_hdmi->ddc_bus = GMBUS_PORT_DPB;
+		intel_hdmi->ddi_port = PORT_B;
+		dev_priv->hotplug_supported_mask |= HDMIB_HOTPLUG_INT_STATUS;
+	} else if (sdvox_reg == DDI_BUF_CTL(PORT_C)) {
+		DRM_DEBUG_DRIVER("LPT: detected output on DDI C\n");
+		intel_encoder->clone_mask = (1 << INTEL_HDMIC_CLONE_BIT);
+		intel_hdmi->ddc_bus = GMBUS_PORT_DPC;
+		intel_hdmi->ddi_port = PORT_C;
+		dev_priv->hotplug_supported_mask |= HDMIC_HOTPLUG_INT_STATUS;
+	} else if (sdvox_reg == DDI_BUF_CTL(PORT_D)) {
+		DRM_DEBUG_DRIVER("LPT: detected output on DDI D\n");
+		intel_encoder->clone_mask = (1 << INTEL_HDMID_CLONE_BIT);
+		intel_hdmi->ddc_bus = GMBUS_PORT_DPD;
+		intel_hdmi->ddi_port = PORT_D;
+		dev_priv->hotplug_supported_mask |= HDMID_HOTPLUG_INT_STATUS;
 	} else {
 		/* If we got an unknown sdvox_reg, things are pretty much broken
 		 * in a way that we should let the kernel know about it */