drm/i915: don't init DP or HDMI when not supported by DDI port

There's no reason to init a DP connector if the encoder just supports
HDMI: we'll just waste hundreds and hundreds of cycles trying to do DP
AUX transactions to detect if there's something there. Same goes for a
DP connector that doesn't support HDMI, but I'm not sure these
actually exist.

v2: - Use bit fields
    - Remove useless identation level
    - Replace DRM_ERROR with DRM_DEBUG_KMS

Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@gmail.com> (v1)
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/intel_bios.c b/drivers/gpu/drm/i915/intel_bios.c
index 7ce1c3c..0492b6f 100644
--- a/drivers/gpu/drm/i915/intel_bios.c
+++ b/drivers/gpu/drm/i915/intel_bios.c
@@ -632,6 +632,10 @@
 	is_hdmi = is_dvi && (child->common.device_type & (1 << 11)) == 0;
 	is_edp = is_dp && (child->common.device_type & (1 << 12));
 
+	info->supports_dvi = is_dvi;
+	info->supports_hdmi = is_hdmi;
+	info->supports_dp = is_dp;
+
 	DRM_DEBUG_KMS("Port %c VBT info: DP:%d HDMI:%d DVI:%d EDP:%d CRT:%d\n",
 		      port_name(port), is_dp, is_hdmi, is_dvi, is_edp, is_crt);
 
@@ -792,8 +796,15 @@
 	DRM_DEBUG_KMS("Set default to SSC at %dMHz\n", dev_priv->vbt.lvds_ssc_freq);
 
 	for (port = PORT_A; port < I915_MAX_PORTS; port++) {
+		struct ddi_vbt_port_info *info =
+			&dev_priv->vbt.ddi_port_info[port];
+
 		/* Recommended BSpec default: 800mV 0dB. */
-		dev_priv->vbt.ddi_port_info[port].hdmi_level_shift = 6;
+		info->hdmi_level_shift = 6;
+
+		info->supports_dvi = (port != PORT_A && port != PORT_E);
+		info->supports_hdmi = info->supports_dvi;
+		info->supports_dp = (port != PORT_E);
 	}
 }