diff --git a/drivers/gpu/drm/i915/intel_ddi.c b/drivers/gpu/drm/i915/intel_ddi.c index 612400fab559..a69db463557f 100644 --- a/drivers/gpu/drm/i915/intel_ddi.c +++ b/drivers/gpu/drm/i915/intel_ddi.c @@ -3282,6 +3282,33 @@ void intel_ddi_init(struct drm_device *dev, enum port port) struct intel_encoder *intel_encoder; struct drm_encoder *encoder; bool init_hdmi, init_dp; + int max_lanes; + + if (I915_READ(DDI_BUF_CTL(PORT_A)) & DDI_A_4_LANES) { + switch (port) { + case PORT_A: + max_lanes = 4; + break; + case PORT_E: + max_lanes = 0; + break; + default: + max_lanes = 4; + break; + } + } else { + switch (port) { + case PORT_A: + max_lanes = 2; + break; + case PORT_E: + max_lanes = 2; + break; + default: + max_lanes = 4; + break; + } + } init_hdmi = (dev_priv->vbt.ddi_port_info[port].supports_dvi || dev_priv->vbt.ddi_port_info[port].supports_hdmi); @@ -3292,6 +3319,15 @@ void intel_ddi_init(struct drm_device *dev, enum port port) return; } + if (WARN(max_lanes == 0, + "No lanes for port %c\n", port_name(port))) + return; + + if (WARN(init_hdmi && max_lanes < 4, + "Not enough lanes (%d) for HDMI on port %c\n", + max_lanes, port_name(port))) + init_hdmi = false; + intel_dig_port = kzalloc(sizeof(*intel_dig_port), GFP_KERNEL); if (!intel_dig_port) return;