diff --git a/drivers/gpu/drm/i915/intel_hdmi.c b/drivers/gpu/drm/i915/intel_hdmi.c index c33451aec1bd..2ff5d03b44ef 100644 --- a/drivers/gpu/drm/i915/intel_hdmi.c +++ b/drivers/gpu/drm/i915/intel_hdmi.c @@ -225,7 +225,52 @@ static const struct drm_encoder_funcs intel_hdmi_enc_funcs = { .destroy = intel_hdmi_enc_destroy, }; +/* + * Enumerate the child dev array parsed from VBT to check whether + * the given HDMI is present. + * If it is present, return 1. + * If it is not present, return false. + * If no child dev is parsed from VBT, it assumes that the given + * HDMI is present. + */ +int hdmi_is_present_in_vbt(struct drm_device *dev, int hdmi_reg) +{ + struct drm_i915_private *dev_priv = dev->dev_private; + struct child_device_config *p_child; + int i, hdmi_port, ret; + if (!dev_priv->child_dev_num) + return 1; + + if (hdmi_reg == SDVOB) + hdmi_port = DVO_B; + else if (hdmi_reg == SDVOC) + hdmi_port = DVO_C; + else if (hdmi_reg == HDMIB) + hdmi_port = DVO_B; + else if (hdmi_reg == HDMIC) + hdmi_port = DVO_C; + else if (hdmi_reg == HDMID) + hdmi_port = DVO_D; + else + return 0; + + ret = 0; + for (i = 0; i < dev_priv->child_dev_num; i++) { + p_child = dev_priv->child_dev + i; + /* + * If the device type is not HDMI, continue. + */ + if (p_child->device_type != DEVICE_TYPE_HDMI) + continue; + /* Find the HDMI port */ + if (p_child->dvo_port == hdmi_port) { + ret = 1; + break; + } + } + return ret; +} void intel_hdmi_init(struct drm_device *dev, int sdvox_reg) { struct drm_i915_private *dev_priv = dev->dev_private; @@ -233,6 +278,10 @@ void intel_hdmi_init(struct drm_device *dev, int sdvox_reg) struct intel_output *intel_output; struct intel_hdmi_priv *hdmi_priv; + if (!hdmi_is_present_in_vbt(dev, sdvox_reg)) { + DRM_DEBUG_KMS("HDMI is not present. Ignored it \n"); + return; + } intel_output = kcalloc(sizeof(struct intel_output) + sizeof(struct intel_hdmi_priv), 1, GFP_KERNEL); if (!intel_output)