[PATCH 04/12] drm/i915: touch the DIP control register after enabling the HDMI port

[Paulo Zanoni <przanoni@gmail.com>]

From: Paulo Zanoni <paulo.r.zanoni@intel.com>

Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
---
 drivers/gpu/drm/i915/intel_hdmi.c |   22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/drivers/gpu/drm/i915/intel_hdmi.c b/drivers/gpu/drm/i915/intel_hdmi.c
index 1eef50d..8646a50 100644
--- a/drivers/gpu/drm/i915/intel_hdmi.c
+++ b/drivers/gpu/drm/i915/intel_hdmi.c
@@ -113,6 +113,20 @@ static u32 intel_infoframe_flags(struct dip_infoframe *frame)
 	return flags;
 }
 
+static u32 intel_get_dip_ctl_reg(struct drm_encoder *encoder)
+{
+	struct drm_device *dev = encoder->dev;
+	struct intel_crtc *intel_crtc = to_intel_crtc(encoder->crtc);
+
+	if (!HAS_PCH_SPLIT(dev)) {
+		return VIDEO_DIP_CTL;
+	} else if (IS_VALLEYVIEW(dev)) {
+		return VLV_TVIDEO_DIP_CTL(intel_crtc->pipe);
+	} else {
+		return TVIDEO_DIP_CTL(intel_crtc->pipe);
+	}
+}
+
 static void i9xx_write_infoframe(struct drm_encoder *encoder,
 				 struct dip_infoframe *frame)
 {
@@ -331,6 +345,14 @@ static void intel_hdmi_dpms(struct drm_encoder *encoder, int mode)
 		I915_WRITE(intel_hdmi->sdvox_reg, temp);
 		POSTING_READ(intel_hdmi->sdvox_reg);
 	}
+
+	if ((mode == DRM_MODE_DPMS_ON) && encoder->crtc) {
+		/* We've just enabled the HDMI port. Now we need to touch the
+		 * DIP control register to make sure the infoframes are sent.
+		 */
+		u32 dip_reg = intel_get_dip_ctl_reg(encoder);
+		I915_WRITE(dip_reg, I915_READ(dip_reg));
+	}
 }
 
 static int intel_hdmi_mode_valid(struct drm_connector *connector,
-- 
1.7.10