[Intel-gfx] [PATCH 7/9] drm/i915/bxt: Disable device ready before shutdown command

[Vidya Srinivas]

From: Uma Shankar <uma.shankar at intel.com>

Disable device ready before MIPI port shutdown command.
This helps to avoid mipi split screen issues.

Signed-off-by: Uma Shankar <uma.shankar at intel.com>
Signed-off-by: Vidya Srinivas <vidya.srinivas at intel.com>
---
 drivers/gpu/drm/i915/intel_dsi.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/drivers/gpu/drm/i915/intel_dsi.c b/drivers/gpu/drm/i915/intel_dsi.c
index 808158f..12aeee1 100644
--- a/drivers/gpu/drm/i915/intel_dsi.c
+++ b/drivers/gpu/drm/i915/intel_dsi.c
@@ -603,6 +603,8 @@ static void intel_dsi_pre_disable(struct intel_encoder *encoder,
 				  struct intel_crtc_state *old_crtc_state,
 				  struct drm_connector_state *old_conn_state)
 {
+	struct drm_device *dev = encoder->base.dev;
+	struct drm_i915_private *dev_priv = dev->dev_private;
 	struct intel_dsi *intel_dsi = enc_to_intel_dsi(&encoder->base);
 	enum port port;
 
@@ -610,6 +612,15 @@ static void intel_dsi_pre_disable(struct intel_encoder *encoder,
 
 	intel_panel_disable_backlight(intel_dsi->attached_connector);
 
+	/*
+	 * Disable Device ready before the port shutdown in order
+	 * to avoid split screen
+	 */
+	if (IS_BROXTON(dev_priv)) {
+		for_each_dsi_port(port, intel_dsi->ports)
+			I915_WRITE(MIPI_DEVICE_READY(port), 0);
+	}
+
 	if (is_vid_mode(intel_dsi)) {
 		/* Send Shutdown command to the panel in LP mode */
 		for_each_dsi_port(port, intel_dsi->ports)
-- 
1.9.1