[Intel-gfx] [PATCH 03/11] drm/i915: Disable HDCP signalling on transcoder disable

[Sean Paul]

From: Sean Paul <seanpaul at chromium.org>

Currently we rely on intel_hdcp_disable() to disable HDCP signalling in
the DDI Function Control register. This patch adds a safety net by also
clearing the bit when we disable the transcoder.

Once we have HDCP over MST and disappearing connectors, we want to make
sure that the signalling is truly disabled even if HDCP teardown doesn't
go as planned.

Signed-off-by: Sean Paul <seanpaul at chromium.org>
---
 drivers/gpu/drm/i915/display/intel_ddi.c | 13 ++++++-------
 1 file changed, 6 insertions(+), 7 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_ddi.c b/drivers/gpu/drm/i915/display/intel_ddi.c
index b51f244ad7a5..e8ac98a8ee7f 100644
--- a/drivers/gpu/drm/i915/display/intel_ddi.c
+++ b/drivers/gpu/drm/i915/display/intel_ddi.c
@@ -1952,13 +1952,12 @@ void intel_ddi_disable_transcoder_func(const struct intel_crtc_state *crtc_state
 	i915_reg_t reg = TRANS_DDI_FUNC_CTL(cpu_transcoder);
 	u32 val = I915_READ(reg);
 
-	if (INTEL_GEN(dev_priv) >= 12) {
-		val &= ~(TRANS_DDI_FUNC_ENABLE | TGL_TRANS_DDI_PORT_MASK |
-			 TRANS_DDI_DP_VC_PAYLOAD_ALLOC);
-	} else {
-		val &= ~(TRANS_DDI_FUNC_ENABLE | TRANS_DDI_PORT_MASK |
-			 TRANS_DDI_DP_VC_PAYLOAD_ALLOC);
-	}
+	val &= ~(TRANS_DDI_FUNC_ENABLE | TRANS_DDI_DP_VC_PAYLOAD_ALLOC |
+		 TRANS_DDI_HDCP_SIGNALLING);
+	if (INTEL_GEN(dev_priv) >= 12)
+		val &= ~TGL_TRANS_DDI_PORT_MASK;
+	else
+		val &= ~TRANS_DDI_PORT_MASK;
 	I915_WRITE(reg, val);
 
 	if (dev_priv->quirks & QUIRK_INCREASE_DDI_DISABLED_TIME &&
-- 
Sean Paul, Software Engineer, Google / Chromium OS