[PATCH 09/12] drm/i915: Support DP MST in enc_to_dig_port() function

[Sean Paul]

From: Sean Paul <seanpaul at chromium.org>

Although DP_MST fake encoders are not subclassed from digital ports,
they are associated with them. Support these encoders.

Signed-off-by: Sean Paul <seanpaul at chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20191203173638.94919-9-sean@poorly.run #v1
Link: https://patchwork.freedesktop.org/patch/msgid/20191212190230.188505-10-sean@poorly.run #v2

Changes in v2:
-None
Changes in v3:
-None
---
 .../drm/i915/display/intel_display_types.h    | 25 +++++++++++--------
 1 file changed, 15 insertions(+), 10 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_display_types.h b/drivers/gpu/drm/i915/display/intel_display_types.h
index 340bdbf86260..7f31358297b3 100644
--- a/drivers/gpu/drm/i915/display/intel_display_types.h
+++ b/drivers/gpu/drm/i915/display/intel_display_types.h
@@ -1462,14 +1462,26 @@ static inline bool intel_encoder_is_dig_port(struct intel_encoder *encoder)
 	}
 }
 
+static inline bool intel_encoder_is_mst(struct intel_encoder *encoder)
+{
+	return encoder->type == INTEL_OUTPUT_DP_MST;
+}
+
+static inline struct intel_dp_mst_encoder *
+enc_to_mst(struct intel_encoder *encoder)
+{
+	return container_of(&encoder->base, struct intel_dp_mst_encoder,
+			    base.base);
+}
+
 static inline struct intel_digital_port *
 enc_to_dig_port(struct intel_encoder *encoder)
 {
-	struct intel_encoder *intel_encoder = encoder;
-
-	if (intel_encoder_is_dig_port(intel_encoder))
+	if (intel_encoder_is_dig_port(encoder))
 		return container_of(&encoder->base, struct intel_digital_port,
 				    base.base);
+	else if (intel_encoder_is_mst(encoder))
+		return enc_to_mst(encoder)->primary;
 	else
 		return NULL;
 }
@@ -1480,13 +1492,6 @@ conn_to_dig_port(struct intel_connector *connector)
 	return enc_to_dig_port(intel_attached_encoder(connector));
 }
 
-static inline struct intel_dp_mst_encoder *
-enc_to_mst(struct intel_encoder *encoder)
-{
-	return container_of(&encoder->base, struct intel_dp_mst_encoder,
-			    base.base);
-}
-
 static inline struct intel_dp *enc_to_intel_dp(struct intel_encoder *encoder)
 {
 	return &enc_to_dig_port(encoder)->dp;
-- 
Sean Paul, Software Engineer, Google / Chromium OS