[PATCH 2/5] drm/i915/tc: Add separate intel_tc_phy_port_to_tc() for TC DDI/PHY ports

[Imre Deak <imre.deak@intel.com>]

intel_port_to_tc() returns the PORT_TC1..6 -> TC_PORT_1..6 mapping only
for DDI ports that are connected to a TypeC PHY. In some cases this
mapping is also required for TypeC DDI ports which are not connected to
a TypeC PHY. Such DDI ports are the PORT_TC1..4 ports on RKL/ADLS/BMG.

Add a separate intel_tc_phy_to_tc() helper to return the mapping for
ports connected to a TypeC PHY, and make all the current users - which
expect this semantic - call this helper. A follow-up change will need to
get the same mapping for TypeC DDI ports not connected to a TypeC PHY,
leave intel_port_to_tc() exported for that.

Cc: Suraj Kandpal <suraj.kandpal@intel.com>
Cc: Mika Kahola <mika.kahola@intel.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
---
 drivers/gpu/drm/i915/display/intel_ddi.c     |  4 ++--
 drivers/gpu/drm/i915/display/intel_display.c | 23 ++++++++++++++++----
 drivers/gpu/drm/i915/display/intel_display.h |  1 +
 3 files changed, 22 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_ddi.c b/drivers/gpu/drm/i915/display/intel_ddi.c
index 8471bdab5c62f..ed9798b0ec009 100644
--- a/drivers/gpu/drm/i915/display/intel_ddi.c
+++ b/drivers/gpu/drm/i915/display/intel_ddi.c
@@ -5148,7 +5148,7 @@ static const char *intel_ddi_encoder_name(struct intel_display *display,
 			       port_name(port - PORT_D_XELPD + PORT_D),
 			       phy_name(phy));
 	} else if (DISPLAY_VER(display) >= 12) {
-		enum tc_port tc_port = intel_port_to_tc(display, port);
+		enum tc_port tc_port = intel_tc_phy_port_to_tc(display, port);
 
 		seq_buf_printf(s, "DDI %s%c/PHY %s%c",
 			       port >= PORT_TC1 ? "TC" : "",
@@ -5156,7 +5156,7 @@ static const char *intel_ddi_encoder_name(struct intel_display *display,
 			       tc_port != TC_PORT_NONE ? "TC" : "",
 			       tc_port != TC_PORT_NONE ? tc_port_name(tc_port) : phy_name(phy));
 	} else if (DISPLAY_VER(display) >= 11) {
-		enum tc_port tc_port = intel_port_to_tc(display, port);
+		enum tc_port tc_port = intel_tc_phy_port_to_tc(display, port);
 
 		seq_buf_printf(s, "DDI %c%s/PHY %s%c",
 			       port_name(port),
diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
index 6c8a7f63111ec..a8a3e80001870 100644
--- a/drivers/gpu/drm/i915/display/intel_display.c
+++ b/drivers/gpu/drm/i915/display/intel_display.c
@@ -1859,17 +1859,32 @@ enum phy intel_port_to_phy(struct intel_display *display, enum port port)
 }
 
 /* Prefer intel_encoder_to_tc() */
+/*
+ * Return TC_PORT_1..I915_MAX_TC_PORTS for any TypeC DDI port. The function
+ * can be also called for TypeC DDI ports not connected to a TypeC PHY such as
+ * the PORT_TC1..4 ports on RKL/ADLS/BMG.
+ */
 enum tc_port intel_port_to_tc(struct intel_display *display, enum port port)
 {
-	if (!intel_phy_is_tc(display, intel_port_to_phy(display, port)))
-		return TC_PORT_NONE;
-
 	if (DISPLAY_VER(display) >= 12)
 		return TC_PORT_1 + port - PORT_TC1;
 	else
 		return TC_PORT_1 + port - PORT_C;
 }
 
+/*
+ * Return TC_PORT_1..I915_MAX_TC_PORTS for TypeC DDI ports connected to a TypeC PHY.
+ * Note that on RKL, ADLS, BMG the PORT_TC1..4 ports are connected to a non-TypeC
+ * PHY, so on those platforms the function returns TC_PORT_NONE.
+ */
+enum tc_port intel_tc_phy_port_to_tc(struct intel_display *display, enum port port)
+{
+	if (!intel_phy_is_tc(display, intel_port_to_phy(display, port)))
+		return TC_PORT_NONE;
+
+	return intel_port_to_tc(display, port);
+}
+
 enum phy intel_encoder_to_phy(struct intel_encoder *encoder)
 {
 	struct intel_display *display = to_intel_display(encoder);
@@ -1902,7 +1917,7 @@ enum tc_port intel_encoder_to_tc(struct intel_encoder *encoder)
 {
 	struct intel_display *display = to_intel_display(encoder);
 
-	return intel_port_to_tc(display, encoder->port);
+	return intel_tc_phy_port_to_tc(display, encoder->port);
 }
 
 enum intel_display_power_domain
diff --git a/drivers/gpu/drm/i915/display/intel_display.h b/drivers/gpu/drm/i915/display/intel_display.h
index bcc6ccb69d2b5..f8e6e4e827222 100644
--- a/drivers/gpu/drm/i915/display/intel_display.h
+++ b/drivers/gpu/drm/i915/display/intel_display.h
@@ -451,6 +451,7 @@ bool intel_phy_is_combo(struct intel_display *display, enum phy phy);
 bool intel_phy_is_tc(struct intel_display *display, enum phy phy);
 bool intel_phy_is_snps(struct intel_display *display, enum phy phy);
 enum tc_port intel_port_to_tc(struct intel_display *display, enum port port);
+enum tc_port intel_tc_phy_port_to_tc(struct intel_display *display, enum port port);
 
 enum phy intel_encoder_to_phy(struct intel_encoder *encoder);
 bool intel_encoder_is_combo(struct intel_encoder *encoder);
-- 
2.49.1