[PATCH v2 04/11] drm/bridge: dp_typec: Support USB Type-C orientation

[Stephen Boyd <swboyd@chromium.org>]

Add an orientation parameter to drm_dp_typec_bridge_assign_pins() so
that the DP lanes can be directed to the proper USB type-c pins on the
connector when the cable is flipped. This is mostly useful for the case
where the DP lanes are directly connected to the usb-c-connector and the
device doesn't have an orientation switch wired down on the board
between the connector and the DP controller. Flip the lanes to match the
physical pin locations on the connector when the orientation is reverse.

Cc: Prashant Malani <pmalani@chromium.org>
Cc: Benson Leung <bleung@chromium.org>
Cc: Tzung-Bi Shih <tzungbi@kernel.org>
Cc: <chrome-platform@lists.linux.dev>
Cc: Pin-yen Lin <treapking@chromium.org>
Cc: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
---
 drivers/gpu/drm/bridge/aux-hpd-bridge.c | 44 ++++++++++++++++++-------
 include/drm/bridge/aux-bridge.h         |  7 ++--
 2 files changed, 37 insertions(+), 14 deletions(-)

diff --git a/drivers/gpu/drm/bridge/aux-hpd-bridge.c b/drivers/gpu/drm/bridge/aux-hpd-bridge.c
index 716b2220bdd5..79652d27db40 100644
--- a/drivers/gpu/drm/bridge/aux-hpd-bridge.c
+++ b/drivers/gpu/drm/bridge/aux-hpd-bridge.c
@@ -7,6 +7,7 @@
 #include <linux/auxiliary_bus.h>
 #include <linux/module.h>
 #include <linux/of.h>
+#include <linux/usb/typec.h>
 #include <linux/usb/typec_dp.h>
 
 #include <drm/drm_atomic_state_helper.h>
@@ -321,17 +322,35 @@ static int dp_lane_to_typec_lane(enum dp_lane lane)
 	return -EINVAL;
 }
 
-static int typec_to_dp_lane(enum usb_ss_lane lane)
+static int typec_to_dp_lane(enum usb_ss_lane lane,
+			    enum typec_orientation orientation)
 {
-	switch (lane) {
-	case USB_SSRX1:
-		return DP_ML3;
-	case USB_SSTX1:
-		return DP_ML2;
-	case USB_SSTX2:
-		return DP_ML0;
-	case USB_SSRX2:
-		return DP_ML1;
+	switch (orientation) {
+	case TYPEC_ORIENTATION_NONE:
+	case TYPEC_ORIENTATION_NORMAL:
+		switch (lane) {
+		case USB_SSRX1:
+			return DP_ML3;
+		case USB_SSTX1:
+			return DP_ML2;
+		case USB_SSTX2:
+			return DP_ML0;
+		case USB_SSRX2:
+			return DP_ML1;
+		}
+		break;
+	case TYPEC_ORIENTATION_REVERSE:
+		switch (lane) {
+		case USB_SSRX1:
+			return DP_ML0;
+		case USB_SSTX1:
+			return DP_ML1;
+		case USB_SSTX2:
+			return DP_ML3;
+		case USB_SSRX2:
+			return DP_ML2;
+		}
+		break;
 	}
 
 	return -EINVAL;
@@ -341,6 +360,7 @@ static int typec_to_dp_lane(enum usb_ss_lane lane)
  * drm_dp_typec_bridge_assign_pins - Assign DisplayPort (DP) lanes to USB type-C pins
  * @typec_bridge_dev: Device created for the type-c bridge
  * @conf: DisplayPort altmode configure command VDO content
+ * @orientation: Orientation of USB type-c port
  * @lane_mapping: Physical (array index) to logical (array value) USB type-C lane mapping
  *
  * Assign DP lanes to the USB type-C pins for the DP altmode configuration
@@ -351,7 +371,7 @@ static int typec_to_dp_lane(enum usb_ss_lane lane)
  * Return: 0 on success, negative value for failure.
  */
 int drm_dp_typec_bridge_assign_pins(struct drm_dp_typec_bridge_dev *typec_bridge_dev,
-				     u32 conf,
+				     u32 conf, enum typec_orientation orientation,
 				     enum usb_ss_lane lane_mapping[NUM_USB_SS])
 {
 	struct auxiliary_device *adev = &typec_bridge_dev->adev;
@@ -388,7 +408,7 @@ int drm_dp_typec_bridge_assign_pins(struct drm_dp_typec_bridge_dev *typec_bridge
 		typec_lane = lane_mapping[typec_lane];
 
 		/* Map logical type-c lane to logical DP lane */
-		dp_lanes[i] = typec_to_dp_lane(typec_lane);
+		dp_lanes[i] = typec_to_dp_lane(typec_lane, orientation);
 	}
 
 	return 0;
diff --git a/include/drm/bridge/aux-bridge.h b/include/drm/bridge/aux-bridge.h
index aaace808772c..258b87c93623 100644
--- a/include/drm/bridge/aux-bridge.h
+++ b/include/drm/bridge/aux-bridge.h
@@ -7,6 +7,8 @@
 #ifndef DRM_AUX_BRIDGE_H
 #define DRM_AUX_BRIDGE_H
 
+#include <linux/usb/typec.h>
+
 #include <drm/drm_connector.h>
 
 struct auxiliary_device;
@@ -53,7 +55,8 @@ int devm_drm_dp_typec_bridge_add(struct device *dev, struct drm_dp_typec_bridge_
 void drm_dp_typec_bridge_notify(struct drm_dp_typec_bridge_dev *typec_bridge_dev,
 				enum drm_connector_status status);
 int drm_dp_typec_bridge_assign_pins(struct drm_dp_typec_bridge_dev *typec_bridge_dev, u32 conf,
-				     enum usb_ss_lane lane_mapping[NUM_USB_SS]);
+				    enum typec_orientation orientation,
+				    enum usb_ss_lane lane_mapping[NUM_USB_SS]);
 #else
 static inline struct auxiliary_device *devm_drm_dp_hpd_bridge_alloc(struct device *parent,
 								    struct device_node *np)
@@ -94,7 +97,7 @@ static inline void drm_dp_typec_bridge_notify(struct drm_dp_typec_bridge_dev *ty
 }
 
 static inline int drm_dp_typec_bridge_assign_pins(struct drm_dp_typec_bridge_dev *typec_bridge_dev,
-						  u32 conf,
+						  u32 conf, enum typec_orientation orientation,
 						  enum usb_ss_lane lane_mapping[NUM_USB_SS])
 {
 	return 0;
-- 
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