usb: typec-mux: ptn36502: broadcast typec state to next mux

In the Type-C graph, the ptn36502 retimer is in between the USB-C
connector and the USB3/DP combo PHY, and this PHY also requires the
USB-C mode events to properly set-up the SuperSpeed Lanes functions
to setup USB3-only, USB3 + DP Altmode or DP Altmode only on the 4 lanes.

Update the ptn36502 retimer to get an optional type-c mux on the next
endpoint, and broadcast the received mode to it.
Tested-by: Luca Weiss <luca.weiss@fairphone.com>
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://lore.kernel.org/r/20240606-topic-sm8x50-upstream-retimer-broadcast-mode-v2-3-c6f6eae479c3@linaro.orgSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/typec/mux/ptn36502.c

@@ -67,6 +67,7 @@ struct ptn36502 {
 	struct typec_retimer *retimer;
 
 	struct typec_switch *typec_switch;
+	struct typec_mux *typec_mux;
 
 	struct mutex lock; /* protect non-concurrent retimer & switch */
 
@@ -235,6 +236,7 @@ static int ptn36502_sw_set(struct typec_switch_dev *sw, enum typec_orientation o
 static int ptn36502_retimer_set(struct typec_retimer *retimer, struct typec_retimer_state *state)
 {
 	struct ptn36502 *ptn = typec_retimer_get_drvdata(retimer);
+	struct typec_mux_state mux_state;
 	int ret = 0;
 
 	mutex_lock(&ptn->lock);
@@ -252,7 +254,14 @@ static int ptn36502_retimer_set(struct typec_retimer *retimer, struct typec_reti
 
 	mutex_unlock(&ptn->lock);
 
-	return ret;
+	if (ret)
+		return ret;
+
+	mux_state.alt = state->alt;
+	mux_state.data = state->data;
+	mux_state.mode = state->mode;
+
+	return typec_mux_set(ptn->typec_mux, &mux_state);
 }
 
 static int ptn36502_detect(struct ptn36502 *ptn)
@@ -321,10 +330,17 @@ static int ptn36502_probe(struct i2c_client *client)
 		return dev_err_probe(dev, PTR_ERR(ptn->typec_switch),
 				     "Failed to acquire orientation-switch\n");
 
+	ptn->typec_mux = fwnode_typec_mux_get(dev->fwnode);
+	if (IS_ERR(ptn->typec_mux)) {
+		ret = dev_err_probe(dev, PTR_ERR(ptn->typec_mux),
+				    "Failed to acquire mode-switch\n");
+		goto err_switch_put;
+	}
+
 	ret = regulator_enable(ptn->vdd18_supply);
 	if (ret) {
 		ret = dev_err_probe(dev, ret, "Failed to enable vdd18\n");
-		goto err_switch_put;
+		goto err_mux_put;
 	}
 
 	ret = ptn36502_detect(ptn);
@@ -365,6 +381,9 @@ static int ptn36502_probe(struct i2c_client *client)
 err_disable_regulator:
 	regulator_disable(ptn->vdd18_supply);
 
+err_mux_put:
+	typec_mux_put(ptn->typec_mux);
+
 err_switch_put:
 	typec_switch_put(ptn->typec_switch);
 
@@ -380,6 +399,7 @@ static void ptn36502_remove(struct i2c_client *client)
 
 	regulator_disable(ptn->vdd18_supply);
 
+	typec_mux_put(ptn->typec_mux);
 	typec_switch_put(ptn->typec_switch);
 }