[PATCH v3 10/21] phy: renesas: rcar-gen3-usb2: Use mux-state for phyrst management

[Tommaso Merciai]

Add support for selecting the phyrst mux-state using the Linux mux
subsystem in the R-Car Gen3 USB2 PHY driver. This ensures correct hardware
initialization and integration with systems utilizing the mux-state device
tree property.

A temporary wrapper for optional muxes is introduced until native support
is available in the multiplexer subsystem.

Signed-off-by: Tommaso Merciai <tommaso.merciai.xr at bp.renesas.com>
---
v2->v3:
 - No changes

v1->v2:
 - New patch

 drivers/phy/renesas/phy-rcar-gen3-usb2.c | 34 ++++++++++++++++++++++++
 1 file changed, 34 insertions(+)

diff --git a/drivers/phy/renesas/phy-rcar-gen3-usb2.c b/drivers/phy/renesas/phy-rcar-gen3-usb2.c
index 6424fce18705..50817bffff34 100644
--- a/drivers/phy/renesas/phy-rcar-gen3-usb2.c
+++ b/drivers/phy/renesas/phy-rcar-gen3-usb2.c
@@ -17,6 +17,7 @@
 #include <linux/io.h>
 #include <linux/module.h>
 #include <linux/mutex.h>
+#include <linux/mux/consumer.h>
 #include <linux/of.h>
 #include <linux/phy/phy.h>
 #include <linux/platform_device.h>
@@ -948,11 +949,27 @@ static int rcar_gen3_phy_usb2_vbus_regulator_register(struct rcar_gen3_chan *cha
 	return rcar_gen3_phy_usb2_vbus_regulator_get_exclusive_enable(channel, enable);
 }
 
+/* Temporary wrapper until the multiplexer subsystem supports optional muxes */
+static inline struct mux_state *
+devm_mux_state_get_optional(struct device *dev, const char *mux_name)
+{
+	if (!of_property_present(dev->of_node, "mux-states"))
+		return NULL;
+
+	return devm_mux_state_get(dev, mux_name);
+}
+
+static void rcar_gen3_phy_mux_state_deselect(void *data)
+{
+	mux_state_deselect(data);
+}
+
 static int rcar_gen3_phy_usb2_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
 	struct rcar_gen3_chan *channel;
 	struct phy_provider *provider;
+	struct mux_state *mux_state;
 	int ret = 0, i, irq;
 
 	if (!dev->of_node) {
@@ -1019,6 +1036,23 @@ static int rcar_gen3_phy_usb2_probe(struct platform_device *pdev)
 		phy_set_drvdata(channel->rphys[i].phy, &channel->rphys[i]);
 	}
 
+	mux_state = devm_mux_state_get_optional(dev, NULL);
+	if (IS_ERR(mux_state)) {
+		if (PTR_ERR(mux_state) == -EPROBE_DEFER)
+			return PTR_ERR(mux_state);
+		mux_state = NULL;
+	} else {
+		ret = mux_state_select(mux_state);
+		if (ret)
+			return dev_err_probe(dev, ret, "Failed to select USB mux\n");
+
+		ret = devm_add_action_or_reset(dev, rcar_gen3_phy_mux_state_deselect,
+					       mux_state);
+		if (ret)
+			return dev_err_probe(dev, ret,
+					     "Failed to register USB mux state deselect\n");
+	}
+
 	if (channel->phy_data->no_adp_ctrl && channel->is_otg_channel) {
 		ret = rcar_gen3_phy_usb2_vbus_regulator_register(channel);
 		if (ret)
-- 
2.43.0