phy: add NXP PTN3222 eUSB2 to USB2 redriver

The NXP PTN3222 is the single-port eUSB2 to USB2 redriver that performs
translation between eUSB2 and USB2 signalling schemes. It supports all
three data rates: Low Speed, Full Speed and High Speed.

The reset state enables autonegotiation of the PHY role and of the data
rate, so no additional programming is required.

Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>
Tested-by: Konrad Dybcio <konradybcio@kernel.org>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Reviewed-by: Stephan Gerhold <stephan.gerhold@linaro.org>
Tested-by: Stephan Gerhold <stephan.gerhold@linaro.org>
Link: https://lore.kernel.org/r/20240830-nxp-ptn3222-v2-2-4c6d8535cf6c@linaro.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>

drivers/phy/Kconfig

@@ -82,6 +82,17 @@ config PHY_AIROHA_PCIE
 	  This driver create the basic PHY instance and provides initialize
 	  callback for PCIe GEN3 port.
 
+config PHY_NXP_PTN3222
+	tristate "NXP PTN3222 1-port eUSB2 to USB2 redriver"
+	depends on I2C
+	depends on OF
+	select GENERIC_PHY
+	help
+	  Enable this to support NXP PTN3222 1-port eUSB2 to USB2 Redriver.
+	  This redriver performs translation between eUSB2 and USB2 signalling
+	  schemes. It supports all three USB 2.0 data rates: Low Speed, Full
+	  Speed and High Speed.
+
 source "drivers/phy/allwinner/Kconfig"
 source "drivers/phy/amlogic/Kconfig"
 source "drivers/phy/broadcom/Kconfig"

drivers/phy/Makefile

@@ -11,6 +11,7 @@ obj-$(CONFIG_PHY_XGENE)			+= phy-xgene.o
 obj-$(CONFIG_PHY_PISTACHIO_USB)		+= phy-pistachio-usb.o
 obj-$(CONFIG_USB_LGM_PHY)		+= phy-lgm-usb.o
 obj-$(CONFIG_PHY_AIROHA_PCIE)		+= phy-airoha-pcie.o
+obj-$(CONFIG_PHY_NXP_PTN3222)		+= phy-nxp-ptn3222.o
 obj-y					+= allwinner/	\
 					   amlogic/	\
 					   broadcom/	\

drivers/phy/phy-nxp-ptn3222.c

@@ -0,0 +1,123 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2024, Linaro Limited
+ */
+
+#include <linux/gpio/consumer.h>
+#include <linux/i2c.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/phy/phy.h>
+#include <linux/regmap.h>
+#include <linux/regulator/consumer.h>
+
+#define NUM_SUPPLIES 2
+
+struct ptn3222 {
+	struct i2c_client *client;
+	struct phy *phy;
+	struct gpio_desc *reset_gpio;
+	struct regulator_bulk_data *supplies;
+};
+
+static int ptn3222_init(struct phy *phy)
+{
+	struct ptn3222 *ptn3222 = phy_get_drvdata(phy);
+	int ret;
+
+	ret = regulator_bulk_enable(NUM_SUPPLIES, ptn3222->supplies);
+	if (ret)
+		return ret;
+
+	gpiod_set_value_cansleep(ptn3222->reset_gpio, 0);
+
+	return 0;
+}
+
+static int ptn3222_exit(struct phy *phy)
+{
+	struct ptn3222 *ptn3222 = phy_get_drvdata(phy);
+
+	gpiod_set_value_cansleep(ptn3222->reset_gpio, 1);
+
+	return regulator_bulk_disable(NUM_SUPPLIES, ptn3222->supplies);
+}
+
+static const struct phy_ops ptn3222_ops = {
+	.init		= ptn3222_init,
+	.exit		= ptn3222_exit,
+	.owner		= THIS_MODULE,
+};
+
+static const struct regulator_bulk_data ptn3222_supplies[NUM_SUPPLIES] = {
+	{
+		.supply = "vdd3v3",
+		.init_load_uA = 11000,
+	}, {
+		.supply = "vdd1v8",
+		.init_load_uA = 55000,
+	}
+};
+
+static int ptn3222_probe(struct i2c_client *client)
+{
+	struct device *dev = &client->dev;
+	struct phy_provider *phy_provider;
+	struct ptn3222 *ptn3222;
+	int ret;
+
+	ptn3222 = devm_kzalloc(dev, sizeof(*ptn3222), GFP_KERNEL);
+	if (!ptn3222)
+		return -ENOMEM;
+
+	ptn3222->client = client;
+
+	ptn3222->reset_gpio = devm_gpiod_get_optional(dev, "reset",
+						      GPIOD_OUT_HIGH);
+	if (IS_ERR(ptn3222->reset_gpio))
+		return dev_err_probe(dev, PTR_ERR(ptn3222->reset_gpio),
+				     "unable to acquire reset gpio\n");
+
+	ret = devm_regulator_bulk_get_const(dev, NUM_SUPPLIES, ptn3222_supplies,
+					    &ptn3222->supplies);
+	if (ret)
+		return ret;
+
+	ptn3222->phy = devm_phy_create(dev, dev->of_node, &ptn3222_ops);
+	if (IS_ERR(ptn3222->phy)) {
+		dev_err(dev, "failed to create PHY: %d\n", ret);
+		return PTR_ERR(ptn3222->phy);
+	}
+
+	phy_set_drvdata(ptn3222->phy, ptn3222);
+
+	phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
+
+	return PTR_ERR_OR_ZERO(phy_provider);
+}
+
+static const struct i2c_device_id ptn3222_table[] = {
+	{ "ptn3222" },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, ptn3222_table);
+
+static const struct of_device_id ptn3222_of_table[] = {
+	{ .compatible = "nxp,ptn3222" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, ptn3222_of_table);
+
+static struct i2c_driver ptn3222_driver = {
+	.driver = {
+		.name = "ptn3222",
+		.of_match_table = ptn3222_of_table,
+	},
+	.probe = ptn3222_probe,
+	.id_table = ptn3222_table,
+};
+
+module_i2c_driver(ptn3222_driver);
+
+MODULE_DESCRIPTION("NXP PTN3222 eUSB2 Redriver driver");
+MODULE_LICENSE("GPL");