phy: rcar: Add R-Car Gen3 PHY driver

Add a PHY driver for the R-Car Gen3 which allows configuring
USB OTG PHY on Gen3 into host mode and toggles VBUS in case a
dedicated regulator is present.

Signed-off-by: Marek Vasut <marek.vasut+renesas@gmail.com>
Cc: Nobuhiro Iwamatsu <iwamatsu@nigauri.org>
diff --git a/drivers/phy/phy-rcar-gen3.c b/drivers/phy/phy-rcar-gen3.c
new file mode 100644
index 0000000..b662935
--- /dev/null
+++ b/drivers/phy/phy-rcar-gen3.c
@@ -0,0 +1,161 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Renesas RCar Gen3 USB PHY driver
+ *
+ * Copyright (C) 2018 Marek Vasut <marek.vasut@gmail.com>
+ */
+
+#include <common.h>
+#include <clk.h>
+#include <div64.h>
+#include <dm.h>
+#include <fdtdec.h>
+#include <generic-phy.h>
+#include <reset.h>
+#include <syscon.h>
+#include <usb.h>
+#include <asm/io.h>
+#include <linux/bitops.h>
+#include <power/regulator.h>
+
+/* USB2.0 Host registers (original offset is +0x200) */
+#define USB2_INT_ENABLE		0x000
+#define USB2_USBCTR		0x00c
+#define USB2_SPD_RSM_TIMSET	0x10c
+#define USB2_OC_TIMSET		0x110
+#define USB2_COMMCTRL		0x600
+#define USB2_OBINTSTA		0x604
+#define USB2_OBINTEN		0x608
+#define USB2_VBCTRL		0x60c
+#define USB2_LINECTRL1		0x610
+#define USB2_ADPCTRL		0x630
+
+/* USBCTR */
+#define USB2_USBCTR_PLL_RST	BIT(1)
+
+/* SPD_RSM_TIMSET */
+#define USB2_SPD_RSM_TIMSET_INIT	0x014e029b
+
+/* OC_TIMSET */
+#define USB2_OC_TIMSET_INIT		0x000209ab
+
+/* COMMCTRL */
+#define USB2_COMMCTRL_OTG_PERI		BIT(31)	/* 1 = Peripheral mode */
+
+/* LINECTRL1 */
+#define USB2_LINECTRL1_DP_RPD		BIT(18)
+#define USB2_LINECTRL1_DM_RPD		BIT(16)
+
+/* ADPCTRL */
+#define USB2_ADPCTRL_DRVVBUS		BIT(4)
+
+struct rcar_gen3_phy {
+	fdt_addr_t	regs;
+	struct clk	clk;
+	struct udevice	*vbus_supply;
+};
+
+static int rcar_gen3_phy_phy_init(struct phy *phy)
+{
+	struct rcar_gen3_phy *priv = dev_get_priv(phy->dev);
+
+	/* Initialize USB2 part */
+	writel(0, priv->regs + USB2_INT_ENABLE);
+	writel(USB2_SPD_RSM_TIMSET_INIT, priv->regs + USB2_SPD_RSM_TIMSET);
+	writel(USB2_OC_TIMSET_INIT, priv->regs + USB2_OC_TIMSET);
+
+	setbits_le32(priv->regs + USB2_LINECTRL1,
+		     USB2_LINECTRL1_DP_RPD | USB2_LINECTRL1_DM_RPD);
+
+	clrbits_le32(priv->regs + USB2_COMMCTRL, USB2_COMMCTRL_OTG_PERI);
+
+	setbits_le32(priv->regs + USB2_ADPCTRL, USB2_ADPCTRL_DRVVBUS);
+
+	return 0;
+}
+
+static int rcar_gen3_phy_phy_power_on(struct phy *phy)
+{
+	struct rcar_gen3_phy *priv = dev_get_priv(phy->dev);
+	int ret;
+
+	if (priv->vbus_supply) {
+		ret = regulator_set_enable(priv->vbus_supply, true);
+		if (ret)
+			return ret;
+	}
+
+	setbits_le32(priv->regs + USB2_USBCTR, USB2_USBCTR_PLL_RST);
+	clrbits_le32(priv->regs + USB2_USBCTR, USB2_USBCTR_PLL_RST);
+
+	return 0;
+}
+
+static int rcar_gen3_phy_phy_power_off(struct phy *phy)
+{
+	struct rcar_gen3_phy *priv = dev_get_priv(phy->dev);
+
+	if (!priv->vbus_supply)
+		return 0;
+
+	return regulator_set_enable(priv->vbus_supply, false);
+}
+
+static const struct phy_ops rcar_gen3_phy_phy_ops = {
+	.init		= rcar_gen3_phy_phy_init,
+	.power_on	= rcar_gen3_phy_phy_power_on,
+	.power_off	= rcar_gen3_phy_phy_power_off,
+};
+
+static int rcar_gen3_phy_probe(struct udevice *dev)
+{
+	struct rcar_gen3_phy *priv = dev_get_priv(dev);
+	int ret;
+
+	priv->regs = dev_read_addr(dev);
+	if (priv->regs == FDT_ADDR_T_NONE)
+		return -EINVAL;
+
+	ret = device_get_supply_regulator(dev, "vbus-supply",
+					  &priv->vbus_supply);
+	if (ret && ret != -ENOENT) {
+		pr_err("Failed to get PHY regulator\n");
+		return ret;
+	}
+
+	/* Enable clock */
+	ret = clk_get_by_index(dev, 0, &priv->clk);
+	if (ret)
+		return ret;
+
+	ret = clk_enable(&priv->clk);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
+static int rcar_gen3_phy_remove(struct udevice *dev)
+{
+	struct rcar_gen3_phy *priv = dev_get_priv(dev);
+
+	clk_disable(&priv->clk);
+	clk_free(&priv->clk);
+
+	return 0;
+}
+
+static const struct udevice_id rcar_gen3_phy_of_match[] = {
+	{ .compatible = "renesas,rcar-gen3-usb2-phy", },
+	{ },
+};
+
+U_BOOT_DRIVER(rcar_gen3_phy) = {
+	.name		= "rcar-gen3-phy",
+	.id		= UCLASS_PHY,
+	.of_match	= rcar_gen3_phy_of_match,
+	.ops		= &rcar_gen3_phy_phy_ops,
+	.probe		= rcar_gen3_phy_probe,
+	.remove		= rcar_gen3_phy_remove,
+	.priv_auto_alloc_size = sizeof(struct rcar_gen3_phy),
+};