phy: socionext: add USB2 PHY driver for UniPhier SoC

Add a driver for PHY interface built into USB2 controller implemented on
UniPhier SoCs. This driver supports HS-PHY for Pro4 and LD11.

Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
diff --git a/drivers/phy/socionext/Kconfig b/drivers/phy/socionext/Kconfig
index 4a172fc..497ca38 100644
--- a/drivers/phy/socionext/Kconfig
+++ b/drivers/phy/socionext/Kconfig
@@ -2,6 +2,19 @@
 # PHY drivers for Socionext platforms.
 #
 
+config PHY_UNIPHIER_USB2
+	tristate "UniPhier USB2 PHY driver"
+	depends on ARCH_UNIPHIER || COMPILE_TEST
+	depends on OF && HAS_IOMEM
+	select GENERIC_PHY
+	select MFD_SYSCON
+	help
+	  Enable this to support USB PHY implemented on USB2 controller
+	  on UniPhier SoCs. This driver provides interface to interact
+	  with USB 2.0 PHY that is part of the UniPhier SoC.
+	  In case of Pro4, it is necessary to specify this USB2 PHY instead
+	  of USB3 HS-PHY.
+
 config PHY_UNIPHIER_USB3
 	tristate "UniPhier USB3 PHY driver"
 	depends on ARCH_UNIPHIER || COMPILE_TEST
diff --git a/drivers/phy/socionext/Makefile b/drivers/phy/socionext/Makefile
index e230fa31..91e4825 100644
--- a/drivers/phy/socionext/Makefile
+++ b/drivers/phy/socionext/Makefile
@@ -3,4 +3,5 @@
 # Makefile for the phy drivers.
 #
 
+obj-$(CONFIG_PHY_UNIPHIER_USB2)	+= phy-uniphier-usb2.o
 obj-$(CONFIG_PHY_UNIPHIER_USB3)	+= phy-uniphier-usb3hs.o phy-uniphier-usb3ss.o
diff --git a/drivers/phy/socionext/phy-uniphier-usb2.c b/drivers/phy/socionext/phy-uniphier-usb2.c
new file mode 100644
index 0000000..3f2086e
--- /dev/null
+++ b/drivers/phy/socionext/phy-uniphier-usb2.c
@@ -0,0 +1,244 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * phy-uniphier-usb2.c - PHY driver for UniPhier USB2 controller
+ * Copyright 2015-2018 Socionext Inc.
+ * Author:
+ *      Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
+ */
+
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/phy/phy.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/regulator/consumer.h>
+
+#define SG_USBPHY1CTRL		0x500
+#define SG_USBPHY1CTRL2		0x504
+#define SG_USBPHY2CTRL		0x508
+#define SG_USBPHY2CTRL2		0x50c	/* LD11 */
+#define SG_USBPHY12PLL		0x50c	/* Pro4 */
+#define SG_USBPHY3CTRL		0x510
+#define SG_USBPHY3CTRL2		0x514
+#define SG_USBPHY4CTRL		0x518	/* Pro4 */
+#define SG_USBPHY4CTRL2		0x51c	/* Pro4 */
+#define SG_USBPHY34PLL		0x51c	/* Pro4 */
+
+struct uniphier_u2phy_param {
+	u32 offset;
+	u32 value;
+};
+
+struct uniphier_u2phy_soc_data {
+	struct uniphier_u2phy_param config0;
+	struct uniphier_u2phy_param config1;
+};
+
+struct uniphier_u2phy_priv {
+	struct regmap *regmap;
+	struct phy *phy;
+	struct regulator *vbus;
+	const struct uniphier_u2phy_soc_data *data;
+	struct uniphier_u2phy_priv *next;
+};
+
+static int uniphier_u2phy_power_on(struct phy *phy)
+{
+	struct uniphier_u2phy_priv *priv = phy_get_drvdata(phy);
+	int ret = 0;
+
+	if (priv->vbus)
+		ret = regulator_enable(priv->vbus);
+
+	return ret;
+}
+
+static int uniphier_u2phy_power_off(struct phy *phy)
+{
+	struct uniphier_u2phy_priv *priv = phy_get_drvdata(phy);
+
+	if (priv->vbus)
+		regulator_disable(priv->vbus);
+
+	return 0;
+}
+
+static int uniphier_u2phy_init(struct phy *phy)
+{
+	struct uniphier_u2phy_priv *priv = phy_get_drvdata(phy);
+
+	if (!priv->data)
+		return 0;
+
+	regmap_write(priv->regmap, priv->data->config0.offset,
+		     priv->data->config0.value);
+	regmap_write(priv->regmap, priv->data->config1.offset,
+		     priv->data->config1.value);
+
+	return 0;
+}
+
+static struct phy *uniphier_u2phy_xlate(struct device *dev,
+					struct of_phandle_args *args)
+{
+	struct uniphier_u2phy_priv *priv = dev_get_drvdata(dev);
+
+	while (priv && args->np != priv->phy->dev.of_node)
+		priv = priv->next;
+
+	if (!priv) {
+		dev_err(dev, "Failed to find appropriate phy\n");
+		return ERR_PTR(-EINVAL);
+	}
+
+	return priv->phy;
+}
+
+static const struct phy_ops uniphier_u2phy_ops = {
+	.init      = uniphier_u2phy_init,
+	.power_on  = uniphier_u2phy_power_on,
+	.power_off = uniphier_u2phy_power_off,
+	.owner = THIS_MODULE,
+};
+
+static int uniphier_u2phy_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct device_node *parent, *child;
+	struct uniphier_u2phy_priv *priv = NULL, *next = NULL;
+	struct phy_provider *phy_provider;
+	struct regmap *regmap;
+	const struct uniphier_u2phy_soc_data *data;
+	int ret, data_idx, ndatas;
+
+	data = of_device_get_match_data(dev);
+	if (WARN_ON(!data))
+		return -EINVAL;
+
+	/* get number of data */
+	for (ndatas = 0; data[ndatas].config0.offset; ndatas++)
+		;
+
+	parent = of_get_parent(dev->of_node);
+	regmap = syscon_node_to_regmap(parent);
+	of_node_put(parent);
+	if (IS_ERR(regmap)) {
+		dev_err(dev, "Failed to get regmap\n");
+		return PTR_ERR(regmap);
+	}
+
+	for_each_child_of_node(dev->of_node, child) {
+		priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+		if (!priv) {
+			ret = -ENOMEM;
+			goto out_put_child;
+		}
+		priv->regmap = regmap;
+
+		priv->vbus = devm_regulator_get_optional(dev, "vbus");
+		if (IS_ERR(priv->vbus)) {
+			if (PTR_ERR(priv->vbus) == -EPROBE_DEFER) {
+				ret = PTR_ERR(priv->vbus);
+				goto out_put_child;
+			}
+			priv->vbus = NULL;
+		}
+
+		priv->phy = devm_phy_create(dev, child, &uniphier_u2phy_ops);
+		if (IS_ERR(priv->phy)) {
+			dev_err(dev, "Failed to create phy\n");
+			ret = PTR_ERR(priv->phy);
+			goto out_put_child;
+		}
+
+		ret = of_property_read_u32(child, "reg", &data_idx);
+		if (ret) {
+			dev_err(dev, "Failed to get reg property\n");
+			goto out_put_child;
+		}
+
+		if (data_idx < ndatas)
+			priv->data = &data[data_idx];
+		else
+			dev_warn(dev, "No phy configuration: %s\n",
+				 child->full_name);
+
+		phy_set_drvdata(priv->phy, priv);
+		priv->next = next;
+		next = priv;
+	}
+
+	dev_set_drvdata(dev, priv);
+	phy_provider = devm_of_phy_provider_register(dev,
+						     uniphier_u2phy_xlate);
+	return PTR_ERR_OR_ZERO(phy_provider);
+
+out_put_child:
+	of_node_put(child);
+
+	return ret;
+}
+
+static const struct uniphier_u2phy_soc_data uniphier_pro4_data[] = {
+	{
+		.config0 = { SG_USBPHY1CTRL, 0x05142400 },
+		.config1 = { SG_USBPHY12PLL, 0x00010010 },
+	},
+	{
+		.config0 = { SG_USBPHY2CTRL, 0x05142400 },
+		.config1 = { SG_USBPHY12PLL, 0x00010010 },
+	},
+	{
+		.config0 = { SG_USBPHY3CTRL, 0x05142400 },
+		.config1 = { SG_USBPHY34PLL, 0x00010010 },
+	},
+	{
+		.config0 = { SG_USBPHY4CTRL, 0x05142400 },
+		.config1 = { SG_USBPHY34PLL, 0x00010010 },
+	},
+	{ /* sentinel */ }
+};
+
+static const struct uniphier_u2phy_soc_data uniphier_ld11_data[] = {
+	{
+		.config0 = { SG_USBPHY1CTRL,  0x82280000 },
+		.config1 = { SG_USBPHY1CTRL2, 0x00000106 },
+	},
+	{
+		.config0 = { SG_USBPHY2CTRL,  0x82280000 },
+		.config1 = { SG_USBPHY2CTRL2, 0x00000106 },
+	},
+	{
+		.config0 = { SG_USBPHY3CTRL,  0x82280000 },
+		.config1 = { SG_USBPHY3CTRL2, 0x00000106 },
+	},
+	{ /* sentinel */ }
+};
+
+static const struct of_device_id uniphier_u2phy_match[] = {
+	{
+		.compatible = "socionext,uniphier-pro4-usb2-phy",
+		.data = &uniphier_pro4_data,
+	},
+	{
+		.compatible = "socionext,uniphier-ld11-usb2-phy",
+		.data = &uniphier_ld11_data,
+	},
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, uniphier_u2phy_match);
+
+static struct platform_driver uniphier_u2phy_driver = {
+	.probe = uniphier_u2phy_probe,
+	.driver = {
+		.name = "uniphier-usb2-phy",
+		.of_match_table = uniphier_u2phy_match,
+	},
+};
+module_platform_driver(uniphier_u2phy_driver);
+
+MODULE_AUTHOR("Kunihiko Hayashi <hayashi.kunihiko@socionext.com>");
+MODULE_DESCRIPTION("UniPhier PHY driver for USB2 controller");
+MODULE_LICENSE("GPL v2");