[PATCH 5/7] phy: spacemit: add USB3 support for K1 PCIe/USB3 combo PHY

[Ze Huang]

Add support for USB 3.0 mode on the K1 PCIe/USB3 combo PHY. Currently,
only USB mode is supported; PCIe support is not included in this change.

Signed-off-by: Ze Huang <huangze@xxxxxxxxxxx>
---
 drivers/phy/spacemit/Kconfig          |   8 ++
 drivers/phy/spacemit/Makefile         |   1 +
 drivers/phy/spacemit/phy-k1-combphy.c | 229 ++++++++++++++++++++++++++++++++++
 3 files changed, 238 insertions(+)

diff --git a/drivers/phy/spacemit/Kconfig b/drivers/phy/spacemit/Kconfig
index f0c2a33f53cc810e71c6140ae957aa68a2b6ff0c..12749aba756329cf64fb9199055ba484fe05f3ab 100644
--- a/drivers/phy/spacemit/Kconfig
+++ b/drivers/phy/spacemit/Kconfig
@@ -10,3 +10,11 @@ config PHY_SPACEMIT_K1_USB2
 	help
 	  Enable this to support K1 USB 2.0 PHY driver. This driver takes care of
 	  enabling and clock setup and will be used by K1 udc/ehci/otg driver.
+
+config PHY_SPACEMIT_K1_COMBPHY
+	tristate "SpacemiT K1 PCIe/USB3 combo PHY support"
+	depends on OF
+	select GENERIC_PHY
+	default ARCH_SPACEMIT && USB_DWC3_SPACEMIT
+	help
+	  USB3/PCIe Combo PHY Support for SpacemiT K1 SoC
diff --git a/drivers/phy/spacemit/Makefile b/drivers/phy/spacemit/Makefile
index fec0b425a948541b39b814caef0b05e1e002d92f..1fd0c65f2c5cd10ea2f70e43e62c70588d1ffae9 100644
--- a/drivers/phy/spacemit/Makefile
+++ b/drivers/phy/spacemit/Makefile
@@ -1,2 +1,3 @@
 # SPDX-License-Identifier: GPL-2.0-only
+obj-$(CONFIG_PHY_SPACEMIT_K1_COMBPHY)	+= phy-k1-combphy.o
 obj-$(CONFIG_PHY_SPACEMIT_K1_USB2)		+= phy-k1-usb2.o
diff --git a/drivers/phy/spacemit/phy-k1-combphy.c b/drivers/phy/spacemit/phy-k1-combphy.c
new file mode 100644
index 0000000000000000000000000000000000000000..a4b6e77fc2b4eb5d2c45d4e76294083509a3fc9d
--- /dev/null
+++ b/drivers/phy/spacemit/phy-k1-combphy.c
@@ -0,0 +1,229 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Spacemit K1 PCIE/USB3 PHY driver
+ *
+ * Copyright (C) 2025 SpacemiT (Hangzhou) Technology Co. Ltd
+ * Copyright (C) 2025 Ze Huang <huangze@xxxxxxxxxxx>
+ */
+
+#include <dt-bindings/phy/phy.h>
+#include <linux/clk.h>
+#include <linux/iopoll.h>
+#include <linux/phy/phy.h>
+#include <linux/platform_device.h>
+#include <linux/reset.h>
+#include <linux/usb/of.h>
+
+#define COMBPHY_USB_REG1	0x68
+#define  COMBPHY_USB_REG1_VAL	0x00
+#define COMBPHY_USB_REG2	0x48
+#define  COMBPHY_USB_REG2_VAL	0x603a2276
+#define COMBPHY_USB_REG3	0x08
+#define  COMBPHY_USB_REG3_VAL	0x97c
+#define COMBPHY_USB_REG4	0x18
+#define  COMBPHY_USB_REG4_VAL	0x00
+#define COMBPHY_USB_PLL_REG	0x08
+#define  COMBPHY_USB_PLL_MASK	0x01
+#define  COMBPHY_USB_PLL_VAL	0x01
+
+#define COMBPHY_MODE_SEL	BIT(3)
+#define COMBPHY_WAIT_TIMEOUT	1000
+
+struct spacemit_combphy_priv {
+	struct device *dev;
+	struct phy *phy;
+	struct reset_control *phy_rst;
+	void __iomem *phy_ctrl;
+	void __iomem *phy_sel;
+	u8 type;
+};
+
+static void spacemit_reg_update(void __iomem *reg, u32 offset, u32 mask, u32 val)
+{
+	u32 tmp;
+
+	tmp = readl(reg + offset);
+	tmp = (tmp & ~(mask)) | val;
+	writel(tmp, reg + offset);
+}
+
+static int spacemit_combphy_wait_ready(struct spacemit_combphy_priv *priv,
+				       u32 offset, u32 mask, u32 val)
+{
+	u32 reg_val;
+	int ret = 0;
+
+	ret = read_poll_timeout(readl, reg_val, (reg_val & mask) == val,
+				1000, COMBPHY_WAIT_TIMEOUT * 1000, false,
+				priv->phy_ctrl + offset);
+
+	return ret;
+}
+
+static int spacemit_combphy_set_mode(struct spacemit_combphy_priv *priv)
+{
+	int ret = 0;
+
+	switch (priv->type) {
+	case PHY_TYPE_USB3:
+		spacemit_reg_update(priv->phy_sel, 0, 0, COMBPHY_MODE_SEL);
+		break;
+	default:
+		dev_err(priv->dev, "PHY type %x not supported\n", priv->type);
+		ret = -EINVAL;
+		break;
+	}
+
+	return ret;
+}
+
+static int spacemit_combphy_init_usb(struct spacemit_combphy_priv *priv)
+{
+	void __iomem *base = priv->phy_ctrl;
+	int ret;
+
+	writel(COMBPHY_USB_REG1_VAL, base + COMBPHY_USB_REG1);
+	writel(COMBPHY_USB_REG2_VAL, base + COMBPHY_USB_REG2);
+	writel(COMBPHY_USB_REG3_VAL, base + COMBPHY_USB_REG3);
+	writel(COMBPHY_USB_REG4_VAL, base + COMBPHY_USB_REG4);
+
+	ret = spacemit_combphy_wait_ready(priv, COMBPHY_USB_PLL_REG,
+					  COMBPHY_USB_PLL_MASK,
+					  COMBPHY_USB_PLL_VAL);
+	if (ret)
+		dev_err(priv->dev, "USB3 PHY init timeout!\n");
+
+	return ret;
+}
+
+static int spacemit_combphy_init(struct phy *phy)
+{
+	struct spacemit_combphy_priv *priv = phy_get_drvdata(phy);
+	int ret;
+
+	ret = spacemit_combphy_set_mode(priv);
+	if (ret) {
+		dev_err(priv->dev, "failed to set mode for PHY type %x\n",
+			priv->type);
+		goto out;
+	}
+
+	ret = reset_control_deassert(priv->phy_rst);
+	if (ret) {
+		dev_err(priv->dev, "failed to deassert rst\n");
+		goto err_rst;
+	}
+
+	switch (priv->type) {
+	case PHY_TYPE_USB3:
+		ret = spacemit_combphy_init_usb(priv);
+		break;
+	default:
+		dev_err(priv->dev, "PHY type %x not supported\n", priv->type);
+		ret = -EINVAL;
+		break;
+	}
+
+	if (ret)
+		goto err_rst;
+
+	return 0;
+
+err_rst:
+	reset_control_assert(priv->phy_rst);
+out:
+	return ret;
+}
+
+static int spacemit_combphy_exit(struct phy *phy)
+{
+	struct spacemit_combphy_priv *priv = phy_get_drvdata(phy);
+
+	reset_control_assert(priv->phy_rst);
+
+	return 0;
+}
+
+static struct phy *spacemit_combphy_xlate(struct device *dev,
+					  const struct of_phandle_args *args)
+{
+	struct spacemit_combphy_priv *priv = dev_get_drvdata(dev);
+
+	if (args->args_count != 1) {
+		dev_err(dev, "invalid number of arguments\n");
+		return ERR_PTR(-EINVAL);
+	}
+
+	if (priv->type != PHY_NONE && priv->type != args->args[0])
+		dev_warn(dev, "PHY type %d is selected to override %d\n",
+			 args->args[0], priv->type);
+
+	priv->type = args->args[0];
+
+	if (args->args_count > 1)
+		dev_dbg(dev, "combo phy idx: %d selected",  args->args[1]);
+
+	return priv->phy;
+}
+
+static const struct phy_ops spacemit_combphy_ops = {
+	.init = spacemit_combphy_init,
+	.exit = spacemit_combphy_exit,
+	.owner = THIS_MODULE,
+};
+
+static int spacemit_combphy_probe(struct platform_device *pdev)
+{
+	struct spacemit_combphy_priv *priv;
+	struct phy_provider *phy_provider;
+	struct device *dev = &pdev->dev;
+
+	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	priv->phy_ctrl = devm_platform_ioremap_resource_byname(pdev, "phy_ctrl");
+	if (IS_ERR(priv->phy_ctrl))
+		return PTR_ERR(priv->phy_ctrl);
+
+	priv->phy_sel = devm_platform_ioremap_resource_byname(pdev, "phy_sel");
+	if (IS_ERR(priv->phy_sel))
+		return PTR_ERR(priv->phy_sel);
+
+	priv->type = PHY_NONE;
+	priv->dev = dev;
+
+	priv->phy_rst = devm_reset_control_get(dev, NULL);
+	if (IS_ERR(priv->phy_rst))
+		return dev_err_probe(dev, PTR_ERR(priv->phy_rst),
+				     "failed to get phy reset\n");
+
+	priv->phy = devm_phy_create(dev, NULL, &spacemit_combphy_ops);
+	if (IS_ERR(priv->phy))
+		return dev_err_probe(dev, PTR_ERR(priv->phy),
+				     "failed to create combphy\n");
+
+	dev_set_drvdata(dev, priv);
+	phy_set_drvdata(priv->phy, priv);
+	phy_provider = devm_of_phy_provider_register(dev, spacemit_combphy_xlate);
+
+	return PTR_ERR_OR_ZERO(phy_provider);
+}
+
+static const struct of_device_id spacemit_combphy_of_match[] = {
+	{ .compatible = "spacemit,k1-combphy", },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, spacemit_combphy_of_match);
+
+static struct platform_driver spacemit_combphy_driver = {
+	.probe	= spacemit_combphy_probe,
+	.driver = {
+		.name = "spacemit-k1-combphy",
+		.of_match_table = spacemit_combphy_of_match,
+	},
+};
+module_platform_driver(spacemit_combphy_driver);
+
+MODULE_DESCRIPTION("Spacemit PCIE/USB3.0 COMBO PHY driver");
+MODULE_LICENSE("GPL");

-- 
2.49.0