From: Joey Lu <a0987203069@gmail•com>
To: Vinod Koul <vkoul@kernel•org>,
Neil Armstrong <neil.armstrong@linaro•org>
Cc: Rob Herring <robh@kernel•org>,
Krzysztof Kozlowski <krzk+dt@kernel•org>,
Conor Dooley <conor+dt@kernel•org>,
Jacky Huang <ychuang3@nuvoton•com>,
Shan-Chun Hung <schung@nuvoton•com>,
linux-phy@lists•infradead.org, devicetree@vger•kernel.org,
linux-arm-kernel@lists•infradead.org,
linux-kernel@vger•kernel.org, Joey Lu <a0987203069@gmail•com>
Subject: [PATCH 2/2] phy: nuvoton: Add MA35D1 USB2 OTG PHY driver
Date: Thu, 4 Jun 2026 18:12:20 +0800 [thread overview]
Message-ID: <20260604101220.1092822-3-a0987203069@gmail.com> (raw)
In-Reply-To: <20260604101220.1092822-1-a0987203069@gmail.com>
Add a PHY driver for the USB 2.0 PHYs in the Nuvoton MA35D1 SoC,
intended for use with the EHCI and OHCI host controllers.
The MA35D1 SoC has two USB ports:
- USB0: an OTG port shared between a DWC2 gadget controller and
EHCI0/OHCI0 host controllers. A hardware mux automatically routes
the physical USB0 signals to the appropriate controller based on the
USB ID pin state. The DWC2 IP is device-only in hardware,
so host-mode operation on USB0 is handled entirely by EHCI0/OHCI0.
- USB1: a dedicated host-only port served by EHCI1/OHCI1.
The driver implements:
- Power-On Reset sequence with a guard that skips re-initialization if
the PHY is already operational. This protects PHY0 when the DWC2
gadget driver has already run its own init before EHCI0 probes.
- Optional resistor calibration trim via nuvoton,rcalcode.
- Optional over-current detect polarity via nuvoton,oc-active-high.
- For PHY0 only: a USB role switch that exposes the hardware ID pin
state (PWRONOTP[16]).
Signed-off-by: Joey Lu <a0987203069@gmail•com>
---
drivers/phy/nuvoton/Kconfig | 15 ++
drivers/phy/nuvoton/Makefile | 1 +
drivers/phy/nuvoton/phy-ma35d1-otg.c | 264 +++++++++++++++++++++++++++
3 files changed, 280 insertions(+)
create mode 100644 drivers/phy/nuvoton/phy-ma35d1-otg.c
diff --git a/drivers/phy/nuvoton/Kconfig b/drivers/phy/nuvoton/Kconfig
index d02cae2db315..5fdd13f841e7 100644
--- a/drivers/phy/nuvoton/Kconfig
+++ b/drivers/phy/nuvoton/Kconfig
@@ -10,3 +10,18 @@ config PHY_MA35_USB
help
Enable this to support the USB2.0 PHY on the Nuvoton MA35
series SoCs.
+
+config PHY_MA35_USB_OTG
+ tristate "Nuvoton MA35 USB2.0 OTG PHY driver"
+ depends on ARCH_MA35 || COMPILE_TEST
+ depends on OF
+ select GENERIC_PHY
+ select MFD_SYSCON
+ select USB_ROLE_SWITCH
+ help
+ Enable this to support the USB2.0 OTG PHY on the Nuvoton MA35
+ series SoCs. This driver handles PHY initialization for the
+ EHCI/OHCI host controllers, including per-PHY power-on reset,
+ resistor calibration trim, and over-current polarity
+ configuration. For the OTG port (PHY0), it also monitors the
+ USB ID pin and registers a USB role switch.
diff --git a/drivers/phy/nuvoton/Makefile b/drivers/phy/nuvoton/Makefile
index 2937e3921898..3ecd76f35d7c 100644
--- a/drivers/phy/nuvoton/Makefile
+++ b/drivers/phy/nuvoton/Makefile
@@ -1,3 +1,4 @@
# SPDX-License-Identifier: GPL-2.0
obj-$(CONFIG_PHY_MA35_USB) += phy-ma35d1-usb2.o
+obj-$(CONFIG_PHY_MA35_USB_OTG) += phy-ma35d1-otg.o
diff --git a/drivers/phy/nuvoton/phy-ma35d1-otg.c b/drivers/phy/nuvoton/phy-ma35d1-otg.c
new file mode 100644
index 000000000000..53bc6ddf755e
--- /dev/null
+++ b/drivers/phy/nuvoton/phy-ma35d1-otg.c
@@ -0,0 +1,264 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Nuvoton MA35D1 USB 2.0 OTG PHY driver
+ *
+ * PHY0 (USB0) is shared between DWC2 gadget and EHCI0/OHCI0 host
+ * controllers. The hardware mux switches automatically via the USB
+ * ID pin. PHY1 (USB1) is host-only.
+ *
+ * Copyright (C) 2026 Nuvoton Technology Corp.
+ */
+#include <linux/bitfield.h>
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/phy/phy.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/usb/role.h>
+
+#define MA35_SYS_PWRONOTP 0x04
+#define PWRONOTP_USBP0ID BIT(16)
+
+#define MA35_SYS_USBPMISCR 0x60
+#define USBPMISCR_PHY_POR(n) BIT(0 + (n) * 16)
+#define USBPMISCR_PHY_SUSPEND(n) BIT(1 + (n) * 16)
+#define USBPMISCR_PHY_COMN(n) BIT(2 + (n) * 16)
+#define USBPMISCR_PHY_HSTCKSTB(n) BIT(8 + (n) * 16)
+#define USBPMISCR_PHY_CK12MSTB(n) BIT(9 + (n) * 16)
+/* Mask for control bits (POR, SUSPEND, COMN) of one PHY */
+#define USBPMISCR_PHY_CTL_MASK(n) (0x7 << ((n) * 16))
+/* Host-mode ready: SUSPEND + HSTCKSTB + CK12MSTB */
+#define USBPMISCR_PHY_HOST_READY(n) (USBPMISCR_PHY_SUSPEND(n) | \
+ USBPMISCR_PHY_HSTCKSTB(n) | \
+ USBPMISCR_PHY_CK12MSTB(n))
+/* RCALCODE: 4-bit resistor trim at bits [15:12] (PHY0) or [31:28] (PHY1) */
+#define USBPMISCR_RCAL_SHIFT(n) (12 + (n) * 16)
+#define USBPMISCR_RCAL_MASK(n) GENMASK(USBPMISCR_RCAL_SHIFT(n) + 3, \
+ USBPMISCR_RCAL_SHIFT(n))
+
+#define MA35_SYS_MISCFCR0 0x70
+/* MISCFCR0[12]: USB host over-current detect polarity (shared, both ports) */
+#define MISCFCR0_UHOVRCURH BIT(12)
+
+struct ma35_otg_phy {
+ struct clk *clk;
+ struct device *dev;
+ struct regmap *sysreg;
+ unsigned int phy_idx;
+ struct usb_role_switch *role_sw;
+ enum usb_role cur_role;
+};
+
+static int ma35_otg_phy_init(struct phy *phy)
+{
+ struct ma35_otg_phy *p = phy_get_drvdata(phy);
+ unsigned int n = p->phy_idx;
+ u32 ready_mask = USBPMISCR_PHY_HOST_READY(n);
+ unsigned int val;
+ int ret;
+
+ regmap_read(p->sysreg, MA35_SYS_USBPMISCR, &val);
+ if ((val & ready_mask) == ready_mask)
+ return 0;
+
+ regmap_update_bits(p->sysreg, MA35_SYS_USBPMISCR,
+ USBPMISCR_PHY_CTL_MASK(n),
+ USBPMISCR_PHY_POR(n) | USBPMISCR_PHY_SUSPEND(n));
+ msleep(20);
+
+ regmap_update_bits(p->sysreg, MA35_SYS_USBPMISCR,
+ USBPMISCR_PHY_CTL_MASK(n),
+ USBPMISCR_PHY_SUSPEND(n));
+
+ ret = regmap_read_poll_timeout(p->sysreg, MA35_SYS_USBPMISCR, val,
+ (val & ready_mask) == ready_mask,
+ 10, 1000);
+ if (ret) {
+ dev_err(p->dev, "USB PHY%u clock not stable (USBPMISCR=0x%08x)\n",
+ n, val);
+ return ret;
+ }
+
+ return 0;
+}
+
+static int ma35_otg_phy_power_on(struct phy *phy)
+{
+ struct ma35_otg_phy *p = phy_get_drvdata(phy);
+
+ return clk_prepare_enable(p->clk);
+}
+
+static int ma35_otg_phy_power_off(struct phy *phy)
+{
+ struct ma35_otg_phy *p = phy_get_drvdata(phy);
+
+ clk_disable_unprepare(p->clk);
+ return 0;
+}
+
+static const struct phy_ops ma35_otg_phy_ops = {
+ .init = ma35_otg_phy_init,
+ .power_on = ma35_otg_phy_power_on,
+ .power_off = ma35_otg_phy_power_off,
+ .owner = THIS_MODULE,
+};
+
+static enum usb_role ma35_otg_read_id(struct ma35_otg_phy *p)
+{
+ unsigned int val;
+
+ regmap_read(p->sysreg, MA35_SYS_PWRONOTP, &val);
+ return (val & PWRONOTP_USBP0ID) ? USB_ROLE_HOST : USB_ROLE_DEVICE;
+}
+
+static int ma35_otg_role_sw_set(struct usb_role_switch *sw,
+ enum usb_role role)
+{
+ struct ma35_otg_phy *p = usb_role_switch_get_drvdata(sw);
+
+ p->cur_role = role;
+
+ return 0;
+}
+
+static enum usb_role ma35_otg_role_sw_get(struct usb_role_switch *sw)
+{
+ struct ma35_otg_phy *p = usb_role_switch_get_drvdata(sw);
+
+ return ma35_otg_read_id(p);
+}
+
+static int ma35_otg_role_switch_init(struct platform_device *pdev,
+ struct ma35_otg_phy *p)
+{
+ struct usb_role_switch_desc sw_desc = { };
+
+ p->cur_role = ma35_otg_read_id(p);
+
+ sw_desc.set = ma35_otg_role_sw_set;
+ sw_desc.get = ma35_otg_role_sw_get;
+ sw_desc.allow_userspace_control = true;
+ sw_desc.driver_data = p;
+ sw_desc.fwnode = dev_fwnode(&pdev->dev);
+
+ p->role_sw = usb_role_switch_register(&pdev->dev, &sw_desc);
+ if (IS_ERR(p->role_sw))
+ return dev_err_probe(&pdev->dev, PTR_ERR(p->role_sw),
+ "failed to register role switch\n");
+
+ return 0;
+}
+
+static void ma35_otg_role_switch_exit(struct ma35_otg_phy *p)
+{
+ if (!p->role_sw)
+ return;
+
+ usb_role_switch_unregister(p->role_sw);
+ p->role_sw = NULL;
+}
+
+static int ma35_otg_phy_probe(struct platform_device *pdev)
+{
+ struct phy_provider *provider;
+ struct ma35_otg_phy *p;
+ unsigned int sys_args[1];
+ struct phy *phy;
+ u32 rcalcode;
+ int ret;
+
+ p = devm_kzalloc(&pdev->dev, sizeof(*p), GFP_KERNEL);
+ if (!p)
+ return -ENOMEM;
+
+ p->dev = &pdev->dev;
+ platform_set_drvdata(pdev, p);
+
+ p->sysreg = syscon_regmap_lookup_by_phandle_args(pdev->dev.of_node,
+ "nuvoton,sys",
+ 1, sys_args);
+ if (IS_ERR(p->sysreg))
+ return dev_err_probe(&pdev->dev, PTR_ERR(p->sysreg),
+ "Failed to get SYS regmap\n");
+
+ p->phy_idx = sys_args[0];
+
+ if (p->phy_idx > 1)
+ return dev_err_probe(&pdev->dev, -EINVAL,
+ "invalid PHY index %u (must be 0 or 1)\n",
+ p->phy_idx);
+
+ p->clk = devm_clk_get(&pdev->dev, NULL);
+ if (IS_ERR(p->clk))
+ return dev_err_probe(&pdev->dev, PTR_ERR(p->clk),
+ "failed to get PHY clock\n");
+
+ if (!of_property_read_u32(pdev->dev.of_node, "nuvoton,rcalcode",
+ &rcalcode)) {
+ if (rcalcode > 15)
+ return dev_err_probe(&pdev->dev, -EINVAL,
+ "rcalcode %u out of range (0-15)\n",
+ rcalcode);
+ regmap_update_bits(p->sysreg, MA35_SYS_USBPMISCR,
+ USBPMISCR_RCAL_MASK(p->phy_idx),
+ rcalcode << USBPMISCR_RCAL_SHIFT(p->phy_idx));
+ }
+
+ if (of_property_read_bool(pdev->dev.of_node, "nuvoton,oc-active-high"))
+ regmap_update_bits(p->sysreg, MA35_SYS_MISCFCR0,
+ MISCFCR0_UHOVRCURH, MISCFCR0_UHOVRCURH);
+
+ phy = devm_phy_create(&pdev->dev, pdev->dev.of_node, &ma35_otg_phy_ops);
+ if (IS_ERR(phy))
+ return dev_err_probe(&pdev->dev, PTR_ERR(phy),
+ "Failed to create PHY\n");
+
+ phy_set_drvdata(phy, p);
+
+ provider = devm_of_phy_provider_register(&pdev->dev,
+ of_phy_simple_xlate);
+ if (IS_ERR(provider))
+ return dev_err_probe(&pdev->dev, PTR_ERR(provider),
+ "Failed to register PHY provider\n");
+
+ if (p->phy_idx == 0) {
+ ret = ma35_otg_role_switch_init(pdev, p);
+ if (ret)
+ return ret;
+ }
+
+ return 0;
+}
+
+static void ma35_otg_phy_remove(struct platform_device *pdev)
+{
+ struct ma35_otg_phy *p = platform_get_drvdata(pdev);
+
+ ma35_otg_role_switch_exit(p);
+}
+
+static const struct of_device_id ma35_otg_phy_of_match[] = {
+ { .compatible = "nuvoton,ma35d1-usb2-phy-otg" },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, ma35_otg_phy_of_match);
+
+static struct platform_driver ma35_otg_phy_driver = {
+ .probe = ma35_otg_phy_probe,
+ .remove = ma35_otg_phy_remove,
+ .driver = {
+ .name = "ma35d1-usb2-phy-otg",
+ .of_match_table = ma35_otg_phy_of_match,
+ },
+};
+module_platform_driver(ma35_otg_phy_driver);
+
+MODULE_DESCRIPTION("Nuvoton MA35D1 USB 2.0 OTG PHY driver");
+MODULE_AUTHOR("Joey Lu <a0987203069@gmail•com>");
+MODULE_LICENSE("GPL");
--
2.43.0
prev parent reply other threads:[~2026-06-04 10:12 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-06-04 10:12 [PATCH 0/2] phy: nuvoton: Add MA35D1 USB2 OTG PHY driver Joey Lu
2026-06-04 10:12 ` [PATCH 1/2] dt-bindings: phy: nuvoton: Add MA35D1 USB2 OTG PHY binding Joey Lu
2026-06-04 10:12 ` Joey Lu [this message]
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