[PATCH 2/2] phy: nuvoton: add new driver for the Nuvoton MA35 SoC USB 2.0 PHY

From: hpchen0
Date: Mon Jul 29 2024 - 02:16:02 EST


Nuvoton MA35 SoCs support DWC2 USB controller.
Add the driver to drive the USB 2.0 PHY transceivers.

Signed-off-by: hpchen0 <hpchen0nvt@xxxxxxxxx>
---
drivers/phy/Kconfig | 1 +
drivers/phy/Makefile | 1 +
drivers/phy/nuvoton/Kconfig | 13 +++
drivers/phy/nuvoton/Makefile | 3 +
drivers/phy/nuvoton/phy-ma35-usb2.c | 160 ++++++++++++++++++++++++++++
5 files changed, 178 insertions(+)
create mode 100644 drivers/phy/nuvoton/Kconfig
create mode 100644 drivers/phy/nuvoton/Makefile
create mode 100644 drivers/phy/nuvoton/phy-ma35-usb2.c

diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig
index dfab1c66b3e5..f73abff416be 100644
--- a/drivers/phy/Kconfig
+++ b/drivers/phy/Kconfig
@@ -95,6 +95,7 @@ source "drivers/phy/mediatek/Kconfig"
source "drivers/phy/microchip/Kconfig"
source "drivers/phy/motorola/Kconfig"
source "drivers/phy/mscc/Kconfig"
+source "drivers/phy/nuvoton/Kconfig"
source "drivers/phy/qualcomm/Kconfig"
source "drivers/phy/ralink/Kconfig"
source "drivers/phy/realtek/Kconfig"
diff --git a/drivers/phy/Makefile b/drivers/phy/Makefile
index 5fcbce5f9ab1..ebc399560da4 100644
--- a/drivers/phy/Makefile
+++ b/drivers/phy/Makefile
@@ -25,6 +25,7 @@ obj-y += allwinner/ \
microchip/ \
motorola/ \
mscc/ \
+ nuvoton/ \
qualcomm/ \
ralink/ \
realtek/ \
diff --git a/drivers/phy/nuvoton/Kconfig b/drivers/phy/nuvoton/Kconfig
new file mode 100644
index 000000000000..270ee2943287
--- /dev/null
+++ b/drivers/phy/nuvoton/Kconfig
@@ -0,0 +1,13 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# PHY drivers for Nuvoton MA35 platforms
+#
+config PHY_MA35_USB
+ tristate "Nuvoton MA35 USB2.0 PHY driver"
+ depends on ARCH_MA35 || COMPILE_TEST
+ depends on OF
+ select GENERIC_PHY
+ help
+ Enable this to support the USB2.0 PHY on the Nuvoton MA35
+ series SoCs.
+
diff --git a/drivers/phy/nuvoton/Makefile b/drivers/phy/nuvoton/Makefile
new file mode 100644
index 000000000000..85785e037d5f
--- /dev/null
+++ b/drivers/phy/nuvoton/Makefile
@@ -0,0 +1,3 @@
+# SPDX-License-Identifier: GPL-2.0
+
+obj-$(CONFIG_PHY_MA35_USB) += phy-ma35-usb2.o
diff --git a/drivers/phy/nuvoton/phy-ma35-usb2.c b/drivers/phy/nuvoton/phy-ma35-usb2.c
new file mode 100644
index 000000000000..061b31fcfbb1
--- /dev/null
+++ b/drivers/phy/nuvoton/phy-ma35-usb2.c
@@ -0,0 +1,160 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2024 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>
+
+/* USB PHY Miscellaneous Control Register */
+#define MA35_SYS_REG_USBPMISCR 0x60
+#define PHY0POR BIT(0) /* PHY Power-On Reset Control Bit */
+#define PHY0SUSPEND BIT(1) /* PHY Suspend; 0: suspend, 1: operaion */
+#define PHY0COMN BIT(2) /* PHY Common Block Power-Down Control */
+#define PHY0DEVCKSTB BIT(10) /* PHY 60 MHz UTMI clock stable bit */
+
+struct ma35_usb_phy {
+ struct clk *clk;
+ struct device *dev;
+ struct regmap *sysreg;
+};
+
+static int ma35_usb_phy_power_on(struct phy *phy)
+{
+ struct ma35_usb_phy *p_phy = phy_get_drvdata(phy);
+ unsigned long timeout;
+ unsigned int val;
+ int ret;
+
+ ret = clk_prepare_enable(p_phy->clk);
+ if (ret < 0) {
+ dev_err(p_phy->dev, "Failed to enable PHY clock: %d\n", ret);
+ return ret;
+ }
+
+ regmap_read(p_phy->sysreg, MA35_SYS_REG_USBPMISCR, &val);
+ if (val & PHY0SUSPEND) {
+ /*
+ * USB PHY0 is in operation mode already
+ * make sure USB PHY 60 MHz UTMI Interface Clock ready
+ */
+ timeout = jiffies + msecs_to_jiffies(200);
+ while (time_before(jiffies, timeout)) {
+ regmap_read(p_phy->sysreg, MA35_SYS_REG_USBPMISCR, &val);
+ if (val & PHY0DEVCKSTB)
+ return 0;
+ usleep_range(1000, 1500);
+ }
+ }
+
+ /*
+ * reset USB PHY0.
+ * wait until USB PHY0 60 MHz UTMI Interface Clock ready
+ */
+ regmap_update_bits(p_phy->sysreg, MA35_SYS_REG_USBPMISCR, 0x7, (PHY0POR | PHY0SUSPEND));
+ timeout = jiffies + msecs_to_jiffies(200);
+ while (time_before(jiffies, timeout)) {
+ regmap_read(p_phy->sysreg, MA35_SYS_REG_USBPMISCR, &val);
+ if (val & PHY0DEVCKSTB)
+ break;
+ usleep_range(1000, 1500);
+ }
+
+ /* make USB PHY0 enter operation mode */
+ regmap_update_bits(p_phy->sysreg, MA35_SYS_REG_USBPMISCR, 0x7, PHY0SUSPEND);
+
+ /* make sure USB PHY 60 MHz UTMI Interface Clock ready */
+ timeout = jiffies + msecs_to_jiffies(200);
+ while (time_before(jiffies, timeout)) {
+ regmap_read(p_phy->sysreg, MA35_SYS_REG_USBPMISCR, &val);
+ if (val & PHY0DEVCKSTB)
+ return 0;
+ usleep_range(1000, 1500);
+ }
+
+ dev_err(p_phy->dev, "Timed out waiting for PHY to power on\n");
+ ret = -ETIMEDOUT;
+
+ clk_disable_unprepare(p_phy->clk);
+ return ret;
+}
+
+static int ma35_usb_phy_power_off(struct phy *phy)
+{
+ struct ma35_usb_phy *p_phy = phy_get_drvdata(phy);
+
+ clk_disable_unprepare(p_phy->clk);
+ return 0;
+}
+
+static const struct phy_ops ma35_usb_phy_ops = {
+ .power_on = ma35_usb_phy_power_on,
+ .power_off = ma35_usb_phy_power_off,
+ .owner = THIS_MODULE,
+};
+
+static int ma35_usb_phy_probe(struct platform_device *pdev)
+{
+ struct phy_provider *provider;
+ struct ma35_usb_phy *p_phy;
+ const char *clkgate;
+ struct phy *phy;
+
+ p_phy = devm_kzalloc(&pdev->dev, sizeof(*p_phy), GFP_KERNEL);
+ if (!p_phy)
+ return -ENOMEM;
+
+ p_phy->dev = &pdev->dev;
+ platform_set_drvdata(pdev, p_phy);
+
+ p_phy->sysreg = syscon_regmap_lookup_by_phandle(p_phy->dev->of_node, "nuvoton,sys");
+ if (IS_ERR(p_phy->sysreg))
+ return dev_err_probe(&pdev->dev, PTR_ERR(p_phy->sysreg),
+ "Failed to get SYS registers\n");
+
+ /* enable clock */
+ of_property_read_string(p_phy->dev->of_node, "clock-enable", &clkgate);
+ p_phy->clk = devm_clk_get(p_phy->dev, clkgate);
+ if (IS_ERR(p_phy->clk))
+ return dev_err_probe(&pdev->dev, PTR_ERR(p_phy->clk),
+ "Failed to get usb_phy clock\n");
+
+ phy = devm_phy_create(p_phy->dev, NULL, &ma35_usb_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_phy);
+
+ provider = devm_of_phy_provider_register(p_phy->dev, of_phy_simple_xlate);
+ if (IS_ERR(provider))
+ return dev_err_probe(&pdev->dev, PTR_ERR(provider),
+ "Failed to register PHY provider\n");
+ return 0;
+}
+
+static const struct of_device_id ma35_usb_phy_of_match[] = {
+ { .compatible = "nuvoton,ma35-usb2-phy", },
+ { },
+};
+MODULE_DEVICE_TABLE(of, ma35_usb_phy_of_match);
+
+static struct platform_driver ma35_usb_phy_driver = {
+ .probe = ma35_usb_phy_probe,
+ .driver = {
+ .name = "ma35-usb2-phy",
+ .of_match_table = ma35_usb_phy_of_match,
+ },
+};
+module_platform_driver(ma35_usb_phy_driver);
+
+MODULE_DESCRIPTION("Nuvoton ma35 USB2.0 PHY driver");
+MODULE_AUTHOR("hpchen0nvt@xxxxxxxxx");
+MODULE_LICENSE("GPL");
--
2.25.1