usb: cdns3: Add StarFive JH7110 USB driver

Adds Specific Glue layer to support USB peripherals on
StarFive JH7110 SoC.
There is a Cadence USB3 core for JH7110 SoCs, the cdns
core is the child of this USB wrapper module device.

Signed-off-by: Minda Chen <[e-mail]>
Acked-by: Peter Chen <[e-mail]>
Reviewed-by: Roger Quadros <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

MAINTAINERS

···
 F:	drivers/reset/starfive/reset-starfive-jh71*
 F:	include/dt-bindings/reset/starfive?jh71*.h
 
+STARFIVE JH71X0 USB DRIVERS
+M:	Minda Chen <[e-mail]>
+S:	Maintained
+F:	Documentation/devicetree/bindings/usb/starfive,jh7110-usb.yaml
+F:	drivers/usb/cdns3/cdns3-starfive.c
+
 STARFIVE JH71XX PMU CONTROLLER DRIVER
 M:	Walker Chen <[e-mail]>
 S:	Supported

drivers/usb/cdns3/Kconfig

···
 
 	  For example, imx8qm and imx8qxp.
 
+config USB_CDNS3_STARFIVE
+	tristate "Cadence USB3 support on StarFive SoC platforms"
+	depends on ARCH_STARFIVE || COMPILE_TEST
+	help
+	  Say 'Y' or 'M' here if you are building for StarFive SoCs
+	  platforms that contain Cadence USB3 controller core.
+
+	  e.g. JH7110.
+
+	  If you choose to build this driver as module it will
+	  be dynamically linked and module will be called cdns3-starfive.ko
 endif
 
 if USB_CDNS_SUPPORT

drivers/usb/cdns3/Makefile

···
 obj-$(CONFIG_USB_CDNS3_PCI_WRAP)		+= cdns3-pci-wrap.o
 obj-$(CONFIG_USB_CDNS3_TI)			+= cdns3-ti.o
 obj-$(CONFIG_USB_CDNS3_IMX)			+= cdns3-imx.o
+obj-$(CONFIG_USB_CDNS3_STARFIVE)		+= cdns3-starfive.o
 
 cdnsp-udc-pci-y					:= cdnsp-pci.o
 

drivers/usb/cdns3/cdns3-starfive.c

···
+// SPDX-License-Identifier: GPL-2.0
+/**
+ * cdns3-starfive.c - StarFive specific Glue layer for Cadence USB Controller
+ *
+ * Copyright (C) 2023 StarFive Technology Co., Ltd.
+ *
+ * Author:	Minda Chen <[e-mail]>
+ */
+
+#include <linux/bits.h>
+#include <linux/clk.h>
+#include <linux/module.h>
+#include <linux/mfd/syscon.h>
+#include <linux/kernel.h>
+#include <linux/platform_device.h>
+#include <linux/io.h>
+#include <linux/of_platform.h>
+#include <linux/reset.h>
+#include <linux/regmap.h>
+#include <linux/usb/otg.h>
+#include "core.h"
+
+#define USB_STRAP_HOST			BIT(17)
+#define USB_STRAP_DEVICE		BIT(18)
+#define USB_STRAP_MASK			GENMASK(18, 16)
+
+#define USB_SUSPENDM_HOST		BIT(19)
+#define USB_SUSPENDM_MASK		BIT(19)
+
+#define USB_MISC_CFG_MASK		GENMASK(23, 20)
+#define USB_SUSPENDM_BYPS		BIT(20)
+#define USB_PLL_EN			BIT(22)
+#define USB_REFCLK_MODE			BIT(23)
+
+struct cdns_starfive {
+	struct device *dev;
+	struct regmap *stg_syscon;
+	struct reset_control *resets;
+	struct clk_bulk_data *clks;
+	int num_clks;
+	u32 stg_usb_mode;
+};
+
+static void cdns_mode_init(struct platform_device *pdev,
+			   struct cdns_starfive *data)
+{
+	enum usb_dr_mode mode;
+
+	regmap_update_bits(data->stg_syscon, data->stg_usb_mode,
+			   USB_MISC_CFG_MASK,
+			   USB_SUSPENDM_BYPS | USB_PLL_EN | USB_REFCLK_MODE);
+
+	/* dr mode setting */
+	mode = usb_get_dr_mode(&pdev->dev);
+
+	switch (mode) {
+	case USB_DR_MODE_HOST:
+		regmap_update_bits(data->stg_syscon,
+				   data->stg_usb_mode,
+				   USB_STRAP_MASK,
+				   USB_STRAP_HOST);
+		regmap_update_bits(data->stg_syscon,
+				   data->stg_usb_mode,
+				   USB_SUSPENDM_MASK,
+				   USB_SUSPENDM_HOST);
+		break;
+
+	case USB_DR_MODE_PERIPHERAL:
+		regmap_update_bits(data->stg_syscon, data->stg_usb_mode,
+				   USB_STRAP_MASK, USB_STRAP_DEVICE);
+		regmap_update_bits(data->stg_syscon, data->stg_usb_mode,
+				   USB_SUSPENDM_MASK, 0);
+		break;
+	default:
+		break;
+	}
+}
+
+static int cdns_clk_rst_init(struct cdns_starfive *data)
+{
+	int ret;
+
+	ret = clk_bulk_prepare_enable(data->num_clks, data->clks);
+	if (ret)
+		return dev_err_probe(data->dev, ret,
+				     "failed to enable clocks\n");
+
+	ret = reset_control_deassert(data->resets);
+	if (ret) {
+		dev_err(data->dev, "failed to reset clocks\n");
+		goto err_clk_init;
+	}
+
+	return ret;
+
+err_clk_init:
+	clk_bulk_disable_unprepare(data->num_clks, data->clks);
+	return ret;
+}
+
+static void cdns_clk_rst_deinit(struct cdns_starfive *data)
+{
+	reset_control_assert(data->resets);
+	clk_bulk_disable_unprepare(data->num_clks, data->clks);
+}
+
+static int cdns_starfive_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct cdns_starfive *data;
+	unsigned int args;
+	int ret;
+
+	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	data->dev = dev;
+
+	data->stg_syscon =
+		syscon_regmap_lookup_by_phandle_args(pdev->dev.of_node,
+						     "starfive,stg-syscon", 1, &args);
+
+	if (IS_ERR(data->stg_syscon))
+		return dev_err_probe(dev, PTR_ERR(data->stg_syscon),
+				     "Failed to parse starfive,stg-syscon\n");
+
+	data->stg_usb_mode = args;
+
+	data->num_clks = devm_clk_bulk_get_all(data->dev, &data->clks);
+	if (data->num_clks < 0)
+		return dev_err_probe(data->dev, -ENODEV,
+				     "Failed to get clocks\n");
+
+	data->resets = devm_reset_control_array_get_exclusive(data->dev);
+	if (IS_ERR(data->resets))
+		return dev_err_probe(data->dev, PTR_ERR(data->resets),
+				     "Failed to get resets");
+
+	cdns_mode_init(pdev, data);
+	ret = cdns_clk_rst_init(data);
+	if (ret)
+		return ret;
+
+	ret = of_platform_populate(dev->of_node, NULL, NULL, dev);
+	if (ret) {
+		dev_err(dev, "Failed to create children\n");
+		cdns_clk_rst_deinit(data);
+		return ret;
+	}
+
+	device_set_wakeup_capable(dev, true);
+	pm_runtime_set_active(dev);
+	pm_runtime_enable(dev);
+	platform_set_drvdata(pdev, data);
+
+	return 0;
+}
+
+static int cdns_starfive_remove_core(struct device *dev, void *c)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+
+	platform_device_unregister(pdev);
+
+	return 0;
+}
+
+static int cdns_starfive_remove(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct cdns_starfive *data = dev_get_drvdata(dev);
+
+	pm_runtime_get_sync(dev);
+	device_for_each_child(dev, NULL, cdns_starfive_remove_core);
+
+	pm_runtime_disable(dev);
+	pm_runtime_put_noidle(dev);
+	cdns_clk_rst_deinit(data);
+	platform_set_drvdata(pdev, NULL);
+
+	return 0;
+}
+
+#ifdef CONFIG_PM
+static int cdns_starfive_runtime_resume(struct device *dev)
+{
+	struct cdns_starfive *data = dev_get_drvdata(dev);
+
+	return clk_bulk_prepare_enable(data->num_clks, data->clks);
+}
+
+static int cdns_starfive_runtime_suspend(struct device *dev)
+{
+	struct cdns_starfive *data = dev_get_drvdata(dev);
+
+	clk_bulk_disable_unprepare(data->num_clks, data->clks);
+
+	return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int cdns_starfive_resume(struct device *dev)
+{
+	struct cdns_starfive *data = dev_get_drvdata(dev);
+
+	return cdns_clk_rst_init(data);
+}
+
+static int cdns_starfive_suspend(struct device *dev)
+{
+	struct cdns_starfive *data = dev_get_drvdata(dev);
+
+	cdns_clk_rst_deinit(data);
+
+	return 0;
+}
+#endif
+#endif
+
+static const struct dev_pm_ops cdns_starfive_pm_ops = {
+	SET_RUNTIME_PM_OPS(cdns_starfive_runtime_suspend,
+			   cdns_starfive_runtime_resume, NULL)
+	SET_SYSTEM_SLEEP_PM_OPS(cdns_starfive_suspend, cdns_starfive_resume)
+};
+
+static const struct of_device_id cdns_starfive_of_match[] = {
+	{ .compatible = "starfive,jh7110-usb", },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, cdns_starfive_of_match);
+
+static struct platform_driver cdns_starfive_driver = {
+	.probe		= cdns_starfive_probe,
+	.remove		= cdns_starfive_remove,
+	.driver		= {
+		.name	= "cdns3-starfive",
+		.of_match_table	= cdns_starfive_of_match,
+		.pm	= &cdns_starfive_pm_ops,
+	},
+};
+module_platform_driver(cdns_starfive_driver);
+
+MODULE_ALIAS("platform:cdns3-starfive");
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("Cadence USB3 StarFive Glue Layer");