RE: [PATCH 2/2] usb: cdns3: Add TI specific wrapper driver

[Pawel Laszczak]

Hi Roger,

>The J721e platform comes with 2 Cadence USB3 controller
>
>instances. This driver supports the TI specific wrapper
>
>on this platform.
>
>
>
>Signed-off-by: Roger Quadros <rogerq@xxxxxx>
>
>Signed-off-by: Sekhar Nori <nsekhar@xxxxxx>
>
>---
>
> drivers/usb/cdns3/Kconfig    |  10 ++
>
> drivers/usb/cdns3/Makefile   |   1 +
>
> drivers/usb/cdns3/cdns3-ti.c | 244 +++++++++++++++++++++++++++++++++++
>
> 3 files changed, 255 insertions(+)
>
> create mode 100644 drivers/usb/cdns3/cdns3-ti.c
>
>
>
>diff --git a/drivers/usb/cdns3/Kconfig b/drivers/usb/cdns3/Kconfig
>
>index d0331613a355..2a1e89d12ed9 100644
>
>--- a/drivers/usb/cdns3/Kconfig
>
>+++ b/drivers/usb/cdns3/Kconfig
>
>@@ -43,4 +43,14 @@ config USB_CDNS3_PCI_WRAP
>
> 	  If you choose to build this driver as module it will
>
> 	  be dynamically linked and module will be called cdns3-pci.ko
>
>
>
>+config USB_CDNS3_TI
>
>+	tristate "Cadence USB3 support on TI platforms"
>
>+	depends on ARCH_K3 || COMPILE_TEST
>
>+	default USB_CDNS3
>
>+	help
>
>+	  Say 'Y' or 'M' here if you are building for Texas Instruments
>
>+	  platforms that contain Cadence USB3 controller core.
>
>+
>
>+	  e.g. J721e.
>
>+
>
> endif
>
>diff --git a/drivers/usb/cdns3/Makefile b/drivers/usb/cdns3/Makefile
>
>index a703547350bb..948e6b88d1a9 100644
>
>--- a/drivers/usb/cdns3/Makefile
>
>+++ b/drivers/usb/cdns3/Makefile
>
>@@ -14,3 +14,4 @@ endif
>
> cdns3-$(CONFIG_USB_CDNS3_HOST)		+= host.o
>
>
>
> obj-$(CONFIG_USB_CDNS3_PCI_WRAP)	+= cdns3-pci-wrap.o
>
>+obj-$(CONFIG_USB_CDNS3_TI)		+= cdns3-ti.o
>
>diff --git a/drivers/usb/cdns3/cdns3-ti.c b/drivers/usb/cdns3/cdns3-ti.c
>
>new file mode 100644
>
>index 000000000000..7447f5fcbe64
>
>--- /dev/null
>
>+++ b/drivers/usb/cdns3/cdns3-ti.c
>
>@@ -0,0 +1,244 @@
>
>+// SPDX-License-Identifier: GPL-2.0
>
>+/**
>
>+ * cdns_ti-ti.c - TI specific Glue layer for Cadence USB Controller
>
>+ *
>
>+ * Copyright (C) 2019 Texas Instruments Incorporated - https://urldefense.proofpoint.com/v2/url?u=http-
>3A__www.ti.com&d=DwIBAg&c=aUq983L2pue2FqKFoP6PGHMJQyoJ7kl3s3GZ-_haXqY&r=e1OgxfvkL0qo9XO6fX1gscva-
>w03uSYC1nIyxl89-
>rI&m=cRVMFQ8EW2o1zPxOk40aNbOduH3ZSMTGs3Gjr6j7DIw&s=CX3YTCKJekxIRkpi36cPmm8eEH1NK7Ipaag0MVAL4cc&e=
>
>+ */
>
>+
>
>+#include <linux/bits.h>
>
>+#include <linux/clk.h>
>
>+#include <linux/module.h>
>
>+#include <linux/kernel.h>
>
>+#include <linux/interrupt.h>
>
>+#include <linux/platform_device.h>
>
>+#include <linux/dma-mapping.h>
>
>+#include <linux/io.h>
>
>+#include <linux/of_platform.h>
>
>+#include <linux/pm_runtime.h>
>
>+
>
>+/* USB Wrapper register offsets */
>
>+#define USBSS_PID		0x0
>
>+#define	USBSS_W1		0x4
>
>+#define USBSS_STATIC_CONFIG	0x8
>
>+#define USBSS_PHY_TEST		0xc
>
>+#define	USBSS_DEBUG_CTRL	0x10
>
>+#define	USBSS_DEBUG_INFO	0x14
>
>+#define	USBSS_DEBUG_LINK_STATE	0x18
>
>+#define	USBSS_DEVICE_CTRL	0x1c
>
>+
>
>+/* Wrapper 1 register bits */
>
>+#define USBSS_W1_PWRUP_RST		BIT(0)
>
>+#define USBSS_W1_OVERCURRENT_SEL	BIT(8)
>
>+#define USBSS_W1_MODESTRAP_SEL		BIT(9)
>
>+#define USBSS_W1_OVERCURRENT		BIT(16)
>
>+#define USBSS_W1_MODESTRAP_MASK		GENMASK(18, 17)
>
>+#define USBSS_W1_MODESTRAP_SHIFT	17
>
>+#define USBSS_W1_USB2_ONLY		BIT(19)
>
>+
>
>+/* Static config register bits */
>
>+#define USBSS1_STATIC_PLL_REF_SEL_MASK	GENMASK(8, 5)
>
>+#define USBSS1_STATIC_PLL_REF_SEL_SHIFT	5
>
>+#define USBSS1_STATIC_LOOPBACK_MODE_MASK	GENMASK(4, 3)
>
>+#define USBSS1_STATIC_LOOPBACK_MODE_SHIFT	3
>
>+#define USBSS1_STATIC_VBUS_SEL_MASK	GENMASK(2, 1)
>
>+#define USBSS1_STATIC_VBUS_SEL_SHIFT	1
>
>+#define USBSS1_STATIC_LANE_REVERSE	BIT(0)
>
>+
>
>+/* Modestrap modes */
>
>+enum modestrap_mode { USBSS_MODESTRAP_MODE_NONE,
>
>+		      USBSS_MODESTRAP_MODE_HOST,
>
>+		      USBSS_MODESTRAP_MODE_PERIPHERAL};
>
>+
>
>+struct cdns_ti {
>
>+	struct device *dev;
>
>+	void __iomem *usbss;
>
>+	int usb2_only:1;
>
>+	int vbus_divider:1;
>
>+	struct clk *usb2_refclk;
>
>+	struct clk *lpm_clk;
>
>+};
>
>+
>
>+static const int cdns_ti_rate_table[] = {	/* in KHZ */
>
>+	9600,
>
>+	10000,
>
>+	12000,
>
>+	19200,
>
>+	20000,
>
>+	24000,
>
>+	25000,
>
>+	26000,
>
>+	38400,
>
>+	40000,
>
>+	58000,
>
>+	50000,
>
>+	52000,
>
>+};
>
>+
>
>+static inline u32 cdns_ti_readl(struct cdns_ti *data, u32 offset)
>
>+{
>
>+	return readl(data->usbss + offset);
>
>+}
>
>+
>
>+static inline void cdns_ti_writel(struct cdns_ti *data, u32 offset, u32 value)
>
>+{
>
>+	writel(value, data->usbss + offset);
>
>+}
>
>+
>
>+static int cdns_ti_probe(struct platform_device *pdev)
>
>+{
>
>+	struct device *dev = &pdev->dev;
>
>+	struct device_node *node = pdev->dev.of_node;
>
>+	struct cdns_ti *data;
>
>+	struct resource	*res;
>
>+	int error;
>
>+	u32 reg;
>
>+	int modestrap_mode;
>
>+	int rate_code, i;
>
>+	unsigned long rate;
>
>+
>
>+	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
>
>+	if (!data)
>
>+		return -ENOMEM;
>
>+
>
>+	platform_set_drvdata(pdev, data);
>
>+
>
>+	data->dev = dev;
>
>+
>
>+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
>
>+	data->usbss = devm_ioremap_resource(dev, res);
>
>+	if (IS_ERR(data->usbss))
>
>+		return PTR_ERR(data->usbss);
>
>+
>
>+	data->usb2_refclk = devm_clk_get(dev, "usb2_refclk");
>
>+	if (IS_ERR(data->usb2_refclk)) {
>
>+		dev_err(dev, "can't get usb2_refclk\n");
>
>+		return PTR_ERR(data->usb2_refclk);
>
>+	}
>
>+
>
>+	data->lpm_clk = devm_clk_get(dev, "lpm_clk");
>
>+	if (IS_ERR(data->lpm_clk)) {
>
>+		dev_err(dev, "can't get lpm_clk\n");
>
>+		return PTR_ERR(data->lpm_clk);
>
>+	}
>
>+
>
>+	rate = clk_get_rate(data->usb2_refclk);
>
>+	rate /= 1000;	/* To KHz */
>
>+	for (i = 0; i < ARRAY_SIZE(cdns_ti_rate_table); i++) {
>
>+		if (cdns_ti_rate_table[i] == rate)
>
>+			break;
>
>+	}
>
>+
>
>+	if (i == ARRAY_SIZE(cdns_ti_rate_table)) {
>
>+		dev_err(dev, "unsupported usb2_refclk rate: %lu KHz\n", rate);
>
>+		return -EINVAL;
>
>+	}
>
>+
>
>+	rate_code = i;
>
>+
>
>+	pm_runtime_enable(dev);
>
>+	error = pm_runtime_get_sync(dev);
>
>+	if (error < 0) {
>
>+		dev_err(dev, "pm_runtime_get_sync failed: %d\n", error);
>
>+		goto err_get;
>
>+	}
>
>+
>
>+	/* assert RESET */
>
>+	reg = cdns_ti_readl(data, USBSS_W1);
>
>+	reg &= ~USBSS_W1_PWRUP_RST;
>
>+	cdns_ti_writel(data, USBSS_W1, reg);
>
>+
>
>+	/* set static config */
>
>+	reg = cdns_ti_readl(data, USBSS_STATIC_CONFIG);
>
>+	reg &= ~USBSS1_STATIC_PLL_REF_SEL_MASK;
>
>+	reg |= rate_code << USBSS1_STATIC_PLL_REF_SEL_SHIFT;
>
>+
>
>+	reg &= ~USBSS1_STATIC_VBUS_SEL_MASK;
>
>+	data->vbus_divider = device_property_read_bool(dev, "ti,vbus-divider");
>
>+	if (data->vbus_divider)
>
>+		reg |= 1 << USBSS1_STATIC_VBUS_SEL_SHIFT;
>
>+
>
>+	cdns_ti_writel(data, USBSS_STATIC_CONFIG, reg);
>
>+	reg = cdns_ti_readl(data, USBSS_STATIC_CONFIG);
>
>+
>
>+	/* set USB2_ONLY mode if requested */
>
>+	reg = cdns_ti_readl(data, USBSS_W1);
>
>+	data->usb2_only = device_property_read_bool(dev, "ti,usb2-only");
>
>+	if (data->usb2_only)
>
>+		reg |= USBSS_W1_USB2_ONLY;
>
>+
>
>+	/* set modestrap  */
>
>+	if (device_property_read_bool(dev, "ti,modestrap-host"))
>
>+		modestrap_mode = USBSS_MODESTRAP_MODE_HOST;
>
>+	else if (device_property_read_bool(dev, "ti,modestrap-peripheral"))
>
>+		modestrap_mode = USBSS_MODESTRAP_MODE_PERIPHERAL;
>
>+	else
>
>+		modestrap_mode = USBSS_MODESTRAP_MODE_NONE;
>
>+
>
>+	reg |= USBSS_W1_MODESTRAP_SEL;
>
>+	reg &= ~USBSS_W1_MODESTRAP_MASK;
>
>+	reg |= modestrap_mode << USBSS_W1_MODESTRAP_SHIFT;
>
>+	cdns_ti_writel(data, USBSS_W1, reg);
>
>+
>
>+	/* de-assert RESET */
>
>+	reg |= USBSS_W1_PWRUP_RST;
>
>+	cdns_ti_writel(data, USBSS_W1, reg);
>
>+
>
>+	error = of_platform_populate(node, NULL, NULL, dev);
>
>+	if (error) {
>
>+		dev_err(dev, "failed to create children: %d\n", error);
>
>+		goto err;
>
>+	}
>
>+
>
>+	return 0;
>
>+
>
>+err:
>
>+	pm_runtime_put_sync(data->dev);
>
>+err_get:
>
>+	pm_runtime_disable(data->dev);
>
>+
>
>+	return error;
>
>+}
>
>+
>
>+static int cdns_ti_remove_core(struct device *dev, void *c)
>
>+{
>
>+	struct platform_device *pdev = to_platform_device(dev);
>
>+
>
>+	platform_device_unregister(pdev);
>
>+
>
>+	return 0;
>
>+}
>
>+
>
>+static int cdns_ti_remove(struct platform_device *pdev)
>
>+{
>
>+	struct device *dev = &pdev->dev;
>
>+
>
>+	device_for_each_child(dev, NULL, cdns_ti_remove_core);
>
>+	pm_runtime_put_sync(dev);
>
>+	pm_runtime_disable(dev);
>
>+
>
>+	platform_set_drvdata(pdev, NULL);
>
>+
>
>+	return 0;
>
>+}
>
>+
>
>+static const struct of_device_id cdns_ti_of_match[] = {
>
>+	{ .compatible = "ti,j721e-usb", },
>
>+	{},
>
>+};
>
>+MODULE_DEVICE_TABLE(of, cdns_ti_of_match);
>
>+
>
>+static struct platform_driver cdns_ti_driver = {
>
>+	.probe		= cdns_ti_probe,
>
>+	.remove		= cdns_ti_remove,
>
>+	.driver		= {
>
>+		.name	= "cdns3-ti",
>
>+		.of_match_table	= cdns_ti_of_match,
>
>+	},
>
>+};
>
>+
>
>+module_platform_driver(cdns_ti_driver);
>
>+
>
>+MODULE_ALIAS("platform:cdns3-ti");
>
>+MODULE_AUTHOR("Roger Quadros <rogerq@xxxxxx>");
>
>+MODULE_LICENSE("GPL v2");
>
>+MODULE_DESCRIPTION("Cadence USB3 TI Glue Layer");
>


Reviewed-by: Pawel Laszczak <pawell@xxxxxxxxxxx>

Regards,
Pawel

>--
>
>Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki.
>
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