RE: [PATCH v3 2/2] usb: cdns3: Add TI specific wrapper driver

From: Pawel Laszczak
Date: Mon Oct 28 2019 - 05:07:18 EST


Hi,


Reviewed-by: Pawel Laszczak <pawell@xxxxxxxxxxx>

Regards,
Pawel,

>
>
>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 | 236 +++++++++++++++++++++++++++++++++++
>
> 3 files changed, 247 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..89620e40023f
>
>--- /dev/null
>
>+++ b/drivers/usb/cdns3/cdns3-ti.c
>
>@@ -0,0 +1,236 @@
>
>+// SPDX-License-Identifier: GPL-2.0
>
>+/**
>
>+ * cdns3-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=H6841QR1j9qs7DWnJfSzVFshZ-g7qZy7fYvO-sqqggo&s=eew1XA1kWdUhRDB8F-fyN96g8nJmTH3GVOk8PGoc1Iw&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 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, "ref");
>
>+ 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");
>
>+ 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 default modestrap */
>
>+ reg |= USBSS_W1_MODESTRAP_SEL;
>
>+ reg &= ~USBSS_W1_MODESTRAP_MASK;
>
>+ reg |= USBSS_MODESTRAP_MODE_NONE << 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");
>
>--
>
>Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki.
>
>Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki
>
>