Re: [PATCH v2 2/2] usb: cdns3: Add TI specific wrapper driver
From: Peter Chen
Date: Mon Oct 21 2019 - 22:21:19 EST
On 19-10-21 16:13:05, Roger Quadros wrote:
> 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..5541cba71965
> --- /dev/null
> +++ b/drivers/usb/cdns3/cdns3-ti.c
> @@ -0,0 +1,236 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/**
> + * cdns_ti-ti.c - TI specific Glue layer for Cadence USB Controller
cdns3-ti.c
> + *
> + * Copyright (C) 2019 Texas Instruments Incorporated - https://eur01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.ti.com&data=02%7C01%7Cpeter.chen%40nxp.com%7C94aad23d5a294c5cdaf808d75628931c%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0%7C0%7C637072604595033025&sdata=Lye5SayAKcqAMaNGbZ%2Fq5OkUZ8IsWMVgGmeh8IhA69M%3D&reserved=0
> + */
> +
> +#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;
> + }
Why you don't enable runtime pm at the end of probe?
Peter
> +
> + /* 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");
> --
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>
--
Thanks,
Peter Chen