Hi Thinh,
>
> On Thu, Aug 24, 2023, Stanley Chang wrote:
> > Realtek DHC RTD SoCs integrate dwc3 IP and has some customizations to
> > support different generations of SoCs.
> >
> > The RTD1619b subclass SoC only supports USB 2.0 from dwc3. The driver
> > can set a maximum speed to support this. Add role switching function,
> > that can switch USB roles through other drivers, or switch USB roles
> > through user space through set /sys/class/usb_role/.
> >
> > Signed-off-by: Stanley Chang <stanley_chang@xxxxxxxxxxx>
> > ---
> > v4 to v5 change:
> > 1. Use enumeration and define usb_role uniformly instead of
> > dr_mode to avoid confusing dr_mode and usb_role.
> > 2. Split the register read and write to separate operations.
> > v3 to v4 change:
> > Get max-speed from dwc3 node.
> > Add the register set for pm control.
> > v2 to v3 change:
> > Remove the support_drd_mode of struct dwc3_rtk.
> > Remove unlink_usb3_port and disable_usb3_phy.
> > Disabled usb3 phy if the max speed is not super-speed.
> > v1 to v2 change:
> > Remove the code about the property realtek,enable-l4icg.
> > Select USB_ROLE_SWITCH in Kconfig.
> > Add dependency OF and ARCH_REALTEK in Kconfig.
> > ---
> > drivers/usb/dwc3/Kconfig | 11 +
> > drivers/usb/dwc3/Makefile | 1 +
> > drivers/usb/dwc3/dwc3-rtk.c | 478
> > ++++++++++++++++++++++++++++++++++++
> > 3 files changed, 490 insertions(+)
> > create mode 100644 drivers/usb/dwc3/dwc3-rtk.c
> >
> > diff --git a/drivers/usb/dwc3/Kconfig b/drivers/usb/dwc3/Kconfig index
> > 98efcbb76c88..5fc27b20df63 100644
> > --- a/drivers/usb/dwc3/Kconfig
> > +++ b/drivers/usb/dwc3/Kconfig
> > @@ -178,4 +178,15 @@ config USB_DWC3_OCTEON
> > Only the host mode is currently supported.
> > Say 'Y' or 'M' here if you have one such device.
> >
> > +config USB_DWC3_RTK
> > + tristate "Realtek DWC3 Platform Driver"
> > + depends on OF && ARCH_REALTEK
> > + default USB_DWC3
> > + select USB_ROLE_SWITCH
> > + help
> > + RTK DHC RTD SoCs with DesignWare Core USB3 IP inside,
> > + and IP Core configured for USB 2.0 and USB 3.0 in host
> > + or dual-role mode.
> > + Say 'Y' or 'M' if you have such device.
> > +
> > endif
> > diff --git a/drivers/usb/dwc3/Makefile b/drivers/usb/dwc3/Makefile
> > index fe1493d4bbe5..124eda2522d9 100644
> > --- a/drivers/usb/dwc3/Makefile
> > +++ b/drivers/usb/dwc3/Makefile
> > @@ -55,3 +55,4 @@ obj-$(CONFIG_USB_DWC3_QCOM) +=
> dwc3-qcom.o
> > obj-$(CONFIG_USB_DWC3_IMX8MP) +=
> dwc3-imx8mp.o
> > obj-$(CONFIG_USB_DWC3_XILINX) += dwc3-xilinx.o
> > obj-$(CONFIG_USB_DWC3_OCTEON) += dwc3-octeon.o
> > +obj-$(CONFIG_USB_DWC3_RTK) += dwc3-rtk.o
> > diff --git a/drivers/usb/dwc3/dwc3-rtk.c b/drivers/usb/dwc3/dwc3-rtk.c
> > new file mode 100644 index 000000000000..9d735d2646f7
> > --- /dev/null
> > +++ b/drivers/usb/dwc3/dwc3-rtk.c
> > @@ -0,0 +1,478 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +/*
> > + * dwc3-rtk.c - Realtek DWC3 Specific Glue layer
> > + *
> > + * Copyright (C) 2023 Realtek Semiconductor Corporation
> > + *
> > + */
> > +
> > +#include <linux/module.h>
> > +#include <linux/kernel.h>
> > +#include <linux/platform_device.h>
> > +#include <linux/of.h>
> > +#include <linux/of_platform.h>
> > +#include <linux/suspend.h>
> > +#include <linux/sys_soc.h>
> > +#include <linux/usb/otg.h>
> > +#include <linux/usb/of.h>
> > +#include <linux/usb/role.h>
> > +
> > +#include "core.h"
> > +
> > +#define WRAP_CTR_REG 0x0
> > +#define DISABLE_MULTI_REQ BIT(1)
> > +#define DESC_R2W_MULTI_DISABLE BIT(9) #define
> > +FORCE_PIPE3_PHY_STATUS_TO_0 BIT(13)
> > +
> > +#define WRAP_USB2_PHY_UTMI_REG 0x8
> > +#define TXHSVM_EN BIT(3)
> > +
> > +#define WRAP_PHY_PIPE_REG 0xC
> > +#define RESET_DISABLE_PIPE3_P0 BIT(0) #define
> > +CLOCK_ENABLE_FOR_PIPE3_PCLK BIT(1)
> > +
> > +#define WRAP_USB_HMAC_CTR0_REG 0x60
> > +#define U3PORT_DIS BIT(8)
> > +
> > +#define WRAP_USB2_PHY_REG 0x70
> > +#define USB2_PHY_EN_PHY_PLL_PORT0 BIT(12) #define
> > +USB2_PHY_EN_PHY_PLL_PORT1 BIT(13) #define USB2_PHY_SWITCH_MASK
> 0x707
> > +#define USB2_PHY_SWITCH_DEVICE 0x0 #define USB2_PHY_SWITCH_HOST
> 0x606
> > +
> > +#define WRAP_APHY_REG 0x128
> > +#define USB3_MBIAS_ENABLE BIT(1)
> > +
> > +/* pm control */
> > +#define WRAP_USB_DBUS_PWR_CTRL_REG 0x160 #define
> > +USB_DBUS_PWR_CTRL_REG 0x0 #define DBUS_PWR_CTRL_EN BIT(0)
> > +
> > +struct dwc3_rtk {
> > + struct device *dev;
> > + void __iomem *regs;
> > + size_t regs_size;
> > + void __iomem *pm_base;
> > +
> > + struct dwc3 *dwc;
> > +
> > + enum usb_role cur_role;
> > + struct usb_role_switch *role_switch; };
> > +
> > +static void switch_usb2_role(struct dwc3_rtk *rtk, enum usb_role
> > +role) {
> > + void __iomem *reg;
> > + int val;
> > +
> > + reg = rtk->regs + WRAP_USB2_PHY_REG;
> > + val = ~USB2_PHY_SWITCH_MASK & readl(reg);
> > +
> > + switch (role) {
> > + case USB_ROLE_DEVICE:
> > + writel(USB2_PHY_SWITCH_DEVICE | val, reg);
> > + break;
> > + case USB_ROLE_HOST:
> > + writel(USB2_PHY_SWITCH_HOST | val, reg);
> > + break;
> > + default:
> > + dev_dbg(rtk->dev, "%s: role=%d\n", __func__, role);
> > + break;
> > + }
> > +}
> > +
> > +static void switch_dwc3_role(struct dwc3_rtk *rtk, enum usb_role
> > +role) {
> > + if (!rtk->dwc->role_sw)
> > + goto out;
>
> Just return early here.
>
> > +
> > + usb_role_switch_set_role(rtk->dwc->role_sw, role);
> > +
> > +out:
> > + return;
> > +}
> > +
> > +static enum usb_role dwc3_rtk_get_role(struct dwc3_rtk *rtk) {
> > + enum usb_role role;
> > +
> > + role = rtk->cur_role;
> > +
> > + if (rtk->dwc && rtk->dwc->role_sw)
> > + role = usb_role_switch_get_role(rtk->dwc->role_sw);
> > + else
> > + dev_dbg(rtk->dev, "%s not usb_role_switch role=%d\n",
> > + __func__, role);
> > +
> > + return role;
> > +}
> > +
> > +static void dwc3_rtk_set_role(struct dwc3_rtk *rtk, enum usb_role
> > +role) {
> > + rtk->cur_role = role;
> > +
> > + switch_dwc3_role(rtk, role);
> > + mdelay(10);
> > + switch_usb2_role(rtk, role);
> > +}
> > +
> > +#if IS_ENABLED(CONFIG_USB_ROLE_SWITCH)
> > +static int dwc3_usb_role_switch_set(struct usb_role_switch *sw, enum
> > +usb_role role) {
> > + struct dwc3_rtk *rtk = usb_role_switch_get_drvdata(sw);
> > +
> > + dwc3_rtk_set_role(rtk, role);
> > +
> > + return 0;
> > +}
> > +
> > +static enum usb_role dwc3_usb_role_switch_get(struct usb_role_switch
> > +*sw) {
> > + struct dwc3_rtk *rtk = usb_role_switch_get_drvdata(sw);
> > +
> > + return dwc3_rtk_get_role(rtk);
> > +}
> > +
> > +static int dwc3_rtk_setup_role_switch(struct dwc3_rtk *rtk) {
> > + struct usb_role_switch_desc dwc3_role_switch = {NULL};
> > +
> > + dwc3_role_switch.name = strchrnul(dev_name(rtk->dev), '.') + 1;
>
> Would there be multiple instances of your device in the same setup?
You are right to be concerned, I should add address to avoid this.
> > + dwc3_role_switch.driver_data = rtk;
> > + dwc3_role_switch.allow_userspace_control = true;
> > + dwc3_role_switch.fwnode = dev_fwnode(rtk->dev);
> > + dwc3_role_switch.set = dwc3_usb_role_switch_set;
> > + dwc3_role_switch.get = dwc3_usb_role_switch_get;
> > + rtk->role_switch = usb_role_switch_register(rtk->dev,
> &dwc3_role_switch);
> > + if (IS_ERR(rtk->role_switch))
> > + return PTR_ERR(rtk->role_switch);
> > +
> > + return 0;
> > +}
> > +
> > +static int dwc3_rtk_remove_role_switch(struct dwc3_rtk *rtk) {
> > + if (rtk->role_switch)
> > + usb_role_switch_unregister(rtk->role_switch);
> > +
> > + rtk->role_switch = NULL;
> > +
> > + return 0;
> > +}
> > +#else
> > +#define dwc3_rtk_setup_role_switch(x) 0 #define
> > +dwc3_rtk_remove_role_switch(x) 0 #endif
> > +
> > +static const char *const speed_names[] = {
> > + [USB_SPEED_UNKNOWN] = "UNKNOWN",
> > + [USB_SPEED_LOW] = "low-speed",
> > + [USB_SPEED_FULL] = "full-speed",
> > + [USB_SPEED_HIGH] = "high-speed",
> > + [USB_SPEED_WIRELESS] = "wireless",
> > + [USB_SPEED_SUPER] = "super-speed",
> > + [USB_SPEED_SUPER_PLUS] = "super-speed-plus", };
> > +
> > +static enum usb_device_speed __get_dwc3_maximum_speed(struct
> > +device_node *np) {
> > + struct device_node *dwc3_np;
> > + const char *maximum_speed;
> > + int ret;
> > +
> > + dwc3_np = of_get_compatible_child(np, "snps,dwc3");
> > + if (!dwc3_np)
> > + return USB_SPEED_UNKNOWN;
> > +
> > + ret = of_property_read_string(dwc3_np, "maximum-speed",
> &maximum_speed);
> > + if (ret < 0)
> > + return USB_SPEED_UNKNOWN;
> > +
> > + ret = match_string(speed_names, ARRAY_SIZE(speed_names),
> > + maximum_speed);
> > +
> > + return (ret < 0) ? USB_SPEED_UNKNOWN : ret; }
> > +
> > +static int dwc3_rtk_init(struct dwc3_rtk *rtk) {
> > + struct device *dev = rtk->dev;
> > + void __iomem *reg;
> > + int val;
> > + enum usb_device_speed maximum_speed;
> > + const struct soc_device_attribute rtk_soc_kylin_a00[] = {
> > + { .family = "Realtek Kylin", .revision = "A00", },
> > + { /* empty */ } };
> > + const struct soc_device_attribute rtk_soc_hercules[] = {
> > + { .family = "Realtek Hercules", }, { /* empty */ } };
> > + const struct soc_device_attribute rtk_soc_thor[] = {
> > + { .family = "Realtek Thor", }, { /* empty */ } };
> > +
> > + if (soc_device_match(rtk_soc_kylin_a00)) {
> > + reg = rtk->regs + WRAP_CTR_REG;
> > + val = readl(reg);
> > + writel(DISABLE_MULTI_REQ | val, reg);
> > + dev_info(dev, "[bug fixed] 1295/1296 A00: add workaround
> to disable multiple request for D-Bus");
> > + }
> > +
> > + if (soc_device_match(rtk_soc_hercules)) {
> > + reg = rtk->regs + WRAP_USB2_PHY_REG;
> > + val = readl(reg);
> > + writel(USB2_PHY_EN_PHY_PLL_PORT1 | val, reg);
> > + dev_info(dev, "[bug fixed] 1395 add workaround to disable
> usb2 port 2 suspend!");
> > + }
> > +
> > + reg = rtk->regs + WRAP_USB2_PHY_UTMI_REG;
> > + val = readl(reg);
> > + writel(TXHSVM_EN | val, reg);
> > +
> > + maximum_speed = __get_dwc3_maximum_speed(dev->of_node);
> > + if (maximum_speed != USB_SPEED_UNKNOWN && maximum_speed
> <= USB_SPEED_HIGH) {
> > + if (soc_device_match(rtk_soc_thor)) {
> > + reg = rtk->regs + WRAP_USB_HMAC_CTR0_REG;
> > + val = readl(reg);
> > + writel(U3PORT_DIS | val, reg);
> > + } else {
> > + reg = rtk->regs + WRAP_CTR_REG;
> > + val = readl(reg);
> > + writel(FORCE_PIPE3_PHY_STATUS_TO_0 | val,
> reg);
> > +
> > + reg = rtk->regs + WRAP_PHY_PIPE_REG;
> > + val = ~CLOCK_ENABLE_FOR_PIPE3_PCLK &
> readl(reg);
> > + writel(RESET_DISABLE_PIPE3_P0 | val, reg);
> > +
> > + reg = rtk->regs +
> WRAP_USB_HMAC_CTR0_REG;
> > + val = readl(reg);
> > + writel(U3PORT_DIS | val, reg);
> > +
> > + reg = rtk->regs + WRAP_APHY_REG;
> > + val = readl(reg);
> > + writel(~USB3_MBIAS_ENABLE & val, reg);
> > +
> > + dev_info(rtk->dev, "%s: disable usb 3.0 phy\n",
> > + __func__);
>
> I think we should use dev_dbg here.
Okay
> > + }
> > + }
> > +
> > + reg = rtk->regs + WRAP_CTR_REG;
> > + val = readl(reg);
> > + writel(DESC_R2W_MULTI_DISABLE | val, reg);
> > +
> > + /* Set phy Dp/Dm initial state to host mode to avoid the Dp glitch */
> > + reg = rtk->regs + WRAP_USB2_PHY_REG;
> > + val = ~USB2_PHY_SWITCH_MASK & readl(reg);
> > + writel(USB2_PHY_SWITCH_HOST | val, reg);
> > +
> > + if (rtk->pm_base) {
> > + reg = rtk->pm_base + USB_DBUS_PWR_CTRL_REG;
> > + val = DBUS_PWR_CTRL_EN | readl(reg);
> > + writel(val, reg);
> > + }
> > +
> > + return 0;
> > +}
> > +
> > +static int dwc3_rtk_probe_dwc3_core(struct dwc3_rtk *rtk) {
> > + struct device *dev = rtk->dev;
> > + struct device_node *node = dev->of_node;
> > + struct platform_device *dwc3_pdev;
> > + struct device *dwc3_dev;
> > + struct device_node *dwc3_node;
> > + enum usb_dr_mode dr_mode;
> > + int ret = 0;
> > +
> > + ret = dwc3_rtk_init(rtk);
> > + if (ret)
> > + return -EINVAL;
> > +
> > + ret = of_platform_populate(node, NULL, NULL, dev);
> > + if (ret) {
> > + dev_err(dev, "failed to add dwc3 core\n");
> > + return ret;
> > + }
> > +
> > + dwc3_node = of_get_compatible_child(node, "snps,dwc3");
> > + if (!dwc3_node) {
> > + dev_err(dev, "failed to find dwc3 core node\n");
> > + ret = -ENODEV;
> > + goto depopulate;
> > + }
> > +
> > + dwc3_pdev = of_find_device_by_node(dwc3_node);
> > + if (!dwc3_pdev) {
> > + dev_err(dev, "failed to find dwc3 core platform_device\n");
> > + ret = -ENODEV;
> > + goto err_node_put;
> > + }
> > +
> > + dwc3_dev = &dwc3_pdev->dev;
> > + rtk->dwc = platform_get_drvdata(dwc3_pdev);
> > + if (!rtk->dwc) {
> > + dev_err(dev, "failed to find dwc3 core\n");
> > + ret = -ENODEV;
> > + goto err_pdev_put;
> > + }
> > +
> > + dr_mode = usb_get_dr_mode(dwc3_dev);
> > + if (dr_mode != rtk->dwc->dr_mode) {
> > + dev_info(dev, "dts set dr_mode=%d, but dwc3 set
> dr_mode=%d\n",
> > + dr_mode, rtk->dwc->dr_mode);
>
> This looks like it's dev_dbg?
This a special case. I prefer to keep it.
>
> > + dr_mode = rtk->dwc->dr_mode;
> > + }
> > +
> > + switch (dr_mode) {
> > + case USB_DR_MODE_PERIPHERAL:
> > + rtk->cur_role = USB_ROLE_DEVICE;
> > + break;
> > + case USB_DR_MODE_HOST:
> > + rtk->cur_role = USB_ROLE_HOST;
> > + break;
> > + default:
> > + dev_dbg(rtk->dev, "%s: dr_mode=%d\n", __func__,
> dr_mode);
> > + break;
> > + }
> > +
> > + if (device_property_read_bool(dwc3_dev, "usb-role-switch")) {
> > + ret = dwc3_rtk_setup_role_switch(rtk);
> > + if (ret) {
> > + dev_err(dev, "dwc3_rtk_setup_role_switch
> fail=%d\n", ret);
> > + goto err_pdev_put;
> > + }
> > + rtk->cur_role = dwc3_rtk_get_role(rtk);
> > + }
> > +
> > + switch_usb2_role(rtk, rtk->cur_role);
> > +
> > + return 0;
> > +
> > +err_pdev_put:
> > + platform_device_put(dwc3_pdev);
> > +err_node_put:
> > + of_node_put(dwc3_node);
> > +depopulate:
> > + of_platform_depopulate(dev);
> > +
> > + return ret;
> > +}
> > +
> > +static int dwc3_rtk_probe(struct platform_device *pdev) {
> > + struct dwc3_rtk *rtk;
> > + struct device *dev = &pdev->dev;
> > + struct resource *res;
> > + void __iomem *regs;
> > + int ret = 0;
> > +
> > + rtk = devm_kzalloc(dev, sizeof(*rtk), GFP_KERNEL);
> > + if (!rtk) {
> > + ret = -ENOMEM;
> > + goto out;
> > + }
> > +
> > + platform_set_drvdata(pdev, rtk);
> > +
> > + rtk->dev = dev;
> > +
> > + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> > + if (!res) {
> > + dev_err(dev, "missing memory resource\n");
> > + ret = -ENODEV;
> > + goto out;
> > + }
> > +
> > + regs = devm_ioremap_resource(dev, res);
> > + if (IS_ERR(regs)) {
> > + ret = PTR_ERR(regs);
> > + goto out;
> > + }
> > +
> > + rtk->regs = regs;
> > + rtk->regs_size = resource_size(res);
> > +
> > + res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
> > + if (res) {
> > + rtk->pm_base = devm_ioremap_resource(dev, res);
> > + if (IS_ERR(rtk->pm_base)) {
> > + ret = PTR_ERR(rtk->pm_base);
> > + goto out;
> > + }
> > + }
> > +
> > + ret = dwc3_rtk_probe_dwc3_core(rtk);
> > +
> > +out:
> > + return ret;
> > +}
> > +
> > +static void dwc3_rtk_remove(struct platform_device *pdev) {
> > + struct dwc3_rtk *rtk = platform_get_drvdata(pdev);
> > +
> > + rtk->dwc = NULL;
> > +
> > + dwc3_rtk_remove_role_switch(rtk);
> > +
> > + of_platform_depopulate(rtk->dev); }
> > +
> > +static void dwc3_rtk_shutdown(struct platform_device *pdev) {
> > + struct dwc3_rtk *rtk = platform_get_drvdata(pdev);
> > +
> > + of_platform_depopulate(rtk->dev); }
> > +
> > +static const struct of_device_id rtk_dwc3_match[] = {
> > + { .compatible = "realtek,rtd-dwc3" },
> > + {},
> > +};
> > +MODULE_DEVICE_TABLE(of, rtk_dwc3_match);
> > +
> > +#ifdef CONFIG_PM_SLEEP
> > +static int dwc3_rtk_suspend(struct device *dev) {
> > + return 0;
> > +}
> > +
> > +static int dwc3_rtk_resume(struct device *dev) {
> > + struct dwc3_rtk *rtk = dev_get_drvdata(dev);
> > +
> > + dwc3_rtk_init(rtk);
> > +
> > + switch_usb2_role(rtk, rtk->cur_role);
> > +
> > + /* runtime set active to reflect active state. */
> > + pm_runtime_disable(dev);
> > + pm_runtime_set_active(dev);
> > + pm_runtime_enable(dev);
> > +
> > + return 0;
> > +}
> > +
> > +static const struct dev_pm_ops dwc3_rtk_dev_pm_ops = {
> > + SET_SYSTEM_SLEEP_PM_OPS(dwc3_rtk_suspend,
> dwc3_rtk_resume) };
> > +
> > +#define DEV_PM_OPS (&dwc3_rtk_dev_pm_ops)
> > +#else
> > +#define DEV_PM_OPS NULL
> > +#endif /* CONFIG_PM_SLEEP */
> > +
> > +static struct platform_driver dwc3_rtk_driver = {
> > + .probe = dwc3_rtk_probe,
> > + .remove_new = dwc3_rtk_remove,
> > + .driver = {
> > + .name = "rtk-dwc3",
> > + .of_match_table = rtk_dwc3_match,
> > + .pm = DEV_PM_OPS,
> > + },
> > + .shutdown = dwc3_rtk_shutdown,
> > +};
> > +
> > +module_platform_driver(dwc3_rtk_driver);
> > +
> > +MODULE_AUTHOR("Stanley Chang <stanley_chang@xxxxxxxxxxx>");
> > +MODULE_DESCRIPTION("DesignWare USB3 Realtek Glue Layer");
> > +MODULE_ALIAS("platform:rtk-dwc3");
> > +MODULE_LICENSE("GPL");
> > +MODULE_SOFTDEP("pre: phy_rtk_usb2 phy_rtk_usb3");
> > --
> > 2.34.1
> >
>
> If you feel that we must keep the dev_info comments, it's fine with me.
>
> Just minor nits, I don't think those warrant a hold. Here's the Ack whether you
> made the change:
>
> Acked-by: Thinh Nguyen <Thinh.Nguyen@xxxxxxxxxxxx>
>
Thank you for your comment.
There are 3 dev_info here, only some special cases will be printed.
So I prefer to keep them.
I will submit a patch for minor change.
Thank,
Stanley
