RK3399 USB Driver

USB 概念

USB(Universal Serial Bus) 通用串行总线，目标是实现即插即用

USB 和其他接口的区别如下图

usb_vs_others

USB Host Controller Interface

usb_host_controller_interface

USB Connector Type

usb_connector

RK USB 控制器

Rockchip SOC 通常内置多个 USB 控制器,不同控制器互相独立。

RK3399 2 个 USB 2.0 HOST(EHCI/OHCI)， 1 个 USB HSIC(EHCI)，2 个 USB 3.0/2.0 OTG(DWC3/xHCI)

HSIC—USB High Speed Inter-Chip 是一个两线源同步的串行接口，使用240MHz双倍数据速率产生480MHz的高速速率，和传统的USB电缆连接拓扑结构的主机完全兼容, 常用在3G 和 4G模块中。

rk3399_usb

USB 2.0 HOST

usb2_host

USB 2.0 Host 硬件电路有两种:USB 2.0 Host 和 USB 2.0 HSIC。虽然 USB 2.0 Host 和 HSIC 都使用 EHCI 控制器,但使用的 USB 2.0 PHY 不同,所以对应的硬件电路也不同。

硬件电路

usb_hub

FE1.1S是用于USB2.0 HUB的主控IC, 提供4个USB Port

USB 2.0 OTG

usb2_otg

USB 3.0 OTG

usb3_otg

USB 2.0 PHY

USB 2.0 PHY 支持 1 个 port 和 2 个 port 两种设计,如下图 1-4 是支持 2 个 port 的框图。

usb2_phy

Host Port:通过 UTMI+ 连接到 USB 2.0 Host 控制器;
OTG Port:通过 UTMI+ 连接 USB 3.0 或者 USB 2.0 OTG 控制器的 USB 2.0 逻辑模块;

USB 3.0 Type-C PHY

usb_typec

内核配置

kernel/arch/arm64/configs/rockchip_defconfig

# USB PHY CONFIG
CONFIG_PHY_ROCKCHIP_USB=y
CONFIG_PHY_ROCKCHIP_INNO_USB2=y
CONFIG_PHY_ROCKCHIP_INNO_USB3=y
CONFIG_PHY_ROCKCHIP_TYPEC=y

# USB Host CONFIG
CONFIG_USB_XHCI_HCD=y
CONFIG_USB_EHCI_HCD=y
CONFIG_USB_EHCI_HCD_PLATFORM=y
CONFIG_USB_OHCI_HCD=y
CONFIG_USB_OHCI_HCD_PLATFORM=y

# USB OTG CONFIG
CONFIG_USB_DWC3=y
CONFIG_USB_DWC2=y

# USB Gadget
CONFIG_USB_GADGET=y
CONFIG_USB_GADGET_DEBUG_FILES=y
CONFIG_USB_GADGET_VBUS_DRAW=500
CONFIG_USB_CONFIGFS=y
CONFIG_USB_CONFIGFS_ACM=y
CONFIG_USB_CONFIGFS_RNDIS=y
CONFIG_USB_CONFIGFS_MASS_STORAGE=y
CONFIG_USB_CONFIGFS_F_FS=y
CONFIG_USB_CONFIGFS_F_MTP=y
CONFIG_USB_CONFIGFS_F_PTP=y
CONFIG_USB_CONFIGFS_F_ACC=y
CONFIG_USB_CONFIGFS_F_AUDIO_SRC=y
CONFIG_USB_CONFIGFS_UEVENT=y
CONFIG_USB_CONFIGFS_F_MIDI=y

# Others

USB DTS 配置说明

USB PHY 分为 USB 2.0 PHY 和 USB 3.0 PHY 两种。这两种 PHY 是互相独立的,并且特性差异比较大,所以需要分别配置 DTS。

Note:RK3399 芯片的 USB PHY DTS 配置比较灵活且复杂,请参考文档:《Rockchip_RK3399_Developer_Guide_USB_DTS_CN》

rk3399_usb_control

USB 2.0 PHY DTS

arch/arm64/boot/dts/rockchip/rk3399.dtsi

        grf: syscon@ff770000 {
                compatible = "rockchip,rk3399-grf", "syscon", "simple-mfd";
                reg = <0x0 0xff770000 0x0 0x10000>;
                #address-cells = <1>;
                #size-cells = <1>;

                u2phy0: usb2-phy@e450 {
                        compatible = "rockchip,rk3399-usb2phy";
                        reg = <0xe450 0x10>;
                        clocks = <&cru SCLK_USB2PHY0_REF>;
                        clock-names = "phyclk";
                        #clock-cells = <0>;
                        clock-output-names = "clk_usbphy0_480m";
                        power-domains = <&power RK3399_PD_PERIHP>;
                        status = "disabled";

                        u2phy0_otg: otg-port {
                                #phy-cells = <0>;
                                interrupts = <GIC_SPI 103 IRQ_TYPE_LEVEL_HIGH 0>,
                                             <GIC_SPI 104 IRQ_TYPE_LEVEL_HIGH 0>,
                                             <GIC_SPI 106 IRQ_TYPE_LEVEL_HIGH 0>;
                                interrupt-names = "otg-bvalid", "otg-id",
                                                  "linestate";
                                status = "disabled";
                        };

                        u2phy0_host: host-port {
                                #phy-cells = <0>;
                                interrupts = <GIC_SPI 27 IRQ_TYPE_LEVEL_HIGH 0>;
                                interrupt-names = "linestate";
                                status = "disabled";
                        };
                };

        }

对于 Host port 和 OTG port Host 模式,需要为 USB 外设提供 5V 供电电源,所以我们要在 DTS 中配置 USB VBUS 5V

RK3399 USB 2.0 Host VBUS 的控制方式是: GPIO 拉高,则使能 VBUS 5V 输出,GPIO 拉低,则关闭 VBUS 5V 输出。DTS 中使用 regulator 的方式,来配置 GPIO。其中,属性 “regulator-always-on” 表示,系统启动后,就拉高 GPIO 以使能 VBUS 5V 输出,直到系统关机。

arch/arm64/boot/dts/rockchip/rk3399-evb.dtsi

        vcc5v0_host: vcc5v0-host-regulator {
                compatible = "regulator-fixed";
                enable-active-high;
                gpio = <&gpio4 25 GPIO_ACTIVE_HIGH>;
                pinctrl-names = "default";
                pinctrl-0 = <&host_vbus_drv>;
                regulator-name = "vcc5v0_host";
                regulator-always-on;
        };

        usb2 {
                host_vbus_drv: host-vbus-drv {
                        rockchip,pins =
                                <4 25 RK_FUNC_GPIO &pcfg_pull_none>;
                };
        };


&u2phy0 {
        status = "okay";
        //extcon = <&fusb0>;

        vbus-5v-gpios = <&gpio1 3 GPIO_ACTIVE_HIGH>; /* Vbus GPIO 配置 */
        u2phy0_otg: otg-port {
                status = "okay";
        };

        u2phy0_host: host-port {
                phy-supply = <&vcc5v0_host>;
                status = "okay";
        };
};

&u2phy1 {
        status = "okay";
        //extcon = <&fusb1>;

        u2phy1_otg: otg-port {
                status = "okay";
        };

        u2phy1_host: host-port {
                phy-supply = <&vcc5v0_host>;
                status = "okay";
        };
};

USB 3.0 PHY DTS