[PATCH v1 2/4] arm64: dts: imx8mq-nitrogen: add USB HOST support

Ahmad Fatoum a.fatoum at pengutronix.de
Tue Mar 30 09:38:20 BST 2021


Hello Adrien,

On 30.03.21 10:35, Adrien Grassein wrote:
> Add the description for the USB host port.
> At this time, the port will not work directly from the
> kernel because it's connected through a resettable hub
> that is not handle in the kernel. It should be controlled
> in the bootloader or in the userspace.

Couldn't you add a gpio-hog that gets the hub out of reset?

Cheers,
Ahmad

> 
> In the case of the Boundary's u-boot, this is done on the
> boot script:
> "
> starting USB...
> Bus usb at 38100000: Register 2000140 NbrPorts 2
> Starting the controller
> USB XHCI 1.10
> Bus usb at 38200000: Register 2000140 NbrPorts 2
> Starting the controller
> USB XHCI 1.10
> scanning bus usb at 38100000 for devices... 1 USB Device(s) found
> scanning bus usb at 38200000 for devices... 3 USB Device(s) found
> "
> 
> Signed-off-by: Adrien Grassein <adrien.grassein at gmail.com>
> ---
>  .../boot/dts/freescale/imx8mq-nitrogen.dts    | 22 +++++++++++++++++++
>  1 file changed, 22 insertions(+)
> 
> diff --git a/arch/arm64/boot/dts/freescale/imx8mq-nitrogen.dts b/arch/arm64/boot/dts/freescale/imx8mq-nitrogen.dts
> index b46f45a82be1..7a52e247c527 100644
> --- a/arch/arm64/boot/dts/freescale/imx8mq-nitrogen.dts
> +++ b/arch/arm64/boot/dts/freescale/imx8mq-nitrogen.dts
> @@ -213,6 +213,22 @@ &usb3_phy0 {
>  	status = "okay";
>  };
>  
> +&usb_dwc3_1 {
> +	dr_mode = "host";
> +	status = "okay";
> +};
> +
> +/*
> + * On this board, USB host is connected to a resettable hub.
> + * The reset signal is connected to the GPIO <&gpio1 14 GPIO_ACTIVE_LOW>.
> + * You need to activate it in the bootloader or in the userspace.
> + */
> +&usb3_phy1 {
> +	status = "okay";
> +	pinctrl-names = "default";
> +	pinctrl-0 = <&pinctrl_usb3_1>;
> +};
> +
>  &usdhc1 {
>  	assigned-clocks = <&clk IMX8MQ_CLK_USDHC1>;
>  	assigned-clock-rates = <400000000>;
> @@ -388,6 +404,12 @@ MX8MQ_IOMUXC_GPIO1_IO13_USB1_OTG_OC		0x16
>  		>;
>  	};
>  
> +	pinctrl_usb3_1: usb3-1grp {
> +		fsl,pins = <
> +			MX8MQ_IOMUXC_GPIO1_IO14_GPIO1_IO14		0x16
> +		>;
> +	};
> +
>  	pinctrl_usdhc1: usdhc1grp {
>  		fsl,pins = <
>  			MX8MQ_IOMUXC_SD1_CLK_USDHC1_CLK			0x83
> 

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