Re: [PATCH v1] arm64: dts: ti: k3-am62-main: disable usb lpm

From: Roger Quadros
Date: Mon Feb 12 2024 - 07:15:54 EST


Hi Andrejs,

On 09/02/2024 15:02, Andrejs Cainikovs wrote:
> From: Andrejs Cainikovs <andrejs.cainikovs@xxxxxxxxxxx>
>
> AM62 USB works with some devices, while failing to operate with others.

Could you please share which devices failed to work for you?

>
> [ 560.189822] xhci-hcd xhci-hcd.4.auto: xHCI Host Controller
> [ 560.195631] xhci-hcd xhci-hcd.4.auto: new USB bus registered, assigned bus number 2
> [ 574.388509] xhci-hcd xhci-hcd.4.auto: can't setup: -110
> [ 574.393814] xhci-hcd xhci-hcd.4.auto: USB bus 2 deregistered
> [ 574.399544] xhci-hcd: probe of xhci-hcd.4.auto failed with error -110
>
> This seems to be related to LPM (Link Power Management), and disabling it
> turns USB into reliable working state.
>
> As per AM62 reference manual:
>
>> 4.8.2.1 USB2SS Unsupported Features
>>
>> The following features are not supported on this family of devices:
>> ...
>> - USB 2.0 ECN: Link Power Management (LPM)
>> ...
>
> Fixes: 2240f96cf3cd ("arm64: dts: ti: k3-am62-main: Add support for USB")
> Signed-off-by: Andrejs Cainikovs <andrejs.cainikovs@xxxxxxxxxxx>
> ---
> arch/arm64/boot/dts/ti/k3-am62-main.dtsi | 4 ++++
> 1 file changed, 4 insertions(+)
>
> diff --git a/arch/arm64/boot/dts/ti/k3-am62-main.dtsi b/arch/arm64/boot/dts/ti/k3-am62-main.dtsi
> index 464b7565d085..c49fbce5cb70 100644
> --- a/arch/arm64/boot/dts/ti/k3-am62-main.dtsi
> +++ b/arch/arm64/boot/dts/ti/k3-am62-main.dtsi
> @@ -640,6 +640,8 @@ usb0: usb@31000000 {
> interrupt-names = "host", "peripheral";
> maximum-speed = "high-speed";
> dr_mode = "otg";
> + snps,usb2-gadget-lpm-disable;
> + snps,usb2-lpm-disable;
> };
> };
>
> @@ -663,6 +665,8 @@ usb1: usb@31100000 {
> interrupt-names = "host", "peripheral";
> maximum-speed = "high-speed";
> dr_mode = "otg";
> + snps,usb2-gadget-lpm-disable;
> + snps,usb2-lpm-disable;
> };
> };
>

Instead of this could you please check if this series fixes the issue for you?
https://lore.kernel.org/all/20240205141221.56076-1-rogerq@xxxxxxxxxx/

--
cheers,
-roger