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

[Roger Quadros]

Hi Andrejs,

On 09/02/2024 15:02, Andrejs Cainikovs wrote:
> From: Andrejs Cainikovs <andrejs.cainikovs at toradex.com>
> 
> 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 at toradex.com>
> ---
>  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 at 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 at 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@kernel.org/

-- 
cheers,
-roger