Re: [RFC PATCH 1/3] dt-bindings: usb: Add undetected disconnection quirk

[Rob Herring <robh@kernel.org>]

On Wed, Oct 21, 2020 at 10:15:43PM -0700, Thinh Nguyen wrote:
> Synopsys DWC_usb3x host controllers will not detect enhanced super-speed
> (eSS) device disconnection if it has active isochronous IN endpoint(s)

Why do you need a DT quirk if it's all DWC3? Imply it from the 
compatible.

> behind one or more eSS hubs. Introduce a quirk to workaround this for
> xhci and dwc3 device tree.
> 
> Signed-off-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
> ---
>  Documentation/devicetree/bindings/usb/dwc3.txt     | 3 +++
>  Documentation/devicetree/bindings/usb/usb-xhci.txt | 2 ++

These are getting converted to schema.

>  2 files changed, 5 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/usb/dwc3.txt b/Documentation/devicetree/bindings/usb/dwc3.txt
> index 1aae2b6160c1..b23b52f5842a 100644
> --- a/Documentation/devicetree/bindings/usb/dwc3.txt
> +++ b/Documentation/devicetree/bindings/usb/dwc3.txt
> @@ -105,6 +105,9 @@ Optional properties:
>  			this and tx-thr-num-pkt-prd to a valid, non-zero value
>  			1-16 (DWC_usb31 programming guide section 1.2.3) to
>  			enable periodic ESS TX threshold.
> + - snps,blocked-disconnection: enable workaround to undetected disconnection
> +			while isoc endpoint(s) are active for DWC_usb3x
> +			controllers operating as host

We certainly don't need 2 versions of the same property.

>   - <DEPRECATED> tx-fifo-resize: determines if the FIFO *has* to be reallocated.
>   - snps,incr-burst-type-adjustment: Value for INCR burst type of GSBUSCFG0
> diff --git a/Documentation/devicetree/bindings/usb/usb-xhci.txt b/Documentation/devicetree/bindings/usb/usb-xhci.txt
> index 0c5cff84a969..60812ae74d46 100644
> --- a/Documentation/devicetree/bindings/usb/usb-xhci.txt
> +++ b/Documentation/devicetree/bindings/usb/usb-xhci.txt
> @@ -28,6 +28,8 @@ Optional properties:
>    - quirk-broken-port-ped: set if the controller has broken port disable mechanism
>    - imod-interval-ns: default interrupt moderation interval is 5000ns
>    - phys : see usb-hcd.yaml in the current directory
> +  - blocked-disconnection: workaround undetected disconnection while isoc
> +		endpoint(s) are active
>  
>  additionally the properties from usb-hcd.yaml (in the current directory) are
>  supported.
> 
> base-commit: 270315b8235e3d10c2e360cff56c2f9e0915a252
> -- 
> 2.28.0
>