Re: [PATCH v3 2/2] dt-bindings: usb: snps,dwc3: Add 'snps,parkmode-disable-hs-quirk' quirk

[Rob Herring <robh@kernel.org>]

On Thu, 13 Apr 2023 18:09:14 +0800, Stanley Chang wrote:
> Add a new 'snps,parkmode-disable-hs-quirk' DT quirk to dwc3 core for
> disable the high-speed parkmode.
> 
> For some USB wifi devices, if enable this feature it will reduce the
> performance. Therefore, add an option for disabling HS park mode by
> device-tree.
> 
> In Synopsys's dwc3 data book:
> In a few high speed devices when an IN request is sent within 900ns of the
> ACK of the previous packet, these devices send a NAK. When connected to
> these devices, if required, the software can disable the park mode if you
> see performance drop in your system. When park mode is disabled,
> pipelining of multiple packet is disabled and instead one packet at a time
> is requested by the scheduler. This allows up to 12 NAKs in a micro-frame
> and improves performance of these slow devices.
> 
> Signed-off-by: Stanley Chang <stanley_chang@realtek.com>
> ---
> v2 to v3 change:
> 1. Add the comment message.
> 2. cc the right maintainers.
> ---
>  Documentation/devicetree/bindings/usb/snps,dwc3.yaml | 5 +++++
>  1 file changed, 5 insertions(+)
> 

Acked-by: Rob Herring <robh@kernel.org>