RE: [PATCH] usb: dwc3: core: Add quirk for enabling AutoRetry feature in the controller

[Anurag Kumar Vulisha]

Hi Felipe,

>-----Original Message-----
>From: Felipe Balbi [mailto:balbi@xxxxxxxxxx]
>Sent: Thursday, July 26, 2018 4:44 PM
>To: Anurag Kumar Vulisha <anuragku@xxxxxxxxxx>; Rob Herring <robh@xxxxxxxxxx>
>Cc: gregkh@xxxxxxxxxxxxxxxxxxx; mark.rutland@xxxxxxx;
>v.anuragkumar@xxxxxxxxx; linux-usb@xxxxxxxxxxxxxxx; devicetree@xxxxxxxxxxxxxxx;
>linux-kernel@xxxxxxxxxxxxxxx
>Subject: RE: [PATCH] usb: dwc3: core: Add quirk for enabling AutoRetry feature in the
>controller
>
>
>>>>
>>>> diff --git a/Documentation/devicetree/bindings/usb/dwc3.txt
>>>b/Documentation/devicetree/bindings/usb/dwc3.txt
>>>> index 7f13ebe..2ba2bc2 100644
>>>> --- a/Documentation/devicetree/bindings/usb/dwc3.txt
>>>> +++ b/Documentation/devicetree/bindings/usb/dwc3.txt
>>>> @@ -94,6 +94,11 @@ 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,enable_auto_retry: Set to enable Auto retry Feature to make
>>>> + the
>>>
>>>s/_/-/
>> Sorry, I am not able to understand what needs to fixed here. Please
>> help me in understanding, so that I can fix it in v2.
>
>replace _ with -
>
>>>> +			controller operating in Host mode on seeing transaction
>>>> +			errors(CRC errors or internal overrun scenerios) on IN
>>>> +			transfers to reply to the device with a non-terminating
>>>> +			retry ACK (i.e, an ACK TP with Retry=1 & Nump != 0)
>>>
>>>Seems like the property is unnecessary. When would you not want this
>>>retry behavior? Why not just enable unconditionally in the driver?
>>>
>> There is no harm in adding this fix always but I think this Retry
>> feature should be added depending on the user and type of the
>> application. For example, applying this feature in a streaming
>> application where isochronous transfers are used might end up in
>
>read the docs. Auto Retry in only for non-isochronous IN endpoints. You don't need
>any quirk for this. Just enable it unconditionally. Actually, you wanna make sure the
>core can run in Host mode before setting this, but that's it. No need for a quirk.
>
Thanks for making me understand. Will remove this quirk and send v2

Best Regards,
Anurag Kumar Vulisha