RE: [PATCH] usb: gadget: f_fs: report error if excess data received

[Du, Changbin]

Hi,
> > I'd prefer fail the request at all, and it is better done in HW.
> > Because per the USB Spec that device can return NAK if a function was
> > unable to accept data From the host.  The DWC3 has not been design as
> > this, if software fail the transfer, it is a little weird for host.
> >
> > So, now we have 3 choices:
> > 1) buffer the excess data
> > 2) fail the transfer
> 
> You mean fail when more data has been sent (i.e. drop the whole packet)
> or fail at entry to read() if the buffer is not aligned?
> 
I mean the first one.

> > 3) drop the excess data, then print an warning message
> >
> > Which one do you prefer?
> 
> I think f_fs should mimic whatever happens if unaligned request is
> queued on dwc3.  As far as I understand, this is not 1.
> 
> Iâll be travelling again on Friday so Iâll finish up the patch doing 1
> so we will have a choice between 1 (my patch) and 3 (your patch).
> 
Great! Prefer your patch if #1 works good.

> --
> Best regards
> ããã âðððð86â ãããããã
> ÂIf at first you donât succeed, give up skydivingÂ

Best Regards,
Du, Changbin