Re: [PATCH] usb: xhci: Add XHCI_TRUST_TX_LENGTH for Renesas uPD720201

[Ard Biesheuvel]

On 12 December 2017 at 16:47, Daniel Thompson
<daniel.thompson@xxxxxxxxxx> wrote:
> When plugging in a USB webcam I see the following message:
> xhci_hcd 0000:04:00.0: WARN Successful completion on short TX: needs
> XHCI_TRUST_TX_LENGTH quirk?
> handle_tx_event: 913 callbacks suppressed
>
> All is quiet again with this patch (and I've done a fair but of soak
> testing with the camera since).
>
> Cc: <stable@xxxxxxxxxxxxxxx>
> Signed-off-by: Daniel Thompson <daniel.thompson@xxxxxxxxxx>

I have been setting this quirk manually for ages on my kernel command
line, for the same reason (MS HD Webcam), and with the same positive
result, so

Acked-by: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx>

> ---
>  drivers/usb/host/xhci-pci.c | 3 +++
>  1 file changed, 3 insertions(+)
>
> diff --git a/drivers/usb/host/xhci-pci.c b/drivers/usb/host/xhci-pci.c
> index 7ef1274ef7f7..1aad89b8aba0 100644
> --- a/drivers/usb/host/xhci-pci.c
> +++ b/drivers/usb/host/xhci-pci.c
> @@ -177,6 +177,9 @@ static void xhci_pci_quirks(struct device *dev, struct xhci_hcd *xhci)
>                 xhci->quirks |= XHCI_TRUST_TX_LENGTH;
>                 xhci->quirks |= XHCI_BROKEN_STREAMS;
>         }
> +       if (pdev->vendor == PCI_VENDOR_ID_RENESAS &&
> +                       pdev->device == 0x0014)
> +               xhci->quirks |= XHCI_TRUST_TX_LENGTH;
>         if (pdev->vendor == PCI_VENDOR_ID_RENESAS &&
>                         pdev->device == 0x0015)
>                 xhci->quirks |= XHCI_RESET_ON_RESUME;
> --
> 2.14.2
>