Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751337AbdHRIGd (ORCPT ); Fri, 18 Aug 2017 04:06:33 -0400 Received: from mail-oi0-f45.google.com ([209.85.218.45]:36204 "EHLO mail-oi0-f45.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750739AbdHRIG3 (ORCPT ); Fri, 18 Aug 2017 04:06:29 -0400 MIME-Version: 1.0 In-Reply-To: <87lgmhqr0e.fsf@linux.intel.com> References: <20170818042050.1728-1-kai.heng.feng@canonical.com> <87lgmhqr0e.fsf@linux.intel.com> From: Kai-Heng Feng Date: Fri, 18 Aug 2017 16:06:28 +0800 Message-ID: Subject: Re: [PATCH] usb: xhci: Renesas uPD720202 needs short TX quirk To: Felipe Balbi Cc: mathias.nyman@intel.com, gregkh@linuxfoundation.org, USB list , LKML Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2087 Lines: 63 Hi, On Fri, Aug 18, 2017 at 3:22 PM, Felipe Balbi wrote: > > hi, > > Kai-Heng Feng writes: >> When plugging Logitech C920 webcam, warning messages filled up dmesg: >> [77117.655018] xhci_hcd 0000:0c:00.0: WARN Successful completion on short TX: needs XHCI_TRUST_TX_LENGTH quirk? >> [77117.659018] xhci_hcd 0000:0c:00.0: WARN Successful completion on short TX: needs XHCI_TRUST_TX_LENGTH quirk? > > have you confirmed this is needed for this controller? I just found commit d2f48f05cd2a2 ("usb: xhci: ASMedia ASM1042A chipset need shorts TX quirk") and did the same thing for this controller. > Anybody from Renesas has confirmed it? No, it's a user reported problem, please check the bug report in the link. > Do you have an errata document to refer to? No. Probably need Renesas guy to provide it. > >> [77122.622952] handle_tx_event: 541 callbacks suppressed >> >> No more warning messages with XHCI_TRUST_TX_LENGTH applied. >> >> BugLink: https://bugs.launchpad.net/bugs/1710548 >> Signed-off-by: Kai-Heng Feng >> --- >> drivers/usb/host/xhci-pci.c | 4 +++- >> 1 file changed, 3 insertions(+), 1 deletion(-) >> >> diff --git a/drivers/usb/host/xhci-pci.c b/drivers/usb/host/xhci-pci.c >> index 8071c8fdd15e..8566b43e19ba 100644 >> --- a/drivers/usb/host/xhci-pci.c >> +++ b/drivers/usb/host/xhci-pci.c >> @@ -202,8 +202,10 @@ static void xhci_pci_quirks(struct device *dev, struct xhci_hcd *xhci) >> xhci->quirks |= XHCI_BROKEN_STREAMS; >> } >> if (pdev->vendor == PCI_VENDOR_ID_RENESAS && >> - pdev->device == 0x0015) >> + pdev->device == 0x0015) { > > unnecessary > >> xhci->quirks |= XHCI_RESET_ON_RESUME; >> + xhci->quirks |= XHCI_TRUST_TX_LENGTH; > > xhci->quirks |= XHCI_RESET_ON_RESUME | > XHCI_TRUST_TX_LENGTH; > >> + } > > unnecessary Do you mean that this quirk just hide the warning, it doesn't fix the root cause? > > -- > balbi