Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754556AbaGKXci (ORCPT ); Fri, 11 Jul 2014 19:32:38 -0400 Received: from mail-lb0-f169.google.com ([209.85.217.169]:61074 "EHLO mail-lb0-f169.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754212AbaGKXcg (ORCPT ); Fri, 11 Jul 2014 19:32:36 -0400 MIME-Version: 1.0 In-Reply-To: <1405059756-11983-1-git-send-email-gavin.guo@canonical.com> References: <1405059756-11983-1-git-send-email-gavin.guo@canonical.com> Date: Sat, 12 Jul 2014 07:32:34 +0800 Message-ID: Subject: Re: [PATCH 0/1] Fixes to the USB 3.0 detection as 2.0 on AMD platform From: Gavin Guo To: Sarah Sharp , "Nyman, Mathias" , linux-usb@vger.kernel.org, linux-kernel , gregkh@linuxfoundation.org Cc: YK , Anthony Wong , Gerald Yang Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi all, On Fri, Jul 11, 2014 at 2:22 PM, Gavin Guo wrote: > Hi Sarah and Mathias, > > As the discussion in http://comments.gmane.org/gmane.linux.usb.general/107011, > I found that [AMD] FCH USB XHCI Controller [1022:7814] the USB 3.0 disk > can't work in SuperSpeed after several times of hotplug. After doing some > experiments and bisection, I found the bug is caused by > 41e7e056cdc662f704fa9262e5c6e213b4ab45dd (USB: Allow USB 3.0 ports to be > disabled.). And the bug can be fixed by not executing the > hub_usb3_port_disable() function. I also found that the port status is > already in RxDetect before setting the port to Disabled in > hub_usb3_port_disable() function. So, there are 2 ways to fix the bug: > > 1) Check if the Vendor/Device id is [1022:7814] at the beginning of > hub_usb3_port_disable() function. If yes, return without executing the > remaining code. > > 2) Check if the port status is already in RxDetect, if yes, return without > executing the remaining code. > > The second method seems more reasonable, so the patch is the implementation > of the second one. But it will affect more platforms and I don't know if > there'll be any negative result. Otherwise, if the first one is correct, > I can reimplement a new one. > > I'm appreciated if you can give me some advice, or if there is any thing I missed. > > Thanks, > Gavin > > Gavin Guo (1): > usb: Check if port status is equal to RxDetect > > drivers/usb/core/hub.c | 19 +++++++++++++++++++ > 1 file changed, 19 insertions(+) > > -- > 2.0.0 > Add Greg k-h to the list. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/