From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932781AbcGLCX4 (ORCPT ); Mon, 11 Jul 2016 22:23:56 -0400 Received: from mga02.intel.com ([134.134.136.20]:38280 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751887AbcGLCXz (ORCPT ); Mon, 11 Jul 2016 22:23:55 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.28,349,1464678000"; d="scan'208";a="1019882707" Subject: Re: [PATCH] usb:solve resume usb device identification problem To: Lipengcheng , "gregkh@linuxfoundation.org" , "stern@rowland.harvard.edu" , "chasemetzger15@gmail.com" , "mathias.nyman@linux.intel.com" , "oneukum@suse.com" , "jun.li@freescale.com" References: <1468241823-116879-1-git-send-email-lpc.li@hisilicon.com> <57843CC3.7050204@linux.intel.com> <637796ED17F7774FB27D6AAE3C6951584A92BE8A@SZXEMA509-MBS.china.huawei.com> Cc: "linux-usb@vger.kernel.org" , "linux-kernel@vger.kernel.org" From: Lu Baolu Message-ID: <578454B8.3020608@linux.intel.com> Date: Tue, 12 Jul 2016 10:23:52 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.5.1 MIME-Version: 1.0 In-Reply-To: <637796ED17F7774FB27D6AAE3C6951584A92BE8A@SZXEMA509-MBS.china.huawei.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, On 07/12/2016 09:48 AM, Lipengcheng wrote: > Hi, > >> -----Original Message----- >> From: Lu Baolu [mailto:baolu.lu@linux.intel.com] >> Sent: Tuesday, July 12, 2016 8:42 AM >> To: Lipengcheng; gregkh@linuxfoundation.org; stern@rowland.harvard.edu; chasemetzger15@gmail.com; mathias.nyman@linux.intel.com; >> oneukum@suse.com; jun.li@freescale.com >> Cc: linux-usb@vger.kernel.org; linux-kernel@vger.kernel.org >> Subject: Re: [PATCH] usb:solve resume usb device identification problem >> >> Hi, >> >> On 07/11/2016 08:57 PM, Pengcheng Li wrote: >>> A usb device in the connection state. Then host is suspend and resume. >>> But the usb device could not be at the right speed. We should be reset >>> the reset. >> Have you tried applying XHCI_RESET_ON_RESUME quirk to your host controller driver? Is your usb device self powered? >> > I do not apply XHCI_RESET_ON_RESUME quir to my host controller driver. I select no pci platform. Our usb device is not self powered. This quirk is not pci specific. >> Best regards, >> Lu Baolu >> >>> Signed-off-by: Pengcheng Li >>> --- >>> drivers/usb/core/hub.c | 6 +++++- >>> 1 file changed, 5 insertions(+), 1 deletion(-) >>> >>> diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c index >>> bee1351..cd71bb3 100644 >>> --- a/drivers/usb/core/hub.c >>> +++ b/drivers/usb/core/hub.c >>> @@ -3455,7 +3455,7 @@ int usb_port_resume(struct usb_device *udev, pm_message_t msg) >>> struct usb_hub *hub = usb_hub_to_struct_hub(udev->parent); >>> struct usb_port *port_dev = hub->ports[udev->portnum - 1]; >>> int port1 = udev->portnum; >>> - int status; >>> + int status, retval; >>> u16 portchange, portstatus; >>> >>> if (!test_and_set_bit(port1, hub->child_usage_bits)) { @@ -3512,6 >>> +3512,10 @@ int usb_port_resume(struct usb_device *udev, pm_message_t msg) >>> } >>> } >>> >>> + retval = hub_port_reset(hub, port1, udev, HUB_ROOT_RESET_TIME, false); >>> + if (retval < 0) >>> + hub_port_disable(hub, port1, 0); >>> + If I understand it right, this is a "host + device" specific issue. This line of code might solve your issue, but it impacts all other hosts and devices which don't have such problem. Best regards, Lu Baolu