Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752345AbdFOOMS (ORCPT ); Thu, 15 Jun 2017 10:12:18 -0400 Received: from iolanthe.rowland.org ([192.131.102.54]:46150 "HELO iolanthe.rowland.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1751677AbdFOOMR (ORCPT ); Thu, 15 Jun 2017 10:12:17 -0400 Date: Thu, 15 Jun 2017 10:12:15 -0400 (EDT) From: Alan Stern X-X-Sender: stern@iolanthe.rowland.org To: Kai-Heng Feng cc: Bjorn Helgaas , Bjorn Helgaas , , USB list , , LKML , "Rafael J. Wysocki" , Subject: Re: [PATCH] usb: host: ehci: workaround PME bug on AMD EHCI controller In-Reply-To: Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1240 Lines: 29 On Thu, 15 Jun 2017, Kai-Heng Feng wrote: > On Wed, Jun 14, 2017 at 1:28 AM, Bjorn Helgaas wrote: > > > > The lspci output [1] shows: > > > > 00:12.0 USB controller: Advanced Micro Devices, Inc. [AMD] FCH USB EHCI Controller (rev 39) (prog-if 20 [EHCI]) > > Capabilities: [c0] Power Management version 2 > > Flags: PMEClk- DSI- D1+ D2+ AuxCurrent=0mA PME(D0+,D1+,D2+,D3hot+,D3cold+) > > Status: D3 NoSoftRst- PME-Enable+ DSel=0 DScale=0 PME- > > Bridge: PM- B3+ > > > > The device claims it can assert PME# from D3hot. If it can't, that > > sounds like a hardware defect that should be addressed with a quirk. > > Ideally we would also have a pointer to the AMD hardware erratum. > > Looks like it's pretty similar to "23 USB Wake on Connect/Disconnect > with Low Speed Devices" in [1]. > It points to a workaround in appendix A2 from [2]. > However it says this bug only effects Low Speed devices, but it > actually also happens on High Speed devices. > > [1] https://support.amd.com/TechDocs/46837.pdf > [2] https://support.amd.com/TechDocs/42413.pdf Those documents refer to a hardware bug with a workaround in the BIOS. Have you checked to see if your BIOS is up to date? Alan Stern