Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752655AbbKQD4R (ORCPT ); Mon, 16 Nov 2015 22:56:17 -0500 Received: from mail-yk0-f172.google.com ([209.85.160.172]:34975 "EHLO mail-yk0-f172.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752147AbbKQD4P (ORCPT ); Mon, 16 Nov 2015 22:56:15 -0500 MIME-Version: 1.0 In-Reply-To: <2B3535C5ECE8B5419E3ECBE30077290901DC3C8CA4@US01WEMBX2.internal.synopsys.com> References: <1446802612-5828-1-git-send-email-lyz@rock-chips.com> <563C7B48.2020308@rock-chips.com> <2B3535C5ECE8B5419E3ECBE30077290901DC3C8CA4@US01WEMBX2.internal.synopsys.com> Date: Mon, 16 Nov 2015 19:56:14 -0800 X-Google-Sender-Auth: ZYHZgVqySl1Y0zYhGGwmoawuXbQ Message-ID: Subject: Re: [RFC] usb: dwc2: hcd: fix split schedule issue From: Doug Anderson To: John Youn Cc: Yunzhi Li , Julius Werner , Dinh Nguyen , "Kaukab, Yousaf" , "linux-usb@vger.kernel.org" , "linux-kernel@vger.kernel.org" , wulf , Kever Yang , caesar , Tao Huang , rockchip-discuss 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: 2362 Lines: 63 John, On Wed, Nov 11, 2015 at 8:29 PM, John Youn wrote: > On 11/11/2015 4:22 PM, Doug Anderson wrote: >> John, >> >> On Fri, Nov 6, 2015 at 2:04 AM, Yunzhi Li wrote: >>> hi John , >>> >>> As we talked yesterday, I tried to fix the split schedule sequence. This >>> patch will >>> avoid scheduling SSPLIT-IN packet for another device between >>> SSPLIT-OUT-begin and >>> SSPLIT-OUT-end, now the keyboard and Jebra audio speaker could work together >>> well, but >>> I'm not sure if this is exactly the right way to schedule split transfers >>> and if there >>> is any dide effect with this patch. Please help review this patch. Thanks. >>> >>>> Fix dwc2 split schedule sequence issue. Not schedule a SSPLIT_IN >>>> packet between SSPLIT-begin and SSPLIT-end. >>>> >>>> Signed-off-by: Yunzhi Li >>>> --- >>>> drivers/usb/dwc2/hcd.c | 4 ++++ >>>> 1 file changed, 4 insertions(+) >> >> Did you have any thoughts on this patch? Although this patch didn't >> fix the problems I was seeing with the Microsoft Wireless Keyboard >> (see the patch I sent out earlier which does seem to fix it), I can >> confirm that in a different setup (HUB goes to USB audio + mouse) that >> this patch does fix some problems. >> >> That being said, it feels to me like a band-aid rather than an actual >> fix (I'm talking out of my rear end, though, since my USB experience >> is lacking at best). It feels like perhaps we're just not keeping >> track the xact_pos correctly, but of course I don't know that for >> sure... >> >> Anyway, just fishing... ;) >> >> -Doug >> > > Hi Doug, > > I also feel it is not quite right as the SSPLIT should be able to > happen during the SSPLIT of another device. I tried to reproduce > and see the same scheduling but don't see any hang due to it. > > Yunzhi, any details on what kind of hub and keyboard you are > using? I have the same Jabra 410 speaker. Just to tie things together for anyone following along, my current thoughts on how to fix this are something like . -Doug -- 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/