Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751168AbcCFBib (ORCPT ); Sat, 5 Mar 2016 20:38:31 -0500 Received: from mail-vk0-f43.google.com ([209.85.213.43]:35468 "EHLO mail-vk0-f43.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751001AbcCFBia convert rfc822-to-8bit (ORCPT ); Sat, 5 Mar 2016 20:38:30 -0500 MIME-Version: 1.0 In-Reply-To: References: <1457115786-11370-1-git-send-email-dianders@chromium.org> <58FE77DF-E10D-4E16-8FC7-2D13C8037EFB@mniewoehner.de> <70F71E2A-40AD-4647-850E-5130DF9FB4D4@mniewoehner.de> Date: Sat, 5 Mar 2016 17:38:29 -0800 X-Google-Sender-Auth: qKmIajzOIBUztp-0R_pNNgOFHPc Message-ID: Subject: Re: [RFT PATCH 1/2] usb: dwc2: Add a 10 ms delay to dwc2_core_reset() From: Doug Anderson To: Michael Niewoehner Cc: John Youn , Felipe Balbi , Heiko Stuebner , Caesar Wang , Tao Huang , Remi Pommarel , Stefan Wahren , Julius Werner , Greg Kroah-Hartman , "linux-usb@vger.kernel.org" , "linux-kernel@vger.kernel.org" Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2960 Lines: 71 Hi, On Sat, Mar 5, 2016 at 12:41 PM, Michael Niewoehner wrote: > Hi Douglas, > Hi John, > > Am 05.03.2016 um 01:33 schrieb Doug Anderson : > >> Michael, >> >> On Fri, Mar 4, 2016 at 4:09 PM, Michael Niewoehner wrote: >>>>> From testing and trying to make sense of the documentation, it appears >>>>> that a 10 ms delay is needed after resetting the core to make sure that >>>>> everything is stable and consistent. Let's add it. >>>>> >>>>> In my testing (on rk3288) this allows us to revert commit >>>>> 192cb07f7928 ("usb: dwc2: Fix probe problem on bcm2835"). Though I >>>>> could never reproduce the problems on my board, this might also allow us >>>>> to revert commit bd84f4ae9986 ("usb: dwc2: Add extra delay when forcing >>>>> dr_mode"). >>>>> >>>>> Signed-off-by: Douglas Anderson >>>> >>>> Tested-by: Michael Niewoehner >> >> Thanks! That's great news! >> >> >>>> I’m a bit confused since git log says bd84f4ae9986 has been merged in 62718e304aa6 but looking at drivers/usb/dwc2/core.c it seems the patch has not been applied anyways ... >>>> However, I tested you your two patches with „magically reverted“ bd84f4ae9986 (msleep 50) on rk3188. >>>> The sdcard keeps being detected and boots just fine. >>> I meant usb stick of course… too much sdcards in my head today \o/. >> >> Odd. It looks to be there for me... >> >> $ git checkout 62718e304aa6 >> HEAD is now at 62718e304aa6... Merge tag 'usb-4.5-rc6' of >> git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb >> >> $ git grep -C3 "NOTE: This is required" -- drivers/usb/dwc2/core.c >> drivers/usb/dwc2/core.c- } >> drivers/usb/dwc2/core.c- >> drivers/usb/dwc2/core.c- /* >> drivers/usb/dwc2/core.c: * NOTE: This is required for some >> rockchip soc based >> drivers/usb/dwc2/core.c- * platforms. >> drivers/usb/dwc2/core.c- */ >> drivers/usb/dwc2/core.c- msleep(50); > > I unfortunately have bad news. > After some more testing it turned out that usb does NOT work (always) on rk3188 when reverting bd84f4ae9986. > It looks like that is dependent on which device / vendor is plugged in. > The usb stick I tested yesterday worked once but today just blinks shortly and then stops working. > Another usb stick I tested today doesn’t blink or work at all. Maybe I should have tested booting some more times :-( Just to clarify based on IRC conversation on #linux-rockchip: * My two patches work fine as per Michael (c0d3z3r0) and another person (mrjay). * My two patches _don't_ also allow us to revert to "50 ms" commit bd84f4ae9986 ("usb: dwc2: Add extra delay when forcing dr_mode"). This is Michael's "bad news". That means we could apply my two patches and the continue to work separately to figure out how to revert commit bd84f4ae9986 ("usb: dwc2: Add extra delay when forcing dr_mode"). Thanks! -Doug