Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759639AbcCEAdH (ORCPT ); Fri, 4 Mar 2016 19:33:07 -0500 Received: from mail-vk0-f54.google.com ([209.85.213.54]:35853 "EHLO mail-vk0-f54.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759184AbcCEAdE convert rfc822-to-8bit (ORCPT ); Fri, 4 Mar 2016 19:33:04 -0500 MIME-Version: 1.0 In-Reply-To: <70F71E2A-40AD-4647-850E-5130DF9FB4D4@mniewoehner.de> 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: Fri, 4 Mar 2016 16:33:02 -0800 X-Google-Sender-Auth: FcKfuStx0xGafc6vp43rwjSOOB4 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: 1729 Lines: 40 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);