From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Munegowda, Keshava" Subject: Re: [PATCH] OMAP: USB : Fix the EHCI enumeration and core retention issue Date: Fri, 6 Jul 2012 15:30:44 +0530 Message-ID: References: <87fw9o32v2.fsf@ti.com> <20120622103050.GG28472@arwen.pp.htv.fi> <87ehp71liv.fsf@ti.com> <20120622203645.GD29290@arwen.pp.htv.fi> <87d34nfdei.fsf@ti.com> <871uku85o8.fsf@ti.com> <87k3yj4pn4.fsf@ti.com> <20120705111901.GR22065@sortiz-mobl> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Return-path: Received: from na3sys009aog114.obsmtp.com ([74.125.149.211]:51821 "EHLO na3sys009aog114.obsmtp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751309Ab2GFKAs (ORCPT ); Fri, 6 Jul 2012 06:00:48 -0400 Received: by lbbgg6 with SMTP id gg6so13716452lbb.36 for ; Fri, 06 Jul 2012 03:00:44 -0700 (PDT) In-Reply-To: <20120705111901.GR22065@sortiz-mobl> Sender: linux-omap-owner@vger.kernel.org List-Id: linux-omap@vger.kernel.org To: Samuel Ortiz Cc: Kevin Hilman , balbi@ti.com, linux-omap@vger.kernel.org, linux-usb@vger.kernel.org, notasas@gmail.com, Paul Walmsley On Thu, Jul 5, 2012 at 4:49 PM, Samuel Ortiz wrote: > Hi Kevin, Keshava, > > On Wed, Jul 04, 2012 at 06:33:35AM -0700, Kevin Hilman wrote: >> "Munegowda, Keshava" writes: >> >> > On Tue, Jul 3, 2012 at 12:17 PM, Munegowda, Keshava >> > wrote: >> >> On Mon, Jul 2, 2012 at 10:24 PM, Kevin Hilman wrote: >> >>> Felipe, Keshava, >> >>> >> >>> Kevin Hilman writes: >> >>> >> >>>> Felipe Balbi writes: >> >>>> >> >>>> [...] >> >>>> >> >>>>> Keshava is reverting a fix for a HW errata. I can't accept it as it will >> >>>>> cause regressions. Granted, regression by regression, there's no change, >> >>>>> but I simply can't knowingly cause a regression to the driver just to >> >>>>> have PM working. We need a real fix for this issue. >> >>>> >> >>>> Sure, as long as there is a fix in this -rc cycle. >> >>>> >> >>>> This driver intoduced changes in v3.5 that break PM for the whole SoC >> >>>> (by preventing CORE retention.) These changes were clearly not tested >> >>>> with PM. >> >>>> >> >>>> If you cannot fix this during the -rc cycle, then you need to revert the >> >>>> driver PM changes that broke PM for the *whole* SoC. >> >>> >> >>> What's the status of this regression? >> >>> >> >>> This is still broken in v3.5-rc and is preventing CORE retention for the >> >>> *whole* SoC. >> >>> >> >>> Please fix this, either with a proper fix, or a revert for 3.5-rc. >> >> >> >> >> >> The proper fix for this is implement ion of ehci remote wakeup through >> >> I/O chain handler; it takes time. >> >> As Felipe also mentioned, This patch is OK for now. >> > >> > Sorry, Felipe still insist not to revert this patch, but to change >> > this patch requires quite more changes in the usbhs core >> > and we need to see the how the hub control changes need to be brought >> > in to usbhs core. so , reverting is the >> > best solution to time being. >> > >> > Its observed that ehci was enabled after linux kernal version 3.3 ; >> > before that even though driver was there >> > the ehci deriver was disabled by defaults; and it is expected the >> > people who want to use NFS then can enable it >> > explicitly. >> > >> > so, the solution is >> > >> > 1. Use this patch ( reverting the hw errata ) to fix the NFS Boot and >> > suspend/resume crash >> >> Or, use the patches from Russ Dill where were more targetted fixes. >> Either way, I'm OK with that. > Keshava, I'll wait for your decision here to know which patch you want me to > take. > > > >> > 2. Disable the ehci driver to make the pm work in idle case ; >> > This configuration should exist till the ehci remote >> > wakeup implementation completes. >> >> Yes. Please disabled it by default. >> >> Until PM in this driver can work without breaking PM for the whole SoC, >> it should remain disabled. > So, I should expect another patch here as well. > FYI, I was planning to send a pull request for MFD 3.5 fixes to Linus > tomorrow, but I'll wait for you. Hopefully I should be able to send it on > Monday. > > Cheers, > Samuel. Thanks Samuel I will send the patches today. regards keshava