From mboxrd@z Thu Jan 1 00:00:00 1970 From: Samuel Ortiz Subject: Re: [PATCH] OMAP: USB : Fix the EHCI enumeration and core retention issue Date: Thu, 5 Jul 2012 13:19:01 +0200 Message-ID: <20120705111901.GR22065@sortiz-mobl> 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> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from mga02.intel.com ([134.134.136.20]:10262 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752778Ab2GELHj (ORCPT ); Thu, 5 Jul 2012 07:07:39 -0400 Content-Disposition: inline In-Reply-To: <87k3yj4pn4.fsf@ti.com> Sender: linux-omap-owner@vger.kernel.org List-Id: linux-omap@vger.kernel.org To: Kevin Hilman Cc: "Munegowda, Keshava" , balbi@ti.com, linux-omap@vger.kernel.org, linux-usb@vger.kernel.org, notasas@gmail.com, Paul Walmsley 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. -- Intel Open Source Technology Centre http://oss.intel.com/