From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ben Dooks Subject: Re: [PATCH v3 2/2] i2c: Davinci i2c bus recovery procedure to clear the bus Date: Tue, 26 Jan 2010 14:46:47 +0000 Message-ID: <20100126144647.GG12774@fluff.org.uk> References: <1263295036.3437.17.camel@localhost.localdomain> <20100124150741.GA28675@fluff.org.uk> <1264431608.3430.19.camel@localhost.localdomain> <87636p4v9l.fsf@deeprootsystems.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <87636p4v9l.fsf-1D3HCaltpLuhEniVeURVKkEOCMrvLtNR@public.gmane.org> Sender: linux-i2c-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Kevin Hilman Cc: Philby John , Ben Dooks , "davinci-linux-open-source-VycZQUHpC/PFrsHnngEfi1aTQe2KTcn/@public.gmane.org" , linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-i2c@vger.kernel.org On Mon, Jan 25, 2010 at 03:31:02PM -0800, Kevin Hilman wrote: > Philby John writes: > > > On Sun, 2010-01-24 at 15:07 +0000, Ben Dooks wrote: > >> On Tue, Jan 12, 2010 at 04:47:16PM +0530, Philby John wrote: > >> > >From 2565eeda807e49376298ec895a0d9a91a7668417 Mon Sep 17 00:00:00 2001 > >> > From: Philby John > >> > Date: Mon, 11 Jan 2010 22:39:44 +0530 > >> > Subject: [PATCH 2/2] Davinci i2c bus recovery procedure to clear the bus > >> > > >> > Come out of i2c time out condition by following the > >> > bus recovery procedure outlined in the i2c protocol v3 spec. > >> > The kernel must be robust enough to gracefully recover > >> > from i2c bus failure without having to reset the machine. > >> > This is done by first NACKing the slave, pulsing the SCL > >> > line 9 times and then sending the stop command. > >> > > >> > This patch has been tested on a DM6446 and DM355 > >> > >> Still not sure whether this can be included as a bug-fix or whether > >> it comes under the new feature category. Also, since it has to get > >> new data from the platform whose tree it should really go into. > > > > This fix is for the issue that was reported here > > http://www.mail-archive.com/davinci-linux-open-source-VycZQUHpC/PFrsHnngEfi1aTQe2KTcn/@public.gmane.org/msg13560.html which IMHO is critical. The issue can be replicated easily and without it the user is left with no choice but to reset the target. > > > > Yes, it does depend on [PATCH 1/2] for platform dependent data, would > > fail otherwise. Could you suggest what may I do in this circumstances? > > This patch looks OK to me, and I'm happy to merge it via DaVinci git > for 2.6.34 since it has a compile dependency with PATCH 1/1. > > Ben, if you're OK with that, can I have your Ack and I can merge it? Acked-by: Ben Dooks > Thanks, > > Kevin -- Ben (ben-elnMNo+KYs3YtjvyW6yDsg@public.gmane.org, http://www.fluff.org/) 'a smiley only costs 4 bytes'