From mboxrd@z Thu Jan 1 00:00:00 1970 From: Laxman Dewangan Subject: Re: State of arbitration and i2c_gpio? Date: Mon, 16 Jul 2012 21:35:38 +0530 Message-ID: <50043BD2.9030505@nvidia.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: Sender: linux-i2c-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Matthias Urlichs Cc: "linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , Viresh Kumar List-Id: linux-i2c@vger.kernel.org Hi Matthias, I remember Viresh was working on this support sometimes ago where he=20 added gpio based arbitration recovery on i2c-core. http://lwn.net/Articles/485046/ I am also looking to use the gpio based arb recovery mechanism for the=20 i2c-tegra.c. As this recovery will be generic, better to have this in common place s= o=20 that many driver can use this. Also the provision should be there to=20 configure pin as gpio and non-gpio mode. Thanks, Laxman On Monday 16 July 2012 08:45 PM, Matthias Urlichs wrote: > Hello people, > > I'd like to ask whether anybody is working on adding arbitration supp= ort to > i2c_algo_bit.c. The code still has the old "FIXME do arbitration here= " comments, > added five years ago when the I=C2=B2C was imported into Linux 2.3.34= pre1. :-/ > > If not, and I'm going to have to do that myself =E2=80=A6 my main que= stion is, even > before I get to that -- how do I even detect that the bus is idle? Tu= rn > interrupts off and busy-loop-check that both SCL and SDA stay high fo= r at least > one and a half clock periods? > > Ugh. > -----------------------------------------------------------------------= ------------ This email message is for the sole use of the intended recipient(s) and= may contain confidential information. Any unauthorized review, use, disclosure or = distribution is prohibited. If you are not the intended recipient, please contact t= he sender by reply email and destroy all copies of the original message. -----------------------------------------------------------------------= ------------