From mboxrd@z Thu Jan 1 00:00:00 1970 From: Wolfram Sang Subject: Re: [PATCH] i2c: omap: implement bus recovery Date: Wed, 11 Mar 2015 16:22:50 +0100 Message-ID: <20150311152249.GA15562@katana> References: <1424369209-26735-1-git-send-email-balbi@ti.com> <20150309163917.GI3739@saruman.tx.rr.com> <20150311015004.GB21726@saruman.tx.rr.com> <55004789.7080706@ti.com> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="/9DWx/yDrRhgMJTb" Return-path: Content-Disposition: inline In-Reply-To: <55004789.7080706@ti.com> Sender: linux-omap-owner@vger.kernel.org To: Grygorii Strashko Cc: balbi@ti.com, Tony Lindgren , Linux OMAP Mailing List , linux-i2c@vger.kernel.org List-Id: linux-i2c@vger.kernel.org --/9DWx/yDrRhgMJTb Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Wed, Mar 11, 2015 at 03:47:53PM +0200, Grygorii Strashko wrote: > Hi Felipe, >=20 > On 03/11/2015 03:50 AM, Felipe Balbi wrote: > >On Mon, Mar 09, 2015 at 11:39:17AM -0500, Felipe Balbi wrote: > >>On Thu, Feb 19, 2015 at 12:06:49PM -0600, Felipe Balbi wrote: > >>>If either SCL or SDA are stuck low, we need to > >>>recover the bus using the procedure described > >>>on section 3.1.16 of the I2C specification. > >>> > >>>Note that we're trying to implement the procedure > >>>exactly as described by that section. First we > >>>check which line is stuck low, then implement > >>>one or the other procedure. If SDA recovery procedure > >>>fails, we reset our IP in an attempt to make it work. > >>> > >>>Signed-off-by: Felipe Balbi > >>>--- > >>> > >>>Tested with AM437x IDK, AM437x SK, BeagleBoneBlack and Beagle X15 with > >>>1000 iterations of i2cdetect on all available buses. > >>> > >>>That said, I couldn't get any device to hold the bus busy so I could > >>>see this working. If anybody has any good way of forcing a condition > >>>so that we need bus recovery, I'd be glad to look at. > >> > >>ping > > > >any comments here ?? Anybody at all ???? > > >=20 > I think the I2C bus recovery infrastructure should be used here ;) > As I did there https://lkml.org/lkml/2014/12/1/397, but > there are no comments too :( Sorry, guys, a lot of stuff going on in I2C. Bus recovery needs a more generic look. I'll try, but can't promise for 4.1. If it fails 4.1., it will get priority for 4.2. --/9DWx/yDrRhgMJTb Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAEBAgAGBQJVAF3JAAoJEBQN5MwUoCm2aJ4P/0yicustx36ntEKgx5Nr/zlB 4VBWkpM73JdL9ZRad7GalDxKAYOVXQnl53Q0zyNQ/cb++/UmrNOtLIL/cjYCDwQK lYkk/yo6moqzaP1amT/NSDnPyHSxf5Z3V3c8+tt5gYdQ6uDeNzH+k8SpwGIxvYVN UqL1K7+see1ZyVF1hZCco8j/V8wC8OcHVzpEVcAPtO4OkBTKVPUTTLBASliHIrDO tSOzn/6FA0AU7jdMt0vbGWSXVPZdd0n6M77NaSyAz3lk9dm02Nx7zWj1+iM3Yzbq 4ZTmdFsL9taFKkrwsAyGzxctscwHplbCXW7S8QGGMe4Mppl2/7cyZ6++OLcWLoh4 atJh0E1kaZ+6B/UPBz5weMvgGP128yLz1zIul4VX1U5OZruOHzJ1CQK9Kpu9P9BS rLevuL06OrRc65OHv3jrFijxFwLIU9H15CL6TntMB6TOCV5qsFUzrmhQ0/pN4dUE exKqYCUjWsToAWtkukFM+r9VS5AsP/xHjls5N+YkdEx4sgBB6Yx2tgD5r4ulkBuj 2gFrdcwM4a3igeyJdYfBwffBESOdGjye6NGjJ4ddMr9NnXZuuMgpHO2N3Gyv1Vqg WR0AkPcWBvY3Aqmtr69pfq8tQ5Mc8zrS/fYDVzxbYC3YKqDziWFuZZBz+POHvcEK IOvvCIu33aSNzlVq5yTD =sWb/ -----END PGP SIGNATURE----- --/9DWx/yDrRhgMJTb--