From mboxrd@z Thu Jan 1 00:00:00 1970 From: Felipe Balbi Subject: Re: [PATCH] i2c: omap: implement bus recovery Date: Mon, 9 Mar 2015 11:39:17 -0500 Message-ID: <20150309163917.GI3739@saruman.tx.rr.com> References: <1424369209-26735-1-git-send-email-balbi@ti.com> Reply-To: Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="hABqaeELJqnDDeDE" Return-path: Content-Disposition: inline In-Reply-To: <1424369209-26735-1-git-send-email-balbi-l0cyMroinI0@public.gmane.org> Sender: linux-i2c-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Felipe Balbi Cc: wsa-z923LK4zBo2bacvFa/9K2g@public.gmane.org, Tony Lindgren , Linux OMAP Mailing List , linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-i2c@vger.kernel.org --hABqaeELJqnDDeDE Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable 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. >=20 > 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. >=20 > Signed-off-by: Felipe Balbi > --- >=20 > Tested with AM437x IDK, AM437x SK, BeagleBoneBlack and Beagle X15 with > 1000 iterations of i2cdetect on all available buses. >=20 > 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 --=20 balbi --hABqaeELJqnDDeDE Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAEBAgAGBQJU/cy1AAoJEIaOsuA1yqREZA0QAIZHLPFagtA+SNSdJ5jb97eW l8HQ3e21MbGAsmGb9i1Moy8sd2DrNbPIWVZmvQqdJnhf7AxEUyffWSPGW9BSxyPm adMvQUN5q7fjUq+3+pVtLJEcnTOG2BPaTO53Y8S2zN+gL0KG3HqIPom6q3zS42Aw llnt/8WI3RrpBZ7jt3P3NAR+UdKVIkuWyHzGSzqu0hoQmGSQ+e64dS/+hH3vnT6Q AYF/rGpYbbTeR5ND+24RUNUQXnMr2nV/uzMQ68Vk04Zlrvd1OWal5dMNzWXcVxSV aWllaj4kC3s0J+5qUVYjn9/dZcbEFMQXCWNWbGm+PwyLOisYyJSwnMNVD9nbxEHY g93u+D4r+IOvUha6YEDpRQlNv3DQgYQQZvkp8HCZVM5/bDtjnQx3kBMIjVHLsE5L 6EhvIY27UU8F3HDQbgVZqVkNPL0x5iGfI+PYTHqZd8fq+abgs0Xg7Mwt6MW8rT4S wwBU6jR2m9VP/MT8lvrlMfrktRBKQAbt1xMRY3xhH7Tp/tJ+JCNDu6jdcqOtZGey giNfj/9mTJtpfBsRBkJJjHT0UTGcTuP2dW3YKc3jW8kaCjD7yGqeyk1h5P3S1ME2 GuqcwKxUGsqKdVPS8n+I5TC3XXTJhzRDZE77q//gYJZrYnNGpByRl/zF9Ul4d+MX ihpDJxWOi/6RNIqj9Mdm =K8CS -----END PGP SIGNATURE----- --hABqaeELJqnDDeDE--