Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751921AbaKVNWA (ORCPT ); Sat, 22 Nov 2014 08:22:00 -0500 Received: from sauhun.de ([89.238.76.85]:60889 "EHLO pokefinder.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751484AbaKVNV6 (ORCPT ); Sat, 22 Nov 2014 08:21:58 -0500 Date: Sat, 22 Nov 2014 14:23:09 +0100 From: Wolfram Sang To: Felipe Balbi Cc: Alexander Kochetkov , linux-omap@vger.kernel.org, linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org, Tony Lindgren Subject: Re: [PATCH 2/4] i2c: omap: implement workaround for handling invalid BB-bit values Message-ID: <20141122132309.GC2679@katana> References: <1416518925-20679-1-git-send-email-al.kochet@gmail.com> <1416518925-20679-3-git-send-email-al.kochet@gmail.com> <20141121160808.GM7508@saruman> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="XMCwj5IQnwKtuyBG" Content-Disposition: inline In-Reply-To: <20141121160808.GM7508@saruman> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --XMCwj5IQnwKtuyBG Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Fri, Nov 21, 2014 at 10:08:08AM -0600, Felipe Balbi wrote: > On Fri, Nov 21, 2014 at 01:28:43AM +0400, Alexander Kochetkov wrote: > > In a multimaster environment, after IP software reset, BB-bit value doe= sn't > > correspond to the current bus state. It may happen what BB-bit will be = 0, > > while the bus is busy due to another I2C master activity. > >=20 > > Any transfer started when BB=3D0 and bus is busy wouldn't be completed = by IP > > and results in controller timeout. More over, in some cases IP could > > interrupt another master's transfer and corrupt data on wire. > >=20 > > The commit implement method allowing to prevent IP from entering into > > "controller timeout" state and from "data corruption" state. > >=20 > > The one drawback is the need to wait for 10ms before the first transfer. > >=20 > > Tested on Beagleboard XM C. > >=20 > > Signed-off-by: Alexander Kochetkov >=20 > Tested on BBB and AM437x Starter Kit >=20 > Tested-by: Felipe Balbi > Reviewed-by: Felipe Balbi Huh, I can't apply this one? Which kernel version is this based on? --XMCwj5IQnwKtuyBG Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAEBAgAGBQJUcI49AAoJEBQN5MwUoCm2Ba8P/0imzQrZvoLx7zKI+v5UpV1f mFRmNH5X7yvAhbt3dao6/hJ3hSs1x7wJp+momIObCXGhNZepzrqEdENPqKNnnx2f v30nl18b9Gt43D+DjzD7qLNlvlhNleKMUC4auXYnfmi2BuarMbVWY+ug7KcIPL2e WVyzRUejWoY3nbTkCnuinu9cGTUDH2+R2Ve6WIuIcV5n7uASgNYK+XAJf0Y3wXmu TeFJwV9tDEWcD32Fmdf0Vmfy1BaO8fz6KGkJ33rXG5E+O+QIH+ps96jKakMS27eZ pThbihzEs+tMK16Lwbg+qUA8TS3QSyvYLPI6Tk5/OUVs6qDxiWKUHoBynjNMczp8 xtB2rl7YDvg1irwhevuh2ZQjVi+a+ceflejOca7zy9QBgtO2X2dMIM34UwL0OH2H 4ayFM6SSKPWJjvoRcVQIA5dMAX3VZ6hmtxkVuZWAAi0bhvOTvvdqFklshPYbL2um uIh3uR+b8gRNvnao4LkI/To0LCUaa/8gFHG9UQHT3bb7BPToCH0ZUleJE6paYOx8 TUWf3PmTnS/wd//gaqb7QkPrxd3088HvIGl7lAe0qMeokoTpusUMmrVTRAvm5Zq9 4T75IHh0sE0TgVOAGgbkaELdv9lIiU1Wl52KOEi0MssgFqM93GZyvFangC02MBRI Exghg2WSfXCYtqwbYWrD =zLD2 -----END PGP SIGNATURE----- --XMCwj5IQnwKtuyBG-- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/