From mboxrd@z Thu Jan 1 00:00:00 1970 From: Wolfram Sang Subject: Re: [PATCH 1/2] i2c-mv64xxx: Fix timing issue on Armada XP (errata FE-8471889) Date: Fri, 14 Jun 2013 17:24:30 +0200 Message-ID: <20130614152430.GF2929@katana> References: <1370620140-17177-1-git-send-email-gregory.clement@free-electrons.com> <1370620140-17177-2-git-send-email-gregory.clement@free-electrons.com> <20130607182500.10593e73@skate> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="FoLtEtfbNGMjfgrs" Return-path: Content-Disposition: inline In-Reply-To: <20130607182500.10593e73@skate> Sender: linux-i2c-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Thomas Petazzoni Cc: Gregory CLEMENT , linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Ezequiel Garcia , Sebastian Hesselbarth , linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, Jason Cooper , Andrew Lunn , Nicolas Pitre , Lior Amsalem , Maen Suleiman , Tawfik Bayouk , Shadi Ammouri , Eran Ben-Avi , Yehuda Yitschak , Nadav Haklai , Ike Pan , Chris Van Hoof , Dan Frazier , Leif Lindholm , Jon Masters , David Marlin , linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Zbigniew Bodek List-Id: linux-i2c@vger.kernel.org --FoLtEtfbNGMjfgrs Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Fri, Jun 07, 2013 at 06:25:00PM +0200, Thomas Petazzoni wrote: > Dear Gregory CLEMENT, >=20 > On Fri, 7 Jun 2013 17:48:59 +0200, Gregory CLEMENT wrote: >=20 > > +/* > > + * 5us delay in order to avoid repeated start > > + * timing violation on Armada XP SoC. > > + */ > > +static int mv64xxx_i2c_errata_delay; >=20 > This should probably be a per-I2C controller variable, i.e in > mv64xxx_i2c_data. Yes. >=20 >=20 > > + if (!mv64xxx_i2c_errata_delay && > > + of_machine_is_compatible("marvell,armadaxp")) > > + mv64xxx_i2c_errata_delay =3D 1; >=20 > I am wondering whether it should be done this way, or using a separate > DT property. Need to think about it. It is similar to the sda-hold-time issue, I guess. --FoLtEtfbNGMjfgrs Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.12 (GNU/Linux) iQIcBAEBAgAGBQJRuzWuAAoJEBQN5MwUoCm2M8cQAJepjpVlRj7NGrxK0gWpZ08C 6X5SNTywQWxOi1yR64huBo2gx/J2ku361l9KWY932HXEDVKNGtEY4zbPHu/DKLSk MsvbIkxNFKf9TCeJIUVQfQpH4qQt41gP/HIoOeRd8AVzEe3V8LrcGhSjJlv4xojs rvXt2CdD+oMzrwnaphhG+U6oJTprRLpgcuPjs7KqV5jc3mdnB7e8ivMF+sj8aNUs ucmtb0V0CGGvUUD9GWE3txRB0MfXgmTYYBKoOQza0I6bkRbkakIHz9xk2b/zBDRC CyNmR6TU/Twu4k+edrwymFdMc9WUM5w2ntJV0STaTgnqRy9UT3lmPdbhPbpBBK9E 0iyCe/yV4A/Iy3ZvFdMc1h1iKenSPKRFSMoIC7D/YpqMP3eo01WRb3eaOOpPHW4T Y6zyGPC7F+wkigYOdqOab48otFz6bJCZXMee/jp/zZZnfO05KybP9YTq+4g43+uU 1U/iV2ARR54Z7W4lpObdMAdU6FRDf80IjuNEx58l0EZStHYv85Viqz8pX/LXPKqZ GP+rDiYcKVy8Trz0lDdDtja2u5KhJh0+BT/K8jmrqWOc2UkIRqnoiqaSLZxkBAIJ F4JwHgHUf2stMDZvnzGcUbXtNjMiylH3jV5QmUoQ5Rl9z/0oON4xc4SEn9Re7Esq ZA++QwCyZ2uNAUDMlYXs =87T6 -----END PGP SIGNATURE----- --FoLtEtfbNGMjfgrs--