From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751574AbaANNph (ORCPT ); Tue, 14 Jan 2014 08:45:37 -0500 Received: from mezzanine.sirena.org.uk ([106.187.55.193]:53957 "EHLO mezzanine.sirena.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751318AbaANNpe (ORCPT ); Tue, 14 Jan 2014 08:45:34 -0500 Date: Tue, 14 Jan 2014 13:45:28 +0000 From: Mark Brown To: Geert Uytterhoeven Cc: linux-spi@vger.kernel.org, "linux-kernel@vger.kernel.org" , Geert Uytterhoeven Message-ID: <20140114134528.GG15567@sirena.org.uk> References: <1389699411-29135-1-git-send-email-geert@linux-m68k.org> <20140114125242.GE15567@sirena.org.uk> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="+1TulI7fc0PCHNy3" Content-Disposition: inline In-Reply-To: X-Cookie: Marriage is the sole cause of divorce. User-Agent: Mutt/1.5.21 (2010-09-15) X-SA-Exim-Connect-IP: 94.175.92.69 X-SA-Exim-Mail-From: broonie@sirena.org.uk Subject: Re: [PATCH/RFC] spi: core: Fix logic mismatch in spi_master.set_cs() X-SA-Exim-Version: 4.2.1 (built Mon, 26 Dec 2011 16:24:06 +0000) X-SA-Exim-Scanned: Yes (on mezzanine.sirena.org.uk) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --+1TulI7fc0PCHNy3 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Tue, Jan 14, 2014 at 02:23:37PM +0100, Geert Uytterhoeven wrote: > On Tue, Jan 14, 2014 at 1:52 PM, Mark Brown wrote: > >On Tue, Jan 14, 2014 at 12:36:51PM +0100, Geert Uytterhoeven wrote: > > This also pushes the handling of CS_HIGH back out into the driver which > > doesn't seem like it's helping anything. Flipping the sense of enable > It depends: on hardware with separate register bits for chip select polarity > and chip select assertion it avoids having to invert the enable value a second > time. If we're manually setting /CS it really makes no difference what the chip thinks the polarity is - something that is controlling /CS autonomously can't implement this operation and something that can just set it at any time doesn't need to worry if the chip thinks it's asserted or not. > > when calling set_cs() is probably OK though. > Just flipping the sense of enable still needs a documentation update. Huh? Why were you updating the code then... --+1TulI7fc0PCHNy3 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.22 (GNU/Linux) iQIcBAEBAgAGBQJS1T91AAoJELSic+t+oim9tIwP/2/SgvM2l05oxvTaRmpUMjvP c20RIruqXkijo0g9QoNPHVAK65dk3S5TuPwo61f/T8LPQ8brA3g/x1y1AbHs7UhU 0q2+vZJ9y0WnwP+8Mh6O401TcnMlspAYJ02e6U+fNCx9eHvDAsz/eIxIDr2Q8uuy LIWQRaF+HSHzO8OhWs6Ce8Jlk3hCw5AJQDqs8El3oa4ZQVBACkyxo1o8/YknVn5V KyFQ5DW+UsFePI1uPHs27itYSS608Yr1nfgn2JPlMx+en7jEfPAk7hJm7FaZHfO9 N65LfUYr4PjGBbVLxbd8Fo/v76lbOhpyJpyIpre3FTeD4Kw6G66wEe/qd9Y+XvVd 9cvFRY0mGPW1S6WPCnJ+cB+a4Ot0V5kQnYfUqrEeOD32rQizHTG6hfpT0JWF+xeG A5q78wadsdcVp9zraHWbw16r5bJmi4cCr6DOxbgwpMJ9Ev3CVfZRqWSyUci62jjL 2Ai2QEfm364z9PhxGk/sC5Nu7CKott5z6qgQrAL+eD7fLf24ce+t1gHWOBVUf/+F iGU4wP9Njz3sPnAC/yzFqDmNqV/AMxuvA9ngM9wqD3pehKmXm3gGpxhxVZa+YOxr 5mtnhTfkAti+uo+aYlpsTikMvBDiMY4iDOBrrgDaTW6FvvtSroASNZFfhYbiGve4 UxapnPH/NefQKzE+2E8J =rdbn -----END PGP SIGNATURE----- --+1TulI7fc0PCHNy3--