From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932242AbaAUSVk (ORCPT ); Tue, 21 Jan 2014 13:21:40 -0500 Received: from mezzanine.sirena.org.uk ([106.187.55.193]:57667 "EHLO mezzanine.sirena.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932183AbaAUSVf (ORCPT ); Tue, 21 Jan 2014 13:21:35 -0500 Date: Tue, 21 Jan 2014 18:21:30 +0000 From: Mark Brown To: Geert Uytterhoeven Cc: linux-spi@vger.kernel.org, linux-kernel@vger.kernel.org, Geert Uytterhoeven Message-ID: <20140121182130.GM17314@sirena.org.uk> References: <1390317009-8292-1-git-send-email-geert@linux-m68k.org> <1390317009-8292-4-git-send-email-geert@linux-m68k.org> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="QvYscaK3qHF14stx" Content-Disposition: inline In-Reply-To: <1390317009-8292-4-git-send-email-geert@linux-m68k.org> X-Cookie: We have DIFFERENT amounts of HAIR -- 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 4/5] spi: Check that Quad/Dual is half duplex 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 --QvYscaK3qHF14stx Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Tue, Jan 21, 2014 at 04:10:08PM +0100, Geert Uytterhoeven wrote: > From: Geert Uytterhoeven >=20 > Quad and Dual SPI Transfers use all available data lines (incl. MOSI/MISO= ), > hence they must be half duplex. Add a check that verify that. This is surprising to me - I had expected that there would be extra signals that would be used for these modes, not that the opposite direction data line would be one of the ones being reused. On the other hand if this is what all the flash chips do then it would seem reasonable that controllers do the same. Can you clarify please? --QvYscaK3qHF14stx Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.22 (GNU/Linux) iQIcBAEBAgAGBQJS3rqnAAoJELSic+t+oim9+sQQAJYLmkPiu2NJ3T3BGIkzJs3j yi5O8Vi0yNjx+PIh6H/LVcqhCrIUEgWQqg1wM0YidxUkc2Z/GP7VEM4tocitVkky TloJvedbxDLd4J6iXitSvomSG+4xc5MjkTUCP1rSS58vj0hB1b1xEdOAwyw6knMK OlOhPyfZsjW9CzfLiUhS7Bull7qmclefBLZqYDlpSuuVk6VMB6mWrn8svHrPBEn1 jQ+pAJRlECEXjktPmRB6q2jxF/C17VFrHy7D+E8R648lZvnbT67NbEDdsYCBzom+ krYqAjpjtV+fMUOOQhV3DDv0oWxDVfqOfzCINHwC3vxq/XMMpNTjC1BBuxSmWdhD 2VA2DARnXIos0VuxgK7naBHI+qzWsdwDPGeas0kNbKxR3+AmhAtRAnINtTDjMN3d FkNezKkwP8IOI8qGtkabJUTs/THjE5p/uoUWezN/e//wVOhIOb9gRPxQYg4kz70F BfZEd7E1r38oo6TPqd2X0X8nxeOUfe58S+ZVVX/5P7Gw3pXXFBk/ABqpoxOiFkGZ Bta7rkyrAWnHX5HSm/FpiTSYSflP58P4jbnV11uIXriKwExdnHOJWI8liWjZW4DC 7fHvQG+ziEVs77ULSjjUfUU8J4ee9nSpbgAfxgmQjm8BFQJN7ELheJfXHILWHUsP MalsosmQxaOWsC+523aP =g917 -----END PGP SIGNATURE----- --QvYscaK3qHF14stx--