From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754506AbbLAT64 (ORCPT ); Tue, 1 Dec 2015 14:58:56 -0500 Received: from mezzanine.sirena.org.uk ([106.187.55.193]:56513 "EHLO mezzanine.sirena.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751881AbbLAT6y (ORCPT ); Tue, 1 Dec 2015 14:58:54 -0500 Date: Tue, 1 Dec 2015 19:58:16 +0000 From: Mark Brown To: Michal Suchanek Cc: Heiner Kallweit , David Woodhouse , Brian Norris , Han Xu , Boris Brezillon , Javier Martinez Canillas , Stephen Warren , "Andrew F. Davis" , Marek Vasut , =?utf-8?B?UmFmYcWCIE1pxYJlY2tp?= , Mika Westerberg , Gabor Juhos , Bean Huo =?utf-8?B?6ZyN5paM5paM?= , Furquan Shaikh , linux-mtd@lists.infradead.org, linux-kernel@vger.kernel.org, linux-spi@vger.kernel.org Message-ID: <20151201195816.GS1929@sirena.org.uk> References: <8c34c7790244489c2ce0072c72bd9bc7c4cdb965.1448988089.git.hramrach@gmail.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="v98/5hv2LQXhs+5A" Content-Disposition: inline In-Reply-To: <8c34c7790244489c2ce0072c72bd9bc7c4cdb965.1448988089.git.hramrach@gmail.com> X-Cookie: A beer delayed is a beer denied. User-Agent: Mutt/1.5.24 (2015-08-30) X-SA-Exim-Connect-IP: 94.175.94.161 X-SA-Exim-Mail-From: broonie@sirena.org.uk Subject: Re: [PATCH v5 08/10] spi: expose master transfer size limitation. 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 --v98/5hv2LQXhs+5A Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Tue, Dec 01, 2015 at 04:51:06PM -0000, Michal Suchanek wrote: > On some SPI controllers it is not feasible to transfer arbitrary amount > of data at once. >=20 > When the limit on transfer size is a few kilobytes at least it makes > sense to use the SPI hardware rather than reverting to gpio driver. > + /* > + * on some hardware transfer size may be constrained > + * the limit may depend on device transfer settings > + */ > + size_t (*max_transfer_size)(struct spi_device *spi); Heiner submitted a *very* similar patch just now with a straight variable plus accessor instead of a function and using a name with _msg. I'm ambivalent on the implementation but prefer the naming here since that's more the limitation we're trying to express I think (some hardware does have limiations about multple transfers too). Can the two of you come up with something that works for both of you? --v98/5hv2LQXhs+5A Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iQEcBAEBCAAGBQJWXfvYAAoJECTWi3JdVIfQ+csH/jQoupku0nMby5MfE9iDpwif jN/8jQm3WpdH7oGihAYfqmCLyAdEKuACkqrCLuE5X0a4qJB3aqjsOm6aAT5P+nL1 GTTLGJ1RDdStgiyyFbyfW9CUL4ltvKt4Cefi7DozO+xXQaOheW0VwHG8HkfSX5fZ PPHIF82+NexFIpJANK4bRvsZGhtLiHS3LRjm5n/pHsrLZAbzJqPMRSIGd485B0Tx jvWNV1Nzz4ZWAq5Od7HTFl9y91x/9Mxjura2YilV0+vfVwkYGWcPMCOOzk5va8C7 RHjSNCRt69TljR6kS1oPpUZQWW8ADhaebfLkNFLW4mQ5dTuFHqcYeS+SXCH2H+c= =70ge -----END PGP SIGNATURE----- --v98/5hv2LQXhs+5A-- From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mark Brown Subject: Re: [PATCH v5 08/10] spi: expose master transfer size limitation. Date: Tue, 1 Dec 2015 19:58:16 +0000 Message-ID: <20151201195816.GS1929@sirena.org.uk> References: <8c34c7790244489c2ce0072c72bd9bc7c4cdb965.1448988089.git.hramrach@gmail.com> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="v98/5hv2LQXhs+5A" Cc: Heiner Kallweit , David Woodhouse , Brian Norris , Han Xu , Boris Brezillon , Javier Martinez Canillas , Stephen Warren , "Andrew F. Davis" , Marek Vasut , =?utf-8?B?UmFmYcWCIE1pxYJlY2tp?= , Mika Westerberg , Gabor Juhos , Bean Huo =?utf-8?B?6ZyN5paM5paM?= , Furquan Shaikh , linux-mtd-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-spi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Michal Suchanek Return-path: Content-Disposition: inline In-Reply-To: <8c34c7790244489c2ce0072c72bd9bc7c4cdb965.1448988089.git.hramrach-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> Sender: linux-spi-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: --v98/5hv2LQXhs+5A Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Tue, Dec 01, 2015 at 04:51:06PM -0000, Michal Suchanek wrote: > On some SPI controllers it is not feasible to transfer arbitrary amount > of data at once. >=20 > When the limit on transfer size is a few kilobytes at least it makes > sense to use the SPI hardware rather than reverting to gpio driver. > + /* > + * on some hardware transfer size may be constrained > + * the limit may depend on device transfer settings > + */ > + size_t (*max_transfer_size)(struct spi_device *spi); Heiner submitted a *very* similar patch just now with a straight variable plus accessor instead of a function and using a name with _msg. I'm ambivalent on the implementation but prefer the naming here since that's more the limitation we're trying to express I think (some hardware does have limiations about multple transfers too). Can the two of you come up with something that works for both of you? --v98/5hv2LQXhs+5A Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iQEcBAEBCAAGBQJWXfvYAAoJECTWi3JdVIfQ+csH/jQoupku0nMby5MfE9iDpwif jN/8jQm3WpdH7oGihAYfqmCLyAdEKuACkqrCLuE5X0a4qJB3aqjsOm6aAT5P+nL1 GTTLGJ1RDdStgiyyFbyfW9CUL4ltvKt4Cefi7DozO+xXQaOheW0VwHG8HkfSX5fZ PPHIF82+NexFIpJANK4bRvsZGhtLiHS3LRjm5n/pHsrLZAbzJqPMRSIGd485B0Tx jvWNV1Nzz4ZWAq5Od7HTFl9y91x/9Mxjura2YilV0+vfVwkYGWcPMCOOzk5va8C7 RHjSNCRt69TljR6kS1oPpUZQWW8ADhaebfLkNFLW4mQ5dTuFHqcYeS+SXCH2H+c= =70ge -----END PGP SIGNATURE----- --v98/5hv2LQXhs+5A-- -- To unsubscribe from this list: send the line "unsubscribe linux-spi" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html