From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mark Brown Subject: Re: Ask for help on SPI slave side driver support Date: Mon, 30 Sep 2013 10:33:17 +0100 Message-ID: <20130930093317.GX19304@sirena.org.uk> References: <23ff6b10.bf1d.1416a88321f.Coremail.youshenghui0322@163.com> <4025277.bhF6fFGQqq@flatron> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="yQ6PUHtvLgXN2OhJ" Return-path: Received: from cassiel.sirena.org.uk ([80.68.93.111]:38869 "EHLO cassiel.sirena.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751809Ab3I3Jdm (ORCPT ); Mon, 30 Sep 2013 05:33:42 -0400 Content-Disposition: inline In-Reply-To: <4025277.bhF6fFGQqq@flatron> Sender: linux-samsung-soc-owner@vger.kernel.org List-Id: linux-samsung-soc@vger.kernel.org To: Tomasz Figa Cc: YouShenghui , linux-samsung-soc@vger.kernel.org, linux-spi@vger.kernel.org --yQ6PUHtvLgXN2OhJ Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Mon, Sep 30, 2013 at 01:20:42AM +0200, Tomasz Figa wrote: > Mark will probably know better, but AFAIK there is no API for slave mode= =20 > SPI available in Linux kernel. Please correct me if I'm wrong. That's correct. > The code mentioned in the post from your link was some internal vendor=20 > code, which is unlikely to be available publicly. However support for=20 > slave mode from hardware side seems more or less similar to master mode,= =20 > which means that assuming you can add some kernel API for it, the=20 > modification to the spi-s3c64xx wouldn't be too big. There were some people working on slave mode (or at least talking about it) but I don't think they ever sent it. It'd probably just be the same as master mode but with transfers triggered from /CS instead of from driver action. The biggest trick would be making sure the transfer is running before the master actually starts sending data. --yQ6PUHtvLgXN2OhJ Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.21 (GNU/Linux) iQIcBAEBAgAGBQJSSUVaAAoJELSic+t+oim9uygP/Rz0qmicpf6CogtUOY6FL9gM iJFxetg9EUyoII0fwI2yhioW5pjU1yRefr4baXq8lW3cFqKVnRmfjA7TIa1QGzRn D2dBHRvwxvMfIpOsTmFA1hBdPcj/5GgarerHFpr+gpRbkBqliLLC1EN9WDHoMJjn wD4q6Gwc0t87f+GhlXt+GH54MgYLno0Jm0wp93brSXtZOs08OxD0eSdsnOPfAqKu 1gmMBv2Jm9smrbGPpNGFXE2Ei7P9RSACUvS1TWNYufkLDrGO7HOJVztn7DUkXpbJ nUdko+106EfbvopcCDsREv6MvNZBUDaJilWx0t4ZfCWabKprL5FM90g1pl8vXkeD xku5qzfXm0a1ZFfziwYmbHFzlft8nblQ/xeNk+c+LwCNWiW8MDrAC1MBPDv+HyKS b1t8F5BMZn+plahxVrVZG7m6pkL5DRdrnx/26rbmvFJAbjcpt/yEfRrwNYrAcvWC mD8VyX+Vhwycv5PlJM25IsFXWUlltJDkDW0dtYYlaDvTY1EAiUJR7+oQCrLfQ+D4 ExKTY1niQxbMv02/V5QncI1fPcDDpSbpaauS6rmlj8KiyiJnjPeEPls8JX9vEx7t dNL91Z1wwgVjYuCpK5OEz6erMm12OV9ooZYsmLMKToPACJEzkdONvFZuFOI+3J8/ KmGEBrQK4O2LHfWzsVX0 =nvC5 -----END PGP SIGNATURE----- --yQ6PUHtvLgXN2OhJ--