Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756467AbZD0Ntu (ORCPT ); Mon, 27 Apr 2009 09:49:50 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753383AbZD0Ntl (ORCPT ); Mon, 27 Apr 2009 09:49:41 -0400 Received: from intcomgrp.com ([216.54.13.120]:46104 "EHLO beta.intcomgrp.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1752136AbZD0Ntk (ORCPT ); Mon, 27 Apr 2009 09:49:40 -0400 Message-ID: <49F5B774.5010501@beta.intcomgrp.com> Date: Mon, 27 Apr 2009 09:47:32 -0400 From: James Kosin Organization: International Communications Group, Inc. User-Agent: Thunderbird 2.0.0.21 (Windows/20090302) MIME-Version: 1.0 To: Mark Brown CC: Pavel Machek , Mike Rapoport , linux-kernel@vger.kernel.org, Liam Girdwood Subject: Re: [RFD] voltage/current regulator consumer interface References: <49EC9709.8070002@support.intcomgrp.com> <49ED628A.4000505@compulab.co.il> <49EDC935.7080308@beta.intcomgrp.com> <49EDD2A7.9090300@compulab.co.il> <20090425081933.GE2428@ucw.cz> <20090425090448.GA4210@sirena.org.uk> In-Reply-To: <20090425090448.GA4210@sirena.org.uk> X-Enigmail-Version: 0.95.7 OpenPGP: id=7BB59129 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="------------enigE3DA2232FBA0E1049BC3B60A" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2434 Lines: 61 This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enigE3DA2232FBA0E1049BC3B60A Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Mark Brown wrote: > On Sat, Apr 25, 2009 at 10:19:33AM +0200, Pavel Machek wrote: >=20 >> Well, then you should teach serial driver to power the (GPS) device up= on >> open() and power it off on close()... >=20 > This all started because this approach was nacked for serial drivers. > In any case, I'm not sure that'll scale - it may not be desirable or > reasonable to do something like that for all devices. For example, the= > devices may be connected via a technology that's not suitable (I've > worked on systems which used ethernet here). >=20 Ethernet can be treated as a serial interface as well down to the simplest level. I'm leaving out a lot is making this assumption; but, it is true to a fault. Scalability has more to do with the generic interface you use... If you tie things to ttySxx and don't allow configuration parameters you are also restricting the usage and scalability as well. The GPS should be configurable so the interface is generic and allows getting from Ethernet/PCI/IDE/serial/parallel/etc. The transport layer should not matter to the GPS driver. The trick will be to allow the user to ultimately choose, if that is what you want. The same applies to disk devices, now we have IDE/SATA/etc. the disk device itself doesn't depend on the interface physically, the kernel treats all these as suitable interfaces for disk/CDROM/tape devices and the world is not turned on its ear just because there is a different physical interface. James --------------enigE3DA2232FBA0E1049BC3B60A Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.9 (MingW32) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iEYEARECAAYFAkn1t30ACgkQkNLDmnu1kSmhFQCfchPq8bFRmBRlclfLPMU4IgV6 l0YAni/zaHki0l4l3AUpxpk0dlHLvX5k =SpOh -----END PGP SIGNATURE----- --------------enigE3DA2232FBA0E1049BC3B60A-- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/