Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754121Ab3GIO4I (ORCPT ); Tue, 9 Jul 2013 10:56:08 -0400 Received: from cassiel.sirena.org.uk ([80.68.93.111]:40349 "EHLO cassiel.sirena.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753864Ab3GIO4D (ORCPT ); Tue, 9 Jul 2013 10:56:03 -0400 Date: Tue, 9 Jul 2013 15:55:10 +0100 From: Mark Brown To: Maxime Ripard Cc: Arnd Bergmann , Greg Kroah-Hartman , David Woodhouse , Artem Bityutskiy , Shawn Guo , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, oliver@schinagl.nl, linux-mtd@lists.infradead.org, Wolfram Sang , Jean Delvare , linux-i2c@vger.kernel.org Message-ID: <20130709145510.GZ27646@sirena.org.uk> References: <20130705201118.GM2959@lukather> <5811519.oHVuMujf0I@wuerfel> <20130706120112.GA11069@lukather> <8997501.Dchyii8uWX@wuerfel> <20130708083426.GO27646@sirena.org.uk> <20130708202538.GK11243@lukather> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="3aDtFGIaURYlkDgg" Content-Disposition: inline In-Reply-To: <20130708202538.GK11243@lukather> X-Cookie: You will contract a rare disease. User-Agent: Mutt/1.5.21 (2010-09-15) X-SA-Exim-Connect-IP: 193.120.41.114 X-SA-Exim-Mail-From: broonie@sirena.org.uk Subject: Re: MTD EEPROM support and driver integration X-SA-Exim-Version: 4.2.1 (built Mon, 26 Dec 2011 16:57:07 +0000) X-SA-Exim-Scanned: Yes (on cassiel.sirena.org.uk) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3142 Lines: 69 --3aDtFGIaURYlkDgg Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Mon, Jul 08, 2013 at 10:25:38PM +0200, Maxime Ripard wrote: > On Mon, Jul 08, 2013 at 09:34:26AM +0100, Mark Brown wrote: > > I'd really like to see more discussion of this "DT parsing code for > > regmap" idea... I've missed almost all the context here. > The context was that I found we lack a way to simply express the need > for one driver to get a value from an EEPROM-like device, for example to > get a MAC Address, or a serial number, in a generic way, without having > to poke directly with some custom function that would be exported by the > EEPROM driver. This sort of information is often stored in places like flash partitions too. Are we sure that regmap is a good place to be hooking in here? The use case is sane, and being able to use regmap to do some of it seems sensible (I've seen people use OTP in PMICs for similar purposes) but perhaps an additional layer of abstraction on top makes sense. > What we've been discussing so far is that: > - To have a common framework we could base our work on, we could move > the EEPROM drivers from drivers/misc/eeprom to MTD > - To declare the ranges that needed to be used by a driver that was > needing a value from one of those MTD drivers, we would use regmap > with a MTD backend > - And since we actually need to declare which ranges and in which > device one driver would have to retrieve this value from, we were > actually in need of DT bindings. > This is pretty much the only context involved, and we are at the early > stage of the discussion, so any comment is very welcome :) If this stuff is being represented in MTD doesn't MTD already have adequate abstractions for saying "this region in flash". But otherwise this seems fine, it's not a generic regmap DT binding but instead rather more specific than that. --3aDtFGIaURYlkDgg Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.20 (GNU/Linux) iQIcBAEBAgAGBQJR3CRLAAoJELSic+t+oim9/fkQAIfgoN5SRhyj8ZAbGa4b4Ulm JzOoeIMuSKHxri5+dpG4mpCtORIrDq+dThd+c6plhBVBLZlJ2UoCT7NatfGB6jqM PFmZQ43nOZVcWwR291arCyG8b6gpd2c1AzrO3Ofufw0dlm3GgPKs4EuEZszPunoy Mkad+y8z0iGOvHEzXm0fAs4zC5tjHEVkgLToHxogZ6McF9OrIMrLey2BeUwvQJIY GQppcVJagLrRAROKECWfmdjlJSmkr3QqyZMMG/uaQovSVuJOPyDOBysE5i8XsBWY 7nnH14YXykmw6oUzH45E9ZBpI0R51VVhvMIdvIJMxqsclTd6M1y2JJxJV8AxhnJt odb7sMGEbEV2yUO7sSBFPLoAuPrT8GIO5IvNuJE0JP9b04O2Dvq/NDl8puhVw5Jo o+k3+y5WI3+PJDVrxKlp+w7Vuu6C0EOomQHYaEq8xhhkwwehIdtUMHXiPPU06ztm vXfzCVWWbaiEDHXX14tGP4Y+s14+3Tv/R6X+1+uyCyDflCJ+gIDq87uLLB9wnfpL V02xc/brP8Hu+cnedVgnzPx4NlzqHDhgNFifwpejx72zBJHDtW4w3TrxjaPvLw5a WVirvW65t8rHgxgA4Nw+p3ven3rEKfkW7Cn9mMVnJycFcrDO/NunI71tu1Oxr18A Q9Xq6ZRpziwfbvLdqhBj =OEHm -----END PGP SIGNATURE----- --3aDtFGIaURYlkDgg-- -- 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/