From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1426130AbdEZLGZ (ORCPT ); Fri, 26 May 2017 07:06:25 -0400 Received: from mezzanine.sirena.org.uk ([106.187.55.193]:36132 "EHLO mezzanine.sirena.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753457AbdEZLGU (ORCPT ); Fri, 26 May 2017 07:06:20 -0400 Date: Fri, 26 May 2017 12:06:02 +0100 From: Mark Brown To: Evgeniy Polyakov Cc: "Alex A. Mihaylov" , Greg Kroah-Hartman , Sebastian Reichel , "linux-kernel@vger.kernel.org" , "linux-pm@vger.kernel.org" Message-ID: <20170526110602.jtvxf76abks4v3xf@sirena.org.uk> References: <20170525174639.3191-1-minimumlaw@rambler.ru> <20170525174639.3191-2-minimumlaw@rambler.ru> <404871495743279@web24o.yandex.ru> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="zb4eob3qhd77w2li" Content-Disposition: inline In-Reply-To: <404871495743279@web24o.yandex.ru> X-Cookie: Smear the road with a runner!! User-Agent: NeoMutt/20170306 (1.8.0) X-SA-Exim-Connect-IP: 2001:470:1f1d:6b5::3 X-SA-Exim-Mail-From: broonie@sirena.org.uk Subject: Re: [PATCH 1/4] Introduce regmap infrastructure over Maxim/Dalas OneWire (W1) bus X-SA-Exim-Version: 4.2.1 (built Mon, 26 Dec 2011 16:24:06 +0000) X-SA-Exim-Scanned: No (on mezzanine.sirena.org.uk); Unknown failure Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --zb4eob3qhd77w2li Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Thu, May 25, 2017 at 11:14:39PM +0300, Evgeniy Polyakov wrote: > Frankly saying, your non-regmap version was so much simpler, smaller and cleaner. > I wonder why did people force you to use regmap. > Guys, please speak up, if you want driver authors to use THIS, it is really flawed. > Sebastien, iirc it was your idea to use regmaps, what was the reason for this? So, this is the first I've seen of this series but in general the main reason for using regmap is that it allows best practice to be factored out into common code both in terms of the I/O itself and also in terms of framework code being able to provide regmap based helpers for common operations so drivers need less code. The cache code is also really useful for a lot of devices, it's a performance boost for reads and is well optimized for restoring device state if you don't care about sequencing (this is where some of the MMIO users come from). You also get a bunch of debug support for free, things like the tracepoints and debugfs files (those do work better if you describe the register map). Looking at the code in the regmap patch I have to say I'm very surprised if this is adding much complexity, usually moving to regmap is basically a sed. --zb4eob3qhd77w2li Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAABCAAdFiEEreZoqmdXGLWf4p/qJNaLcl1Uh9AFAlkoDBkACgkQJNaLcl1U h9Acogf9Fa8zCh00TCsT+nLIpvX7xNlE0+QZrszLg5vmWNA8DK6TV5OQJoU84bzj +4fPME7LbuZ6quWZEjjjd8/DUml+mKE9J+iVNlscqZm8M2GoRHZjpzQEaoZLWAxS czB0kriwlxDDNcOpH7Kw4mKFeEFOGw8FmBgcgDq94DUVVQ2nW/+dTO/O2fIe8bIC qRSAZT4YqZkGBJ+th0/KRIJrC7UPKgRdMH18g5Xftzq4kzXdLvkE+jB0PNgiE2ki UGO5FS3B+0/J0cKaiP6nCyAYpL8NfWjFLhh4cRA+11m0KCXLFjUTkCR4gw+jP+5Y Fh86ELLPsc2UPOg0Zz6ly7OXQfIiRg== =Hc+E -----END PGP SIGNATURE----- --zb4eob3qhd77w2li--