From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755120AbcASOLz (ORCPT ); Tue, 19 Jan 2016 09:11:55 -0500 Received: from mail-lf0-f65.google.com ([209.85.215.65]:33192 "EHLO mail-lf0-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753670AbcASOLq (ORCPT ); Tue, 19 Jan 2016 09:11:46 -0500 Date: Tue, 19 Jan 2016 15:11:44 +0100 From: Johan Hovold To: Mark Brown Cc: Johan Hovold , Michael Trimarchi , Jacob Siverskog , Jaroslav Kysela , Takashi Iwai , Liam Girdwood , "alsa-devel@alsa-project.org" , LKML Subject: Re: [PATCH 2/3] ASoC: pcm179x: Add I2C interface driver Message-ID: <20160119141144.GB12069@localhost> References: <1453132657-18678-1-git-send-email-jacob@teenage.engineering> <1453132657-18678-3-git-send-email-jacob@teenage.engineering> <20160118165657.GE3169@localhost> <20160119122524.GM6588@sirena.org.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20160119122524.GM6588@sirena.org.uk> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jan 19, 2016 at 12:25:24PM +0000, Mark Brown wrote: > On Mon, Jan 18, 2016 at 05:56:57PM +0100, Johan Hovold wrote: > > On Mon, Jan 18, 2016 at 05:14:42PM +0100, Michael Trimarchi wrote: > > > > > + { .compatible = "ti,pcm1792a", }, > > > > + { } > > > > +}; > > > > +MODULE_DEVICE_TABLE(of, pcm179x_of_match); > > > > can match go in the common part? > > > For matching purposes it could, but that would prevent the OF-aliases > > from being defined for the driver modules. > > > There are a couple of codec drivers that have taken this route, and it > > works as long as they also define a legacy (e.g. i2c_device_id) table > > that modalias autoloading can fall back to. > > > But having having the common module carry the OF-aliases does not seem > > like the right thing to do (e.g. as the common module cannot drive > > anything on its own) even if it avoids a copy of the OF id table. > > This does seem like something that the modules code should be able to > cope with - we have a reference from the driver struct to the table > which you'd really expect it to be using. We already have some issues > there with userspace not handling multiple modaliases terribly well IIRC. That reference is only used for matching, while the aliases are generated from the MODULE_DEVICE_TABLE macro (and elf magic). Even if this sometimes means duplicating an id-table (and i2c and spi OF id tables aren't necessarily always identical either), it seems to me that the MODULE_DEVICE_TABLE should go in the actual driver rather than any module dependency. Thanks, Johan