From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stephen Warren Subject: Re: [PATCH 2/3] ASoC: generic simple sound card DT bindings Date: Wed, 04 Sep 2013 12:21:36 -0600 Message-ID: <52277A30.8010102@wwwdotorg.org> References: <1377945878-13322-1-git-send-email-mpa@pengutronix.de> <1377945878-13322-3-git-send-email-mpa@pengutronix.de> <52220766.1040504@metafoo.de> <52263795.8010600@wwwdotorg.org> <20130903231922.GL3084@sirena.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20130903231922.GL3084@sirena.org.uk> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: alsa-devel-bounces@alsa-project.org Sender: alsa-devel-bounces@alsa-project.org To: Mark Brown Cc: devicetree@vger.kernel.org, alsa-devel@alsa-project.org, Lars-Peter Clausen , Liam Girdwood , Grant Likely , Sascha Hauer , Markus Pargmann , Shawn Guo , linux-arm-kernel@lists.infradead.org List-Id: devicetree@vger.kernel.org On 09/03/2013 05:19 PM, Mark Brown wrote: > On Tue, Sep 03, 2013 at 01:25:09PM -0600, Stephen Warren wrote: > >> Mark has made the argument that (at least for CODEC analog pins) >> we can simply put those strings into the binding document, and >> make them as much a part of the binding as anything else. After >> all, (at least for CODEC analog pins) the values are simply the >> names of the pins on the package, as listed by the HW >> documentation itself. > >> We could presumably do the same thing for DAIs; in DT, use a >> string-based DAI name derived directly from the HW documentation, >> rather than the current intra-ASoC DAI name strings. > >> That said, I will admit that I personally don't really like the >> idea of using strings in bindings. That opinion certainly isn't >> universal though. > > I think either works - with DAIs there is a tendency (though not > universal) for devices to just have numbered interfaces which makes > the numbers more natural. I'm more concerned with the binding > being legible than with what ends up physically written in there, > the original reason for strings (apart from the fact that they're > in the drivers already) was that there was a lot of resistance in > the DT community to symbolic constants. That would have lead to > bindings which looked like line noise. True. >>> The binding also assumes that a CPU controller may have one DAI >>> at most. In my opinion this binding ought to use the upcoming >>> of_xlate stuff for ASoC components. > >> That restriction seems reasonable for a *simple* DT sound >> binding. For more complex cards, one could presumably create more >> complex bindings, be they generic bindings that cover arbitrary >> more complex cases, or bindings for specific configurations that >> happen to include multiple DAIs. > > The complexity there comes from the device that's being used rather > than the design of the sound card though - the fact that a SoC has > an audio block with many DAIs shouldn't prevent it using the simple > bindings if someone just hung a simple CODEC off one of the DAIs. Yes, exactly.