From mboxrd@z Thu Jan 1 00:00:00 1970 From: Robert Jarzmik Subject: Re: [PATCH 1/4] ASoC: wm9713: add binding for WM9713 codec Date: Fri, 26 Feb 2016 02:33:49 +0100 Message-ID: <87povkuuf6.fsf@belgarion.home> References: <1455979079-9030-1-git-send-email-robert.jarzmik@free.fr> <20160220171459.GA18327@sirena.org.uk> <871t87z1gz.fsf@belgarion.home> <20160220195925.GF18327@sirena.org.uk> <87twl3xgud.fsf@belgarion.home> <20160220211659.GG18327@sirena.org.uk> <878u2fxbp9.fsf@belgarion.home> <20160221014920.GK18327@sirena.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20160221014920.GK18327@sirena.org.uk> (Mark Brown's message of "Sun, 21 Feb 2016 10:49:20 +0900") 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, linux-kernel@vger.kernel.org, patches@opensource.wolfsonmicro.com, Liam Girdwood , Haojian Zhuang , Takashi Iwai , linux-arm-kernel@lists.infradead.org, Daniel Mack List-Id: devicetree@vger.kernel.org Mark Brown writes: >> > It will eumerate the AC'97 bus by itself and does not need the CODEC to >> > be described. > >> I think I still don't get it. > >> So let's rephrase it another way : how will the function wm9713_probe() be >> called, ie. what is the possible function backtrace leading to that call ? > > It will not be called, the generic AC'97 code will be used. Ok, if it's not called no code in sound/soc/codecs/wm9713.c will be used, right ? In that case wm9713_set_dai_clkdiv() will never be used, nor will the wm9713_audio_map or wm9713_dapm_widgets be created, which will break all userspace programs relying on these mixers and DAPM routes. Or am I missing something ? >> Do you have a devicetree example somewhere, with (ac97 host, audio codec) pair I >> can have a look at to understand ? > > Some Atmel boards do this IIRC, as does the AACI driver (via AMBA but > same effect). I suppose you mean sound/arm/aaci.c, which is more a platform_data like driver (if I understood the integrator code correctly). I suppose we can achieve comparable result with sound/arm/pxa2xx-ac97.c, but as to know if the functionality will be comparable to sound/soc/pxa/pxa2xx-ac97.c, it's hard to say. If I count the DMA requestors, I see 5 in the sound/soc version, and 2 in sound/arm. That makes me believe the sound/arm version is inferior. Cheers. -- Robert