From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Jander Subject: Re: ASoC MPC5xxx PSC AC97 audio driver Date: Thu, 8 Sep 2011 16:32:31 +0200 Message-ID: <20110908163231.4b721973@archvile> References: <20110908121600.267dee07@archvile> <20110908124529.520c1388@archvile> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from protonic.xs4all.nl (protonic.xs4all.nl [213.84.116.84]) by alsa0.perex.cz (Postfix) with ESMTP id 826D2103811 for ; Thu, 8 Sep 2011 16:32:23 +0200 (CEST) In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: alsa-devel-bounces@alsa-project.org Errors-To: alsa-devel-bounces@alsa-project.org To: "jonsmirl@gmail.com" Cc: Grant Likely , alsa-devel@alsa-project.org List-Id: alsa-devel@alsa-project.org Dear Jon, On Thu, 8 Sep 2011 06:55:56 -0400 "jonsmirl@gmail.com" wrote: > On Thu, Sep 8, 2011 at 6:45 AM, David Jander > wrote: > > > > Dear Jon, > > > > Thanks for replying so quickly. > > > > On Thu, 8 Sep 2011 06:28:02 -0400 > > "jonsmirl@gmail.com" wrote: > >> On Thu, Sep 8, 2011 at 6:16 AM, David Jander > >> wrote: > >> > > >> > Dear Jon, > >> > >> Here's the device tree... > >> http://git.digispeaker.com/?p=digispeaker-kernel.git;a=blob;f=arch/powerpc/boot/dts/dspeak01.dts;h=50cc247b4da0eb2bc4deb315b1b5348af87e5979;hb=9166a4a4141ab7c8d7a7b97fa5b726e11a8d0ca4 > > > > Thanks... but it uses I2S, not AC97 :-( > > It doesn't have a "fsl,mpc5200-pcm" node either, btw. > > In the case of I2C, this makes some sense, since the Codec is usually > > connected to two different interfaces at the same time (I2S and I2C for > > control), so you have 2 device nodes. AC97 OTOH has just one interface. It > > is connected to a AC97 bus (a PSC in this case). AFAICS there are no OF > > bindings yet for an AC97 bus, so the actual codec doesn't figure and thus > > still needs this ugly fabric driver thing. > > Try the pcm030 device tree... > > http://git.digispeaker.com/?p=digispeaker-kernel.git;a=blob;f=arch/powerpc/boot/dts/pcm030.dts;h=30bfdc04c6dfacd88a9c6e325e873d75a633bdf5;hb=HEAD I had also looked at that one.... still no "fsl,mpc5200-pcm" node. I would not expect one either, given the way the fabric driver works. But what is the reason for this OF compatible string then? Most important question: Does the mpc5200_dma.c/mpc5200_psc_ac97.c combination in current mainline still work correctly? I am unable (by inference) to say for sure that mpc5200_hpcd_probe() will always be called before psc_ac97_of_probe(). If it is not, the latter will OOPS. In fact, when I try to mimic the same on a MPC5121e, it does get called in the opposite order! My theory is that this order may have changed in recent versions of kernel/ALSA, and that since that moment this driver has been broken and nobody noticed yet. I need to know, because I intend to enhance mpc5200_psc_ac97.c, to also support MPC512x, but this is not working the way it is written now. If I knew for sure that mpc5200 still works this way, I would need to find a bug in my code. In the other case, I'd just go and fix the driver for MPC5200 also, but I have no hardware to try it out myself. Best regards, -- David Jander Protonic Holland.