From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel Mack Subject: Re: Hello Date: Thu, 12 Sep 2013 19:33:05 +0200 Message-ID: <5231FAD1.5070608@gmail.com> References: <20130911231224.2d52a2e3@mach1> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mail-bk0-f51.google.com (mail-bk0-f51.google.com [209.85.214.51]) by alsa0.perex.cz (Postfix) with ESMTP id 89BFD2654D0 for ; Thu, 12 Sep 2013 19:33:07 +0200 (CEST) Received: by mail-bk0-f51.google.com with SMTP id mx10so49341bkb.10 for ; Thu, 12 Sep 2013 10:33:07 -0700 (PDT) In-Reply-To: <20130911231224.2d52a2e3@mach1> 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: Michael Jordan Cc: alsa-devel@alsa-project.org, "Hebbar, Gururaja" List-Id: alsa-devel@alsa-project.org On 12.09.2013 05:12, Michael Jordan wrote: > If I am trying to ask some questions about the alsa system, do I need > to copy somebody directly to get a response? I have posted about 4 > questions on the group in the last few months, and I have not even > gotten a slap on the hand. > > The reason I am contacting you is you have mentioned working on the > TLV320AIC3X which is the chip used on the OMAPL138 board that we have. > I am attempting to write a driver for a PCM3168A which we have already > constructed a board for, and plugs into the 100 pin audio expander > connecter. I have the basic draft of a driver, but everything in the > code seems to be fairly strongly coded for the DA850 boards to use the > TLV320AIC. I can prevent it loading, and my module will load, but > things are not "connecting" internally. I assumed that I would need to > make some changes in the arch/arm/mach-davinci/board-da850-evm.c. In general, you shouldn't have any audio specific code in arch/arm/mach-davinci/*. > However what I am running into is chasing me up a trail that eventually > has me modifying mach-types.h and creating a whole new board > configuration. I said ok, so I copied board-da850-evm.c to > board-da850-evm-mod.c which made it necessary for me to begin modifying > some Kconfig's, etc., and I still cannot get the kernel to compile with > the new kernel driver. > > I just need to know, am I heading down the wrong path with this? I have > a pcm3168a.c and pcm3168a.h which have a basic structure for the new > codec, For reviews, please post patches against the current mainline linux git tree to this list. > but I cannot figure out how to get the system to actually use it > because it basically appears that the TLV320AIC3X is "hard-wired" into > the system. Consider the following basics: - board files in arch/arm/ should only contain basic machine-specific hardware setup (including i2c/spi device matching) - in ALSA, things are structured in machine, platform and codec parts, which are separated from each other in order to make them system and platform generic. Make sure to read Documentation/sound/alsa/soc/* for this. Also note that traditional board files are going away. If you want your platform to be future-proof, start using device-tree files to describe your board. As a starting point, have a look at arch/arm/boot/dts/da850-evm.dts in the current mainline kernel git. With the upcoming simple-card DT support, you might even be able to avoid writing an ASoC maschine driver altogether. Daniel