From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mark Brown Subject: Re: [PATCH] ASoC: s3c24xx platform: Fix s3c2410_dma_started called at wrong time Date: Thu, 20 Aug 2009 19:47:14 +0100 Message-ID: <20090820184714.GD5032@sirena.org.uk> References: <1250761331.4412.70.camel@shinel> <20090820101549.GA23141@rakim.wolfsonmicro.main> <1250769588.3684.28.camel@sl> <20090820121851.GB11699@sirena.org.uk> <1250775480.1404.19.camel@sl> <20090820145207.GA25143@rakim.wolfsonmicro.main> <1250783107.1404.70.camel@sl> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from cassiel.sirena.org.uk (cassiel.sirena.org.uk [80.68.93.111]) by alsa0.perex.cz (Postfix) with ESMTP id 28282103886 for ; Thu, 20 Aug 2009 21:06:35 +0200 (CEST) Content-Disposition: inline In-Reply-To: <1250783107.1404.70.camel@sl> 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: Shine Liu Cc: ben@simtec.co.uk, alsa-devel@alsa-project.org List-Id: alsa-devel@alsa-project.org On Thu, Aug 20, 2009 at 11:45:07PM +0800, Shine Liu wrote: > > The callback doesn't need to be set up within the trigger function - if > > it's done before the trigger functions are called then the DMA trigger > > can call it. Off the top of my head I'd expect it's possible to set it > > up when the device is opened. > Who call the DMA trigger? When? In any of the platform/cpu_dai trigger > functions? It's called ultimately by user space; within ASoC it's always called by the core trigger function in the fixed order that it has. The open() callback would be a safe place to do the setup - that's called before anything else.