From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from gate.crashing.org (gate.crashing.org [63.228.1.57]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTP id 1D358679F7 for ; Fri, 24 Mar 2006 08:09:17 +1100 (EST) Subject: Re: new sound driver From: Benjamin Herrenschmidt To: Johannes Berg In-Reply-To: <1143134017.8395.19.camel@localhost> References: <1143020119.11724.41.camel@localhost> <1143064237.3823.29.camel@localhost.localdomain> <1143134017.8395.19.camel@localhost> Content-Type: text/plain Date: Fri, 24 Mar 2006 08:09:05 +1100 Message-Id: <1143148145.4257.8.camel@localhost.localdomain> Mime-Version: 1.0 Cc: linuxppc-dev@ozlabs.org, Alastair Poole List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , > What I'm currently thinking of is creating one PCM per codec, and then > if you can't use them at the same time just forbid access to it. No, it should really be one PCM per bus... I don't see why you would prevent somebody from outputing on both digital and analog outputs at the same time for example (the same data of course). One PCM = one stream = one bus carrying the samples. All codecs on that bus whould be set to the same settings of course. If one can't but the other can, just mute the one that can't I suppose... Also, Alsa does have some means of asynchronous notifyication of a state change on a control (and calls you back later with some locking) though I'm not too familiar with the details. You should ask on the list once you have the basic dbdma stuff there :) > > Just sleep on it for now :) We definitely need a "core" module that > > handles all of the gpio mess. .. > > Yeah. Haven't even opened that can of worms yet... > > johannes