From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mark Brown Subject: Re: [PATCH 4/7] Alchemy: DB1200 AC97+I2S audio support. Date: Mon, 8 Jun 2009 13:44:11 +0100 Message-ID: <20090608124411.GA3396@rakim.wolfsonmicro.main> References: <1244399944-29043-2-git-send-email-manuel.lauss@gmail.com> <1244399944-29043-3-git-send-email-manuel.lauss@gmail.com> <1244399944-29043-4-git-send-email-manuel.lauss@gmail.com> <1244399944-29043-5-git-send-email-manuel.lauss@gmail.com> <20090608092521.GA7858@sirena.org.uk> <20090608102018.GA6547@rakim.wolfsonmicro.main> <20090608115336.GA25827@rakim.wolfsonmicro.main> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from opensource2.wolfsonmicro.com (opensource.wolfsonmicro.com [80.75.67.52]) by alsa0.perex.cz (Postfix) with ESMTP id 9328E243B8 for ; Mon, 8 Jun 2009 14:44:12 +0200 (CEST) Content-Disposition: inline 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: Manuel Lauss Cc: Linux-MIPS , alsa-devel@alsa-project.org, Ralf Baechle , Manuel Lauss List-Id: alsa-devel@alsa-project.org On Mon, Jun 08, 2009 at 02:21:18PM +0200, Manuel Lauss wrote: > I see now what you mean, but this is ugly as sin: > I now need to register 2 platform devices in the board code: 1 for the DAI > (with resources mmio + irq) and 1 for the DMA engine (with ddma id resources), > or register the DMA engine device from within the AC97/I2S drivers. > This is in my opinion even worse than the current scheme, which at least allows > me to group all PSC resources into one struct resource which all audio-related > drivers can share without too much uglyness. If you trigger registration the DMA engine from within the I2S and AC97 devices you can still group everything together like you want to so I don't really see the problem - they're peering at a different device for the data but other than that things are unchanged. At the minute you're loosing a lot of sharing by having this in the individual machine drivers. Note that one of the possibilities once multiple sound card support is introduced is that DAIs could be shared between multiple cards. This is only going to be at all useful for CPU DAIs which allow separate configuration of the RX and TX paths and will never be the common case but it's something to bear in mind. From mboxrd@z Thu Jan 1 00:00:00 1970 Received: with ECARTIS (v1.0.0; list linux-mips); Mon, 08 Jun 2009 13:44:24 +0100 (WEST) Received: from opensource.wolfsonmicro.com ([80.75.67.52]:40849 "EHLO opensource2.wolfsonmicro.com" rhost-flags-OK-OK-OK-FAIL) by ftp.linux-mips.org with ESMTP id S20022690AbZFHMoR (ORCPT ); Mon, 8 Jun 2009 13:44:17 +0100 Received: from rakim.wolfsonmicro.main (lumison.wolfsonmicro.com [87.246.78.27]) by opensource2.wolfsonmicro.com (Postfix) with ESMTPSA id E3D69110024; Mon, 8 Jun 2009 13:44:11 +0100 (BST) Received: from broonie by rakim.wolfsonmicro.main with local (Exim 4.69) (envelope-from ) id 1MDeCx-0000vh-ER; Mon, 08 Jun 2009 13:44:11 +0100 Date: Mon, 8 Jun 2009 13:44:11 +0100 From: Mark Brown To: Manuel Lauss Cc: Linux-MIPS , Ralf Baechle , Manuel Lauss , alsa-devel@alsa-project.org Subject: Re: [alsa-devel] [PATCH 4/7] Alchemy: DB1200 AC97+I2S audio support. Message-ID: <20090608124411.GA3396@rakim.wolfsonmicro.main> References: <1244399944-29043-2-git-send-email-manuel.lauss@gmail.com> <1244399944-29043-3-git-send-email-manuel.lauss@gmail.com> <1244399944-29043-4-git-send-email-manuel.lauss@gmail.com> <1244399944-29043-5-git-send-email-manuel.lauss@gmail.com> <20090608092521.GA7858@sirena.org.uk> <20090608102018.GA6547@rakim.wolfsonmicro.main> <20090608115336.GA25827@rakim.wolfsonmicro.main> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Cookie: You too can wear a nose mitten. User-Agent: Mutt/1.5.19 (2009-01-05) Return-Path: X-Envelope-To: <"|/home/ecartis/ecartis -s linux-mips"> (uid 0) X-Orcpt: rfc822;linux-mips@linux-mips.org Original-Recipient: rfc822;linux-mips@linux-mips.org X-archive-position: 23333 X-ecartis-version: Ecartis v1.0.0 Sender: linux-mips-bounce@linux-mips.org Errors-to: linux-mips-bounce@linux-mips.org X-original-sender: broonie@opensource.wolfsonmicro.com Precedence: bulk X-list: linux-mips On Mon, Jun 08, 2009 at 02:21:18PM +0200, Manuel Lauss wrote: > I see now what you mean, but this is ugly as sin: > I now need to register 2 platform devices in the board code: 1 for the DAI > (with resources mmio + irq) and 1 for the DMA engine (with ddma id resources), > or register the DMA engine device from within the AC97/I2S drivers. > This is in my opinion even worse than the current scheme, which at least allows > me to group all PSC resources into one struct resource which all audio-related > drivers can share without too much uglyness. If you trigger registration the DMA engine from within the I2S and AC97 devices you can still group everything together like you want to so I don't really see the problem - they're peering at a different device for the data but other than that things are unchanged. At the minute you're loosing a lot of sharing by having this in the individual machine drivers. Note that one of the possibilities once multiple sound card support is introduced is that DAIs could be shared between multiple cards. This is only going to be at all useful for CPU DAIs which allow separate configuration of the RX and TX paths and will never be the common case but it's something to bear in mind.