From mboxrd@z Thu Jan 1 00:00:00 1970 From: Peter Ujfalusi Subject: Re: [RFC v2 0/3] ASoC: Option to reorder widget power sequence Date: Tue, 7 Dec 2010 11:29:15 +0200 Message-ID: <201012071129.15475.peter.ujfalusi@nokia.com> References: <1291383073-16048-1-git-send-email-peter.ujfalusi@nokia.com> <20101206224008.GA2862@opensource.wolfsonmicro.com> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Return-path: Received: from mgw-sa01.nokia.com (smtp.nokia.com [147.243.1.47]) by alsa0.perex.cz (Postfix) with ESMTP id 9F019103842 for ; Tue, 7 Dec 2010 10:29:16 +0100 (CET) In-Reply-To: <20101206224008.GA2862@opensource.wolfsonmicro.com> 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: ext Mark Brown Cc: "alsa-devel@alsa-project.org" , Liam Girdwood List-Id: alsa-devel@alsa-project.org On Tuesday 07 December 2010 00:40:08 ext Mark Brown wrote: > On Fri, Dec 03, 2010 at 03:31:10PM +0200, Peter Ujfalusi wrote: > > Quite some time ago I have faced similar issue with the sequence of the > > DAPM register writes [1] > > For that issue, I used a workaround within the twl4030 codec driver. > > Now I have again issue with the register write sequence. > = > Sorry I've not got back to you yet - I want to implement the thing I was > talking about with inserting the register update into the DAPM sequence. > I think that is going to be easier and more generally useful, and it > doesn't rely on drivers knowing what's going on with the DAPM sequncing > code which is much cleaner from an abstraction point of view. Fair enough. I did taken a look at the possibility to do the register update between DAP= M = power down and up, but I thought it is a bit big change (the place, where t= he = DAPM power down and up happens is quite deep, and I was not sure how to inj= ect = things between those). I'm no longer sure, when the register update should happen. It might be worth doing the update at around the power enable for the widge= t. IN that way at least we are going to filter the power updates before the = switch: DAC -> PGA1 -> widget -> switch -> PGA2 -> out If we update the register for the switch before the DAPM power up, than we = can = expose the switching from DAC, PGA1, widget. If we do the update at the same time (or around), when the power for the = switch would have been enabled, than we are filtering the switching for the = DAPM widgets before the switch. -- = P=E9ter