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 CCEB367B31 for ; Tue, 12 Apr 2005 10:05:58 +1000 (EST) From: Benjamin Herrenschmidt To: Johannes Berg In-Reply-To: <425A92B1.6080907@sipsolutions.net> References: <1113113792.9517.476.camel@gaston> <425A92B1.6080907@sipsolutions.net> Content-Type: text/plain Date: Tue, 12 Apr 2005 10:04:50 +1000 Message-Id: <1113264290.5388.16.camel@gaston> Mime-Version: 1.0 Cc: Takashi Iwai , linuxppc-dev list , "debian-powerpc@lists.debian.org" Subject: Re: [PATCH] pmac: sound support for latest laptops List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Mon, 2005-04-11 at 17:07 +0200, Johannes Berg wrote: > Hi, > > >This patch hacks the current Alsa snd-powermac driver to add support for > >recent machine models with the tas3004 chip, that is basically new > >laptop models. The Mac Mini is _NOT_ yet supported by this patch (soon > >soon ...). The G5s (iMac or Desktop) will need the rewritten sound > >driver on which I'm working on (I _might_ get a hack for analog only on > >some G5s on the current driver, but no promise). > > > > > That's cool. I do have one slight problem with it though: When I turn > down the Master mixer and up PCM it sounds badly overmodulated. I can > keep PCM at about 75% and turn up master, and all is fine. Would it make > sense to limit the PCM mixer to about 75% of its current limits, or how > does that actually work in the hardware? Well, the driver will let you do the setting you want, even if it's wrong :) You should indeed keep PCM at about 75% and use the master. There is also an issue with bad quality speakers used by Apple. OS X has a built-in software DSP that does equalisation & filtering in the kernel driver, and they have specific settings for it for various machine model speakers. Obviously, we don't have such thing. Ben.