From mboxrd@z Thu Jan 1 00:00:00 1970 From: Takashi Iwai Subject: Re: [RFE] Power down AC'97 when muted Date: Thu, 23 Dec 2004 16:10:20 +0100 Message-ID: References: <41C9CDE3.4020605@drzeus.cx> Mime-Version: 1.0 (generated by SEMI 1.14.5 - "Awara-Onsen") Content-Type: text/plain; charset=US-ASCII Return-path: In-Reply-To: <41C9CDE3.4020605@drzeus.cx> Sender: alsa-devel-admin@lists.sourceforge.net Errors-To: alsa-devel-admin@lists.sourceforge.net List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , List-Archive: To: Pierre Ossman Cc: alsa-devel@lists.sourceforge.net List-Id: alsa-devel@alsa-project.org At Wed, 22 Dec 2004 20:41:23 +0100, Pierre Ossman wrote: > > I have a request for a new feature in the AC97 driver (my card is an > intel ICH4). I'd like to see the driver power off the AC97 part when the > master volume is muted. Currently the power control has a seperate > volume control that can be used. > > The reason I want this is because my laptop has a LED indicating mute > status. This is triggered by the power down function of the AC97 function. > > Since the power is exposed through a volume control this could be done > in user space, but that would me that every program that mutes the sound > card would need special logic to see if the card has an "External > amplifier" (as the channel is called). Therefore it seems much better to > do this in the driver. > > Another point is that Windows seems to have this behaviour (since the > LED functions fine there in every application) so manufacturers rely on > this (HP in my case). > > I tried doing this myself by adding an extra call inside > ac97_put_double() checking for changes to the master channel but I > couldn't get it to work. I just got a faint flicker out of the LED. If > people give me enough pointers I might be able to put together a patch > for this. It's BUG #667, right? https://bugtrack.alsa-project.org/alsa-bug/view.php?id=667 I uploaded a test patch there. Please give it a try. Takashi ------------------------------------------------------- SF email is sponsored by - The IT Product Guide Read honest & candid reviews on hundreds of IT Products from real users. Discover which products truly live up to the hype. Start reading now. http://productguide.itmanagersjournal.com/