From mboxrd@z Thu Jan 1 00:00:00 1970 From: Clemens Ladisch Subject: Re: question on hardware mixing Date: Tue, 09 Dec 2008 09:52:51 +0100 Message-ID: <493E31E3.2080504@ladisch.de> References: <20081205165341.GA21294@rakim.wolfsonmicro.main> <1228496062-21379-1-git-send-email-broonie@opensource.wolfsonmicro.com> <98769532B4BB14429434178695419EAE26861315@bgsmsx501.gar.corp.intel.com> <75b66ecd0812052058r36ed20fdo3dc6e40ac23339bf@mail.gmail.com> <98769532B4BB14429434178695419EAE268614A1@bgsmsx501.gar.corp.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from out2.smtp.messagingengine.com (out2.smtp.messagingengine.com [66.111.4.26]) by alsa0.perex.cz (Postfix) with ESMTP id 3B44D1037F4 for ; Tue, 9 Dec 2008 09:52:56 +0100 (CET) In-Reply-To: <98769532B4BB14429434178695419EAE268614A1@bgsmsx501.gar.corp.intel.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: "Harsha, Priya" Cc: "alsa-devel@alsa-project.org" , Lee Revell List-Id: alsa-devel@alsa-project.org Harsha, Priya wrote: > In the trigger function - I see that from substream->runtime->private_data, > voice specific parameters are extracted. How and can somehow user space > fill in some private data to the driver so that driver can process voice > in a different way and music in a different way? On the Emu10k1 chip, the hardware voices are used for both PCM playback and wavetable (MIDI) playback. Voice-specific parameters are set for MIDI data; the parameters come from the soundfont that was loaded to specify how the instruments sound. (Here, the term "voice" has no relation to the sound of a human voice.) As far as PCM playback is concerned, ALSA does not have any predefined mechanism to differentiate between voice and music audio streams. It would be possible to define mixer controls to switch between these settings for each substream. HTH Clemens