From mboxrd@z Thu Jan 1 00:00:00 1970 From: Takashi Iwai Subject: Re: External PCM plugin SDK Date: Thu, 10 Feb 2005 12:51:05 +0100 Message-ID: References: <1107958458.13863.43.camel@pegasus> <1107959869.13863.62.camel@pegasus> <1107970036.13863.77.camel@pegasus> <1107971323.13863.90.camel@pegasus> Mime-Version: 1.0 (generated by SEMI 1.14.5 - "Awara-Onsen") Content-Type: text/plain; charset=US-ASCII In-Reply-To: <1107971323.13863.90.camel@pegasus> 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: Marcel Holtmann Cc: alsa-devel@lists.sourceforge.net List-Id: alsa-devel@alsa-project.org At Wed, 09 Feb 2005 18:48:43 +0100, Marcel Holtmann wrote: > > Hi Takashi, > > > > and I need full duplex IO and volume control inside the same plugin for > > > the headset/handsfree support. > > > > Hmm, the share of volume control stuff between PCM and control plugins > > might be a bit tough. > > the problem is that the headsets can report back volume changes. We will > see this for the high quality headphones also some day, because the > audio and video remote stuff for Bluetooth is already specified. > > I will start without reacting to the volume control. We will see how > this works out. If so, running a daemon might be possibly easier than doing concurrent access? > > > > You don't have to set them if the hardware has no restriction. > > > > Usually, the period size defines the interrupt period. In the case of > > > > user-space driver, it corresponds to the expected poll period, etc. > > > > > > I can skip IOPLUG_HW_PERIOD_BYTES and IOPLUG_HW_PERIODS, but I must set > > > IOPLUG_HW_BUFFER_BYTES, because otherwise it segfaults even with aplay. > > > > OK, then use snd_pcm_ioplug_set_param_minmax() with some sane values. > > Leaving IOPLUG_HW_BUFFERS_BYTES out and only setting the period stuff > makes it working with the XMMS from CVS. Good to hear :) > Problem now is that XMMS closes the device and re-opens it when changing > the track and even when switching to its next track. This is problematic > when using Bluetooth, because I need to keep the underlaying connection > alive. Any idea? Yeah, that's bad behavior of xmms. I'll try a hack later... 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://ads.osdn.com/?ad_id=6595&alloc_id=14396&op=click