From mboxrd@z Thu Jan 1 00:00:00 1970 From: Adrian McMenamin Subject: Re: static snd_pcm_uframes_t snd_aicapcm_pcm_pointer(snd_pcm_substream_t *substream) Date: Sun, 26 Feb 2006 10:55:05 +0000 Message-ID: <1140951305.9540.3.camel@localhost.localdomain> References: <1140813688.9827.1.camel@localhost.localdomain> <1140918491.24141.80.camel@mindpipe> Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1140918491.24141.80.camel@mindpipe> 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: Lee Revell Cc: alsa-devel@lists.sourceforge.net List-Id: alsa-devel@alsa-project.org On Sat, 2006-02-25 at 20:48 -0500, Lee Revell wrote: > On Fri, 2006-02-24 at 20:41 +0000, Adrian McMenamin wrote: > > What should my pointer callback return - is it the number of frames > > still to come from the dma transfer or the number of frames still to > > play in the device's buffer, or something else? > > > > http://www.alsa-project.org/~iwai/writing-an-alsa-driver/x639.htm#PCM-INTERFACE-OPERATORS-POINTER-CALLBACK The problem with that - which I have read many times and even host locally - http://newgolddream.dyndns.info/alsa - so I have a copy that is very easily accessible is that: "This callback is called when the PCM middle layer inquires the current hardware position on the buffer." Could mean any number of different things because there is more than one buffer here. As it is James Courtier-Dutton has clarified this for me. But one more question: what is the different between this and the interrupt handling? Are they both seeking to do the same thing? ------------------------------------------------------- This SF.Net email is sponsored by xPML, a groundbreaking scripting language that extends applications into web and mobile media. Attend the live webcast and join the prime developer group breaking into this new coding territory! http://sel.as-us.falkag.net/sel?cmd=lnk&kid=110944&bid=241720&dat=121642