From mboxrd@z Thu Jan 1 00:00:00 1970 From: Clemens Ladisch Subject: Re: Buffer underrun in a not empty playback buffer Date: Wed, 25 Jul 2012 12:41:34 +0200 Message-ID: <500FCD5E.4070401@ladisch.de> References: <500F9321.30305@voiceinterconnect.de> <500F99B9.1050905@ladisch.de> <500FC6B7.1040309@voiceinterconnect.de> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Return-path: Received: from out3-smtp.messagingengine.com (out3-smtp.messagingengine.com [66.111.4.27]) by alsa0.perex.cz (Postfix) with ESMTP id DA8812652DF for ; Wed, 25 Jul 2012 12:41:35 +0200 (CEST) In-Reply-To: <500FC6B7.1040309@voiceinterconnect.de> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: alsa-devel-bounces@alsa-project.org Sender: alsa-devel-bounces@alsa-project.org To: Christian Gruber Cc: alsa-devel@alsa-project.org List-Id: alsa-devel@alsa-project.org Christian Gruber wrote: > Am 25.07.2012 09:01, schrieb Clemens Ladisch: >> (Or does that driver, which you did not name, do additional checks?) > > The mentioned driver is an ALSA-driver, which was originally developed > by Texas Instruments for their Audio-Codec family TLV320AIC3x, but was > adapted to a specific customer board. The TLV320AIC3x are I=B2S codecs. DMA and buffering are done by the controller, which is managed by the platform driver. > But the behaviour of the mentioned driver is, that an underrun occurs, > even when there are lots of periods (> 6 periods) inside the playback > buffer. And this is not correct, isn't it? This is indeed not correct (if there isn't much time between reading the buffer fill level and the underrun). It's likely that the platform driver does not report the buffer position correctly. Regards, Clemens