From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Alexander E. Patrakov" Subject: Re: [alsa-devel] [PATCH 1/3] sound: Add a quirk to enforce period_bytes Date: Mon, 16 Jun 2014 20:38:52 +0600 Message-ID: <539F017C.90408@gmail.com> References: <1402762571-6316-1-git-send-email-m.chehab@samsung.com> <1402762571-6316-2-git-send-email-m.chehab@samsung.com> <539E9F25.7030504@ladisch.de> <20140616112110.3f509262.m.chehab@samsung.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20140616112110.3f509262.m.chehab@samsung.com> Sender: linux-media-owner@vger.kernel.org To: Mauro Carvalho Chehab , Clemens Ladisch Cc: Takashi Iwai , alsa-devel@alsa-project.org, Mauro Carvalho Chehab , Linux Media Mailing List List-Id: alsa-devel@alsa-project.org 16.06.2014 20:21, Mauro Carvalho Chehab wrote: > Both xawtv and tvtime use the same code for audio: > http://git.linuxtv.org/cgit.cgi/xawtv3.git/tree/common/alsa_stream.c > > There's an algorithm there that gets the period size form both the > capture and the playback cards, trying to find a minimum period that > would work properly for both. I don't see any adaptive resampler (similar to what module-loopback does in pulseaudio) there. Without that, or dynamically controlling the audio capture clock PLL in the tuner, xruns are unavoidable when transferring data between two unrelated cards. So, until any further evidence appears, I think it is a common bug in these audio codes. -- Alexander E. Patrakov