From mboxrd@z Thu Jan 1 00:00:00 1970 From: Raymond Yau Subject: Re: [RFC PATCH 0/4] better support for bursty DMA usages Date: Wed, 22 Jul 2015 22:44:50 +0800 Message-ID: References: <1436350236-17509-1-git-send-email-pierre-louis.bossart@linux.intel.com> <55A6380E.4060605@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mail-oi0-f41.google.com (mail-oi0-f41.google.com [209.85.218.41]) by alsa0.perex.cz (Postfix) with ESMTP id 2406E260563 for ; Wed, 22 Jul 2015 16:44:52 +0200 (CEST) Received: by oigd21 with SMTP id d21so102752179oig.1 for ; Wed, 22 Jul 2015 07:44:51 -0700 (PDT) In-Reply-To: <55A6380E.4060605@gmail.com> 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: "Alexander E. Patrakov" Cc: ALSA Development Mailing List , Pierre-Louis Bossart List-Id: alsa-devel@alsa-project.org >>> >>> TODO: >>> 1. fixes and alsa-lib updates (compile-tested only for now) >> >> >> http://cgit.freedesktop.org/pulseaudio/pulseaudio/commit/src/modules/alsa/alsa-sink.c?id=cb55b00ccd25d965b1222e74375aee05427a449b >> >> Do you need a new api snd_pcm_hw_params_can_rewind() for the application to >> know pcm device does not support rewind ? > > Yes, we do need that. > > Please see my LAC 2015 paper: http://lac.linuxaudio.org/2015/papers/10.pdf What kind of driver or plugin will have this flag ? snd-aloop, ioplug : pulse and jack Are those usb-audio configure as usb-passthrough inside vm still rewindable ? How about multi plug when one of the slaves has this flag ? file plugin depend on whether slave device support rewind or not