From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ricardo Biehl Pasquali Subject: Re: Coherence of status structure after SYNC_PTR Date: Fri, 28 Dec 2018 14:28:24 -0200 Message-ID: <20181228162824.GA28189@localhost.localdomain> References: <20181227172224.GA18933@localhost.localdomain> <20181228034549.GA22203@workstation> <20181228042124.GA30249@workstation> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mail-qt1-f171.google.com (mail-qt1-f171.google.com [209.85.160.171]) by alsa0.perex.cz (Postfix) with ESMTP id C066E267A78 for ; Fri, 28 Dec 2018 17:28:30 +0100 (CET) Received: by mail-qt1-f171.google.com with SMTP id u47so19207209qtj.6 for ; Fri, 28 Dec 2018 08:28:30 -0800 (PST) Content-Disposition: inline In-Reply-To: <20181228042124.GA30249@workstation> 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: Takashi Sakamoto Cc: alsa-devel@alsa-project.org List-Id: alsa-devel@alsa-project.org On Fri, Dec 28, 2018 at 01:21:24PM +0900, Takashi Sakamoto wrote: > On Fri, Dec 28, 2018 at 12:45:49PM +0900, Takashi Sakamoto wrote: > > I note that there're some levels of timestamp and autio timestamp. > > Additionally, audio timestamp is updated only in any hardware/software IRQs, > > thus it's not available with 'no-period-wakeup' runtime, FYI. > > Oops. No, the audio timestamp can be updated in updating process of > hardware pointer. A call of ioctl with SNDRV_PCM_IOCTL_STATUS and > SNDRV_PCM_IOCTL_STATUS_EXT can return updated audio timestamp. Thank you for the explanation! Regarding the alsa-lib, pcm_hw, htimestamp(): Although not needed, adding a 'break' in the loop when 'mmap_status_fallbacked' is true would avoid another ioctl. Cheers! pasquali