From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.4 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6ED78C433E0 for ; Thu, 11 Jun 2020 09:10:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 488E52086A for ; Thu, 11 Jun 2020 09:10:00 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=perex.cz header.i=@perex.cz header.b="MWNjhacI" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726947AbgFKJJ6 (ORCPT ); Thu, 11 Jun 2020 05:09:58 -0400 Received: from mail1.perex.cz ([77.48.224.245]:41830 "EHLO mail1.perex.cz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726899AbgFKJJ5 (ORCPT ); Thu, 11 Jun 2020 05:09:57 -0400 Received: from mail1.perex.cz (localhost [127.0.0.1]) by smtp1.perex.cz (Perex's E-mail Delivery System) with ESMTP id B0355A0040; Thu, 11 Jun 2020 11:09:54 +0200 (CEST) DKIM-Filter: OpenDKIM Filter v2.11.0 smtp1.perex.cz B0355A0040 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=perex.cz; s=default; t=1591866594; bh=L61ocGqIHqYghRmVw21trPpdQrhMiQuIAwZnA/ZLpiU=; h=Subject:To:Cc:References:From:Date:In-Reply-To:From; b=MWNjhacIeUj+P7/+qznHakCsQ8vxQKkiGNFozy9GxhJuBDUi+6kXVqhY9ra5D4nJs CK+at8tC0b/USD4QYjYp+HkywuBa8m6WDWANbcD4/1KzfKEaeQ3/ZTusK4rhA9hmu/ C84Xs4OxhpUNwpHzlhrQsCVmOf7TKyMh8wToEh3Q= Received: from p50.perex-int.cz (unknown [192.168.100.94]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: perex) by mail1.perex.cz (Perex's E-mail Delivery System) with ESMTPSA; Thu, 11 Jun 2020 11:09:47 +0200 (CEST) Subject: Re: [RFC PATCH] ALSA: compress: Fix gapless playback state machine To: Charles Keepax , Vinod Koul Cc: alsa-devel@alsa-project.org, broonie@kernel.org, Srinivas Kandagatla , tiwai@suse.com, linux-kernel@vger.kernel.org References: <20200610100729.362-1-srinivas.kandagatla@linaro.org> <817d009e-fa09-e897-cfc3-997bf1dd5e30@perex.cz> <20200610105820.GA1393454@vkoul-mobl> <20200611084659.GO71940@ediswmail.ad.cirrus.com> From: Jaroslav Kysela Message-ID: <6a984302-ff01-e326-d338-e50e1f532cd9@perex.cz> Date: Thu, 11 Jun 2020 11:09:47 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.8.0 MIME-Version: 1.0 In-Reply-To: <20200611084659.GO71940@ediswmail.ad.cirrus.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Dne 11. 06. 20 v 10:46 Charles Keepax napsal(a): > On Wed, Jun 10, 2020 at 04:28:20PM +0530, Vinod Koul wrote: >> On 10-06-20, 12:40, Jaroslav Kysela wrote: >>> Dne 10. 06. 20 v 12:07 Srinivas Kandagatla napsal(a): >>>> For gapless playback call to snd_compr_drain_notify() after >>>> partial drain should put the state to SNDRV_PCM_STATE_RUNNING >>>> rather than SNDRV_PCM_STATE_SETUP as the driver is ready to >>>> process the buffers for new track. >>>> >>>> With existing code, if we are playing 3 tracks in gapless, after >>>> partial drain finished on previous track 1 the state is set to >>>> SNDRV_PCM_STATE_SETUP which is then moved to SNDRV_PCM_STATE_PREPARED >>>> after data write. With this state calls to snd_compr_next_track() and >>>> few other calls will fail as they expect the state to be in >>>> SNDRV_PCM_STATE_RUNNING. >>>> >>>> Here is the sequence of events and state transitions: >>>> >>>> 1. set_params (Track 1), state = SNDRV_PCM_STATE_SETUP >>>> 2. set_metadata (Track 1), no state change, state = SNDRV_PCM_STATE_SETUP >>>> 3. fill and trigger start (Track 1), state = SNDRV_PCM_STATE_RUNNING >>>> 4. set_next_track (Track 2), state = SNDRV_PCM_STATE_RUNNING >>>> 5. partial_drain (Track 1), state = SNDRV_PCM_STATE_SETUP >>>> 6 snd_compr_drain_notify (Track 1), state = SNDRV_PCM_STATE_SETUP >>>> 7. fill data (Track 2), state = SNDRV_PCM_STATE_PREPARED >>>> 8. set_metadata (Track 3), no state change, state = SNDRV_PCM_STATE_PREPARED >>>> 9. set_next_track (Track 3), !! FAILURE as state != SNDRV_PCM_STATE_RUNNING >>> >>> >>> The snd_compr_drain_notify() is called only from snd_compr_stop(). Something >>> is missing in this sequence? >> >> It is supposed to be invoked by driver when partial drain is complete.. >> both intel and sprd driver are calling this. snd_compr_stop is stop >> while draining case so legit >> > > Not sure I follow this statement, could you elaborate a bit? > snd_compr_stop putting the state to RUNNING seems fundamentally > broken to me, the whole point of snd_compr_stop is to take the > state out of RUNNING. Yes. I agree. It seems that the acknowledge for the partial drain should be handled differently. Jaroslav > > Thanks, > Charles > -- Jaroslav Kysela Linux Sound Maintainer; ALSA Project; Red Hat, Inc.