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=-4.0 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 37505C433DF for ; Thu, 23 Jul 2020 12:38:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1C16520768 for ; Thu, 23 Jul 2020 12:38:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728630AbgGWMiK (ORCPT ); Thu, 23 Jul 2020 08:38:10 -0400 Received: from mx2.suse.de ([195.135.220.15]:48480 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726109AbgGWMiK (ORCPT ); Thu, 23 Jul 2020 08:38:10 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 5E6E4AAC5; Thu, 23 Jul 2020 12:38:17 +0000 (UTC) Date: Thu, 23 Jul 2020 14:38:09 +0200 Message-ID: From: Takashi Iwai To: Srinivas Kandagatla Cc: broonie@kernel.org, vkoul@kernel.org, perex@perex.cz, tiwai@suse.com, lgirdwood@gmail.com, alsa-devel@alsa-project.org, linux-kernel@vger.kernel.org, ckeepax@opensource.cirrus.com Subject: Re: [RFC PATCH v2 0/6] ALSA: compress: add support to change codec profile in gapless playback In-Reply-To: <20200721170007.4554-1-srinivas.kandagatla@linaro.org> References: <20200721170007.4554-1-srinivas.kandagatla@linaro.org> User-Agent: Wanderlust/2.15.9 (Almost Unreal) SEMI/1.14.6 (Maruoka) FLIM/1.14.9 (=?UTF-8?B?R29qxY0=?=) APEL/10.8 Emacs/25.3 (x86_64-suse-linux-gnu) MULE/6.0 (HANACHIRUSATO) MIME-Version: 1.0 (generated by SEMI 1.14.6 - "Maruoka") Content-Type: text/plain; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 21 Jul 2020 19:00:01 +0200, Srinivas Kandagatla wrote: > > For gapless playback it is possible that each track can have different > codec profile with same decoder, for example we have WMA album, > we may have different tracks as WMA v9, WMA v10 and so on > Or if DSP's like QDSP have abililty to switch decoders on single stream > for each track, then this call could be used to set new codec parameters. > > Existing code does not allow to change this profile while doing gapless > playback. > > This patchset adds new SNDRV_COMPRESS_SET_CODEC_PARAMS IOCTL along with > flags in capablity structure to allow userspace to set this new > parameters required which switching codec profile, either for gapless > or cross fade usecase. One idea that came up at the previous audio conference regarding this implementation was to just allow SET_PARAMS during the stream is running (only if the driver sets the capability) instead of introducing yet a new ioctl and an ops. Would it make sense? I have no big objection to add a new ioctl if other people agree, though. thanks, Takashi