From mboxrd@z Thu Jan 1 00:00:00 1970 From: Takashi Sakamoto Subject: [alsa-lib][PATCH 0/2] ctl: deprecate APIs of dimension information Date: Sat, 4 Nov 2017 11:24:24 +0900 Message-ID: <20171104022426.16230-1-o-takashi@sakamocchi.jp> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from smtp-proxy002.phy.lolipop.jp (smtp-proxy002.phy.lolipop.jp [157.7.104.43]) by alsa0.perex.cz (Postfix) with ESMTP id 38BA2266F36 for ; Sat, 4 Nov 2017 03:24:44 +0100 (CET) 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: tiwai@suse.de, perex@perex.cz Cc: alsa-devel@alsa-project.org List-Id: alsa-devel@alsa-project.org Hi, In ALSA control interface of asound.h, 'struct snd_ctl_elem_info' has 'dimen' member to deliver information for multi-dimensional array, however there's no common way to handle the member. As a result, drivers can force userspace applications to handle the information by inconsistent ways. A series of echoaudio drivers is an actual example of the inconsistent usage. This issue was addressed in a commit 51db452df07b ('Revert "ALSA: echoaudio: purge contradictions between dimension matrix members and total number of members"') to Linux kernel[1]. Fortunately, at present, this feature of interface is just used by the drivers, and there's a way to obsolete usage of the feature. We can obsolete it without large impacts to userland. As a result of discussion at Linux miniconference 2017, usage of 'dimen' member of 'struct snd_ctl_elem_info' is going to be deprecated for future removal. This patchset is for proposed tasks at a development period of Linux kernel v4.15[3]. Some APIs of dimension information are deprecated. [1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/sound/pci/echoaudio?id=51db452df07bb4c5754b73789253ba21681d9dc2 [2] [alsa-devel] [ANNOUNCE] Audio Mini Summit 2017 at Prague, Oct 27 http://mailman.alsa-project.org/pipermail/alsa-devel/2017-July/123110.html [3] https://github.com/takaswie/presentations/blob/master/20171027/contents.md Takashi Sakamoto (2): ctl: deprecate APIs of dimension information test: obsolete usage of APIs of dimension information src/control/control.c | 12 ++++++++++++ test/user-ctl-element-set.c | 31 ------------------------------- 2 files changed, 12 insertions(+), 31 deletions(-) -- 2.11.0