Re: [alsa-lib][PATCH v2 0/2] ctl: deprecate APIs of dimension information

[Takashi Iwai <tiwai@suse.de>]

On Mon, 13 Nov 2017 01:14:09 +0100,
Takashi Sakamoto wrote:
> 
> Hi,
> 
> This patchset is to update my previous one:
> [alsa-devel] [alsa-lib][PATCH 0/2] ctl: deprecate APIs of dimension information
> http://mailman.alsa-project.org/pipermail/alsa-devel/2017-November/126972.html
> 
> 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.
> 
> In a short discussion in my previous patchset, it's clear that actual
> removal of kernel interface is uncertain depending on several conditions.
> Thus the timing to remove the library APIs is not decided yet. This updated
> version reflects the issue in API documentation (but simply removes
> statement of the schedule...).
> 
> [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 dimensional information
>   test: obsolete usage of APIs of dimensional information

Applied both patches now (with your sign-off).

Thanks!


Takashi