[alsa-devel] [PATCH v2 0/5] topology: Enhance support for private data

[Lin, Mengdong]

> -----Original Message-----
> From: Takashi Sakamoto [mailto:o-takashi at sakamocchi.jp]
> Sent: Monday, July 18, 2016 11:43 AM
 
> I know all of what you explained. Therefore, You misunderstand about my
> suggestion.
> 
> What I suggested is to drop a support of SNDRV_CTL_ELEM_ACCESS_USER
> flag from current topology implementation in userspace library, because
> current implementation of ALSA SoC part doesn't support it.
> 
> In ALSA SoC part, snd_ctl_new1() is called to add a control element set as a
> result of parsing binary blob generated by topology implementation.
> 
> In snd_ctl_new1(), SNDRV_CTL_ELEM_ACCESS_USER flag is dropped, in these
> lines:
> http://git.kernel.org/cgit/linux/kernel/git/tiwai/sound.git/tree/sound/core/c
> ontrol.c#n263
> 
> Totally, the flag cannot be supported by current implementation of topology
> in kernel. Thus, in userspace, we should drop this line to prevent users from
> confusions:
> http://git.alsa-project.org/?p=alsa-lib.git;a=blob;f=src/topology/ctl.c;h=b94
> 8ac021ceecc116bc1087075743243e4b14055;hb=HEAD#l44
> 
> That's all what I mentioned. If something unclear, please tell it to me.

Yes, you're right. snd_ctl_new1() dropped SNDRV_CTL_ELEM_ACCESS_USER flag.
I'll remove this from the topology user space tool to avoid confusion.

Thanks again
Mengdong