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

[Mengdong Lin]

On 07/16/2016 08:58 PM, Takashi Sakamoto wrote:

>
> Current implementation of ALSA SoC part in kernel has no call
> corresponding to sys_ioctl(SNDRV_CTL_IOCTL_ELEM_ADD) or something like
> that, thus I recommend you to drop this line by an additional patch:
> http://git.alsa-project.org/?p=alsa-lib.git;a=blob;f=src/topology/ctl.c;h=b948ac021ceecc116bc1087075743243e4b14055;hb=HEAD#l44
>

Thanks for your suggestions. But this tool is not for directly adding 
controls from the user space.

It's for ADSP firmware vendors to describe the controls/widgets/pcms for 
a specific version of firmware. Previously, these components are hard 
coded in ASoC platforms drivers and not so convenient to share a common 
driver for different firmwares. The topology binary generated by this 
tool will be loaded by ASoC platform driver with a specific firmware 
binary, and so ASoC will create the controls/widgets/pcms that match the 
firmware automatically.

Thanks
Mengdong