[alsa-devel] PROC_COEF/PROC_INDEX question

[Takashi Iwai]

At Fri, 7 Aug 2009 17:38:59 +0800,
Wu Fengguang wrote:
> 
> Hello,
> 
> I'm not sure of the usage for GET_PROC_COEF/GET_COEF_INDEX, and found
> that their return value is unstable (changing all the time) for codec:
> 
>         Codec: Realtek ALC888
>         Address: 2
>         Function Id: 0x1
>         Vendor Id: 0x10ec0888
>         Subsystem Id: 0x80860023
>         Revision Id: 0x100202
> 
> For example:
> 
> # hda-verb /dev/snd/hwC0D2 0x20 GET_PROC_COEF 0 
> nid = 0x20, verb = 0xc00, param = 0x0
> value = 0x80
> # hda-verb /dev/snd/hwC0D2 0x20 GET_COEF_INDEX 0
> nid = 0x20, verb = 0xd00, param = 0x0
> value = 0xe
> # hda-verb /dev/snd/hwC0D2 0x20 GET_PROC_COEF 0 
> nid = 0x20, verb = 0xc00, param = 0x0
> value = 0x9c00
> # hda-verb /dev/snd/hwC0D2 0x20 GET_COEF_INDEX 0
> nid = 0x20, verb = 0xd00, param = 0x0
> value = 0xf
> 
> I wonder if this is the normal case?

AFAIK, depending on the mode, the index is incremented automatically.


Takashi