[alsa-devel] [PATCH] ALSA: hda - Remove ignore_misc_bit

David Henningsson david.henningsson at canonical.com
Tue Sep 18 10:40:19 CEST 2012

[removing CC to bug, since this has gone a bit offtopic]

On 09/18/2012 10:26 AM, Takashi Iwai wrote:
> At Mon, 17 Sep 2012 09:39:01 +0200,
> David Henningsson wrote:
>>> But the jack detection controls don't follow this yet.  Maybe we can
>>> set such a jack control as inactive state when the jack detection is
>>> disabled.
>>> (And this reminds me that we can cut off "Phantom" name hack by
>>>    following the same rule -- just set the control inactive when it has
>>>    no real detection.  But it still appears in control list.)
>> Looking at the alsa-lib API, this seems doable. It seems possible to
>> figure out using snd_hctl_elem_info and then
>> snd_ctl_elem_info_is_inactive. If it is also runtime changeable (i e
>> depending on some other mixer control), we need a callback to fire on
>> the hctl.
> Why are you using snd_hctl?  For looking over jack controls, using
> snd_ctl_* is more straightforward.

Ehm, because I'm one of the confused users who doesn't know why there 
are four different APIs (ctl, hctl, mixer, smixer) in the first place? 
:-) And because I started with looking at the code to amixer. IIRC.

> Also, which callback are you thinking of?  The phantom jack is
> basically just a placeholder, so there should be no activity from
> itself.

You said something about the user telling the system to disable jack 
detection - if so, (s)he will probably do so by changing a (new?) 
kcontrol, which would then change the inactivity status of the jack 
kcontrol, and then we need to pick that change up.

David Henningsson, Canonical Ltd.

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