[alsa-devel] [PATCH] hda_proc - Add output of Vref, additional pcaps, and proccaps to proc output

Takashi Iwai tiwai at suse.de
Thu Jan 17 18:20:13 CET 2008

At Thu, 17 Jan 2008 09:11:00 -0800,
Tobin Davis wrote:
> On Thu, 2008-01-17 at 17:58 +0100, Takashi Iwai wrote:
>     At Thu, 17 Jan 2008 09:46:06 -0400,
>     Andrew Paprocki wrote:
>     > 
>     > This adds additional pincaps which were not previously output. Also, Vref
>     > capabilities are output per-pin along with the current Vref pinctl setting
>     > if the NID supports Vref. Also added: processing widgets and proccaps, as
>     > well as processing coefficient and coefficient index from the Realtek Define
>     > Registers per the ALC883 datasheet.
>     > 
>     > Signed-off-by: Andrew Paprocki <andrew at ishiboo.com>
>     Did you check whether this doesn't break Claudio's codecgraph parser?
>     If it's OK, I'd like to apply it, of course...
>     Takashi
> You're kidding, right?  Adding more details about a codec is more useful at this
> point than making sure a non-essential script (that can be easily modified)
> isn't broken.

Well, now we have some parser program, then it's the high time to
think about the proc output consistent in a certain level.  So far,
it's just written to be readable for human being.  But, now we'd need
to make it also easily readable by dumb programs, too.

> What I want to know is if we can add even more to /proc, like EAPD status (not
> just capabilities), jack sense, etc.  These are useful bits of information, not
> only for driver development, but also could be useful for userspace tools that
> can monitor these.  Imagine having your system auto adjust from 5.1 surround
> settings to optimal headphone settings (not just automute) when you plug in your
> headphones.

The jack-sense is a bit problem.  I once had a laptop that causes
codec errors when issuing a jack-sense command without unsolicited
events.  So, I'd say, let's be as conservative as possible for the

Moreover, we can read any commands via hwdep ioctl easily now...


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