[alsa-devel] [PATCH 01/19] ASoC: upd9976: Add Renesas uPD9976 codec driver

[Takashi Iwai]

At Wed, 4 May 2011 23:18:27 +0800,
Lu Guanqun wrote:
> 
> On Wed, May 04, 2011 at 11:07:24PM +0800, Takashi Iwai wrote:
> > At Wed, 4 May 2011 15:34:51 +0100,
> > Mark Brown wrote:
> > > 
> > > On Wed, May 04, 2011 at 09:44:58PM +0800, Lu Guanqun wrote:
> > > 
> > > > +static const struct snd_kcontrol_new upd9976_snd_controls[] = {
> > > > +	SOC_DOUBLE_R_TLV("Headphone & Speaker Volume",
> > > 
> > > Master Volume would be a better name.
> > 
> > Yes, also in general, try to avoid special letters like "&".
> 
> I once used letter "/", but then it failed to create the corresponding
> debugfs directory... :)

Yeah, "/" can be used for control names for now because they aren't
exposed in fs, but better to avoid if possible, too.

> Oh, btw: There are another register that's related to volume control,
> it's before DAC (not added in this patchset yet, for simplicity, will
> add it later). so the connection looks something like this:
> 
> [volume gain A] --> [DAC] --> [Mixer Volume] -> [Output Pins]
> 
> Which volume control should be the master volume? I'm a bit unclear on
> this one.

If it's the only output, any of them can be a "Master" volume.
But if there are other outputs, it shouldn't be named as "Master" at
all. 

Master volume is like Highlander(*), there can be only one :)


Takashi

(*) doesn't mean guys in Edinburgh