At Thu, 14 Apr 2011 22:28:45 +0800, Lu Guanqun wrote:
On Thu, Apr 14, 2011 at 10:19:36PM +0800, Lu Guanqun wrote:
On Thu, Apr 14, 2011 at 05:54:11PM +0800, Takashi Iwai wrote:
At Mon, 11 Apr 2011 07:56:22 -0700, Mark Brown wrote:
+static const struct snd_kcontrol_new sta529_new_snd_controls[] = {
- SOC_ENUM("pwm select", pwm_src_enum),
- SOC_ENUM("mode select", mode_src_enum),
+};
ALSA control names are idiomatically things like "PWM Select" with capitalisation.
Actually, the capital words are no mandatory requirement (although it's conventionally so). It's just alsa-mixer grouping rule that requires the capital words "Play", "Capture", "Volume", "Switch", etc.
Hi Takashi,
Where can I find these alsa-mixer grouping rule? So that I can obey these rules and make them appear in the right view in alsamixer.
Hi Takashi,
I'm reading this comment from file `sound/aoa/codecs/tas.c`:
/* If we name this 'Input Source', it properly shows up in * alsamixer as a selection, * but it's shown under the * 'Playback' category. * If I name it 'Capture Source', it shows up in strange * ways (two bools of which one can be selected at a * time) but at least it's shown in the 'Capture' * category. * I was told that this was due to backward compatibility, * but I don't understand then why the mangling is *not* * done when I name it "Input Source"..... */I'm wondering what's the story behind? Can you shed some lights?
In alsa-mixer abstraction, the "Capture Source" enum control is split over multiple switches (a switch per enum item). This was a historical design at the time SoundBlaster is still standard.
One of the problems with this abstraction is that it can't handle multiple capture-source controls. So, many drivers use nowadays "Input Source" control instead. But, in the earlier alsa-lib, this wasn't handled as the capture control, thus it appears as a global (both directional) control in alsamixer.
Now, this control is handled as a capture control in alsa-lib, so the appearance is corrected.
Takashi