2014-10-30 下午12:38 於 "dE" de.techno@gmail.com 寫道：
On 10/29/14 13:06, Takashi Iwai wrote:
At Tue, 28 Oct 2014 09:57:18 +0530, dE wrote:
As I learn't in this mailng list, a device can typically handle only one stream at a time unless it supports hardware mixing which's exposed via subdevices in ALSA
What does subdevice mean for input device?
When a device can do multiplexing, the driver can give multiple substreams (= subdevices).
Do they mark physical ports for input? If not how do I record from a specific input port?
You can pass the subdevice number explicity. It's -1 as default, which means to select the next free one.
Is it automatically selected by the card?
And what's 'input source' in ALSA mixer?
It's usually a MUX to select the input source, e.g. line in or mic.
Input source for single subdevice right? I've 3 sub device, does it have
to do anything with the fact that I've 3 input source in alsamixer? Do the 3 input source mark 3 different subdevices?
So far, only those 10 channel hda codecs have three ADC
Due to recent change in snd-hda-intel, if your desktop previously had three subdevices, the new driver create analog capture device with one subdevice and alt analog capture with two subdevices