Re: [alsa-devel] Selecting correct input device port.

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.

Takashi