Eldad Zack wrote:
On Tue, 5 Feb 2013, Clemens Ladisch wrote:
I thought I'd try to use implicit feedback with my simple audio device: [...] This works fine when playing something:
...
But when I then try to record at the same time, the driver refuses to configure the input endpoint (to the only format, which is already set): And despite that "alreay in use" check, the input endpoint is affected so much that playback breaks.
Is full duplex supposed to work? Does it work with other devices?
This is probably a "yes, but" :) I use my device mostly full duplex, but with jack opening both playback and capture at the same time.
I assume you are opening two different streams, one for playback and one for capture.
Jack *also* uses two different streams, but it opens them at the same time.
Can you try using jackd -d alsa -d hw:x with the device and see if that works for you?
That works. This means that there is a race condition in the driver, or that the different open/hw_params/prepare order trips it up.
Anyway, I feel safe now to enable implicit feedback for other devices.
Regards, Clemens