Alsa Driver - sound from gpio

[Raphael Philipe]

Hi!

I'm a newbie on ALSA architecture. I would like to known if it would
be possible to create a sound driver for a a PCM sound beeing acquired
by the GPIO of a processor, like the ARM of a Beaglebone Black.

Beaglebone has more than 32 bits of gpio so I intend to acquire the
audio signal through a A/D CI (sigma delta) connected to a FPGA that
would provide it to the Beaglebone Black in parallel form (PCM code),
through the GPIO.

Is that possible?

Regards