Posts: 4
Joined: Fri Apr 27, 2018 12:57 pm

Generic I2S Audio Driver

Fri Apr 27, 2018 1:29 pm


I'm trying to use the I2S audio output of the Pi as an input for a DSP. I was wondering if there isn't a generic driver/software device to simply use the I2S output (without any configuration via the I2C interface) ?

What I would need:
- 48 kHz sample rate
- 24 bit
- 3,072 MHz Bitclock (64 x fs)
- Bitclock and LR-clock from external oscillator (Raspberry acts as slave)
It would be perfect, if those settings could be changed as a parameter of the device tree overlay.

Basic question: Is it possible to fix the output sample rate and bit depth of the whole system (e.g. to 48 kHz/24 bit)? Or do I have to do that in the running application, e.g. Pulseaudio ?

During my research I found the simple audio card possibility. I didn't find an example which just does some basic audio output. I copy&pasted some fragments together. I'm not really familiar which programming of device tree overlays.
Or is there any existing driver I could use to realise the settings I need ?

Return to “Interfacing (DSI, CSI, I2C, etc.)”