I2S/SPI DMA RX from audio chip not firing interrupts

[chiVelle]

Interrupts are being fired but everything in the DMA Memory0 location is garbage data. I checked the SPI2 DR register and it is always 0 when DMA is enabled. I hooked a scope up to the I2S pins and verified PCM data is being transferred. The I2SCFGR register looks accurate when reading it during DMA enabled. Any ideas on this one?

[Abhishek]

The PC3 pin is being used by the on-board PDM mic. Is there a logic contention?
Or, try changing CPOL bit in I2SCFGR and see if it has any effect.

Best Regards
Abhishek

[Giovanni]

Hi,

I committed an I2S driver in the 3.0 branch, apparently it is able to read the PDM stream from the F4-Discovery microphone. I had to change the driver model a bit in order to save DMA channels (TX-only and RX-only require only one channel, it is useless always allocate two).

Now I am a bit stuck with further testing, suggestions? I'll stop on this one for the time being.

Giovanni

[chiVelle]

I will try to integrate this into my project soon for testing and will report issues/findings. Looking through the driver I don't see anything that stands out as non-compatible with the 2.6 kernel, is this correct? I'd like to integrate this into my 2.6.3 project. Thanks for the post notifying me of the commit.

[Giovanni]

You have just to replace those osal and OSAL_ functions/macros with their ch/CH_ equivalents in 2.6.

Giovanni