Hi,
we have a basic (without external interrupts, so polling)
communication going with an ADS1258EVM via McSPI3.
But we now face the problem of how to configure the system's DMA
controller and McSPI port to read a new 32-bit word from the A/D
converter each time it signals that a new sample has been converted.
It does this through a (negated) Data Ready signal, which is usually
high and goes low when a new sample is ready to be picked up.
I had a look into the pdfs on sDMA, GPIO, McSPI and INTC modules, and
although I saw no mention of external interrupts in the McSPI pdf, it
seems as though the SDMA can receive external interrupts through the
INTC module, which can itself receive interrupts from any of the 6
GPIO modules. Still, I'm hoping that someone has already done
something on SPI and external interrupts because I'm not too convinced
I could pull off writing a whole Linux driver for this on my own.
Perhaps someone even has example code for talking to a different A/D
converter which we could adjust for our's?
There seem to be some preparations for using DMA and some kind of
interrupts in the omap2_mcspi.c source file, but is it really
implemented? I could not find any further reference to e.g. the
constant OMAP2_MCSPI_IRQENABLE which is defined there. If it is
implemented, how should it be used?
Can anyone help?
KUNAL