When to start oneway transfer in PS?

[BaronMunchhausen]

Hi,

I am setting up a system, which uses a Custom IP to read data from an ADC and transfer it with AXI DMA to the PS.
I am wondering, how the PS can know when to start the axidma_oneway_transfer to get the data. The PS does start the ADC sampling, but does not exactly know when the custom IP transfers the data.
Can I just start the oneway transfer in blocking mode after starting the ADC and the transfer starts as soon as the transfer finishes? Or might I get some data before the DMA transfer has finished?

Am I right, that the callback function this driver provides, fires after axidma_oneway_transfer has finished and is therefore not suitable for my problem?
Is it possible to use s2mm_introut interrupt of AXI DMA IP with this driver?

I am not sure if got the interaction between the driver and the AXI DMA IP right and would be thankful for any advice.

[samberhanu]

you're better off using the central DMA IP and driver (directly from Xilinx) unless you can FIFO your data and fire-off your PS code right away. The driver will fail if there's no FIFO data available and so you can retry it on that.

On another note, I had some serious issues with this driver and had to accomodate the troubles by writing extra HDL code as no one bothered to respond.
It's a great driver but there are some details that you find out on your own upon trying to use the driver. Good luck