Initialization order

Hello,
I have a LS1021A connected to a device via SPI bus and PCIe bus. To enable the PCIe bus on this device , I need to write registers via the SPI bus.
I created a small SPI driver using the regmap layer to access the chip and I am able to  display or write registers via md and mw.

I have tried (core)device_initcall opening the device using open_and_lseek but it is either called after ls_pcie_probe or too early and failed

What would be the best approach to do this initialization before ls_pcie_probe is called?


Cheers,
Renaud