> I don't quite understand how to get the clock rate. I tried to add a software > node of clock with property ("clock-frequency", 100000) and referenced by > I2C node. But it didn't work. I've not spent the time to fully understand the code, so i could be very wrong.... >From what you said above, you clock is fixed? So maybe you can do something like: mfld_get_clk_rate_khz() https://elixir.bootlin.com/linux/latest/source/drivers/i2c/busses/i2c-designware-pcidrv.c#L97 How are you instantiating the driver? Can you add to i2_designware_pci_ids[]? Andrew