Hi, I want to have two devices on the same SPI bus.

These devices are:

- SPI nor flash (QSPI compatible)

- my custom device (SPI compatible).

For SPI NOR flash I have the driver in the kernel, for my custom device I do not have such a driver.

My question is - how the access to this particular SPI peripheral can be serialized between these two drivers in order to prevent simultaneous access that would result in a mess on the SPI? Do I have to modify the existing driver for SPI NOR flash or not? 

How about different configurations for these devices - as I mentioned one is QSPI compatible whereas the other one is SPI compatible. Can I reconfigure the SPI bus driver before each "transaction"?

Best regards

Patryk