> With this patch the Exynos850 HSI2C becomes functional. The only nit-pick > from my side (just a food for thought): do we want to configure USI > related config inside of particular drivers (SPI, I2C, UART)? Or it would > be better design to implement some platform driver for that, so we can > choose USI configuration (SPI/I2C/UART) in device tree? I think this > series is good to be merged as is, but we should probably consider all > upsides and downsides of each option, for the future work. I'm also considering how to support this USI configuration gracefully. Current version of USI is v2 which means there is a v1 version as well. It might be a non-upstream SoC so we don't need to consider it so far. But, there is a possibility that the USI hw version can be bumped for future SoCs. As you probably know, earlier version of the product kernel has a USI SoC driver[1] and it was designed to be configured the USI settings by device tree. Option1) Make a USI driver under soc/samsung/ like [1]. Option2) Use more generic driver such as "reset driver"? This might be required to extend the reset core driver. Option3) Each USI driver(uart/i2c/spi) has its own USI configurations respectively and expose some configurations which can be variable as device tree. [1]: https://github.com/ianmacd/d2s/blob/master/drivers/soc/samsung/usi_v2.c Best Regards, Chanho Park
