Re: [PATCH v3 3/6] arm64: dts: lx2160a-qds: make the QIXIS CPLD use the simple-mfd-i2c.c driver

[Krzysztof Kozlowski <krzk@kernel.org>]

On 15/05/2025 17:56, Ioana Ciornei wrote:
> The MDIO mux on the LX2160A-QDS never worked in mainline. This is
> because the on-board QIXIS FPGA does not have a driver that could probe
> it and register an I2C regmap for it which could, afterwards, be used by
> the child devices - such as the mux-controller.
> 
> There is a downstream driver for the QIXIS CPLD:
> 
> https://github.com/nxp-qoriq/linux/blob/lf-6.12.y/drivers/soc/fsl/qixis_ctrl.c
> 
> That driver is very similar to the already existing drivers/mfd/simple-mfd-i2c.c,
> and the hardware works with the simple-mfd-i2c driver, so there isn't
> any reason to upstream the other one.
> 
> Since we want the QIXIS CPLD to have child nodes with "reg" and the
> current format lacks that, change the compatible string so that we make
> it clear that by using the simple-mfd-i2c driver, and its
> fsl,lx2160a-qds-qixis-cpld compatible, we expect dt nodes children with
> the reg property.

We are repeating the same over and over and I am getting bored. I do not
see any reason to change the compatible. Whether you want to use
simple-mfd driver or not, is not relevant here. Does not matter. Whether
device was really working or not, is not relevant either.

There is a device with given compatible, explain why this compatible is
wrong. Without arguments for that, old compatible must stay.



Best regards,
Krzysztof