Re: Reg: New MFD Driver for my PCIe Device

[Greg KH <gregkh@linuxfoundation.org>]

On Mon, Nov 08, 2021 at 11:04:31AM +0000, Lee Jones wrote:
> On Mon, 08 Nov 2021, Kumaravel.Thiagarajan@microchip.com wrote:
> 
> > Dear Lee Jones,
> > 
> > I am Kumaravel Thiagarajan from Microchip, India and I am new to Linux Kernel development.
> > 
> > I am currently working on linux kernel driver for one of our PCIe based devices whose BAR 0 maps interface registers for a gpio controller, an OTP memory device controller and an EEPROM device controller into the host processor's memory space.
> > 
> > Based on earlier inputs from Linus Walleij, I have developed this as a multi-function device driver - First MFD driver (drivers/mfd) gets loaded for the PCIe device and then it spawns two child devices for OTP/EEPROM and GPIO separately.
> 
> You may wish to speak with Greg about your architectural decisions.
> 
> He usually dislikes the creation of platform devices from PCI ones.

Yes, that is NOT ok.

Platform devices are only for devices that are actually on a platform
(i.e. described by DT or other firmware types).  PCI devices are NOT
platform devices, please use the correct apis for this instead (i.e. the
aux bus)

thanks,

greg k-h