Re: [PATCH v3] mfd: ch341: add driver for the WCH CH341 in I2C/GPIO mode

From: Frank Zago
Date: Tue Mar 15 2022 - 23:49:10 EST


Hello Lee,

>> Changes from v2:
>> - bug fixes
>> - more robust USB enumeration
>> - Changed to an MFD driver as suggested
>
> Perhaps you should have engaged with me before potentially wasting
> your valuable time.
>
> MFD is designed to take a parent platform driver and split it out into
> various sub-systems. If you don't use the MFD Core API (which is the
> case here) it is not an MFD. MFD is not a dumping ground for
> collections of random device drivers.
>
> I have no problem with you placing registration and core code inside
> MFD (that *is* what it was designed for), but the leaf 'functionality'
> should be placed in more appropriate locations.
>
> I2C => drivers/i2c
> SPI => drivers/spi
> GPIO => drivers/gpio (or perhaps drivers/pinctrl)
> USB => drivers/usb
> UART => drivers/tty/serial
>
> Etc ... Find places for everything.
>
> Anything left over, give to Greg (drivers/misc). :)
>

AFAICS that works if the driver is built-in, but not as a module.

I'd prefer that driver to be a module if desired, and have all its files in the same
place instead of scattered in various directories.

I can try drivers/misc if it's a better place.

Frank.