Re: [PATCH 00/13] HID: ft260: add UART and GPIO support, plus I2C fixes

[Linus Walleij]

Hi Benjamin, Lee,

On Tue, Sep 1, 2026 at 4:03 PM Benjamin Tissoires <bentiss@xxxxxxxxxx> wrote:

> TBH, I'm not a big fan of having multiple subsystems children into HID.
> Mostly because I can't review the best practive in each of them. However,
> for quite a long time, HID was mostly for input devices, and input is a
> different subsystem.
>
> That being said, there are 2 types of HID devices:
> - ones with defined standard usages (keyboards, mice, touchscreen,
>         battery, etc) and using MFD for those would certainly be overthinking
> - others use raw HID device with a custom protocol (cp2112, mcp2221,
>         ft260), these could be MFD candidates

Surely, as HID start to attract chips which clearly fall into the MFD
category of things, with a plethora of subsystems hooking into the
same HID device, we must find a way for HID devices to spawn
MFD cells?

MFD solved and evolved a system for handling exactly this type
of situation.

Whether there should be an MFD device in the middle spawning
each a HID, GPIO, I2C, UART cell or whether HID device itself should
sit in the nexus and gain the ability to simply spawn out MFD cells
from itself is what we need to figure out.

Yours,
Linus Walleij