The u-boot supports i2c-over-hid?

[Simon Glass]

Hi,

On Wed, 19 Apr 2023 at 20:33, skyonce at 126.com <skyonce at 126.com> wrote:
>
> hi，
>     For i2c interface keyboard, how should we implement u-boot driver？
>
> Do you have any suggestions

Please try to avoid top posting. See below.

>
>
> ________________________________
> skyonce at 126.com
>
>
> From: Simon Glass
> Date: 2023-04-19 09:45
> To: skyonce at 126.com
> CC: u-boot
> Subject: Re: The u-boot supports i2c-over-hid?
> Hi,
>
> +Heinrich Schuchardt +Heiko Schocher
>
> On Thu, 13 Apr 2023 at 08:58, skyonce at 126.com <skyonce at 126.com> wrote:
> >
> > Hello,
> >     I would like to ask whether i2c-over-hid is not supported under u-boot at present. At present, we have this development need. I would like to ask whether it is feasible to transplant i2c-over-hid from kernel. If not, is there any other way?
> >
>
> I don't see any support for it. Yes, bringing things in from Linux is
> a common approach. Some changes are needed for driver model and some
> differing APIs.

Do you mean HID over I2C? I cannot see anything for the other way
around. But for i2c over hid, see cros_ec_i2c.c which implements I2C
over a Chromium OS EC interface.

For HID over I2C, you could start with a simple driver which uses I2C
to communicate with the device. It would need a new uclass, so it can
be a proper driver. For plumbing it into U-Boot, keyboard-uclass.c
shows how this is done today.

Regards,
Simon