Re: [PATCH 1/3] dt-bindings: usb: Add binding for TI USB8041 hub controller

Krzysztof Kozlowski
2022-07-12T21:12:14Z

On 12/07/2022 19:25, Matthias Kaehlcke wrote:
> Hi Alexander,
>
> On Tue, Jul 12, 2022 at 05:06:25PM +0200, Alexander Stein wrote:
>> The TI USB8041 is a USB 3.0 hub controller with 4 ports.
>>
>> This initial version of the binding only describes USB related aspects
>> of the USB8041, it does not cover the option of connecting the controller
>> as an i2c slave.
>>
>> Signed-off-by: Alexander Stein <alexander.stein@ew.tq-group.com>
>> ---
>> Well, this is essentially a ripoff of
>> Documentation/devicetree/bindings/usb/realtek,rts5411.yaml with USB IDs
>> replaced, reset-gpio added and example adjusted.
>> IMHO this should be merged together with realtek,rts5411.yaml. Is it ok
>> to rename bindings files? I guess a common onboard-usb-hub.yaml matching
>> the driver seens reasonable. Any recommendations how to proceed?
>
> It's a tradeoff between keeping the individual bindings simple and avoid
> unnecessary duplication. The current RTS5411 and TI USB8041 bindings are
> very similar, which suggests combining them. However over time hubs with
> diverging features could be added (e.g. with multiple regulators, a link
> to an I2C/SPI bus, a clock, ...). With that a common binding might become
> too messy.
>
> From a quick look through Documentation/devicetree/bindings it doesn't
> seem common to have generic bindings that cover components from multiple
> vendors. In that sense I'm leaning towards separate bindings.
>
> Rob, do you have any particular preference or suggestion?

Not Rob, but my suggestion is not to merge bindings of unrelated
devices, even if they are the same class. By unrelated I mean, made by
different companies, designed differently and having nothing in common
by design. Bindings can be still similar, but should not be merged just
because they are similar.

Best regards,
Krzysztof