Re: [PATCH 1/8] dt-bindings: phy: Document ST STM32MP25 USB2-FEMTO PHY

[Marek Vasut <marex@nabladev.com>]

On 8/13/26 12:51 AM, Rob Herring wrote:
> On Wed, Aug 12, 2026 at 08:30:33PM +0200, Marek Vasut wrote:
>> On 8/12/26 1:22 PM, Krzysztof Kozlowski wrote:
>>> On 12/08/2026 12:56, Marek Vasut wrote:
>>>> On 8/12/26 12:15 PM, Krzysztof Kozlowski wrote:
>>>>> On Wed, Aug 12, 2026 at 02:55:41AM +0200, Marek Vasut wrote:
>>>>>> From: Pankaj Dev <pankaj.dev@st.com>
>>>>>>
>>>>>> Document USB2 PHY for STM32MP25 USB2 controllers, which includes the
>>>>>> USB2.0 host-only controller and USB 2.0 part of the DWC3 controller.
>>>>>> Two such PHYs in total are present in STM32MP25 SoC, they both are
>>>>>> slightly different, therefore they use different compatible string
>>>>>
>>>>> What is slightly different? This should be either here, or better, in
>>>>> "description" part.
>>>>
>>>> They are both Synopsys FEMTO-PHY , but they are each attached to a
>>>> different controller (one to USB 2.0 host , the other to DWC3 DRD) , and
>>>> their control bits in the system controller register are different for
>>>> each variant.
>>>>
>>>> I extended the description in V2.
>>>
>>> Depending on the actual difference, this rather belongs to the phandle
>>> to syscon, instead of separate compatible.
>>
>> Modeling that in the phandle to syscon won't scale, the PHY driver is simple
>> thus far and does not control all the bits in that syscon, if we were to
>> somehow extend the phandle to syscon to describe the various bit mappings
>> and differences in it, it would look awful quickly. Hence the separate
>> compatible strings, so the driver can match on them, derive match data from
>> them and use the match data to figure out differences of each instance.
> 
> There's no 'reg' so the syscon is the only control interface, right?

Correct.

> So this should be child node of the syscon (with a reg property).
All right, will do in V2 (already done locally).

Thanks !