Re: [PATCH v2] dt-bindings: usb: Add binding for Microchip usb5744 hub controller

[Michal Simek <michal.simek@amd.com>]

On 5/9/23 18:04, Krzysztof Kozlowski wrote:
> On 09/05/2023 16:19, Michal Simek wrote:
>>
>>
>> On 5/7/23 10:07, Krzysztof Kozlowski wrote:
>>> On 05/05/2023 15:25, Michal Simek wrote:
>>>> The Microchip usb5744 is a SS/HS USB 3.0 hub controller with 4 ports.
>>>> The binding describes USB related aspects of the USB5744 hub, it as
>>>> well cover the option of connecting the controller as an i2c slave.
>>>> When i2c interface is connected hub needs to be initialized first.
>>>> Hub itself has fixed i2c address 0x2D but hardcoding address is not good
>>>> idea because address can be shifted by i2c address translator in the
>>>> middle.
>>>>
>>>> Signed-off-by: Piyush Mehta <piyush.mehta@amd.com>
>>>> Signed-off-by: Michal Simek <michal.simek@amd.com>
>>>> ---
>>>>
>>>> Changes in v2:
>>>> - fix i2c-bus property
>>>> - swap usb2.0/3.0 compatible strings
>>>> - fix indentation in example (4 spaces)
>>>> - add new i2c node with microchip,usb5744 compatible property
>>>>
>>>> It looks like that usb8041 has also an optional i2c interface which is not
>>>> covered. But it is mentioned at commit 40e58a8a7ca6 ("dt-bindings: usb:
>>>> Add binding for TI USB8041 hub controller").
>>>>
>>>> i2c-bus name property was suggested by Rob at
>>>> https://lore.kernel.org/all/CAL_JsqJedhX6typpUKbnzV7CLK6UZVjq3CyG9iY_j5DLPqvVdw@mail.gmail.com/
>>>> and
>>>> https://lore.kernel.org/all/CAL_JsqJZBbu+UXqUNdZwg-uv0PAsNg55026PTwhKr5wQtxCjVQ@mail.gmail.com/
>>>>
>>>> the question is if adding address like this is acceptable.
>>>> But it must be specified.
>>>>
>>>> Driver will follow based on final dt-binding.
>>>>
>>>> $ref: usb-device.yaml# should be also added but have no idea how to wire it
>>>> up to be applied only on usb node not i2c one.
>>>>
>>>> ---
>>>>    .../bindings/usb/microchip,usb5744.yaml       | 110 ++++++++++++++++++
>>>>    1 file changed, 110 insertions(+)
>>>>    create mode 100644 Documentation/devicetree/bindings/usb/microchip,usb5744.yaml
>>>>
>>>> diff --git a/Documentation/devicetree/bindings/usb/microchip,usb5744.yaml b/Documentation/devicetree/bindings/usb/microchip,usb5744.yaml
>>>> new file mode 100644
>>>> index 000000000000..7e0a3472ea95
>>>> --- /dev/null
>>>> +++ b/Documentation/devicetree/bindings/usb/microchip,usb5744.yaml
>>>> @@ -0,0 +1,110 @@
>>>> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
>>>> +%YAML 1.2
>>>> +---
>>>> +$id: http://devicetree.org/schemas/usb/microchip,usb5744.yaml#
>>>> +$schema: http://devicetree.org/meta-schemas/core.yaml#
>>>> +
>>>> +title: Microchip USB5744 4-port Hub Controller
>>>> +
>>>> +description:
>>>> +  Microchip's USB5744 SmartHubTM IC is a 4 port, SuperSpeed (SS)/Hi-Speed (HS),
>>>> +  low power, low pin count configurable and fully compliant with the USB 3.1
>>>> +  Gen 1 specification. The USB5744 also supports Full Speed (FS) and Low Speed
>>>> +  (LS) USB signaling, offering complete coverage of all defined USB operating
>>>> +  speeds. The new SuperSpeed hubs operate in parallel with the USB 2.0
>>>> +  controller, so 5 Gbps SuperSpeed data transfers are not affected by slower
>>>> +  USB 2.0 traffic.
>>>> +
>>>> +maintainers:
>>>> +  - Piyush Mehta <piyush.mehta@amd.com>
>>>> +  - Michal Simek <michal.simek@amd.com>
>>>> +
>>>> +select:
>>>> +  properties:
>>>> +    compatible:
>>>> +      contains:
>>>> +        const: microchip,usb5744
>>>> +  required:
>>>> +    - compatible
>>>
>>> I don't understand why do you need this select. It basically disables
>>> schema matching for other ones.
>>
>> I didn't find a way how to have usbXXX,XXXX compatible strings and
>> microchip,usb5744 compatible in the same file. I am definitely lacking knowledge
>> how to write it properly that's why any advise is welcome.
> 
> Hm, if you just have both of them like you have now, what happens?


make 
DT_SCHEMA_FILES=Documentation/devicetree/bindings/usb/microchip,usb5744.yaml 
dt_binding_check
   DTEX    Documentation/devicetree/bindings/usb/microchip,usb5744.example.dts
   LINT    Documentation/devicetree/bindings
   CHKDT   Documentation/devicetree/bindings/processed-schema.json
   SCHEMA  Documentation/devicetree/bindings/processed-schema.json
   DTC_CHK Documentation/devicetree/bindings/usb/microchip,usb5744.example.dtb
/home/monstr/data/disk/linux/Documentation/devicetree/bindings/usb/microchip,usb5744.example.dtb: 
hub@1: 'i2c-bus', 'peer-hub', 'reset-gpios' do not match any of the regexes: 
'pinctrl-[0-9]+'
	From schema: 
/home/monstr/data/disk/linux/Documentation/devicetree/bindings/usb/microchip,usb5744.yaml
/home/monstr/data/disk/linux/Documentation/devicetree/bindings/usb/microchip,usb5744.example.dtb: 
hub@2: 'i2c-bus', 'peer-hub', 'reset-gpios' do not match any of the regexes: 
'pinctrl-[0-9]+'
	From schema: 
/home/monstr/data/disk/linux/Documentation/devicetree/bindings/usb/microchip,usb5744.yaml

And this is even without usb-device.yaml wired.

Thanks,
Michal