Re: [PATCH V5 1/6] dt-bindings: usb: Add NVIDIA Tegra234 XUSB host controller binding

[Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>]

On 09/01/2023 18:00, Jon Hunter wrote:
> 
> On 08/01/2023 15:21, Krzysztof Kozlowski wrote:
> 
> ...
> 
>> On 06/01/2023 16:28, Jon Hunter wrote:
>>> +  phys:
>>> +    minItems: 1
>>> +    maxItems: 8
>>> +
>>> +  phy-names:
>>> +    minItems: 1
>>> +    maxItems: 8
>>> +    items:
>>> +      enum:
>>> +        - usb2-0
>>> +        - usb2-1
>>> +        - usb2-2
>>> +        - usb2-3
>>> +        - usb3-0
>>> +        - usb3-1
>>> +        - usb3-2
>>> +        - usb3-3
>>
>> Why do you have so many optional phys? In what case you would put there
>> usb2-0 and usb3-3 together? Or even 8 phys at the same time? IOW, what
>> are the differences between them and why one controller would be
>> connected once to usb3-2 and once to usb3-3 phy? And once to both?
> 
> 
> Here is the description from the device documentation ...
> 
> "The NVIDIA Orin series System-on-Chip (SoC) has one xHCI host 
> controller and one USB 3.2 Gen1 x1 device controller. The two 
> controllers control a total of up to eight exposed ports. There are up 
> to four USB 2.0 ports and up to four USB 3.2 Gen1 x1 ports."
> 
> So there are eight phys and we could have 4 USB2 and 4 USB3. Depending 
> on which pins you want to use, you could have various combinations. I 
> can add these details to the binding doc if that helps.	

Yeah, could solve some questions.

Best regards,
Krzysztof