Re: [PATCH 1/3] dt-bindings: usb: qcom,dwc3: Add multi-pd bindings for dwc3 qcom

Rajendra Nayak
2021-09-07T12:20:40Z

On 9/6/2021 2:45 PM, Sandeep Maheswaram wrote:
>
> On 8/31/2021 1:37 AM, Doug Anderson wrote:
>> Hi,
>>
>> On Mon, Aug 30, 2021 at 10:55 AM Sandeep Maheswaram <sanm@codeaurora.org> wrote:
>>> Add multi pd bindings to set performance state for cx domain
>>> to maintain minimum corner voltage for USB clocks.
>>>
>>> Signed-off-by: Sandeep Maheswaram <sanm@codeaurora.org>
>>> ---
>>>   Documentation/devicetree/bindings/usb/qcom,dwc3.yaml | 13 ++++++++++++-
>>>   1 file changed, 12 insertions(+), 1 deletion(-)
>>>
>>> diff --git a/Documentation/devicetree/bindings/usb/qcom,dwc3.yaml b/Documentation/devicetree/bindings/usb/qcom,dwc3.yaml
>>> index e70afc4..838d9c4 100644
>>> --- a/Documentation/devicetree/bindings/usb/qcom,dwc3.yaml
>>> +++ b/Documentation/devicetree/bindings/usb/qcom,dwc3.yaml
>>> @@ -41,7 +41,18 @@ properties:
>>>
>>>     power-domains:
>>>       description: specifies a phandle to PM domain provider node
>>> -    maxItems: 1
>>> +    minItems: 1
>>> +    items:
>>> +      - description: optional,cx power domain
>>> +      - description: USB gdsc power domain
>> You need to re-order the above. The optional one needs to be second, not first.
>>
> I wanted to use required-opps for cx domain only. so I have put it first in order.

You can always put a <> for the power-domains for which there are no required-opps

+ power-domain-names = "usb_gdsc", "cx";
+
+ required-opps = <>, <&rpmhpd_opp_nom>;

>>> +  power-domain-names:
>>> +     items:
>>> +      - const: cx
>>> +      - const: usb_gdsc
>> Why do you need the names at all? The ordering of power-domains is
>> well defined and there are no holes in it and there are no legacy
>> reasons for having the names (like there are for clocks), so you
>> should drop. This is much like reg-names and I always point people to
>> this message from Rob Herring about reg-names:
>>
>> https://lore.kernel.org/r/CAL_Jsq+MMunmVWqeW9v2RyzsMKP+=kMzeTHNMG4JDHM7Fy0HBg@mail.gmail.com/
>>
>> You'll have to change your driver to use dev_pm_domain_attach_by_id()
>> but that should be fine.
>>
>> -Doug
>
> Ok..I will try using  dev_pm_domain_attach_by_id()