Re: [PATCHv3 1/6] ARM: dts: meson8b: odroidc1: Add usb phy power node

[Neil Armstrong]

Hi,

On 30/08/2021 21:37, Martin Blumenstingl wrote:
> Hi Neil,
> 
> On Mon, Aug 30, 2021 at 9:45 AM Neil Armstrong <narmstrong@xxxxxxxxxxxx> wrote:
>>
>> Hi,
>>
>> On 17/08/2021 06:15, Anand Moon wrote:
>>> Add missing usb phy power node for usb node fix below warning.
>>> P5V0 regulator supply input voltage range to USB host controller.
>>> As described in the C1+ schematics, GPIO GPIOAO_5 is used to
>>> enable input power to USB ports, set it to Active Low.
>>>
>>> [    1.260772] dwc2 c90c0000.usb: Looking up vbus-supply from device tree
>>> [    1.260784] dwc2 c90c0000.usb: Looking up vbus-supply property in
>>>               mode /soc/usb@c90c0000 failed
>>
>> First of all, DT is not here to fix boot message.
> Anand mentioned elsewhere that this is a debug/info message
> 
>> Finally, I looked at the Odroid-C1 schematics and the GPIOAO.BIT5 is an input
>> to the S805, and the PWREN signal is controlled by the USB Hub so this regulator
>> should not be added at all.
> I think there's a misunderstanding because there's two PWREN signals
> with different meanings.
> The PWREN signal for the USB host ports is hard-wired and not
> connected to the SoC at all.
> The PWREN signal for the Micro-USB port (which Anand is adding here)
> is controlled by GPIOAO_5. odroid-c1+_rev0.4_20150615.pdf [0] shows it
> as an input to "USB_OTG" on page 1. "USB_OTG" consists of a power
> switch and the connector itself as shown on page 28.
> 
> Personally I think that the change from Anand itself is good.
> If you feel otherwise then please speak up.

Ok thanks for the clarification, then the change is ok, but not the commit message.

>> Add missing usb phy power node for usb node fix below warning.

is not a good reason for a DT change. A proper reason should be added.

And the commit message doesn't specify the change is for the Micro-USB port,
this should be clarified.

Neil

> As I pointed out three smaller changes I am hoping that Anand will
> re-send the updated patch anyways. At that point he can also add the
> changes from your feedback.
> 
> 
> Best regards,
> Martin
> 
> 
> [0] https://dn.odroid.com/S805/Schematics/odroid-c1+_rev0.4_20150615.pdf
>