Re: [PATCH 2/3] arm64: dts: qcom: sa8295p: Enable tertiary controller and its 4 USB ports

From: Krishna Kurapati PSSNV
Date: Wed Feb 07 2024 - 21:40:35 EST




On 2/6/2024 6:54 PM, Dmitry Baryshkov wrote:
On Tue, 6 Feb 2024 at 14:28, Krishna Kurapati PSSNV
<quic_kriskura@xxxxxxxxxxx> wrote:



On 2/6/2024 5:43 PM, Dmitry Baryshkov wrote:
On Tue, 6 Feb 2024 at 14:03, Krishna Kurapati <quic_kriskura@xxxxxxxxxxx> wrote:

Enable tertiary controller for SA8295P (based on SC8280XP).
Add pinctrl support for usb ports to provide VBUS to connected peripherals.

These are not just pinctrl entries. They hide VBUS regulators. Please
implement them properly as corresponding vbus regulators.


Hi Dmitry. Apologies, can you elaborate on your comment. I thought this
implementation was fine as Konrad reviewed it in v13 [1]. I removed his
RB tag as I made one change of dropping "_state" in labels.

My comment is pretty simple: if I'm not mistaken, your DT doesn't
reflect your hardware design.
You have actual VBUS regulators driven by these GPIO pins. Is this correct?
If so, you should describe them properly in the device tree rather
than describing them just as USB host's pinctrl state.


Hi Dmitry,

I have very little idea about the gpio controller regulators. I will go through it and see how I can implement it. I just found this : https://www.kernel.org/doc/Documentation/devicetree/bindings/regulator/gpio-regulator.txt

One query. If we model it as a regulator, do we need to add it as a supply and call regulator_enable in dwc3_qcom probe again ?

Regards,
Krishna,