Re: [RESEND v4 1/2] dt-bindings: imx6q-pcie: add one regulator used to power up pcie phy

From: Bjorn Helgaas
Date: Thu May 06 2021 - 17:01:24 EST


On Thu, May 06, 2021 at 06:08:24PM +0200, Lucas Stach wrote:
> Hi Lorenzo,
>
> have those two patches fallen through some crack? AFAICS they are gone
> from patchwork, but I also can't find them in any branch in the usual
> git repos.

They were marked "accepted" in patchwork but must have fallen through
the cracks. I reset them to "new" and assigned to Lorenzo.

Neither one follows the subject line capitalization conventions.

The subject line of this patch (1/2) doesn't really make sense. I
*think* this adds a property ("vph-supply") to indicate which
regulator supplys power to the PHY.

> Am Dienstag, dem 30.03.2021 um 16:08 +0800 schrieb Richard Zhu:
> > Both 1.8v and 3.3v power supplies can be used by i.MX8MQ PCIe PHY.
> > In default, the PCIE_VPH voltage is suggested to be 1.8v refer to data
> > sheet. When PCIE_VPH is supplied by 3.3v in the HW schematic design,
> > the VREG_BYPASS bits of GPR registers should be cleared from default
> > value 1b'1 to 1b'0. Thus, the internal 3v3 to 1v8 translator would be
> > turned on.

This commit log doesn't describe the patch, either. Maybe something
like this:

dt-bindings: imx6q-pcie: Add "vph-supply" for PHY supply voltage

The i.MX8MQ PCIe PHY can use either a 1.8V or a 3.3V power supply.
Add a "vph-supply" property to indicate which regulator supplies
power for the PHY.

> > Signed-off-by: Richard Zhu <hongxing.zhu@xxxxxxx>
> > Reviewed-by: Lucas Stach <l.stach@xxxxxxxxxxxxxx>
> > ---
> >  Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.txt | 3 +++
> >  1 file changed, 3 insertions(+)
> >
> > diff --git a/Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.txt b/Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.txt
> > index de4b2baf91e8..d8971ab99274 100644
> > --- a/Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.txt
> > +++ b/Documentation/devicetree/bindings/pci/fsl,imx6q-pcie.txt
> > @@ -38,6 +38,9 @@ Optional properties:
> >    The regulator will be enabled when initializing the PCIe host and
> >    disabled either as part of the init process or when shutting down the
> >    host.
> > +- vph-supply: Should specify the regulator in charge of VPH one of the three
> > + PCIe PHY powers. This regulator can be supplied by both 1.8v and 3.3v voltage
> > + supplies.

Just going by examples for other drivers, I think this should say
something like this:

- vph-supply: Regulator for i.MX8MQ PCIe PHY. May supply either
1.8V or 3.3V.

You mentioned "one of the three PCIe PHY powers"; I don't know what
that means, so I don't know whether it's important to include.

I also don't know what "vph" means; if the "ph" is part of "phy", it'd
be nicer to include the "y", so it would be "vphy-supply".

> >  Additional required properties for imx6sx-pcie:
> >  - clock names: Must include the following additional entries: