[3/8] dt-bindings: phy: tegra-xusb-padctl: Add nvidia,usb3-port-fake entry

[Thierry Reding <thierry.reding@gmail.com>]

On Thu, Jan 03, 2019 at 03:34:54PM +0530, Nagarjuna Kristam wrote:
> Add binding details regarding nvidia,usb3-port-fake
> 
> Signed-off-by: Nagarjuna Kristam <nkristam@nvidia.com>
> ---
>  Documentation/devicetree/bindings/phy/nvidia,tegra124-xusb-padctl.txt | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/phy/nvidia,tegra124-xusb-padctl.txt b/Documentation/devicetree/bindings/phy/nvidia,tegra124-xusb-padctl.txt
> index 3742c15..21a5541 100644
> --- a/Documentation/devicetree/bindings/phy/nvidia,tegra124-xusb-padctl.txt
> +++ b/Documentation/devicetree/bindings/phy/nvidia,tegra124-xusb-padctl.txt
> @@ -158,6 +158,9 @@ Optional properties:
>    is internal. In the absence of this property the port is considered to be
>    external.
>  - vbus-supply: phandle to a regulator supplying the VBUS voltage.
> +- nvidia,usb3-port-fake: A integer property whose presense informs that a
> +  fake USB3 port needs to be mapped for corresponding USB2 port. This entry
> +  is applicable only for Tegra210 based platforms which has USB2 only ports.

You don't provide a rationale fo why this fake USB3 port needs to be
specified. Doesn't the OTG port work without the fake USB3 port? Why
does it need to be specified and which one should be used as fake?

You mention elsewhere that an unused USB3 port is used on Jetson TX1,
but what if there are no unused ports on a platform? Can we use any
USB3 port for this purpose?

Thierry