On 12/19/19 9:05 PM, Thierry Reding wrote: > On Wed, Dec 18, 2019 at 02:46:14PM +0530, Nagarjuna Kristam wrote: >> Add usb-role-switch property for Tegra210 and Tegra186 platforms. This >> entry is used by XUSB pad controller driver to register for role changes >> for OTG/Peripheral capable USB 2 ports. >> >> Signed-off-by: Nagarjuna Kristam <nkristam@xxxxxxxxxx> >> --- >> V2: >> - Moved usb-role-switch to seperate Required section as suggested by Thierry. >> - Added reference to usb/usb-conn-gpio.txt for connector subnode. >> --- >> .../devicetree/bindings/phy/nvidia,tegra124-xusb-padctl.txt | 6 ++++++ >> 1 file changed, 6 insertions(+) >> >> diff --git a/Documentation/devicetree/bindings/phy/nvidia,tegra124-xusb-padctl.txt b/Documentation/devicetree/bindings/phy/nvidia,tegra124-xusb-padctl.txt >> index 9fb682e..23bf354 100644 >> --- a/Documentation/devicetree/bindings/phy/nvidia,tegra124-xusb-padctl.txt >> +++ b/Documentation/devicetree/bindings/phy/nvidia,tegra124-xusb-padctl.txt >> @@ -174,6 +174,12 @@ Required properties: >> - "device": for USB device mode >> - "otg": for USB OTG mode >> >> +Required properties for OTG/Peripheral capable USB2 ports: >> +- usb-role-switch: Boolean property to indicate that the port support OTG or > > "supports", and also, why if it supports OTG *or* peripheral? Doesn't > OTG imply peripheral? OTG means it can be either peripheral or host, > right? So I think the end of that sentence can be just: > > "... the port supports OTG." An USB OTG port is capable of both USB host and peripheral operations. An USB peripheral port can only act as an USB peripheral. The micro USB ports found on Jetson TX1/TX2 platforms are micro-AB ports which should implement both host and peripheral capabilities. We say such ports support OTG. The micro USB port found on Jetson Nano is a micro-B port which should implement peripheral capability only. We say such ports support peripheral, rather than OTG. Thanks, JC > > Otherwise: > > Acked-by: Thierry Reding <treding@xxxxxxxxxx> >
