arm/dt: add basic usb nodes to tegra device trees

For now they are a minimal binding. It needs to be amended with
vendor-specific settings for phy setup and link tuning, etc.

v2: Added bindings specification and phy_type properties

Signed-off-by: Olof Johansson <olof@lixom.net>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Stephen Warren <swarren@nvidia.com>

1 files changed, 13 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/usb/tegra-usb.txt b/Documentation/devicetree/bindings/usb/tegra-usb.txt
new file mode 100644
index 000000000000..035d63d5646d
--- /dev/null
+++ b/Documentation/devicetree/bindings/usb/tegra-usb.txt
@@ -0,0 +1,13 @@
+Tegra SOC USB controllers
+
+The device node for a USB controller that is part of a Tegra
+SOC is as described in the document "Open Firmware Recommended
+Practice : Universal Serial Bus" with the following modifications
+and additions :
+
+Required properties :
+ - compatible : Should be "nvidia,tegra20-ehci" for USB controllers
+   used in host mode.
+ - phy_type : Should be one of "ulpi" or "utmi".
+ - nvidia,vbus-gpio : If present, specifies a gpio that needs to be
+   activated for the bus to be powered.