aboutsummaryrefslogtreecommitdiffstats
path: root/Documentation/devicetree/bindings/usb/nvidia,tegra20-ehci.txt
diff options
context:
space:
mode:
Diffstat (limited to 'Documentation/devicetree/bindings/usb/nvidia,tegra20-ehci.txt')
-rw-r--r--Documentation/devicetree/bindings/usb/nvidia,tegra20-ehci.txt29
1 files changed, 29 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/usb/nvidia,tegra20-ehci.txt b/Documentation/devicetree/bindings/usb/nvidia,tegra20-ehci.txt
new file mode 100644
index 0000000..e9b005d
--- /dev/null
+++ b/Documentation/devicetree/bindings/usb/nvidia,tegra20-ehci.txt
@@ -0,0 +1,29 @@
+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.
+
+Required properties for phy_type == ulpi:
+ - nvidia,phy-reset-gpio : The GPIO used to reset the PHY.
+
+Optional properties:
+ - dr_mode : dual role mode. Indicates the working mode for
+ nvidia,tegra20-ehci compatible controllers. Can be "host", "peripheral",
+ or "otg". Default to "host" if not defined for backward compatibility.
+ host means this is a host controller
+ peripheral means it is device controller
+ otg means it can operate as either ("on the go")
+ - nvidia,has-legacy-mode : boolean indicates whether this controller can
+ operate in legacy mode (as APX 2500 / 2600). In legacy mode some
+ registers are accessed through the APB_MISC base address instead of
+ the USB controller. Since this is a legacy issue it probably does not
+ warrant a compatible string of its own.