[PATCH 1/3] arm: tegra: dts: Support host/device selection and legacy mode
sjg at chromium.org
Fri Feb 3 11:56:10 EST 2012
Some USB ports can support host and device operation. We add the dr_mode
property (as found in Freescale) for this.
One USB port has a 'legacy mode', left over from the days of pre-Tegra
chips. I don't believe this is actually used, except that we must know
to turn this off in the driver.
Signed-off-by: Simon Glass <sjg at chromium.org>
.../devicetree/bindings/usb/tegra-usb.txt | 13 +++++++++++++
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
index 035d63d..007005d 100644
@@ -11,3 +11,16 @@ Required properties :
- 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.
+ - 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.
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