1f3d549ddSStephen WarrenTegra SOC USB controllers
2f3d549ddSStephen Warren
3f3d549ddSStephen WarrenThe device node for a USB controller that is part of a Tegra
4f3d549ddSStephen WarrenSOC is as described in the document "Open Firmware Recommended
5f3d549ddSStephen WarrenPractice : Universal Serial Bus" with the following modifications
6f3d549ddSStephen Warrenand additions :
7f3d549ddSStephen Warren
8f3d549ddSStephen WarrenRequired properties :
9f3d549ddSStephen Warren - compatible : Should be "nvidia,tegra20-ehci" for USB controllers
10f3d549ddSStephen Warren   used in host mode.
11f3d549ddSStephen Warren - phy_type : Should be one of "ulpi" or "utmi".
12f3d549ddSStephen Warren - nvidia,vbus-gpio : If present, specifies a gpio that needs to be
13f3d549ddSStephen Warren   activated for the bus to be powered.
14f3d549ddSStephen Warren
15f3d549ddSStephen WarrenRequired properties for phy_type == ulpi:
16f3d549ddSStephen Warren  - nvidia,phy-reset-gpio : The GPIO used to reset the PHY.
17f3d549ddSStephen Warren
18f3d549ddSStephen WarrenOptional properties:
19f3d549ddSStephen Warren  - dr_mode : dual role mode. Indicates the working mode for
20f3d549ddSStephen Warren   nvidia,tegra20-ehci compatible controllers.  Can be "host", "peripheral",
21f3d549ddSStephen Warren   or "otg".  Default to "host" if not defined for backward compatibility.
22f3d549ddSStephen Warren      host means this is a host controller
23f3d549ddSStephen Warren      peripheral means it is device controller
24f3d549ddSStephen Warren      otg means it can operate as either ("on the go")
25f3d549ddSStephen Warren  - nvidia,has-legacy-mode : boolean indicates whether this controller can
26f3d549ddSStephen Warren    operate in legacy mode (as APX 2500 / 2600). In legacy mode some
27f3d549ddSStephen Warren    registers are accessed through the APB_MISC base address instead of
28f3d549ddSStephen Warren    the USB controller. Since this is a legacy issue it probably does not
29f3d549ddSStephen Warren    warrant a compatible string of its own.
30b4e07478SVenu Byravarasu  - nvidia,needs-double-reset : boolean is to be set for some of the Tegra2
31b4e07478SVenu Byravarasu    USB ports, which need reset twice due to hardware issues.
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