Cirrus Logic EP93xx - Manual (Page 471)

DS785UM1 11-31
Copyright 2007 Cirrus Logic
Universal Serial Bus Host Controller
EP93xx User’s Guide
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RSVD: Reserved. Unknown During Read.
LPS: (READ) LocalPowerStatus. The Root Hub does not
support the local power status feature; thus, this bit is
always read as “0”.
(WRITE) ClearGlobalPower: In global power mode
(PowerSwitchingMode=0), this bit is written to “1” to turn
off power to all ports (clear PortPowerStatus). In per-port
power mode, it clears PortPowerStatus only on ports
whose PortPowerControlMask bit is not set. Writing a “0”
has no effect.
OCI: OverCurrentIndicator. This bit reports overcurrent
conditions when the global reporting is implemented.
When set, an overcurrent condition exists. When cleared,
all power operations are normal. If per-port overcurrent
protection is implemented this bit is always “0”
DRWE: (READ) DeviceRemoteWakeupEnable. This bit enables a
ConnectStatusChange bit as a resume event, causing a
USBSUSPEND to USBRESUME state transition and
setting the ResumeDetected interrupt.
0 = ConnectStatusChange is not a remote wakeup event.
1 = ConnectStatusChange is a remote wakeup event.
(WRITE) SetRemoteWakeupEnable: Writing a '1' sets
DeviceRemoveWakeupEnable. Writing a '0' has no effect.
LPSC: (READ) LocalPowerStatusChange. The Root Hub does
not support the local power status feature; thus, this bit is
always read as “0”.
(WRITE) SetGlobalPower. In global power mode
(PowerSwitchingMode=0), This bit is written to “1” to turn
on power to all ports (clear PortPowerStatus). In per-port
power mode, it sets PortPowerStatus only on ports whose
PortPowerControlMask bit is not set. Writing a “0” has no
effect.
CCIC: OverCurrentIndicatorChange. This bit is set by hardware
when a change has occurred to the OCI field of this
register. The HCD clears this bit by writing a “1”. Writing a
“0” has no effect.
CRWE: (WRITE) ClearRemoteWakeupEnable. Writing a '1' clears
DeviceRemoveWakeupEnable. Writing a '0' has no effect.