Samsung S5PC100, User Manual

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S5PC100 USER’S MANUAL (REV1.0) USB HOST CONTROLLER
8.9-11
Table 8.9-2 UHCCON Bit Definitions
UHCCON Bit Description R/W Reset Value
Reserved [31:11] Reserved -
RWE [10] RemoteWakeupEnable
The host controller driver uses this bit to enable or disable
the remote wakeup feature upon the detection of upstream
resume signaling. If this bit is set and the ResumeDetected
bit in HcInterruptStatus (Refer to Section 20.8.4) is set, a
remote wake-up is signaled to the host system. Setting this
bit has no impact on the generation of hardware interrupt.
0 = Disable remote wake-up is signaling to the host system.
1 = Enable remote wake-up is signaling to the host system. R/W
RWC [9] RemoteWakeupConnected
This bit indicates whether the UHC supports remote wake-
up signaling. If remote wake-up is supported and used by
the system, it is the responsibility of system firmware to set
this bit after reset. The UHC clears the bit upon a hardware
reset, but does not alter it upon a software reset
0 = UHC does not support remote wake-up signaling.
1 = UHC supports remote wake-up signaling. R/W
IR [8] InterruptRouting
This bit determines the routing of interrupts generated by
events registered in the UHC Interrupt Status register,
UHCINTS (Refer to Section 20.8.4). If clear, all interrupts are
routed to the normal host bus-interrupt mechanism. If set,
interrupts are routed to the system management interrupt
(SMI). The host controller driver clears this bit on a hardware
reset, but it does not alter this bit on a software reset. The
host controller driver uses this bit as a tag to indicate the
ownership of UHC. This implementation of the OHCI host
controller does not support SMI. Therefore, the host
controller driver must never set this bit.
0 = All interrupts are routed to the normal host bus interrupt
mechanism.
1 = Interrupts are routed to the SMI. R/W
HCFS [7:6] HostControllerFunctionalState
This field of two bits displays the current functional state of
the USB host controller.
0b00 = USBRESET 0b01 = USBRESUME
0b10 = USBOPERATIONAL 0b11 =
USBSUSPEND
A transition to USBOPERATIONAL from another state
causes an SOF generation to begin 1 ms later. The host
controller driver determines whether UHC has started
sending SOFs by reading the StartofFrame field of
HcInterruptStatus (Refer to Section 20.8.4).
This field is changed by UHC if in the USBSUSPEND state.
UHC moves from the USBSUSPEND state to the
USBRESUME state after detecting the resume signaling
from a downstream port. R/W