HAL_USBPortDevice (changes)

Showing changes from revision #3 to #4: Added | Removed | Changed

Hardware Abstraction Layer

HAL entry points from RISC OS

» HAL_USBPortDevice

HAL_USBPortDevice

(HAL entry #120) #112)

int HAL_USBPortDevice(int bus, int port)

Use

This is an internal call for OS use only and should not be used by user software.

Returns device number corresponding to the overcurrent sense circuitry for a single port. A device number refers to the IRQ device number for interrupt calls.

The device number may be shared across several ports (denoted by bit 31 of the device number being set) in the case where, for example, the overcurrent sense lines are wired to a GPIO controller that has only one interrupt output for all its input pins. The HAL_USBPortIRQStatus entry point must be used to determine whether the line is interrupting when deciding whether to claim the respective device vector, or pass it on.

Flag bit 1 of the flags returned by HAL_USBControllerInfo denotes whether the HAL understands how the root hub is wired on the circuit board, if that bit is clear then HAL_USBPortDevice, HAL_USBPortIRQClear and HAL_USBPortIRQStatus are not implemented and an HCI generic means of monitoring the root hub ports must be used as a fallback.

The bus referred to is the same as the one used to enumerate via HAL_USBControllerInfo.

See also

Information source: HWSupport.USB.NetBSD.build.c.ohcimodule in CVS