usb_get_status(9)
NAME
usb_get_status - issues a GET_STATUS call
SYNOPSIS
int usb_get_status(struct usb_device * dev, int type, int target,
void * data);
ARGUMENTS
- dev
- the device whose status is being checked
- type
- USB_RECIP_*; for device, interface, or endpoint
- target
- zero (for device), else interface or endpoint number
- data
- pointer to two bytes of bitmap data
CONTEXT
!in_interrupt ()
DESCRIPTION
Returns device, interface, or endpoint status. Normally only of
interest to see if the device is self powered, or has enabled the
remote wakeup facility; or whether a bulk or interrupt endpoint is
halted ("stalled").
Bits in these status bitmaps are set using the SET_FEATURE request, and
cleared using the CLEAR_FEATURE request. The usb_clear_halt function
should be used to clear halt ("stall") status.
This call is synchronous, and may not be used in an interrupt context.
Returns the number of bytes received on success, or else the status
code returned by the underlying usb_control_msg call.