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USB_GET_STATUS(9) USB Core APIs 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 0 and the status value in * data (in host byte order) on success, or else the status code from the underlying usb_control_msg call.

COPYRIGHT

January 2017 Kernel Hackers Manual 4.8.