usb_get_status
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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.

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