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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