1USB_QUEUE_RESET_DEVI(9)          USB Core APIs         USB_QUEUE_RESET_DEVI(9)
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NAME

6       usb_queue_reset_device - Reset a USB device from an atomic context
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SYNOPSIS

9       void usb_queue_reset_device(struct usb_interface * iface);
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ARGUMENTS

12       iface
13           USB interface belonging to the device to reset
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DESCRIPTION

16       This function can be used to reset a USB device from an atomic context,
17       where usb_reset_device won't work (as it blocks).
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19       Doing a reset via this method is functionally equivalent to calling
20       usb_reset_device, except for the fact that it is delayed to a
21       workqueue. This means that any drivers bound to other interfaces might
22       be unbound, as well as users from usbfs in user space.
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CORNER CASES

25       - Scheduling two resets at the same time from two different drivers
26       attached to two different interfaces of the same device is possible;
27       depending on how the driver attached to each interface handles
28       ->pre_reset, the second reset might happen or not.
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30       - If a driver is unbound and it had a pending reset, the reset will be
31       cancelled.
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33       - This function can be called during .probe or .disconnect times. On
34       return from .disconnect, any pending resets will be cancelled.
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36       There is no no need to lock/unlock the reset_ws as schedule_work does
37       its own.
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NOTE

40       We don't do any reference count tracking because it is not needed. The
41       lifecycle of the work_struct is tied to the usb_interface. Before
42       destroying the interface we cancel the work_struct, so the fact that
43       work_struct is queued and or running means the interface (and thus, the
44       device) exist and are referenced.
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47Kernel Hackers Manual 2.6.       November 2011         USB_QUEUE_RESET_DEVI(9)
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