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diff --git a/Documentation/usb/error-codes.txt b/Documentation/usb/error-codes.txt
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+Revised: 2004-Oct-21
+
+This is the documentation of (hopefully) all possible error codes (and
+their interpretation) that can be returned from usbcore.
+
+Some of them are returned by the Host Controller Drivers (HCDs), which
+device drivers only see through usbcore.  As a rule, all the HCDs should
+behave the same except for transfer speed dependent behaviors and the
+way certain faults are reported.
+
+
+**************************************************************************
+*                   Error codes returned by usb_submit_urb               *
+**************************************************************************
+
+Non-USB-specific:
+
+0		URB submission went fine
+
+-ENOMEM		no memory for allocation of internal structures	
+
+USB-specific:
+
+-EBUSY		The URB is already active.
+
+-ENODEV		specified USB-device or bus doesn't exist
+
+-ENOENT		specified interface or endpoint does not exist or
+		is not enabled
+
+-ENXIO		host controller driver does not support queuing of this type
+		of urb.  (treat as a host controller bug.)
+
+-EINVAL		a) Invalid transfer type specified (or not supported)
+		b) Invalid or unsupported periodic transfer interval
+		c) ISO: attempted to change transfer interval
+		d) ISO: number_of_packets is < 0
+		e) various other cases
+
+-EXDEV		ISO: URB_ISO_ASAP wasn't specified and all the frames
+		the URB would be scheduled in have already expired.
+
+-EFBIG		Host controller driver can't schedule that many ISO frames.
+
+-EPIPE		The pipe type specified in the URB doesn't match the
+		endpoint's actual type.
+
+-EMSGSIZE	(a) endpoint maxpacket size is zero; it is not usable
+		    in the current interface altsetting.
+		(b) ISO packet is larger than the endpoint maxpacket.
+		(c) requested data transfer length is invalid: negative
+		    or too large for the host controller.
+
+-ENOSPC		This request would overcommit the usb bandwidth reserved
+		for periodic transfers (interrupt, isochronous).
+
+-ESHUTDOWN	The device or host controller has been disabled due to some
+		problem that could not be worked around.
+
+-EPERM		Submission failed because urb->reject was set.
+
+-EHOSTUNREACH	URB was rejected because the device is suspended.
+
+-ENOEXEC	A control URB doesn't contain a Setup packet.
+
+
+**************************************************************************
+*                   Error codes returned by in urb->status               *
+*                   or in iso_frame_desc[n].status (for ISO)             *
+**************************************************************************
+
+USB device drivers may only test urb status values in completion handlers.
+This is because otherwise there would be a race between HCDs updating
+these values on one CPU, and device drivers testing them on another CPU.
+
+A transfer's actual_length may be positive even when an error has been
+reported.  That's because transfers often involve several packets, so that
+one or more packets could finish before an error stops further endpoint I/O.
+
+For isochronous URBs, the urb status value is non-zero only if the URB is
+unlinked, the device is removed, the host controller is disabled, or the total
+transferred length is less than the requested length and the URB_SHORT_NOT_OK
+flag is set.  Completion handlers for isochronous URBs should only see
+urb->status set to zero, -ENOENT, -ECONNRESET, -ESHUTDOWN, or -EREMOTEIO.
+Individual frame descriptor status fields may report more status codes.
+
+
+0			Transfer completed successfully
+
+-ENOENT			URB was synchronously unlinked by usb_unlink_urb
+
+-EINPROGRESS		URB still pending, no results yet
+			(That is, if drivers see this it's a bug.)
+
+-EPROTO (*, **)		a) bitstuff error
+			b) no response packet received within the
+			   prescribed bus turn-around time
+			c) unknown USB error 
+
+-EILSEQ (*, **)		a) CRC mismatch
+			b) no response packet received within the
+			   prescribed bus turn-around time
+			c) unknown USB error 
+
+			Note that often the controller hardware does not
+			distinguish among cases a), b), and c), so a
+			driver cannot tell whether there was a protocol
+			error, a failure to respond (often caused by
+			device disconnect), or some other fault.
+
+-ETIME (**)		No response packet received within the prescribed
+			bus turn-around time.  This error may instead be
+			reported as -EPROTO or -EILSEQ.
+
+-ETIMEDOUT		Synchronous USB message functions use this code
+			to indicate timeout expired before the transfer
+			completed, and no other error was reported by HC.
+
+-EPIPE (**)		Endpoint stalled.  For non-control endpoints,
+			reset this status with usb_clear_halt().
+
+-ECOMM			During an IN transfer, the host controller
+			received data from an endpoint faster than it
+			could be written to system memory
+
+-ENOSR			During an OUT transfer, the host controller
+			could not retrieve data from system memory fast
+			enough to keep up with the USB data rate
+
+-EOVERFLOW (*)		The amount of data returned by the endpoint was
+			greater than either the max packet size of the
+			endpoint or the remaining buffer size.  "Babble".
+
+-EREMOTEIO		The data read from the endpoint did not fill the
+			specified buffer, and URB_SHORT_NOT_OK was set in
+			urb->transfer_flags.
+
+-ENODEV			Device was removed.  Often preceded by a burst of
+			other errors, since the hub driver doesn't detect
+			device removal events immediately.
+
+-EXDEV			ISO transfer only partially completed
+			(only set in iso_frame_desc[n].status, not urb->status)
+
+-EINVAL			ISO madness, if this happens: Log off and go home
+
+-ECONNRESET		URB was asynchronously unlinked by usb_unlink_urb
+
+-ESHUTDOWN		The device or host controller has been disabled due
+			to some problem that could not be worked around,
+			such as a physical disconnect.
+
+
+(*) Error codes like -EPROTO, -EILSEQ and -EOVERFLOW normally indicate
+hardware problems such as bad devices (including firmware) or cables.
+
+(**) This is also one of several codes that different kinds of host
+controller use to indicate a transfer has failed because of device
+disconnect.  In the interval before the hub driver starts disconnect
+processing, devices may receive such fault reports for every request.
+
+
+
+**************************************************************************
+*              Error codes returned by usbcore-functions                 *
+*           (expect also other submit and transfer status codes)         *
+**************************************************************************
+
+usb_register():
+-EINVAL			error during registering new driver
+
+usb_get_*/usb_set_*():
+usb_control_msg():
+usb_bulk_msg():
+-ETIMEDOUT		Timeout expired before the transfer completed.