Provided by: linux-doc-2.6.15_2.6.15-23.39_all bug

NAME

       usb_ep_fifo_status - returns number of bytes in fifo, or error

SYNOPSIS

       int usb_ep_fifo_status  (struct usb_ep * ep);

ARGUMENTS

       ep     the endpoint whose fifo status is being checked.

DESCRIPTION

       FIFO  endpoints  may  have ‘‘unclaimed data’’ in them in certain cases,
       such as after aborted transfers. Hosts may not have collected  all  the
       IN  data  written  by  the  gadget  driver  (and  reported by a request
       completion). The gadget driver may not  have  collected  all  the  data
       written  OUT  to it by the host. Drivers that need precise handling for
       fault reporting or recovery may need to use this call.

       This returns the number of such bytes in the fifo, or a negative  errno
       if  the  endpoint  doesn’t  use  a FIFO or doesn’t support such precise
       handling.

AUTHOR

       David Brownell <dbrownell@users.sourceforge.net>.