1PARPORT_WAIT_PERIPHE(9)      Parallel Port Devices     PARPORT_WAIT_PERIPHE(9)
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NAME

6       parport_wait_peripheral - wait for status lines to change in 35ms
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SYNOPSIS

9       int parport_wait_peripheral(struct parport * port, unsigned char mask,
10                                   unsigned char result);
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ARGUMENTS

13       port
14           port to watch
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16       mask
17           status lines to watch
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19       result
20           desired values of chosen status lines
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DESCRIPTION

23       This function waits until the masked status lines have the desired
24       values, or until 35ms have elapsed (see IEEE 1284-1994 page 24 to 25
25       for why this value in particular is hardcoded). The mask and result
26       parameters are bitmasks, with the bits defined by the constants in
27       parport.h: PARPORT_STATUS_BUSY, and so on.
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29       The port is polled quickly to start off with, in anticipation of a fast
30       response from the peripheral. This fast polling time is configurable
31       (using /proc), and defaults to 500usec. If the timeout for this port
32       (see parport_set_timeout) is zero, the fast polling time is 35ms, and
33       this function does not call schedule.
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35       If the timeout for this port is non-zero, after the fast polling fails
36       it uses parport_wait_event to wait for up to 10ms, waking up if an
37       interrupt occurs.
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40Kernel Hackers Manual 3.10         June 2019           PARPORT_WAIT_PERIPHE(9)
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