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

6       parport_yield - relinquish a parallel port temporarily
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SYNOPSIS

9       int parport_yield(struct pardevice * dev);
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ARGUMENTS

12       dev
13           a device on the parallel port
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DESCRIPTION

16       This function relinquishes the port if it would be helpful to other
17       drivers to do so. Afterwards it tries to reclaim the port using
18       parport_claim, and the return value is the same as for parport_claim.
19       If it fails, the port is left unclaimed and it is the driver's
20       responsibility to reclaim the port.
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22       The parport_yield and parport_yield_blocking functions are for marking
23       points in the driver at which other drivers may claim the port and use
24       their devices. Yielding the port is similar to releasing it and
25       reclaiming it, but is more efficient because no action is taken if
26       there are no other devices needing the port. In fact, nothing is done
27       even if there are other devices waiting but the current device is still
28       within its “timeslice”. The default timeslice is half a second, but it
29       can be adjusted via the /proc interface.
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32Kernel Hackers Manual 2.6.       November 2011                PARPORT_YIELD(9)
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