PARPORT_YIELD(9)                      Parallel Port Devices                      PARPORT_YIELD(9)



NAME
       parport_yield - relinquish a parallel port temporarily

SYNOPSIS
       int parport_yield(struct pardevice * dev);

ARGUMENTS
       dev
           a device on the parallel port

DESCRIPTION
       This function relinquishes the port if it would be helpful to other drivers to do so.
       Afterwards it tries to reclaim the port using parport_claim, and the return value is the
       same as for parport_claim. If it fails, the port is left unclaimed and it is the driver's
       responsibility to reclaim the port.

       The parport_yield and parport_yield_blocking functions are for marking points in the
       driver at which other drivers may claim the port and use their devices. Yielding the port
       is similar to releasing it and reclaiming it, but is more efficient because no action is
       taken if there are no other devices needing the port. In fact, nothing is done even if
       there are other devices waiting but the current device is still within its “timeslice”.
       The default timeslice is half a second, but it can be adjusted via the /proc interface.

COPYRIGHT
Kernel Hackers Manual 4.8.                 January 2017                          PARPORT_YIELD(9)