SPI_BUS_LOCK(9)                   Serial Peripheral Interface (S                  SPI_BUS_LOCK(9)



NAME
       spi_bus_lock - obtain a lock for exclusive SPI bus usage

SYNOPSIS
       int spi_bus_lock(struct spi_master * master);

ARGUMENTS
       master
           SPI bus master that should be locked for exclusive bus access

CONTEXT
       can sleep

DESCRIPTION
       This call may only be used from a context that may sleep. The sleep is non-interruptible,
       and has no timeout.

       This call should be used by drivers that require exclusive access to the SPI bus. The SPI
       bus must be released by a spi_bus_unlock call when the exclusive access is over. Data
       transfer must be done by spi_sync_locked and spi_async_locked calls when the SPI bus lock
       is held.

RETURN
       always zero.

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