• Rafael J. Wysocki's avatar
    ACPI: Make acpi_bus_scan() and acpi_bus_add() take only one argument · 0cd6ac52
    Rafael J. Wysocki authored
    The callers of acpi_bus_add() usually assume that if it has
    succeeded, then a struct acpi_device object has been attached to
    the handle passed as the first argument.  Unfortunately, however,
    this assumption is wrong, because acpi_bus_scan(), and acpi_bus_add()
    too as a result, may return a pointer to a different struct
    acpi_device object on success (it may be an object corresponding to
    one of the descendant ACPI nodes in the namespace scope below that
    handle).
    
    For this reason, the callers of acpi_bus_add() who care about
    whether or not a struct acpi_device object has been created for
    its first argument need to check that using acpi_bus_get_device()
    anyway, so the second argument of acpi_bus_add() is not really
    useful for them.  The same observation applies to acpi_bus_scan()
    executed directly from acpi_scan_init().
    
    Therefore modify the relevant callers of acpi_bus_add() to check the
    existence of the struct acpi_device in question with the help of
    acpi_bus_get_device() and drop the no longer necessary second
    argument of acpi_bus_add().  Accordingly, modify acpi_scan_init() to
    use acpi_bus_get_device() to get acpi_root and drop the no longer
    needed second argument of acpi_bus_scan().
    Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
    Acked-by: default avatarYinghai Lu <yinghai@kernel.org>
    Acked-by: default avatarToshi Kani <toshi.kani@hp.com>
    0cd6ac52
processor_driver.c 25 KB