ACPI / scan: Fix check of device_attach() return value.

Since device_attach() returns 1 on success (a driver has been bound
to the device), the check against its return value in
acpi_bus_device_attach() should modified to take that into accout.
Make it so.

[rjw: Subject and changelog.]
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
ACPI: remove unused acpi_op_bind and acpi_op_unbind

With commit f2a33cde55a03 "ACPI: Drop ACPI device .bind() and .unbind()
callbacks", acpi_op_bind and acpi_op_unbind are not used any more. So
remove them.

Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
ACPI: Remove the ops field from struct acpi_device

The ops field in struct acpi_device is not used anywhere, so remove
it.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Toshi Kani <toshi.kani@hp.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
ACPI / scan: Drop the second argument of acpi_device_unregister()

Drop the second argument of acpi_device_unregister(), type, which is
not used by that function.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Toshi Kani <toshi.kani@hp.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
ACPI / scan: Drop the second argument of acpi_bus_trim()

All callers of acpi_bus_trim() pass 1 (true) as the second argument
of it, so remove that argument entirely and change acpi_bus_trim()
to always behave as though it were 1.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Toshi Kani <toshi.kani@hp.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
ACPI / scan: Change the implementation of acpi_bus_trim()

The current acpi_bus_trim() implementation is not really
straightforward and may be simplified significantly by using
acpi_walk_namespace() with acpi_bus_remove() as a post-order
callback.

Observe that acpi_bus_remove(), as called by acpi_bus_trim(), cannot
actually fail, because its first argument is guaranteed not to be
NULL thanks to the acpi_bus_get_device() check in acpi_bus_trim(),
so simply move the acpi_bus_get_device() check to acpi_bus_remove()
and use acpi_walk_namespace() to execute it for every device under
start->handle as a post-order callback.  The, run it directly for
start->handle itself.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Toshi Kani <toshi.kani@hp.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
ACPI / scan: Add second pass to acpi_bus_trim()

Make acpi_bus_trim() work in analogy with acpi_bus_scan() and carry
out two passes such that ACPI drivers will be detached from device
nodes being removed in the first pass and the device nodes themselves
will be removed in the second pass.

For this purpose split the driver unregistration out of
acpi_bus_remove() into a new routine, acpi_bus_device_detach(), that
will be executed by acpi_bus_trim() in the additional first pass as
a post-order callback.

This is necessary, because some ACPI drivers' .remove() routines
unregister struct device objects associated with the ACPI device
nodes being removed and that needs to happen while the ACPI
device nodes are still around (for example, in case they need to be
used for power management or similar things at that time).

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Toshi Kani <toshi.kani@hp.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
ACPI: update ej_event interface to take acpi_device

Should use acpi_device pointer directly instead of use handle and
get the device pointer again later.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>