Call directly into acpica to load a table to obtain its index on return.
We choose the direct call of acpica internal functions to avoid having
to modify its API which is used outside of Linux as well.
Use that index to unload the table again when the corresponding
directory in configfs gets removed. This allows to change SSDTs without
rebooting the system. It also allows to destroy devices again that a
dynamically loaded SSDT created.
This is widely similar to the DT overlay behavior.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
If we compile ACPI configfs.c as module it will confuse the linker as it
hides symbols from the actual configfs:
Kernel: arch/x86/boot/bzImage is ready (#1236)
MODPOST 5739 modules
ERROR: "configfs_unregister_subsystem" [samples/configfs/configfs_sample.ko] undefined!
ERROR: "configfs_register_subsystem" [samples/configfs/configfs_sample.ko] undefined!
ERROR: "config_group_init" [samples/configfs/configfs_sample.ko] undefined!
ERROR: "config_item_init_type_name" [samples/configfs/configfs_sample.ko] undefined!
ERROR: "config_group_init_type_name" [samples/configfs/configfs_sample.ko] undefined!
ERROR: "configfs_undepend_item" [fs/ocfs2/cluster/ocfs2_nodemanager.ko] undefined!
...
Prevent these by renaming the file to acpi_configfs.c instead.
Reported-by: Scott Lawson <scott.lawson@intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
