ACPI: introduce helper interfaces for _DSM method

There are several drivers making use of ACPI _DSM method to detect
and invoke device specific methods. Currently every driver has
implemented its private version to support ACPI _DSM method.
So this patch introduces three helper functions to support ACPI _DSM
method, which will be used to replace open-coded versions.

It helps to simplify code and improve code readability.

Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

1 files changed, 26 insertions, 0 deletions

diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h
index ddabed1f51c2..dd9b5edc7630 100644
--- a/include/acpi/acpi_bus.h
+++ b/include/acpi/acpi_bus.h
@@ -66,6 +66,32 @@ bool acpi_ata_match(acpi_handle handle);
 bool acpi_bay_match(acpi_handle handle);
 bool acpi_dock_match(acpi_handle handle);
 
+bool acpi_check_dsm(acpi_handle handle, const u8 *uuid, int rev, u64 funcs);
+union acpi_object *acpi_evaluate_dsm(acpi_handle handle, const u8 *uuid,
+                        int rev, int func, union acpi_object *argv4);
+
+static inline union acpi_object *
+acpi_evaluate_dsm_typed(acpi_handle handle, const u8 *uuid, int rev, int func,
+                        union acpi_object *argv4, acpi_object_type type)
+{
+        union acpi_object *obj;
+
+        obj = acpi_evaluate_dsm(handle, uuid, rev, func, argv4);
+        if (obj && obj->type != type) {
+                ACPI_FREE(obj);
+                obj = NULL;
+        }
+
+        return obj;
+}
+
+#define ACPI_INIT_DSM_ARGV4(cnt, eles)                  \
+        {                                               \
+          .package.type = ACPI_TYPE_PACKAGE,            \
+          .package.count = (cnt),                       \
+          .package.elements = (eles)                    \
+        }
+
 #ifdef CONFIG_ACPI
 
 #include <linux/proc_fs.h>