[V8 PATCH 1/3] ACPICA: Add ACPI _CLS processing

[Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>]

ACPI Device configuration often contain _CLS object to suppy PCI-defined
class code for the device. This patch introduces logic to process the _CLS
object.

Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
---
 drivers/acpi/acpica/acutils.h  |  3 ++
 drivers/acpi/acpica/nsxfname.c | 21 ++++++++++--
 drivers/acpi/acpica/utids.c    | 73 ++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 95 insertions(+), 2 deletions(-)

diff --git a/drivers/acpi/acpica/acutils.h b/drivers/acpi/acpica/acutils.h
index c2f03e8..2aef850 100644
--- a/drivers/acpi/acpica/acutils.h
+++ b/drivers/acpi/acpica/acutils.h
@@ -430,6 +430,9 @@ acpi_status
 acpi_ut_execute_CID(struct acpi_namespace_node *device_node,
 		    struct acpi_pnp_device_id_list ** return_cid_list);
 
+acpi_status
+acpi_ut_execute_CLS(struct acpi_namespace_node *device_node,
+		    struct acpi_pnp_device_id **return_id);
 /*
  * utlock - reader/writer locks
  */
diff --git a/drivers/acpi/acpica/nsxfname.c b/drivers/acpi/acpica/nsxfname.c
index d66c326..590ef06 100644
--- a/drivers/acpi/acpica/nsxfname.c
+++ b/drivers/acpi/acpica/nsxfname.c
@@ -276,11 +276,12 @@ acpi_get_object_info(acpi_handle handle,
 	struct acpi_pnp_device_id *hid = NULL;
 	struct acpi_pnp_device_id *uid = NULL;
 	struct acpi_pnp_device_id *sub = NULL;
+	struct acpi_pnp_device_id *cls = NULL;
 	char *next_id_string;
 	acpi_object_type type;
 	acpi_name name;
 	u8 param_count = 0;
-	u8 valid = 0;
+	u16 valid = 0;
 	u32 info_size;
 	u32 i;
 	acpi_status status;
@@ -320,7 +321,7 @@ acpi_get_object_info(acpi_handle handle,
 	if ((type == ACPI_TYPE_DEVICE) || (type == ACPI_TYPE_PROCESSOR)) {
 		/*
 		 * Get extra info for ACPI Device/Processor objects only:
-		 * Run the Device _HID, _UID, _SUB, and _CID methods.
+		 * Run the Device _HID, _UID, _SUB, _CID and _CLS methods.
 		 *
 		 * Note: none of these methods are required, so they may or may
 		 * not be present for this device. The Info->Valid bitfield is used
@@ -351,6 +352,14 @@ acpi_get_object_info(acpi_handle handle,
 			valid |= ACPI_VALID_SUB;
 		}
 
+		/* Execute the Device._CLS method */
+
+		status = acpi_ut_execute_CLS(node, &cls);
+		if (ACPI_SUCCESS(status)) {
+			info_size += cls->length;
+			valid |= ACPI_VALID_CLS;
+		}
+
 		/* Execute the Device._CID method */
 
 		status = acpi_ut_execute_CID(node, &cid_list);
@@ -468,6 +477,11 @@ acpi_get_object_info(acpi_handle handle,
 							sub, next_id_string);
 	}
 
+	if (cls) {
+		next_id_string = acpi_ns_copy_device_id(&info->cls,
+							cls, next_id_string);
+	}
+
 	if (cid_list) {
 		info->compatible_id_list.count = cid_list->count;
 		info->compatible_id_list.list_size = cid_list->list_size;
@@ -507,6 +521,9 @@ cleanup:
 	if (sub) {
 		ACPI_FREE(sub);
 	}
+	if (cls) {
+		ACPI_FREE(cls);
+	}
 	if (cid_list) {
 		ACPI_FREE(cid_list);
 	}
diff --git a/drivers/acpi/acpica/utids.c b/drivers/acpi/acpica/utids.c
index 27431cf..9745065 100644
--- a/drivers/acpi/acpica/utids.c
+++ b/drivers/acpi/acpica/utids.c
@@ -416,3 +416,76 @@ cleanup:
 	acpi_ut_remove_reference(obj_desc);
 	return_ACPI_STATUS(status);
 }
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ut_execute_CLS
+ *
+ * PARAMETERS:  device_node         - Node for the device
+ *              return_id           - Where the string UID is returned
+ *
+ * RETURN:      Status
+ *
+ * DESCRIPTION: Executes the _CLS control method that returns PCI-defined
+ *              class code of the device. The ACPI spec define _CLS as a
+ *              package with three integers. The returned string has format:
+ *
+ *                      "bbsspp"
+ *              where:
+ *                  bb = Base-class code
+ *                  ss = Sub-class code
+ *                  pp = Programming Interface code
+ *
+ ******************************************************************************/
+
+acpi_status
+acpi_ut_execute_CLS(struct acpi_namespace_node *device_node,
+		    struct acpi_pnp_device_id **return_id)
+{
+	struct acpi_pnp_device_id *cls;
+	union acpi_operand_object *obj_desc;
+	union acpi_operand_object **cls_objects;
+	acpi_status status;
+
+	ACPI_FUNCTION_TRACE(ut_execute_CLS);
+	status = acpi_ut_evaluate_object(device_node, METHOD_NAME__CLS,
+					 ACPI_BTYPE_PACKAGE, &obj_desc);
+	if (ACPI_FAILURE(status))
+		return_ACPI_STATUS(status);
+
+	cls_objects = obj_desc->package.elements;
+
+	if (obj_desc->common.type == ACPI_TYPE_PACKAGE &&
+	    obj_desc->package.count == 3 &&
+	    cls_objects[0]->common.type == ACPI_TYPE_INTEGER &&
+	    cls_objects[1]->common.type == ACPI_TYPE_INTEGER &&
+	    cls_objects[2]->common.type == ACPI_TYPE_INTEGER) {
+
+		/* Allocate a buffer for the CLS */
+		cls = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_pnp_device_id) +
+					 (acpi_size) 7);
+		if (!cls) {
+			status = AE_NO_MEMORY;
+			goto cleanup;
+		}
+
+		cls->string =
+		    ACPI_ADD_PTR(char, cls, sizeof(struct acpi_pnp_device_id));
+
+		sprintf(cls->string, "%02x%02x%02x",
+			(u8)ACPI_TO_INTEGER(cls_objects[0]->integer.value),
+			(u8)ACPI_TO_INTEGER(cls_objects[1]->integer.value),
+			(u8)ACPI_TO_INTEGER(cls_objects[2]->integer.value));
+		cls->length = 7;
+		*return_id = cls;
+	} else {
+		status = AE_AML_OPERAND_TYPE;
+	}
+
+cleanup:
+
+	/* On exit, we must delete the return object */
+
+	acpi_ut_remove_reference(obj_desc);
+	return_ACPI_STATUS(status);
+}
-- 
2.1.0