ACPICA: Return object repair: Add resource template repairs

Fixes several possible problems with resource templates returned
by _CRS/_PRS/_DMA predefined names. Lv Zheng.

Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

3 files changed, 99 insertions, 0 deletions

diff --git a/drivers/acpi/acpica/acnamesp.h b/drivers/acpi/acpica/acnamesp.h
index b6ee5192f2ae..6475962a7f2d 100644
--- a/drivers/acpi/acpica/acnamesp.h
+++ b/drivers/acpi/acpica/acnamesp.h
@@ -185,6 +185,10 @@ acpi_status
 acpi_ns_convert_to_unicode(union acpi_operand_object *original_object,
                            union acpi_operand_object **return_object);
 
+acpi_status
+acpi_ns_convert_to_resource(union acpi_operand_object *original_object,
+                            union acpi_operand_object **return_object);
+
 /*
  * nsdump - Namespace dump/print utilities
  */
diff --git a/drivers/acpi/acpica/nsconvert.c b/drivers/acpi/acpica/nsconvert.c
index 84f66994256f..8f79a9d2d50e 100644
--- a/drivers/acpi/acpica/nsconvert.c
+++ b/drivers/acpi/acpica/nsconvert.c
@@ -364,3 +364,80 @@ acpi_ns_convert_to_unicode(union acpi_operand_object *original_object,
         *return_object = new_object;
         return (AE_OK);
 }
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ns_convert_to_resource
+ *
+ * PARAMETERS:  original_object     - Object to be converted
+ *              return_object       - Where the new converted object is returned
+ *
+ * RETURN:      Status. AE_OK if conversion was successful
+ *
+ * DESCRIPTION: Attempt to convert a Integer object to a resource_template
+ *              Buffer.
+ *
+ ******************************************************************************/
+
+acpi_status
+acpi_ns_convert_to_resource(union acpi_operand_object *original_object,
+                            union acpi_operand_object **return_object)
+{
+        union acpi_operand_object *new_object;
+        u8 *buffer;
+
+        /*
+         * We can fix the following cases for an expected resource template:
+         * 1. No return value (interpreter slack mode is disabled)
+         * 2. A "Return (Zero)" statement
+         * 3. A "Return empty buffer" statement
+         *
+         * We will return a buffer containing a single end_tag
+         * resource descriptor.
+         */
+        if (original_object) {
+                switch (original_object->common.type) {
+                case ACPI_TYPE_INTEGER:
+
+                        /* We can only repair an Integer==0 */
+
+                        if (original_object->integer.value) {
+                                return (AE_AML_OPERAND_TYPE);
+                        }
+                        break;
+
+                case ACPI_TYPE_BUFFER:
+
+                        if (original_object->buffer.length) {
+
+                                /* Additional checks can be added in the future */
+
+                                *return_object = NULL;
+                                return (AE_OK);
+                        }
+                        break;
+
+                case ACPI_TYPE_STRING:
+                default:
+
+                        return (AE_AML_OPERAND_TYPE);
+                }
+        }
+
+        /* Create the new buffer object for the resource descriptor */
+
+        new_object = acpi_ut_create_buffer_object(2);
+        if (!new_object) {
+                return (AE_NO_MEMORY);
+        }
+
+        buffer = ACPI_CAST_PTR(u8, new_object->buffer.pointer);
+
+        /* Initialize the Buffer with a single end_tag descriptor */
+
+        buffer[0] = (ACPI_RESOURCE_NAME_END_TAG | ASL_RDESC_END_TAG_SIZE);
+        buffer[1] = 0x00;
+
+        *return_object = new_object;
+        return (AE_OK);
+}
diff --git a/drivers/acpi/acpica/nsrepair.c b/drivers/acpi/acpica/nsrepair.c
index a1918fdf92f2..18f02e4ece01 100644
--- a/drivers/acpi/acpica/nsrepair.c
+++ b/drivers/acpi/acpica/nsrepair.c
@@ -98,6 +98,24 @@ static const struct acpi_simple_repair_info *acpi_ns_match_simple_repair(struct
  * 2nd argument: Unexpected types that can be repaired
  */
 static const struct acpi_simple_repair_info acpi_object_repair_info[] = {
+        /* Resource descriptor conversions */
+
+        {"_CRS",
+         ACPI_RTYPE_INTEGER | ACPI_RTYPE_STRING | ACPI_RTYPE_BUFFER |
+         ACPI_RTYPE_NONE,
+         ACPI_NOT_PACKAGE_ELEMENT,
+         acpi_ns_convert_to_resource},
+        {"_DMA",
+         ACPI_RTYPE_INTEGER | ACPI_RTYPE_STRING | ACPI_RTYPE_BUFFER |
+         ACPI_RTYPE_NONE,
+         ACPI_NOT_PACKAGE_ELEMENT,
+         acpi_ns_convert_to_resource},
+        {"_PRS",
+         ACPI_RTYPE_INTEGER | ACPI_RTYPE_STRING | ACPI_RTYPE_BUFFER |
+         ACPI_RTYPE_NONE,
+         ACPI_NOT_PACKAGE_ELEMENT,
+         acpi_ns_convert_to_resource},
+
         /* Unicode conversions */
 
         {"_MLS", ACPI_RTYPE_STRING, 1,