1 files changed, 29 insertions, 12 deletions

diff --git a/drivers/acpi/resources/rscreate.c b/drivers/acpi/resources/rscreate.c
index faddaee1bc07..7804a8c40e7a 100644
--- a/drivers/acpi/resources/rscreate.c
+++ b/drivers/acpi/resources/rscreate.c
@@ -181,9 +181,9 @@ acpi_rs_create_pci_routing_table(union acpi_operand_object *package_object,
         }
 
         /*
-         * Loop through the ACPI_INTERNAL_OBJECTS - Each object
-         * should be a package that in turn contains an
-         * acpi_integer Address, a u8 Pin, a Name and a u8 source_index.
+         * Loop through the ACPI_INTERNAL_OBJECTS - Each object should be a
+         * package that in turn contains an acpi_integer Address, a u8 Pin,
+         * a Name, and a u8 source_index.
          */
         top_object_list = package_object->package.elements;
         number_of_elements = package_object->package.count;
@@ -240,9 +240,7 @@ acpi_rs_create_pci_routing_table(union acpi_operand_object *package_object,
                 /* 1) First subobject: Dereference the PRT.Address */
 
                 obj_desc = sub_object_list[0];
-                if (ACPI_GET_OBJECT_TYPE(obj_desc) == ACPI_TYPE_INTEGER) {
-                        user_prt->address = obj_desc->integer.value;
-                } else {
+                if (ACPI_GET_OBJECT_TYPE(obj_desc) != ACPI_TYPE_INTEGER) {
                         ACPI_ERROR((AE_INFO,
                                     "(PRT[%X].Address) Need Integer, found %s",
                                     index,
@@ -250,12 +248,12 @@ acpi_rs_create_pci_routing_table(union acpi_operand_object *package_object,
                         return_ACPI_STATUS(AE_BAD_DATA);
                 }
 
+                user_prt->address = obj_desc->integer.value;
+
                 /* 2) Second subobject: Dereference the PRT.Pin */
 
                 obj_desc = sub_object_list[1];
-                if (ACPI_GET_OBJECT_TYPE(obj_desc) == ACPI_TYPE_INTEGER) {
-                        user_prt->pin = (u32) obj_desc->integer.value;
-                } else {
+                if (ACPI_GET_OBJECT_TYPE(obj_desc) != ACPI_TYPE_INTEGER) {
                         ACPI_ERROR((AE_INFO,
                                     "(PRT[%X].Pin) Need Integer, found %s",
                                     index,
@@ -284,6 +282,25 @@ acpi_rs_create_pci_routing_table(union acpi_operand_object *package_object,
                         }
                 }
 
+                user_prt->pin = (u32) obj_desc->integer.value;
+
+                /*
+                 * If the BIOS has erroneously reversed the _PRT source_name (index 2)
+                 * and the source_index (index 3), fix it. _PRT is important enough to
+                 * workaround this BIOS error. This also provides compatibility with
+                 * other ACPI implementations.
+                 */
+                obj_desc = sub_object_list[3];
+                if (!obj_desc
+                    || (ACPI_GET_OBJECT_TYPE(obj_desc) != ACPI_TYPE_INTEGER)) {
+                        sub_object_list[3] = sub_object_list[2];
+                        sub_object_list[2] = obj_desc;
+
+                        ACPI_WARNING((AE_INFO,
+                                      "(PRT[%X].Source) SourceName and SourceIndex are reversed, fixed",
+                                      index));
+                }
+
                 /*
                  * 3) Third subobject: Dereference the PRT.source_name
                  * The name may be unresolved (slack mode), so allow a null object
@@ -364,9 +381,7 @@ acpi_rs_create_pci_routing_table(union acpi_operand_object *package_object,
                 /* 4) Fourth subobject: Dereference the PRT.source_index */
 
                 obj_desc = sub_object_list[source_index_index];
-                if (ACPI_GET_OBJECT_TYPE(obj_desc) == ACPI_TYPE_INTEGER) {
-                        user_prt->source_index = (u32) obj_desc->integer.value;
-                } else {
+                if (ACPI_GET_OBJECT_TYPE(obj_desc) != ACPI_TYPE_INTEGER) {
                         ACPI_ERROR((AE_INFO,
                                     "(PRT[%X].SourceIndex) Need Integer, found %s",
                                     index,
@@ -374,6 +389,8 @@ acpi_rs_create_pci_routing_table(union acpi_operand_object *package_object,
                         return_ACPI_STATUS(AE_BAD_DATA);
                 }
 
+                user_prt->source_index = (u32) obj_desc->integer.value;
+
                 /* Point to the next union acpi_operand_object in the top level package */
 
                 top_object_list++;