ACPICA: Add write support for DataTable operation regions

The original implementation only supported reading from a DataTable
region. However, some machines have been seen that actually write
to the ACPI table contained in such a region. This change adds
support for writing to a DataTable region.

Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

1 files changed, 10 insertions, 3 deletions

diff --git a/drivers/acpi/acpica/exregion.c b/drivers/acpi/acpica/exregion.c
index a8703cc20ad1..531000fc77d2 100644
--- a/drivers/acpi/acpica/exregion.c
+++ b/drivers/acpi/acpica/exregion.c
@@ -491,8 +491,10 @@ acpi_ex_data_table_space_handler(u32 function,
 {
         ACPI_FUNCTION_TRACE(ex_data_table_space_handler);
 
-        /* Perform the memory read or write */
-
+        /*
+         * Perform the memory read or write. The bit_width was already
+         * validated.
+         */
         switch (function) {
         case ACPI_READ:
 
@@ -502,9 +504,14 @@ acpi_ex_data_table_space_handler(u32 function,
                 break;
 
         case ACPI_WRITE:
+
+                ACPI_MEMCPY(ACPI_PHYSADDR_TO_PTR(address),
+                            ACPI_CAST_PTR(char, value), ACPI_DIV_8(bit_width));
+                break;
+
         default:
 
-                return_ACPI_STATUS(AE_SUPPORT);
+                return_ACPI_STATUS(AE_BAD_PARAMETER);
         }
 
         return_ACPI_STATUS(AE_OK);