ACPICA: Fail AcpiEnable if ACPI tables not loaded.

AcpiEnable will now fail if all of the required ACPI tables are not
loaded (FADT, FACS, DSDT). BZ 477

Signed-off-by: Alexey Starikovskiy <alexey.y.starikovskiy@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

1 files changed, 23 insertions, 0 deletions

diff --git a/drivers/acpi/tables/tbutils.c b/drivers/acpi/tables/tbutils.c
index 0cb743962faf..0874ab299784 100644
--- a/drivers/acpi/tables/tbutils.c
+++ b/drivers/acpi/tables/tbutils.c
@@ -54,6 +54,29 @@ acpi_tb_get_root_table_entry(u8 * table_entry,
 
 /*******************************************************************************
  *
+ * FUNCTION:    acpi_tb_tables_loaded
+ *
+ * PARAMETERS:  None
+ *
+ * RETURN:      TRUE if required ACPI tables are loaded
+ *
+ * DESCRIPTION: Determine if the minimum required ACPI tables are present
+ *              (FADT, FACS, DSDT)
+ *
+ ******************************************************************************/
+
+u8 acpi_tb_tables_loaded(void)
+{
+
+        if (acpi_gbl_root_table_list.count >= 3) {
+                return (TRUE);
+        }
+
+        return (FALSE);
+}
+
+/*******************************************************************************
+ *
  * FUNCTION:    acpi_tb_print_table_header
  *
  * PARAMETERS:  Address             - Table physical address