ACPI: EC: Allow multibyte access to EC

http://bugzilla.kernel.org/show_bug.cgi?id=14667

Signed-off-by: Alexey Starikovskiy <astarikovskiy@suse.de>
Signed-off-by: Len Brown <len.brown@intel.com>

1 files changed, 12 insertions, 0 deletions

diff --git a/drivers/acpi/acpica/exprep.c b/drivers/acpi/acpica/exprep.c
index edf62bf5b266..a610ebe18edd 100644
--- a/drivers/acpi/acpica/exprep.c
+++ b/drivers/acpi/acpica/exprep.c
@@ -468,6 +468,18 @@ acpi_status acpi_ex_prep_field_value(struct acpi_create_field_info *info)
 
                 acpi_ut_add_reference(obj_desc->field.region_obj);
 
+                /* allow full data read from EC address space */
+                if (obj_desc->field.region_obj->region.space_id ==
+                        ACPI_ADR_SPACE_EC) {
+                        if (obj_desc->common_field.bit_length > 8)
+                                obj_desc->common_field.access_bit_width =
+                                ACPI_ROUND_UP(obj_desc->common_field.
+                                                        bit_length, 8);
+                                obj_desc->common_field.access_byte_width =
+                                ACPI_DIV_8(obj_desc->common_field.
+                                                        access_bit_width);
+                }
+
                 ACPI_DEBUG_PRINT((ACPI_DB_BFIELD,
                                   "RegionField: BitOff %X, Off %X, Gran %X, Region %p\n",
                                   obj_desc->field.start_field_bit_offset,