ACPI: resume: re-enable SCI-enable workaround

The BIOS bug workaround mistakenly got disabled
when we followed the ACPI specification more closely
by ignoring OS updates to that bit.

(The BIOS is supposed to update SCI_EN, not the OS)

http://bugzilla.kernel.org/show_bug.cgi?id=13289

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

1 files changed, 6 insertions, 1 deletions

diff --git a/drivers/acpi/acpica/aclocal.h b/drivers/acpi/acpica/aclocal.h
index 772ee5c4ccca..2ec394a328e9 100644
--- a/drivers/acpi/acpica/aclocal.h
+++ b/drivers/acpi/acpica/aclocal.h
@@ -787,7 +787,12 @@ struct acpi_bit_register_info {
 
 /* For control registers, both ignored and reserved bits must be preserved */
 
-#define ACPI_PM1_CONTROL_IGNORED_BITS           0x0201  /* Bits 9, 0(SCI_EN) */
+/*
+ * The ACPI spec says to ignore PM1_CTL.SCI_EN (bit 0)
+ * but we need to be able to write ACPI_BITREG_SCI_ENABLE directly
+ * as a BIOS workaround on some machines.
+ */
+#define ACPI_PM1_CONTROL_IGNORED_BITS           0x0200  /* Bits 9 */
 #define ACPI_PM1_CONTROL_RESERVED_BITS          0xC1F8  /* Bits 14-15, 3-8 */
 #define ACPI_PM1_CONTROL_PRESERVED_BITS \
                (ACPI_PM1_CONTROL_IGNORED_BITS | ACPI_PM1_CONTROL_RESERVED_BITS)