ACPI: delete _GTS/_BFS support

_GTS and _BFS were added to the suspend/resume flow
in the ACPI 2.0 specification.

Linux dutifully implemented _GTS and _BFS.
We discovered that it was rarely seen in systems
in the field.  Further, some of those systems had
AML so bogus that it could never work -- proof that
no other operating system supports _GTS and _BFS.
So we made _GTS and _BFS optional via modparam,
and disabled them by default.

But we've had to complicate some code to keep
this support in the kernel, as these methods are defined
to be evaluated very close to sleep entry and exit.
Indeed, no other AML is ever evaluated with interrupts off.

We have submitted a proposal for _GTS and _BFS
to be officially removed from the ACPI specification
on the next revision.  Here we remove it from Linux.

Signed-off-by: Len Brown <len.brown@intel.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>

1 files changed, 3 insertions, 16 deletions

diff --git a/drivers/acpi/acpica/hwesleep.c b/drivers/acpi/acpica/hwesleep.c
index 48518da..94996f9 100644
--- a/drivers/acpi/acpica/hwesleep.c
+++ b/drivers/acpi/acpica/hwesleep.c
@@ -90,7 +90,6 @@ void acpi_hw_execute_sleep_method(char *method_pathname, u32 integer_argument)
  * FUNCTION:    acpi_hw_extended_sleep
  *
  * PARAMETERS:  sleep_state         - Which sleep state to enter
- *              flags               - ACPI_EXECUTE_GTS to run optional method
  *
  * RETURN:      Status
  *
@@ -100,7 +99,7 @@ void acpi_hw_execute_sleep_method(char *method_pathname, u32 integer_argument)
  *
  ******************************************************************************/
 
-acpi_status acpi_hw_extended_sleep(u8 sleep_state, u8 flags)
+acpi_status acpi_hw_extended_sleep(u8 sleep_state)
 {
 	acpi_status status;
 	u8 sleep_type_value;
@@ -125,12 +124,6 @@ acpi_status acpi_hw_extended_sleep(u8 sleep_state, u8 flags)
 
 	acpi_gbl_system_awake_and_running = FALSE;
 
-	/* Optionally execute _GTS (Going To Sleep) */
-
-	if (flags & ACPI_EXECUTE_GTS) {
-		acpi_hw_execute_sleep_method(METHOD_PATHNAME__GTS, sleep_state);
-	}
-
 	/* Flush caches, as per ACPI specification */
 
 	ACPI_FLUSH_CPU_CACHE();
@@ -172,7 +165,6 @@ acpi_status acpi_hw_extended_sleep(u8 sleep_state, u8 flags)
  * FUNCTION:    acpi_hw_extended_wake_prep
  *
  * PARAMETERS:  sleep_state         - Which sleep state we just exited
- *              flags               - ACPI_EXECUTE_BFS to run optional method
  *
  * RETURN:      Status
  *
@@ -181,7 +173,7 @@ acpi_status acpi_hw_extended_sleep(u8 sleep_state, u8 flags)
  *
  ******************************************************************************/
 
-acpi_status acpi_hw_extended_wake_prep(u8 sleep_state, u8 flags)
+acpi_status acpi_hw_extended_wake_prep(u8 sleep_state)
 {
 	acpi_status status;
 	u8 sleep_type_value;
@@ -200,11 +192,6 @@ acpi_status acpi_hw_extended_wake_prep(u8 sleep_state, u8 flags)
 				 &acpi_gbl_FADT.sleep_control);
 	}
 
-	/* Optionally execute _BFS (Back From Sleep) */
-
-	if (flags & ACPI_EXECUTE_BFS) {
-		acpi_hw_execute_sleep_method(METHOD_PATHNAME__BFS, sleep_state);
-	}
 	return_ACPI_STATUS(AE_OK);
 }
 
@@ -222,7 +209,7 @@ acpi_status acpi_hw_extended_wake_prep(u8 sleep_state, u8 flags)
  *
  ******************************************************************************/
 
-acpi_status acpi_hw_extended_wake(u8 sleep_state, u8 flags)
+acpi_status acpi_hw_extended_wake(u8 sleep_state)
 {
 	ACPI_FUNCTION_TRACE(hw_extended_wake);