ACPI / ACPICA: Fix low-level GPE manipulation code

ACPICA uses acpi_ev_enable_gpe() for enabling GPEs at the low level,
which is incorrect, because this function only enables the GPE if the
corresponding bit in its enable register's enable_for_run mask is set.
This causes acpi_set_gpe() to work incorrectly if used for enabling
GPEs that were not previously enabled with acpi_enable_gpe().  As a
result, among other things, wakeup-only GPEs are never enabled by
acpi_enable_wakeup_device(), so the devices that use them are unable
to wake up the system.

To fix this issue remove acpi_ev_enable_gpe() and its counterpart
acpi_ev_disable_gpe() and replace acpi_hw_low_disable_gpe() with
acpi_hw_low_set_gpe() that will be used instead to manipulate GPE
enable bits at the low level.  Make the users of acpi_ev_enable_gpe()
and acpi_ev_disable_gpe() call acpi_hw_low_set_gpe() instead and
make sure that GPE enable masks are only updated by acpi_enable_gpe()
and acpi_disable_gpe() when GPE reference counters change from 0
to 1 and from 1 to 0, respectively.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Len Brown <len.brown@intel.com>

1 files changed, 21 insertions, 5 deletions

diff --git a/drivers/acpi/acpica/hwgpe.c b/drivers/acpi/acpica/hwgpe.c
index d989b8e786cc..40388e23e103 100644
--- a/drivers/acpi/acpica/hwgpe.c
+++ b/drivers/acpi/acpica/hwgpe.c
@@ -78,23 +78,27 @@ u32 acpi_hw_gpe_register_bit(struct acpi_gpe_event_info *gpe_event_info,
 
 /******************************************************************************
  *
- * FUNCTION:	acpi_hw_low_disable_gpe
+ * FUNCTION:	acpi_hw_low_set_gpe
  *
  * PARAMETERS:	gpe_event_info	    - Info block for the GPE to be disabled
+ *		action		    - Enable or disable
  *
  * RETURN:	Status
  *
- * DESCRIPTION: Disable a single GPE in the enable register.
+ * DESCRIPTION: Enable or disable a single GPE in its enable register.
  *
  ******************************************************************************/
 
-acpi_status acpi_hw_low_disable_gpe(struct acpi_gpe_event_info *gpe_event_info)
+acpi_status
+acpi_hw_low_set_gpe(struct acpi_gpe_event_info *gpe_event_info, u8 action)
 {
 	struct acpi_gpe_register_info *gpe_register_info;
 	acpi_status status;
 	u32 enable_mask;
 	u32 register_bit;
 
+	ACPI_FUNCTION_ENTRY();
+
 	/* Get the info block for the entire GPE register */
 
 	gpe_register_info = gpe_event_info->register_info;
@@ -109,11 +113,23 @@ acpi_status acpi_hw_low_disable_gpe(struct acpi_gpe_event_info *gpe_event_info)
 		return (status);
 	}
 
-	/* Clear just the bit that corresponds to this GPE */
+	/* Set ot clear just the bit that corresponds to this GPE */
 
 	register_bit = acpi_hw_gpe_register_bit(gpe_event_info,
 						gpe_register_info);
-	ACPI_CLEAR_BIT(enable_mask, register_bit);
+	switch (action) {
+	case ACPI_GPE_ENABLE:
+		ACPI_SET_BIT(enable_mask, register_bit);
+		break;
+
+	case ACPI_GPE_DISABLE:
+		ACPI_CLEAR_BIT(enable_mask, register_bit);
+		break;
+
+	default:
+		ACPI_ERROR((AE_INFO, "Invalid action\n"));
+		return (AE_BAD_PARAMETER);
+	}
 
 	/* Write the updated enable mask */