ACPI: Use GPE reference counting to support shared GPEs

ACPI GPEs may map to multiple devices.  The current GPE interface
only provides a mechanism for enabling and disabling GPEs, making
it difficult to change the state of GPEs at runtime without extensive
cooperation between devices.

Add an API to allow devices to indicate whether or not they want
their device's GPE to be enabled for both runtime and wakeup events.

Remove the old GPE type handling entirely, which gets rid of various
quirks, like the implicit disabling with GPE type setting. This
requires a small amount of rework in order to ensure that non-wake
GPEs are enabled by default to preserve existing behaviour.

Based on patches from Matthew Garrett <mjg@redhat.com>.

Signed-off-by: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

1 files changed, 8 insertions, 6 deletions

diff --git a/drivers/acpi/ec.c b/drivers/acpi/ec.c
index d6471bb..0fa65a8 100644
--- a/drivers/acpi/ec.c
+++ b/drivers/acpi/ec.c
@@ -307,7 +307,7 @@ static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t)
 	pr_debug(PREFIX "transaction start\n");
 	/* disable GPE during transaction if storm is detected */
 	if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
-		acpi_disable_gpe(NULL, ec->gpe);
+		acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_DISABLE);
 	}
 
 	status = acpi_ec_transaction_unlocked(ec, t);
@@ -317,7 +317,7 @@ static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t)
 	if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
 		msleep(1);
 		/* it is safe to enable GPE outside of transaction */
-		acpi_enable_gpe(NULL, ec->gpe);
+		acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_ENABLE);
 	} else if (t->irq_count > ACPI_EC_STORM_THRESHOLD) {
 		pr_info(PREFIX "GPE storm detected, "
 			"transactions will use polling mode\n");
@@ -788,8 +788,8 @@ static int ec_install_handlers(struct acpi_ec *ec)
 				  &acpi_ec_gpe_handler, ec);
 	if (ACPI_FAILURE(status))
 		return -ENODEV;
-	acpi_set_gpe_type(NULL, ec->gpe, ACPI_GPE_TYPE_RUNTIME);
-	acpi_enable_gpe(NULL, ec->gpe);
+
+	acpi_enable_gpe(NULL, ec->gpe, ACPI_GPE_TYPE_RUNTIME);
 	status = acpi_install_address_space_handler(ec->handle,
 						    ACPI_ADR_SPACE_EC,
 						    &acpi_ec_space_handler,
@@ -806,6 +806,7 @@ static int ec_install_handlers(struct acpi_ec *ec)
 		} else {
 			acpi_remove_gpe_handler(NULL, ec->gpe,
 				&acpi_ec_gpe_handler);
+			acpi_disable_gpe(NULL, ec->gpe, ACPI_GPE_TYPE_RUNTIME);
 			return -ENODEV;
 		}
 	}
@@ -816,6 +817,7 @@ static int ec_install_handlers(struct acpi_ec *ec)
 
 static void ec_remove_handlers(struct acpi_ec *ec)
 {
+	acpi_disable_gpe(NULL, ec->gpe, ACPI_GPE_TYPE_RUNTIME);
 	if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle,
 				ACPI_ADR_SPACE_EC, &acpi_ec_space_handler)))
 		pr_err(PREFIX "failed to remove space handler\n");
@@ -1058,7 +1060,7 @@ static int acpi_ec_suspend(struct acpi_device *device, pm_message_t state)
 {
 	struct acpi_ec *ec = acpi_driver_data(device);
 	/* Stop using GPE */
-	acpi_disable_gpe(NULL, ec->gpe);
+	acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_DISABLE);
 	return 0;
 }
 
@@ -1066,7 +1068,7 @@ static int acpi_ec_resume(struct acpi_device *device)
 {
 	struct acpi_ec *ec = acpi_driver_data(device);
 	/* Enable use of GPE back */
-	acpi_enable_gpe(NULL, ec->gpe);
+	acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_ENABLE);
 	return 0;
 }