ACPI / scan: Consolidate extraction of power resources lists

The lists of ACPI power resources are currently extracted in two
different ways, one for wakeup power resources and one for power
resources that device power states depend on.  There is no reason
why it should be done differently in those two cases, so introduce
a common routine for extracting power resources lists from data
returned by AML, acpi_extract_power_resources(), and make the
namespace scanning code use it for both wakeup and device power
states power resources.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

1 files changed, 21 insertions, 30 deletions

diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index 8da315418d94..d80df969f64a 100644
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -900,7 +900,6 @@ acpi_bus_extract_wakeup_device_power_package(acpi_handle handle,
 	union acpi_object *package = NULL;
 	union acpi_object *element = NULL;
 	acpi_status status;
-	int i = 0;
 
 	if (!wakeup)
 		return AE_BAD_PARAMETER;
@@ -953,18 +952,9 @@ acpi_bus_extract_wakeup_device_power_package(acpi_handle handle,
 	}
 	wakeup->sleep_state = element->integer.value;
 
-	for (i = 2; i < package->package.count; i++) {
-		acpi_handle rhandle;
-
-		element = &(package->package.elements[i]);
-		if (element->type != ACPI_TYPE_LOCAL_REFERENCE) {
-			status = AE_BAD_DATA;
-			goto out;
-		}
-		rhandle = element->reference.handle;
-		acpi_add_power_resource(rhandle);
-		acpi_power_resources_list_add(rhandle, &wakeup->resources);
-	}
+	status = acpi_extract_power_resources(package, 2, &wakeup->resources);
+	if (ACPI_FAILURE(status))
+		goto out;
 
 	acpi_setup_gpe_for_wake(handle, wakeup->gpe_device, wakeup->gpe_number);
 
@@ -1021,7 +1011,6 @@ static void acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
 	status = acpi_bus_extract_wakeup_device_power_package(device->handle,
 							      &device->wakeup);
 	if (ACPI_FAILURE(status)) {
-		acpi_power_resources_list_free(&device->wakeup.resources);
 		ACPI_EXCEPTION((AE_INFO, status, "Extracting _PRW package"));
 		return;
 	}
@@ -1044,30 +1033,32 @@ static void acpi_bus_get_wakeup_device_flags(struct acpi_device *device)
 static void acpi_bus_init_power_state(struct acpi_device *device, int state)
 {
 	struct acpi_device_power_state *ps = &device->power.states[state];
-	char object_name[5] = { '_', 'P', 'R', '0' + state, '\0' };
-	struct acpi_handle_list resources;
+	char pathname[5] = { '_', 'P', 'R', '0' + state, '\0' };
+	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 	acpi_handle handle;
 	acpi_status status;
 
 	INIT_LIST_HEAD(&ps->resources);
 
-	/* Evaluate "_PRx" to se if power resources are referenced */
-	acpi_evaluate_reference(device->handle, object_name, NULL, &resources);
-	if (resources.count) {
-		int j;
-
-		device->power.flags.power_resources = 1;
-		for (j = 0; j < resources.count; j++) {
-			acpi_handle rhandle = resources.handles[j];
-
-			acpi_add_power_resource(rhandle);
-			acpi_power_resources_list_add(rhandle, &ps->resources);
+	/* Evaluate "_PRx" to get referenced power resources */
+	status = acpi_evaluate_object(device->handle, pathname, NULL, &buffer);
+	if (ACPI_SUCCESS(status)) {
+		union acpi_object *package = buffer.pointer;
+
+		if (buffer.length && package
+		    && package->type == ACPI_TYPE_PACKAGE
+		    && package->package.count) {
+			status = acpi_extract_power_resources(package, 0,
+							      &ps->resources);
+			if (ACPI_SUCCESS(status))
+				device->power.flags.power_resources = 1;
 		}
+		ACPI_FREE(buffer.pointer);
 	}
 
 	/* Evaluate "_PSx" to see if we can do explicit sets */
-	object_name[2] = 'S';
-	status = acpi_get_handle(device->handle, object_name, &handle);
+	pathname[2] = 'S';
+	status = acpi_get_handle(device->handle, pathname, &handle);
 	if (ACPI_SUCCESS(status))
 		ps->flags.explicit_set = 1;
 
@@ -1075,7 +1066,7 @@ static void acpi_bus_init_power_state(struct acpi_device *device, int state)
 	 * State is valid if there are means to put the device into it.
 	 * D3hot is only valid if _PR3 present.
 	 */
-	if (resources.count
+	if (!list_empty(&ps->resources)
 	    || (ps->flags.explicit_set && state < ACPI_STATE_D3_HOT)) {
 		ps->flags.valid = 1;
 		ps->flags.os_accessible = 1;