PM / QoS: Add type to dev_pm_qos_add_ancestor_request() arguments

Rework dev_pm_qos_add_ancestor_request() so that device PM QoS type
is passed to it as the third argument and make it support the
DEV_PM_QOS_LATENCY_TOLERANCE device PM QoS type (in addition to
DEV_PM_QOS_RESUME_LATENCY).

That will allow the drivers of devices without latency tolerance
hardware support to use their ancestors having it as proxies for
their latency tolerance requirements.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
diff --git a/drivers/base/power/qos.c b/drivers/base/power/qos.c
index 84756f7..36b9eb4 100644
--- a/drivers/base/power/qos.c
+++ b/drivers/base/power/qos.c
@@ -565,20 +565,32 @@
  * dev_pm_qos_add_ancestor_request - Add PM QoS request for device's ancestor.
  * @dev: Device whose ancestor to add the request for.
  * @req: Pointer to the preallocated handle.
+ * @type: Type of the request.
  * @value: Constraint latency value.
  */
 int dev_pm_qos_add_ancestor_request(struct device *dev,
-				    struct dev_pm_qos_request *req, s32 value)
+				    struct dev_pm_qos_request *req,
+				    enum dev_pm_qos_req_type type, s32 value)
 {
 	struct device *ancestor = dev->parent;
 	int ret = -ENODEV;
 
-	while (ancestor && !ancestor->power.ignore_children)
-		ancestor = ancestor->parent;
+	switch (type) {
+	case DEV_PM_QOS_RESUME_LATENCY:
+		while (ancestor && !ancestor->power.ignore_children)
+			ancestor = ancestor->parent;
 
+		break;
+	case DEV_PM_QOS_LATENCY_TOLERANCE:
+		while (ancestor && !ancestor->power.set_latency_tolerance)
+			ancestor = ancestor->parent;
+
+		break;
+	default:
+		ancestor = NULL;
+	}
 	if (ancestor)
-		ret = dev_pm_qos_add_request(ancestor, req,
-					     DEV_PM_QOS_RESUME_LATENCY, value);
+		ret = dev_pm_qos_add_request(ancestor, req, type, value);
 
 	if (ret < 0)
 		req->dev = NULL;