media: v4l: async: Introduce helpers for calling async ops callbacks

Add three helper functions to call async operations callbacks. Besides
simplifying callbacks, this allows async notifiers to have no ops set,
i.e. it can be left NULL.

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Acked-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Reviewed-by: Sebastian Reichel <sebastian.reichel@collabora.co.uk>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

drivers/media/v4l2-core/v4l2-async.c

@@ -25,6 +25,34 @@
 #include <media/v4l2-fwnode.h>
 #include <media/v4l2-subdev.h>
 
+static int v4l2_async_notifier_call_bound(struct v4l2_async_notifier *n,
+					  struct v4l2_subdev *subdev,
+					  struct v4l2_async_subdev *asd)
+{
+	if (!n->ops || !n->ops->bound)
+		return 0;
+
+	return n->ops->bound(n, subdev, asd);
+}
+
+static void v4l2_async_notifier_call_unbind(struct v4l2_async_notifier *n,
+					    struct v4l2_subdev *subdev,
+					    struct v4l2_async_subdev *asd)
+{
+	if (!n->ops || !n->ops->unbind)
+		return;
+
+	n->ops->unbind(n, subdev, asd);
+}
+
+static int v4l2_async_notifier_call_complete(struct v4l2_async_notifier *n)
+{
+	if (!n->ops || !n->ops->complete)
+		return 0;
+
+	return n->ops->complete(n);
+}
+
 static bool match_i2c(struct v4l2_subdev *sd, struct v4l2_async_subdev *asd)
 {
 #if IS_ENABLED(CONFIG_I2C)
@@ -102,16 +130,13 @@ static int v4l2_async_match_notify(struct v4l2_async_notifier *notifier,
 {
 	int ret;
 
-	if (notifier->ops->bound) {
-		ret = notifier->ops->bound(notifier, sd, asd);
-		if (ret < 0)
-			return ret;
-	}
+	ret = v4l2_async_notifier_call_bound(notifier, sd, asd);
+	if (ret < 0)
+		return ret;
 
 	ret = v4l2_device_register_subdev(notifier->v4l2_dev, sd);
 	if (ret < 0) {
-		if (notifier->ops->unbind)
-			notifier->ops->unbind(notifier, sd, asd);
+		v4l2_async_notifier_call_unbind(notifier, sd, asd);
 		return ret;
 	}
 
@@ -140,8 +165,7 @@ static void v4l2_async_notifier_unbind_all_subdevs(
 	struct v4l2_subdev *sd, *tmp;
 
 	list_for_each_entry_safe(sd, tmp, &notifier->done, async_list) {
-		if (notifier->ops->unbind)
-			notifier->ops->unbind(notifier, sd, sd->asd);
+		v4l2_async_notifier_call_unbind(notifier, sd, sd->asd);
 		v4l2_async_cleanup(sd);
 
 		list_move(&sd->async_list, &subdev_list);
@@ -198,8 +222,8 @@ int v4l2_async_notifier_register(struct v4l2_device *v4l2_dev,
 		}
 	}
 
-	if (list_empty(&notifier->waiting) && notifier->ops->complete) {
-		ret = notifier->ops->complete(notifier);
+	if (list_empty(&notifier->waiting)) {
+		ret = v4l2_async_notifier_call_complete(notifier);
 		if (ret)
 			goto err_complete;
 	}
@@ -296,10 +320,10 @@ int v4l2_async_register_subdev(struct v4l2_subdev *sd)
 		if (ret)
 			goto err_unlock;
 
-		if (!list_empty(&notifier->waiting) || !notifier->ops->complete)
+		if (!list_empty(&notifier->waiting))
 			goto out_unlock;
 
-		ret = notifier->ops->complete(notifier);
+		ret = v4l2_async_notifier_call_complete(notifier);
 		if (ret)
 			goto err_cleanup;
 
@@ -315,8 +339,7 @@ out_unlock:
 	return 0;
 
 err_cleanup:
-	if (notifier->ops->unbind)
-		notifier->ops->unbind(notifier, sd, sd->asd);
+	v4l2_async_notifier_call_unbind(notifier, sd, sd->asd);
 	v4l2_async_cleanup(sd);
 
 err_unlock:
@@ -335,8 +358,7 @@ void v4l2_async_unregister_subdev(struct v4l2_subdev *sd)
 
 		list_add(&sd->asd->list, &notifier->waiting);
 
-		if (notifier->ops->unbind)
-			notifier->ops->unbind(notifier, sd, sd->asd);
+		v4l2_async_notifier_call_unbind(notifier, sd, sd->asd);
 	}
 
 	v4l2_async_cleanup(sd);