media: v4l: Set sub-device's owner field to the caller's module

Set a sub-device's owner field to the caller's module, provided as an
argument to the function. v4l2_device_register_subdev() becomes a macro
passing THIS_MODULE to the __v4l2_device_register_subdev() function.

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

5 files changed, 15 insertions, 10 deletions

diff --git a/drivers/media/v4l2-core/v4l2-async.c b/drivers/media/v4l2-core/v4l2-async.c
index 4bb073587817..b28f6811a5f4 100644
--- a/drivers/media/v4l2-core/v4l2-async.c
+++ b/drivers/media/v4l2-core/v4l2-async.c
@@ -341,7 +341,7 @@ static int v4l2_async_match_notify(struct v4l2_async_notifier *notifier,
 	int ret;
 
 	if (list_empty(&sd->asc_list)) {
-		ret = v4l2_device_register_subdev(v4l2_dev, sd);
+		ret = __v4l2_device_register_subdev(v4l2_dev, sd, sd->owner);
 		if (ret < 0)
 			return ret;
 		registered = true;
diff --git a/drivers/media/v4l2-core/v4l2-device.c b/drivers/media/v4l2-core/v4l2-device.c
index d2e58ae91f9b..5e537454f5cd 100644
--- a/drivers/media/v4l2-core/v4l2-device.c
+++ b/drivers/media/v4l2-core/v4l2-device.c
@@ -108,8 +108,8 @@ void v4l2_device_unregister(struct v4l2_device *v4l2_dev)
 }
 EXPORT_SYMBOL_GPL(v4l2_device_unregister);
 
-int v4l2_device_register_subdev(struct v4l2_device *v4l2_dev,
-				struct v4l2_subdev *sd)
+int __v4l2_device_register_subdev(struct v4l2_device *v4l2_dev,
+				  struct v4l2_subdev *sd, struct module *module)
 {
 	int err;
 
@@ -125,9 +125,9 @@ int v4l2_device_register_subdev(struct v4l2_device *v4l2_dev,
 	 * try_module_get() such sub-device owners.
 	 */
 	sd->owner_v4l2_dev = v4l2_dev->dev && v4l2_dev->dev->driver &&
-		sd->owner == v4l2_dev->dev->driver->owner;
+		module == v4l2_dev->dev->driver->owner;
 
-	if (!sd->owner_v4l2_dev && !try_module_get(sd->owner))
+	if (!sd->owner_v4l2_dev && !try_module_get(module))
 		return -ENODEV;
 
 	sd->v4l2_dev = v4l2_dev;
@@ -152,6 +152,8 @@ int v4l2_device_register_subdev(struct v4l2_device *v4l2_dev,
 			goto error_unregister;
 	}
 
+	sd->owner = module;
+
 	spin_lock(&v4l2_dev->lock);
 	list_add_tail(&sd->list, &v4l2_dev->subdevs);
 	spin_unlock(&v4l2_dev->lock);
@@ -168,7 +170,7 @@ error_module:
 	sd->v4l2_dev = NULL;
 	return err;
 }
-EXPORT_SYMBOL_GPL(v4l2_device_register_subdev);
+EXPORT_SYMBOL_GPL(__v4l2_device_register_subdev);
 
 static void v4l2_subdev_release(struct v4l2_subdev *sd)
 {
diff --git a/drivers/media/v4l2-core/v4l2-i2c.c b/drivers/media/v4l2-core/v4l2-i2c.c
index b4acca75644b..586c46544255 100644
--- a/drivers/media/v4l2-core/v4l2-i2c.c
+++ b/drivers/media/v4l2-core/v4l2-i2c.c
@@ -100,7 +100,7 @@ struct v4l2_subdev
 	 * Register with the v4l2_device which increases the module's
 	 * use count as well.
 	 */
-	if (v4l2_device_register_subdev(v4l2_dev, sd))
+	if (__v4l2_device_register_subdev(v4l2_dev, sd, sd->owner))
 		sd = NULL;
 	/* Decrease the module use count to match the first try_module_get. */
 	module_put(client->dev.driver->owner);
diff --git a/drivers/media/v4l2-core/v4l2-spi.c b/drivers/media/v4l2-core/v4l2-spi.c
index a7092c3930d6..1baf8e63f19e 100644
--- a/drivers/media/v4l2-core/v4l2-spi.c
+++ b/drivers/media/v4l2-core/v4l2-spi.c
@@ -59,7 +59,7 @@ struct v4l2_subdev *v4l2_spi_new_subdev(struct v4l2_device *v4l2_dev,
 	 * Register with the v4l2_device which increases the module's
 	 * use count as well.
 	 */
-	if (v4l2_device_register_subdev(v4l2_dev, sd))
+	if (__v4l2_device_register_subdev(v4l2_dev, sd, sd->owner))
 		sd = NULL;
 
 	/* Decrease the module use count to match the first try_module_get. */
diff --git a/include/media/v4l2-device.h b/include/media/v4l2-device.h
index f6f111fae33c..dd897a362f36 100644
--- a/include/media/v4l2-device.h
+++ b/include/media/v4l2-device.h
@@ -156,8 +156,11 @@ void v4l2_device_unregister(struct v4l2_device *v4l2_dev);
  * An error is returned if the module is no longer loaded on any attempts
  * to register it.
  */
-int __must_check v4l2_device_register_subdev(struct v4l2_device *v4l2_dev,
-					     struct v4l2_subdev *sd);
+#define v4l2_device_register_subdev(v4l2_dev, sd) \
+	__v4l2_device_register_subdev(v4l2_dev, sd, THIS_MODULE)
+int __must_check __v4l2_device_register_subdev(struct v4l2_device *v4l2_dev,
+					       struct v4l2_subdev *sd,
+					       struct module *module);
 
 /**
  * v4l2_device_unregister_subdev - Unregisters a subdev with a v4l2 device.