1 files changed, 224 insertions, 89 deletions

diff --git a/drivers/media/v4l2-core/v4l2-async.c b/drivers/media/v4l2-core/v4l2-async.c
index 2b08d03b251d..a6d91370838d 100644
--- a/drivers/media/v4l2-core/v4l2-async.c
+++ b/drivers/media/v4l2-core/v4l2-async.c
@@ -57,6 +57,7 @@ static bool match_i2c(struct v4l2_subdev *sd, struct v4l2_async_subdev *asd)
 {
 #if IS_ENABLED(CONFIG_I2C)
 	struct i2c_client *client = i2c_verify_client(sd->dev);
+
 	return client &&
 		asd->match.i2c.adapter_id == client->adapter->nr &&
 		asd->match.i2c.address == client->addr;
@@ -89,10 +90,11 @@ static LIST_HEAD(subdev_list);
 static LIST_HEAD(notifier_list);
 static DEFINE_MUTEX(list_lock);
 
-static struct v4l2_async_subdev *v4l2_async_find_match(
-	struct v4l2_async_notifier *notifier, struct v4l2_subdev *sd)
+static struct v4l2_async_subdev *
+v4l2_async_find_match(struct v4l2_async_notifier *notifier,
+		      struct v4l2_subdev *sd)
 {
-	bool (*match)(struct v4l2_subdev *, struct v4l2_async_subdev *);
+	bool (*match)(struct v4l2_subdev *sd, struct v4l2_async_subdev *asd);
 	struct v4l2_async_subdev *asd;
 
 	list_for_each_entry(asd, &notifier->waiting, list) {
@@ -124,9 +126,34 @@ static struct v4l2_async_subdev *v4l2_async_find_match(
 	return NULL;
 }
 
+/* Compare two async sub-device descriptors for equivalence */
+static bool asd_equal(struct v4l2_async_subdev *asd_x,
+		      struct v4l2_async_subdev *asd_y)
+{
+	if (asd_x->match_type != asd_y->match_type)
+		return false;
+
+	switch (asd_x->match_type) {
+	case V4L2_ASYNC_MATCH_DEVNAME:
+		return strcmp(asd_x->match.device_name,
+			      asd_y->match.device_name) == 0;
+	case V4L2_ASYNC_MATCH_I2C:
+		return asd_x->match.i2c.adapter_id ==
+			asd_y->match.i2c.adapter_id &&
+			asd_x->match.i2c.address ==
+			asd_y->match.i2c.address;
+	case V4L2_ASYNC_MATCH_FWNODE:
+		return asd_x->match.fwnode == asd_y->match.fwnode;
+	default:
+		break;
+	}
+
+	return false;
+}
+
 /* Find the sub-device notifier registered by a sub-device driver. */
-static struct v4l2_async_notifier *v4l2_async_find_subdev_notifier(
-	struct v4l2_subdev *sd)
+static struct v4l2_async_notifier *
+v4l2_async_find_subdev_notifier(struct v4l2_subdev *sd)
 {
 	struct v4l2_async_notifier *n;
 
@@ -138,8 +165,8 @@ static struct v4l2_async_notifier *v4l2_async_find_subdev_notifier(
 }
 
 /* Get v4l2_device related to the notifier if one can be found. */
-static struct v4l2_device *v4l2_async_notifier_find_v4l2_dev(
-	struct v4l2_async_notifier *notifier)
+static struct v4l2_device *
+v4l2_async_notifier_find_v4l2_dev(struct v4l2_async_notifier *notifier)
 {
 	while (notifier->parent)
 		notifier = notifier->parent;
@@ -150,8 +177,8 @@ static struct v4l2_device *v4l2_async_notifier_find_v4l2_dev(
 /*
  * Return true if all child sub-device notifiers are complete, false otherwise.
  */
-static bool v4l2_async_notifier_can_complete(
-	struct v4l2_async_notifier *notifier)
+static bool
+v4l2_async_notifier_can_complete(struct v4l2_async_notifier *notifier)
 {
 	struct v4l2_subdev *sd;
 
@@ -174,8 +201,8 @@ static bool v4l2_async_notifier_can_complete(
  * Complete the master notifier if possible. This is done when all async
  * sub-devices have been bound; v4l2_device is also available then.
  */
-static int v4l2_async_notifier_try_complete(
-	struct v4l2_async_notifier *notifier)
+static int
+v4l2_async_notifier_try_complete(struct v4l2_async_notifier *notifier)
 {
 	/* Quick check whether there are still more sub-devices here. */
 	if (!list_empty(&notifier->waiting))
@@ -196,8 +223,8 @@ static int v4l2_async_notifier_try_complete(
 	return v4l2_async_notifier_call_complete(notifier);
 }
 
-static int v4l2_async_notifier_try_all_subdevs(
-	struct v4l2_async_notifier *notifier);
+static int
+v4l2_async_notifier_try_all_subdevs(struct v4l2_async_notifier *notifier);
 
 static int v4l2_async_match_notify(struct v4l2_async_notifier *notifier,
 				   struct v4l2_device *v4l2_dev,
@@ -243,8 +270,8 @@ static int v4l2_async_match_notify(struct v4l2_async_notifier *notifier,
 }
 
 /* Test all async sub-devices in a notifier for a match. */
-static int v4l2_async_notifier_try_all_subdevs(
-	struct v4l2_async_notifier *notifier)
+static int
+v4l2_async_notifier_try_all_subdevs(struct v4l2_async_notifier *notifier)
 {
 	struct v4l2_device *v4l2_dev =
 		v4l2_async_notifier_find_v4l2_dev(notifier);
@@ -281,14 +308,17 @@ again:
 static void v4l2_async_cleanup(struct v4l2_subdev *sd)
 {
 	v4l2_device_unregister_subdev(sd);
-	/* Subdevice driver will reprobe and put the subdev back onto the list */
+	/*
+	 * Subdevice driver will reprobe and put the subdev back
+	 * onto the list
+	 */
 	list_del_init(&sd->async_list);
 	sd->asd = NULL;
 }
 
 /* Unbind all sub-devices in the notifier tree. */
-static void v4l2_async_notifier_unbind_all_subdevs(
-	struct v4l2_async_notifier *notifier)
+static void
+v4l2_async_notifier_unbind_all_subdevs(struct v4l2_async_notifier *notifier)
 {
 	struct v4l2_subdev *sd, *tmp;
 
@@ -308,29 +338,23 @@ static void v4l2_async_notifier_unbind_all_subdevs(
 	notifier->parent = NULL;
 }
 
-/* See if an fwnode can be found in a notifier's lists. */
-static bool __v4l2_async_notifier_fwnode_has_async_subdev(
-	struct v4l2_async_notifier *notifier, struct fwnode_handle *fwnode)
+/* See if an async sub-device can be found in a notifier's lists. */
+static bool
+__v4l2_async_notifier_has_async_subdev(struct v4l2_async_notifier *notifier,
+				       struct v4l2_async_subdev *asd)
 {
-	struct v4l2_async_subdev *asd;
+	struct v4l2_async_subdev *asd_y;
 	struct v4l2_subdev *sd;
 
-	list_for_each_entry(asd, &notifier->waiting, list) {
-		if (asd->match_type != V4L2_ASYNC_MATCH_FWNODE)
-			continue;
-
-		if (asd->match.fwnode == fwnode)
+	list_for_each_entry(asd_y, &notifier->waiting, list)
+		if (asd_equal(asd, asd_y))
 			return true;
-	}
 
 	list_for_each_entry(sd, &notifier->done, async_list) {
 		if (WARN_ON(!sd->asd))
 			continue;
 
-		if (sd->asd->match_type != V4L2_ASYNC_MATCH_FWNODE)
-			continue;
-
-		if (sd->asd->match.fwnode == fwnode)
+		if (asd_equal(asd, sd->asd))
 			return true;
 	}
 
@@ -338,76 +362,91 @@ static bool __v4l2_async_notifier_fwnode_has_async_subdev(
 }
 
 /*
- * Find out whether an async sub-device was set up for an fwnode already or
+ * Find out whether an async sub-device was set up already or
  * whether it exists in a given notifier before @this_index.
+ * If @this_index < 0, search the notifier's entire @asd_list.
  */
-static bool v4l2_async_notifier_fwnode_has_async_subdev(
-	struct v4l2_async_notifier *notifier, struct fwnode_handle *fwnode,
-	unsigned int this_index)
+static bool
+v4l2_async_notifier_has_async_subdev(struct v4l2_async_notifier *notifier,
+				     struct v4l2_async_subdev *asd,
+				     int this_index)
 {
-	unsigned int j;
+	struct v4l2_async_subdev *asd_y;
+	int j = 0;
 
 	lockdep_assert_held(&list_lock);
 
-	/* Check that an fwnode is not being added more than once. */
-	for (j = 0; j < this_index; j++) {
-		struct v4l2_async_subdev *asd = notifier->subdevs[this_index];
-		struct v4l2_async_subdev *other_asd = notifier->subdevs[j];
-
-		if (other_asd->match_type == V4L2_ASYNC_MATCH_FWNODE &&
-		    asd->match.fwnode ==
-		    other_asd->match.fwnode)
+	/* Check that an asd is not being added more than once. */
+	list_for_each_entry(asd_y, &notifier->asd_list, asd_list) {
+		if (this_index >= 0 && j++ >= this_index)
+			break;
+		if (asd_equal(asd, asd_y))
 			return true;
 	}
 
-	/* Check than an fwnode did not exist in other notifiers. */
+	/* Check that an asd does not exist in other notifiers. */
 	list_for_each_entry(notifier, &notifier_list, list)
-		if (__v4l2_async_notifier_fwnode_has_async_subdev(
-			    notifier, fwnode))
+		if (__v4l2_async_notifier_has_async_subdev(notifier, asd))
 			return true;
 
 	return false;
 }
 
-static int __v4l2_async_notifier_register(struct v4l2_async_notifier *notifier)
+static int v4l2_async_notifier_asd_valid(struct v4l2_async_notifier *notifier,
+					 struct v4l2_async_subdev *asd,
+					 int this_index)
 {
 	struct device *dev =
 		notifier->v4l2_dev ? notifier->v4l2_dev->dev : NULL;
-	struct v4l2_async_subdev *asd;
-	int ret;
-	int i;
 
-	if (notifier->num_subdevs > V4L2_MAX_SUBDEVS)
+	if (!asd)
+		return -EINVAL;
+
+	switch (asd->match_type) {
+	case V4L2_ASYNC_MATCH_CUSTOM:
+	case V4L2_ASYNC_MATCH_DEVNAME:
+	case V4L2_ASYNC_MATCH_I2C:
+	case V4L2_ASYNC_MATCH_FWNODE:
+		if (v4l2_async_notifier_has_async_subdev(notifier, asd,
+							 this_index)) {
+			dev_dbg(dev, "subdev descriptor already listed in this or other notifiers\n");
+			return -EEXIST;
+		}
+		break;
+	default:
+		dev_err(dev, "Invalid match type %u on %p\n",
+			asd->match_type, asd);
 		return -EINVAL;
+	}
+
+	return 0;
+}
+
+void v4l2_async_notifier_init(struct v4l2_async_notifier *notifier)
+{
+	mutex_lock(&list_lock);
+
+	INIT_LIST_HEAD(&notifier->asd_list);
+
+	mutex_unlock(&list_lock);
+}
+EXPORT_SYMBOL(v4l2_async_notifier_init);
+
+static int __v4l2_async_notifier_register(struct v4l2_async_notifier *notifier)
+{
+	struct v4l2_async_subdev *asd;
+	int ret, i = 0;
 
 	INIT_LIST_HEAD(&notifier->waiting);
 	INIT_LIST_HEAD(&notifier->done);
 
 	mutex_lock(&list_lock);
 
-	for (i = 0; i < notifier->num_subdevs; i++) {
-		asd = notifier->subdevs[i];
-
-		switch (asd->match_type) {
-		case V4L2_ASYNC_MATCH_CUSTOM:
-		case V4L2_ASYNC_MATCH_DEVNAME:
-		case V4L2_ASYNC_MATCH_I2C:
-			break;
-		case V4L2_ASYNC_MATCH_FWNODE:
-			if (v4l2_async_notifier_fwnode_has_async_subdev(
-				    notifier, asd->match.fwnode, i)) {
-				dev_err(dev,
-					"fwnode has already been registered or in notifier's subdev list\n");
-				ret = -EEXIST;
-				goto err_unlock;
-			}
-			break;
-		default:
-			dev_err(dev, "Invalid match type %u on %p\n",
-				asd->match_type, asd);
-			ret = -EINVAL;
+	list_for_each_entry(asd, &notifier->asd_list, asd_list) {
+		ret = v4l2_async_notifier_asd_valid(notifier, asd, i++);
+		if (ret)
 			goto err_unlock;
-		}
+
 		list_add_tail(&asd->list, &notifier->waiting);
 	}
 
@@ -474,8 +513,8 @@ int v4l2_async_subdev_notifier_register(struct v4l2_subdev *sd,
 }
 EXPORT_SYMBOL(v4l2_async_subdev_notifier_register);
 
-static void __v4l2_async_notifier_unregister(
-	struct v4l2_async_notifier *notifier)
+static void
+__v4l2_async_notifier_unregister(struct v4l2_async_notifier *notifier)
 {
 	if (!notifier || (!notifier->v4l2_dev && !notifier->sd))
 		return;
@@ -498,36 +537,132 @@ void v4l2_async_notifier_unregister(struct v4l2_async_notifier *notifier)
 }
 EXPORT_SYMBOL(v4l2_async_notifier_unregister);
 
-void v4l2_async_notifier_cleanup(struct v4l2_async_notifier *notifier)
+static void __v4l2_async_notifier_cleanup(struct v4l2_async_notifier *notifier)
 {
-	unsigned int i;
+	struct v4l2_async_subdev *asd, *tmp;
 
-	if (!notifier || !notifier->max_subdevs)
+	if (!notifier)
 		return;
 
-	for (i = 0; i < notifier->num_subdevs; i++) {
-		struct v4l2_async_subdev *asd = notifier->subdevs[i];
-
+	list_for_each_entry_safe(asd, tmp, &notifier->asd_list, asd_list) {
 		switch (asd->match_type) {
 		case V4L2_ASYNC_MATCH_FWNODE:
 			fwnode_handle_put(asd->match.fwnode);
 			break;
 		default:
-			WARN_ON_ONCE(true);
 			break;
 		}
 
+		list_del(&asd->asd_list);
 		kfree(asd);
 	}
+}
 
-	notifier->max_subdevs = 0;
-	notifier->num_subdevs = 0;
+void v4l2_async_notifier_cleanup(struct v4l2_async_notifier *notifier)
+{
+	mutex_lock(&list_lock);
+
+	__v4l2_async_notifier_cleanup(notifier);
 
-	kvfree(notifier->subdevs);
-	notifier->subdevs = NULL;
+	mutex_unlock(&list_lock);
 }
 EXPORT_SYMBOL_GPL(v4l2_async_notifier_cleanup);
 
+int v4l2_async_notifier_add_subdev(struct v4l2_async_notifier *notifier,
+				   struct v4l2_async_subdev *asd)
+{
+	int ret;
+
+	mutex_lock(&list_lock);
+
+	ret = v4l2_async_notifier_asd_valid(notifier, asd, -1);
+	if (ret)
+		goto unlock;
+
+	list_add_tail(&asd->asd_list, &notifier->asd_list);
+
+unlock:
+	mutex_unlock(&list_lock);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(v4l2_async_notifier_add_subdev);
+
+struct v4l2_async_subdev *
+v4l2_async_notifier_add_fwnode_subdev(struct v4l2_async_notifier *notifier,
+				      struct fwnode_handle *fwnode,
+				      unsigned int asd_struct_size)
+{
+	struct v4l2_async_subdev *asd;
+	int ret;
+
+	asd = kzalloc(asd_struct_size, GFP_KERNEL);
+	if (!asd)
+		return ERR_PTR(-ENOMEM);
+
+	asd->match_type = V4L2_ASYNC_MATCH_FWNODE;
+	asd->match.fwnode = fwnode;
+
+	ret = v4l2_async_notifier_add_subdev(notifier, asd);
+	if (ret) {
+		kfree(asd);
+		return ERR_PTR(ret);
+	}
+
+	return asd;
+}
+EXPORT_SYMBOL_GPL(v4l2_async_notifier_add_fwnode_subdev);
+
+struct v4l2_async_subdev *
+v4l2_async_notifier_add_i2c_subdev(struct v4l2_async_notifier *notifier,
+				   int adapter_id, unsigned short address,
+				   unsigned int asd_struct_size)
+{
+	struct v4l2_async_subdev *asd;
+	int ret;
+
+	asd = kzalloc(asd_struct_size, GFP_KERNEL);
+	if (!asd)
+		return ERR_PTR(-ENOMEM);
+
+	asd->match_type = V4L2_ASYNC_MATCH_I2C;
+	asd->match.i2c.adapter_id = adapter_id;
+	asd->match.i2c.address = address;
+
+	ret = v4l2_async_notifier_add_subdev(notifier, asd);
+	if (ret) {
+		kfree(asd);
+		return ERR_PTR(ret);
+	}
+
+	return asd;
+}
+EXPORT_SYMBOL_GPL(v4l2_async_notifier_add_i2c_subdev);
+
+struct v4l2_async_subdev *
+v4l2_async_notifier_add_devname_subdev(struct v4l2_async_notifier *notifier,
+				       const char *device_name,
+				       unsigned int asd_struct_size)
+{
+	struct v4l2_async_subdev *asd;
+	int ret;
+
+	asd = kzalloc(asd_struct_size, GFP_KERNEL);
+	if (!asd)
+		return ERR_PTR(-ENOMEM);
+
+	asd->match_type = V4L2_ASYNC_MATCH_DEVNAME;
+	asd->match.device_name = device_name;
+
+	ret = v4l2_async_notifier_add_subdev(notifier, asd);
+	if (ret) {
+		kfree(asd);
+		return ERR_PTR(ret);
+	}
+
+	return asd;
+}
+EXPORT_SYMBOL_GPL(v4l2_async_notifier_add_devname_subdev);
+
 int v4l2_async_register_subdev(struct v4l2_subdev *sd)
 {
 	struct v4l2_async_notifier *subdev_notifier;
@@ -601,7 +736,7 @@ void v4l2_async_unregister_subdev(struct v4l2_subdev *sd)
 	mutex_lock(&list_lock);
 
 	__v4l2_async_notifier_unregister(sd->subdev_notifier);
-	v4l2_async_notifier_cleanup(sd->subdev_notifier);
+	__v4l2_async_notifier_cleanup(sd->subdev_notifier);
 	kfree(sd->subdev_notifier);
 	sd->subdev_notifier = NULL;