1 files changed, 42 insertions, 2 deletions

diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c
index 0b3d40ede39c6a..2d975e76302419 100644
--- a/drivers/iio/industrialio-core.c
+++ b/drivers/iio/industrialio-core.c
@@ -1673,6 +1673,7 @@ static const struct iio_buffer_setup_ops noop_ring_setup_ops;
 
 int __iio_device_register(struct iio_dev *indio_dev, struct module *this_mod)
 {
+	const char *label;
 	int ret;
 
 	indio_dev->driver_module = this_mod;
@@ -1680,8 +1681,9 @@ int __iio_device_register(struct iio_dev *indio_dev, struct module *this_mod)
 	if (!indio_dev->dev.of_node && indio_dev->dev.parent)
 		indio_dev->dev.of_node = indio_dev->dev.parent->of_node;
 
-	indio_dev->label = of_get_property(indio_dev->dev.of_node, "label",
-					   NULL);
+	label = of_get_property(indio_dev->dev.of_node, "label", NULL);
+	if (label)
+		indio_dev->label = label;
 
 	ret = iio_check_unique_scan_index(indio_dev);
 	if (ret < 0)
@@ -1832,6 +1834,44 @@ void iio_device_release_direct_mode(struct iio_dev *indio_dev)
 }
 EXPORT_SYMBOL_GPL(iio_device_release_direct_mode);
 
+/**
+ * iio_device_claim_buffer_mode - Keep device in buffer mode
+ * @indio_dev:	the iio_dev associated with the device
+ *
+ * If the device is in buffer mode it is guaranteed to stay
+ * that way until iio_device_release_buffer_mode() is called.
+ *
+ * Use with iio_device_release_buffer_mode().
+ *
+ * Returns: 0 on success, -EBUSY on failure.
+ */
+int iio_device_claim_buffer_mode(struct iio_dev *indio_dev)
+{
+	mutex_lock(&indio_dev->mlock);
+
+	if (iio_buffer_enabled(indio_dev))
+		return 0;
+
+	mutex_unlock(&indio_dev->mlock);
+	return -EBUSY;
+}
+EXPORT_SYMBOL_GPL(iio_device_claim_buffer_mode);
+
+/**
+ * iio_device_release_buffer_mode - releases claim on buffer mode
+ * @indio_dev:	the iio_dev associated with the device
+ *
+ * Release the claim. Device is no longer guaranteed to stay
+ * in buffer mode.
+ *
+ * Use with iio_device_claim_buffer_mode().
+ */
+void iio_device_release_buffer_mode(struct iio_dev *indio_dev)
+{
+	mutex_unlock(&indio_dev->mlock);
+}
+EXPORT_SYMBOL_GPL(iio_device_release_buffer_mode);
+
 subsys_initcall(iio_init);
 module_exit(iio_exit);