1 files changed, 61 insertions, 0 deletions

diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c
index a7f5d432c95d..78c780d1ab89 100644
--- a/drivers/iio/industrialio-core.c
+++ b/drivers/iio/industrialio-core.c
@@ -185,6 +185,18 @@ int iio_device_id(struct iio_dev *indio_dev)
 EXPORT_SYMBOL_GPL(iio_device_id);
 
 /**
+ * iio_buffer_enabled() - helper function to test if the buffer is enabled
+ * @indio_dev:		IIO device structure for device
+ */
+bool iio_buffer_enabled(struct iio_dev *indio_dev)
+{
+	return indio_dev->currentmode
+		& (INDIO_BUFFER_TRIGGERED | INDIO_BUFFER_HARDWARE |
+		   INDIO_BUFFER_SOFTWARE);
+}
+EXPORT_SYMBOL_GPL(iio_buffer_enabled);
+
+/**
  * iio_sysfs_match_string_with_gaps - matches given string in an array with gaps
  * @array: array of strings
  * @n: number of strings in the array
@@ -2072,6 +2084,55 @@ 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);
+
+/**
+ * iio_device_get_current_mode() - helper function providing read-only access to
+ *				   the @currentmode variable
+ * @indio_dev:			   IIO device structure for device
+ */
+int iio_device_get_current_mode(struct iio_dev *indio_dev)
+{
+	return indio_dev->currentmode;
+}
+EXPORT_SYMBOL_GPL(iio_device_get_current_mode);
+
 subsys_initcall(iio_init);
 module_exit(iio_exit);