iio: buffer-dmaengine: remove non managed alloc/free

This is to encourage the use of devm_iio_dmaengine_buffer_alloc().
Currently the managed version of the DMAEngine buffer alloc is the only
function used from this part of the framework.
Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Link: https://lore.kernel.org/r/20200923121810.944075-1-alexandru.ardelean@analog.comSigned-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

drivers/iio/buffer/industrialio-buffer-dmaengine.c

@@ -159,7 +159,7 @@ static const struct attribute *iio_dmaengine_buffer_attrs[] = {
  * Once done using the buffer iio_dmaengine_buffer_free() should be used to
  * release it.
  */
-struct iio_buffer *iio_dmaengine_buffer_alloc(struct device *dev,
+static struct iio_buffer *iio_dmaengine_buffer_alloc(struct device *dev,
 	const char *channel)
 {
 	struct dmaengine_buffer *dmaengine_buffer;
@@ -211,7 +211,6 @@ struct iio_buffer *iio_dmaengine_buffer_alloc(struct device *dev,
 	kfree(dmaengine_buffer);
 	return ERR_PTR(ret);
 }
-EXPORT_SYMBOL(iio_dmaengine_buffer_alloc);
 
 /**
  * iio_dmaengine_buffer_free() - Free dmaengine buffer
@@ -219,7 +218,7 @@ EXPORT_SYMBOL(iio_dmaengine_buffer_alloc);
  *
  * Frees a buffer previously allocated with iio_dmaengine_buffer_alloc().
  */
-void iio_dmaengine_buffer_free(struct iio_buffer *buffer)
+static void iio_dmaengine_buffer_free(struct iio_buffer *buffer)
 {
 	struct dmaengine_buffer *dmaengine_buffer =
 		iio_buffer_to_dmaengine_buffer(buffer);
@@ -229,7 +228,6 @@ void iio_dmaengine_buffer_free(struct iio_buffer *buffer)
 
 	iio_buffer_put(buffer);
 }
-EXPORT_SYMBOL_GPL(iio_dmaengine_buffer_free);
 
 static void __devm_iio_dmaengine_buffer_free(struct device *dev, void *res)
 {

include/linux/iio/buffer-dmaengine.h

@@ -10,10 +10,6 @@
 struct iio_buffer;
 struct device;
 
-struct iio_buffer *iio_dmaengine_buffer_alloc(struct device *dev,
-	const char *channel);
-void iio_dmaengine_buffer_free(struct iio_buffer *buffer);
-
 struct iio_buffer *devm_iio_dmaengine_buffer_alloc(struct device *dev,
 						   const char *channel);