iio: buffer: Move iio_buffer_alloc_sysfs and iio_buffer_free_sysfs

The next patch will introduce new dependencies in iio_buffer_alloc_sysfs()
to functions which are currently defined after iio_buffer_alloc_sysfs(). To
avoid forward declarations move both iio_buffer_alloc_sysfs() and
iio_buffer_free_sysfs() after those function.

This is split into two patches one moving the functions and one adding the
dependencies to make review of the actual changes easier.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

drivers/iio/industrialio-buffer.c

@@ -383,100 +383,6 @@ static int iio_buffer_add_channel_sysfs(struct iio_dev *indio_dev,
 	return ret;
 }
 
-static const char * const iio_scan_elements_group_name = "scan_elements";
-
-int iio_buffer_alloc_sysfs_and_mask(struct iio_dev *indio_dev)
-{
-	struct iio_dev_attr *p;
-	struct attribute **attr;
-	struct iio_buffer *buffer = indio_dev->buffer;
-	int ret, i, attrn, attrcount, attrcount_orig = 0;
-	const struct iio_chan_spec *channels;
-
-	if (!buffer)
-		return 0;
-
-	if (buffer->attrs)
-		indio_dev->groups[indio_dev->groupcounter++] = buffer->attrs;
-
-	if (buffer->scan_el_attrs != NULL) {
-		attr = buffer->scan_el_attrs->attrs;
-		while (*attr++ != NULL)
-			attrcount_orig++;
-	}
-	attrcount = attrcount_orig;
-	INIT_LIST_HEAD(&buffer->scan_el_dev_attr_list);
-	channels = indio_dev->channels;
-	if (channels) {
-		/* new magic */
-		for (i = 0; i < indio_dev->num_channels; i++) {
-			if (channels[i].scan_index < 0)
-				continue;
-
-			/* Establish necessary mask length */
-			if (channels[i].scan_index >
-			    (int)indio_dev->masklength - 1)
-				indio_dev->masklength
-					= channels[i].scan_index + 1;
-
-			ret = iio_buffer_add_channel_sysfs(indio_dev,
-							 &channels[i]);
-			if (ret < 0)
-				goto error_cleanup_dynamic;
-			attrcount += ret;
-			if (channels[i].type == IIO_TIMESTAMP)
-				indio_dev->scan_index_timestamp =
-					channels[i].scan_index;
-		}
-		if (indio_dev->masklength && buffer->scan_mask == NULL) {
-			buffer->scan_mask = kcalloc(BITS_TO_LONGS(indio_dev->masklength),
-						    sizeof(*buffer->scan_mask),
-						    GFP_KERNEL);
-			if (buffer->scan_mask == NULL) {
-				ret = -ENOMEM;
-				goto error_cleanup_dynamic;
-			}
-		}
-	}
-
-	buffer->scan_el_group.name = iio_scan_elements_group_name;
-
-	buffer->scan_el_group.attrs = kcalloc(attrcount + 1,
-					      sizeof(buffer->scan_el_group.attrs[0]),
-					      GFP_KERNEL);
-	if (buffer->scan_el_group.attrs == NULL) {
-		ret = -ENOMEM;
-		goto error_free_scan_mask;
-	}
-	if (buffer->scan_el_attrs)
-		memcpy(buffer->scan_el_group.attrs, buffer->scan_el_attrs,
-		       sizeof(buffer->scan_el_group.attrs[0])*attrcount_orig);
-	attrn = attrcount_orig;
-
-	list_for_each_entry(p, &buffer->scan_el_dev_attr_list, l)
-		buffer->scan_el_group.attrs[attrn++] = &p->dev_attr.attr;
-	indio_dev->groups[indio_dev->groupcounter++] = &buffer->scan_el_group;
-
-	return 0;
-
-error_free_scan_mask:
-	kfree(buffer->scan_mask);
-error_cleanup_dynamic:
-	iio_free_chan_devattr_list(&buffer->scan_el_dev_attr_list);
-
-	return ret;
-}
-
-void iio_buffer_free_sysfs_and_mask(struct iio_dev *indio_dev)
-{
-	if (!indio_dev->buffer)
-		return;
-
-	kfree(indio_dev->buffer->scan_mask);
-	kfree(indio_dev->buffer->scan_el_group.attrs);
-	iio_free_chan_devattr_list(&indio_dev->buffer->scan_el_dev_attr_list);
-}
-
 ssize_t iio_buffer_read_length(struct device *dev,
 			       struct device_attribute *attr,
 			       char *buf)
@@ -855,6 +761,97 @@ ssize_t iio_buffer_store_enable(struct device *dev,
 }
 EXPORT_SYMBOL(iio_buffer_store_enable);
 
+static const char * const iio_scan_elements_group_name = "scan_elements";
+
+int iio_buffer_alloc_sysfs_and_mask(struct iio_dev *indio_dev)
+{
+	struct iio_dev_attr *p;
+	struct attribute **attr;
+	struct iio_buffer *buffer = indio_dev->buffer;
+	int ret, i, attrn, attrcount, attrcount_orig = 0;
+	const struct iio_chan_spec *channels;
+
+	if (!buffer)
+		return 0;
+
+	if (buffer->scan_el_attrs != NULL) {
+		attr = buffer->scan_el_attrs->attrs;
+		while (*attr++ != NULL)
+			attrcount_orig++;
+	}
+	attrcount = attrcount_orig;
+	INIT_LIST_HEAD(&buffer->scan_el_dev_attr_list);
+	channels = indio_dev->channels;
+	if (channels) {
+		/* new magic */
+		for (i = 0; i < indio_dev->num_channels; i++) {
+			if (channels[i].scan_index < 0)
+				continue;
+
+			/* Establish necessary mask length */
+			if (channels[i].scan_index >
+			    (int)indio_dev->masklength - 1)
+				indio_dev->masklength
+					= channels[i].scan_index + 1;
+
+			ret = iio_buffer_add_channel_sysfs(indio_dev,
+							 &channels[i]);
+			if (ret < 0)
+				goto error_cleanup_dynamic;
+			attrcount += ret;
+			if (channels[i].type == IIO_TIMESTAMP)
+				indio_dev->scan_index_timestamp =
+					channels[i].scan_index;
+		}
+		if (indio_dev->masklength && buffer->scan_mask == NULL) {
+			buffer->scan_mask = kcalloc(BITS_TO_LONGS(indio_dev->masklength),
+						    sizeof(*buffer->scan_mask),
+						    GFP_KERNEL);
+			if (buffer->scan_mask == NULL) {
+				ret = -ENOMEM;
+				goto error_cleanup_dynamic;
+			}
+		}
+	}
+
+	buffer->scan_el_group.name = iio_scan_elements_group_name;
+
+	buffer->scan_el_group.attrs = kcalloc(attrcount + 1,
+					      sizeof(buffer->scan_el_group.attrs[0]),
+					      GFP_KERNEL);
+	if (buffer->scan_el_group.attrs == NULL) {
+		ret = -ENOMEM;
+		goto error_free_scan_mask;
+	}
+	if (buffer->scan_el_attrs)
+		memcpy(buffer->scan_el_group.attrs, buffer->scan_el_attrs,
+		       sizeof(buffer->scan_el_group.attrs[0])*attrcount_orig);
+	attrn = attrcount_orig;
+
+	list_for_each_entry(p, &buffer->scan_el_dev_attr_list, l)
+		buffer->scan_el_group.attrs[attrn++] = &p->dev_attr.attr;
+	indio_dev->groups[indio_dev->groupcounter++] = &buffer->scan_el_group;
+
+	return 0;
+
+error_free_scan_mask:
+	kfree(buffer->scan_mask);
+error_cleanup_dynamic:
+	iio_free_chan_devattr_list(&buffer->scan_el_dev_attr_list);
+
+	return ret;
+}
+
+void iio_buffer_free_sysfs_and_mask(struct iio_dev *indio_dev)
+{
+	if (!indio_dev->buffer)
+		return;
+
+	kfree(indio_dev->buffer->scan_mask);
+	kfree(indio_dev->buffer->scan_el_group.attrs);
+	iio_free_chan_devattr_list(&indio_dev->buffer->scan_el_dev_attr_list);
+}
+
 /**
  * iio_validate_scan_mask_onehot() - Validates that exactly one channel is selected
  * @indio_dev: the iio device