diff --git a/include/linux/ethtool.h b/include/linux/ethtool.h
index 226a36ed5aa1..689028257fcc 100644
--- a/include/linux/ethtool.h
+++ b/include/linux/ethtool.h
@@ -1045,10 +1045,10 @@ static inline int ethtool_mm_frag_size_min_to_add(u32 val_min, u32 *val_add,
 
 /**
  * ethtool_sprintf - Write formatted string to ethtool string data
- * @data: Pointer to start of string to update
+ * @data: Pointer to a pointer to the start of string to update
  * @fmt: Format of string to write
  *
- * Write formatted string to data. Update data to point at start of
+ * Write formatted string to *data. Update *data to point at start of
  * next string.
  */
 extern __printf(2, 3) void ethtool_sprintf(u8 **data, const char *fmt, ...);