diff --git a/include/linux/ethtool.h b/include/linux/ethtool.h
index 3fad741df53e..c998f9c139ed 100644
--- a/include/linux/ethtool.h
+++ b/include/linux/ethtool.h
@@ -781,10 +781,10 @@ int ethtool_get_phc_vclocks(struct net_device *dev, int **vclock_index);
 
 /**
  * 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, ...);