1 files changed, 4 insertions, 0 deletions

diff --git a/include/drm/drm_dp_helper.h b/include/drm/drm_dp_helper.h
index b4f58914bf7d..cfcacec5b89d 100644
--- a/include/drm/drm_dp_helper.h
+++ b/include/drm/drm_dp_helper.h
@@ -456,6 +456,10 @@ struct drm_dp_aux_msg {
  * transactions. The drm_dp_aux_register_i2c_bus() function registers an
  * I2C adapter that can be passed to drm_probe_ddc(). Upon removal, drivers
  * should call drm_dp_aux_unregister_i2c_bus() to remove the I2C adapter.
+ *
+ * Note that the aux helper code assumes that the .transfer() function
+ * only modifies the reply field of the drm_dp_aux_msg structure.  The
+ * retry logic and i2c helpers assume this is the case.
  */
 struct drm_dp_aux {
         const char *name;