diff --git a/src/widgets/buttonmatrix/lv_buttonmatrix.c b/src/widgets/buttonmatrix/lv_buttonmatrix.c
index 27befa32f2..06eeff5999 100644
--- a/src/widgets/buttonmatrix/lv_buttonmatrix.c
+++ b/src/widgets/buttonmatrix/lv_buttonmatrix.c
@@ -1036,8 +1036,8 @@ static void update_map(lv_obj_t * obj)
     const char * const * map_row = btnm->map_p;
 
     /*Count the units and the buttons in a line*/
-    uint32_t row;
-    for(row = 0; row < btnm->row_cnt; row++) {
+    int32_t row_cnt = (int32_t)btnm->row_cnt;
+    for(int32_t row = 0; row < row_cnt; row++) {
         uint32_t unit_cnt = 0;           /*Number of units in a row*/
         uint32_t btn_cnt = 0;            /*Number of buttons in a row*/
         /*Count the buttons and units in this row*/
@@ -1052,8 +1052,8 @@ static void update_map(lv_obj_t * obj)
             continue;
         }
 
-        int32_t row_y1 = stop + (max_h_no_gap * row) / btnm->row_cnt + row * prow;
-        int32_t row_y2 = stop + (max_h_no_gap * (row + 1)) / btnm->row_cnt + row * prow - 1;
+        int32_t row_y1 = stop + (max_h_no_gap * row) / row_cnt + row * prow;
+        int32_t row_y2 = stop + (max_h_no_gap * (row + 1)) / row_cnt + row * prow - 1;
 
         /*Set the button size and positions*/
         int32_t max_w_no_gap = max_w - (pcol * (btn_cnt - 1));