diff --git a/libavutil/lls.c b/libavutil/lls.c
index 13eea96fde..749163e68b 100644
--- a/libavutil/lls.c
+++ b/libavutil/lls.c
@@ -48,7 +48,7 @@ void avpriv_update_lls(LLSModel *m, double *var, double decay)
     }
 }
 
-void avpriv_solve_lls(LLSModel *m, double threshold, int min_order)
+void avpriv_solve_lls(LLSModel *m, double threshold, unsigned short min_order)
 {
     int i, j, k;
     double (*factor)[MAX_VARS + 1] = (void *) &m->covariance[1][0];
diff --git a/libavutil/lls.h b/libavutil/lls.h
index 0f02c8d6a5..d8d53d0a3d 100644
--- a/libavutil/lls.h
+++ b/libavutil/lls.h
@@ -39,7 +39,7 @@ typedef struct LLSModel {
 
 void avpriv_init_lls(LLSModel *m, int indep_count);
 void avpriv_update_lls(LLSModel *m, double *param, double decay);
-void avpriv_solve_lls(LLSModel *m, double threshold, int min_order);
+void avpriv_solve_lls(LLSModel *m, double threshold, unsigned short min_order);
 double avpriv_evaluate_lls(LLSModel *m, double *param, int order);
 
 #ifndef FF_API_LLS_PRIVATE