diff --git a/drivers/mtd/tests/mtd_speedtest.c b/drivers/mtd/tests/mtd_speedtest.c
index 596cbea8df4c..a6ce9c1fa6c5 100644
--- a/drivers/mtd/tests/mtd_speedtest.c
+++ b/drivers/mtd/tests/mtd_speedtest.c
@@ -49,13 +49,6 @@ static int pgcnt;
 static int goodebcnt;
 static struct timeval start, finish;
 
-static void set_random_data(unsigned char *buf, size_t len)
-{
-	size_t i;
-
-	for (i = 0; i < len; ++i)
-		buf[i] = random32();
-}
 
 static int erase_eraseblock(int ebnum)
 {
@@ -396,7 +389,7 @@ static int __init mtd_speedtest_init(void)
 		goto out;
 	}
 
-	set_random_data(iobuf, mtd->erasesize);
+	prandom_bytes(iobuf, mtd->erasesize);
 
 	err = scan_for_bad_eraseblocks();
 	if (err)