diff --git a/drivers/crypto/hifn_795x.c b/drivers/crypto/hifn_795x.c
index 925991526745..edf36f6add52 100644
--- a/drivers/crypto/hifn_795x.c
+++ b/drivers/crypto/hifn_795x.c
@@ -913,11 +913,10 @@ static void hifn_init_pll(struct hifn_device *dev)
 	else
 		pllcfg |= HIFN_PLL_REF_CLK_HBI;
 
-	if (hifn_pll_ref[3] != '\0')
-		freq = simple_strtoul(hifn_pll_ref + 3, NULL, 10);
-	else {
+	if (hifn_pll_ref[3] == '\0' ||
+	    kstrtouint(hifn_pll_ref + 3, 10, &freq)) {
 		freq = 66;
-		dev_info(&dev->pdev->dev, "assuming %uMHz clock speed, override with hifn_pll_ref=%.3s<frequency>\n",
+		dev_info(&dev->pdev->dev, "assuming %u MHz clock speed, override with hifn_pll_ref=%.3s<frequency>\n",
 			 freq, hifn_pll_ref);
 	}