diff --git a/drivers/dfu/dfu_nand.c b/drivers/dfu/dfu_nand.c
index 6ddf80b..e53b35e 100644
--- a/drivers/dfu/dfu_nand.c
+++ b/drivers/dfu/dfu_nand.c
@@ -215,9 +215,9 @@
 
 		dfu->layout = DFU_RAW_ADDR;
 
-		dev = simple_strtoul(s, &s, 10);
+		dev = dectoul(s, &s);
 		s++;
-		part = simple_strtoul(s, &s, 10);
+		part = dectoul(s, &s);
 
 		sprintf(mtd_id, "%s%d,%d", "nand", dev, part - 1);
 		debug("using id '%s'\n", mtd_id);