diff --git a/drivers/mtd/core.c b/drivers/mtd/core.c
index d954f72..d3e7763 100644
--- a/drivers/mtd/core.c
+++ b/drivers/mtd/core.c
@@ -403,7 +403,7 @@
 	if (IS_ENABLED(CONFIG_PARAMETER)) {
 		dev_add_param_int_ro(&mtd->class_dev, "size", mtd->size, "%llu");
 		dev_add_param_int_ro(&mtd->class_dev, "erasesize", mtd->erasesize, "%u");
-		dev_add_param_int_ro(&mtd->class_dev, "writesize", mtd->oobsize, "%u");
+		dev_add_param_int_ro(&mtd->class_dev, "writesize", mtd->writesize, "%u");
 		dev_add_param_int_ro(&mtd->class_dev, "oobsize", mtd->oobsize, "%u");
 	}