Merge branch 'master' of git://git.denx.de/u-boot-nand-flash

1 files changed, 13 insertions, 1 deletions

diff --git a/drivers/mtd/mtdcore.c b/drivers/mtd/mtdcore.c
index 49c0814..deda5f2 100644
--- a/drivers/mtd/mtdcore.c
+++ b/drivers/mtd/mtdcore.c
@@ -217,11 +217,23 @@ int mtd_erase(struct mtd_info *mtd, struct erase_info *instr)
 int mtd_read(struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen,
 	     u_char *buf)
 {
+	int ret_code;
 	if (from < 0 || from > mtd->size || len > mtd->size - from)
 		return -EINVAL;
 	if (!len)
 		return 0;
-	return mtd->_read(mtd, from, len, retlen, buf);
+
+	/*
+	 * In the absence of an error, drivers return a non-negative integer
+	 * representing the maximum number of bitflips that were corrected on
+	 * any one ecc region (if applicable; zero otherwise).
+	 */
+	ret_code = mtd->_read(mtd, from, len, retlen, buf);
+	if (unlikely(ret_code < 0))
+		return ret_code;
+	if (mtd->ecc_strength == 0)
+		return 0;	/* device lacks ecc */
+	return ret_code >= mtd->bitflip_threshold ? -EUCLEAN : 0;
 }
 
 int mtd_write(struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen,