From d194011eed48da0b3f73228d40b781103555deb3 Mon Sep 17 00:00:00 2001
From: Brian Norris <computersforpeace@gmail.com>
Date: Fri, 22 Jun 2012 16:35:39 -0700
Subject: [PATCH] --- yaml --- r: 332678 b: refs/heads/master c:
 e47f68587b8255410e79166cbdecae290ca8a84e h: refs/heads/master v: v3

---
 [refs]                      |  2 +-
 trunk/drivers/mtd/mtdcore.c | 14 +++++++++++++-
 2 files changed, 14 insertions(+), 2 deletions(-)

diff --git a/[refs] b/[refs]
index 173fb8adb351..9b363ca2c04d 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 8bb8b85f6732ed579222a465d0749f66a3cace4d
+refs/heads/master: e47f68587b8255410e79166cbdecae290ca8a84e
diff --git a/trunk/drivers/mtd/mtdcore.c b/trunk/drivers/mtd/mtdcore.c
index fcfce24f87d1..ec794a72975d 100644
--- a/trunk/drivers/mtd/mtdcore.c
+++ b/trunk/drivers/mtd/mtdcore.c
@@ -860,10 +860,22 @@ EXPORT_SYMBOL_GPL(mtd_panic_write);
 
 int mtd_read_oob(struct mtd_info *mtd, loff_t from, struct mtd_oob_ops *ops)
 {
+	int ret_code;
 	ops->retlen = ops->oobretlen = 0;
 	if (!mtd->_read_oob)
 		return -EOPNOTSUPP;
-	return mtd->_read_oob(mtd, from, ops);
+	/*
+	 * In cases where ops->datbuf != NULL, mtd->_read_oob() has semantics
+	 * similar to mtd->_read(), returning a non-negative integer
+	 * representing max bitflips. In other cases, mtd->_read_oob() may
+	 * return -EUCLEAN. In all cases, perform similar logic to mtd_read().
+	 */
+	ret_code = mtd->_read_oob(mtd, from, ops);
+	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;
 }
 EXPORT_SYMBOL_GPL(mtd_read_oob);