[MTD] NAND Signal that a bitflip was corrected by ECC

Return -EUCLEAN on read when a bitflip was detected and corrected, so the
clients can react and eventually copy the affected block to a spare one.
Make all in kernel users aware of the change.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

1 files changed, 12 insertions, 3 deletions

diff --git a/drivers/mtd/mtdconcat.c b/drivers/mtd/mtdconcat.c
index 38151b8e6631..3c8d5e6fa010 100644
--- a/drivers/mtd/mtdconcat.c
+++ b/drivers/mtd/mtdconcat.c
@@ -56,7 +56,7 @@ concat_read(struct mtd_info *mtd, loff_t from, size_t len,
             size_t * retlen, u_char * buf)
 {
         struct mtd_concat *concat = CONCAT(mtd);
-        int err = -EINVAL;
+        int ret = 0, err = -EINVAL;
         int i;
 
         *retlen = 0;
@@ -80,9 +80,18 @@ concat_read(struct mtd_info *mtd, loff_t from, size_t len,
 
                 err = subdev->read(subdev, from, size, &retsize, buf);
 
-                if (err)
+                if (err && (err != -EBADMSG) && (err != -EUCLEAN))
                         break;
 
+                /* Save information about bitflips! */
+                if (err) {
+                        if (err == -EBADMSG)
+                                ret = err;
+                        else if (!ret)
+                                ret = err;
+                        err = 0;
+                }
+
                 *retlen += retsize;
                 len -= size;
                 if (len == 0)
@@ -92,7 +101,7 @@ concat_read(struct mtd_info *mtd, loff_t from, size_t len,
                 buf += size;
                 from = 0;
         }
-        return err;
+        return err ? err : ret;
 }
 
 static int