1 files changed, 27 insertions, 13 deletions

diff --git a/drivers/mtd/devices/docg3.c b/drivers/mtd/devices/docg3.c
index 50aa90aa7a7f..f70854d728fe 100644
--- a/drivers/mtd/devices/docg3.c
+++ b/drivers/mtd/devices/docg3.c
@@ -227,7 +227,7 @@ static void doc_read_data_area(struct docg3 *docg3, void *buf, int len,
         u8 data8, *dst8;
 
         doc_dbg("doc_read_data_area(buf=%p, len=%d)\n", buf, len);
-        cdr = len & 0x3;
+        cdr = len & 0x1;
         len4 = len - cdr;
 
         if (first)
@@ -732,12 +732,24 @@ err:
  * @len: the number of bytes to be read (must be a multiple of 4)
  * @buf: the buffer to be filled in (or NULL is forget bytes)
  * @first: 1 if first time read, DOC_READADDRESS should be set
+ * @last_odd: 1 if last read ended up on an odd byte
+ *
+ * Reads bytes from a prepared page. There is a trickery here : if the last read
+ * ended up on an odd offset in the 1024 bytes double page, ie. between the 2
+ * planes, the first byte must be read apart. If a word (16bit) read was used,
+ * the read would return the byte of plane 2 as low *and* high endian, which
+ * will mess the read.
  *
  */
 static int doc_read_page_getbytes(struct docg3 *docg3, int len, u_char *buf,
-                                  int first)
+                                  int first, int last_odd)
 {
-        doc_read_data_area(docg3, buf, len, first);
+        if (last_odd && len > 0) {
+                doc_read_data_area(docg3, buf, 1, first);
+                doc_read_data_area(docg3, buf ? buf + 1 : buf, len - 1, 0);
+        } else {
+                doc_read_data_area(docg3, buf, len, first);
+        }
         doc_delay(docg3, 2);
         return len;
 }
@@ -850,6 +862,7 @@ static int doc_read_oob(struct mtd_info *mtd, loff_t from,
         u8 *buf = ops->datbuf;
         size_t len, ooblen, nbdata, nboob;
         u8 hwecc[DOC_ECC_BCH_SIZE], eccconf1;
+        int max_bitflips = 0;
 
         if (buf)
                 len = ops->len;
@@ -876,7 +889,7 @@ static int doc_read_oob(struct mtd_info *mtd, loff_t from,
         ret = 0;
         skip = from % DOC_LAYOUT_PAGE_SIZE;
         mutex_lock(&docg3->cascade->lock);
-        while (!ret && (len > 0 || ooblen > 0)) {
+        while (ret >= 0 && (len > 0 || ooblen > 0)) {
                 calc_block_sector(from - skip, &block0, &block1, &page, &ofs,
                         docg3->reliable);
                 nbdata = min_t(size_t, len, DOC_LAYOUT_PAGE_SIZE - skip);
@@ -887,20 +900,20 @@ static int doc_read_oob(struct mtd_info *mtd, loff_t from,
                 ret = doc_read_page_ecc_init(docg3, DOC_ECC_BCH_TOTAL_BYTES);
                 if (ret < 0)
                         goto err_in_read;
-                ret = doc_read_page_getbytes(docg3, skip, NULL, 1);
+                ret = doc_read_page_getbytes(docg3, skip, NULL, 1, 0);
                 if (ret < skip)
                         goto err_in_read;
-                ret = doc_read_page_getbytes(docg3, nbdata, buf, 0);
+                ret = doc_read_page_getbytes(docg3, nbdata, buf, 0, skip % 2);
                 if (ret < nbdata)
                         goto err_in_read;
                 doc_read_page_getbytes(docg3,
                                        DOC_LAYOUT_PAGE_SIZE - nbdata - skip,
-                                       NULL, 0);
-                ret = doc_read_page_getbytes(docg3, nboob, oobbuf, 0);
+                                       NULL, 0, (skip + nbdata) % 2);
+                ret = doc_read_page_getbytes(docg3, nboob, oobbuf, 0, 0);
                 if (ret < nboob)
                         goto err_in_read;
                 doc_read_page_getbytes(docg3, DOC_LAYOUT_OOB_SIZE - nboob,
-                                       NULL, 0);
+                                       NULL, 0, nboob % 2);
 
                 doc_get_bch_hw_ecc(docg3, hwecc);
                 eccconf1 = doc_register_readb(docg3, DOC_ECCCONF1);
@@ -936,7 +949,8 @@ static int doc_read_oob(struct mtd_info *mtd, loff_t from,
                         }
                         if (ret > 0) {
                                 mtd->ecc_stats.corrected += ret;
-                                ret = -EUCLEAN;
+                                max_bitflips = max(max_bitflips, ret);
+                                ret = max_bitflips;
                         }
                 }
 
@@ -1004,7 +1018,7 @@ static int doc_reload_bbt(struct docg3 *docg3)
                                                      DOC_LAYOUT_PAGE_SIZE);
                 if (!ret)
                         doc_read_page_getbytes(docg3, DOC_LAYOUT_PAGE_SIZE,
-                                               buf, 1);
+                                               buf, 1, 0);
                 buf += DOC_LAYOUT_PAGE_SIZE;
         }
         doc_read_page_finish(docg3);
@@ -1064,10 +1078,10 @@ static int doc_get_erase_count(struct docg3 *docg3, loff_t from)
         ret = doc_reset_seq(docg3);
         if (!ret)
                 ret = doc_read_page_prepare(docg3, block0, block1, page,
-                                            ofs + DOC_LAYOUT_WEAR_OFFSET);
+                                            ofs + DOC_LAYOUT_WEAR_OFFSET, 0);
         if (!ret)
                 ret = doc_read_page_getbytes(docg3, DOC_LAYOUT_WEAR_SIZE,
-                                             buf, 1);
+                                             buf, 1, 0);
         doc_read_page_finish(docg3);
 
         if (ret || (buf[0] != DOC_ERASE_MARK) || (buf[2] != DOC_ERASE_MARK))