[MTD] NAND: Fix bad block table scan for small page devices

Scan 1st and 2nd pages of SP devices for BB marker by default.
Fix more then one page scanning in create_bbt.c.

Signed-off-by: Artem B. Bityuckiy <dedekind@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

1 files changed, 30 insertions, 29 deletions

diff --git a/drivers/mtd/nand/nand_bbt.c b/drivers/mtd/nand/nand_bbt.c
index 5ff6eba8bec6..c85c69dec540 100644
--- a/drivers/mtd/nand/nand_bbt.c
+++ b/drivers/mtd/nand/nand_bbt.c
@@ -6,7 +6,7 @@
  *   
  *  Copyright (C) 2004 Thomas Gleixner (tglx@linutronix.de)
  *
- * $Id: nand_bbt.c,v 1.30 2005/02/11 10:14:12 dedekind Exp $
+ * $Id: nand_bbt.c,v 1.31 2005/02/16 17:09:36 dedekind Exp $
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 as
@@ -77,17 +77,17 @@
 */
 static int check_pattern (uint8_t *buf, int len, int paglen, struct nand_bbt_descr *td)
 {
-        int i, end;
+        int i, end = 0;
         uint8_t *p = buf;
 
-        end = paglen + td->offs;
         if (td->options & NAND_BBT_SCANEMPTY) {
+                end = paglen + td->offs;
                 for (i = 0; i < end; i++) {
                         if (p[i] != 0xff)
                                 return -1;
                 }
+                p += end;
         }       
-        p += end;
         
         /* Compare the pattern */
         for (i = 0; i < td->len; i++) {
@@ -95,9 +95,9 @@ static int check_pattern (uint8_t *buf, int len, int paglen, struct nand_bbt_des
                         return -1;
         }
 
-        p += td->len;
-        end += td->len;
         if (td->options & NAND_BBT_SCANEMPTY) {
+                p += td->len;
+                end += td->len;
                 for (i = end; i < len; i++) {
                         if (*p++ != 0xff)
                                 return -1;
@@ -255,7 +255,7 @@ static int read_abs_bbts (struct mtd_info *mtd, uint8_t *buf, struct nand_bbt_de
 static int create_bbt (struct mtd_info *mtd, uint8_t *buf, struct nand_bbt_descr *bd, int chip)
 {
         struct nand_chip *this = mtd->priv;
-        int i, j, numblocks, len, scanlen, pagelen;
+        int i, j, numblocks, len, scanlen;
         int startblock;
         loff_t from;
         size_t readlen, ooblen;
@@ -270,17 +270,16 @@ static int create_bbt (struct mtd_info *mtd, uint8_t *buf, struct nand_bbt_descr
                 else    
                         len = 1;
         }
-        
-        if (bd->options == 0) {
-                /* Memory-based BBT. We may read only needed bytes from the OOB area to
-                 * test if block is bad, no need to read the whole page content. */
-                scanlen = ooblen = pagelen = 0;
+
+        if (!(bd->options & NAND_BBT_SCANEMPTY)) {
+                /* We need only read few bytes from the OOB area */
+                scanlen = ooblen = 0;
                 readlen = bd->len;
         } else {
+                /* Full page content should be read */
                 scanlen = mtd->oobblock + mtd->oobsize;
                 readlen = len * mtd->oobblock;
                 ooblen = len * mtd->oobsize;
-                pagelen = mtd->oobblock;
         }
 
         if (chip == -1) {
@@ -293,7 +292,7 @@ static int create_bbt (struct mtd_info *mtd, uint8_t *buf, struct nand_bbt_descr
                 if (chip >= this->numchips) {
                         printk (KERN_WARNING "create_bbt(): chipnr (%d) > available chips (%d)\n",
                                 chip + 1, this->numchips);
-                        return -EINVAL; 
+                        return -EINVAL;
                 }
                 numblocks = this->chipsize >> (this->bbt_erase_shift - 1);
                 startblock = chip * numblocks;
@@ -304,16 +303,21 @@ static int create_bbt (struct mtd_info *mtd, uint8_t *buf, struct nand_bbt_descr
         for (i = startblock; i < numblocks;) {
                 int ret;
                 
-                if (bd->options == 0) {
-                        size_t retlen;
-                        if ((ret = mtd->read_oob(mtd, from + bd->offs, bd->len, &retlen, &buf[bd->offs])))
-                                return ret;
-                } else {
+                if (bd->options & NAND_BBT_SCANEMPTY)
                         if ((ret = nand_read_raw (mtd, buf, from, readlen, ooblen)))
                                 return ret;
-                }
+
                 for (j = 0; j < len; j++) {
-                        if (check_pattern (&buf[j * scanlen], scanlen, pagelen, bd)) {
+                        if (!(bd->options & NAND_BBT_SCANEMPTY)) {
+                                size_t retlen;
+                                
+                                /* No need to read pages fully, just read required OOB bytes */
+                                ret = mtd->read_oob(mtd, from + j * mtd->oobblock + bd->offs,
+                                                        readlen, &retlen, &buf[0]);
+                                if (ret)
+                                        return ret;
+                        }
+                        if (check_pattern (&buf[j * scanlen], scanlen, mtd->oobblock, bd)) {
                                 this->bbt[i >> 3] |= 0x03 << (i & 0x6);
                                 printk (KERN_WARNING "Bad eraseblock %d at 0x%08x\n", 
                                         i >> 1, (unsigned int) from);
@@ -323,6 +327,7 @@ static int create_bbt (struct mtd_info *mtd, uint8_t *buf, struct nand_bbt_descr
                 i += 2;
                 from += (1 << this->bbt_erase_shift);
         }
+
         return 0;
 }
 
@@ -608,12 +613,11 @@ write:
  * The function creates a memory based bbt by scanning the device 
  * for manufacturer / software marked good / bad blocks
 */
-static int nand_memory_bbt (struct mtd_info *mtd, struct nand_bbt_descr *bd)
+static inline int nand_memory_bbt (struct mtd_info *mtd, struct nand_bbt_descr *bd)
 {
         struct nand_chip *this = mtd->priv;
 
-        /* Ensure that we only scan for the pattern and nothing else */
-        bd->options = 0;
+        bd->options &= ~NAND_BBT_SCANEMPTY;
         return create_bbt (mtd, this->data_buf, bd, -1);
 }
 
@@ -928,14 +932,11 @@ out:
 }
 
 /* Define some generic bad / good block scan pattern which are used 
- * while scanning a device for factory marked good / bad blocks
- * 
- * The memory based patterns just 
- */
+ * while scanning a device for factory marked good / bad blocks. */
 static uint8_t scan_ff_pattern[] = { 0xff, 0xff };
 
 static struct nand_bbt_descr smallpage_memorybased = {
-        .options = 0,
+        .options = NAND_BBT_SCAN2NDPAGE,
         .offs = 5,
         .len = 1,
         .pattern = scan_ff_pattern