NAND bad blocks

[J.D. Bakker]

Hi all,

There's a slight discrepancy between what mtd and mkyaffs consider a bad block.

 From mtd/drivers/mtd/nand/nand.c:

   static int nand_block_bad(struct mtd_info *mtd, unsigned long page)
   {
         struct nand_chip *this = mtd->priv;

         this->cmdfunc (mtd, NAND_CMD_READOOB, NAND_BADBLOCK_POS, page);
         if (this->read_byte(mtd) != 0xff)
                 return 1;

         return 0;
   }

...which would indicate that even one bit set to zero would mark the 
block bad. However, mkyaffs.c has this code:

   /* Read the OOB data to determine if the block is valid.
    * If the block is damaged, then byte 5 of the OOB data will
    * have at least 2 zero bits.
    */

..snip..

   if(countBits[oobbuf[5]] < 7)
   {
	printf("Block at 0x08%lx is damaged and is not being 
formatted\n",addr);
   }

So, which is it ?

JDB
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