diff options
author | Maxim Levitsky <maximlevitsky@gmail.com> | 2010-02-22 20:39:39 +0200 |
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committer | David Woodhouse <David.Woodhouse@intel.com> | 2010-02-26 18:04:51 +0000 |
commit | 9fc51a37a8da84618df7584cad67c078317f6720 (patch) | |
tree | 937893100ff63faad8f8f8fa82486dbbeee70fb6 /drivers/mtd/nand/sm_common.c | |
parent | e0b58d0a7005cd4b9c7fa4694a437a2d86719c13 (diff) | |
download | linux-9fc51a37a8da84618df7584cad67c078317f6720.tar.bz2 |
mtd: common module for smartmedia/xD support
This small module implements few helpers that are usefull
for nand drivers for SmartMedia/xD card readers.
Signed-off-by: Maxim Levitsky <maximlevitsky@gmail.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Diffstat (limited to 'drivers/mtd/nand/sm_common.c')
-rw-r--r-- | drivers/mtd/nand/sm_common.c | 107 |
1 files changed, 107 insertions, 0 deletions
diff --git a/drivers/mtd/nand/sm_common.c b/drivers/mtd/nand/sm_common.c new file mode 100644 index 000000000000..07b6f725723f --- /dev/null +++ b/drivers/mtd/nand/sm_common.c @@ -0,0 +1,107 @@ +/* + * Copyright © 2009 - Maxim Levitsky + * Common routines & support for xD format + * + * 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 + * published by the Free Software Foundation. + */ +#include <linux/kernel.h> +#include <linux/mtd/nand.h> +#include "sm_common.h" + +static struct nand_ecclayout nand_oob_sm = { + .eccbytes = 6, + .eccpos = {8, 9, 10, 13, 14, 15}, + .oobfree = { + {.offset = 0 , .length = 4}, /* reserved */ + {.offset = 6 , .length = 2}, /* LBA1 */ + {.offset = 11, .length = 2} /* LBA2 */ + } +}; + +/* NOTE: This layout is is not compatabable with SmartMedia, */ +/* because the 256 byte devices have page depenent oob layout */ +/* However it does preserve the bad block markers */ +/* If you use smftl, it will bypass this and work correctly */ +/* If you not, then you break SmartMedia compliance anyway */ + +static struct nand_ecclayout nand_oob_sm_small = { + .eccbytes = 3, + .eccpos = {0, 1, 2}, + .oobfree = { + {.offset = 3 , .length = 2}, /* reserved */ + {.offset = 6 , .length = 2}, /* LBA1 */ + } +}; + + +static int sm_block_markbad(struct mtd_info *mtd, loff_t ofs) +{ + struct mtd_oob_ops ops; + struct sm_oob oob; + int ret, error = 0; + + memset(&oob, -1, SM_OOB_SIZE); + oob.block_status = 0x0F; + + /* As long as this function is called on erase block boundaries + it will work correctly for 256 byte nand */ + ops.mode = MTD_OOB_PLACE; + ops.ooboffs = 0; + ops.ooblen = mtd->oobsize; + ops.oobbuf = (void *)&oob; + ops.datbuf = NULL; + + + ret = mtd->write_oob(mtd, ofs, &ops); + if (ret < 0 || ops.oobretlen != SM_OOB_SIZE) { + printk(KERN_NOTICE + "sm_common: can't mark sector at %i as bad\n", + (int)ofs); + error = -EIO; + } else + mtd->ecc_stats.badblocks++; + + return error; +} + + +int sm_register_device(struct mtd_info *mtd) +{ + struct nand_chip *chip = (struct nand_chip *)mtd->priv; + int ret; + + chip->options |= NAND_SKIP_BBTSCAN | NAND_SMARTMEDIA; + + /* Scan for card properties */ + ret = nand_scan_ident(mtd, 1); + + if (ret) + return ret; + + /* Bad block marker postion */ + chip->badblockpos = 0x05; + chip->badblockbits = 7; + chip->block_markbad = sm_block_markbad; + + /* ECC layout */ + if (mtd->writesize == SM_SECTOR_SIZE) + chip->ecc.layout = &nand_oob_sm; + else if (mtd->writesize == SM_SMALL_PAGE) + chip->ecc.layout = &nand_oob_sm_small; + else + return -ENODEV; + + ret = nand_scan_tail(mtd); + + if (ret) + return ret; + + return add_mtd_device(mtd); +} +EXPORT_SYMBOL_GPL(sm_register_device); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Maxim Levitsky <maximlevitsky@gmail.com>"); +MODULE_DESCRIPTION("Common SmartMedia/xD functions"); |