Messages in this thread Patch in this message | | | From | Maxim Levitsky <> | Subject | [PATCH 14/17] MTD: common module for smartmedia/xD support | Date | Tue, 9 Feb 2010 18:57:42 +0200 |
| |
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> --- drivers/mtd/nand/Kconfig | 9 +++ drivers/mtd/nand/Makefile | 1 + drivers/mtd/nand/sm_common.c | 114 ++++++++++++++++++++++++++++++++++++++++++ drivers/mtd/nand/sm_common.h | 61 ++++++++++++++++++++++ 4 files changed, 185 insertions(+), 0 deletions(-) create mode 100644 drivers/mtd/nand/sm_common.c create mode 100644 drivers/mtd/nand/sm_common.h
diff --git a/drivers/mtd/nand/Kconfig b/drivers/mtd/nand/Kconfig index 677cd53..13c1fb2 100644 --- a/drivers/mtd/nand/Kconfig +++ b/drivers/mtd/nand/Kconfig @@ -18,6 +18,10 @@ config MTD_NAND_VERIFY_WRITE device thinks the write was successful, a bit could have been flipped accidentally due to device wear or something else. +config MTD_NAND_SMARTMEDIA + boolean + default n + config MTD_NAND_ECC_SMC bool "NAND ECC Smart Media byte order" default n @@ -25,6 +29,11 @@ config MTD_NAND_ECC_SMC Software ECC according to the Smart Media Specification. The original Linux implementation had byte 0 and 1 swapped. +config MTD_SM_COMMON + select MTD_NAND_SMARTMEDIA + tristate + default n + config MTD_NAND_MUSEUM_IDS bool "Enable chip ids for obsolete ancient NAND devices" depends on MTD_NAND diff --git a/drivers/mtd/nand/Makefile b/drivers/mtd/nand/Makefile index 1407bd1..09891f6 100644 --- a/drivers/mtd/nand/Makefile +++ b/drivers/mtd/nand/Makefile @@ -4,6 +4,7 @@ obj-$(CONFIG_MTD_NAND) += nand.o nand_ecc.o obj-$(CONFIG_MTD_NAND_IDS) += nand_ids.o +obj-$(CONFIG_MTD_SM_COMMON) += sm_common.o obj-$(CONFIG_MTD_NAND_CAFE) += cafe_nand.o obj-$(CONFIG_MTD_NAND_SPIA) += spia.o diff --git a/drivers/mtd/nand/sm_common.c b/drivers/mtd/nand/sm_common.c new file mode 100644 index 0000000..64d8ee0 --- /dev/null +++ b/drivers/mtd/nand/sm_common.c @@ -0,0 +1,114 @@ +/* + * Copyright (C) 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 */ + } +}; + +/* Tests if block (more correctly page) is bad */ +static int sm_block_bad(struct mtd_info *mtd, loff_t ofs) +{ + struct mtd_oob_ops ops; + struct sm_oob oob; + int ret; + + ops.mode = MTD_OOB_PLACE; + ops.ooboffs = 0; + ops.ooblen = SM_OOB_SIZE; + ops.oobbuf = (void *)&oob; + ops.datbuf = NULL; + + ret = mtd->read_oob(mtd, ofs, &ops); + + /* We can just assume that read error means bad block... */ + if (ret < 0 || ops.oobretlen != SM_OOB_SIZE) + return 0; + + if (!sm_sector_valid(&oob) || !sm_block_valid(&oob)) + return 1; + + return 0; +} + +/* Marks block as bad */ +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.data_status = 0; + + ops.mode = MTD_OOB_PLACE; + ops.ooboffs = 0; + ops.ooblen = SM_OOB_SIZE; + 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; + + /* Set oob handling functions. */ + if (mtd->writesize == SM_SECTOR_SIZE) { + chip->block_bad = sm_block_bad; + chip->block_markbad = sm_block_markbad; + chip->ecc.layout = &nand_oob_sm; + + /* SmartMedia on small page nand, has page depedent oob layout, + thus let FTL do that hard job */ + } else if (mtd->writesize != SM_SMALL_PAGE) + return -ENODEV; + + ret = nand_scan_tail(mtd); + if (ret) + return ret; + + ret = add_mtd_device(mtd); + if (ret) + return ret; + return 0; +} +EXPORT_SYMBOL_GPL(sm_register_device); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Maxim Levitsky <maximlevitsky@gmail.com>"); +MODULE_DESCRIPTION("Common SmartMedia/xD functions"); diff --git a/drivers/mtd/nand/sm_common.h b/drivers/mtd/nand/sm_common.h new file mode 100644 index 0000000..2e6b517 --- /dev/null +++ b/drivers/mtd/nand/sm_common.h @@ -0,0 +1,61 @@ +/* + * Copyright (C) 2009 - Maxim Levitsky + * Common routines & support for SmartMedia/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/bitops.h> +#include <linux/mtd/mtd.h> + +/* Full oob structure as written on the flash */ +struct sm_oob { + u32 reserved; + u8 data_status; + u8 block_status; + u8 lba_copy1[2]; + u8 ecc2[3]; + u8 lba_copy2[2]; + u8 ecc1[3]; +} __attribute__((packed)); + + +/* one sector is always 512 bytes, but it can consist of two nand pages */ +#define SM_SECTOR_SIZE 512 + +/* oob area is also 16 bytes, but might be from two pages */ +#define SM_OOB_SIZE 16 + +/* This is maximum zone size, and all devices that have more that one zone + have this size */ +#define SM_MAX_ZONE_SIZE 1024 + +/* support for small page nand */ +#define SM_SMALL_PAGE 256 +#define SM_SMALL_OOB_SIZE 8 + + +extern int sm_register_device(struct mtd_info *mtd); + + +inline int sm_sector_valid(struct sm_oob *oob) +{ + return hweight16(oob->data_status) >= 5; +} + +inline int sm_block_valid(struct sm_oob *oob) +{ + return hweight16(oob->block_status) >= 7; +} + +inline int sm_block_erased(struct sm_oob *oob) +{ + static const u32 erased_pattern[4] = { + 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF, 0xFFFFFFFF }; + + /* First test for erased block */ + if (!memcmp(oob, erased_pattern, sizeof(*oob))) + return 1; + return 0; +} -- 1.6.3.3
| |