From: Bean Huo <[email protected]> Add a new function nand_check_is_erased_page() in nand_base.c, which is used to check whether one programmable page is empty or already programmed.
Signed-off-by: Bean Huo <[email protected]> --- drivers/mtd/nand/raw/nand_base.c | 41 ++++++++++++++++++++++++++++++++ include/linux/mtd/rawnand.h | 2 ++ 2 files changed, 43 insertions(+) diff --git a/drivers/mtd/nand/raw/nand_base.c b/drivers/mtd/nand/raw/nand_base.c index 09ee490c08a9..2b9862d9979b 100644 --- a/drivers/mtd/nand/raw/nand_base.c +++ b/drivers/mtd/nand/raw/nand_base.c @@ -2646,6 +2646,47 @@ int nand_check_erased_ecc_chunk(void *data, int datalen, } EXPORT_SYMBOL(nand_check_erased_ecc_chunk); +/** + * nand_check_is_erased_page - check if this page is a empty page + * @chip: nand chip info structure + * @page_data: data buffer containing the data in the page being checked + * @oob: indicate if chip->oob_poi points to oob date of the page + * + * Returns true if this is an un-programmed page, false otherwise. + */ +int nand_check_is_erased_page(struct nand_chip *chip, u8 *page_data, bool oob) +{ + struct mtd_info *mtd = nand_to_mtd(chip); + int ret, i; + u8 *databuf, *eccbuf = NULL; + struct mtd_oob_region oobregion; + int datasize, eccbytes = 0; + + databuf = page_data; + datasize = chip->ecc.size; + + if (oob) { + mtd_ooblayout_ecc(mtd, 0, &oobregion); + eccbuf = chip->oob_poi + oobregion.offset; + eccbytes = chip->ecc.bytes; + } + max_bitflips = 0; + + for (i = 0; i < chip->ecc.steps; i++) { + ret = nand_check_erased_ecc_chunk(databuf, datasize, + eccbuf, eccbytes, + NULL, 0, chip->ecc.strength); + if (ret < 0) + return false; + + databuf += chip->ecc.size; + eccbuf += chip->ecc.bytes; + } + + return ret; +} +EXPORT_SYMBOL(nand_check_is_erased_page); + /** * nand_read_page_raw_notsupp - dummy read raw page function * @chip: nand chip info structure diff --git a/include/linux/mtd/rawnand.h b/include/linux/mtd/rawnand.h index 3d75e50e5b75..718ce81eb111 100644 --- a/include/linux/mtd/rawnand.h +++ b/include/linux/mtd/rawnand.h @@ -1337,6 +1337,8 @@ int nand_check_erased_ecc_chunk(void *data, int datalen, void *extraoob, int extraooblen, int threshold); +int nand_check_is_erased_page(struct nand_chip *chip, u8 *page_data, bool oob); + int nand_ecc_choose_conf(struct nand_chip *chip, const struct nand_ecc_caps *caps, int oobavail); -- 2.17.1
