From mboxrd@z Thu Jan 1 00:00:00 1970 From: lee.jones@linaro.org (Lee Jones) Date: Tue, 25 Mar 2014 08:19:59 +0000 Subject: [RFC 42/47] mtd: nand: stm_nand_bch: add read and write OOB (BCH) In-Reply-To: <1395735604-26706-1-git-send-email-lee.jones@linaro.org> References: <1395735604-26706-1-git-send-email-lee.jones@linaro.org> Message-ID: <1395735604-26706-43-git-send-email-lee.jones@linaro.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Provide functions to read and write to the Out-Of-Bounds (OOB) area. Signed-off-by: Lee Jones --- drivers/mtd/nand/stm_nand_bch.c | 107 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 107 insertions(+) diff --git a/drivers/mtd/nand/stm_nand_bch.c b/drivers/mtd/nand/stm_nand_bch.c index 38658b8..389ccee 100644 --- a/drivers/mtd/nand/stm_nand_bch.c +++ b/drivers/mtd/nand/stm_nand_bch.c @@ -1218,6 +1218,111 @@ static int flex_do_write_ops(struct nandi_controller *nandi, return 0; } +static char *mtd_oob_mode_strs[] = {"PLACE", "AUTO", "RAW"}; + +static int bch_mtd_read_and_write_oob(struct mtd_info *mtd, loff_t tofrom, + struct mtd_oob_ops *ops, + bool read) +{ + struct nand_chip *chip = mtd->priv; + struct nandi_controller *nandi = chip->priv; + uint32_t page_mask = mtd->writesize - 1; + int ret; + + dev_dbg(nandi->dev, "%s: 0x%012llx [page = %u, oob = %u mode = %s]\n", + __func__, tofrom, + (ops->datbuf ? ops->len : 0), + (ops->oobbuf ? ops->ooblen : 0), + mtd_oob_mode_strs[ops->mode]); + + if (!ops->oobbuf && ops->mode != MTD_OPS_RAW) { + if (read) + return mtd_read(mtd, tofrom, ops->len, + &ops->retlen, ops->datbuf); + else + return mtd_write(mtd, tofrom, ops->len, + &ops->retlen, ops->datbuf); + } + + ops->oobretlen = 0; + ops->retlen = 0; + + /* + * We report OOB as unavailable (i.e. oobavail = 0), therefore nothing + * should call this + */ + if (ops->oobbuf && ops->mode == MTD_OPS_AUTO_OOB) + return -ENOTSUPP; + + /* Not currently supported by MTD */ + if (ops->datbuf && ops->oobbuf && ops->mode == MTD_OPS_PLACE_OOB) + return -ENOTSUPP; + + /* Do not allow oob reads with ooboffs */ + if (ops->oobbuf && ops->ooboffs) + return -ENOTSUPP; + + /* Do not allow reads past end of device */ + if (ops->datbuf && (tofrom + ops->len) > mtd->size) { + dev_err(nandi->dev, "attempt %s beyond end of device\n", + read ? "read" : "write"); + return -EINVAL; + } + + if (ops->oobbuf && + (tofrom + mtd->writesize * (ops->ooblen / mtd->oobsize)) + > mtd->size) { + dev_err(nandi->dev, "attempt %s beyond end of device\n", + read ? "read" : "write"); + return -EINVAL; + } + + /* Do not allow non-aligned reads/writes */ + if ((tofrom & page_mask) || + (ops->datbuf && (ops->len & page_mask)) || + (ops->oobbuf && (ops->ooblen % mtd->oobsize))) { + dev_err(nandi->dev, "attempt to %s non-aligned data\n", + read ? "read" : "write"); + return -EINVAL; + } + + /* Do not allow inconsistent data and oob lengths */ + if (ops->datbuf && ops->oobbuf && + (ops->len / mtd->writesize != ops->ooblen / mtd->oobsize)) { + dev_err(nandi->dev, + "data length inconsistent with oob length\n"); + return -EINVAL; + } + + nand_get_device(mtd, read ? FL_READING : FL_WRITING); + + if (!read && flex_check_wp(nandi)) { + dev_dbg(nandi->dev, "device is write-protected\n"); + return -EIO; + } + + if (read) + ret = flex_do_read_ops(nandi, tofrom, ops); + else + ret = flex_do_write_ops(nandi, tofrom, ops); + + nand_release_device(mtd); + + return ret; +} + +static int bch_mtd_read_oob(struct mtd_info *mtd, loff_t from, + struct mtd_oob_ops *ops) +{ + return bch_mtd_read_and_write_oob(mtd, from, ops, true); +} + +static int bch_mtd_write_oob(struct mtd_info *mtd, loff_t to, + struct mtd_oob_ops *ops) +{ + return bch_mtd_read_and_write_oob(mtd, to, ops, false); +} + static int bch_mtd_block_isbad(struct mtd_info *mtd, loff_t offs) { struct nand_chip *chip = mtd->priv; @@ -1454,6 +1559,8 @@ static void nandi_set_mtd_defaults(struct nandi_controller *nandi, mtd->subpage_sft = 0; mtd->_erase = bch_mtd_erase; + mtd->_read_oob = bch_mtd_read_oob; + mtd->_write_oob = bch_mtd_write_oob; mtd->_block_isbad = bch_mtd_block_isbad; mtd->_block_markbad = bch_mtd_block_markbad; -- 1.8.3.2