diff options
Diffstat (limited to 'drivers/mtd')
| -rw-r--r-- | drivers/mtd/nand/nand_base.c | 57 |
1 files changed, 55 insertions, 2 deletions
diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c index b8c74cda762..d388c7f6fec 100644 --- a/drivers/mtd/nand/nand_base.c +++ b/drivers/mtd/nand/nand_base.c @@ -204,6 +204,51 @@ static void nand_select_chip(struct mtd_info *mtd, int chipnr) } /** + * nand_write_byte - [DEFAULT] write single byte to chip + * @mtd: MTD device structure + * @byte: value to write + * + * Default function to write a byte to I/O[7:0] + */ +static void nand_write_byte(struct mtd_info *mtd, uint8_t byte) +{ + struct nand_chip *chip = mtd->priv; + + chip->write_buf(mtd, &byte, 1); +} + +/** + * nand_write_byte16 - [DEFAULT] write single byte to a chip with width 16 + * @mtd: MTD device structure + * @byte: value to write + * + * Default function to write a byte to I/O[7:0] on a 16-bit wide chip. + */ +static void nand_write_byte16(struct mtd_info *mtd, uint8_t byte) +{ + struct nand_chip *chip = mtd->priv; + uint16_t word = byte; + + /* + * It's not entirely clear what should happen to I/O[15:8] when writing + * a byte. The ONFi spec (Revision 3.1; 2012-09-19, Section 2.16) reads: + * + * When the host supports a 16-bit bus width, only data is + * transferred at the 16-bit width. All address and command line + * transfers shall use only the lower 8-bits of the data bus. During + * command transfers, the host may place any value on the upper + * 8-bits of the data bus. During address transfers, the host shall + * set the upper 8-bits of the data bus to 00h. + * + * One user of the write_byte callback is nand_onfi_set_features. The + * four parameters are specified to be written to I/O[7:0], but this is + * neither an address nor a command transfer. Let's assume a 0 on the + * upper I/O lines is OK. + */ + chip->write_buf(mtd, (uint8_t *)&word, 2); +} + +/** * nand_write_buf - [DEFAULT] write buffer to chip * @mtd: MTD device structure * @buf: data buffer @@ -2769,6 +2814,7 @@ static int nand_onfi_set_features(struct mtd_info *mtd, struct nand_chip *chip, int addr, uint8_t *subfeature_param) { int status; + int i; if (!chip->onfi_version || !(le16_to_cpu(chip->onfi_params.opt_cmd) @@ -2776,7 +2822,9 @@ static int nand_onfi_set_features(struct mtd_info *mtd, struct nand_chip *chip, return -EINVAL; chip->cmdfunc(mtd, NAND_CMD_SET_FEATURES, addr, -1); - chip->write_buf(mtd, subfeature_param, ONFI_SUBFEATURE_PARAM_LEN); + for (i = 0; i < ONFI_SUBFEATURE_PARAM_LEN; ++i) + chip->write_byte(mtd, subfeature_param[i]); + status = chip->waitfunc(mtd, chip); if (status & NAND_STATUS_FAIL) return -EIO; @@ -2793,6 +2841,8 @@ static int nand_onfi_set_features(struct mtd_info *mtd, struct nand_chip *chip, static int nand_onfi_get_features(struct mtd_info *mtd, struct nand_chip *chip, int addr, uint8_t *subfeature_param) { + int i; + if (!chip->onfi_version || !(le16_to_cpu(chip->onfi_params.opt_cmd) & ONFI_OPT_CMD_SET_GET_FEATURES)) @@ -2802,7 +2852,8 @@ static int nand_onfi_get_features(struct mtd_info *mtd, struct nand_chip *chip, memset(subfeature_param, 0, ONFI_SUBFEATURE_PARAM_LEN); chip->cmdfunc(mtd, NAND_CMD_GET_FEATURES, addr, -1); - chip->read_buf(mtd, subfeature_param, ONFI_SUBFEATURE_PARAM_LEN); + for (i = 0; i < ONFI_SUBFEATURE_PARAM_LEN; ++i) + *subfeature_param++ = chip->read_byte(mtd); return 0; } @@ -2865,6 +2916,8 @@ static void nand_set_defaults(struct nand_chip *chip, int busw) chip->block_markbad = nand_default_block_markbad; if (!chip->write_buf || chip->write_buf == nand_write_buf) chip->write_buf = busw ? nand_write_buf16 : nand_write_buf; + if (!chip->write_byte || chip->write_byte == nand_write_byte) + chip->write_byte = busw ? nand_write_byte16 : nand_write_byte; if (!chip->read_buf || chip->read_buf == nand_read_buf) chip->read_buf = busw ? nand_read_buf16 : nand_read_buf; if (!chip->scan_bbt) |