mtd: Fallback to ->_read/write_oob() when ->_read/write() is missing

Some MTD sublayers/drivers are implementing ->_read/write_oob() and
provide dummy wrappers for their ->_read/write() implementations.
Let the core handle this case instead of duplicating the logic.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Acked-by: Robert Jarzmik <robert.jarzmik@free.fr>
Acked-by: Brian Norris <computersforpeace@gmail.com>
Reviewed-by: Miquel Raynal <miquel.raynal@free-electrons.com>
Tested-by: Ladislav Michl <ladis@linux-mips.org>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: Jagan Teki <jagan@openedev.com>
This commit is contained in:
Boris Brezillon 2018-08-16 17:29:59 +02:00 committed by Jagan Teki
parent 9dc8d155d4
commit 596cf083da
4 changed files with 33 additions and 62 deletions

View File

@ -937,7 +937,20 @@ int mtd_read(struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen,
* representing the maximum number of bitflips that were corrected on
* any one ecc region (if applicable; zero otherwise).
*/
ret_code = mtd->_read(mtd, from, len, retlen, buf);
if (mtd->_read) {
ret_code = mtd->_read(mtd, from, len, retlen, buf);
} else if (mtd->_read_oob) {
struct mtd_oob_ops ops = {
.len = len,
.datbuf = buf,
};
ret_code = mtd->_read_oob(mtd, from, &ops);
*retlen = ops.retlen;
} else {
return -ENOTSUPP;
}
if (unlikely(ret_code < 0))
return ret_code;
if (mtd->ecc_strength == 0)
@ -952,10 +965,24 @@ int mtd_write(struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen,
*retlen = 0;
if (to < 0 || to > mtd->size || len > mtd->size - to)
return -EINVAL;
if (!mtd->_write || !(mtd->flags & MTD_WRITEABLE))
if ((!mtd->_write && !mtd->_write_oob) ||
!(mtd->flags & MTD_WRITEABLE))
return -EROFS;
if (!len)
return 0;
if (!mtd->_write) {
struct mtd_oob_ops ops = {
.len = len,
.datbuf = (u8 *)buf,
};
int ret;
ret = mtd->_write_oob(mtd, to, &ops);
*retlen = ops.retlen;
return ret;
}
return mtd->_write(mtd, to, len, retlen, buf);
}
EXPORT_SYMBOL_GPL(mtd_write);

View File

@ -417,8 +417,10 @@ static struct mtd_part *allocate_partition(struct mtd_info *master,
slave->mtd.dev.parent = master->dev.parent;
#endif
slave->mtd._read = part_read;
slave->mtd._write = part_write;
if (master->_read)
slave->mtd._read = part_read;
if (master->_write)
slave->mtd._write = part_write;
if (master->_panic_write)
slave->mtd._panic_write = part_panic_write;

View File

@ -1863,33 +1863,6 @@ read_retry:
return max_bitflips;
}
/**
* nand_read - [MTD Interface] MTD compatibility function for nand_do_read_ecc
* @mtd: MTD device structure
* @from: offset to read from
* @len: number of bytes to read
* @retlen: pointer to variable to store the number of read bytes
* @buf: the databuffer to put data
*
* Get hold of the chip and call nand_do_read.
*/
static int nand_read(struct mtd_info *mtd, loff_t from, size_t len,
size_t *retlen, uint8_t *buf)
{
struct mtd_oob_ops ops;
int ret;
nand_get_device(mtd, FL_READING);
memset(&ops, 0, sizeof(ops));
ops.len = len;
ops.datbuf = buf;
ops.mode = MTD_OPS_PLACE_OOB;
ret = nand_do_read_ops(mtd, from, &ops);
*retlen = ops.retlen;
nand_release_device(mtd);
return ret;
}
/**
* nand_read_oob_std - [REPLACEABLE] the most common OOB data read function
* @mtd: mtd info structure
@ -2674,33 +2647,6 @@ static int panic_nand_write(struct mtd_info *mtd, loff_t to, size_t len,
return ret;
}
/**
* nand_write - [MTD Interface] NAND write with ECC
* @mtd: MTD device structure
* @to: offset to write to
* @len: number of bytes to write
* @retlen: pointer to variable to store the number of written bytes
* @buf: the data to write
*
* NAND write with ECC.
*/
static int nand_write(struct mtd_info *mtd, loff_t to, size_t len,
size_t *retlen, const uint8_t *buf)
{
struct mtd_oob_ops ops;
int ret;
nand_get_device(mtd, FL_WRITING);
memset(&ops, 0, sizeof(ops));
ops.len = len;
ops.datbuf = (uint8_t *)buf;
ops.mode = MTD_OPS_PLACE_OOB;
ret = nand_do_write_ops(mtd, to, &ops);
*retlen = ops.retlen;
nand_release_device(mtd);
return ret;
}
/**
* nand_do_write_oob - [MTD Interface] NAND write out-of-band
* @mtd: MTD device structure
@ -4620,8 +4566,6 @@ int nand_scan_tail(struct mtd_info *mtd)
mtd->flags = (chip->options & NAND_ROM) ? MTD_CAP_ROM :
MTD_CAP_NANDFLASH;
mtd->_erase = nand_erase;
mtd->_read = nand_read;
mtd->_write = nand_write;
mtd->_panic_write = panic_nand_write;
mtd->_read_oob = nand_read_oob;
mtd->_write_oob = nand_write_oob;

View File

@ -2656,8 +2656,6 @@ int onenand_probe(struct mtd_info *mtd)
mtd->flags = MTD_CAP_NANDFLASH;
mtd->_erase = onenand_erase;
mtd->_read = onenand_read;
mtd->_write = onenand_write;
mtd->_read_oob = onenand_read_oob;
mtd->_write_oob = onenand_write_oob;
mtd->_sync = onenand_sync;