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>
This commit is contained in:
Boris Brezillon 2018-01-09 09:50:34 +01:00
parent d020fc8e50
commit 24ff129222
5 changed files with 33 additions and 188 deletions

View File

@ -990,36 +990,6 @@ static int doc_read_oob(struct mtd_info *mtd, loff_t from,
goto out;
}
/**
* doc_read - Read bytes from flash
* @mtd: the device
* @from: the offset from first block and first page, in bytes, aligned on page
* size
* @len: the number of bytes to read (must be a multiple of 4)
* @retlen: the number of bytes actually read
* @buf: the filled in buffer
*
* Reads flash memory pages. This function does not read the OOB chunk, but only
* the page data.
*
* Returns 0 if read successful, of -EIO, -EINVAL if an error occurred
*/
static int doc_read(struct mtd_info *mtd, loff_t from, size_t len,
size_t *retlen, u_char *buf)
{
struct mtd_oob_ops ops;
size_t ret;
memset(&ops, 0, sizeof(ops));
ops.datbuf = buf;
ops.len = len;
ops.mode = MTD_OPS_AUTO_OOB;
ret = doc_read_oob(mtd, from, &ops);
*retlen = ops.retlen;
return ret;
}
static int doc_reload_bbt(struct docg3 *docg3)
{
int block = DOC_LAYOUT_BLOCK_BBT;
@ -1513,39 +1483,6 @@ static int doc_write_oob(struct mtd_info *mtd, loff_t ofs,
return ret;
}
/**
* doc_write - Write a buffer to the chip
* @mtd: the device
* @to: the offset from first block and first page, in bytes, aligned on page
* size
* @len: the number of bytes to write (must be a full page size, ie. 512)
* @retlen: the number of bytes actually written (0 or 512)
* @buf: the buffer to get bytes from
*
* Writes data to the chip.
*
* Returns 0 if write successful, -EIO if write error
*/
static int doc_write(struct mtd_info *mtd, loff_t to, size_t len,
size_t *retlen, const u_char *buf)
{
struct docg3 *docg3 = mtd->priv;
int ret;
struct mtd_oob_ops ops;
doc_dbg("doc_write(to=%lld, len=%zu)\n", to, len);
ops.datbuf = (char *)buf;
ops.len = len;
ops.mode = MTD_OPS_PLACE_OOB;
ops.oobbuf = NULL;
ops.ooblen = 0;
ops.ooboffs = 0;
ret = doc_write_oob(mtd, to, &ops);
*retlen = ops.retlen;
return ret;
}
static struct docg3 *sysfs_dev2docg3(struct device *dev,
struct device_attribute *attr)
{
@ -1866,8 +1803,6 @@ static int __init doc_set_driver_info(int chip_id, struct mtd_info *mtd)
mtd->writebufsize = mtd->writesize = DOC_LAYOUT_PAGE_SIZE;
mtd->oobsize = DOC_LAYOUT_OOB_SIZE;
mtd->_erase = doc_erase;
mtd->_read = doc_read;
mtd->_write = doc_write;
mtd->_read_oob = doc_read_oob;
mtd->_write_oob = doc_write_oob;
mtd->_block_isbad = doc_block_isbad;

View File

@ -1058,7 +1058,20 @@ 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)
@ -1073,11 +1086,25 @@ 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;
ledtrig_mtd_activity();
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

@ -437,8 +437,10 @@ static struct mtd_part *allocate_partition(struct mtd_info *parent,
parent->dev.parent;
slave->mtd.dev.of_node = part->of_node;
slave->mtd._read = part_read;
slave->mtd._write = part_write;
if (parent->_read)
slave->mtd._read = part_read;
if (parent->_write)
slave->mtd._write = part_write;
if (parent->_panic_write)
slave->mtd._panic_write = part_panic_write;

View File

@ -2026,33 +2026,6 @@ static int nand_do_read_ops(struct mtd_info *mtd, loff_t from,
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
@ -2821,33 +2794,6 @@ 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
@ -4917,8 +4863,6 @@ int nand_scan_tail(struct mtd_info *mtd)
mtd->_erase = nand_erase;
mtd->_point = NULL;
mtd->_unpoint = NULL;
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

@ -1447,38 +1447,6 @@ static int onenand_read_oob_nolock(struct mtd_info *mtd, loff_t from,
return 0;
}
/**
* onenand_read - [MTD Interface] Read data from flash
* @param mtd MTD device structure
* @param from offset to read from
* @param len number of bytes to read
* @param retlen pointer to variable to store the number of read bytes
* @param buf the databuffer to put data
*
* Read with ecc
*/
static int onenand_read(struct mtd_info *mtd, loff_t from, size_t len,
size_t *retlen, u_char *buf)
{
struct onenand_chip *this = mtd->priv;
struct mtd_oob_ops ops = {
.len = len,
.ooblen = 0,
.datbuf = buf,
.oobbuf = NULL,
};
int ret;
onenand_get_device(mtd, FL_READING);
ret = ONENAND_IS_4KB_PAGE(this) ?
onenand_mlc_read_ops_nolock(mtd, from, &ops) :
onenand_read_ops_nolock(mtd, from, &ops);
onenand_release_device(mtd);
*retlen = ops.retlen;
return ret;
}
/**
* onenand_read_oob - [MTD Interface] Read main and/or out-of-band
* @param mtd: MTD device structure
@ -2128,35 +2096,6 @@ static int onenand_write_oob_nolock(struct mtd_info *mtd, loff_t to,
return ret;
}
/**
* onenand_write - [MTD Interface] write buffer to FLASH
* @param mtd MTD device structure
* @param to offset to write to
* @param len number of bytes to write
* @param retlen pointer to variable to store the number of written bytes
* @param buf the data to write
*
* Write with ECC
*/
static int onenand_write(struct mtd_info *mtd, loff_t to, size_t len,
size_t *retlen, const u_char *buf)
{
struct mtd_oob_ops ops = {
.len = len,
.ooblen = 0,
.datbuf = (u_char *) buf,
.oobbuf = NULL,
};
int ret;
onenand_get_device(mtd, FL_WRITING);
ret = onenand_write_ops_nolock(mtd, to, &ops);
onenand_release_device(mtd);
*retlen = ops.retlen;
return ret;
}
/**
* onenand_write_oob - [MTD Interface] NAND write data and/or out-of-band
* @param mtd: MTD device structure
@ -4038,8 +3977,6 @@ int onenand_scan(struct mtd_info *mtd, int maxchips)
mtd->_erase = onenand_erase;
mtd->_point = NULL;
mtd->_unpoint = NULL;
mtd->_read = onenand_read;
mtd->_write = onenand_write;
mtd->_read_oob = onenand_read_oob;
mtd->_write_oob = onenand_write_oob;
mtd->_panic_write = onenand_panic_write;