[PATCH v3 4/4] mtd: Fallback to ->_read/write_oob() when ->_read/write() is missing
Boris Brezillon
boris.brezillon at free-electrons.com
Fri Dec 15 04:39:54 PST 2017
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 at free-electrons.com>
Acked-by: Robert Jarzmik <robert.jarzmik at free.fr>
Acked-by: Brian Norris <computersforpeace at gmail.com>
---
Changes in v3:
- none
Changes in v2:
- none
---
drivers/mtd/devices/docg3.c | 65 --------------------------------------
drivers/mtd/mtdcore.c | 31 ++++++++++++++++--
drivers/mtd/nand/nand_base.c | 56 --------------------------------
drivers/mtd/onenand/onenand_base.c | 63 ------------------------------------
4 files changed, 29 insertions(+), 186 deletions(-)
diff --git a/drivers/mtd/devices/docg3.c b/drivers/mtd/devices/docg3.c
index 0806f72102c0..5fb5e93d1547 100644
--- a/drivers/mtd/devices/docg3.c
+++ b/drivers/mtd/devices/docg3.c
@@ -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;
diff --git a/drivers/mtd/mtdcore.c b/drivers/mtd/mtdcore.c
index 642c35dde686..d7ab091b36b2 100644
--- a/drivers/mtd/mtdcore.c
+++ b/drivers/mtd/mtdcore.c
@@ -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);
diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c
index 6135d007a068..889ceadbf607 100644
--- a/drivers/mtd/nand/nand_base.c
+++ b/drivers/mtd/nand/nand_base.c
@@ -2027,33 +2027,6 @@ static int nand_do_read_ops(struct mtd_info *mtd, loff_t from,
}
/**
- * 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
* @chip: nand chip info structure
@@ -2822,33 +2795,6 @@ static int panic_nand_write(struct mtd_info *mtd, loff_t to, size_t len,
}
/**
- * 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
* @to: offset to write to
@@ -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;
diff --git a/drivers/mtd/onenand/onenand_base.c b/drivers/mtd/onenand/onenand_base.c
index 1a6d0e367b89..050ba8a87543 100644
--- a/drivers/mtd/onenand/onenand_base.c
+++ b/drivers/mtd/onenand/onenand_base.c
@@ -1448,38 +1448,6 @@ static int onenand_read_oob_nolock(struct mtd_info *mtd, loff_t from,
}
/**
- * 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
* @param from: offset to read from
@@ -2129,35 +2097,6 @@ static int onenand_write_oob_nolock(struct mtd_info *mtd, loff_t to,
}
/**
- * 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
* @param to: offset to write
@@ -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;
--
2.11.0
More information about the linux-mtd
mailing list