[U-Boot] [PATCH v6 01/27] mtd: Fallback to ->_read/write_oob() when ->_read/write() is missing

Miquel Raynal
2018-08-01T08:18:22Z

From: Boris Brezillon <boris.brezillon@free-electrons.com>

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>
---
drivers/mtd/mtdcore.c | 31 ++++++++++++++++++--
drivers/mtd/mtdpart.c | 6 ++--
drivers/mtd/nand/nand_base.c | 56 -----------------------------------
drivers/mtd/onenand/onenand_base.c | 60 --------------------------------------
4 files changed, 33 insertions(+), 120 deletions(-)

diff --git a/drivers/mtd/mtdcore.c b/drivers/mtd/mtdcore.c
index 6217be2352..60ad28efd4 100644
--- a/drivers/mtd/mtdcore.c
+++ b/drivers/mtd/mtdcore.c
@@ -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);
diff --git a/drivers/mtd/mtdpart.c b/drivers/mtd/mtdpart.c
index f87c962205..ccbb1757ea 100644
--- a/drivers/mtd/mtdpart.c
+++ b/drivers/mtd/mtdpart.c
@@ -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;
diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c
index 64e4621aaa..0b58e15b03 100644
--- a/drivers/mtd/nand/nand_base.c
+++ b/drivers/mtd/nand/nand_base.c
@@ -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;
diff --git a/drivers/mtd/onenand/onenand_base.c b/drivers/mtd/onenand/onenand_base.c
index 86b1640357..080d8f0d94 100644
--- a/drivers/mtd/onenand/onenand_base.c
+++ b/drivers/mtd/onenand/onenand_base.c
@@ -1088,35 +1088,6 @@ static int onenand_read_oob_nolock(struct mtd_info *mtd, loff_t from,
return 0;
}

-/**
- * onenand_read - [MTD Interface] MTD compability function for onenand_read_ecc
- * @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
- *
- * This function simply calls onenand_read_ecc with oob buffer and oobsel = NULL
-*/
-int onenand_read(struct mtd_info *mtd, loff_t from, size_t len,
- size_t * retlen, u_char * buf)
-{
- struct mtd_oob_ops ops = {
- .len = len,
- .ooblen = 0,
- .datbuf = buf,
- .oobbuf = NULL,
- };
- int ret;
-
- onenand_get_device(mtd, FL_READING);
- ret = onenand_read_ops_nolock(mtd, from, &ops);
- onenand_release_device(mtd);
-
- *retlen = ops.retlen;
- return ret;
-}
-
/**
* onenand_read_oob - [MTD Interface] OneNAND read out-of-band
* @param mtd MTD device structure
@@ -1636,35 +1607,6 @@ static int onenand_write_oob_nolock(struct mtd_info *mtd, loff_t to,
return ret;
}

-/**
- * onenand_write - [MTD Interface] compability function for onenand_write_ecc
- * @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
- */
-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] OneNAND write out-of-band
* @param mtd MTD device structure
@@ -2656,8 +2598,6 @@ 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;
--
2.14.1