[PATCH v3 4/4] mtd: rawnand: remove suspended check

From: Sean Nyekjaer
Date: Mon Oct 25 2021 - 05:28:08 EST


Access is protected in upper MTD layer when MTD devices are suspended.

Commit ("mtd: core: protect access to MTD devices while in suspend")
introduces access protection, so it's safe to remove suspended checks.

Reviewed-by: Miquel Raynal <miquel.raynal@xxxxxxxxxxx>
Signed-off-by: Sean Nyekjaer <sean@xxxxxxxxxx>
---
drivers/mtd/nand/raw/nand_base.c | 52 ++++++++------------------------
include/linux/mtd/rawnand.h | 5 +--
2 files changed, 14 insertions(+), 43 deletions(-)

diff --git a/drivers/mtd/nand/raw/nand_base.c b/drivers/mtd/nand/raw/nand_base.c
index 3d6c6e880520..aa2874ae3c4a 100644
--- a/drivers/mtd/nand/raw/nand_base.c
+++ b/drivers/mtd/nand/raw/nand_base.c
@@ -332,19 +332,11 @@ static int nand_isbad_bbm(struct nand_chip *chip, loff_t ofs)
* @chip: NAND chip structure
*
* Lock the device and its controller for exclusive access
- *
- * Return: -EBUSY if the chip has been suspended, 0 otherwise
*/
-static int nand_get_device(struct nand_chip *chip)
+static void nand_get_device(struct nand_chip *chip)
{
mutex_lock(&chip->lock);
- if (chip->suspended) {
- mutex_unlock(&chip->lock);
- return -EBUSY;
- }
mutex_lock(&chip->controller->lock);
-
- return 0;
}

/**
@@ -573,10 +565,7 @@ static int nand_block_markbad_lowlevel(struct nand_chip *chip, loff_t ofs)
nand_erase_nand(chip, &einfo, 0);

/* Write bad block marker to OOB */
- ret = nand_get_device(chip);
- if (ret)
- return ret;
-
+ nand_get_device(chip);
ret = nand_markbad_bbm(chip, ofs);
nand_release_device(chip);
}
@@ -3756,9 +3745,7 @@ static int nand_read_oob(struct mtd_info *mtd, loff_t from,
ops->mode != MTD_OPS_RAW)
return -ENOTSUPP;

- ret = nand_get_device(chip);
- if (ret)
- return ret;
+ nand_get_device(chip);

if (!ops->datbuf)
ret = nand_do_read_oob(chip, from, ops);
@@ -4345,13 +4332,11 @@ static int nand_write_oob(struct mtd_info *mtd, loff_t to,
struct mtd_oob_ops *ops)
{
struct nand_chip *chip = mtd_to_nand(mtd);
- int ret;
+ int ret = 0;

ops->retlen = 0;

- ret = nand_get_device(chip);
- if (ret)
- return ret;
+ nand_get_device(chip);

switch (ops->mode) {
case MTD_OPS_PLACE_OOB:
@@ -4410,10 +4395,8 @@ int nand_erase_nand(struct nand_chip *chip, struct erase_info *instr,
if (nand_region_is_secured(chip, instr->addr, instr->len))
return -EIO;

- /* Grab the lock and see if the device is available */
- ret = nand_get_device(chip);
- if (ret)
- return ret;
+ /* Grab the lock */
+ nand_get_device(chip);

/* Shift to get first page */
page = (int)(instr->addr >> chip->page_shift);
@@ -4499,8 +4482,8 @@ static void nand_sync(struct mtd_info *mtd)

pr_debug("%s: called\n", __func__);

- /* Grab the lock and see if the device is available */
- WARN_ON(nand_get_device(chip));
+ /* Grab the lock */
+ nand_get_device(chip);
/* Release it and go back */
nand_release_device(chip);
}
@@ -4517,9 +4500,7 @@ static int nand_block_isbad(struct mtd_info *mtd, loff_t offs)
int ret;

/* Select the NAND device */
- ret = nand_get_device(chip);
- if (ret)
- return ret;
+ nand_get_device(chip);

nand_select_target(chip, chipnr);

@@ -4565,8 +4546,6 @@ static int nand_suspend(struct mtd_info *mtd)
mutex_lock(&chip->lock);
if (chip->ops.suspend)
ret = chip->ops.suspend(chip);
- if (!ret)
- chip->suspended = 1;
mutex_unlock(&chip->lock);

return ret;
@@ -4580,15 +4559,10 @@ static void nand_resume(struct mtd_info *mtd)
{
struct nand_chip *chip = mtd_to_nand(mtd);

+
mutex_lock(&chip->lock);
- if (chip->suspended) {
- if (chip->ops.resume)
- chip->ops.resume(chip);
- chip->suspended = 0;
- } else {
- pr_err("%s called for a chip which is not in suspended state\n",
- __func__);
- }
+ if (chip->ops.resume)
+ chip->ops.resume(chip);
mutex_unlock(&chip->lock);
}

diff --git a/include/linux/mtd/rawnand.h b/include/linux/mtd/rawnand.h
index b2f9dd3cbd69..1198a6548912 100644
--- a/include/linux/mtd/rawnand.h
+++ b/include/linux/mtd/rawnand.h
@@ -1237,9 +1237,7 @@ struct nand_secure_region {
* @pagecache.page: Page number currently in the cache. -1 means no page is
* currently cached
* @buf_align: Minimum buffer alignment required by a platform
- * @lock: Lock protecting the suspended field. Also used to serialize accesses
- * to the NAND device
- * @suspended: Set to 1 when the device is suspended, 0 when it's not
+ * @lock: Lock to serialize accesses to the NAND device
* @cur_cs: Currently selected target. -1 means no target selected, otherwise we
* should always have cur_cs >= 0 && cur_cs < nanddev_ntargets().
* NAND Controller drivers should not modify this value, but they're
@@ -1293,7 +1291,6 @@ struct nand_chip {

/* Internals */
struct mutex lock;
- unsigned int suspended : 1;
int cur_cs;
int read_retries;
struct nand_secure_region *secure_regions;
--
2.33.0