linux-toradex.git/include/linux/mtd/mtd.h, branch v6.0-rc1

mtd: fix 'part' field data corruption in mtd_info

2022-04-21T07:29:05+00:00

Commit 46b5889cc2c5 ("mtd: implement proper partition handling")
started using "mtd_get_master_ofs()" in mtd callbacks to determine
memory offsets by means of 'part' field from mtd_info, what previously
was smashed accessing 'master' field in the mtd_set_dev_defaults() method.
That provides wrong offset what causes hardware access errors.

Just make 'part', 'master' as separate fields, rather than using
union type to avoid 'part' data corruption when mtd_set_dev_defaults()
is called.

Fixes: 46b5889cc2c5 ("mtd: implement proper partition handling")
Signed-off-by: Oleksandr Ocheretnyi 
Signed-off-by: Miquel Raynal 
Link: https://lore.kernel.org/linux-mtd/20220417184649.449289-1-oocheret@cisco.com

mtd: core: Remove partid and partname debugfs files

2022-03-14T16:01:58+00:00

partid and partname debugfs files were used just by SPI NOR, but they were
replaced by sysfs entries. Since these debugfs files are no longer used in
mtd, remove dead code. The directory is kept as it is used by nandsim,
mtdswap and docg3.

Signed-off-by: Tudor Ambarus 
Reviewed-by: Pratyush Yadav 
Signed-off-by: Miquel Raynal 
Link: https://lore.kernel.org/linux-mtd/20220225144656.634682-1-tudor.ambarus@microchip.com

mtd: Replace the expert mode symbols with a single helper

2022-02-07T15:36:11+00:00

Reduce the number of exported symbols by replacing:
- mtd_expert_analysis_warning (the error string)
- mtd_expert_analysis_mode (the boolean)
with a single helper:
- mtd_check_expert_analysis_mode

Calling this helper will both check/return the content of the internal
boolean -which is not exported anymore- and as well conditionally
WARN_ONCE() the user, like it was done before.

While on this function, make the error string local to the helper and
set it const. Only export this helper when CONFIG_DEBUG_FS is defined to
limit the growth of the Linux kernel size only for a debug feature on
production kernels.

Mechanically update all the consumers.

Suggested-by: Geert Uytterhoeven 
Signed-off-by: Miquel Raynal 
Link: https://lore.kernel.org/linux-mtd/20220128113414.1121924-1-miquel.raynal@bootlin.com

mtd: Introduce an expert mode for forensics and debugging purposes

2021-12-09T16:51:59+00:00

When developping NAND controller drivers or when debugging filesystem
corruptions, it is quite common to need hacking locally into the
MTD/NAND core in order to get access to the content of the bad
blocks. Instead of having multiple implementations out there let's
provide a simple yet effective specific MTD-wide debugfs entry to fully
disable these checks on purpose.

A warning is added to inform the user when this mode gets enabled.

Signed-off-by: Miquel Raynal 
Link: https://lore.kernel.org/linux-mtd/20211118114659.1282855-1-miquel.raynal@bootlin.com

mtd: Remove obsolete macros only used by the old nand_ecclayout struct

2021-09-14T17:34:28+00:00

All uses of MTD_MAX_{OOBFREE,ECCPOS}_ENTRIES_LARGE have been removed as
commit ef5eeea6e911 ("mtd: nand: brcm: switch to mtd_ooblayout_ops") and
commit aab616e31d1c ("mtd: kill the nand_ecclayout struct") replaced
struct nand_ecclayout by the new mtd_ooblayout_ops interface. Remove
these two macros therefore.

Reported-by: Yi Yang 
Signed-off-by: GONG, Ruiqi 
Signed-off-by: Miquel Raynal 
Link: https://lore.kernel.org/linux-mtd/20210830083356.31702-1-gongruiqi1@huawei.com

mtd: core: add OTP nvmem provider support

2021-05-10T10:42:55+00:00

Flash OTP regions can already be read via user space. Some boards have
their serial number or MAC addresses stored in the OTP regions. Add
support for them being a (read-only) nvmem provider.

The API to read the OTP data is already in place. It distinguishes
between factory and user OTP, thus there are up to two different
providers.

Signed-off-by: Michael Walle 
Signed-off-by: Miquel Raynal 
Link: https://lore.kernel.org/linux-mtd/20210424110608.15748-6-michael@walle.cc

mtd: core: Constify buf in mtd_write_user_prot_reg()

2021-04-16T18:30:54+00:00

The write buffer comes from user and should be const.
Constify write buffer in mtd core and across all _write_user_prot_reg()
users. cfi_cmdset_{0001, 0002} and onenand_base will pay the cost of an
explicit cast to discard the const qualifier since the beginning, since
they are using an otp_op_t function prototype that is used for both reads
and writes. mtd_dataflash and SPI NOR will benefit of the const buffer
because they are using different paths for writes and reads.

Signed-off-by: Tudor Ambarus 
Signed-off-by: Miquel Raynal 
Link: https://lore.kernel.org/linux-mtd/20210403060931.7119-1-tudor.ambarus@microchip.com

mtd: add OTP (one-time-programmable) erase ioctl

2021-03-28T17:24:54+00:00

This may sound like a contradiction but some SPI-NOR flashes really
support erasing their OTP region until it is finally locked. Having the
possibility to erase an OTP region might come in handy during
development.

The ioctl argument follows the OTPLOCK style.

Signed-off-by: Michael Walle 
Acked-by: Vignesh Raghavendra 
Signed-off-by: Miquel Raynal 
Link: https://lore.kernel.org/linux-mtd/20210303201819.2752-1-michael@walle.cc

mtd: char: Get rid of Big MTD Lock

2021-03-11T08:37:49+00:00

Get rid of central chrdev MTD lock, which prevents simultaneous operations
on completely independent physical MTD chips. Replace it with newly
introduced per-master mutex.

Signed-off-by: Alexander Sverdlin 
Signed-off-by: Miquel Raynal 
Link: https://lore.kernel.org/linux-mtd/20210217211845.43364-2-alexander.sverdlin@nokia.com

mtd: Add support for emulated SLC mode on MLC NANDs

2020-05-11T07:51:41+00:00

MLC NANDs can be made a bit more reliable if we only program the lower
page of each pair. At least, this solves the paired-pages corruption
issue.

Signed-off-by: Boris Brezillon 
Signed-off-by: Miquel Raynal 
Link: https://lore.kernel.org/linux-mtd/20200503155341.16712-5-miquel.raynal@bootlin.com