linux.git/drivers/mtd/mtdcore.c, branch v5.17

mtd: core: Fix a conflict between MTD and NVMEM on wp-gpios property

2022-02-21T16:59:25+00:00

Wp-gpios property can be used on NVMEM nodes and the same property can
be also used on MTD NAND nodes. In case of the wp-gpios property is
defined at NAND level node, the GPIO management is done at NAND driver
level. Write protect is disabled when the driver is probed or resumed
and is enabled when the driver is released or suspended.

When no partitions are defined in the NAND DT node, then the NAND DT node
will be passed to NVMEM framework. If wp-gpios property is defined in
this node, the GPIO resource is taken twice and the NAND controller
driver fails to probe.

A new Boolean flag named ignore_wp has been added in nvmem_config.
In case ignore_wp is set, it means that the GPIO is handled by the
provider. Lets set this flag in MTD layer to avoid the conflict on
wp_gpios property.

Fixes: 2a127da461a9 ("nvmem: add support for the write-protect pin")
Cc: stable@vger.kernel.org
Acked-by: Miquel Raynal 
Signed-off-by: Christophe Kerello 
Signed-off-by: Srinivas Kandagatla 
Link: https://lore.kernel.org/r/20220220151432.16605-3-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman

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: core: clear out unregistered devices a bit more

2021-12-03T13:27:19+00:00

This allows an MTD device that has been unregistered to be easily
re-registered later without triggering spurious "already registered"
warnings in mtd_device_parse_register() and add_mtd_device().

Signed-off-by: Zev Weiss 
Signed-off-by: Miquel Raynal 
Link: https://lore.kernel.org/linux-mtd/20211015185049.3318-1-zev@bewilderbeest.net

mtd: core: provide unique name for nvmem device

2021-12-03T13:27:19+00:00

If there is more than one mtd device which supports OTP, there will
be a kernel warning about duplicated sysfs entries and the probing will
fail. This is because the nvmem device name is not unique. Make it
unique by prepending the name of the mtd. E.g. before the name was
"user-otp", now it will be "mtd0-user-otp".

For reference the kernel splash is:
[    4.665531] sysfs: cannot create duplicate filename '/bus/nvmem/devices/user-otp'
[    4.673056] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.15.0-next-20211101+ #1296
[    4.680565] Hardware name: Kontron SMARC-sAL28 (Single PHY) on SMARC Eval 2.0 carrier (DT)
[    4.688856] Call trace:
[    4.691303]  dump_backtrace+0x0/0x1bc
[    4.694984]  show_stack+0x24/0x30
[    4.698306]  dump_stack_lvl+0x68/0x84
[    4.701980]  dump_stack+0x18/0x34
[    4.705302]  sysfs_warn_dup+0x70/0x90
[    4.708973]  sysfs_do_create_link_sd+0x144/0x150
[    4.713603]  sysfs_create_link+0x2c/0x50
[    4.717535]  bus_add_device+0x74/0x120
[    4.721293]  device_add+0x330/0x890
[    4.724791]  device_register+0x2c/0x40
[    4.728550]  nvmem_register+0x240/0x9f0
[    4.732398]  mtd_otp_nvmem_register+0xb0/0x10c
[    4.736854]  mtd_device_parse_register+0x28c/0x2b4
[    4.741659]  spi_nor_probe+0x20c/0x2e0
[    4.745418]  spi_mem_probe+0x78/0xbc
[    4.749001]  spi_probe+0x90/0xf0
[    4.752237]  really_probe.part.0+0xa4/0x320
..
[    4.873936] mtd mtd1: Failed to register OTP NVMEM device
[    4.894468] spi-nor: probe of spi0.0 failed with error -17

Fixes: 4b361cfa8624 ("mtd: core: add OTP nvmem provider support")
Signed-off-by: Michael Walle 
Signed-off-by: Miquel Raynal 
Link: https://lore.kernel.org/linux-mtd/20211104134843.2642800-1-michael@walle.cc

Merge tag 'mtd/for-5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/mtd/linux

2021-11-08T19:37:39+00:00

Pull mtd updates from Miquel Raynal:
 "Core:
   - Remove obsolete macros only used by the old nand_ecclayout struct
   - Don't remove debugfs directory if device is in use
   - MAINTAINERS:
      - Add entry for Qualcomm NAND controller driver
      - Update the devicetree documentation path of hyperbus

  MTD devices:
   - block2mtd:
      - Add support for an optional custom MTD label
      - Minor refactor to avoid hard coded constant
   - mtdswap: Remove redundant assignment of pointer eb

  CFI:
   - Fixup CFI on ixp4xx

  Raw NAND controller drivers:
   - Arasan:
      - Prevent an unsupported configuration
   - Xway, Socrates: plat_nand, Pasemi, Orion, mpc5121, GPIO, Au1550nd,
     AMS-Delta:
      - Keep the driver compatible with on-die ECC engines
   - cs553x, lpc32xx_slc, ndfc, sharpsl, tmio, txx9ndfmc:
      - Revert the commits: "Fix external use of SW Hamming ECC helper"
      - And let callers use the bare Hamming helpers
   - Fsmc: Fix use of SM ORDER
   - Intel:
      - Fix potential buffer overflow in probe
   - xway, vf610, txx9ndfm, tegra, stm32, plat_nand, oxnas, omap, mtk,
     hisi504, gpmi, gpio, denali, bcm6368, atmel:
      - Make use of the helper function devm_platform_ioremap_resource{,byname}()

  Onenand drivers:
   - Samsung: Drop Exynos4 and describe driver in KConfig

  Raw NAND chip drivers:
   - Hynix: Add support for H27UCG8T2ETR-BC MLC NAND

  SPI NOR core:
   - Add spi-nor device tree binding under SPI NOR maintainers

  SPI NOR manufacturer drivers:
   - Enable locking for n25q128a13

  SPI NOR controller drivers:
   - Use devm_platform_ioremap_resource_byname()"

* tag 'mtd/for-5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/mtd/linux: (50 commits)
  mtd: core: don't remove debugfs directory if device is in use
  MAINTAINERS: Update the devicetree documentation path of hyperbus
  mtd: block2mtd: add support for an optional custom MTD label
  mtd: block2mtd: minor refactor to avoid hard coded constant
  mtd: fixup CFI on ixp4xx
  mtd: rawnand: arasan: Prevent an unsupported configuration
  MAINTAINERS: Add entry for Qualcomm NAND controller driver
  mtd: rawnand: hynix: Add support for H27UCG8T2ETR-BC MLC NAND
  mtd: rawnand: xway: Keep the driver compatible with on-die ECC engines
  mtd: rawnand: socrates: Keep the driver compatible with on-die ECC engines
  mtd: rawnand: plat_nand: Keep the driver compatible with on-die ECC engines
  mtd: rawnand: pasemi: Keep the driver compatible with on-die ECC engines
  mtd: rawnand: orion: Keep the driver compatible with on-die ECC engines
  mtd: rawnand: mpc5121: Keep the driver compatible with on-die ECC engines
  mtd: rawnand: gpio: Keep the driver compatible with on-die ECC engines
  mtd: rawnand: au1550nd: Keep the driver compatible with on-die ECC engines
  mtd: rawnand: ams-delta: Keep the driver compatible with on-die ECC engines
  Revert "mtd: rawnand: cs553x: Fix external use of SW Hamming ECC helper"
  Revert "mtd: rawnand: lpc32xx_slc: Fix external use of SW Hamming ECC helper"
  Revert "mtd: rawnand: ndfc: Fix external use of SW Hamming ECC helper"
  ...

mtd: call bdi_unregister explicitly

2021-11-06T20:30:34+00:00

Call bdi_unregister explicitly instead of relying on the automatic
unregistration.

Link: https://lkml.kernel.org/r/20211021124441.668816-3-hch@lst.de
Signed-off-by: Christoph Hellwig 
Reviewed-by: Jan Kara 
Cc: Miquel Raynal 
Cc: Richard Weinberger 
Cc: Vignesh Raghavendra 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mtd: core: don't remove debugfs directory if device is in use

2021-10-15T10:30:40+00:00

Previously, if del_mtd_device() failed with -EBUSY due to a non-zero
usecount, a subsequent call to attempt the deletion again would try to
remove a debugfs directory that had already been removed and panic.
With this change the second call can instead proceed safely.

Fixes: e8e3edb95ce6 ("mtd: create per-device and module-scope debugfs entries")
Signed-off-by: Zev Weiss 
Signed-off-by: Miquel Raynal 
Link: https://lore.kernel.org/linux-mtd/20211014203953.5424-1-zev@bewilderbeest.net

mtd: core: handle flashes without OTP gracefully

2021-07-15T22:49:20+00:00

There are flash drivers which registers the OTP callbacks although the
flash doesn't support OTP regions and return -ENODATA for these
callbacks if there is no OTP. If this happens, the probe of the whole
flash will fail. Fix it by handling the ENODATA return code and skip
the OTP region nvmem setup.

Fixes: 4b361cfa8624 ("mtd: core: add OTP nvmem provider support")
Reported-by: Guenter Roeck 
Signed-off-by: Michael Walle 
Tested-by: Guenter Roeck 
Signed-off-by: Miquel Raynal 
Link: https://lore.kernel.org/linux-mtd/20210707135359.32398-1-michael@walle.cc

mtd: core: use MTD_DEVICE_ATTR_RO/RW() helper macros

2021-06-11T18:42:57+00:00

Use MTD_DEVICE_ATTR_RO/RW() helper macros instead of plain DEVICE_ATTR(),
which makes the code a bit shorter and easier to read.

Signed-off-by: Zhen Lei 
Signed-off-by: Miquel Raynal 
Link: https://lore.kernel.org/linux-mtd/20210603125323.12142-3-thunder.leizhen@huawei.com

mtd: core: add MTD_DEVICE_ATTR_RO/RW() helper macros

2021-06-11T18:42:50+00:00

Compared with the definition of DEVICE_ATTR_RO/RW(), the read and write
function names of the sysfs attribute have an additional "mtd_" prefix.

Signed-off-by: Zhen Lei 
Signed-off-by: Miquel Raynal 
Link: https://lore.kernel.org/linux-mtd/20210603125323.12142-2-thunder.leizhen@huawei.com