linux-stable.git/drivers/nvmem/core.c, branch v6.15

nvmem: core: update raw_len if the bit reading is required

2025-04-11T12:41:21+00:00

If NVMEM cell uses bit offset or specifies bit truncation, update
raw_len manually (following the cell->bytes update), ensuring that the
NVMEM access is still word-aligned.

Signed-off-by: Dmitry Baryshkov 
Signed-off-by: Srinivas Kandagatla 
Link: https://lore.kernel.org/r/20250411112251.68002-11-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman

nvmem: core: verify cell's raw_len

2025-04-11T12:41:21+00:00

Check that the NVMEM cell's raw_len is a aligned to word_size. Otherwise
Otherwise drivers might face incomplete read while accessing the last
part of the NVMEM cell.

Signed-off-by: Dmitry Baryshkov 
Signed-off-by: Srinivas Kandagatla 
Link: https://lore.kernel.org/r/20250411112251.68002-10-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman

nvmem: core: fix bit offsets of more than one byte

2025-04-11T12:41:21+00:00

If the NVMEM specifies a stride to access data, reading particular cell
might require bit offset that is bigger than one byte. Rework NVMEM core
code to support bit offsets of more than 8 bits.

Signed-off-by: Dmitry Baryshkov 
Signed-off-by: Srinivas Kandagatla 
Link: https://lore.kernel.org/r/20250411112251.68002-9-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman

nvmem: core: improve range check for nvmem_cell_write()

2025-01-10T15:16:48+00:00

When __nvmem_cell_entry_write() is called for an nvmem cell that does
not need bit shifting, it requires that the len parameter exactly
matches the nvmem cell size. However, when the nvmem cell has a nonzero
bit_offset, it was skipping this check.

Accepting values of len larger than the cell size results in
nvmem_cell_prepare_write_buffer() trying to write past the end of a heap
buffer that it allocates. Add a check to avoid that problem and instead
return -EINVAL when len doesn't match the number of bits expected by the
nvmem cell when bit_offset is nonzero.

This check uses cell->nbits in order to allow providing the smaller size
to cells that are shifted into another byte by bit_offset. For example,
a cell with nbits=8 and nonzero bit_offset would have bytes=2 but should
accept a 1-byte write here, although no current callers depend on this.

Fixes: 69aba7948cbe ("nvmem: Add a simple NVMEM framework for consumers")
Cc: stable@vger.kernel.org
Signed-off-by: Jennifer Berringer 
Signed-off-by: Srinivas Kandagatla 
Link: https://lore.kernel.org/r/20241230141901.263976-7-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman

nvmem: core: constify 'struct bin_attribute'

2024-12-30T14:35:59+00:00

The sysfs core now allows instances of 'struct bin_attribute' to be
moved into read-only memory. Make use of that to protect them against
accidental or malicious modifications.

Also adapt the dynamic sysfs cell logic to handle the const attributes.

Signed-off-by: Thomas Weißschuh 
Signed-off-by: Srinivas Kandagatla 
Link: https://lore.kernel.org/r/20241230143035.265518-2-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman

Merge tag 'char-misc-6.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

2024-11-29T19:58:27+00:00

Pull char/misc/IIO/whatever driver subsystem updates from Greg KH:
 "Here is the 'big and hairy' char/misc/iio and other small driver
  subsystem updates for 6.13-rc1.

  Loads of things in here, and even a fun merge conflict!

   - rust misc driver bindings and other rust changes to make misc
     drivers actually possible.

     I think this is the tipping point, expect to see way more rust
     drivers going forward now that these bindings are present. Next
     merge window hopefully we will have pci and platform drivers
     working, which will fully enable almost all driver subsystems to
     start accepting (or at least getting) rust drivers.

     This is the end result of a lot of work from a lot of people,
     congrats to all of them for getting this far, you've proved many of
     us wrong in the best way possible, working code :)

   - IIO driver updates, too many to list individually, that subsystem
     keeps growing and growing...

   - Interconnect driver updates

   - nvmem driver updates

   - pwm driver updates

   - platform_driver::remove() fixups, loads of them

   - counter driver updates

   - misc driver updates (keba?)

   - binder driver updates and fixes

   - loads of other small char/misc/etc driver updates and additions,
     full details in the shortlog.

  All of these have been in linux-next for a while, with no other
  reported issues other than that merge conflict"

* tag 'char-misc-6.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (401 commits)
  mei: vsc: Fix typo "maintstepping" -> "mainstepping"
  firmware: Switch back to struct platform_driver::remove()
  misc: isl29020: Fix the wrong format specifier
  scripts/tags.sh: Don't tag usages of DEFINE_MUTEX
  fpga: Switch back to struct platform_driver::remove()
  mei: vsc: Improve error logging in vsc_identify_silicon()
  mei: vsc: Do not re-enable interrupt from vsc_tp_reset()
  dt-bindings: spmi: qcom,x1e80100-spmi-pmic-arb: Add SAR2130P compatible
  dt-bindings: spmi: spmi-mtk-pmif: Add compatible for MT8188
  spmi: pmic-arb: fix return path in for_each_available_child_of_node()
  iio: Move __private marking before struct element priv in struct iio_dev
  docs: iio: ad7380: add adaq4370-4 and adaq4380-4
  iio: adc: ad7380: add support for adaq4370-4 and adaq4380-4
  iio: adc: ad7380: use local dev variable to shorten long lines
  iio: adc: ad7380: fix oversampling formula
  dt-bindings: iio: adc: ad7380: add adaq4370-4 and adaq4380-4 compatible parts
  bus: mhi: host: pci_generic: Use pcim_iomap_region() to request and map MHI BAR
  bus: mhi: host: Switch trace_mhi_gen_tre fields to native endian
  misc: atmel-ssc: Use of_property_present() for non-boolean properties
  misc: keba: Add hardware dependency
  ...

nvmem: core: Check read_only flag for force_ro in bin_attr_nvmem_write()

2024-11-05T13:01:19+00:00

The bin_attr_nvmem_write() must check the read_only flag and block
writes on read-only devices, now that a nvmem device can be switched
between read-write and read-only mode at runtime using the force_ro
attribute. Add the missing check.

Fixes: 9d7eb234ac7a ("nvmem: core: Implement force_ro sysfs attribute")
Cc: Stable@vger.kernel.org
Signed-off-by: Marek Vasut 
Signed-off-by: Srinivas Kandagatla 
Link: https://lore.kernel.org/r/20241030140253.40445-2-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman

sysfs: treewide: constify attribute callback of bin_is_visible()

2024-11-05T13:00:28+00:00

The is_bin_visible() callbacks should not modify the struct
bin_attribute passed as argument.
Enforce this by marking the argument as const.

As there are not many callback implementers perform this change
throughout the tree at once.

Signed-off-by: Thomas Weißschuh 
Acked-by: Martin K. Petersen 
Acked-by: Jason Gunthorpe 
Acked-by: Ira Weiny 
Acked-by: Krzysztof Wilczyński 
Link: https://lore.kernel.org/r/20241103-sysfs-const-bin_attr-v2-5-71110628844c@weissschuh.net
Signed-off-by: Greg Kroah-Hartman

nvmem: core: calculate bin_attribute size through bin_size()

2024-11-05T13:00:28+00:00

Stop abusing the is_bin_visible() callback to calculate the attribute
size. Instead use the new, dedicated bin_size() one.

Signed-off-by: Thomas Weißschuh 
Acked-by: Krzysztof Wilczyński 
Link: https://lore.kernel.org/r/20241103-sysfs-const-bin_attr-v2-4-71110628844c@weissschuh.net
Signed-off-by: Greg Kroah-Hartman

nvmem: Correct some typos in comments

2024-11-05T04:33:47+00:00

Fixed some confusing typos that were currently identified with codespell,
the details are as follows:

-in the code comments:
drivers/nvmem/brcm_nvram.c:25: underlaying ==> underlying
drivers/nvmem/core.c:1250: alredy ==> already
drivers/nvmem/core.c:1268: alredy ==> already
drivers/nvmem/lpc18xx_otp.c:24: reseverd ==> reserved
drivers/nvmem/microchip-otpc.c:159: devide ==> divide

Signed-off-by: Shen Lichuan 
Acked-by: Vladimir Zapolskiy 
Signed-off-by: Srinivas Kandagatla 
Link: https://lore.kernel.org/r/20241030140315.40562-4-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman