200 Commits
Author SHA1 Message Date
Linus Torvalds bf4afc53b7 Convert 'alloc_obj' family to use the new default GFP_KERNEL argument
This was done entirely with mindless brute force, using

    git grep -l '\<k[vmz]*alloc_objs*(.*, GFP_KERNEL)' |
        xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/'

to convert the new alloc_obj() users that had a simple GFP_KERNEL
argument to just drop that argument.

Note that due to the extreme simplicity of the scripting, any slightly
more complex cases spread over multiple lines would not be triggered:
they definitely exist, but this covers the vast bulk of the cases, and
the resulting diff is also then easier to check automatically.

For the same reason the 'flex' versions will be done as a separate
conversion.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2026-02-21 17:09:51 -08:00
Kees Cook 69050f8d6d treewide: Replace kmalloc with kmalloc_obj for non-scalar types
This is the result of running the Coccinelle script from
scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to
avoid scalar types (which need careful case-by-case checking), and
instead replace kmalloc-family calls that allocate struct or union
object instances:

Single allocations:	kmalloc(sizeof(TYPE), ...)
are replaced with:	kmalloc_obj(TYPE, ...)

Array allocations:	kmalloc_array(COUNT, sizeof(TYPE), ...)
are replaced with:	kmalloc_objs(TYPE, COUNT, ...)

Flex array allocations:	kmalloc(struct_size(PTR, FAM, COUNT), ...)
are replaced with:	kmalloc_flex(*PTR, FAM, COUNT, ...)

(where TYPE may also be *VAR)

The resulting allocations no longer return "void *", instead returning
"TYPE *".

Signed-off-by: Kees Cook <kees@kernel.org>
2026-02-21 01:02:28 -08:00
Krzysztof KozlowskiandGreg Kroah-Hartman e75c79f249 nvmem: Simplify with scoped for each OF child loop
Use scoped for-each loop when iterating over device nodes to make code a
bit simpler.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>
Signed-off-by: Srinivas Kandagatla <srini@kernel.org>
Link: https://patch.msgid.link/20260116170846.733558-3-srini@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-01-26 16:40:33 +01:00
Krzysztof KozlowskiandGreg Kroah-Hartman f397bc0781 nvmem: Drop OF node reference on nvmem_add_one_cell() failure
If nvmem_add_one_cell() failed, the ownership of "child" (or "info.np"),
thus its OF reference, is not passed further and function should clean
up by putting the reference it got via earlier of_node_get().  Note that
this is independent of references obtained via for_each_child_of_node()
loop.

Fixes: 50014d6596 ("nvmem: core: use nvmem_add_one_cell() in nvmem_add_cells_from_of()")
Cc: stable@vger.kernel.org
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>
Signed-off-by: Srinivas Kandagatla <srini@kernel.org>
Link: https://patch.msgid.link/20260116170846.733558-2-srini@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-01-26 16:40:33 +01:00
Linus Torvalds 22c5696e3f Merge tag 'driver-core-6.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core
Pull driver core updates from Danilo Krummrich:
 "debugfs:
   - Remove unneeded debugfs_file_{get,put}() instances
   - Remove last remnants of debugfs_real_fops()
   - Allow storing non-const void * in struct debugfs_inode_info::aux

  sysfs:
   - Switch back to attribute_group::bin_attrs (treewide)
   - Switch back to bin_attribute::read()/write() (treewide)
   - Constify internal references to 'struct bin_attribute'

  Support cache-ids for device-tree systems:
   - Add arch hook arch_compact_of_hwid()
   - Use arch_compact_of_hwid() to compact MPIDR values on arm64

  Rust:
   - Device:
       - Introduce CoreInternal device context (for bus internal methods)
       - Provide generic drvdata accessors for bus devices
       - Provide Driver::unbind() callbacks
       - Use the infrastructure above for auxiliary, PCI and platform
       - Implement Device::as_bound()
       - Rename Device::as_ref() to Device::from_raw() (treewide)
       - Implement fwnode and device property abstractions
       - Implement example usage in the Rust platform sample driver
   - Devres:
       - Remove the inner reference count (Arc) and use pin-init instead
       - Replace Devres::new_foreign_owned() with devres::register()
       - Require T to be Send in Devres<T>
       - Initialize the data kept inside a Devres last
       - Provide an accessor for the Devres associated Device
   - Device ID:
       - Add support for ACPI device IDs and driver match tables
       - Split up generic device ID infrastructure
       - Use generic device ID infrastructure in net::phy
   - DMA:
       - Implement the dma::Device trait
       - Add DMA mask accessors to dma::Device
       - Implement dma::Device for PCI and platform devices
       - Use DMA masks from the DMA sample module
   - I/O:
       - Implement abstraction for resource regions (struct resource)
       - Implement resource-based ioremap() abstractions
       - Provide platform device accessors for I/O (remap) requests
   - Misc:
       - Support fallible PinInit types in Revocable
       - Implement Wrapper<T> for Opaque<T>
       - Merge pin-init blanket dependencies (for Devres)

  Misc:
   - Fix OF node leak in auxiliary_device_create()
   - Use util macros in device property iterators
   - Improve kobject sample code
   - Add device_link_test() for testing device link flags
   - Fix typo in Documentation/ABI/testing/sysfs-kernel-address_bits
   - Hint to prefer container_of_const() over container_of()"

* tag 'driver-core-6.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core: (84 commits)
  rust: io: fix broken intra-doc links to `platform::Device`
  rust: io: fix broken intra-doc link to missing `flags` module
  rust: io: mem: enable IoRequest doc-tests
  rust: platform: add resource accessors
  rust: io: mem: add a generic iomem abstraction
  rust: io: add resource abstraction
  rust: samples: dma: set DMA mask
  rust: platform: implement the `dma::Device` trait
  rust: pci: implement the `dma::Device` trait
  rust: dma: add DMA addressing capabilities
  rust: dma: implement `dma::Device` trait
  rust: net::phy Change module_phy_driver macro to use module_device_table macro
  rust: net::phy represent DeviceId as transparent wrapper over mdio_device_id
  rust: device_id: split out index support into a separate trait
  device: rust: rename Device::as_ref() to Device::from_raw()
  arm64: cacheinfo: Provide helper to compress MPIDR value into u32
  cacheinfo: Add arch hook to compress CPU h/w id into 32 bits for cache-id
  cacheinfo: Set cache 'id' based on DT data
  container_of: Document container_of() is not to be used in new code
  driver core: auxiliary bus: fix OF node leak
  ...
2025-07-29 12:15:39 -07:00
Greg Kroah-Hartman fc03681216 nvmem: make nvmem_bus_type constant
Now that the driver core can properly handle constant struct bus_type,
move the nvmem_bus_type variable to be a constant structure as well,
placing it into read-only memory which can not be modified at runtime.

Cc: Srinivas Kandagatla <srini@kernel.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Srinivas Kandagatla <srini@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20250712181905.6738-6-srini@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-07-16 14:30:05 +02:00
Alok TiwariandGreg Kroah-Hartman 0e0de622c2 nvmem: core: Fix typos in comments and MODULE_AUTHOR strings
This patch fixes minor typo issues for nvmem-core.c:
 Corrects "form" to "from" in multiple function descriptions.
 Fixes missing closing angle brackets in MODULE_AUTHOR entries.

These changes improve readability and formatting consistency.

Signed-off-by: Alok Tiwari <alok.a.tiwari@oracle.com>
Signed-off-by: Srinivas Kandagatla <srini@kernel.org>
Link: https://lore.kernel.org/r/20250712181905.6738-4-srini@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-07-16 14:30:04 +02:00
Thomas WeißschuhandGreg Kroah-Hartman fb506e31b3 sysfs: treewide: switch back to attribute_group::bin_attrs
The normal bin_attrs field can now handle const pointers.
This makes the _new variant unnecessary.
Switch all users back.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Link: https://lore.kernel.org/r/20250530-sysfs-const-bin_attr-final-v3-4-724bfcf05b99@weissschuh.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-06-17 10:44:15 +02:00
Thomas WeißschuhandGreg Kroah-Hartman 2fbe82037a sysfs: treewide: switch back to bin_attribute::read()/write()
The bin_attribute argument of bin_attribute::read() is now const.
This makes the _new() callbacks unnecessary. Switch all users back.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Link: https://lore.kernel.org/r/20250530-sysfs-const-bin_attr-final-v3-3-724bfcf05b99@weissschuh.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-06-17 10:44:13 +02:00
Geert UytterhoevenandGreg Kroah-Hartman 01465f296a nvmem: Remove unused nvmem cell table support
Board files are deprecated by DT, and the last user of
nvmem_add_cell_table() was removed by commit 2af4fcc0d3 ("ARM:
davinci: remove unused board support") in v6.3.  Hence remove all
support for nvmem cell tables, and update the documentation.

Device drivers can still register a single cell using
nvmem_add_one_cell() (which was not documented before).

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Srinivas Kandagatla <srini@kernel.org>
Link: https://lore.kernel.org/r/20250509122452.11827-2-srini@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-05-21 14:28:27 +02:00
Dmitry BaryshkovandGreg Kroah-Hartman 6786484223 nvmem: core: update raw_len if the bit reading is required
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 <dmitry.baryshkov@linaro.org>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20250411112251.68002-11-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-04-11 14:41:21 +02:00
Dmitry BaryshkovandGreg Kroah-Hartman 13bcd440f2 nvmem: core: verify cell's raw_len
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 <dmitry.baryshkov@linaro.org>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20250411112251.68002-10-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-04-11 14:41:21 +02:00
Dmitry BaryshkovandGreg Kroah-Hartman 7a06ef7510 nvmem: core: fix bit offsets of more than one byte
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 <dmitry.baryshkov@linaro.org>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20250411112251.68002-9-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-04-11 14:41:21 +02:00
Jennifer BerringerandGreg Kroah-Hartman 31507fc2ad nvmem: core: improve range check for nvmem_cell_write()
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: 69aba7948c ("nvmem: Add a simple NVMEM framework for consumers")
Cc: stable@vger.kernel.org
Signed-off-by: Jennifer Berringer <jberring@redhat.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20241230141901.263976-7-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-01-10 16:16:48 +01:00
Thomas WeißschuhandGreg Kroah-Hartman 78dc14daf4 nvmem: core: constify 'struct bin_attribute'
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 <linux@weissschuh.net>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20241230143035.265518-2-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-12-30 15:35:59 +01:00
Linus Torvalds 2eff01ee28 Merge tag 'char-misc-6.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc
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
  ...
2024-11-29 11:58:27 -08:00
Marek VasutandGreg Kroah-Hartman da9596955c nvmem: core: Check read_only flag for force_ro in bin_attr_nvmem_write()
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: 9d7eb234ac ("nvmem: core: Implement force_ro sysfs attribute")
Cc: Stable@vger.kernel.org
Signed-off-by: Marek Vasut <marex@denx.de>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20241030140253.40445-2-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-05 14:01:19 +01:00
Thomas WeißschuhandGreg Kroah-Hartman b626816fdd sysfs: treewide: constify attribute callback of bin_is_visible()
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 <linux@weissschuh.net>
Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: Jason Gunthorpe <jgg@nvidia.com>
Acked-by: Ira Weiny <ira.weiny@intel.com>
Acked-by: Krzysztof Wilczyński <kw@linux.com>
Link: https://lore.kernel.org/r/20241103-sysfs-const-bin_attr-v2-5-71110628844c@weissschuh.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-05 14:00:28 +01:00
Thomas WeißschuhandGreg Kroah-Hartman 00ab6e97de nvmem: core: calculate bin_attribute size through bin_size()
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 <linux@weissschuh.net>
Acked-by: Krzysztof Wilczyński <kw@linux.com>
Link: https://lore.kernel.org/r/20241103-sysfs-const-bin_attr-v2-4-71110628844c@weissschuh.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-05 14:00:28 +01:00
Shen LichuanandGreg Kroah-Hartman b3d75e9ba0 nvmem: Correct some typos in comments
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 <shenlichuan@vivo.com>
Acked-by: Vladimir Zapolskiy <vz@mleia.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20241030140315.40562-4-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-05 05:33:47 +01:00
Geert UytterhoevenandGreg Kroah-Hartman c69f37f655 nvmem: Fix return type of devm_nvmem_device_get() in kerneldoc
devm_nvmem_device_get() returns an nvmem device, not an nvmem cell.

Fixes: e2a5402ec7 ("nvmem: Add nvmem_device based consumer apis.")
Cc: stable <stable@kernel.org>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20240902142510.71096-3-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-09-03 12:20:41 +02:00
Linus Torvalds acc5965b9f Merge tag 'char-misc-6.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc
Pull char / misc and other driver updates from Greg KH:
 "Here is the "big" set of char/misc and other driver subsystem changes
  for 6.11-rc1. Nothing major in here, just loads of new drivers and
  updates. Included in here are:

   - IIO api updates and new drivers added

   - wait_interruptable_timeout() api cleanups for some drivers

   - MODULE_DESCRIPTION() additions for loads of drivers

   - parport out-of-bounds fix

   - interconnect driver updates and additions

   - mhi driver updates and additions

   - w1 driver fixes

   - binder speedups and fixes

   - eeprom driver updates

   - coresight driver updates

   - counter driver update

   - new misc driver additions

   - other minor api updates

  All of these, EXCEPT for the final Kconfig build fix for 32bit
  systems, have been in linux-next for a while with no reported issues.
  The Kconfig fixup went in 29 hours ago, so might have missed the
  latest linux-next, but was acked by everyone involved"

* tag 'char-misc-6.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (330 commits)
  misc: Kconfig: exclude mrvl-cn10k-dpi compilation for 32-bit systems
  misc: delete Makefile.rej
  binder: fix hang of unregistered readers
  misc: Kconfig: add a new dependency for MARVELL_CN10K_DPI
  virtio: add missing MODULE_DESCRIPTION() macro
  agp: uninorth: add missing MODULE_DESCRIPTION() macro
  spmi: add missing MODULE_DESCRIPTION() macros
  dev/parport: fix the array out-of-bounds risk
  samples: configfs: add missing MODULE_DESCRIPTION() macro
  misc: mrvl-cn10k-dpi: add Octeon CN10K DPI administrative driver
  misc: keba: Fix missing AUXILIARY_BUS dependency
  slimbus: Fix struct and documentation alignment in stream.c
  MAINTAINERS: CC dri-devel list on Qualcomm FastRPC patches
  misc: fastrpc: use coherent pool for untranslated Compute Banks
  misc: fastrpc: support complete DMA pool access to the DSP
  misc: fastrpc: add missing MODULE_DESCRIPTION() macro
  misc: fastrpc: Add missing dev_err newlines
  misc: fastrpc: Use memdup_user()
  nvmem: core: Implement force_ro sysfs attribute
  nvmem: Use sysfs_emit() for type attribute
  ...
2024-07-19 15:55:08 -07:00
Marek VasutandGreg Kroah-Hartman 9d7eb234ac nvmem: core: Implement force_ro sysfs attribute
Implement "force_ro" sysfs attribute to allow users to set read-write
devices as read-only and back to read-write from userspace. The choice
of the name is based on MMC core 'force_ro' attribute.

This solves a situation where an AT24 I2C EEPROM with GPIO based nWP
signal may have to be occasionally updated. Such I2C EEPROM device is
usually set as read-only during most of the regular system operation,
but in case it has to be updated in a controlled manner, it could be
unlocked using this new "force_ro" sysfs attribute and then re-locked
again.

The "read-only" DT property and config->read_only configuration is
respected and is used to set default state of the device, read-only
or read-write, for devices which do implement .reg_write function.
For devices which do not implement .reg_write function, the device
is unconditionally read-only and the "force_ro" attribute is not
visible.

Signed-off-by: Marek Vasut <marex@denx.de>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20240705074852.423202-16-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-07-05 09:55:05 +02:00
Marek VasutandGreg Kroah-Hartman 08c367e45b nvmem: Use sysfs_emit() for type attribute
Use sysfs_emit() instead of sprintf() to follow best practice per
Documentation/filesystems/sysfs.rst
"
show() should only use sysfs_emit()...
"

Signed-off-by: Marek Vasut <marex@denx.de>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20240705074852.423202-15-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-07-05 09:55:05 +02:00
Thomas WeißschuhandGreg Kroah-Hartman 588773802c nvmem: core: drop unnecessary range checks in sysfs callbacks
The same checks have already been done in sysfs_kf_bin_write() and
sysfs_kf_bin_read() just before the callbacks are invoked.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20240705074852.423202-12-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-07-05 09:55:05 +02:00