linux-stable.git/drivers/nvmem/core.c, branch v6.6.78

nvmem: core: improve range check for nvmem_cell_write()

2025-02-17T08:40:36+00:00

commit 31507fc2ad36e0071751a710449db19c85d82a7f upstream.

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 
Signed-off-by: Greg Kroah-Hartman

nvmem: core: add nvmem_dev_size() helper

2024-09-18T17:24:04+00:00

[ Upstream commit 33cf42e68efc8ff529a7eee08a4f0ba8c8d0a207 ]

This is required by layouts that need to read whole NVMEM content. It's
especially useful for NVMEM devices without hardcoded layout (like
U-Boot environment data block).

Signed-off-by: Rafał Miłecki 
Reviewed-by: Miquel Raynal 
Link: https://lore.kernel.org/r/20231221173421.13737-2-zajec5@gmail.com
Signed-off-by: Greg Kroah-Hartman 
Stable-dep-of: 8679e8b4a1eb ("nvmem: u-boot-env: error if NVMEM device is too small")
Signed-off-by: Sasha Levin

nvmem: Fix return type of devm_nvmem_device_get() in kerneldoc

2024-09-12T09:11:41+00:00

commit c69f37f6559a8948d70badd2b179db7714dedd62 upstream.

devm_nvmem_device_get() returns an nvmem device, not an nvmem cell.

Fixes: e2a5402ec7c6d044 ("nvmem: Add nvmem_device based consumer apis.")
Cc: stable 
Signed-off-by: Geert Uytterhoeven 
Signed-off-by: Srinivas Kandagatla 
Link: https://lore.kernel.org/r/20240902142510.71096-3-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman

nvmem: core: only change name to fram for current attribute

2024-07-18T11:21:21+00:00

commit 0ba424c934fd43dccf0d597e1ae8851f07cb2edf upstream.

bin_attr_nvmem_eeprom_compat is the template from which all future
compat attributes are created.
Changing it means to change all subsquent compat attributes, too.

Instead only use the "fram" name for the currently registered attribute.

Fixes: fd307a4ad332 ("nvmem: prepare basics for FRAM support")
Cc: stable@vger.kernel.org
Signed-off-by: Thomas Weißschuh 
Signed-off-by: Srinivas Kandagatla 
Link: https://lore.kernel.org/r/20240628113704.13742-4-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman

nvmem: add explicit config option to read old syntax fixed OF cells

2024-05-17T10:01:55+00:00

[ Upstream commit 2cc3b37f5b6df8189d55d0e812d9658ce256dfec ]

Binding for fixed NVMEM cells defined directly as NVMEM device subnodes
has been deprecated. It has been replaced by the "fixed-layout" NVMEM
layout binding.

New syntax is meant to be clearer and should help avoiding imprecise
bindings.

NVMEM subsystem already supports the new binding. It should be a good
idea to limit support for old syntax to existing drivers that actually
support & use it (we can't break backward compatibility!). That way we
additionally encourage new bindings & drivers to ignore deprecated
binding.

It wasn't clear (to me) if rtc and w1 code actually uses old syntax
fixed cells. I enabled them to don't risk any breakage.

Signed-off-by: Rafał Miłecki 
[for meson-{efuse,mx-efuse}.c]
Acked-by: Martin Blumenstingl 
[for mtk-efuse.c, nvmem/core.c, nvmem-provider.h]
Reviewed-by: AngeloGioacchino Del Regno 
[MT8192, MT8195 Chromebooks]
Tested-by: AngeloGioacchino Del Regno 
[for microchip-otpc.c]
Reviewed-by: Claudiu Beznea 
[SAMA7G5-EK]
Tested-by: Claudiu Beznea 
Acked-by: Jernej Skrabec 
Signed-off-by: Srinivas Kandagatla 
Link: https://lore.kernel.org/r/20231020105545.216052-3-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman 
Stable-dep-of: d2d73a6dd173 ("mtd: limit OTP NVMEM cell parse to non-NAND devices")
Signed-off-by: Sasha Levin

nvmem: Do not expect fixed layouts to grab a layout driver

2023-12-13T17:45:31+00:00

commit b7c1e53751cb3990153084f31c41f25fde3b629c upstream.

Two series lived in parallel for some time, which led to this situation:
- The nvmem-layout container is used for dynamic layouts
- We now expect fixed layouts to also use the nvmem-layout container but
this does not require any additional driver, the support is built-in the
nvmem core.

Ensure we don't refuse to probe for wrong reasons.

Fixes: 27f699e578b1 ("nvmem: core: add support for fixed cells *layout*")
Cc: stable@vger.kernel.org
Reported-by: Luca Ceresoli 
Signed-off-by: Miquel Raynal 
Tested-by: Rafał Miłecki 
Tested-by: Luca Ceresoli 
Reviewed-by: Luca Ceresoli 
Link: https://lore.kernel.org/r/20231124193814.360552-1-miquel.raynal@bootlin.com
Signed-off-by: Greg Kroah-Hartman

nvmem: core: Notify when a new layout is registered

2023-08-23T14:34:02+00:00

Tell listeners a new layout was introduced and is now available.

Signed-off-by: Miquel Raynal 
Signed-off-by: Srinivas Kandagatla 
Link: https://lore.kernel.org/r/20230823132744.350618-23-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman

nvmem: core: Do not open-code existing functions

2023-08-23T14:34:02+00:00

Use of_nvmem_layout_get_container() instead of hardcoding it.

Signed-off-by: Miquel Raynal 
Reviewed-by: Michael Walle 
Signed-off-by: Srinivas Kandagatla 
Link: https://lore.kernel.org/r/20230823132744.350618-22-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman

nvmem: core: Create all cells before adding the nvmem device

2023-08-23T14:34:02+00:00

Let's pack all the cells creation in one place, so they are all created
before we add the nvmem device.

Signed-off-by: Miquel Raynal 
Reviewed-by: Michael Walle 
Signed-off-by: Srinivas Kandagatla 
Link: https://lore.kernel.org/r/20230823132744.350618-20-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman

nvmem: Explicitly include correct DT includes

2023-08-23T14:34:01+00:00

The DT of_device.h and of_platform.h date back to the separate
of_platform_bus_type before it as merged into the regular platform bus.
As part of that merge prepping Arm DT support 13 years ago, they
"temporarily" include each other. They also include platform_device.h
and of.h. As a result, there's a pretty much random mix of those include
files used throughout the tree. In order to detangle these headers and
replace the implicit includes with struct declarations, users need to
explicitly include the correct includes.

Signed-off-by: Rob Herring 
Signed-off-by: Srinivas Kandagatla 
Link: https://lore.kernel.org/r/20230823132744.350618-14-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman