kernel/linux.git/drivers/nvmem/core.c, branch v6.12.80

nvmem: Drop OF node reference on nvmem_add_one_cell() failure

2026-03-04T12:21:49+00:00

[ Upstream commit f397bc0781553d01b4cdba506c09334a31cb0ec5 ] 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: 50014d659617 ("nvmem: core: use nvmem_add_one_cell() in nvmem_add_cells_from_of()") Cc: stable@vger.kernel.org Signed-off-by: Krzysztof Kozlowski Signed-off-by: Srinivas Kandagatla Link: https://patch.msgid.link/20260116170846.733558-2-srini@kernel.org Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin

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

2025-05-29T09:01:57+00:00

[ Upstream commit 6786484223d5705bf7f919c1e5055d478ebeec32 ] 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 Signed-off-by: Sasha Levin

nvmem: core: verify cell's raw_len

2025-05-29T09:01:57+00:00

[ Upstream commit 13bcd440f2ff38cd7e42a179c223d4b833158b33 ] 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 Signed-off-by: Sasha Levin

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

2025-05-29T09:01:57+00:00

[ Upstream commit 7a06ef75107799675ea6e4d73b9df37e18e352a8 ] 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 Signed-off-by: Sasha Levin

nvmem: core: improve range check for nvmem_cell_write()

2025-02-17T09:05:37+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: Check read_only flag for force_ro in bin_attr_nvmem_write()

2024-12-09T09:41:03+00:00

commit da9596955c05966768364ab1cad2f43fcddc6f06 upstream. 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

nvmem: Fix return type of devm_nvmem_device_get() in kerneldoc

2024-09-03T10:20:41+00:00

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

Merge tag 'char-misc-6.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

2024-07-19T22:55:08+00:00

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 ...

nvmem: core: Implement force_ro sysfs attribute

2024-07-05T07:55:05+00:00

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 Signed-off-by: Srinivas Kandagatla Link: https://lore.kernel.org/r/20240705074852.423202-16-srinivas.kandagatla@linaro.org Signed-off-by: Greg Kroah-Hartman

nvmem: Use sysfs_emit() for type attribute

2024-07-05T07:55:05+00:00

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 Signed-off-by: Srinivas Kandagatla Link: https://lore.kernel.org/r/20240705074852.423202-15-srinivas.kandagatla@linaro.org Signed-off-by: Greg Kroah-Hartman