linux-toradex.git/drivers/nvmem, branch v6.15-rc7

nvmem: qfprom: switch to 4-byte aligned reads

2025-04-11T12:41:22+00:00

All platforms since Snapdragon 8 Gen1 (SM8450) require using 4-byte
reads to access QFPROM data. While older platforms were more than happy
with 1-byte reads, change the qfprom driver to use 4-byte reads for all
the platforms. Specify stride and word size of 4 bytes. To retain
compatibility with the existing DT and to simplify porting data from
vendor kernels, use fixup_dt_cell_info in order to bump alignment
requirements.

Signed-off-by: Dmitry Baryshkov 
Signed-off-by: Srinivas Kandagatla 
Link: https://lore.kernel.org/r/20250411112251.68002-12-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman

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: rockchip-otp: add rk3576 variant data

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

The variant works very similar to the rk3588, just with a different
read-offset and size.

Signed-off-by: Heiko Stuebner 
Tested-by: Nicolas Frattaroli 
Signed-off-by: Srinivas Kandagatla 
Link: https://lore.kernel.org/r/20250411112251.68002-5-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman

nvmem: rockchip-otp: Move read-offset into variant-data

2025-04-11T12:41:20+00:00

The RK3588 has an offset into the OTP area where the readable area begins
and automatically adds this to the start address.
Other variants are very much similar to rk3588, just with a different
offset, so move that value into variant-data.

To match the size in bytes, store this value also in bytes and not in
number of blocks.

Signed-off-by: Heiko Stuebner 
Tested-by: Nicolas Frattaroli 
Signed-off-by: Srinivas Kandagatla 
Link: https://lore.kernel.org/r/20250411112251.68002-2-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman

net, treewide: define and use MAC_ADDR_STR_LEN

2025-03-19T18:17:58+00:00

There are a few places in the tree which compute the length of the
string representation of a MAC address as 3 * ETH_ALEN - 1. Define a
constant for this and use it where relevant. No functionality changes
are expected.

Signed-off-by: Uday Shankar 
Reviewed-by: Michal Swiatkowski 
Acked-by: Johannes Berg 
Reviewed-by: Breno Leitao 
Reviewed-by: Simon Horman 
Link: https://patch.msgid.link/20250312-netconsole-v6-1-3437933e79b8@purestorage.com
Signed-off-by: Paolo Abeni

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: qcom-spmi-sdam: Set size in struct nvmem_config

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

Let the nvmem core know what size the SDAM is, most notably this fixes
the size of /sys/bus/nvmem/devices/spmi_sdam*/nvmem being '0' and makes
user space work with that file.

  ~ # hexdump -C -s 64 /sys/bus/nvmem/devices/spmi_sdam2/nvmem
  00000040  02 01 00 00 04 00 00 00  00 00 00 00 00 00 00 00  |................|
  00000050  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
  *
  00000080

Fixes: 40ce9798794f ("nvmem: add QTI SDAM driver")
Cc: stable@vger.kernel.org
Signed-off-by: Luca Weiss 
Reviewed-by: Vladimir Zapolskiy 
Signed-off-by: Srinivas Kandagatla 
Link: https://lore.kernel.org/r/20241230141901.263976-6-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman

nvmem: imx-ocotp-ele: set word length to 1

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

The ELE hardware internally has a word length of 4. However, among other
things we store MAC addresses in the ELE OCOTP. With a length of 6 bytes
these are naturally unaligned to the word length. Therefore we must
support unaligned reads in reg_read() and indeed it works properly when
reg_read() is called via nvmem_reg_read(). Setting the word size to 4
has the only visible effect that doing unaligned reads from userspace
via bin_attr_nvmem_read() do not work because they are rejected by that
function.

Given that we have to abstract from word accesses to byte accesses in
the driver, set the word size to 1. This allows bytewise accesses from
userspace to be able to test what the driver has to support anyway.

Fixes: 22e9e6fcfb50 ("nvmem: imx: support i.MX93 OCOTP")
Signed-off-by: Sascha Hauer 
Cc: stable 
Reviewed-by: Peng Fan 
Signed-off-by: Srinivas Kandagatla 
Link: https://lore.kernel.org/r/20241230141901.263976-5-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman