linux-toradex.git/drivers/nvmem, branch v6.14-rc3

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

nvmem: imx-ocotp-ele: fix MAC address byte order

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

According to the i.MX93 Fusemap the two MAC addresses are stored in
words 315 to 317 like this:

315	MAC1_ADDR_31_0[31:0]
316	MAC1_ADDR_47_32[47:32]
	MAC2_ADDR_15_0[15:0]
317	MAC2_ADDR_47_16[31:0]

This means the MAC addresses are stored in reverse byte order. We have
to swap the bytes before passing them to the upper layers. The storage
format is consistent to the one used on i.MX6 using imx-ocotp driver
which does the same byte swapping as introduced here.

With this patch the MAC address on my i.MX93 TQ board correctly reads as
00:d0:93:6b:27:b8 instead of b8:27:6b:93:d0:00.

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/20241230141901.263976-4-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman

nvmem: imx-ocotp-ele: fix reading from non zero offset

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

In imx_ocotp_reg_read() the offset comes in as bytes and not as words.
This means we have to divide offset by 4 to get to the correct word
offset.

Also the incoming offset might not be word aligned. In order to read
from the OCOTP the driver aligns down the previous word boundary and
reads from there. This means we have to skip this alignment offset from
the temporary buffer when copying the data to the output buffer.

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/20241230141901.263976-3-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman

nvmem: imx-ocotp-ele: simplify read beyond device check

2025-01-10T15:16:47+00:00

Do the read beyond device check on function entry in bytes instead of
32bit words which is easier to follow.

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/20241230141901.263976-2-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman

nvmem: rmem: add CRC validation for Mobileye EyeQ5 NVMEM

2024-12-30T14:36:00+00:00

Mobileye EyeQ5 has a non-volatile memory region which
gets used to store MAC addresses. Its format includes
a prefix 12-byte header and a suffix 4-byte CRC.

Add an optional ->checksum() callback inside match data;
it runs CRC32 onto the content.

Signed-off-by: Théo Lebrun 
Signed-off-by: Srinivas Kandagatla 
Link: https://lore.kernel.org/r/20241230143035.265518-7-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman

nvmem: rmem: remove unused struct rmem::size field

2024-12-30T14:36:00+00:00

The private structure used by the rmem driver contains
a `size` field that is unused. Remove it.

Signed-off-by: Théo Lebrun 
Signed-off-by: Srinivas Kandagatla 
Link: https://lore.kernel.org/r/20241230143035.265518-6-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman

nvmem: rmem: make ->reg_read() straight forward code

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

memory_read_from_buffer() is a weird choice; it:
 - is made for iteration with ppos a pointer.
 - does futile error checking in our case.
 - does NOT ensure we read exactly N bytes.

Replace it by:
1. A check that (offset + bytes) lands inside the region and,
2. a plain memcpy().

Signed-off-by: Théo Lebrun 
Signed-off-by: Srinivas Kandagatla 
Link: https://lore.kernel.org/r/20241230143035.265518-5-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