nvmem: core: add nvmem_dev_size() helper

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

nvmem: core: add nvmem_dev_size() helper

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 <[email protected]>
Reviewed-by: Miquel Raynal <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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nvmem: Move of_nvmem_layout_get_container() in another header

nvmem-consumer.h is included by consumer devices, extracting data from
NVMEM devices whereas nvmem-provider.h is included by devices pro

nvmem: Move of_nvmem_layout_get_container() in another header

nvmem-consumer.h is included by consumer devices, extracting data from
NVMEM devices whereas nvmem-provider.h is included by devices providing
NVMEM content.

The only users of of_nvmem_layout_get_container() outside of the core
are layout drivers, so better move its prototype to nvmem-provider.h.

While we do so, we also move the kdoc associated with the function to
the header rather than the .c file.

Signed-off-by: Miquel Raynal <[email protected]>
Signed-off-by: Srinivas Kandagatla <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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nvmem: core: Add stub for nvmem_cell_read_u8

Add the stub nvmem_cell_read_u8() function for drivers running with
CONFIG_NVMEM disabled.

Signed-off-by: Komal Bajaj <[email protected]>
Reviewed

nvmem: core: Add stub for nvmem_cell_read_u8

Add the stub nvmem_cell_read_u8() function for drivers running with
CONFIG_NVMEM disabled.

Signed-off-by: Komal Bajaj <[email protected]>
Reviewed-by: Mukesh Ojha <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Bjorn Andersson <[email protected]>

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nvmem: core: Notify when a new layout is registered

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

Signed-off-by: Miquel Raynal <[email protected]>
Signed-off-by: Srinivas

nvmem: core: Notify when a new layout is registered

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

Signed-off-by: Miquel Raynal <[email protected]>
Signed-off-by: Srinivas Kandagatla <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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nvmem: core: Return NULL when no nvmem layout is found

Currently, of_nvmem_layout_get_container() returns NULL on error, or an
error pointer if either CONFIG_NVMEM or CONFIG_OF is turned off. We
sho

nvmem: core: Return NULL when no nvmem layout is found

Currently, of_nvmem_layout_get_container() returns NULL on error, or an
error pointer if either CONFIG_NVMEM or CONFIG_OF is turned off. We
should likely avoid this kind of mix for two reasons: to clarify the
intend and anyway fix the !CONFIG_OF which will likely always if we use
this helper somewhere else. Let's just return NULL when no layout is
found, we don't need an error value here.

Link: https://staticthinking.wordpress.com/2022/08/01/mixing-error-pointers-and-null/
Fixes: 266570f496b9 ("nvmem: core: introduce NVMEM layouts")
Reported-by: kernel test robot <[email protected]>
Reported-by: Dan Carpenter <[email protected]>
Closes: https://lore.kernel.org/r/[email protected]/
Signed-off-by: Miquel Raynal <[email protected]>
Reviewed-by: Michael Walle <[email protected]>
Signed-off-by: Srinivas Kandagatla <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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nvmem: core: introduce NVMEM layouts

NVMEM layouts are used to generate NVMEM cells during runtime. Think of
an EEPROM with a well-defined conent. For now, the content can be
described by a device t

nvmem: core: introduce NVMEM layouts

NVMEM layouts are used to generate NVMEM cells during runtime. Think of
an EEPROM with a well-defined conent. For now, the content can be
described by a device tree or a board file. But this only works if the
offsets and lengths are static and don't change. One could also argue
that putting the layout of the EEPROM in the device tree is the wrong
place. Instead, the device tree should just have a specific compatible
string.

Right now there are two use cases:
(1) The NVMEM cell needs special processing. E.g. if it only specifies
a base MAC address offset and you need to add an offset, or it
needs to parse a MAC from ASCII format or some proprietary format.
(Post processing of cells is added in a later commit).
(2) u-boot environment parsing. The cells don't have a particular
offset but it needs parsing the content to determine the offsets
and length.

Co-developed-by: Miquel Raynal <[email protected]>
Signed-off-by: Miquel Raynal <[email protected]>
Signed-off-by: Michael Walle <[email protected]>
Signed-off-by: Srinivas Kandagatla <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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nvmem: core: move struct nvmem_cell_info to nvmem-provider.h

struct nvmem_cell_info is used to describe a cell. Thus this should
really be in the nvmem-provider's header. There are two (unused) nvme

nvmem: core: move struct nvmem_cell_info to nvmem-provider.h

struct nvmem_cell_info is used to describe a cell. Thus this should
really be in the nvmem-provider's header. There are two (unused) nvmem
access methods which use the nvmem_cell_info to describe the cell to be
accesses. One can argue, that they will create a cell before accessing,
thus they are both a provider and a consumer.

struct nvmem_cell_info will get used more and more by nvmem-providers,
don't force them to also include the consumer header, although they are
not.

Signed-off-by: Michael Walle <[email protected]>
Signed-off-by: Srinivas Kandagatla <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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nvmem: core: support passing DT node in cell info

Some hardware may have NVMEM cells described in Device Tree using
individual nodes. Let drivers pass such nodes to the NVMEM subsystem so
they can b

nvmem: core: support passing DT node in cell info

Some hardware may have NVMEM cells described in Device Tree using
individual nodes. Let drivers pass such nodes to the NVMEM subsystem so
they can be later used by NVMEM consumers.

Signed-off-by: Rafał Miłecki <[email protected]>
Signed-off-by: Srinivas Kandagatla <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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nvmem: core: Add stubs for nvmem_cell_read_variable_le_u32/64 if !CONFIG_NVMEM

When I added nvmem_cell_read_variable_le_u32() and
nvmem_cell_read_variable_le_u64() I forgot to add the "static inline

nvmem: core: Add stubs for nvmem_cell_read_variable_le_u32/64 if !CONFIG_NVMEM

When I added nvmem_cell_read_variable_le_u32() and
nvmem_cell_read_variable_le_u64() I forgot to add the "static inline"
stub functions for when CONFIG_NVMEM wasn't defined. Add them
now. This was causing problems with randconfig builds that compiled
`drivers/soc/qcom/cpr.c`.

Fixes: 6feba6a62c57 ("PM: AVS: qcom-cpr: Use nvmem_cell_read_variable_le_u32()")
Fixes: a28e824fb827 ("nvmem: core: Add functions to make number reading easy")
Reported-by: kernel test robot <[email protected]>
Reviewed-by: Bjorn Andersson <[email protected]>
Signed-off-by: Douglas Anderson <[email protected]>
Signed-off-by: Srinivas Kandagatla <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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nvmem: core: Add functions to make number reading easy

Sometimes the clients of nvmem just want to get a number out of
nvmem. They don't want to think about exactly how many bytes the nvmem
cell too

nvmem: core: Add functions to make number reading easy

Sometimes the clients of nvmem just want to get a number out of
nvmem. They don't want to think about exactly how many bytes the nvmem
cell took up. They just want the number. Let's make it easy.

In general this concept is useful because nvmem space is precious and
usually the fewest bits are allocated that will hold a given value on
a given system. However, even though small numbers might be fine on
one system that doesn't mean that logically the number couldn't be
bigger. Imagine nvmem containing a max frequency for a component. On
one system perhaps that fits in 16 bits. On another system it might
fit in 32 bits. The code reading this number doesn't care--it just
wants the number.

We'll provide two functions: nvmem_cell_read_variable_le_u32() and
nvmem_cell_read_variable_le_u64().

Comparing these to the existing functions like nvmem_cell_read_u32():
* These new functions have no problems if the value was stored in
nvmem in fewer bytes. It's OK to use these function as long as the
value stored will fit in 32-bits (or 64-bits).
* These functions avoid problems that the earlier APIs had with bit
offsets. For instance, you can't use nvmem_cell_read_u32() to read a
value has nbits=32 and bit_offset=4 because the nvmem cell must be
at least 5 bytes big to hold this value. The new API accounts for
this and works fine.
* These functions make it very explicit that they assume that the
number was stored in little endian format. The old functions made
this assumption whenever bit_offset was non-zero (see
nvmem_shift_read_buffer_in_place()) but didn't whenever the
bit_offset was zero.

NOTE: it's assumed that we don't need an 8-bit or 16-bit version of
this function. The 32-bit version of the function can be used to read
8-bit or 16-bit data.

At the moment, I'm only adding the "unsigned" versions of these
functions, but if it ends up being useful someone could add a "signed"
version that did 2's complement sign extension.

At the moment, I'm only adding the "little endian" versions of these
functions. Adding the "big endian" version would require adding "big
endian" support to nvmem_shift_read_buffer_in_place().

Signed-off-by: Douglas Anderson <[email protected]>
Signed-off-by: Srinivas Kandagatla <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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nvmem: core: Add nvmem_cell_read_u8()

Complement the u16, u32 and u64 helpers with a u8 variant to ease
accessing byte-sized values.

This helper will be useful for Realtek Digital Home Center platf

nvmem: core: Add nvmem_cell_read_u8()

Complement the u16, u32 and u64 helpers with a u8 variant to ease
accessing byte-sized values.

This helper will be useful for Realtek Digital Home Center platforms,
which store some byte and sub-byte sized values in non-volatile memory.

Signed-off-by: Andreas Färber <[email protected]>
Signed-off-by: Srinivas Kandagatla <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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nvmem: core: add nvmem_cell_read_u64

Add nvmem_cell_read_u64() helper to ease read of an u64 value on consumer
side. This helper is useful on some sunxi platform that has 64 bits data
cells stored i

nvmem: core: add nvmem_cell_read_u64

Add nvmem_cell_read_u64() helper to ease read of an u64 value on consumer
side. This helper is useful on some sunxi platform that has 64 bits data
cells stored in no volatile memory.

Signed-off-by: Yangtao Li <[email protected]>
Signed-off-by: Srinivas Kandagatla <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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nvmem: core: fix nvmem_cell_write inline function

nvmem_cell_write's buf argument uses different types based on
the configuration of CONFIG_NVMEM. The function prototype for
enabled NVMEM uses 'void

nvmem: core: fix nvmem_cell_write inline function

nvmem_cell_write's buf argument uses different types based on
the configuration of CONFIG_NVMEM. The function prototype for
enabled NVMEM uses 'void *' type, but the static dummy function
for disabled NVMEM uses 'const char *' instead. Fix the different
behaviour by always expecting a 'void *' typed buf argument.

Fixes: 7a78a7f7695b ("power: reset: nvmem-reboot-mode: use NVMEM as reboot mode write interface")
Reported-by: kbuild test robot <[email protected]>
Cc: Han Nandor <[email protected]>
Cc: Srinivas Kandagatla <[email protected]>
Cc: [email protected]
Signed-off-by: Sebastian Reichel <[email protected]>
Reviewed-By: Han Nandor <[email protected]>
Signed-off-by: Srinivas Kandagatla <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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nvmem: core: add nvmem_device_find

nvmem_device_find provides a way to search for nvmem devices with
the help of a match function simlair to bus_find_device.

Reviewed-by: Srinivas Kandagatla <srini

nvmem: core: add nvmem_device_find

nvmem_device_find provides a way to search for nvmem devices with
the help of a match function simlair to bus_find_device.

Reviewed-by: Srinivas Kandagatla <[email protected]>
Acked-by: Srinivas Kandagatla <[email protected]>
Signed-off-by: Thomas Bogendoerfer <[email protected]>
Signed-off-by: Paul Burton <[email protected]>
Cc: Jonathan Corbet <[email protected]>
Cc: Ralf Baechle <[email protected]>
Cc: James Hogan <[email protected]>
Cc: Lee Jones <[email protected]>
Cc: David S. Miller <[email protected]>
Cc: Alessandro Zummo <[email protected]>
Cc: Alexandre Belloni <[email protected]>
Cc: Greg Kroah-Hartman <[email protected]>
Cc: Jiri Slaby <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]

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nvmem: core: add nvmem_cell_read_u16

Add nvmem_cell_read_u16() helper to ease read of an u16 value on consumer
side. This is inspired by nvmem_cell_read_u32() function.
This helper is useful on stm3

nvmem: core: add nvmem_cell_read_u16

Add nvmem_cell_read_u16() helper to ease read of an u16 value on consumer
side. This is inspired by nvmem_cell_read_u32() function.
This helper is useful on stm32 that has 16 bits data cells stored in non
volatile memory.

Signed-off-by: Fabrice Gasnier <[email protected]>
Signed-off-by: Srinivas Kandagatla <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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nvmem: use EOPNOTSUPP instead of ENOSYS

Checkpatch emits warnings when using ENOSYS. Some of the frameworks
started using EOPNOTSUPP as return values for API functions when given
subsystem is disabl

nvmem: use EOPNOTSUPP instead of ENOSYS

Checkpatch emits warnings when using ENOSYS. Some of the frameworks
started using EOPNOTSUPP as return values for API functions when given
subsystem is disabled in Kconfig.

Signed-off-by: Bartosz Golaszewski <[email protected]>
Signed-off-by: Srinivas Kandagatla <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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nvmem: make the naming of arguments in nvmem_cell_get() consistent

The argument representing the cell name in the nvmem_cell_get() family
of functions is not consistend between function prototypes a

nvmem: make the naming of arguments in nvmem_cell_get() consistent

The argument representing the cell name in the nvmem_cell_get() family
of functions is not consistend between function prototypes and
definitions. Name it 'id' in all those routines. This is in line with
other frameworks and can represent both the DT cell name from the
nvmem-cell-names property as well as the con_id field from cell
lookup entries.

Signed-off-by: Bartosz Golaszewski <[email protected]>
Signed-off-by: Srinivas Kandagatla <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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nvmem: use SPDX license identifiers

Use SPDX license identiefiers to core nvmem files and remove GPL 2.0
license boilerplate.

Signed-off-by: Bartosz Golaszewski <[email protected]>
Signed-o

nvmem: use SPDX license identifiers

Use SPDX license identiefiers to core nvmem files and remove GPL 2.0
license boilerplate.

Signed-off-by: Bartosz Golaszewski <[email protected]>
Signed-off-by: Srinivas Kandagatla <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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nvmem: add a notifier chain

Add a blocking notifier chain with four events (add and remove for
both devices and cells) so that users can get notified about the
addition of nvmem resources they're wa

nvmem: add a notifier chain

Add a blocking notifier chain with four events (add and remove for
both devices and cells) so that users can get notified about the
addition of nvmem resources they're waiting for.

We'll use this instead of the at24 setup callback in the mityomapl138
board file.

Signed-off-by: Bartosz Golaszewski <[email protected]>
Signed-off-by: Srinivas Kandagatla <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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nvmem: add support for cell lookups from machine code

Add a way for machine code users to associate devices with nvmem cells.

This restores the support for non-DT systems but following a different

nvmem: add support for cell lookups from machine code

Add a way for machine code users to associate devices with nvmem cells.

This restores the support for non-DT systems but following a different
approach. Cells must now be associated with devices using provided
routines and data structures before they can be retrieved using
nvmem_cell_get().

It's still possible to define cells statically in nvmem_config but
cells created this way still need to be associated with consumers using
lookup entries.

Note that nvmem_find() must be moved higher in the source file as we
want to call it from __nvmem_device_get() for devices that don't have
a device node.

The signature of __nvmem_device_get() is also changed as it's no longer
used to retrieve cells.

Signed-off-by: Bartosz Golaszewski <[email protected]>
Signed-off-by: Srinivas Kandagatla <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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nvmem: provide nvmem_dev_name()

Kernel users don't have any means of checking the names of nvmem
devices. Add a routine that returns the name of the nvmem provider.

This will be useful for future n

nvmem: provide nvmem_dev_name()

Kernel users don't have any means of checking the names of nvmem
devices. Add a routine that returns the name of the nvmem provider.

This will be useful for future nvmem notifier subscribers - otherwise
they can't check what device is being added/removed.

Signed-off-by: Bartosz Golaszewski <[email protected]>
Signed-off-by: Srinivas Kandagatla <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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nvmem: include linux/err.h from header

missing err.h header file can cause simillar errors like below
in some configurations.
"error: implicit declaration of function 'ERR_PTR'
[-Werror=implicit-fun

nvmem: include linux/err.h from header

missing err.h header file can cause simillar errors like below
in some configurations.
"error: implicit declaration of function 'ERR_PTR'
[-Werror=implicit-function-declaration]"

This adds the missing include to ensure we can always include
the header.

Signed-off-by: Srinivas Kandagatla <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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nvmem: core: Add nvmem_cell_read_u32

This function does a quick and easy read of an u32 value without any
kind of resource management code on the consumer side.

Signed-off-by: Leonard Crestez <leon

nvmem: core: Add nvmem_cell_read_u32

This function does a quick and easy read of an u32 value without any
kind of resource management code on the consumer side.

Signed-off-by: Leonard Crestez <[email protected]>
Reviewed-by: Shawn Guo <[email protected]>
Signed-off-by: Srinivas Kandagatla <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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nvmem: Declare nvmem_cell_read() consistently

nvmem_cell_read() is declared as void * if CONFIG_NVMEM is enabled, and
as char * otherwise. This can result in a build warning if CONFIG_NVMEM
is not e

nvmem: Declare nvmem_cell_read() consistently

nvmem_cell_read() is declared as void * if CONFIG_NVMEM is enabled, and
as char * otherwise. This can result in a build warning if CONFIG_NVMEM
is not enabled and a caller asigns the result to a type other than char *
without using a typecast. Use a consistent declaration to avoid the
problem.

Fixes: e2a5402ec7c6 ("nvmem: Add nvmem_device based consumer apis.")
Cc: Srinivas Kandagatla <[email protected]>
Signed-off-by: Guenter Roeck <[email protected]>
Signed-off-by: Srinivas Kandagatla <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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nvmem: Add nvmem_device based consumer apis.

This patch adds read/write apis which are based on nvmem_device. It is
common that the drivers like omap cape manager or qcom cpr driver to
access bytes

nvmem: Add nvmem_device based consumer apis.

This patch adds read/write apis which are based on nvmem_device. It is
common that the drivers like omap cape manager or qcom cpr driver to
access bytes directly at particular offset in the eeprom and not from
nvmem cell info in DT. These driver would need to get access to the nvmem
directly, which is what these new APIS provide.

These wrapper apis would help such users to avoid code duplication in
there drivers and also avoid them reading a big eeprom blob and parsing
it internally in there driver.

Signed-off-by: Srinivas Kandagatla <[email protected]>
Tested-by: Stefan Wahren <[email protected]>
Tested-by: Philipp Zabel <[email protected]>
Tested-by: Rajendra Nayak <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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