linux.git/drivers/nvmem/core.c, branch v5.10

nvmem: core: fix possibly memleak when use nvmem_cell_info_to_nvmem_cell()

2020-09-27T12:25:48+00:00

Fix missing 'kfree_const(cell->name)' when call to
nvmem_cell_info_to_nvmem_cell() in several places:

     * after nvmem_cell_info_to_nvmem_cell() failed during
       nvmem_add_cells()

     * during nvmem_device_cell_{read,write} when cell->name is
       kstrdup'ed() without calling kfree_const() at the end, but
       really there is no reason to do that 'dup, because the cell
       instance is allocated on the stack for some short period to be
       read/write without exposing it to the caller.

So the new nvmem_cell_info_to_nvmem_cell_nodup() helper is introduced
which is used to convert cell_info -> cell without name duplication as
a lighweight version of nvmem_cell_info_to_nvmem_cell().

Fixes: e2a5402ec7c6 ("nvmem: Add nvmem_device based consumer apis.")
Reviewed-by: Srinivas Kandagatla 
Acked-by: Srinivas Kandagatla 
Signed-off-by: Vadym Kochan 
Link: https://lore.kernel.org/r/20200923204456.14032-1-vadym.kochan@plvision.eu
Signed-off-by: Greg Kroah-Hartman

nvmem: core: fix missing of_node_put() in of_nvmem_device_get()

2020-09-17T16:48:23+00:00

of_parse_phandle() returns device_node with incremented ref count
which needs to be decremented by of_node_put() when device_node
is not used.

Fixes: e2a5402ec7c6 ("nvmem: Add nvmem_device based consumer apis.")
Signed-off-by: Vadym Kochan 
Signed-off-by: Srinivas Kandagatla 
Link: https://lore.kernel.org/r/20200917134437.16637-5-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman

nvmem: switch to simpler IDA interface

2020-09-17T16:48:23+00:00

We don't need to specify any ranges when allocating IDs so we can switch
to ida_alloc() and ida_free() instead of the ida_simple_ counterparts.

ida_simple_get(ida, 0, 0, gfp) is equivalent to
ida_alloc_range(ida, 0, UINT_MAX, gfp) which is equivalent to
ida_alloc(ida, gfp). Note: IDR will never actually allocate an ID
larger than INT_MAX.

Signed-off-by: Bartosz Golaszewski 
Signed-off-by: Srinivas Kandagatla 
Link: https://lore.kernel.org/r/20200917134437.16637-4-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman

nvmem: core: Use kobj_to_dev() instead of container_of()

2020-09-17T16:48:23+00:00

Use kobj_to_dev() instead of container_of()

Signed-off-by: Tian Tao 
Signed-off-by: Srinivas Kandagatla 
Link: https://lore.kernel.org/r/20200917134437.16637-3-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman

nvmem: core: add support to auto devid

2020-07-29T15:12:08+00:00

For nvmem providers which have multiple instances, it is required
to suffix the provider name with proper id, so that they do not
confict for the same name. Currently the core does not handle
this case properly eventhough core already has logic to generate the id.

This patch add new devid type NVMEM_DEVID_AUTO for providers to be
able to allow core to assign id and append it to provier name.

Reported-by: Shawn Guo 
Signed-off-by: Srinivas Kandagatla 
Tested-by: Shawn Guo 
Link: https://lore.kernel.org/r/20200722100705.7772-8-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman

nvmem: core: Add nvmem_cell_read_u8()

2020-07-29T15:12:08+00:00

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 
Signed-off-by: Srinivas Kandagatla 
Link: https://lore.kernel.org/r/20200722100705.7772-7-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman

nvmem: core: Grammar fixes for help text

2020-07-29T15:12:08+00:00

It's "an unsigned" but "a U".
Similarly, "an entry" but "a binary entry".

While at it, also drop superfluous articles for negative and zero.

Signed-off-by: Andreas Färber 
Signed-off-by: Srinivas Kandagatla 
Link: https://lore.kernel.org/r/20200722100705.7772-6-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman

nvmem: Enforce nvmem stride in the sysfs interface

2020-07-29T15:12:08+00:00

The 'struct nvmem_config' has a stride attribute that specifies the
needed alignment for accesses into the nvmem.  This is used in
nvmem_cell_info_to_nvmem_cell() but not in the sysfs read/write
functions.  If the alignment is important in one place it's important
everywhere, so let's add enforcement.

For now we'll consider it totally invalid to access with the wrong
alignment.  We could relax this in the read case where we could just
read some extra bytes and throw them away.  Relaxing it in the write
case seems harder (and less safe?) since we'd have to read some data
first and then write it back.  To keep it symmetric we'll just
disallow it in both cases.

Reported-by: Ravi Kumar Bokka 
Signed-off-by: Douglas Anderson 
Reviewed-by: Ravi Kumar Bokka 
Tested-by: Ravi Kumar Bokka 
Signed-off-by: Srinivas Kandagatla 
Link: https://lore.kernel.org/r/20200722100705.7772-4-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman

nvmem: ensure sysfs writes handle write-protect pin

2020-05-15T14:20:02+00:00

Commit 2a127da461a9 ("nvmem: add support for the write-protect pin")
added support for handling write-protect pins to the nvmem core, and
Commit 1c89074bf850 ("eeprom: at24: remove the write-protect pin support")
retrofitted the at24 driver to use this support.

These changes broke write() on the nvmem sysfs attribute for eeproms
which utilize a write-protect pin, as the write callback invokes the
nvmem device's reg_write callback directly which no longer handles
changing the state of the write-protect pin.

Change the read and write callbacks for the sysfs attribute to invoke
nvmme_reg_read/nvmem_reg_write helpers which handle this, rather than
calling reg_read/reg_write directly.

Fixes: 2a127da461a9 ("nvmem: add support for the write-protect pin")
Signed-off-by: Michael Auchter 
Signed-off-by: Srinivas Kandagatla 
Link: https://lore.kernel.org/r/20200511145042.31223-3-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman

nvmem: core: cleanup old eeprom compat entry attributes

2020-04-28T13:02:48+00:00

file permission are derived based on various configs for
default nvmem sysfs file, reuse it to create the eeprom
compat file too.

Signed-off-by: Srinivas Kandagatla 
Link: https://lore.kernel.org/r/20200417121306.23121-1-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman