Hi Rafał,

I love your patch! Yet something to improve:

[auto build test ERROR on next-20230111]
[cannot apply to robh/for-next shawnguo/for-next mtd/mtd/next mtd/mtd/fixes linus/master v6.2-rc3 v6.2-rc2 v6.2-rc1 v6.2-rc3]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Rafa-Mi-ecki/nvmem-core-allow-read_post_process-callbacks-to-adjust-buffer/20230111-153322
patch link:    https://lore.kernel.org/r/20230111073102.8147-2-zajec5%40gmail.com
patch subject: [PATCH V2 2/6] nvmem: core: allow .read_post_process() callbacks to adjust buffer
config: arm64-randconfig-r002-20230110
compiler: clang version 16.0.0 (https://github.com/llvm/llvm-project 8d9828ef5aa9688500657d36cd2aefbe12bbd162)
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # install arm64 cross compiling tool for clang build
        # apt-get install binutils-aarch64-linux-gnu
        # https://github.com/intel-lab-lkp/linux/commit/8feca4b80acb7b0d1d460fef6091ff48b54e60c6
        git remote add linux-review https://github.com/intel-lab-lkp/linux
        git fetch --no-tags linux-review Rafa-Mi-ecki/nvmem-core-allow-read_post_process-callbacks-to-adjust-buffer/20230111-153322
        git checkout 8feca4b80acb7b0d1d460fef6091ff48b54e60c6
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=arm64 olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=arm64 SHELL=/bin/bash drivers/nvmem/

If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <lkp@intel.com>

All error/warnings (new ones prefixed by >>):

>> drivers/nvmem/core.c:1916:45: error: incompatible pointer types passing 'int *' to parameter of type 'size_t *' (aka 'unsigned long *') [-Werror,-Wincompatible-pointer-types]
           rc = __nvmem_cell_read(nvmem, &cell, &buf, &cell.bytes, NULL, 0);
                                                      ^~~~~~~~~~~
   drivers/nvmem/core.c:1541:29: note: passing argument to parameter 'len' here
                                void **buf, size_t *len, const char *id, int index)
                                                    ^
>> drivers/nvmem/core.c:1920:9: warning: variable 'len' is uninitialized when used here [-Wuninitialized]
           return len;
                  ^~~
   drivers/nvmem/core.c:1903:13: note: initialize the variable 'len' to silence this warning
           ssize_t len;
                      ^
                       = 0
   1 warning and 1 error generated.


vim +1916 drivers/nvmem/core.c

  1887	
  1888	/**
  1889	 * nvmem_device_cell_read() - Read a given nvmem device and cell
  1890	 *
  1891	 * @nvmem: nvmem device to read from.
  1892	 * @info: nvmem cell info to be read.
  1893	 * @buf: buffer pointer which will be populated on successful read.
  1894	 *
  1895	 * Return: length of successful bytes read on success and negative
  1896	 * error code on error.
  1897	 */
  1898	ssize_t nvmem_device_cell_read(struct nvmem_device *nvmem,
  1899				   struct nvmem_cell_info *info, void *buf)
  1900	{
  1901		struct nvmem_cell_entry cell;
  1902		int rc;
  1903		ssize_t len;
  1904	
  1905		if (!nvmem)
  1906			return -EINVAL;
  1907	
  1908		/* Cells with read_post_process hook may realloc buffer we can't allow here */
  1909		if (info->read_post_process)
  1910			return -EINVAL;
  1911	
  1912		rc = nvmem_cell_info_to_nvmem_cell_entry_nodup(nvmem, info, &cell);
  1913		if (rc)
  1914			return rc;
  1915	
> 1916		rc = __nvmem_cell_read(nvmem, &cell, &buf, &cell.bytes, NULL, 0);
  1917		if (rc)
  1918			return rc;
  1919	
> 1920		return len;
  1921	}
  1922	EXPORT_SYMBOL_GPL(nvmem_device_cell_read);
  1923	

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests