Hi Mason,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on linus/master]
[cannot apply to v5.4-rc5 next-20191030]
[if your patch is applied to the wrong git tree, please drop us a note to help
improve the system. BTW, we also suggest to use '--base' option to specify the
base tree in git format-patch, please see https://stackoverflow.com/a/37406982]

url:    https://github.com/0day-ci/linux/commits/Mason-Yang/mtd-rawnand-Add-support-Macronix-Block-Protection-deep-power-down-mode/20191030-071757
base:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 23fdb198ae81f47a574296dab5167c5e136a02ba
reproduce:
        # apt-get install sparse
        # sparse version: v0.6.1-dirty
        make ARCH=x86_64 allmodconfig
        make C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__'

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


sparse warnings: (new ones prefixed by >>)

>> drivers/mtd/nand/raw/nand_macronix.c:142:5: sparse: sparse: symbol 'nand_power_down_op' was not declared. Should it be static?

Please review and possibly fold the followup patch.

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