tree:   git://github.com/linux-chenxing/linux.git mstar_v5_14_rebase
head:   651efd0e52f225e60faa8b30f9768021e2104d3c
commit: e39640d415b9c96ba82e287dadb7b73138058c76 [123/352] ARM: mstar: MSC313 SPI driver
config: arm-allyesconfig (attached as .config)
compiler: arm-linux-gnueabi-gcc (GCC) 10.3.0
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
        # https://github.com/linux-chenxing/linux/commit/e39640d415b9c96ba82e287dadb7b73138058c76
        git remote add linux-chenxing git://github.com/linux-chenxing/linux.git
        git fetch --no-tags linux-chenxing mstar_v5_14_rebase
        git checkout e39640d415b9c96ba82e287dadb7b73138058c76
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-10.3.0 make.cross ARCH=arm 

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

All warnings (new ones prefixed by >>):

>> drivers/spi/spi-msc313.c:154:6: warning: no previous prototype for 'msc313_spi_set_cs' [-Wmissing-prototypes]
     154 | void msc313_spi_set_cs(struct spi_device *spi, bool enable){
         |      ^~~~~~~~~~~~~~~~~
   drivers/spi/spi-msc313.c: In function 'msc313_spi_remove':
   drivers/spi/spi-msc313.c:322:21: warning: unused variable 'spi' [-Wunused-variable]
     322 |  struct msc313_spi *spi = spi_master_get_devdata(master);
         |                     ^~~


vim +/msc313_spi_set_cs +154 drivers/spi/spi-msc313.c

   153	
 > 154	void msc313_spi_set_cs(struct spi_device *spi, bool enable){
   155		struct msc313_spi *mspi = spi_master_get_devdata(spi->master);
   156		if(enable)
   157			regmap_update_bits(mspi->regmap, REG_CS, CS_MASK, CS_MASK);
   158		else
   159			regmap_update_bits(mspi->regmap, REG_CS, CS_MASK, 0);
   160	}
   161	

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org