Hi Qing,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on spi/for-next]
[also build test WARNING on robh/for-next linus/master v5.10-rc7 next-20201207]
[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]

url:    https://github.com/0day-ci/linux/commits/Qing-Zhang/spi-LS7A-Add-Loongson-LS7A-SPI-controller-driver-support/20201208-154822
base:   https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi.git for-next
config: x86_64-allyesconfig (attached as .config)
compiler: gcc-9 (Debian 9.3.0-15) 9.3.0
reproduce (this is a W=1 build):
        # https://github.com/0day-ci/linux/commit/6b2c3d42e1460dd3472a2c74d6a6c46d8693ce79
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Qing-Zhang/spi-LS7A-Add-Loongson-LS7A-SPI-controller-driver-support/20201208-154822
        git checkout 6b2c3d42e1460dd3472a2c74d6a6c46d8693ce79
        # save the attached .config to linux build tree
        make W=1 ARCH=x86_64 

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-ls7a.c: In function 'ls7a_spi_write_read':
>> drivers/spi/spi-ls7a.c:162:19: warning: variable 'ls7a_spi' set but not used [-Wunused-but-set-variable]
     162 |  struct ls7a_spi *ls7a_spi;
         |                   ^~~~~~~~

vim +/ls7a_spi +162 drivers/spi/spi-ls7a.c

   158	
   159	static unsigned int ls7a_spi_write_read(struct spi_device *spi,
   160						struct spi_transfer *xfer)
   161	{
 > 162		struct ls7a_spi *ls7a_spi;
   163		unsigned int count;
   164		const u8 *tx = xfer->tx_buf;
   165		u8 *rx = xfer->rx_buf;
   166	
   167		ls7a_spi = spi_master_get_devdata(spi->master);
   168		count = xfer->len;
   169	
   170		do {
   171			if (ls7a_spi_write_read_8bit(spi, &tx, &rx, count) < 0)
   172				goto out;
   173			count--;
   174		} while (count);
   175	
   176	out:
   177		return xfer->len - count;
   178	}
   179	

---
0-DAY CI Kernel Test Service, Intel Corporation
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