Hi,

I love your patch! Perhaps something to improve:

[auto build test WARNING on hwmon/hwmon-next]
[also build test WARNING on linux/master robh/for-next linus/master v5.8-rc2 next-20200624]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use  as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/0day-ci/linux/commits/alexandru-tachici-analog-com/hwmon-pmbus-adm1266-add-support/20200624-232203
base:   https://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging.git hwmon-next
config: mips-allyesconfig (attached as .config)
compiler: mips-linux-gcc (GCC) 9.3.0
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
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=mips 

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/hwmon/pmbus/adm1266.c:27:5: warning: no previous prototype for 'pmbus_block_xfer' [-Wmissing-prototypes]
      27 | int pmbus_block_xfer(struct i2c_client *client, u8 cmd, u8 w_len,
         |     ^~~~~~~~~~~~~~~~

vim +/pmbus_block_xfer +27 drivers/hwmon/pmbus/adm1266.c

    21	
    22	/* Different from Block Read as it sends data and waits for the slave to
    23	 * return a value dependent on that data. The protocol is simply a Write Block
    24	 * followed by a Read Block without the Read-Block command field and the
    25	 * Write-Block STOP bit.
    26	 */
  > 27	int pmbus_block_xfer(struct i2c_client *client, u8 cmd, u8 w_len,
    28			     u8 *data_w, u8 *data_r)
    29	{
    30		u8 write_buf[ADM1266_PMBUS_BLOCK_MAX + 2];
    31		struct i2c_msg msgs[2] = {
    32			{
    33				.addr = client->addr,
    34				.flags = 0,
    35				.buf = write_buf,
    36				.len = w_len + 2,
    37			},
    38			{
    39				.addr = client->addr,
    40				.flags = I2C_M_RD,
    41				.len = ADM1266_PMBUS_BLOCK_MAX + 2,
    42			}
    43		};
    44		u8 addr = 0;
    45		u8 crc = 0;
    46		int ret;
    47	
    48		msgs[0].buf[0] = cmd;
    49		msgs[0].buf[1] = w_len;
    50		memcpy(&msgs[0].buf[2], data_w, w_len);
    51	
    52		msgs[0].buf = i2c_get_dma_safe_msg_buf(&msgs[0], 1);
    53		if (!msgs[0].buf)
    54			return -ENOMEM;
    55	
    56		msgs[1].buf = i2c_get_dma_safe_msg_buf(&msgs[1], 1);
    57		if (!msgs[1].buf) {
    58			i2c_put_dma_safe_msg_buf(msgs[0].buf, &msgs[0], false);
    59			return -ENOMEM;
    60		}
    61	
    62		ret = i2c_transfer(client->adapter, msgs, 2);
    63		if (ret != 2) {
    64			ret = -EPROTO;
    65			goto cleanup;
    66		}
    67	
    68		if (client->flags & I2C_CLIENT_PEC) {
    69			addr = i2c_8bit_addr_from_msg(&msgs[0]);
    70			crc = crc8(pmbus_crc_table, &addr, 1, crc);
    71			crc = crc8(pmbus_crc_table, msgs[0].buf,  msgs[0].len, crc);
    72	
    73			addr = i2c_8bit_addr_from_msg(&msgs[1]);
    74			crc = crc8(pmbus_crc_table, &addr, 1, crc);
    75			crc = crc8(pmbus_crc_table, msgs[1].buf,  msgs[1].buf[0] + 1,
    76				   crc);
    77	
    78			if (crc != msgs[1].buf[msgs[1].buf[0] + 1]) {
    79				ret = -EBADMSG;
    80				goto cleanup;
    81			}
    82		}
    83	
    84		memcpy(data_r, &msgs[1].buf[1], msgs[1].buf[0]);
    85		ret = msgs[1].buf[0];
    86	
    87	cleanup:
    88		i2c_put_dma_safe_msg_buf(msgs[0].buf, &msgs[0], true);
    89		i2c_put_dma_safe_msg_buf(msgs[1].buf, &msgs[1], true);
    90	
    91		return ret;
    92	}
    93	

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