drivers/hid/hid-ft260.c:879:1: warning: taking address of packed member 'clock' of class or structure 'ft260_get_i2c_status_report' may result in an unaligned pointer value

[kernel test robot <lkp@intel.com>]

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head:   c9e6606c7fe92b50a02ce51dda82586ebdf99b48
commit: 6a82582d9fa438045191074856f47165334f2777 HID: ft260: add usb hid to i2c host bridge driver
date:   10 months ago
config: mips-randconfig-r036-20220105 (https://download.01.org/0day-ci/archive/20220105/202201052330.GECx4YSO-lkp@intel.com/config)
compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project d5b6e30ed3acad794dd0aec400e617daffc6cc3d)
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 mips cross compiling tool for clang build
        # apt-get install binutils-mips-linux-gnu
        # https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=6a82582d9fa438045191074856f47165334f2777
        git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
        git fetch --no-tags linus master
        git checkout 6a82582d9fa438045191074856f47165334f2777
        # save the config file to linux build tree
        mkdir build_dir
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=mips SHELL=/bin/bash drivers/hid/ drivers/usb/gadget/ fs/

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/hid/hid-ft260.c:515:59: warning: variable 'len' is uninitialized when used here [-Wuninitialized]
                   hid_err(hdev, "%s: unsupported wr len: %d\n", __func__, len);
                                                                           ^~~
   include/linux/hid.h:1190:30: note: expanded from macro 'hid_err'
           dev_err(&(hid)->dev, fmt, ##__VA_ARGS__)
                                       ^~~~~~~~~~~
   include/linux/dev_printk.h:112:32: note: expanded from macro 'dev_err'
           _dev_err(dev, dev_fmt(fmt), ##__VA_ARGS__)
                                         ^~~~~~~~~~~
   drivers/hid/hid-ft260.c:507:9: note: initialize the variable 'len' to silence this warning
           int len, ret;
                  ^
                   = 0
>> drivers/hid/hid-ft260.c:879:1: warning: taking address of packed member 'clock' of class or structure 'ft260_get_i2c_status_report' may result in an unaligned pointer value [-Waddress-of-packed-member]
   FT260_I2CST_ATTR_SHOW(clock);
   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
   drivers/hid/hid-ft260.c:814:3: note: expanded from macro 'FT260_I2CST_ATTR_SHOW'
                   FT260_ATTR_SHOW(name, ft260_get_i2c_status_report,             \
                   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   drivers/hid/hid-ft260.c:803:18: note: expanded from macro 'FT260_ATTR_SHOW'
                   type *field = &rep.name;                                       \
                                  ^~~~~~~~
   2 warnings generated.


vim +879 drivers/hid/hid-ft260.c

   878	
 > 879	FT260_I2CST_ATTR_SHOW(clock);
   880	FT260_WORD_ATTR_STORE(clock, ft260_set_i2c_speed_report,
   881			      FT260_SET_I2C_CLOCK_SPEED);
   882	static DEVICE_ATTR_RW(clock);
   883	

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