Hi Ezequiel,

I love your patch! Perhaps something to improve:

[auto build test WARNING on linuxtv-media/master]
[also build test WARNING on v5.11-rc1 next-20201223]
[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/Ezequiel-Garcia/media-v4l2-async-Add-waiting-subdevices-debugfs/20201229-020838
base:   git://linuxtv.org/media_tree.git master
config: parisc-randconfig-s032-20201228 (attached as .config)
compiler: hppa-linux-gcc (GCC) 9.3.0
reproduce:
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # apt-get install sparse
        # sparse version: v0.6.3-184-g1b896707-dirty
        # https://github.com/0day-ci/linux/commit/6dd20991dbcacc09544c9b4fce904253171b9329
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Ezequiel-Garcia/media-v4l2-async-Add-waiting-subdevices-debugfs/20201229-020838
        git checkout 6dd20991dbcacc09544c9b4fce904253171b9329
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' ARCH=parisc 

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 >>):

   In file included from include/media/v4l2-subdev.h:14,
                    from drivers/media/test-drivers/vimc/vimc-scaler.c:12:
>> include/media/v4l2-async.h:145:35: warning: 'struct dentry' declared inside parameter list will not be visible outside of this definition or declaration
     145 | void v4l2_async_debug_init(struct dentry *debugfs_dir);
         |                                   ^~~~~~


vim +145 include/media/v4l2-async.h

   139	
   140	/**
   141	 * v4l2_async_debug_init - Initialize debugging tools.
   142	 *
   143	 * @debugfs_dir: pointer to the parent debugfs &struct dentry
   144	 */
 > 145	void v4l2_async_debug_init(struct dentry *debugfs_dir);
   146	

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