Hi Michael, I love your patch! Perhaps something to improve: [auto build test WARNING on usb/usb-testing] [also build test WARNING on peter-chen-usb/for-usb-next v5.16-rc1 next-20211116] [cannot apply to media-tree/master balbi-usb/testing/next] [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/Michael-Grzeschik/usb-gadget-uvc... base: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing config: nds32-buildonly-randconfig-r005-20211116 (attached as .config) compiler: nds32le-linux-gcc (GCC) 11.2.0 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/0day-ci/linux/commit/3227638d6b37451cc22e7ee61a3311ec3... git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Michael-Grzeschik/usb-gadget-uvc-use-configfs-entries-for-negotiation-and-v4l2-VIDIOCS/20211117-084501 git checkout 3227638d6b37451cc22e7ee61a3311ec3f6498ce # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.2.0 make.cross ARCH=nds32 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All warnings (new ones prefixed by >>): 52 | int uvc_v4l2_get_bytesperline(struct uvcg_format *uformat, | ^~~~~~~~~~~~~~~~~~~~~~~~~ drivers/usb/gadget/function/uvc_v4l2.c: In function '_uvc_v4l2_try_fmt': drivers/usb/gadget/function/uvc_v4l2.c:240:13: warning: unused variable 'i' [-Wunused-variable] 240 | int i = 0; | ^ In file included from drivers/usb/gadget/function/uvc_v4l2.c:29: At top level: drivers/usb/gadget/function/uvc_configfs.h:40:27: warning: 'uvcg_format_names' defined but not used [-Wunused-const-variable=] 40 | static const char * const uvcg_format_names[] = { | ^~~~~~~~~~~~~~~~~ vim +/uvc_v4l2_get_bytesperline +52 drivers/usb/gadget/function/uvc_v4l2.c 51 53 struct uvcg_frame *uframe) 54 { 55 struct uvcg_uncompressed *u; 56 57 if (uformat->type == UVCG_UNCOMPRESSED) { 58 u = to_uvcg_uncompressed(&uformat->group.cg_item); 59 if (!u) 60 return 0; 61 62 return u->desc.bBitsPerPixel * uframe->frame.w_width / 8; 63 } 64 65 return 0; 66 } 67 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org