Hi Fangzhi, Thank you for the patch! Yet something to improve: [auto build test ERROR on drm-intel/for-linux-next] [also build test ERROR on drm-tip/drm-tip drm-exynos/exynos-drm-next tegra-drm/drm/tegra/for-next linus/master v5.14-rc7 next-20210827] [cannot apply to drm/drm-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/Fangzhi-Zuo/Update-128b-132b-MST-Slot-Information/20210828-082044 base: git://anongit.freedesktop.org/drm-intel for-linux-next config: x86_64-randconfig-a005-20210827 (attached as .config) compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project 4e1a164d7bd53653f79decc121afe784d2fde0a7) 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/9b4444b8b7cc43f098ef1f3a234c304c0e537754 git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Fangzhi-Zuo/Update-128b-132b-MST-Slot-Information/20210828-082044 git checkout 9b4444b8b7cc43f098ef1f3a234c304c0e537754 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=x86_64 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot All errors (new ones prefixed by >>): >> drivers/gpu/drm/amd/amdgpu/../display/amdgpu_dm/amdgpu_dm_mst_types.c:447:23: error: implicit declaration of function 'dc_link_dp_mst_decide_link_encoding_format' [-Werror,-Wimplicit-function-declaration] link_encoding_cap = dc_link_dp_mst_decide_link_encoding_format(aconnector->dc_link); ^ >> drivers/gpu/drm/amd/amdgpu/../display/amdgpu_dm/amdgpu_dm_mst_types.c:448:3: error: implicit declaration of function 'drm_dp_mst_update_coding_cap' [-Werror,-Wimplicit-function-declaration] drm_dp_mst_update_coding_cap(&aconnector->mst_mgr, link_encoding_cap); ^ 2 errors generated. vim +/dc_link_dp_mst_decide_link_encoding_format +447 drivers/gpu/drm/amd/amdgpu/../display/amdgpu_dm/amdgpu_dm_mst_types.c 441 442 void get_mst_link_encoding_cap(struct amdgpu_dm_connector *aconnector) 443 { 444 u8 link_encoding_cap; 445 446 if (aconnector->dc_link->type == dc_connection_mst_branch) { > 447 link_encoding_cap = dc_link_dp_mst_decide_link_encoding_format(aconnector->dc_link); > 448 drm_dp_mst_update_coding_cap(&aconnector->mst_mgr, link_encoding_cap); 449 } 450 } 451 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org