Hi Xin, Thank you for the patch! Perhaps something to improve: [auto build test WARNING on robh/for-next] [also build test WARNING on linux/master linus/master v5.12-rc3 next-20210318] [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/Xin-Ji/Add-MIPI-rx-DPI-support/2... base: https://git.kernel.org/pub/scm/linux/kernel/git/robh/linux.git for-next config: arm-randconfig-r014-20210318 (attached as .config) compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project fcc1ce00931751ac02498986feb37744e9ace8de) 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 arm cross compiling tool for clang build # apt-get install binutils-arm-linux-gnueabi # https://github.com/0day-ci/linux/commit/348257d12d5c847255eaf814081fe996a... git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Xin-Ji/Add-MIPI-rx-DPI-support/20210319-104013 git checkout 348257d12d5c847255eaf814081fe996aeab1841 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=arm 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 >>): if (ep0) { ^~~ drivers/gpu/drm/bridge/analogix/anx7625.c:1343:22: note: uninitialized use occurs here pdata->mipi_lanes = mipi_lanes; ^~~~~~~~~~ drivers/gpu/drm/bridge/analogix/anx7625.c:1333:2: note: remove the 'if' if its condition is always true if (ep0) { ^~~~~~~~~ drivers/gpu/drm/bridge/analogix/anx7625.c:1321:26: note: initialize the variable 'mipi_lanes' to silence this warning int bus_type, mipi_lanes; ^ = 0 if (ep0) { ^~~ drivers/gpu/drm/bridge/analogix/anx7625.c:1340:6: note: uninitialized use occurs here if (bus_type == 5) /* bus type is Parallel(DSI) */ ^~~~~~~~ drivers/gpu/drm/bridge/analogix/anx7625.c:1333:2: note: remove the 'if' if its condition is always true if (ep0) { ^~~~~~~~~ drivers/gpu/drm/bridge/analogix/anx7625.c:1321:14: note: initialize the variable 'bus_type' to silence this warning int bus_type, mipi_lanes; ^ = 0 2 warnings generated. vim +1333 drivers/gpu/drm/bridge/analogix/anx7625.c 1314 1315 static int anx7625_parse_dt(struct device *dev, 1316 struct anx7625_platform_data *pdata) 1317 { 1318 struct device_node *np = dev->of_node, *ep0; 1319 struct drm_panel *panel; 1320 int ret; 1321 int bus_type, mipi_lanes; 1322 1323 anx7625_get_swing_setting(dev, pdata); 1324 1325 pdata->is_dpi = 1; /* default dpi mode */ 1326 pdata->mipi_host_node = of_graph_get_remote_node(np, 0, 0); 1327 if (!pdata->mipi_host_node) { 1328 DRM_DEV_ERROR(dev, "fail to get internal panel.\n"); 1329 return -ENODEV; 1330 } 1331 1332 ep0 = of_graph_get_endpoint_by_regs(np, 0, 0); 1334 if (of_property_read_u32(ep0, "bus-type", &bus_type)) 1335 bus_type = 0; 1336 1337 mipi_lanes = of_property_count_u32_elems(ep0, "data-lanes"); 1338 } 1339 1340 if (bus_type == 5) /* bus type is Parallel(DSI) */ 1341 pdata->is_dpi = 0; 1342 1343 pdata->mipi_lanes = mipi_lanes; 1344 if (pdata->mipi_lanes > MAX_LANES_SUPPORT || pdata->mipi_lanes <= 0) 1345 pdata->mipi_lanes = MAX_LANES_SUPPORT; 1346 1347 if (pdata->is_dpi) 1348 DRM_DEV_DEBUG_DRIVER(dev, "found MIPI DPI host node.\n"); 1349 else 1350 DRM_DEV_DEBUG_DRIVER(dev, "found MIPI DSI host node.\n"); 1351 1352 ret = drm_of_find_panel_or_bridge(np, 1, 0, &panel, NULL); 1353 if (ret < 0) { 1354 if (ret == -ENODEV) 1355 return 0; 1356 return ret; 1357 } 1358 if (!panel) 1359 return -ENODEV; 1360 1361 pdata->panel_bridge = devm_drm_panel_bridge_add(dev, panel); 1362 if (IS_ERR(pdata->panel_bridge)) 1363 return PTR_ERR(pdata->panel_bridge); 1364 DRM_DEV_DEBUG_DRIVER(dev, "get panel node.\n"); 1365 1366 return 0; 1367 } 1368 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org