Hi Ricardo, I love your patch! Perhaps something to improve: [auto build test WARNING on media-tree/master] [also build test WARNING on linus/master v5.19-rc2 next-20220617] [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/intel-lab-lkp/linux/commits/Ricardo-Ribalda/uvcvideo-Fix-handling-of-power_line_frequency/20220617-185644 base: git://linuxtv.org/media_tree.git master config: hexagon-randconfig-r045-20220617 (https://download.01.org/0day-ci/archive/20220617/202206172239.M4dQBUhz-lkp@xxxxxxxxx/config) compiler: clang version 15.0.0 (https://github.com/llvm/llvm-project d764aa7fc6b9cc3fbe960019018f5f9e941eb0a6) 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/intel-lab-lkp/linux/commit/10bdca4191d7a8be97c77dbe4ba89c05713ee0e2 git remote add linux-review https://github.com/intel-lab-lkp/linux git fetch --no-tags linux-review Ricardo-Ribalda/uvcvideo-Fix-handling-of-power_line_frequency/20220617-185644 git checkout 10bdca4191d7a8be97c77dbe4ba89c05713ee0e2 # save the config file mkdir build_dir && cp config build_dir/.config COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=hexagon SHELL=/bin/bash drivers/media/usb/uvc/ If you fix the issue, kindly add following tag where applicable Reported-by: kernel test robot <lkp@xxxxxxxxx> All warnings (new ones prefixed by >>): >> drivers/media/usb/uvc/uvc_ctrl.c:2442:6: warning: variable 'mapping' is used uninitialized whenever 'if' condition is false [-Wsometimes-uninitialized] if (chain->dev->info->mappings) { ^~~~~~~~~~~~~~~~~~~~~~~~~~ drivers/media/usb/uvc/uvc_ctrl.c:2459:9: note: uninitialized use occurs here mend = mapping + ARRAY_SIZE(uvc_ctrl_mappings); ^~~~~~~ drivers/media/usb/uvc/uvc_ctrl.c:2442:2: note: remove the 'if' if its condition is always true if (chain->dev->info->mappings) { ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ drivers/media/usb/uvc/uvc_ctrl.c:2406:43: note: initialize the variable 'mapping' to silence this warning const struct uvc_control_mapping *mapping; ^ = NULL 1 warning generated. vim +2442 drivers/media/usb/uvc/uvc_ctrl.c 2396 2397 /* 2398 * Add control information and hardcoded stock control mappings to the given 2399 * device. 2400 */ 2401 static void uvc_ctrl_init_ctrl(struct uvc_video_chain *chain, 2402 struct uvc_control *ctrl) 2403 { 2404 const struct uvc_control_info *info = uvc_ctrls; 2405 const struct uvc_control_info *iend = info + ARRAY_SIZE(uvc_ctrls); 2406 const struct uvc_control_mapping *mapping; 2407 const struct uvc_control_mapping *mend; 2408 2409 /* XU controls initialization requires querying the device for control 2410 * information. As some buggy UVC devices will crash when queried 2411 * repeatedly in a tight loop, delay XU controls initialization until 2412 * first use. 2413 */ 2414 if (UVC_ENTITY_TYPE(ctrl->entity) == UVC_VC_EXTENSION_UNIT) 2415 return; 2416 2417 for (; info < iend; ++info) { 2418 if (uvc_entity_match_guid(ctrl->entity, info->entity) && 2419 ctrl->index == info->index) { 2420 uvc_ctrl_add_info(chain->dev, ctrl, info); 2421 /* 2422 * Retrieve control flags from the device. Ignore errors 2423 * and work with default flag values from the uvc_ctrl 2424 * array when the device doesn't properly implement 2425 * GET_INFO on standard controls. 2426 */ 2427 uvc_ctrl_get_flags(chain->dev, ctrl, &ctrl->info); 2428 break; 2429 } 2430 } 2431 2432 if (!ctrl->initialized) 2433 return; 2434 2435 /* 2436 * First check if the device provides a custom mapping for this control, 2437 * used to override standard mappings for non-conformant devices. Don't 2438 * process standard mappings if a custom mapping is found. This 2439 * mechanism doesn't support combining standard and custom mappings for 2440 * a single control. 2441 */ > 2442 if (chain->dev->info->mappings) { 2443 bool custom = false; 2444 unsigned int i; 2445 2446 for (i = 0; (mapping = chain->dev->info->mappings[i]); ++i) { 2447 if (uvc_entity_match_guid(ctrl->entity, mapping->entity) && 2448 ctrl->info.selector == mapping->selector) { 2449 __uvc_ctrl_add_mapping(chain, ctrl, mapping); 2450 custom = true; 2451 } 2452 } 2453 2454 if (custom) 2455 return; 2456 } 2457 2458 /* Process common mappings next. */ 2459 mend = mapping + ARRAY_SIZE(uvc_ctrl_mappings); 2460 for (mapping = uvc_ctrl_mappings; mapping < mend; ++mapping) { 2461 if (uvc_entity_match_guid(ctrl->entity, mapping->entity) && 2462 ctrl->info.selector == mapping->selector) 2463 __uvc_ctrl_add_mapping(chain, ctrl, mapping); 2464 } 2465 2466 /* Finally process version-specific mappings. */ 2467 if (chain->dev->uvc_version < 0x0150) { 2468 mapping = uvc_ctrl_mappings_uvc11; 2469 mend = mapping + ARRAY_SIZE(uvc_ctrl_mappings_uvc11); 2470 } else { 2471 mapping = uvc_ctrl_mappings_uvc15; 2472 mend = mapping + ARRAY_SIZE(uvc_ctrl_mappings_uvc15); 2473 } 2474 2475 for (; mapping < mend; ++mapping) { 2476 if (uvc_entity_match_guid(ctrl->entity, mapping->entity) && 2477 ctrl->info.selector == mapping->selector) 2478 __uvc_ctrl_add_mapping(chain, ctrl, mapping); 2479 } 2480 } 2481 -- 0-DAY CI Kernel Test Service https://01.org/lkp
