[kbuild-all] [chrome-os:chromeos-4.19 27/50] drivers/gpu/drm/drm_hdcp.c:235:6: warning: no previous prototype for function 'drm_hdcp_request_srm'

tree: https://chromium.googlesource.com/chromiumos/third_party/kernel chromeos-4.19 head: b9a3f5405fb3783912a70780b9f51b8942feed91 commit: 9602e2b071719b0f1e22a3a9ea2f5f3a6ba8f272 [27/50] UPSTREAM: drm: revocation check at drm subsystem config: x86_64-randconfig-a005-20201113 (attached as .config) compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project 9e0c35655b6e8186baef8840b26ba4090503b554) 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 x86_64 cross compiling tool for clang build # apt-get install binutils-x86-64-linux-gnu git remote add chrome-os https://chromium.googlesource.com/chromiumos/third_party/kernel git fetch --no-tags chrome-os chromeos-4.19 git checkout 9602e2b071719b0f1e22a3a9ea2f5f3a6ba8f272 # 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 <lkp(a)intel.com&gt; All warnings (new ones prefixed by >>): void drm_hdcp_request_srm(struct drm_device *drm_dev) ^ drivers/gpu/drm/drm_hdcp.c:235:1: note: declare 'static' if the function is not intended to be used outside of this translation unit void drm_hdcp_request_srm(struct drm_device *drm_dev) ^ static int drm_setup_hdcp_srm(struct class *drm_class) ^ drivers/gpu/drm/drm_hdcp.c:317:1: note: declare 'static' if the function is not intended to be used outside of this translation unit int drm_setup_hdcp_srm(struct class *drm_class) ^ static void drm_teardown_hdcp_srm(struct class *drm_class) ^ drivers/gpu/drm/drm_hdcp.c:327:1: note: declare 'static' if the function is not intended to be used outside of this translation unit void drm_teardown_hdcp_srm(struct class *drm_class) ^ static 3 warnings generated. vim +/drm_hdcp_request_srm +235 drivers/gpu/drm/drm_hdcp.c 234 236 { 237 char fw_name[36] = "display_hdcp_srm.bin"; 238 const struct firmware *fw; 239 240 int ret; 241 242 ret = request_firmware_direct(&fw, (const char *)fw_name, 243 drm_dev->dev); 244 if (ret < 0) 245 goto exit; 246 247 if (fw->size && fw->data) 248 drm_hdcp_srm_update(fw->data, fw->size); 249 250 exit: 251 release_firmware(fw); 252 } 253 254 /** 255 * drm_hdcp_check_ksvs_revoked - Check the revoked status of the IDs 256 * 257 * @drm_dev: drm_device for which HDCP revocation check is requested 258 * @ksvs: List of KSVs (HDCP receiver IDs) 259 * @ksv_count: KSV count passed in through @ksvs 260 * 261 * This function reads the HDCP System renewability Message(SRM Table) 262 * from userspace as a firmware and parses it for the revoked HDCP 263 * KSVs(Receiver IDs) detected by DCP LLC. Once the revoked KSVs are known, 264 * revoked state of the KSVs in the list passed in by display drivers are 265 * decided and response is sent. 266 * 267 * SRM should be presented in the name of "display_hdcp_srm.bin". 268 * 269 * Returns: 270 * TRUE on any of the KSV is revoked, else FALSE. 271 */ 272 bool drm_hdcp_check_ksvs_revoked(struct drm_device *drm_dev, u8 *ksvs, 273 u32 ksv_count) 274 { 275 u32 rev_ksv_cnt, cnt, i, j; 276 u8 *rev_ksv_list; 277 278 if (!srm_data) 279 return false; 280 281 mutex_lock(&srm_data->mutex); 282 drm_hdcp_request_srm(drm_dev); 283 284 rev_ksv_cnt = srm_data->revoked_ksv_cnt; 285 rev_ksv_list = srm_data->revoked_ksv_list; 286 287 /* If the Revoked ksv list is empty */ 288 if (!rev_ksv_cnt || !rev_ksv_list) { 289 mutex_unlock(&srm_data->mutex); 290 return false; 291 } 292 293 for (cnt = 0; cnt < ksv_count; cnt++) { 294 rev_ksv_list = srm_data->revoked_ksv_list; 295 for (i = 0; i < rev_ksv_cnt; i++) { 296 for (j = 0; j < DRM_HDCP_KSV_LEN; j++) 297 if (ksvs[j] != rev_ksv_list[j]) { 298 break; 299 } else if (j == (DRM_HDCP_KSV_LEN - 1)) { 300 DRM_DEBUG("Revoked KSV is "); 301 drm_hdcp_print_ksv(ksvs); 302 mutex_unlock(&srm_data->mutex); 303 return true; 304 } 305 /* Move the offset to next KSV in the revoked list */ 306 rev_ksv_list += DRM_HDCP_KSV_LEN; 307 } 308 309 /* Iterate to next ksv_offset */ 310 ksvs += DRM_HDCP_KSV_LEN; 311 } 312 mutex_unlock(&srm_data->mutex); 313 return false; 314 } 315 EXPORT_SYMBOL_GPL(drm_hdcp_check_ksvs_revoked); 316 318 { 319 srm_data = kzalloc(sizeof(*srm_data), GFP_KERNEL); 320 if (!srm_data) 321 return -ENOMEM; 322 mutex_init(&srm_data->mutex); 323 324 return 0; 325 } 326 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org