tree: https://git.kernel.org/pub/scm/linux/kernel/git/sashal/linux-stable.git queue-5.4 head: d2c5af89e80c5b71f1da59879464a930947306a2 commit: e2bf810d1ab3ed29b696968b2b4cceb58f2f5bad [92/132] drm/panel: add panel driver for Elida KD35T133 panels config: i386-randconfig-s001-20210318 (attached as .config) compiler: gcc-9 (Debian 9.3.0-22) 9.3.0 reproduce: # apt-get install sparse # sparse version: v0.6.3-277-gc089cd2d-dirty # https://git.kernel.org/pub/scm/linux/kernel/git/sashal/linux-stable.git/c... git remote add sashal-linux-stable https://git.kernel.org/pub/scm/linux/kernel/git/sashal/linux-stable.git git fetch --no-tags sashal-linux-stable queue-5.4 git checkout e2bf810d1ab3ed29b696968b2b4cceb58f2f5bad # save the attached .config to linux build tree make W=1 C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' ARCH=i386 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; sparse warnings: (new ones prefixed by >>) drivers/gpu/drm/panel/panel-elida-kd35t133.c:233:27: sparse: expected int ( *get_modes )( ... ) drivers/gpu/drm/panel/panel-elida-kd35t133.c:233:27: sparse: got int ( * )( ... ) drivers/gpu/drm/panel/panel-elida-kd35t133.c:284:15: sparse: sparse: undefined identifier 'drm_panel_of_backlight' vim +233 drivers/gpu/drm/panel/panel-elida-kd35t133.c 229 230 static const struct drm_panel_funcs kd35t133_funcs = { 231 .unprepare = kd35t133_unprepare, 232 .prepare = kd35t133_prepare, 234 }; 235 236 static int kd35t133_probe(struct mipi_dsi_device *dsi) 237 { 238 struct device *dev = &dsi->dev; 239 struct kd35t133 *ctx; 240 int ret; 241 242 ctx = devm_kzalloc(dev, sizeof(*ctx), GFP_KERNEL); 243 if (!ctx) 244 return -ENOMEM; 245 246 ctx->reset_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_LOW); 247 if (IS_ERR(ctx->reset_gpio)) { 248 DRM_DEV_ERROR(dev, "cannot get reset gpio\n"); 249 return PTR_ERR(ctx->reset_gpio); 250 } 251 252 ctx->vdd = devm_regulator_get(dev, "vdd"); 253 if (IS_ERR(ctx->vdd)) { 254 ret = PTR_ERR(ctx->vdd); 255 if (ret != -EPROBE_DEFER) 256 DRM_DEV_ERROR(dev, 257 "Failed to request vdd regulator: %d\n", 258 ret); 259 return ret; 260 } 261 262 ctx->iovcc = devm_regulator_get(dev, "iovcc"); 263 if (IS_ERR(ctx->iovcc)) { 264 ret = PTR_ERR(ctx->iovcc); 265 if (ret != -EPROBE_DEFER) 266 DRM_DEV_ERROR(dev, 267 "Failed to request iovcc regulator: %d\n", 268 ret); 269 return ret; 270 } 271 272 mipi_dsi_set_drvdata(dsi, ctx); 273 274 ctx->dev = dev; 275 276 dsi->lanes = 1; 277 dsi->format = MIPI_DSI_FMT_RGB888; 278 dsi->mode_flags = MIPI_DSI_MODE_VIDEO | MIPI_DSI_MODE_VIDEO_BURST | 279 MIPI_DSI_MODE_LPM | MIPI_DSI_MODE_EOT_PACKET; 280 282 DRM_MODE_CONNECTOR_DSI); 283 284 ret = drm_panel_of_backlight(&ctx->panel); 285 if (ret) 286 return ret; 287 288 drm_panel_add(&ctx->panel); 289 290 ret = mipi_dsi_attach(dsi); 291 if (ret < 0) { 292 DRM_DEV_ERROR(dev, "mipi_dsi_attach failed: %d\n", ret); 293 drm_panel_remove(&ctx->panel); 294 return ret; 295 } 296 297 return 0; 298 } 299 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org