Hi Andy, I love your patch! Yet something to improve: [auto build test ERROR on wsa/i2c/for-next] [also build test ERROR on v5.13-rc7 next-20210618] [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/Andy-Shevchenko/i2c-parport-Swit... base: https://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux.git i2c/for-next config: x86_64-randconfig-a016-20210621 (attached as .config) compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project e1adf90826a57b674eee79b071fb46c1f5683cd0) 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 # https://github.com/0day-ci/linux/commit/460eecb7fb1072dc8d5c7e5b3ecac6867... git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Andy-Shevchenko/i2c-parport-Switch-to-use-module_parport_driver/20210617-023152 git checkout 460eecb7fb1072dc8d5c7e5b3ecac6867957f2fa # 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 errors (new ones prefixed by >>): return -ENODEV; ^ ~~~~~~~ drivers/i2c/busses/i2c-parport.c:277:3: error: void function 'i2c_parport_attach' should not return a value [-Wreturn-type] return -ENODEV; ^ ~~~~~~~ 2 errors generated. vim +/i2c_parport_attach +272 drivers/i2c/busses/i2c-parport.c 263 264 static void i2c_parport_attach(struct parport *port) 265 { 266 struct i2c_par *adapter; 267 int i; 268 struct pardev_cb i2c_parport_cb; 269 270 if (type < 0) { 271 pr_warn("adapter type unspecified\n"); 273 } 274 275 if (type >= ARRAY_SIZE(adapter_parm)) { 276 pr_warn("invalid type (%d)\n", type); 277 return -ENODEV; 278 } 279 280 for (i = 0; i < MAX_DEVICE; i++) { 281 if (parport[i] == -1) 282 continue; 283 if (port->number == parport[i]) 284 break; 285 } 286 if (i == MAX_DEVICE) { 287 pr_debug("Not using parport%d.\n", port->number); 288 return; 289 } 290 291 adapter = kzalloc(sizeof(struct i2c_par), GFP_KERNEL); 292 if (!adapter) 293 return; 294 memset(&i2c_parport_cb, 0, sizeof(i2c_parport_cb)); 295 i2c_parport_cb.flags = PARPORT_FLAG_EXCL; 296 i2c_parport_cb.irq_func = i2c_parport_irq; 297 i2c_parport_cb.private = adapter; 298 299 pr_debug("attaching to %s\n", port->name); 300 parport_disable_irq(port); 301 adapter->pdev = parport_register_dev_model(port, "i2c-parport", 302 &i2c_parport_cb, i); 303 if (!adapter->pdev) { 304 pr_err("Unable to register with parport\n"); 305 goto err_free; 306 } 307 308 /* Fill the rest of the structure */ 309 adapter->adapter.owner = THIS_MODULE; 310 adapter->adapter.class = I2C_CLASS_HWMON; 311 strlcpy(adapter->adapter.name, "Parallel port adapter", 312 sizeof(adapter->adapter.name)); 313 adapter->algo_data = parport_algo_data; 314 /* Slow down if we can't sense SCL */ 315 if (!adapter_parm[type].getscl.val) { 316 adapter->algo_data.getscl = NULL; 317 adapter->algo_data.udelay = 50; /* ~10 kbps */ 318 } 319 adapter->algo_data.data = port; 320 adapter->adapter.algo_data = &adapter->algo_data; 321 adapter->adapter.dev.parent = port->physport->dev; 322 323 if (parport_claim_or_block(adapter->pdev) < 0) { 324 dev_err(&adapter->pdev->dev, 325 "Could not claim parallel port\n"); 326 goto err_unregister; 327 } 328 329 /* Reset hardware to a sane state (SCL and SDA high) */ 330 parport_setsda(port, 1); 331 parport_setscl(port, 1); 332 /* Other init if needed (power on...) */ 333 if (adapter_parm[type].init.val) { 334 line_set(port, 1, &adapter_parm[type].init); 335 /* Give powered devices some time to settle */ 336 msleep(100); 337 } 338 339 if (i2c_bit_add_bus(&adapter->adapter) < 0) { 340 dev_err(&adapter->pdev->dev, "Unable to register with I2C\n"); 341 goto err_unregister; 342 } 343 344 /* Setup SMBus alert if supported */ 345 if (adapter_parm[type].smbus_alert) { 346 struct i2c_client *ara; 347 348 ara = i2c_new_smbus_alert_device(&adapter->adapter, 349 &adapter->alert_data); 350 if (!IS_ERR(ara)) { 351 adapter->ara = ara; 352 parport_enable_irq(port); 353 } else { 354 dev_warn(&adapter->pdev->dev, 355 "Failed to register ARA client\n"); 356 } 357 } 358 359 /* Add the new adapter to the list */ 360 mutex_lock(&adapter_list_lock); 361 list_add_tail(&adapter->node, &adapter_list); 362 mutex_unlock(&adapter_list_lock); 363 return; 364 365 err_unregister: 366 parport_release(adapter->pdev); 367 parport_unregister_device(adapter->pdev); 368 err_free: 369 kfree(adapter); 370 } 371 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org