Hi Jeffrey, Thank you for the patch! Perhaps something to improve: [auto build test WARNING on linus/master] [also build test WARNING on v5.11 next-20210216] [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/Jeffrey-Hugo/mhi_bus-core-Wait-f... base: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git f40ddce88593482919761f74910f42f4b84c004b config: x86_64-randconfig-a013-20210216 (attached as .config) compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project c9439ca36342fb6013187d0a69aef92736951476) 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/a9148d0d4715fb099ae777ecd89a1d3fa... git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Jeffrey-Hugo/mhi_bus-core-Wait-for-ready-state-after-reset/20210217-045558 git checkout a9148d0d4715fb099ae777ecd89a1d3fab7eb7aa # 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 >>): cur_state == MHI_PM_SYS_ERR_PROCESS) { ^~~~~~~~~ drivers/bus/mhi/core/pm.c:451:2: note: variable 'cur_state' is declared here enum mhi_pm_state cur_state; ^ 1 warning generated. vim +/cur_state +501 drivers/bus/mhi/core/pm.c 447 448 /* Handle shutdown transitions */ 449 static void mhi_pm_disable_transition(struct mhi_controller *mhi_cntrl) 450 { 451 enum mhi_pm_state cur_state; 452 struct mhi_event *mhi_event; 453 struct mhi_cmd_ctxt *cmd_ctxt; 454 struct mhi_cmd *mhi_cmd; 455 struct mhi_event_ctxt *er_ctxt; 456 struct device *dev = &mhi_cntrl->mhi_dev->dev; 457 int ret, i; 458 459 dev_dbg(dev, "Processing disable transition with PM state: %s\n", 460 to_mhi_pm_state_str(mhi_cntrl->pm_state)); 461 462 mutex_lock(&mhi_cntrl->pm_mutex); 463 464 /* Trigger MHI RESET so that the device will not access host memory */ 465 if (!MHI_PM_IN_FATAL_STATE(mhi_cntrl->pm_state)) { 466 u32 in_reset = -1, ready = 0; 467 unsigned long timeout = msecs_to_jiffies(mhi_cntrl->timeout_ms); 468 469 dev_dbg(dev, "Triggering MHI Reset in device\n"); 470 mhi_set_mhi_state(mhi_cntrl, MHI_STATE_RESET); 471 472 /* Wait for the reset bit to be cleared by the device */ 473 ret = wait_event_timeout(mhi_cntrl->state_event, 474 mhi_read_reg_field(mhi_cntrl, 475 mhi_cntrl->regs, 476 MHICTRL, 477 MHICTRL_RESET_MASK, 478 MHICTRL_RESET_SHIFT, 479 &in_reset) || 480 !in_reset, timeout); 481 if (!ret || in_reset) 482 dev_err(dev, "Device failed to exit MHI Reset state\n"); 483 484 /* 485 * Device will clear BHI_INTVEC as a part of RESET processing, 486 * hence re-program it 487 */ 488 mhi_write_reg(mhi_cntrl, mhi_cntrl->bhi, BHI_INTVEC, 0); 489 490 if (!MHI_IN_PBL(mhi_get_exec_env(mhi_cntrl))) { 491 /* wait for ready to be set */ 492 ret = wait_event_timeout(mhi_cntrl->state_event, 493 mhi_read_reg_field(mhi_cntrl, 494 mhi_cntrl->regs, 495 MHISTATUS, 496 MHISTATUS_READY_MASK, 497 MHISTATUS_READY_SHIFT, 498 &ready) 499 || ready, timeout); 500 if ((!ret || !ready) && 502 dev_err(dev, 503 "Device failed to enter READY state\n"); 504 mutex_unlock(&mhi_cntrl->pm_mutex); 505 return; 506 } 507 } 508 } 509 510 dev_dbg(dev, 511 "Waiting for all pending event ring processing to complete\n"); 512 mhi_event = mhi_cntrl->mhi_event; 513 for (i = 0; i < mhi_cntrl->total_ev_rings; i++, mhi_event++) { 514 if (mhi_event->offload_ev) 515 continue; 516 free_irq(mhi_cntrl->irq[mhi_event->irq], mhi_event); 517 tasklet_kill(&mhi_event->task); 518 } 519 520 /* Release lock and wait for all pending threads to complete */ 521 mutex_unlock(&mhi_cntrl->pm_mutex); 522 dev_dbg(dev, "Waiting for all pending threads to complete\n"); 523 wake_up_all(&mhi_cntrl->state_event); 524 525 dev_dbg(dev, "Reset all active channels and remove MHI devices\n"); 526 device_for_each_child(&mhi_cntrl->mhi_dev->dev, NULL, mhi_destroy_device); 527 528 mutex_lock(&mhi_cntrl->pm_mutex); 529 530 WARN_ON(atomic_read(&mhi_cntrl->dev_wake)); 531 WARN_ON(atomic_read(&mhi_cntrl->pending_pkts)); 532 533 /* Reset the ev rings and cmd rings */ 534 dev_dbg(dev, "Resetting EV CTXT and CMD CTXT\n"); 535 mhi_cmd = mhi_cntrl->mhi_cmd; 536 cmd_ctxt = mhi_cntrl->mhi_ctxt->cmd_ctxt; 537 for (i = 0; i < NR_OF_CMD_RINGS; i++, mhi_cmd++, cmd_ctxt++) { 538 struct mhi_ring *ring = &mhi_cmd->ring; 539 540 ring->rp = ring->base; 541 ring->wp = ring->base; 542 cmd_ctxt->rp = cmd_ctxt->rbase; 543 cmd_ctxt->wp = cmd_ctxt->rbase; 544 } 545 546 mhi_event = mhi_cntrl->mhi_event; 547 er_ctxt = mhi_cntrl->mhi_ctxt->er_ctxt; 548 for (i = 0; i < mhi_cntrl->total_ev_rings; i++, er_ctxt++, 549 mhi_event++) { 550 struct mhi_ring *ring = &mhi_event->ring; 551 552 /* Skip offload events */ 553 if (mhi_event->offload_ev) 554 continue; 555 556 ring->rp = ring->base; 557 ring->wp = ring->base; 558 er_ctxt->rp = er_ctxt->rbase; 559 er_ctxt->wp = er_ctxt->rbase; 560 } 561 562 /* Move to disable state */ 563 write_lock_irq(&mhi_cntrl->pm_lock); 564 cur_state = mhi_tryset_pm_state(mhi_cntrl, MHI_PM_DISABLE); 565 write_unlock_irq(&mhi_cntrl->pm_lock); 566 if (unlikely(cur_state != MHI_PM_DISABLE)) 567 dev_err(dev, "Error moving from PM state: %s to: %s\n", 568 to_mhi_pm_state_str(cur_state), 569 to_mhi_pm_state_str(MHI_PM_DISABLE)); 570 571 dev_dbg(dev, "Exiting with PM state: %s, MHI state: %s\n", 572 to_mhi_pm_state_str(mhi_cntrl->pm_state), 573 TO_MHI_STATE_STR(mhi_cntrl->dev_state)); 574 575 mutex_unlock(&mhi_cntrl->pm_mutex); 576 } 577 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org