Merge "mhi: core: handle pm error state transition within fast suspend/resume" (5588462a) · Commits · e / devices / android_kernel_fairphone_FP4

drivers/bus/mhi/core/mhi_pm.c

+37 −4

Original line number	Diff line number	Diff line
		@@ -1218,11 +1218,17 @@ int mhi_pm_fast_suspend(struct mhi_controller *mhi_cntrl, bool notify_client)
		enum MHI_PM_STATE new_state;
		struct mhi_chan itr, tmp;

		if (mhi_cntrl->pm_state == MHI_PM_DISABLE)
		read_lock_bh(&mhi_cntrl->pm_lock);
		if (mhi_cntrl->pm_state == MHI_PM_DISABLE) {
		read_unlock_bh(&mhi_cntrl->pm_lock);
		return -EINVAL;
		}

		if (MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state))
		if (MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state)) {
		read_unlock_bh(&mhi_cntrl->pm_lock);
		return -EIO;
		}
		read_unlock_bh(&mhi_cntrl->pm_lock);

		/* do a quick check to see if any pending votes to keep us busy */
		if (atomic_read(&mhi_cntrl->pending_pkts)) {
		@@ -1250,6 +1256,12 @@ int mhi_pm_fast_suspend(struct mhi_controller *mhi_cntrl, bool notify_client)
		goto error_suspend;
		}

		/* check pm state before saving it */
		if (MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state)) {
		ret = -EIO;
		goto error_suspend;
		}

		/* anytime after this, we will resume thru runtime pm framework */
		MHI_LOG("Allowing Fast M3 transition\n");

		@@ -1399,17 +1411,23 @@ int mhi_pm_fast_resume(struct mhi_controller *mhi_cntrl, bool notify_client)
		struct mhi_event *mhi_event;
		int i;

		read_lock_bh(&mhi_cntrl->pm_lock);
		MHI_LOG("Entered with pm_state:%s dev_state:%s\n",
		to_mhi_pm_state_str(mhi_cntrl->pm_state),
		TO_MHI_STATE_STR(mhi_cntrl->dev_state));

		if (mhi_cntrl->pm_state == MHI_PM_DISABLE)
		if (mhi_cntrl->pm_state == MHI_PM_DISABLE) {
		read_unlock_bh(&mhi_cntrl->pm_lock);
		return 0;
		}

		if (MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state))
		if (MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state)) {
		read_unlock_bh(&mhi_cntrl->pm_lock);
		return -EIO;
		}

		MHI_ASSERT(mhi_cntrl->pm_state != MHI_PM_M3, "mhi_pm_state != M3");
		read_unlock_bh(&mhi_cntrl->pm_lock);

		/* notify any clients we're about to exit lpm */
		if (notify_client) {
		@@ -1423,10 +1441,19 @@ int mhi_pm_fast_resume(struct mhi_controller *mhi_cntrl, bool notify_client)
		/* do not process control events */
		tasklet_disable(&mhi_cntrl->mhi_event->task);

		/* check if we entered error state again before doing the restore */
		write_lock_irq(&mhi_cntrl->pm_lock);

		if (MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state)) {
		write_unlock_irq(&mhi_cntrl->pm_lock);
		tasklet_enable(&mhi_cntrl->mhi_event->task);
		return -EIO;
		}

		/* restore the states */
		mhi_cntrl->pm_state = mhi_cntrl->saved_pm_state;
		mhi_cntrl->dev_state = mhi_cntrl->saved_dev_state;

		write_unlock_irq(&mhi_cntrl->pm_lock);

		switch (mhi_cntrl->pm_state) {
		@@ -1438,6 +1465,12 @@ int mhi_pm_fast_resume(struct mhi_controller *mhi_cntrl, bool notify_client)
		mhi_cntrl->wake_get(mhi_cntrl, true);
		mhi_cntrl->wake_put(mhi_cntrl, true);
		read_unlock_bh(&mhi_cntrl->pm_lock);
		break;
		default:
		MHI_ERR("Unexpected PM state:%s after restore\n",
		to_mhi_pm_state_str(mhi_cntrl->pm_state));
		tasklet_enable(&mhi_cntrl->mhi_event->task);
		return -EIO;
		}

		/* now it's safe to process ctrl events */