From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-la0-f48.google.com ([209.85.215.48]:47454 "EHLO mail-la0-f48.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754495Ab3BDL4Q (ORCPT ); Mon, 4 Feb 2013 06:56:16 -0500 Subject: [PATCH v2 6/7] PCI/PM: warn about incomplete actions in ->runtime_suspend() callback To: e1000-devel@lists.sourceforge.net, linux-pci@vger.kernel.org, "Rafael J. Wysocki" , linux-kernel@vger.kernel.org From: Konstantin Khlebnikov Cc: Bjorn Helgaas Date: Mon, 04 Feb 2013 15:56:12 +0400 Message-ID: <20130204115612.5569.49895.stgit@zurg> In-Reply-To: <20130204115246.5569.85829.stgit@zurg> References: <20130204115246.5569.85829.stgit@zurg> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Sender: linux-pci-owner@vger.kernel.org List-ID: Documentation/power/pci.txt says: | It is expected that the device driver's pm->runtime_suspend() callback will | not attempt to prepare the device for signaling wakeup or to put it into a | low-power state. The driver ought to leave these tasks to the PCI subsystem | that has all of the information necessary to perform them. After commit 42eca2302146fed51335b95128e949ee6f54478f ("PCI: Don't touch card regs after runtime suspend D3") | If the driver takes care of state saving, don't touch any registers on it. pci_pm_runtime_suspend() thinks if state has been saved by ->runtime_suspend() that means device alredy prepared for wakeup and probably no longer accessible. Thus driver must either do all actions or leave all these tasks to PCI subsystem. Signed-off-by: Konstantin Khlebnikov Cc: Rafael J. Wysocki Cc: Bjorn Helgaas Cc: linux-pci@vger.kernel.org --- drivers/pci/pci-driver.c | 15 +++++++++++---- 1 file changed, 11 insertions(+), 4 deletions(-) diff --git a/drivers/pci/pci-driver.c b/drivers/pci/pci-driver.c index f9aa311..2b0ff9a 100644 --- a/drivers/pci/pci-driver.c +++ b/drivers/pci/pci-driver.c @@ -1009,12 +1009,19 @@ static int pci_pm_runtime_suspend(struct device *dev) return 0; } - if (!pci_dev->state_saved) { - pci_save_state(pci_dev); - pci_finish_runtime_suspend(pci_dev); + if (pci_dev->state_saved) { + WARN_ONCE(pci_dev->current_state == prev, + "PCI PM: Power state of device not changed by %pF\n", + pm->runtime_suspend); + WARN_ONCE(pci_dev_run_wake(pci_dev) && + !pci_dev->wakeup_prepared, + "PCI PM: Waking of device not configured by %pF\n", + pm->runtime_suspend); + return 0; } - return 0; + pci_save_state(pci_dev); + return pci_finish_runtime_suspend(pci_dev); } static int pci_pm_runtime_resume(struct device *dev)