From patchwork Tue Aug 1 00:56:18 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Rafael J. Wysocki" X-Patchwork-Id: 9873521 X-Patchwork-Delegate: bhelgaas@google.com Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id B92A56038F for ; Tue, 1 Aug 2017 01:04:47 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id AE48B2837D for ; Tue, 1 Aug 2017 01:04:47 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id A337428524; Tue, 1 Aug 2017 01:04:47 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 1CF3D2837D for ; Tue, 1 Aug 2017 01:04:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751860AbdHABE3 (ORCPT ); Mon, 31 Jul 2017 21:04:29 -0400 Received: from cloudserver094114.home.net.pl ([79.96.170.134]:57489 "EHLO cloudserver094114.home.net.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751959AbdHABEZ (ORCPT ); Mon, 31 Jul 2017 21:04:25 -0400 Received: from 79.184.253.199.ipv4.supernova.orange.pl (79.184.253.199) (HELO aspire.rjw.lan) by serwer1319399.home.pl (79.96.170.134) with SMTP (IdeaSmtpServer 0.82) id c4bbd08869eb945d; Tue, 1 Aug 2017 03:04:23 +0200 From: "Rafael J. Wysocki" To: Linux PCI , Linux ACPI Cc: Linux PM , LKML , Mika Westerberg , Bjorn Helgaas , Andy Shevchenko Subject: [PATCH v3 3/3] ACPI / PCI / PM: Rework acpi_pci_propagate_wakeup() Date: Tue, 01 Aug 2017 02:56:18 +0200 Message-ID: <1916183.UEozbhaQct@aspire.rjw.lan> User-Agent: KMail/4.14.10 (Linux/4.12.0-rc1+; KDE/4.14.9; x86_64; ; ) In-Reply-To: <4690779.IRjbMOd2yB@aspire.rjw.lan> References: <3116391.JNS1F4DjTg@aspire.rjw.lan> <4853865.5aRGCM4CdQ@aspire.rjw.lan> <4690779.IRjbMOd2yB@aspire.rjw.lan> MIME-Version: 1.0 Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Rafael J. Wysocki The acpi_pci_propagate_wakeup() routine is there to handle cases in which PCI bridges (or PCIe ports) are expected to signal wakeup for devices below them, but currently it doesn't do that correctly. The problem is that acpi_pci_propagate_wakeup() uses acpi_pm_set_device_wakeup() for bridges and if that routine is called for multiple times to disable wakeup for the same device, it will disable it on the first invocation and the next calls will have no effect (it works analogously when called to enable wakeup, but that is not a problem). Now, say acpi_pci_propagate_wakeup() has been called for two different devices under the same bridge and it has called acpi_pm_set_device_wakeup() for that bridge each time. The bridge is now enabled to generate wakeup signals. Next, suppose that one of the devices below it resumes and acpi_pci_propagate_wakeup() is called to disable wakeup for that device. It will then call acpi_pm_set_device_wakeup() for the bridge and that will effectively disable remote wakeup for all devices under it even though some of them may still be suspended and remote wakeup may be expected to work for them. To address this (arguably theoretical) issue, allow wakeup.enable_count under struct acpi_device to grow beyond 1 in certain situations. In particular, allow that to happen in acpi_pci_propagate_wakeup() when wakeup is enabled or disabled for PCI bridges, so that wakeup is actually disabled for the bridge when all devices under it resume and not when just one of them does that. Signed-off-by: Rafael J. Wysocki Reviewed-by: Andy Shevchenko Reviewed-by: Mika Westerberg Acked-by: Bjorn Helgaas --- v2 -> v3: Follow the Bjorn's suggestion to un-inline acpi_pm_set_device_wakeup() and acpi_pm_set_bridge_wakeup() to avoid exporting __acpi_pm_set_device_wakeup() whose max_count argument is too much of an internal detail to be documented for use in non-core code clearly enough. I've retained the tags, because the changes are minor and don't affect the behavior, but if (some of all) the tags are not applicabe any more, please let me know. :-) --- drivers/acpi/device_pm.c | 72 ++++++++++++++++++++++++++++++++--------------- drivers/pci/pci-acpi.c | 4 +- include/acpi/acpi_bus.h | 5 +++ 3 files changed, 57 insertions(+), 24 deletions(-) Index: linux-pm/drivers/acpi/device_pm.c =================================================================== --- linux-pm.orig/drivers/acpi/device_pm.c +++ linux-pm/drivers/acpi/device_pm.c @@ -684,19 +684,8 @@ static void acpi_pm_notify_work_func(str static DEFINE_MUTEX(acpi_wakeup_lock); -/** - * acpi_device_wakeup_enable - Enable wakeup functionality for device. - * @adev: ACPI device to enable wakeup functionality for. - * @target_state: State the system is transitioning into. - * - * Enable the GPE associated with @adev so that it can generate wakeup signals - * for the device in response to external (remote) events and enable wakeup - * power for it. - * - * Callers must ensure that @adev is a valid ACPI device node before executing - * this function. - */ -static int acpi_device_wakeup_enable(struct acpi_device *adev, u32 target_state) +static int __acpi_device_wakeup_enable(struct acpi_device *adev, + u32 target_state, int max_count) { struct acpi_device_wakeup *wakeup = &adev->wakeup; acpi_status status; @@ -704,9 +693,12 @@ static int acpi_device_wakeup_enable(str mutex_lock(&acpi_wakeup_lock); - if (wakeup->enable_count > 0) + if (wakeup->enable_count >= max_count) goto out; + if (wakeup->enable_count > 0) + goto inc; + error = acpi_enable_wakeup_device_power(adev, target_state); if (error) goto out; @@ -718,6 +710,7 @@ static int acpi_device_wakeup_enable(str goto out; } +inc: wakeup->enable_count++; out: @@ -726,6 +719,23 @@ out: } /** + * acpi_device_wakeup_enable - Enable wakeup functionality for device. + * @adev: ACPI device to enable wakeup functionality for. + * @target_state: State the system is transitioning into. + * + * Enable the GPE associated with @adev so that it can generate wakeup signals + * for the device in response to external (remote) events and enable wakeup + * power for it. + * + * Callers must ensure that @adev is a valid ACPI device node before executing + * this function. + */ +static int acpi_device_wakeup_enable(struct acpi_device *adev, u32 target_state) +{ + return __acpi_device_wakeup_enable(adev, target_state, 1); +} + +/** * acpi_device_wakeup_disable - Disable wakeup functionality for device. * @adev: ACPI device to disable wakeup functionality for. * @@ -752,12 +762,8 @@ out: mutex_unlock(&acpi_wakeup_lock); } -/** - * acpi_pm_set_device_wakeup - Enable/disable remote wakeup for given device. - * @dev: Device to enable/disable to generate wakeup events. - * @enable: Whether to enable or disable the wakeup functionality. - */ -int acpi_pm_set_device_wakeup(struct device *dev, bool enable) +static int __acpi_pm_set_device_wakeup(struct device *dev, bool enable, + int max_count) { struct acpi_device *adev; int error; @@ -777,13 +783,35 @@ int acpi_pm_set_device_wakeup(struct dev return 0; } - error = acpi_device_wakeup_enable(adev, acpi_target_system_state()); + error = __acpi_device_wakeup_enable(adev, acpi_target_system_state(), + max_count); if (!error) dev_dbg(dev, "Wakeup enabled by ACPI\n"); return error; } -EXPORT_SYMBOL(acpi_pm_set_device_wakeup); + +/** + * acpi_pm_set_device_wakeup - Enable/disable remote wakeup for given device. + * @dev: Device to enable/disable to generate wakeup events. + * @enable: Whether to enable or disable the wakeup functionality. + */ +int acpi_pm_set_device_wakeup(struct device *dev, bool enable) +{ + return __acpi_pm_set_device_wakeup(dev, enable, 1); +} +EXPORT_SYMBOL_GPL(acpi_pm_set_device_wakeup); + +/** + * acpi_pm_set_bridge_wakeup - Enable/disable remote wakeup for given bridge. + * @dev: Bridge device to enable/disable to generate wakeup events. + * @enable: Whether to enable or disable the wakeup functionality. + */ +int acpi_pm_set_bridge_wakeup(struct device *dev, bool enable) +{ + return __acpi_pm_set_device_wakeup(dev, enable, INT_MAX); +} +EXPORT_SYMBOL_GPL(acpi_pm_set_bridge_wakeup); /** * acpi_dev_pm_low_power - Put ACPI device into a low-power state. Index: linux-pm/include/acpi/acpi_bus.h =================================================================== --- linux-pm.orig/include/acpi/acpi_bus.h +++ linux-pm/include/acpi/acpi_bus.h @@ -626,6 +626,7 @@ acpi_status acpi_remove_pm_notifier(stru bool acpi_pm_device_can_wakeup(struct device *dev); int acpi_pm_device_sleep_state(struct device *, int *, int); int acpi_pm_set_device_wakeup(struct device *dev, bool enable); +int acpi_pm_set_bridge_wakeup(struct device *dev, bool enable); #else static inline void acpi_pm_wakeup_event(struct device *dev) { @@ -656,6 +657,10 @@ static inline int acpi_pm_set_device_wak { return -ENODEV; } +static inline int acpi_pm_set_bridge_wakeup(struct device *dev, bool enable) +{ + return -ENODEV; +} #endif #ifdef CONFIG_ACPI_SLEEP Index: linux-pm/drivers/pci/pci-acpi.c =================================================================== --- linux-pm.orig/drivers/pci/pci-acpi.c +++ linux-pm/drivers/pci/pci-acpi.c @@ -573,7 +573,7 @@ static int acpi_pci_propagate_wakeup(str { while (bus->parent) { if (acpi_pm_device_can_wakeup(&bus->self->dev)) - return acpi_pm_set_device_wakeup(&bus->self->dev, enable); + return acpi_pm_set_bridge_wakeup(&bus->self->dev, enable); bus = bus->parent; } @@ -581,7 +581,7 @@ static int acpi_pci_propagate_wakeup(str /* We have reached the root bus. */ if (bus->bridge) { if (acpi_pm_device_can_wakeup(bus->bridge)) - return acpi_pm_set_device_wakeup(bus->bridge, enable); + return acpi_pm_set_bridge_wakeup(bus->bridge, enable); } return 0; }