From patchwork Sun Sep 18 03:39:20 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lukas Wunner X-Patchwork-Id: 9337535 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 E6146601C2 for ; Sun, 18 Sep 2016 03:40:15 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id DABB728F03 for ; Sun, 18 Sep 2016 03:40:15 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id CDEE228F05; Sun, 18 Sep 2016 03:40:15 +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=ham 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 5116128EFA for ; Sun, 18 Sep 2016 03:40:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755868AbcIRDkN (ORCPT ); Sat, 17 Sep 2016 23:40:13 -0400 Received: from mailout3.hostsharing.net ([176.9.242.54]:45565 "EHLO mailout3.hostsharing.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755880AbcIRDkM (ORCPT ); Sat, 17 Sep 2016 23:40:12 -0400 Received: from h08.hostsharing.net (h08.hostsharing.net [83.223.95.28]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mailout3.hostsharing.net (Postfix) with ESMTPS id D151C101E9E73; Sun, 18 Sep 2016 05:40:09 +0200 (CEST) Received: from localhost (3-38-90-81.adsl.cmo.de [81.90.38.3]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA (128/128 bits)) (No client certificate requested) by h08.hostsharing.net (Postfix) with ESMTPSA id AFF63603E217; Sun, 18 Sep 2016 05:40:07 +0200 (CEST) X-Mailbox-Line: From 492d4d62ae1b3a95570babe9608d8ea971b62585 Mon Sep 17 00:00:00 2001 Message-Id: <492d4d62ae1b3a95570babe9608d8ea971b62585.1474130360.git.lukas@wunner.de> In-Reply-To: References: From: Lukas Wunner Date: Sun, 18 Sep 2016 05:39:20 +0200 Subject: [PATCH v2 2/5] PCI: Query platform firmware for device power state To: linux-pci@vger.kernel.org Cc: linux-pm@vger.kernel.org, linux-acpi@vger.kernel.org, "Rafael J. Wysocki" , Peter Wu , Andreas Noever Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Usually the most accurate way to determine a PCI device's power state is to read its PM Control & Status Register. There are two cases however when this is not an option: If the device doesn't have the PM capability at all, or if it is in D3cold (in which case its config space is inaccessible). In both cases, we can alternatively query the platform firmware for its opinion on the device's power state. To facilitate this, augment struct pci_platform_pm_ops with a ->get_power callback and implement it for acpi_pci_platform_pm (the only pci_platform_pm_ops existing so far). It is used by a forthcoming commit to let pci_update_current_state() recognize D3cold. Cc: Rafael J. Wysocki Signed-off-by: Lukas Wunner Acked-by: Rafael J. Wysocki --- Changes since v1: * In acpi_pci_get_power_state(), only check for ACPI_STATE_UNKNOWN instead of ACPI_STATE_D0 and ACPI_STATE_D3_COLD. * Move the change to pci_update_current_state() to new patch [3/5]. drivers/pci/pci-acpi.c | 22 ++++++++++++++++++++++ drivers/pci/pci.c | 10 ++++++++-- drivers/pci/pci.h | 3 +++ 3 files changed, 33 insertions(+), 2 deletions(-) diff --git a/drivers/pci/pci-acpi.c b/drivers/pci/pci-acpi.c index 9a033e8..d966d47 100644 --- a/drivers/pci/pci-acpi.c +++ b/drivers/pci/pci-acpi.c @@ -452,6 +452,27 @@ static int acpi_pci_set_power_state(struct pci_dev *dev, pci_power_t state) return error; } +static pci_power_t acpi_pci_get_power_state(struct pci_dev *dev) +{ + struct acpi_device *adev = ACPI_COMPANION(&dev->dev); + static const pci_power_t state_conv[] = { + [ACPI_STATE_D0] = PCI_D0, + [ACPI_STATE_D1] = PCI_D1, + [ACPI_STATE_D2] = PCI_D2, + [ACPI_STATE_D3_HOT] = PCI_D3hot, + [ACPI_STATE_D3_COLD] = PCI_D3cold, + }; + int state; + + if (!adev || !acpi_device_power_manageable(adev)) + return PCI_UNKNOWN; + + if (acpi_device_get_power(adev, &state) || state == ACPI_STATE_UNKNOWN) + return PCI_UNKNOWN; + + return state_conv[state]; +} + static bool acpi_pci_can_wakeup(struct pci_dev *dev) { struct acpi_device *adev = ACPI_COMPANION(&dev->dev); @@ -534,6 +555,7 @@ static bool acpi_pci_need_resume(struct pci_dev *dev) static const struct pci_platform_pm_ops acpi_pci_platform_pm = { .is_manageable = acpi_pci_power_manageable, .set_state = acpi_pci_set_power_state, + .get_state = acpi_pci_get_power_state, .choose_state = acpi_pci_choose_state, .sleep_wake = acpi_pci_sleep_wake, .run_wake = acpi_pci_run_wake, diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 72a9d3a..6ea0d2d 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -552,8 +552,9 @@ static const struct pci_platform_pm_ops *pci_platform_pm; int pci_set_platform_pm(const struct pci_platform_pm_ops *ops) { - if (!ops->is_manageable || !ops->set_state || !ops->choose_state || - !ops->sleep_wake || !ops->run_wake || !ops->need_resume) + if (!ops->is_manageable || !ops->set_state || !ops->get_state || + !ops->choose_state || !ops->sleep_wake || !ops->run_wake || + !ops->need_resume) return -EINVAL; pci_platform_pm = ops; return 0; @@ -570,6 +571,11 @@ static inline int platform_pci_set_power_state(struct pci_dev *dev, return pci_platform_pm ? pci_platform_pm->set_state(dev, t) : -ENOSYS; } +static inline pci_power_t platform_pci_get_power_state(struct pci_dev *dev) +{ + return pci_platform_pm ? pci_platform_pm->get_state(dev) : PCI_UNKNOWN; +} + static inline pci_power_t platform_pci_choose_state(struct pci_dev *dev) { return pci_platform_pm ? diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h index 194521b..4518562 100644 --- a/drivers/pci/pci.h +++ b/drivers/pci/pci.h @@ -42,6 +42,8 @@ int pci_probe_reset_function(struct pci_dev *dev); * * @set_state: invokes the platform firmware to set the device's power state * + * @get_state: queries the platform firmware for a device's current power state + * * @choose_state: returns PCI power state of given device preferred by the * platform; to be used during system-wide transitions from a * sleeping state to the working state and vice versa @@ -62,6 +64,7 @@ int pci_probe_reset_function(struct pci_dev *dev); struct pci_platform_pm_ops { bool (*is_manageable)(struct pci_dev *dev); int (*set_state)(struct pci_dev *dev, pci_power_t state); + pci_power_t (*get_state)(struct pci_dev *dev); pci_power_t (*choose_state)(struct pci_dev *dev); int (*sleep_wake)(struct pci_dev *dev, bool enable); int (*run_wake)(struct pci_dev *dev, bool enable);