From patchwork Mon Jan 8 14:49:26 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Adrian Hunter X-Patchwork-Id: 10149707 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 922D5601A1 for ; Mon, 8 Jan 2018 14:50:06 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 37C24289EB for ; Mon, 8 Jan 2018 14:50:06 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 3695F28A64; Mon, 8 Jan 2018 14:50:06 +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 A60CE289EB for ; Mon, 8 Jan 2018 14:50:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932963AbeAHOuB (ORCPT ); Mon, 8 Jan 2018 09:50:01 -0500 Received: from mga03.intel.com ([134.134.136.65]:46240 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932200AbeAHOuA (ORCPT ); Mon, 8 Jan 2018 09:50:00 -0500 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by orsmga103.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 08 Jan 2018 06:49:59 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.46,330,1511856000"; d="scan'208";a="8392229" Received: from ahunter-desktop.fi.intel.com (HELO [10.237.72.168]) ([10.237.72.168]) by fmsmga002.fm.intel.com with ESMTP; 08 Jan 2018 06:49:57 -0800 Subject: Re: [PATCH 1/9] mmc: sdhci-pci: Stop calling sdhci_enable_irq_wakeups() To: Ulf Hansson Cc: linux-mmc , Haridhar Kalvala , Linux PM , "Rafael J. Wysocki" , Geert Uytterhoeven References: <1513757933-11232-1-git-send-email-adrian.hunter@intel.com> <1513757933-11232-2-git-send-email-adrian.hunter@intel.com> From: Adrian Hunter Organization: Intel Finland Oy, Registered Address: PL 281, 00181 Helsinki, Business Identity Code: 0357606 - 4, Domiciled in Helsinki Message-ID: Date: Mon, 8 Jan 2018 16:49:26 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.5.0 MIME-Version: 1.0 In-Reply-To: Content-Language: en-US Sender: linux-mmc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-mmc@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP On 21/12/17 17:33, Ulf Hansson wrote: > + linux-pm, Rafael, Geert > > On 21 December 2017 at 15:25, Adrian Hunter wrote: >> On 21/12/17 16:15, Ulf Hansson wrote: >>> On 20 December 2017 at 09:18, Adrian Hunter wrote: >>>> sdhci_enable_irq_wakeups() is already called by sdhci_suspend_host() so >>>> sdhci-pci should not need to call it. However sdhci_suspend_host() only >>>> calls it if wakeups are enabled, and sdhci-pci does not enable them until >>>> after calling sdhci_suspend_host(). So move the calls to >>>> sdhci_pci_init_wakeup() before calling sdhci_suspend_host(), and >>>> stop calling sdhci_enable_irq_wakeups(). That results in some >>>> simplification because sdhci_pci_suspend_host() and >>>> __sdhci_pci_suspend_host() no longer need to be separate functions. >>>> >>>> Signed-off-by: Adrian Hunter >>>> --- >>>> drivers/mmc/host/sdhci-pci-core.c | 58 ++++++++++++++------------------------- >>>> 1 file changed, 21 insertions(+), 37 deletions(-) >>>> >>>> diff --git a/drivers/mmc/host/sdhci-pci-core.c b/drivers/mmc/host/sdhci-pci-core.c >>>> index 110c634cfb43..2ffc09f088ee 100644 >>>> --- a/drivers/mmc/host/sdhci-pci-core.c >>>> +++ b/drivers/mmc/host/sdhci-pci-core.c >>>> @@ -39,10 +39,29 @@ >>>> static void sdhci_pci_hw_reset(struct sdhci_host *host); >>>> >>>> #ifdef CONFIG_PM_SLEEP >>>> -static int __sdhci_pci_suspend_host(struct sdhci_pci_chip *chip) >>>> +static int sdhci_pci_init_wakeup(struct sdhci_pci_chip *chip) >>>> +{ >>>> + mmc_pm_flag_t pm_flags = 0; >>>> + int i; >>>> + >>>> + for (i = 0; i < chip->num_slots; i++) { >>>> + struct sdhci_pci_slot *slot = chip->slots[i]; >>>> + >>>> + if (slot) >>>> + pm_flags |= slot->host->mmc->pm_flags; >>>> + } >>>> + >>>> + return device_init_wakeup(&chip->pdev->dev, >>>> + (pm_flags & MMC_PM_KEEP_POWER) && >>>> + (pm_flags & MMC_PM_WAKE_SDIO_IRQ)); >>> >>> A couple of comments here. >>> >>> Wakeup settings shouldn't be changed during system suspend. That means >>> we shouldn't call device_init_wakeup() (or device_set_wakeup_enable() >>> for that matter) here. >>> >>> Instead, device_init_wakeup() should be called during ->probe(), while >>> device_set_wakeup_enable() should normally *not* have to be called at >>> all by drivers. There are a exceptions for device_set_wakeup_enable(), >>> however it should not have to be called during system suspend, at >>> least. >>> >>> Of course, I realize that you are not changing the behavior in this >>> regards in this patch, so I am fine this anyway. >>> >>> My point is, that the end result while doing this improvements in this >>> series, should strive to that device_init_wakeup() and >>> device_set_wakeup_enable() becomes used correctly. I don't think that >>> is the case, or is it? >> >> Unfortunately we don't find out what the SDIO driver wants to do (i.e >> pm_flags & MMC_PM_WAKE_SDIO_IRQ) until suspend. > > That's true! Of course, we need to be able to act on this, somehow. > >> >> I considered enabling wakeups by default but wasn't sure that would not >> increase power consumption in devices not expecting it. > > I understand the problem, believe me. However, I would rather like to > try to find a generic solution to these problems, else we will keep > abusing existing wakeups APIs. > > For your information, I have been working on several issues on how to > handle the "wakeup path" correctly, which is linked to this problem. > See a few quite small series for this below [1], [2]. > > I think the general problems can be described liked this: > > 1) The dev->power.wakeup_path flag doesn't get set for the device by > the PM core, in case device_set_wakeup_enable() is called from a > ->suspend() callback. That also means, that the parent device don't > get its >power.wakeup_path flag set in __device_suspend() by the PM > core, while this may be expected by upper layers (PM domains, middle > layers). > > 2) device_may_wakeup() doesn't tell us the hole story about the > wakeup. Only that is *may* be configured. :-) > So in cases when device_may_wakeup() returns true, we still have these > three conditions to consider, which we currently can't distinguish > between: > > *) The wakeup is configured and enabled, so the device should be > enabled in the wakeup path. > > **) The wakeup is configured and enabled, but as an out-band-wakeup > signal (like a GPIO IRQ). This means the device shouldn't be enabled > in the wakeup path. So what about just adding can_oob_wakeup and oob_wakeup i.e. > > ***) The wakeup isn't configured, thus disabled, because there are no > consumers of the wakeup IRQ registered (as may be the case for SDIO > IRQ). This also means the device shouldn't be enabled in the wakeup > path. > > Potentially, one could consider **) and ***) being treated in the same > way, via using an opt-out method, avoiding the wakeup path to be > enabled. Currently I have been thinking of adding an "OUT_BAND_WAKEUP" > driver PM flag, to deal with this, however there may be other > preferred options. > > Kind regards > Uffe > > [1] > https://www.spinics.net/lists/linux-renesas-soc/msg21421.html > [2] > https://www.spinics.net/lists/linux-renesas-soc/msg20122.html > (Actually the discussions there concluded that we may need an > "OUT_BAND_WAKEUP" flag instead) > --- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html diff --git a/drivers/base/power/sysfs.c b/drivers/base/power/sysfs.c index 0f651efc58a1..162a511286b7 100644 --- a/drivers/base/power/sysfs.c +++ b/drivers/base/power/sysfs.c @@ -323,23 +323,32 @@ static ssize_t pm_qos_no_power_off_store(struct device *dev, static ssize_t wakeup_show(struct device *dev, struct device_attribute *attr, char *buf) { - return sprintf(buf, "%s\n", device_can_wakeup(dev) - ? (device_may_wakeup(dev) ? _enabled : _disabled) - : ""); + return sprintf(buf, "%s\n", device_may_wakeup(dev) || + device_may_oob_wakeup(dev) ? _enabled : + device_can_wakeup(dev) || + device_can_oob_wakeup(dev) ? _disabled : + ""); } static ssize_t wakeup_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t n) { - if (!device_can_wakeup(dev)) + bool enable = false; + + if (!device_can_wakeup(dev) && !device_can_oob_wakeup(dev)) return -EINVAL; if (sysfs_streq(buf, _enabled)) - device_set_wakeup_enable(dev, 1); - else if (sysfs_streq(buf, _disabled)) - device_set_wakeup_enable(dev, 0); - else + enable = true; + else if (!sysfs_streq(buf, _disabled)) return -EINVAL; + + if (device_can_wakeup(dev)) + device_set_wakeup_enable(dev, enable); + + if (device_can_oob_wakeup(dev)) + device_set_oob_wakeup_enable(dev, enable); + return n; } diff --git a/drivers/base/power/wakeup.c b/drivers/base/power/wakeup.c index e73a081c6397..13e176edc3d7 100644 --- a/drivers/base/power/wakeup.c +++ b/drivers/base/power/wakeup.c @@ -392,6 +392,20 @@ int device_wakeup_disable(struct device *dev) } EXPORT_SYMBOL_GPL(device_wakeup_disable); +static void wakeup_sysfs_add_remove(struct device *dev, bool capable) +{ + if (device_is_registered(dev) && !list_empty(&dev->power.entry)) { + if (capable) { + int ret = wakeup_sysfs_add(dev); + + if (ret) + dev_info(dev, "Wakeup sysfs attributes not added\n"); + } else { + wakeup_sysfs_remove(dev); + } + } +} + /** * device_set_wakeup_capable - Set/reset device wakeup capability flag. * @dev: Device to handle. @@ -410,20 +424,35 @@ void device_set_wakeup_capable(struct device *dev, bool capable) return; dev->power.can_wakeup = capable; - if (device_is_registered(dev) && !list_empty(&dev->power.entry)) { - if (capable) { - int ret = wakeup_sysfs_add(dev); - - if (ret) - dev_info(dev, "Wakeup sysfs attributes not added\n"); - } else { - wakeup_sysfs_remove(dev); - } - } + wakeup_sysfs_add_remove(dev, capable); } EXPORT_SYMBOL_GPL(device_set_wakeup_capable); /** + * device_set_oob_wakeup_capable - Set/reset device oob wakeup capability flag. + * @dev: Device to handle. + * @capable: Whether or not @dev is capable of out-of-band wake up of the system + * from sleep. + * + * If @capable is set, set the @dev's power.can_oob_wakeup flag and add its + * wakeup-related attributes to sysfs. Otherwise, unset the @dev's + * power.can_oob_wakeup flag and remove its wakeup-related attributes from + * sysfs. + * + * This function may sleep and it can't be called from any context where + * sleeping is not allowed. + */ +void device_set_oob_wakeup_capable(struct device *dev, bool capable) +{ + if (!!dev->power.can_oob_wakeup == !!capable) + return; + + dev->power.can_oob_wakeup = capable; + wakeup_sysfs_add_remove(dev, capable); +} +EXPORT_SYMBOL_GPL(device_set_oob_wakeup_capable); + +/** * device_init_wakeup - Device wakeup initialization. * @dev: Device to handle. * @enable: Whether or not to enable @dev as a wakeup device. diff --git a/include/linux/pm.h b/include/linux/pm.h index e723b78d8357..22cfcacc0095 100644 --- a/include/linux/pm.h +++ b/include/linux/pm.h @@ -585,6 +585,8 @@ struct pm_subsys_data { struct dev_pm_info { pm_message_t power_state; unsigned int can_wakeup:1; + unsigned int can_oob_wakeup:1; + unsigned int oob_wakeup:1; unsigned int async_suspend:1; bool in_dpm_list:1; /* Owned by the PM core */ bool is_prepared:1; /* Owned by the PM core */ diff --git a/include/linux/pm_wakeup.h b/include/linux/pm_wakeup.h index 4238dde0aaf0..64252cb0f97a 100644 --- a/include/linux/pm_wakeup.h +++ b/include/linux/pm_wakeup.h @@ -83,11 +83,30 @@ static inline bool device_can_wakeup(struct device *dev) return dev->power.can_wakeup; } +static inline bool device_can_oob_wakeup(struct device *dev) +{ + return dev->power.can_oob_wakeup; +} + static inline bool device_may_wakeup(struct device *dev) { return dev->power.can_wakeup && !!dev->power.wakeup; } +static inline bool device_may_oob_wakeup(struct device *dev) +{ + return dev->power.can_oob_wakeup && dev->power.oob_wakeup; +} + +static inline int device_set_oob_wakeup_enable(struct device *dev, bool enable) +{ + if (!dev->power.can_oob_wakeup) + return -EINVAL; + + dev->power.oob_wakeup = enable; + return 0; +} + static inline void device_set_wakeup_path(struct device *dev) { dev->power.wakeup_path = true;