From patchwork Wed Nov 23 13:51:24 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tobias Jakobi X-Patchwork-Id: 9443349 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 88AF760779 for ; Wed, 23 Nov 2016 14:00:50 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 762C1262FF for ; Wed, 23 Nov 2016 14:00:50 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 6B31926490; Wed, 23 Nov 2016 14:00:50 +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 190FF26419 for ; Wed, 23 Nov 2016 14:00:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935005AbcKWOAt (ORCPT ); Wed, 23 Nov 2016 09:00:49 -0500 Received: from smtp.math.uni-bielefeld.de ([129.70.45.10]:58273 "EHLO smtp.math.uni-bielefeld.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756575AbcKWOAr (ORCPT ); Wed, 23 Nov 2016 09:00:47 -0500 Received: from chidori.dhcp.uni-bielefeld.de (dhcp-10-68-170-113.dhcp.uni-bielefeld.de [10.68.170.113]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA256 (128/128 bits)) (Client did not present a certificate) by smtp.math.uni-bielefeld.de (Postfix) with ESMTPSA id 452D15FA4B; Wed, 23 Nov 2016 14:51:54 +0100 (CET) From: Tobias Jakobi To: linux-samsung-soc@vger.kernel.org Cc: linux-pm@vger.kernel.org, m.reichl@fivetechno.de, myungjoo.ham@gmail.com, cw00.choi@samsung.com, Tobias Jakobi Subject: [RFC 1/4] PM / devfreq: Add DevFreq subsystem suspend/resume Date: Wed, 23 Nov 2016 14:51:24 +0100 Message-Id: <1479909087-22659-2-git-send-email-tjakobi@math.uni-bielefeld.de> X-Mailer: git-send-email 2.7.3 In-Reply-To: <1479909087-22659-1-git-send-email-tjakobi@math.uni-bielefeld.de> References: <1479909087-22659-1-git-send-email-tjakobi@math.uni-bielefeld.de> 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 This suspend/resume operations works analogous to the cpufreq_{suspend,resume}() calls in the CPUFreq subsystem. Signed-off-by: Tobias Jakobi --- drivers/devfreq/devfreq.c | 75 +++++++++++++++++++++++++++++++++++++++++++++++ include/linux/devfreq.h | 10 +++++++ 2 files changed, 85 insertions(+) diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c index bf3ea76..2f1aa83 100644 --- a/drivers/devfreq/devfreq.c +++ b/drivers/devfreq/devfreq.c @@ -785,6 +785,81 @@ int devfreq_resume_device(struct devfreq *devfreq) EXPORT_SYMBOL(devfreq_resume_device); /** + * devfreq_suspend() - Suspend DevFreq governors + * + * Called during system wide Suspend/Hibernate cycles for suspending governors + * in the same fashion as cpufreq_suspend(). + */ +void devfreq_suspend(void) +{ + struct devfreq *devfreq; + unsigned long freq; + int ret; + + mutex_lock(&devfreq_list_lock); + + list_for_each_entry(devfreq, &devfreq_list, node) { + if (!devfreq->suspend_freq) + continue; + + ret = devfreq_suspend_device(devfreq); + if (ret < 0) { + dev_warn(&devfreq->dev, "%s: governor suspend failed\n", __func__); + continue; + } + + devfreq->resume_freq = 0; + if (devfreq->profile->get_cur_freq) { + ret = devfreq->profile->get_cur_freq(devfreq->dev.parent, &freq); + if (ret >= 0) + devfreq->resume_freq = freq; + } + + freq = devfreq->suspend_freq; + ret = devfreq->profile->target(devfreq->dev.parent, &freq, 0); + + if (ret < 0) + dev_warn(&devfreq->dev, "%s: setting suspend frequency failed\n", __func__); + } + + mutex_unlock(&devfreq_list_lock); +} + +/** + * devfreq_resume() - Resume DevFreq governors + * + * Called during system wide Suspend/Hibernate cycle for resuming governors that + * are suspended with devfreq_suspend(). + */ +void devfreq_resume(void) +{ + struct devfreq *devfreq; + unsigned long freq; + int ret; + + mutex_lock(&devfreq_list_lock); + + list_for_each_entry(devfreq, &devfreq_list, node) { + if (!devfreq->suspend_freq) + continue; + + freq = devfreq->resume_freq; + ret = devfreq->profile->target(devfreq->dev.parent, &freq, 0); + + if (ret < 0) { + dev_warn(&devfreq->dev, "%s: setting resume frequency failed\n", __func__); + continue; + } + + ret = devfreq_resume_device(devfreq); + if (ret < 0) + dev_warn(&devfreq->dev, "%s: governor resume failed\n", __func__); + } + + mutex_unlock(&devfreq_list_lock); +} + +/** * devfreq_add_governor() - Add devfreq governor * @governor: the devfreq governor to be added */ diff --git a/include/linux/devfreq.h b/include/linux/devfreq.h index 2de4e2e..555d024 100644 --- a/include/linux/devfreq.h +++ b/include/linux/devfreq.h @@ -171,6 +171,9 @@ struct devfreq { struct notifier_block nb; struct delayed_work work; + unsigned long suspend_freq; /* freq during devfreq suspend */ + unsigned long resume_freq; /* freq restored after suspend cycle */ + unsigned long previous_freq; struct devfreq_dev_status last_status; @@ -211,6 +214,10 @@ extern void devm_devfreq_remove_device(struct device *dev, extern int devfreq_suspend_device(struct devfreq *devfreq); extern int devfreq_resume_device(struct devfreq *devfreq); +/* Suspend/resume the entire Devfreq subsystem. */ +void devfreq_suspend(void); +void devfreq_resume(void); + /* Helper functions for devfreq user device driver with OPP. */ extern struct dev_pm_opp *devfreq_recommended_opp(struct device *dev, unsigned long *freq, u32 flags); @@ -410,6 +417,9 @@ static inline int devfreq_update_stats(struct devfreq *df) { return -EINVAL; } + +static inline void devfreq_suspend(void) {} +static inline void devfreq_resume(void) {} #endif /* CONFIG_PM_DEVFREQ */ #endif /* __LINUX_DEVFREQ_H__ */