From patchwork Wed Nov 30 03:59:39 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Viresh Kumar X-Patchwork-Id: 84939 Delivered-To: patch@linaro.org Received: by 10.140.20.101 with SMTP id 92csp70306qgi; Tue, 29 Nov 2016 20:00:27 -0800 (PST) X-Received: by 10.98.215.85 with SMTP id v21mr31187594pfl.80.1480478427084; Tue, 29 Nov 2016 20:00:27 -0800 (PST) Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id e132si62557027pfg.66.2016.11.29.20.00.26; Tue, 29 Nov 2016 20:00:27 -0800 (PST) Received-SPF: pass (google.com: best guess record for domain of stable-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; dkim=neutral (body hash did not verify) header.i=@linaro.org; spf=pass (google.com: best guess record for domain of stable-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=stable-owner@vger.kernel.org; dmarc=fail (p=NONE dis=NONE) header.from=linaro.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754515AbcK3EAO (ORCPT + 3 others); Tue, 29 Nov 2016 23:00:14 -0500 Received: from mail-pg0-f41.google.com ([74.125.83.41]:35501 "EHLO mail-pg0-f41.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754367AbcK3EAM (ORCPT ); Tue, 29 Nov 2016 23:00:12 -0500 Received: by mail-pg0-f41.google.com with SMTP id p66so77033343pga.2 for ; Tue, 29 Nov 2016 19:59:49 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id; bh=SPe+euYN383PV4bCeE0yLrV2EwcjT6BQdx2EXDEToPc=; b=jUiCajpXtpb9YErLbKQYOM+lUtAv2VNDOLsd5nHqJJaqaBBHWZpD9xZKBGwefVEKVc brkOkqxnR04yPqXVspUBBBZToqDkZzs92SSocHA7+duheMSo41hMum5fKFoAE8WIXhZA +gI8qBT/vfqS0UqQt0y1Q4gpicFZQwOq/x+sQ= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=SPe+euYN383PV4bCeE0yLrV2EwcjT6BQdx2EXDEToPc=; b=e8CiduxEd/GKSqn4W19feuozyB47fnG+YVbw3NmOtCLI8ijNH9jia+gXSHFSERKR6M LI/rfk5eAYPTEYtECrXoSAb7OtBhqH0HJzUFE70FYvBWr3/JjPYbhyd9GytMj37ykCJv G/Tlj63Zw+V/8h0LQRTn/vT1yVvFjawN0UqfXzOQjoy75beazwRCa+XI6Ii4BSlsHZQl yqiMwwqD/1URBDnEzc0P+1wbCh6ljhLIX2jmXdU8VJtIxa5LBUUtxYdGq1MzXkEBRy/E HE+Q4tts47KUboEPorYLisF5LXghJNGoZ46N8vHz0GLy9P1rMD4aHStwyUNkNB9B+hn+ JkFQ== X-Gm-Message-State: AKaTC01flSRvn4BLxOz/1UoaGlm65AcRQbJcDusFuKAloj8GIXFg0pD5UUcxFwdDBD7gBXfg X-Received: by 10.84.140.133 with SMTP id 5mr67506760plt.76.1480478389055; Tue, 29 Nov 2016 19:59:49 -0800 (PST) Received: from localhost ([122.172.143.30]) by smtp.gmail.com with ESMTPSA id b29sm80577731pgn.48.2016.11.29.19.59.47 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 29 Nov 2016 19:59:48 -0800 (PST) From: Viresh Kumar To: Rafael Wysocki , jy0922.shim@samsung.com, Viresh Kumar , Nishanth Menon , Stephen Boyd Cc: linaro-kernel@lists.linaro.org, linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, Vincent Guittot , "# v4 . 4+" , Viresh Kumar Subject: [PATCH V4] PM / OPP: Pass opp_table to dev_pm_opp_put_regulator() Date: Wed, 30 Nov 2016 09:29:39 +0530 Message-Id: <480ae6e161788d338fb1637aa2615a75588ac3c6.1480478081.git.viresh.kumar@linaro.org> X-Mailer: git-send-email 2.7.1.410.g6faf27b Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Stephen Boyd Joonyoung Shim reported an interesting problem on his ARM octa-core Odoroid-XU3 platform. During system suspend, dev_pm_opp_put_regulator() was failing for a struct device for which dev_pm_opp_set_regulator() is called earlier. This happened because an earlier call to dev_pm_opp_of_cpumask_remove_table() function (from cpufreq-dt.c file) removed all the entries from opp_table->dev_list apart from the last CPU device in the cpumask of CPUs sharing the OPP. But both dev_pm_opp_set_regulator() and dev_pm_opp_put_regulator() routines get CPU device for the first CPU in the cpumask. And so the OPP core failed to find the OPP table for the struct device. In order to fix that up properly, we need to revisit APIs like dev_pm_opp_set_regulator() and make them talk in terms of cookies provided by the OPP core. But such a solution will be hard to backport to stable kernels. This patch attempts to fix this problem by returning a pointer to the opp_table from dev_pm_opp_set_regulator() and using that as the parameter to dev_pm_opp_put_regulator(). This ensures that the dev_pm_opp_put_regulator() doesn't fail to find the opp table. Note that similar design problem also exists with other dev_pm_opp_put_*() APIs, but those aren't used currently by anyone and so we don't need to update them for now. [Viresh]: Written commit log, minor improvements in the patch and tested on exynos 5250. Cc: # v4.4+ Reported-by: Joonyoung Shim Signed-off-by: Stephen Boyd Signed-off-by: Viresh Kumar --- V3->V4: - Completely different approach, suggested earlier by Stephen. - Can be merged safely now as both /me and Stephen agree to this one. @Joonyoung: Can you please test this last patch please ? drivers/base/power/opp/core.c | 37 +++++++++++++------------------------ drivers/cpufreq/cpufreq-dt.c | 12 ++++++++---- include/linux/pm_opp.h | 11 ++++++----- 3 files changed, 27 insertions(+), 33 deletions(-) -- 2.7.1.410.g6faf27b -- To unsubscribe from this list: send the line "unsubscribe stable" 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/opp/core.c b/drivers/base/power/opp/core.c index 4c7c6da7a989..de27562d9ced 100644 --- a/drivers/base/power/opp/core.c +++ b/drivers/base/power/opp/core.c @@ -1316,58 +1316,57 @@ EXPORT_SYMBOL_GPL(dev_pm_opp_put_prop_name); * that this function is *NOT* called under RCU protection or in contexts where * mutex cannot be locked. */ -int dev_pm_opp_set_regulator(struct device *dev, const char *name) +struct opp_table *dev_pm_opp_set_regulator(struct device *dev, const char *name) { struct opp_table *opp_table; struct regulator *reg; - int ret; mutex_lock(&opp_table_lock); opp_table = _add_opp_table(dev); if (!opp_table) { - ret = -ENOMEM; + opp_table = ERR_PTR(-ENOMEM); goto unlock; } /* This should be called before OPPs are initialized */ if (WARN_ON(!list_empty(&opp_table->opp_list))) { - ret = -EBUSY; + opp_table = ERR_PTR(-EBUSY); goto err; } /* Already have a regulator set */ if (WARN_ON(!IS_ERR(opp_table->regulator))) { - ret = -EBUSY; + opp_table = ERR_PTR(-EBUSY); goto err; } /* Allocate the regulator */ reg = regulator_get_optional(dev, name); if (IS_ERR(reg)) { - ret = PTR_ERR(reg); - if (ret != -EPROBE_DEFER) - dev_err(dev, "%s: no regulator (%s) found: %d\n", - __func__, name, ret); + opp_table = (struct opp_table *)reg; + if (PTR_ERR(reg) != -EPROBE_DEFER) + dev_err(dev, "%s: no regulator (%s) found: %ld\n", + __func__, name, PTR_ERR(reg)); goto err; } opp_table->regulator = reg; mutex_unlock(&opp_table_lock); - return 0; + return opp_table; err: _remove_opp_table(opp_table); unlock: mutex_unlock(&opp_table_lock); - return ret; + return opp_table; } EXPORT_SYMBOL_GPL(dev_pm_opp_set_regulator); /** * dev_pm_opp_put_regulator() - Releases resources blocked for regulator - * @dev: Device for which regulator was set. + * @opp_table: opp_table returned from dev_pm_opp_set_regulator * * Locking: The internal opp_table and opp structures are RCU protected. * Hence this function internally uses RCU updater strategy with mutex locks @@ -1375,22 +1374,12 @@ EXPORT_SYMBOL_GPL(dev_pm_opp_set_regulator); * that this function is *NOT* called under RCU protection or in contexts where * mutex cannot be locked. */ -void dev_pm_opp_put_regulator(struct device *dev) +void dev_pm_opp_put_regulator(struct opp_table *opp_table) { - struct opp_table *opp_table; - mutex_lock(&opp_table_lock); - /* Check for existing table for 'dev' first */ - opp_table = _find_opp_table(dev); - if (IS_ERR(opp_table)) { - dev_err(dev, "Failed to find opp_table: %ld\n", - PTR_ERR(opp_table)); - goto unlock; - } - if (IS_ERR(opp_table->regulator)) { - dev_err(dev, "%s: Doesn't have regulator set\n", __func__); + pr_err("%s: Doesn't have regulator set\n", __func__); goto unlock; } diff --git a/drivers/cpufreq/cpufreq-dt.c b/drivers/cpufreq/cpufreq-dt.c index 5c07ae05d69a..4d3ec92cbabf 100644 --- a/drivers/cpufreq/cpufreq-dt.c +++ b/drivers/cpufreq/cpufreq-dt.c @@ -28,6 +28,7 @@ #include "cpufreq-dt.h" struct private_data { + struct opp_table *opp_table; struct device *cpu_dev; struct thermal_cooling_device *cdev; const char *reg_name; @@ -143,6 +144,7 @@ static int resources_available(void) static int cpufreq_init(struct cpufreq_policy *policy) { struct cpufreq_frequency_table *freq_table; + struct opp_table *opp_table = NULL; struct private_data *priv; struct device *cpu_dev; struct clk *cpu_clk; @@ -186,8 +188,9 @@ static int cpufreq_init(struct cpufreq_policy *policy) */ name = find_supply_name(cpu_dev); if (name) { - ret = dev_pm_opp_set_regulator(cpu_dev, name); - if (ret) { + opp_table = dev_pm_opp_set_regulator(cpu_dev, name); + if (IS_ERR(opp_table)) { + ret = PTR_ERR(opp_table); dev_err(cpu_dev, "Failed to set regulator for cpu%d: %d\n", policy->cpu, ret); goto out_put_clk; @@ -237,6 +240,7 @@ static int cpufreq_init(struct cpufreq_policy *policy) } priv->reg_name = name; + priv->opp_table = opp_table; ret = dev_pm_opp_init_cpufreq_table(cpu_dev, &freq_table); if (ret) { @@ -285,7 +289,7 @@ static int cpufreq_init(struct cpufreq_policy *policy) out_free_opp: dev_pm_opp_of_cpumask_remove_table(policy->cpus); if (name) - dev_pm_opp_put_regulator(cpu_dev); + dev_pm_opp_put_regulator(opp_table); out_put_clk: clk_put(cpu_clk); @@ -300,7 +304,7 @@ static int cpufreq_exit(struct cpufreq_policy *policy) dev_pm_opp_free_cpufreq_table(priv->cpu_dev, &policy->freq_table); dev_pm_opp_of_cpumask_remove_table(policy->related_cpus); if (priv->reg_name) - dev_pm_opp_put_regulator(priv->cpu_dev); + dev_pm_opp_put_regulator(priv->opp_table); clk_put(policy->clk); kfree(priv); diff --git a/include/linux/pm_opp.h b/include/linux/pm_opp.h index bca26157f5b6..f6bc76501912 100644 --- a/include/linux/pm_opp.h +++ b/include/linux/pm_opp.h @@ -19,6 +19,7 @@ struct dev_pm_opp; struct device; +struct opp_table; enum dev_pm_opp_event { OPP_EVENT_ADD, OPP_EVENT_REMOVE, OPP_EVENT_ENABLE, OPP_EVENT_DISABLE, @@ -62,8 +63,8 @@ int dev_pm_opp_set_supported_hw(struct device *dev, const u32 *versions, void dev_pm_opp_put_supported_hw(struct device *dev); int dev_pm_opp_set_prop_name(struct device *dev, const char *name); void dev_pm_opp_put_prop_name(struct device *dev); -int dev_pm_opp_set_regulator(struct device *dev, const char *name); -void dev_pm_opp_put_regulator(struct device *dev); +struct opp_table *dev_pm_opp_set_regulator(struct device *dev, const char *name); +void dev_pm_opp_put_regulator(struct opp_table *opp_table); int dev_pm_opp_set_rate(struct device *dev, unsigned long target_freq); int dev_pm_opp_set_sharing_cpus(struct device *cpu_dev, const struct cpumask *cpumask); int dev_pm_opp_get_sharing_cpus(struct device *cpu_dev, struct cpumask *cpumask); @@ -170,12 +171,12 @@ static inline int dev_pm_opp_set_prop_name(struct device *dev, const char *name) static inline void dev_pm_opp_put_prop_name(struct device *dev) {} -static inline int dev_pm_opp_set_regulator(struct device *dev, const char *name) +static inline struct opp_table *dev_pm_opp_set_regulator(struct device *dev, const char *name) { - return -ENOTSUPP; + return ERR_PTR(-ENOTSUPP); } -static inline void dev_pm_opp_put_regulator(struct device *dev) {} +static inline void dev_pm_opp_put_regulator(struct opp_table *opp_table) {} static inline int dev_pm_opp_set_rate(struct device *dev, unsigned long target_freq) {