From mboxrd@z Thu Jan 1 00:00:00 1970 From: Viresh Kumar Subject: [PATCH 3/7] cpufreq: Introduce ->usable() callback for cpufreq drivers Date: Wed, 26 Nov 2014 11:22:58 +0530 Message-ID: <95b84bb8af3d4d9667a79db520cfa37d9444d75b.1416980448.git.viresh.kumar@linaro.org> References: Return-path: Received: from mail-pd0-f171.google.com ([209.85.192.171]:37949 "EHLO mail-pd0-f171.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752211AbaKZFxa (ORCPT ); Wed, 26 Nov 2014 00:53:30 -0500 Received: by mail-pd0-f171.google.com with SMTP id y13so2111487pdi.16 for ; Tue, 25 Nov 2014 21:53:29 -0800 (PST) In-Reply-To: In-Reply-To: References: Sender: linux-pm-owner@vger.kernel.org List-Id: linux-pm@vger.kernel.org To: Rafael Wysocki , edubezval@gmail.com Cc: linaro-kernel@lists.linaro.org, linux-pm@vger.kernel.org, l.majewski@samsung.com, Viresh Kumar Currently there is no callback for cpufreq drivers which is called once the policy is ready to be used. There are some requirements where such a callback is required. One of them is registering a cooling device with the help of of_cpufreq_cooling_register(). This routine tries to get 'struct cpufreq_policy' for CPUs which isn't yet initialed at the time ->init() is called and so we face issues while registering the cooling device. Because we can't register cooling device from ->init(), we need a callback that is called after the policy is ready to be used and hence we introduce ->usable() callback. Signed-off-by: Viresh Kumar --- drivers/cpufreq/cpufreq.c | 5 +++++ include/linux/cpufreq.h | 4 ++++ 2 files changed, 9 insertions(+) diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c index de2c3e1..4fb95b9 100644 --- a/drivers/cpufreq/cpufreq.c +++ b/drivers/cpufreq/cpufreq.c @@ -1285,8 +1285,13 @@ static int __cpufreq_add_dev(struct device *dev, struct subsys_interface *sif) up_write(&policy->rwsem); kobject_uevent(&policy->kobj, KOBJ_ADD); + up_read(&cpufreq_rwsem); + /* Callback for handling stuff after policy is ready */ + if (cpufreq_driver->usable) + cpufreq_driver->usable(policy); + pr_debug("initialization complete\n"); return 0; diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h index db3c130..4795c0b 100644 --- a/include/linux/cpufreq.h +++ b/include/linux/cpufreq.h @@ -267,6 +267,10 @@ struct cpufreq_driver { void (*stop_cpu)(struct cpufreq_policy *policy); int (*suspend)(struct cpufreq_policy *policy); int (*resume)(struct cpufreq_policy *policy); + + /* Will be called after the driver is fully initialized */ + void (*usable)(struct cpufreq_policy *policy); + struct freq_attr **attr; /* platform specific boost support code */ -- 2.0.3.693.g996b0fd