From mboxrd@z Thu Jan 1 00:00:00 1970 From: Lukasz Majewski Subject: Re: [PATCH V2 4/4] cpufreq-dt: register cooling device from ->ready() callback Date: Thu, 27 Nov 2014 12:08:15 +0100 Message-ID: <20141127120815.019cd529@amdc2363> References: <9ea95c03d129b45140948d94cc4ebcf1bcbbac44.1417048449.git.viresh.kumar@linaro.org> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Return-path: Received: from mailout1.samsung.com ([203.254.224.24]:16372 "EHLO mailout1.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752471AbaK0LIV (ORCPT ); Thu, 27 Nov 2014 06:08:21 -0500 Received: from epcpsbgm2.samsung.com (epcpsbgm2 [203.254.230.27]) by mailout1.samsung.com (Oracle Communications Messaging Server 7u4-24.01(7.0.4.24.0) 64bit (built Nov 17 2011)) with ESMTP id <0NFP004NY2XWZQ30@mailout1.samsung.com> for linux-pm@vger.kernel.org; Thu, 27 Nov 2014 20:08:20 +0900 (KST) In-reply-to: <9ea95c03d129b45140948d94cc4ebcf1bcbbac44.1417048449.git.viresh.kumar@linaro.org> Sender: linux-pm-owner@vger.kernel.org List-Id: linux-pm@vger.kernel.org To: Viresh Kumar Cc: Rafael Wysocki , "edubezval@gmail.com" , "linaro-kernel@lists.linaro.org" , "linux-pm@vger.kernel.org" Hi Viresh, > Currently we are calling of_cpufreq_cooling_register() from ->init() > callback. At this point of time cpufreq driver's policy isn't > completely ready to be used as few of its fields/structure/pointers > aren't yet initialized. > > Because of_cpufreq_cooling_register() tries to access policy with > help of cpufreq_cpu_get() and then tries to get freq-table as well, > these calls fail. > > To fix this, register the cooling device after the policy is ready to > be used. And the right callback for it is the newly added ->ready() > one. > > Signed-off-by: Viresh Kumar > Reviewed-by: Eduardo Valentin > Tested-by: Eduardo Valentin > --- > drivers/cpufreq/cpufreq-dt.c | 51 > +++++++++++++++++++++++++++----------------- 1 file changed, 32 > insertions(+), 19 deletions(-) > > diff --git a/drivers/cpufreq/cpufreq-dt.c > b/drivers/cpufreq/cpufreq-dt.c index 7374fc4..e720954 100644 > --- a/drivers/cpufreq/cpufreq-dt.c > +++ b/drivers/cpufreq/cpufreq-dt.c > @@ -186,7 +186,6 @@ static int cpufreq_init(struct cpufreq_policy > *policy) { > struct cpufreq_dt_platform_data *pd; > struct cpufreq_frequency_table *freq_table; > - struct thermal_cooling_device *cdev; > struct device_node *np; > struct private_data *priv; > struct device *cpu_dev; > @@ -269,20 +268,6 @@ static int cpufreq_init(struct cpufreq_policy > *policy) goto out_free_priv; > } > > - /* > - * For now, just loading the cooling device; > - * thermal DT code takes care of matching them. > - */ > - if (of_find_property(np, "#cooling-cells", NULL)) { > - cdev = of_cpufreq_cooling_register(np, > policy->related_cpus); > - if (IS_ERR(cdev)) > - dev_err(cpu_dev, > - "running cpufreq without cooling > device: %ld\n", > - PTR_ERR(cdev)); > - else > - priv->cdev = cdev; > - } > - > priv->cpu_dev = cpu_dev; > priv->cpu_reg = cpu_reg; > policy->driver_data = priv; > @@ -292,7 +277,7 @@ static int cpufreq_init(struct cpufreq_policy > *policy) if (ret) { > dev_err(cpu_dev, "%s: invalid frequency table: > %d\n", __func__, ret); > - goto out_cooling_unregister; > + goto out_free_cpufreq_table; > } > > policy->cpuinfo.transition_latency = transition_latency; > @@ -305,8 +290,7 @@ static int cpufreq_init(struct cpufreq_policy > *policy) > return 0; > > -out_cooling_unregister: > - cpufreq_cooling_unregister(priv->cdev); > +out_free_cpufreq_table: > dev_pm_opp_free_cpufreq_table(cpu_dev, &freq_table); > out_free_priv: > kfree(priv); > @@ -324,7 +308,8 @@ static int cpufreq_exit(struct cpufreq_policy > *policy) { > struct private_data *priv = policy->driver_data; > > - cpufreq_cooling_unregister(priv->cdev); > + if (priv->cdev) > + cpufreq_cooling_unregister(priv->cdev); > dev_pm_opp_free_cpufreq_table(priv->cpu_dev, > &policy->freq_table); clk_put(policy->clk); > if (!IS_ERR(priv->cpu_reg)) > @@ -334,6 +319,33 @@ static int cpufreq_exit(struct cpufreq_policy > *policy) return 0; > } > > +static void cpufreq_ready(struct cpufreq_policy *policy) > +{ > + struct private_data *priv = policy->driver_data; > + struct device_node *np = of_node_get(priv->cpu_dev->of_node); > + > + if (WARN_ON(!np)) > + return; > + > + /* > + * For now, just loading the cooling device; > + * thermal DT code takes care of matching them. > + */ > + if (of_find_property(np, "#cooling-cells", NULL)) { > + priv->cdev = of_cpufreq_cooling_register(np, > + > policy->related_cpus); > + if (IS_ERR(priv->cdev)) { > + dev_err(priv->cpu_dev, > + "running cpufreq without cooling > device: %ld\n", > + PTR_ERR(priv->cdev)); > + > + priv->cdev = NULL; > + } > + } > + > + of_node_put(np); > +} > + > static struct cpufreq_driver dt_cpufreq_driver = { > .flags = CPUFREQ_STICKY | CPUFREQ_NEED_INITIAL_FREQ_CHECK, > .verify = cpufreq_generic_frequency_table_verify, > @@ -341,6 +353,7 @@ static struct cpufreq_driver dt_cpufreq_driver = { > .get = cpufreq_generic_get, > .init = cpufreq_init, > .exit = cpufreq_exit, > + .ready = cpufreq_ready, > .name = "cpufreq-dt", > .attr = cpufreq_generic_attr, > }; Reviewed-by: Lukasz Majewski -- Best regards, Lukasz Majewski Samsung R&D Institute Poland (SRPOL) | Linux Platform Group