Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753827Ab2B0Ecp (ORCPT ); Sun, 26 Feb 2012 23:32:45 -0500 Received: from mail-lpp01m010-f46.google.com ([209.85.215.46]:56382 "EHLO mail-lpp01m010-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753322Ab2B0Ecn convert rfc822-to-8bit (ORCPT ); Sun, 26 Feb 2012 23:32:43 -0500 Authentication-Results: mr.google.com; spf=pass (google.com: domain of amit.kachhap@linaro.org designates 10.152.113.136 as permitted sender) smtp.mail=amit.kachhap@linaro.org MIME-Version: 1.0 In-Reply-To: <4D68720C2E767A4AA6A8796D42C8EB590442F2@BGSMSX101.gar.corp.intel.com> References: <1329905650-30161-1-git-send-email-amit.kachhap@linaro.org> <1329905650-30161-3-git-send-email-amit.kachhap@linaro.org> <4D68720C2E767A4AA6A8796D42C8EB590442F2@BGSMSX101.gar.corp.intel.com> Date: Mon, 27 Feb 2012 10:02:41 +0530 Message-ID: Subject: Re: [PATCH 2/4] thermal: Add generic cpufreq cooling implementation From: Amit Kachhap To: "R, Durgadoss" Cc: "linux-pm@lists.linux-foundation.org" , "linux-kernel@vger.kernel.org" , "mjg59@srcf.ucam.org" , "linux-acpi@vger.kernel.org" , "lenb@kernel.org" , "linaro-dev@lists.linaro.org" , "rob.lee@linaro.org" , "patches@linaro.org" Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 21063 Lines: 591 Hi Durgadoss, Thanks for the detailed review comments. On 24 February 2012 16:34, R, Durgadoss wrote: > Hi Amit, > >> -----Original Message----- >> From: amit kachhap [mailto:amitdanielk@gmail.com] On Behalf Of Amit Daniel >> Kachhap >> Sent: Wednesday, February 22, 2012 3:44 PM >> To: linux-pm@lists.linux-foundation.org >> Cc: linux-kernel@vger.kernel.org; mjg59@srcf.ucam.org; linux- >> acpi@vger.kernel.org; lenb@kernel.org; linaro-dev@lists.linaro.org; >> amit.kachhap@linaro.org; R, Durgadoss; rob.lee@linaro.org; patches@linaro.org >> Subject: [PATCH 2/4] thermal: Add generic cpufreq cooling implementation >> >> This patch adds support for generic cpu thermal cooling low level >> implementations using frequency scaling up/down based on the request >> from user. Different cpu related cooling devices can be registered by the > > I believe what you mean by 'user' is another Driver using this code.. right ?? Yes. > >> user and the binding of these cooling devices to the corresponding >> trip points can be easily done as the registration API's return the >> cooling device pointer. The user of these api's are responsible for >> passing clipping frequency in percentages. >> >> Signed-off-by: Amit Daniel Kachhap >> --- >> ?Documentation/thermal/cpu-cooling-api.txt | ? 40 ++++ >> ?drivers/thermal/Kconfig ? ? ? ? ? ? ? ? ? | ? 11 + >> ?drivers/thermal/Makefile ? ? ? ? ? ? ? ? ?| ? ?1 + >> ?drivers/thermal/cpu_cooling.c ? ? ? ? ? ? | ?310 +++++++++++++++++++++++++++++ >> ?include/linux/cpu_cooling.h ? ? ? ? ? ? ? | ? 54 +++++ >> ?5 files changed, 416 insertions(+), 0 deletions(-) >> ?create mode 100644 Documentation/thermal/cpu-cooling-api.txt >> ?create mode 100644 drivers/thermal/cpu_cooling.c >> ?create mode 100644 include/linux/cpu_cooling.h >> >> diff --git a/Documentation/thermal/cpu-cooling-api.txt >> b/Documentation/thermal/cpu-cooling-api.txt >> new file mode 100644 >> index 0000000..04de67c >> --- /dev/null >> +++ b/Documentation/thermal/cpu-cooling-api.txt >> @@ -0,0 +1,40 @@ >> +CPU cooling api's How To >> +=================================== >> + >> +Written by Amit Daniel Kachhap >> + >> +Updated: 13 Dec 2011 >> + >> +Copyright (c) ?2011 Samsung Electronics Co., Ltd(http://www.samsung.com) >> + >> +0. Introduction >> + >> +The generic cpu cooling(freq clipping, cpuhotplug) provides >> +registration/unregistration api's to the user. The binding of the cooling >> +devices to the trip point is left for the user. The registration api's returns >> +the cooling device pointer. >> + >> +1. cpufreq cooling api's >> + >> +1.1 cpufreq registration api's >> +1.1.1 struct thermal_cooling_device *cpufreq_cooling_register( >> + ? ? struct freq_pctg_table *tab_ptr, unsigned int tab_size, >> + ? ? const struct cpumask *mask_val) >> + >> + ? ?This interface function registers the cpufreq cooling device with the name >> + ? ?"thermal-cpufreq-%x". This api can support multiple instance of cpufreq >> cooling >> + ? ?devices. >> + >> + ? ?tab_ptr: The table containing the percentage of frequency to be clipped >> for >> + ? ?each cooling state. >> + ? ? .freq_clip_pctg: Percentage of frequency to be clipped for each allowed >> + ? ? ?cpus. >> + ? ? .polling_interval: polling interval for this cooling state. >> + ? ?tab_size: the total number of cooling state. > > Although I can understand that the table size is equal to > the total number of cooling states, it is better to name it 'num_cooling_states' > (or something) that means what it is.. Yes your idea makes more sense. Will accept it in the next version. > >> + ? ?mask_val: all the allowed cpu's where frequency clipping can happen. >> + >> +1.1.2 void cpufreq_cooling_unregister(struct thermal_cooling_device *cdev) >> + >> + ? ?This interface function unregisters the "thermal-cpufreq-%x" cooling >> device. >> + >> + ? ?cdev: Cooling device pointer which has to be unregistered. >> diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig >> index f7f71b2..298c1cd 100644 >> --- a/drivers/thermal/Kconfig >> +++ b/drivers/thermal/Kconfig >> @@ -18,3 +18,14 @@ config THERMAL_HWMON >> ? ? ? depends on THERMAL >> ? ? ? depends on HWMON=y || HWMON=THERMAL >> ? ? ? default y >> + >> +config CPU_THERMAL >> + ? ? bool "generic cpu cooling support" >> + ? ? depends on THERMAL >> + ? ? help >> + ? ? ? This implements the generic cpu cooling mechanism through frequency >> + ? ? ? reduction, cpu hotplug and any other ways of reducing temperature. An >> + ? ? ? ACPI version of this already exists(drivers/acpi/processor_thermal.c). >> + ? ? ? This will be useful for platforms using the generic thermal interface >> + ? ? ? and not the ACPI interface. >> + ? ? ? If you want this support, you should say Y or M here. >> diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile >> index 31108a0..655cbc4 100644 >> --- a/drivers/thermal/Makefile >> +++ b/drivers/thermal/Makefile >> @@ -3,3 +3,4 @@ >> ?# >> >> ?obj-$(CONFIG_THERMAL) ? ? ? ? ? ? ? ?+= thermal_sys.o >> +obj-$(CONFIG_CPU_THERMAL) ? ?+= cpu_cooling.o >> diff --git a/drivers/thermal/cpu_cooling.c b/drivers/thermal/cpu_cooling.c >> new file mode 100644 >> index 0000000..298f550 >> --- /dev/null >> +++ b/drivers/thermal/cpu_cooling.c >> @@ -0,0 +1,310 @@ >> +/* >> + * ?linux/drivers/thermal/cpu_cooling.c >> + * >> + * ?Copyright (C) 2011 ? ? ? Samsung Electronics Co., Ltd(http://www.samsung.com) >> + * ?Copyright (C) 2011 ?Amit Daniel >> + * >> + * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ >> + * ?This program is free software; you can redistribute it and/or modify >> + * ?it under the terms of the GNU General Public License as published by >> + * ?the Free Software Foundation; version 2 of the License. >> + * >> + * ?This program is distributed in the hope that it will be useful, but >> + * ?WITHOUT ANY WARRANTY; without even the implied warranty of >> + * ?MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. ?See the GNU >> + * ?General Public License for more details. >> + * >> + * ?You should have received a copy of the GNU General Public License along >> + * ?with this program; if not, write to the Free Software Foundation, Inc., >> + * ?59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. >> + * >> + * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ >> + */ >> +#include >> +#include >> +#include >> +#include >> +#include >> +#include >> +#include >> +#include >> +#include >> + >> +#ifdef CONFIG_CPU_FREQ > > Except the _idr methods, all the code is inside this #ifdef. > So, I think it is better to add this dependency in Kconfig, > and leave this code clean w/o many #ifdef's. ok > >> +struct cpufreq_cooling_device { >> + ? ? int id; >> + ? ? struct thermal_cooling_device *cool_dev; >> + ? ? struct freq_pctg_table *tab_ptr; >> + ? ? unsigned int tab_size; >> + ? ? unsigned int cpufreq_state; >> + ? ? const struct cpumask *allowed_cpus; >> + ? ? struct list_head node; >> +}; >> + >> +static LIST_HEAD(cooling_cpufreq_list); >> +static DEFINE_MUTEX(cooling_cpufreq_lock); >> +static DEFINE_IDR(cpufreq_idr); >> +static struct cpufreq_cooling_device *notify_cpufreq; > > Please move this after the DEFINE_PER_CPU. > Hard to notice here.. ok > >> +static DEFINE_PER_CPU(unsigned int, max_policy_freq); >> +#endif /*CONFIG_CPU_FREQ*/ >> + >> +static int get_idr(struct idr *idr, struct mutex *lock, int *id) >> +{ >> + ? ? int err; >> +again: >> + ? ? if (unlikely(idr_pre_get(idr, GFP_KERNEL) == 0)) >> + ? ? ? ? ? ? return -ENOMEM; >> + >> + ? ? if (lock) >> + ? ? ? ? ? ? mutex_lock(lock); >> + ? ? err = idr_get_new(idr, NULL, id); >> + ? ? if (lock) >> + ? ? ? ? ? ? mutex_unlock(lock); >> + ? ? if (unlikely(err == -EAGAIN)) >> + ? ? ? ? ? ? goto again; >> + ? ? else if (unlikely(err)) >> + ? ? ? ? ? ? return err; >> + >> + ? ? *id = *id & MAX_ID_MASK; >> + ? ? return 0; >> +} >> + >> +static void release_idr(struct idr *idr, struct mutex *lock, int id) >> +{ >> + ? ? if (lock) >> + ? ? ? ? ? ? mutex_lock(lock); >> + ? ? idr_remove(idr, id); >> + ? ? if (lock) >> + ? ? ? ? ? ? mutex_unlock(lock); >> +} >> + >> +#ifdef CONFIG_CPU_FREQ >> +/*Below codes defines functions to be used for cpufreq as cooling device*/ >> +static bool is_cpufreq_valid(int cpu) >> +{ >> + ? ? struct cpufreq_policy policy; >> + ? ? if (!cpufreq_get_policy(&policy, cpu)) >> + ? ? ? ? ? ? return true; >> + ? ? return false; > > Why not just do a return !cpufreq_get_policy(&policy, cpu); ok > >> +} >> + >> +static int cpufreq_apply_cooling(struct cpufreq_cooling_device >> *cpufreq_device, >> + ? ? ? ? ? ? ? ? ? ? ? ? ? ? unsigned long cooling_state) >> +{ >> + ? ? int cpuid, this_cpu = smp_processor_id(); >> + >> + ? ? if (!is_cpufreq_valid(this_cpu)) > > You are not using this_cpu anywhere else..so, directly use > Smp_processor_id() here.. > Ok agreed. >> + ? ? ? ? ? ? return 0; >> + >> + ? ? if (cooling_state > cpufreq_device->tab_size) >> + ? ? ? ? ? ? return -EINVAL; >> + >> + ? ? /*Check if last cooling level is same as current cooling level*/ > > Use either 'state' or 'level' in comments as well as the variable name > Makes it easy to read.. Ok, will use state. > >> + ? ? if (cpufreq_device->cpufreq_state == cooling_state) >> + ? ? ? ? ? ? return 0; >> + >> + ? ? cpufreq_device->cpufreq_state = cooling_state; >> + >> + ? ? /*cpufreq thermal notifier uses this cpufreq device pointer*/ >> + ? ? notify_cpufreq = cpufreq_device; >> + >> + ? ? for_each_cpu(cpuid, cpufreq_device->allowed_cpus) { >> + ? ? ? ? ? ? if (is_cpufreq_valid(cpuid)) >> + ? ? ? ? ? ? ? ? ? ? cpufreq_update_policy(cpuid); >> + ? ? } >> + >> + ? ? return 0; >> +} >> + >> +static int thermal_cpufreq_notifier(struct notifier_block *nb, >> + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? unsigned long event, void *data) >> +{ >> + ? ? struct cpufreq_policy *policy = data; >> + ? ? struct freq_pctg_table *th_table; >> + ? ? unsigned long max_freq = 0; >> + ? ? unsigned int th_pctg = 0, level; >> + >> + ? ? if (event != CPUFREQ_ADJUST) >> + ? ? ? ? ? ? return 0; >> + >> + ? ? if (!notify_cpufreq) >> + ? ? ? ? ? ? return 0; > > Why not combine both if's with an || ? Ok > >> + >> + ? ? level = notify_cpufreq->cpufreq_state; > > Yes..here it is..please use level/state.. Ok, will use state > >> + >> + ? ? if (level > 0) { >> + ? ? ? ? ? ? th_table = >> + ? ? ? ? ? ? ? ? ? ? &(notify_cpufreq->tab_ptr[level - 1]); >> + ? ? ? ? ? ? th_pctg = th_table->freq_clip_pctg; >> + ? ? ? ? ? ? max_freq = >> + ? ? ? ? ? ? (policy->cpuinfo.max_freq * (100 - th_pctg)) / 100; >> + >> + ? ? ? ? ? ? if (per_cpu(max_policy_freq, policy->cpu) == 0) >> + ? ? ? ? ? ? ? ? ? ? per_cpu(max_policy_freq, policy->cpu) = policy->max; >> + ? ? } else { >> + ? ? ? ? ? ? if (per_cpu(max_policy_freq, policy->cpu) != 0) { >> + ? ? ? ? ? ? ? ? ? ? max_freq = per_cpu(max_policy_freq, policy->cpu); >> + ? ? ? ? ? ? ? ? ? ? per_cpu(max_policy_freq, policy->cpu) = 0; >> + ? ? ? ? ? ? } else { >> + ? ? ? ? ? ? ? ? ? ? max_freq = policy->max; >> + ? ? ? ? ? ? } >> + ? ? } >> + >> + ? ? cpufreq_verify_within_limits(policy, 0, max_freq); >> + >> + ? ? return 0; >> +} >> + >> +/* >> + * cpufreq cooling device callback functions >> + */ >> +static int cpufreq_get_max_state(struct thermal_cooling_device *cdev, >> + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?unsigned long *state) >> +{ >> + ? ? struct cpufreq_cooling_device *cpufreq_device = NULL; > > Why assigning NULL ? yes it is not needed. > >> + >> + ? ? mutex_lock(&cooling_cpufreq_lock); >> + ? ? list_for_each_entry(cpufreq_device, &cooling_cpufreq_list, node) >> + ? ? ? ? ? ? if (cpufreq_device && cpufreq_device->cool_dev == cdev) >> + ? ? ? ? ? ? ? ? ? ? break; >> + >> + ? ? mutex_unlock(&cooling_cpufreq_lock); >> + ? ? if (!cpufreq_device || cpufreq_device->cool_dev != cdev) >> + ? ? ? ? ? ? return -EINVAL; >> + >> + ? ? *state = cpufreq_device->tab_size; >> + ? ? return 0; >> +} > > The above can be simplified this way: > ? ? ? ?int ret = -EINVAL; > ? ? ? ?mutex_lock(&cooling_cpufreq_lock); > ? ? ? ?list_for_each_entry(cpufreq_device, &cooling_cpufreq_list, node) > ? ? ? ? ? ? ? ?if (cpufreq_device->cool_dev == cdev) { > ? ? ? ? ? ? ? ? ? ? ? ?*state = cpufreq_device->tab_size; > ? ? ? ? ? ? ? ? ? ? ? ?ret = 0; > ? ? ? ? ? ? ? ? ? ? ? ?break; > ? ? ? ? ? ? ? ?} > > ? ? ? ?mutex_unlock(&cooling_cpufreq_lock); > ? ? ? ?return ret; > > I think the same can be done for the get_ function below..and similar ones > in the patch 3/4. Ok accepted. > >> + >> +static int cpufreq_get_cur_state(struct thermal_cooling_device *cdev, >> + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?unsigned long *state) >> +{ >> + ? ? struct cpufreq_cooling_device *cpufreq_device = NULL; >> + >> + ? ? mutex_lock(&cooling_cpufreq_lock); >> + ? ? list_for_each_entry(cpufreq_device, &cooling_cpufreq_list, node) >> + ? ? ? ? ? ? if (cpufreq_device && cpufreq_device->cool_dev == cdev) >> + ? ? ? ? ? ? ? ? ? ? break; >> + >> + ? ? mutex_unlock(&cooling_cpufreq_lock); >> + ? ? if (!cpufreq_device || cpufreq_device->cool_dev != cdev) >> + ? ? ? ? ? ? return -EINVAL; >> + ? ? *state = cpufreq_device->cpufreq_state; >> + ? ? return 0; >> +} >> + >> +/*This cooling may be as PASSIVE/ACTIVE type*/ >> +static int cpufreq_set_cur_state(struct thermal_cooling_device *cdev, >> + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?unsigned long state) >> +{ >> + ? ? struct cpufreq_cooling_device *cpufreq_device = NULL; >> + >> + ? ? mutex_lock(&cooling_cpufreq_lock); >> + ? ? list_for_each_entry(cpufreq_device, &cooling_cpufreq_list, node) >> + ? ? ? ? ? ? if (cpufreq_device && cpufreq_device->cool_dev == cdev) >> + ? ? ? ? ? ? ? ? ? ? break; >> + >> + ? ? mutex_unlock(&cooling_cpufreq_lock); >> + ? ? if (!cpufreq_device || cpufreq_device->cool_dev != cdev) >> + ? ? ? ? ? ? return -EINVAL; >> + >> + ? ? cpufreq_apply_cooling(cpufreq_device, state); >> + ? ? return 0; >> +} >> + >> +/* bind cpufreq callbacks to cpufreq cooling device */ >> +static struct thermal_cooling_device_ops cpufreq_cooling_ops = { >> + ? ? .get_max_state = cpufreq_get_max_state, >> + ? ? .get_cur_state = cpufreq_get_cur_state, >> + ? ? .set_cur_state = cpufreq_set_cur_state, >> +}; >> + >> +static struct notifier_block thermal_cpufreq_notifier_block = { >> + ? ? .notifier_call = thermal_cpufreq_notifier, >> +}; >> + >> +struct thermal_cooling_device *cpufreq_cooling_register( >> + ? ? struct freq_pctg_table *tab_ptr, unsigned int tab_size, >> + ? ? const struct cpumask *mask_val) >> +{ >> + ? ? struct thermal_cooling_device *cool_dev; >> + ? ? struct cpufreq_cooling_device *cpufreq_dev = NULL; >> + ? ? unsigned int count = 0; >> + ? ? char dev_name[THERMAL_NAME_LENGTH]; >> + ? ? int ret = 0, id = 0; >> + >> + ? ? if (tab_ptr == NULL || tab_size == 0) >> + ? ? ? ? ? ? return ERR_PTR(-EINVAL); >> + >> + ? ? list_for_each_entry(cpufreq_dev, &cooling_cpufreq_list, node) >> + ? ? ? ? ? ? count++; >> + >> + ? ? cpufreq_dev = >> + ? ? ? ? ? ? kzalloc(sizeof(struct cpufreq_cooling_device), GFP_KERNEL); >> + >> + ? ? if (!cpufreq_dev) >> + ? ? ? ? ? ? return ERR_PTR(-ENOMEM); >> + >> + ? ? cpufreq_dev->tab_ptr = tab_ptr; >> + ? ? cpufreq_dev->tab_size = tab_size; >> + ? ? cpufreq_dev->allowed_cpus = mask_val; >> + >> + ? ? ret = get_idr(&cpufreq_idr, &cooling_cpufreq_lock, &cpufreq_dev->id); >> + ? ? if (ret) { >> + ? ? ? ? ? ? kfree(cpufreq_dev); >> + ? ? ? ? ? ? return ERR_PTR(-EINVAL); >> + ? ? } >> + >> + ? ? sprintf(dev_name, "thermal-cpufreq-%d", cpufreq_dev->id); >> + >> + ? ? cool_dev = thermal_cooling_device_register(dev_name, cpufreq_dev, >> + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? &cpufreq_cooling_ops); >> + ? ? if (!cool_dev) { >> + ? ? ? ? ? ? release_idr(&cpufreq_idr, &cooling_cpufreq_lock, >> + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? cpufreq_dev->id); >> + ? ? ? ? ? ? kfree(cpufreq_dev); >> + ? ? ? ? ? ? return ERR_PTR(-EINVAL); >> + ? ? } >> + ? ? cpufreq_dev->id = id; >> + ? ? cpufreq_dev->cool_dev = cool_dev; >> + ? ? mutex_lock(&cooling_cpufreq_lock); >> + ? ? list_add_tail(&cpufreq_dev->node, &cooling_cpufreq_list); >> + ? ? mutex_unlock(&cooling_cpufreq_lock); >> + >> + ? ? if (count == 0) >> + ? ? ? ? ? ? cpufreq_register_notifier(&thermal_cpufreq_notifier_block, >> + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? CPUFREQ_POLICY_NOTIFIER); > > Why do we register only when count is 0 ? > Or should this be 'if (count > 0)' ? Count represents the number of cpufreq type cooling devices. So for the first call of this API , cpufreq_register_notifier is called. Other call to cpufreq_cooling_register will use the same notifier. May be using bool flag instead of count variable is better. > >> + ? ? return cool_dev; >> +} >> +EXPORT_SYMBOL(cpufreq_cooling_register); >> + >> +void cpufreq_cooling_unregister(struct thermal_cooling_device *cdev) >> +{ >> + ? ? struct cpufreq_cooling_device *cpufreq_dev = NULL; >> + ? ? unsigned int count = 0; >> + >> + ? ? mutex_lock(&cooling_cpufreq_lock); >> + ? ? list_for_each_entry(cpufreq_dev, &cooling_cpufreq_list, node) { >> + ? ? ? ? ? ? if (cpufreq_dev && cpufreq_dev->cool_dev == cdev) >> + ? ? ? ? ? ? ? ? ? ? break; >> + ? ? ? ? ? ? count++; >> + ? ? } >> + >> + ? ? if (!cpufreq_dev || cpufreq_dev->cool_dev != cdev) { >> + ? ? ? ? ? ? mutex_unlock(&cooling_cpufreq_lock); >> + ? ? ? ? ? ? return; >> + ? ? } >> + >> + ? ? list_del(&cpufreq_dev->node); >> + ? ? mutex_unlock(&cooling_cpufreq_lock); >> + >> + ? ? if (count == 1) > > Same here..I do not get the idea behind this.. > Shouldn't this be 'if (count > 0)' ? Same as above. > > In general, > I would like to see a real driver using these API's. This will help > everybody to understand the working of these API's much better. Actually RFC version of the driver is already posted which uses these api's. (https://lkml.org/lkml/2011/12/21/169). I forgot to add this link in this patchset. I will post the new version of the driver shortly. > > Thanks, > Durga > >> + ? ? ? ? ? ? cpufreq_unregister_notifier(&thermal_cpufreq_notifier_block, >> + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? CPUFREQ_POLICY_NOTIFIER); >> + >> + ? ? thermal_cooling_device_unregister(cpufreq_dev->cool_dev); >> + ? ? release_idr(&cpufreq_idr, &cooling_cpufreq_lock, cpufreq_dev->id); >> + ? ? kfree(cpufreq_dev); >> +} >> +EXPORT_SYMBOL(cpufreq_cooling_unregister); >> +#endif /*CONFIG_CPU_FREQ*/ >> diff --git a/include/linux/cpu_cooling.h b/include/linux/cpu_cooling.h >> new file mode 100644 >> index 0000000..5dc5632 >> --- /dev/null >> +++ b/include/linux/cpu_cooling.h >> @@ -0,0 +1,54 @@ >> +/* >> + * ?linux/include/linux/cpu_cooling.h >> + * >> + * ?Copyright (C) 2011 ? ? ? Samsung Electronics Co., Ltd(http://www.samsung.com) >> + * ?Copyright (C) 2011 ?Amit Daniel >> + * >> + * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ >> + * ?This program is free software; you can redistribute it and/or modify >> + * ?it under the terms of the GNU General Public License as published by >> + * ?the Free Software Foundation; version 2 of the License. >> + * >> + * ?This program is distributed in the hope that it will be useful, but >> + * ?WITHOUT ANY WARRANTY; without even the implied warranty of >> + * ?MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. ?See the GNU >> + * ?General Public License for more details. >> + * >> + * ?You should have received a copy of the GNU General Public License along >> + * ?with this program; if not, write to the Free Software Foundation, Inc., >> + * ?59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. >> + * >> + * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ >> + */ >> + >> +#ifndef __CPU_COOLING_H__ >> +#define __CPU_COOLING_H__ >> + >> +#include >> + >> +struct freq_pctg_table { >> + ? ? unsigned int freq_clip_pctg; >> + ? ? unsigned int polling_interval; >> +}; >> + >> +#ifdef CONFIG_CPU_FREQ >> +struct thermal_cooling_device *cpufreq_cooling_register( >> + ? ? struct freq_pctg_table *tab_ptr, unsigned int tab_size, >> + ? ? const struct cpumask *mask_val); >> + >> +void cpufreq_cooling_unregister(struct thermal_cooling_device *cdev); >> +#else /*!CONFIG_CPU_FREQ*/ >> +static inline struct thermal_cooling_device *cpufreq_cooling_register( >> + ? ? struct freq_pctg_table *tab_ptr, unsigned int tab_size, >> + ? ? const struct cpumask *mask_val) >> +{ >> + ? ? return NULL; >> +} >> +static inline void cpufreq_cooling_unregister( >> + ? ? ? ? ? ? ? ? ? ? ? ? ? ? struct thermal_cooling_device *cdev) >> +{ >> + ? ? return; >> +} >> +#endif ? ? ? /*CONFIG_CPU_FREQ*/ >> + >> +#endif /* __CPU_COOLING_H__ */ >> -- >> 1.7.1 > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/