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	thermal: Add devfreq cooling
Add a generic thermal cooling device for devfreq, that is similar to cpu_cooling. The device must use devfreq. In order to use the power extension of the cooling device, it must have registered its OPPs using the OPP library. Cc: Zhang Rui <rui.zhang@intel.com> Cc: Eduardo Valentin <edubezval@gmail.com> Signed-off-by: Javi Merino <javi.merino@arm.com> Signed-off-by: Ørjan Eide <orjan.eide@arm.com> Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
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					@ -147,6 +147,20 @@ config CLOCK_THERMAL
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	  device that is configured to use this cooling mechanism will be
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						  device that is configured to use this cooling mechanism will be
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	  controlled to reduce clock frequency whenever temperature is high.
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						  controlled to reduce clock frequency whenever temperature is high.
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					config DEVFREQ_THERMAL
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						bool "Generic device cooling support"
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						depends on PM_DEVFREQ
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						depends on PM_OPP
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						help
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						  This implements the generic devfreq cooling mechanism through
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						  frequency reduction for devices using devfreq.
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						  This will throttle the device by limiting the maximum allowed DVFS
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						  frequency corresponding to the cooling level.
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						  In order to use the power extensions of the cooling device,
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						  devfreq should use the simple_ondemand governor.
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	  If you want this support, you should say Y here.
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						  If you want this support, you should say Y here.
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config THERMAL_EMULATION
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					config THERMAL_EMULATION
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					@ -22,6 +22,9 @@ thermal_sys-$(CONFIG_CPU_THERMAL)	+= cpu_cooling.o
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# clock cooling
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					# clock cooling
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thermal_sys-$(CONFIG_CLOCK_THERMAL)	+= clock_cooling.o
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					thermal_sys-$(CONFIG_CLOCK_THERMAL)	+= clock_cooling.o
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					# devfreq cooling
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					thermal_sys-$(CONFIG_DEVFREQ_THERMAL) += devfreq_cooling.o
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# platform thermal drivers
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					# platform thermal drivers
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obj-$(CONFIG_QCOM_SPMI_TEMP_ALARM)	+= qcom-spmi-temp-alarm.o
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					obj-$(CONFIG_QCOM_SPMI_TEMP_ALARM)	+= qcom-spmi-temp-alarm.o
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obj-$(CONFIG_SPEAR_THERMAL)	+= spear_thermal.o
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					obj-$(CONFIG_SPEAR_THERMAL)	+= spear_thermal.o
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										563
									
								
								drivers/thermal/devfreq_cooling.c
									
									
									
									
									
										Normal file
									
								
							
							
						
						
									
										563
									
								
								drivers/thermal/devfreq_cooling.c
									
									
									
									
									
										Normal file
									
								
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					@ -0,0 +1,563 @@
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					/*
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					 * devfreq_cooling: Thermal cooling device implementation for devices using
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					 *                  devfreq
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					 *
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					 * Copyright (C) 2014-2015 ARM Limited
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					 *
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					 * This program is free software; you can redistribute it and/or modify
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					 * it under the terms of the GNU General Public License version 2 as
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					 * published by the Free Software Foundation.
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					 *
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					 * This program is distributed "as is" WITHOUT ANY WARRANTY of any
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					 * kind, whether express or implied; without even the implied warranty
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					 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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					 * GNU General Public License for more details.
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					 *
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					 * TODO:
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					 *    - If OPPs are added or removed after devfreq cooling has
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					 *      registered, the devfreq cooling won't react to it.
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					 */
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					#include <linux/devfreq.h>
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					#include <linux/devfreq_cooling.h>
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					#include <linux/export.h>
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					#include <linux/slab.h>
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					#include <linux/pm_opp.h>
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					#include <linux/thermal.h>
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					static DEFINE_MUTEX(devfreq_lock);
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					static DEFINE_IDR(devfreq_idr);
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					/**
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					 * struct devfreq_cooling_device - Devfreq cooling device
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					 * @id:		unique integer value corresponding to each
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					 *		devfreq_cooling_device registered.
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					 * @cdev:	Pointer to associated thermal cooling device.
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					 * @devfreq:	Pointer to associated devfreq device.
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					 * @cooling_state:	Current cooling state.
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					 * @power_table:	Pointer to table with maximum power draw for each
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					 *			cooling state. State is the index into the table, and
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					 *			the power is in mW.
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					 * @freq_table:	Pointer to a table with the frequencies sorted in descending
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					 *		order.  You can index the table by cooling device state
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					 * @freq_table_size:	Size of the @freq_table and @power_table
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					 * @power_ops:	Pointer to devfreq_cooling_power, used to generate the
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					 *		@power_table.
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					 */
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					struct devfreq_cooling_device {
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						int id;
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						struct thermal_cooling_device *cdev;
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						struct devfreq *devfreq;
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						unsigned long cooling_state;
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						u32 *power_table;
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						u32 *freq_table;
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						size_t freq_table_size;
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						struct devfreq_cooling_power *power_ops;
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					};
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					/**
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					 * get_idr - function to get a unique id.
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					 * @idr: struct idr * handle used to create a id.
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					 * @id: int * value generated by this function.
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					 *
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					 * This function will populate @id with an unique
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					 * id, using the idr API.
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					 *
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					 * Return: 0 on success, an error code on failure.
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					 */
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					static int get_idr(struct idr *idr, int *id)
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					{
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						int ret;
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						mutex_lock(&devfreq_lock);
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						ret = idr_alloc(idr, NULL, 0, 0, GFP_KERNEL);
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						mutex_unlock(&devfreq_lock);
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						if (unlikely(ret < 0))
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							return ret;
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						*id = ret;
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						return 0;
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					}
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					/**
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					 * release_idr - function to free the unique id.
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					 * @idr: struct idr * handle used for creating the id.
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					 * @id: int value representing the unique id.
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					 */
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					static void release_idr(struct idr *idr, int id)
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					{
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						mutex_lock(&devfreq_lock);
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						idr_remove(idr, id);
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						mutex_unlock(&devfreq_lock);
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					}
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					/**
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					 * partition_enable_opps() - disable all opps above a given state
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					 * @dfc:	Pointer to devfreq we are operating on
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					 * @cdev_state:	cooling device state we're setting
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					 *
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					 * Go through the OPPs of the device, enabling all OPPs until
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					 * @cdev_state and disabling those frequencies above it.
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					 */
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					static int partition_enable_opps(struct devfreq_cooling_device *dfc,
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									 unsigned long cdev_state)
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					{
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						int i;
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						struct device *dev = dfc->devfreq->dev.parent;
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						for (i = 0; i < dfc->freq_table_size; i++) {
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							struct dev_pm_opp *opp;
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							int ret = 0;
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							unsigned int freq = dfc->freq_table[i];
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							bool want_enable = i >= cdev_state ? true : false;
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							rcu_read_lock();
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							opp = dev_pm_opp_find_freq_exact(dev, freq, !want_enable);
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							rcu_read_unlock();
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							if (PTR_ERR(opp) == -ERANGE)
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								continue;
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							else if (IS_ERR(opp))
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								return PTR_ERR(opp);
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							if (want_enable)
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								ret = dev_pm_opp_enable(dev, freq);
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							else
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								ret = dev_pm_opp_disable(dev, freq);
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							if (ret)
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								return ret;
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						}
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						return 0;
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					}
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					static int devfreq_cooling_get_max_state(struct thermal_cooling_device *cdev,
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										 unsigned long *state)
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					{
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						struct devfreq_cooling_device *dfc = cdev->devdata;
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						*state = dfc->freq_table_size - 1;
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						return 0;
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					}
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					static int devfreq_cooling_get_cur_state(struct thermal_cooling_device *cdev,
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										 unsigned long *state)
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					{
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						struct devfreq_cooling_device *dfc = cdev->devdata;
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						*state = dfc->cooling_state;
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						return 0;
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					}
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					static int devfreq_cooling_set_cur_state(struct thermal_cooling_device *cdev,
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										 unsigned long state)
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					{
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						struct devfreq_cooling_device *dfc = cdev->devdata;
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						struct devfreq *df = dfc->devfreq;
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						struct device *dev = df->dev.parent;
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						int ret;
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						if (state == dfc->cooling_state)
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							return 0;
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						dev_dbg(dev, "Setting cooling state %lu\n", state);
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						if (state >= dfc->freq_table_size)
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							return -EINVAL;
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						ret = partition_enable_opps(dfc, state);
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						if (ret)
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							return ret;
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						dfc->cooling_state = state;
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						return 0;
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					}
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					/**
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					 * freq_get_state() - get the cooling state corresponding to a frequency
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					 * @dfc:	Pointer to devfreq cooling device
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					 * @freq:	frequency in Hz
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					 *
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					 * Return: the cooling state associated with the @freq, or
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					 * THERMAL_CSTATE_INVALID if it wasn't found.
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					 */
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					static unsigned long
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					freq_get_state(struct devfreq_cooling_device *dfc, unsigned long freq)
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					{
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						int i;
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						for (i = 0; i < dfc->freq_table_size; i++) {
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							if (dfc->freq_table[i] == freq)
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								return i;
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						}
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						return THERMAL_CSTATE_INVALID;
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					}
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					/**
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					 * get_static_power() - calculate the static power
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					 * @dfc:	Pointer to devfreq cooling device
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					 * @freq:	Frequency in Hz
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					 *
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					 * Calculate the static power in milliwatts using the supplied
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					 * get_static_power().  The current voltage is calculated using the
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					 * OPP library.  If no get_static_power() was supplied, assume the
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					 * static power is negligible.
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					 */
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					static unsigned long
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					get_static_power(struct devfreq_cooling_device *dfc, unsigned long freq)
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					{
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						struct devfreq *df = dfc->devfreq;
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						struct device *dev = df->dev.parent;
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						unsigned long voltage;
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						struct dev_pm_opp *opp;
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						if (!dfc->power_ops->get_static_power)
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							return 0;
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						rcu_read_lock();
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						opp = dev_pm_opp_find_freq_exact(dev, freq, true);
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						if (IS_ERR(opp) && (PTR_ERR(opp) == -ERANGE))
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							opp = dev_pm_opp_find_freq_exact(dev, freq, false);
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						voltage = dev_pm_opp_get_voltage(opp) / 1000; /* mV */
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						rcu_read_unlock();
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						if (voltage == 0) {
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							dev_warn_ratelimited(dev,
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									     "Failed to get voltage for frequency %lu: %ld\n",
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									     freq, IS_ERR(opp) ? PTR_ERR(opp) : 0);
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							return 0;
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						}
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						return dfc->power_ops->get_static_power(voltage);
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					}
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					/**
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					 * get_dynamic_power - calculate the dynamic power
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					 * @dfc:	Pointer to devfreq cooling device
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					 * @freq:	Frequency in Hz
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					 * @voltage:	Voltage in millivolts
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					 *
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					 * Calculate the dynamic power in milliwatts consumed by the device at
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					 * frequency @freq and voltage @voltage.  If the get_dynamic_power()
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					 * was supplied as part of the devfreq_cooling_power struct, then that
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					 * function is used.  Otherwise, a simple power model (Pdyn = Coeff *
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					 * Voltage^2 * Frequency) is used.
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					 */
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					static unsigned long
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					get_dynamic_power(struct devfreq_cooling_device *dfc, unsigned long freq,
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							  unsigned long voltage)
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					{
 | 
				
			||||||
 | 
						unsigned long power;
 | 
				
			||||||
 | 
						u32 freq_mhz;
 | 
				
			||||||
 | 
						struct devfreq_cooling_power *dfc_power = dfc->power_ops;
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
						if (dfc_power->get_dynamic_power)
 | 
				
			||||||
 | 
							return dfc_power->get_dynamic_power(freq, voltage);
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
						freq_mhz = freq / 1000000;
 | 
				
			||||||
 | 
						power = (u64)dfc_power->dyn_power_coeff * freq_mhz * voltage * voltage;
 | 
				
			||||||
 | 
						do_div(power, 1000000000);
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
						return power;
 | 
				
			||||||
 | 
					}
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
					static int devfreq_cooling_get_requested_power(struct thermal_cooling_device *cdev,
 | 
				
			||||||
 | 
										       struct thermal_zone_device *tz,
 | 
				
			||||||
 | 
										       u32 *power)
 | 
				
			||||||
 | 
					{
 | 
				
			||||||
 | 
						struct devfreq_cooling_device *dfc = cdev->devdata;
 | 
				
			||||||
 | 
						struct devfreq *df = dfc->devfreq;
 | 
				
			||||||
 | 
						struct devfreq_dev_status *status = &df->last_status;
 | 
				
			||||||
 | 
						unsigned long state;
 | 
				
			||||||
 | 
						unsigned long freq = status->current_frequency;
 | 
				
			||||||
 | 
						u32 dyn_power, static_power;
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
						/* Get dynamic power for state */
 | 
				
			||||||
 | 
						state = freq_get_state(dfc, freq);
 | 
				
			||||||
 | 
						if (state == THERMAL_CSTATE_INVALID)
 | 
				
			||||||
 | 
							return -EAGAIN;
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
						dyn_power = dfc->power_table[state];
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
						/* Scale dynamic power for utilization */
 | 
				
			||||||
 | 
						dyn_power = (dyn_power * status->busy_time) / status->total_time;
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
						/* Get static power */
 | 
				
			||||||
 | 
						static_power = get_static_power(dfc, freq);
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
						*power = dyn_power + static_power;
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
						return 0;
 | 
				
			||||||
 | 
					}
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
					static int devfreq_cooling_state2power(struct thermal_cooling_device *cdev,
 | 
				
			||||||
 | 
									       struct thermal_zone_device *tz,
 | 
				
			||||||
 | 
									       unsigned long state,
 | 
				
			||||||
 | 
									       u32 *power)
 | 
				
			||||||
 | 
					{
 | 
				
			||||||
 | 
						struct devfreq_cooling_device *dfc = cdev->devdata;
 | 
				
			||||||
 | 
						unsigned long freq;
 | 
				
			||||||
 | 
						u32 static_power;
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
						if (state < 0 || state >= dfc->freq_table_size)
 | 
				
			||||||
 | 
							return -EINVAL;
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
						freq = dfc->freq_table[state];
 | 
				
			||||||
 | 
						static_power = get_static_power(dfc, freq);
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
						*power = dfc->power_table[state] + static_power;
 | 
				
			||||||
 | 
						return 0;
 | 
				
			||||||
 | 
					}
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
					static int devfreq_cooling_power2state(struct thermal_cooling_device *cdev,
 | 
				
			||||||
 | 
									       struct thermal_zone_device *tz,
 | 
				
			||||||
 | 
									       u32 power, unsigned long *state)
 | 
				
			||||||
 | 
					{
 | 
				
			||||||
 | 
						struct devfreq_cooling_device *dfc = cdev->devdata;
 | 
				
			||||||
 | 
						struct devfreq *df = dfc->devfreq;
 | 
				
			||||||
 | 
						struct devfreq_dev_status *status = &df->last_status;
 | 
				
			||||||
 | 
						unsigned long freq = status->current_frequency;
 | 
				
			||||||
 | 
						unsigned long busy_time;
 | 
				
			||||||
 | 
						s32 dyn_power;
 | 
				
			||||||
 | 
						u32 static_power;
 | 
				
			||||||
 | 
						int i;
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
						static_power = get_static_power(dfc, freq);
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
						dyn_power = power - static_power;
 | 
				
			||||||
 | 
						dyn_power = dyn_power > 0 ? dyn_power : 0;
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
						/* Scale dynamic power for utilization */
 | 
				
			||||||
 | 
						busy_time = status->busy_time ?: 1;
 | 
				
			||||||
 | 
						dyn_power = (dyn_power * status->total_time) / busy_time;
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
						/*
 | 
				
			||||||
 | 
						 * Find the first cooling state that is within the power
 | 
				
			||||||
 | 
						 * budget for dynamic power.
 | 
				
			||||||
 | 
						 */
 | 
				
			||||||
 | 
						for (i = 0; i < dfc->freq_table_size - 1; i++)
 | 
				
			||||||
 | 
							if (dyn_power >= dfc->power_table[i])
 | 
				
			||||||
 | 
								break;
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
						*state = i;
 | 
				
			||||||
 | 
						return 0;
 | 
				
			||||||
 | 
					}
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
					static struct thermal_cooling_device_ops devfreq_cooling_ops = {
 | 
				
			||||||
 | 
						.get_max_state = devfreq_cooling_get_max_state,
 | 
				
			||||||
 | 
						.get_cur_state = devfreq_cooling_get_cur_state,
 | 
				
			||||||
 | 
						.set_cur_state = devfreq_cooling_set_cur_state,
 | 
				
			||||||
 | 
					};
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
					/**
 | 
				
			||||||
 | 
					 * devfreq_cooling_gen_tables() - Generate power and freq tables.
 | 
				
			||||||
 | 
					 * @dfc: Pointer to devfreq cooling device.
 | 
				
			||||||
 | 
					 *
 | 
				
			||||||
 | 
					 * Generate power and frequency tables: the power table hold the
 | 
				
			||||||
 | 
					 * device's maximum power usage at each cooling state (OPP).  The
 | 
				
			||||||
 | 
					 * static and dynamic power using the appropriate voltage and
 | 
				
			||||||
 | 
					 * frequency for the state, is acquired from the struct
 | 
				
			||||||
 | 
					 * devfreq_cooling_power, and summed to make the maximum power draw.
 | 
				
			||||||
 | 
					 *
 | 
				
			||||||
 | 
					 * The frequency table holds the frequencies in descending order.
 | 
				
			||||||
 | 
					 * That way its indexed by cooling device state.
 | 
				
			||||||
 | 
					 *
 | 
				
			||||||
 | 
					 * The tables are malloced, and pointers put in dfc.  They must be
 | 
				
			||||||
 | 
					 * freed when unregistering the devfreq cooling device.
 | 
				
			||||||
 | 
					 *
 | 
				
			||||||
 | 
					 * Return: 0 on success, negative error code on failure.
 | 
				
			||||||
 | 
					 */
 | 
				
			||||||
 | 
					static int devfreq_cooling_gen_tables(struct devfreq_cooling_device *dfc)
 | 
				
			||||||
 | 
					{
 | 
				
			||||||
 | 
						struct devfreq *df = dfc->devfreq;
 | 
				
			||||||
 | 
						struct device *dev = df->dev.parent;
 | 
				
			||||||
 | 
						int ret, num_opps;
 | 
				
			||||||
 | 
						unsigned long freq;
 | 
				
			||||||
 | 
						u32 *power_table = NULL;
 | 
				
			||||||
 | 
						u32 *freq_table;
 | 
				
			||||||
 | 
						int i;
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
						num_opps = dev_pm_opp_get_opp_count(dev);
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
						if (dfc->power_ops) {
 | 
				
			||||||
 | 
							power_table = kcalloc(num_opps, sizeof(*power_table),
 | 
				
			||||||
 | 
									      GFP_KERNEL);
 | 
				
			||||||
 | 
							if (!power_table)
 | 
				
			||||||
 | 
								ret = -ENOMEM;
 | 
				
			||||||
 | 
						}
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
						freq_table = kcalloc(num_opps, sizeof(*freq_table),
 | 
				
			||||||
 | 
								     GFP_KERNEL);
 | 
				
			||||||
 | 
						if (!freq_table) {
 | 
				
			||||||
 | 
							ret = -ENOMEM;
 | 
				
			||||||
 | 
							goto free_power_table;
 | 
				
			||||||
 | 
						}
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
						for (i = 0, freq = ULONG_MAX; i < num_opps; i++, freq--) {
 | 
				
			||||||
 | 
							unsigned long power_dyn, voltage;
 | 
				
			||||||
 | 
							struct dev_pm_opp *opp;
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
							rcu_read_lock();
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
							opp = dev_pm_opp_find_freq_floor(dev, &freq);
 | 
				
			||||||
 | 
							if (IS_ERR(opp)) {
 | 
				
			||||||
 | 
								rcu_read_unlock();
 | 
				
			||||||
 | 
								ret = PTR_ERR(opp);
 | 
				
			||||||
 | 
								goto free_tables;
 | 
				
			||||||
 | 
							}
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
							voltage = dev_pm_opp_get_voltage(opp) / 1000; /* mV */
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
							rcu_read_unlock();
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
							if (dfc->power_ops) {
 | 
				
			||||||
 | 
								power_dyn = get_dynamic_power(dfc, freq, voltage);
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
								dev_dbg(dev, "Dynamic power table: %lu MHz @ %lu mV: %lu = %lu mW\n",
 | 
				
			||||||
 | 
									freq / 1000000, voltage, power_dyn, power_dyn);
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
								power_table[i] = power_dyn;
 | 
				
			||||||
 | 
							}
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
							freq_table[i] = freq;
 | 
				
			||||||
 | 
						}
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
						if (dfc->power_ops)
 | 
				
			||||||
 | 
							dfc->power_table = power_table;
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
						dfc->freq_table = freq_table;
 | 
				
			||||||
 | 
						dfc->freq_table_size = num_opps;
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
						return 0;
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
					free_tables:
 | 
				
			||||||
 | 
						kfree(freq_table);
 | 
				
			||||||
 | 
					free_power_table:
 | 
				
			||||||
 | 
						kfree(power_table);
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
						return ret;
 | 
				
			||||||
 | 
					}
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
					/**
 | 
				
			||||||
 | 
					 * of_devfreq_cooling_register_power() - Register devfreq cooling device,
 | 
				
			||||||
 | 
					 *                                      with OF and power information.
 | 
				
			||||||
 | 
					 * @np:	Pointer to OF device_node.
 | 
				
			||||||
 | 
					 * @df:	Pointer to devfreq device.
 | 
				
			||||||
 | 
					 * @dfc_power:	Pointer to devfreq_cooling_power.
 | 
				
			||||||
 | 
					 *
 | 
				
			||||||
 | 
					 * Register a devfreq cooling device.  The available OPPs must be
 | 
				
			||||||
 | 
					 * registered on the device.
 | 
				
			||||||
 | 
					 *
 | 
				
			||||||
 | 
					 * If @dfc_power is provided, the cooling device is registered with the
 | 
				
			||||||
 | 
					 * power extensions.  For the power extensions to work correctly,
 | 
				
			||||||
 | 
					 * devfreq should use the simple_ondemand governor, other governors
 | 
				
			||||||
 | 
					 * are not currently supported.
 | 
				
			||||||
 | 
					 */
 | 
				
			||||||
 | 
					struct devfreq_cooling_device *
 | 
				
			||||||
 | 
					of_devfreq_cooling_register_power(struct device_node *np, struct devfreq *df,
 | 
				
			||||||
 | 
									  struct devfreq_cooling_power *dfc_power)
 | 
				
			||||||
 | 
					{
 | 
				
			||||||
 | 
						struct thermal_cooling_device *cdev;
 | 
				
			||||||
 | 
						struct devfreq_cooling_device *dfc;
 | 
				
			||||||
 | 
						char dev_name[THERMAL_NAME_LENGTH];
 | 
				
			||||||
 | 
						int err;
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
						dfc = kzalloc(sizeof(*dfc), GFP_KERNEL);
 | 
				
			||||||
 | 
						if (!dfc)
 | 
				
			||||||
 | 
							return ERR_PTR(-ENOMEM);
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
						dfc->devfreq = df;
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
						if (dfc_power) {
 | 
				
			||||||
 | 
							dfc->power_ops = dfc_power;
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
							devfreq_cooling_ops.get_requested_power =
 | 
				
			||||||
 | 
								devfreq_cooling_get_requested_power;
 | 
				
			||||||
 | 
							devfreq_cooling_ops.state2power = devfreq_cooling_state2power;
 | 
				
			||||||
 | 
							devfreq_cooling_ops.power2state = devfreq_cooling_power2state;
 | 
				
			||||||
 | 
						}
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
						err = devfreq_cooling_gen_tables(dfc);
 | 
				
			||||||
 | 
						if (err)
 | 
				
			||||||
 | 
							goto free_dfc;
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
						err = get_idr(&devfreq_idr, &dfc->id);
 | 
				
			||||||
 | 
						if (err)
 | 
				
			||||||
 | 
							goto free_tables;
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
						snprintf(dev_name, sizeof(dev_name), "thermal-devfreq-%d", dfc->id);
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
						cdev = thermal_of_cooling_device_register(np, dev_name, dfc,
 | 
				
			||||||
 | 
											  &devfreq_cooling_ops);
 | 
				
			||||||
 | 
						if (IS_ERR(cdev)) {
 | 
				
			||||||
 | 
							err = PTR_ERR(cdev);
 | 
				
			||||||
 | 
							dev_err(df->dev.parent,
 | 
				
			||||||
 | 
								"Failed to register devfreq cooling device (%d)\n",
 | 
				
			||||||
 | 
								err);
 | 
				
			||||||
 | 
							goto release_idr;
 | 
				
			||||||
 | 
						}
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
						dfc->cdev = cdev;
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
						return dfc;
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
					release_idr:
 | 
				
			||||||
 | 
						release_idr(&devfreq_idr, dfc->id);
 | 
				
			||||||
 | 
					free_tables:
 | 
				
			||||||
 | 
						kfree(dfc->power_table);
 | 
				
			||||||
 | 
						kfree(dfc->freq_table);
 | 
				
			||||||
 | 
					free_dfc:
 | 
				
			||||||
 | 
						kfree(dfc);
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
						return ERR_PTR(err);
 | 
				
			||||||
 | 
					}
 | 
				
			||||||
 | 
					EXPORT_SYMBOL_GPL(of_devfreq_cooling_register_power);
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
					/**
 | 
				
			||||||
 | 
					 * of_devfreq_cooling_register() - Register devfreq cooling device,
 | 
				
			||||||
 | 
					 *                                with OF information.
 | 
				
			||||||
 | 
					 * @np: Pointer to OF device_node.
 | 
				
			||||||
 | 
					 * @df: Pointer to devfreq device.
 | 
				
			||||||
 | 
					 */
 | 
				
			||||||
 | 
					struct devfreq_cooling_device *
 | 
				
			||||||
 | 
					of_devfreq_cooling_register(struct device_node *np, struct devfreq *df)
 | 
				
			||||||
 | 
					{
 | 
				
			||||||
 | 
						return of_devfreq_cooling_register_power(np, df, NULL);
 | 
				
			||||||
 | 
					}
 | 
				
			||||||
 | 
					EXPORT_SYMBOL_GPL(of_devfreq_cooling_register);
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
					/**
 | 
				
			||||||
 | 
					 * devfreq_cooling_register() - Register devfreq cooling device.
 | 
				
			||||||
 | 
					 * @df: Pointer to devfreq device.
 | 
				
			||||||
 | 
					 */
 | 
				
			||||||
 | 
					struct devfreq_cooling_device *devfreq_cooling_register(struct devfreq *df)
 | 
				
			||||||
 | 
					{
 | 
				
			||||||
 | 
						return of_devfreq_cooling_register(NULL, df);
 | 
				
			||||||
 | 
					}
 | 
				
			||||||
 | 
					EXPORT_SYMBOL_GPL(devfreq_cooling_register);
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
					/**
 | 
				
			||||||
 | 
					 * devfreq_cooling_unregister() - Unregister devfreq cooling device.
 | 
				
			||||||
 | 
					 * @dfc: Pointer to devfreq cooling device to unregister.
 | 
				
			||||||
 | 
					 */
 | 
				
			||||||
 | 
					void devfreq_cooling_unregister(struct devfreq_cooling_device *dfc)
 | 
				
			||||||
 | 
					{
 | 
				
			||||||
 | 
						if (!dfc)
 | 
				
			||||||
 | 
							return;
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
						thermal_cooling_device_unregister(dfc->cdev);
 | 
				
			||||||
 | 
						release_idr(&devfreq_idr, dfc->id);
 | 
				
			||||||
 | 
						kfree(dfc->power_table);
 | 
				
			||||||
 | 
						kfree(dfc->freq_table);
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
						kfree(dfc);
 | 
				
			||||||
 | 
					}
 | 
				
			||||||
 | 
					EXPORT_SYMBOL_GPL(devfreq_cooling_unregister);
 | 
				
			||||||
							
								
								
									
										81
									
								
								include/linux/devfreq_cooling.h
									
									
									
									
									
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					/*
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					 * devfreq_cooling: Thermal cooling device implementation for devices using
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					 *                  devfreq
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					 *
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					 * Copyright (C) 2014-2015 ARM Limited
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					 *
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					 * This program is free software; you can redistribute it and/or modify
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					 * it under the terms of the GNU General Public License version 2 as
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					 * published by the Free Software Foundation.
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					 *
 | 
				
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					 * This program is distributed "as is" WITHOUT ANY WARRANTY of any
 | 
				
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					 * kind, whether express or implied; without even the implied warranty
 | 
				
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					 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 | 
				
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 | 
					 * GNU General Public License for more details.
 | 
				
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					 */
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					#ifndef __DEVFREQ_COOLING_H__
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					#define __DEVFREQ_COOLING_H__
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 | 
				
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					#include <linux/devfreq.h>
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					#include <linux/thermal.h>
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					#ifdef CONFIG_DEVFREQ_THERMAL
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					/**
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					 * struct devfreq_cooling_power - Devfreq cooling power ops
 | 
				
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					 * @get_static_power:	Take voltage, in mV, and return the static power
 | 
				
			||||||
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					 *			in mW.  If NULL, the static power is assumed
 | 
				
			||||||
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					 *			to be 0.
 | 
				
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 | 
					 * @get_dynamic_power:	Take voltage, in mV, and frequency, in HZ, and
 | 
				
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 | 
					 *			return the dynamic power draw in mW.  If NULL,
 | 
				
			||||||
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					 *			a simple power model is used.
 | 
				
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					 * @dyn_power_coeff:	Coefficient for the simple dynamic power model in
 | 
				
			||||||
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					 *			mW/(MHz mV mV).
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					 *			If get_dynamic_power() is NULL, then the
 | 
				
			||||||
 | 
					 *			dynamic power is calculated as
 | 
				
			||||||
 | 
					 *			@dyn_power_coeff * frequency * voltage^2
 | 
				
			||||||
 | 
					 */
 | 
				
			||||||
 | 
					struct devfreq_cooling_power {
 | 
				
			||||||
 | 
						unsigned long (*get_static_power)(unsigned long voltage);
 | 
				
			||||||
 | 
						unsigned long (*get_dynamic_power)(unsigned long freq,
 | 
				
			||||||
 | 
										   unsigned long voltage);
 | 
				
			||||||
 | 
						unsigned long dyn_power_coeff;
 | 
				
			||||||
 | 
					};
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
					struct devfreq_cooling_device *
 | 
				
			||||||
 | 
					of_devfreq_cooling_register_power(struct device_node *np, struct devfreq *df,
 | 
				
			||||||
 | 
									  struct devfreq_cooling_power *dfc_power);
 | 
				
			||||||
 | 
					struct devfreq_cooling_device *
 | 
				
			||||||
 | 
					of_devfreq_cooling_register(struct device_node *np, struct devfreq *df);
 | 
				
			||||||
 | 
					struct devfreq_cooling_device *devfreq_cooling_register(struct devfreq *df);
 | 
				
			||||||
 | 
					void devfreq_cooling_unregister(struct devfreq_cooling_device *dfc);
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
					#else /* !CONFIG_DEVFREQ_THERMAL */
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
					struct devfreq_cooling_device *
 | 
				
			||||||
 | 
					of_devfreq_cooling_register_power(struct device_node *np, struct devfreq *df,
 | 
				
			||||||
 | 
									  struct devfreq_cooling_power *dfc_power)
 | 
				
			||||||
 | 
					{
 | 
				
			||||||
 | 
						return ERR_PTR(-EINVAL);
 | 
				
			||||||
 | 
					}
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
					static inline struct devfreq_cooling_device *
 | 
				
			||||||
 | 
					of_devfreq_cooling_register(struct device_node *np, struct devfreq *df)
 | 
				
			||||||
 | 
					{
 | 
				
			||||||
 | 
						return ERR_PTR(-EINVAL);
 | 
				
			||||||
 | 
					}
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
					static inline struct devfreq_cooling_device *
 | 
				
			||||||
 | 
					devfreq_cooling_register(struct devfreq *df)
 | 
				
			||||||
 | 
					{
 | 
				
			||||||
 | 
						return ERR_PTR(-EINVAL);
 | 
				
			||||||
 | 
					}
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
					static inline void
 | 
				
			||||||
 | 
					devfreq_cooling_unregister(struct devfreq_cooling_device *dfc)
 | 
				
			||||||
 | 
					{
 | 
				
			||||||
 | 
					}
 | 
				
			||||||
 | 
					
 | 
				
			||||||
 | 
					#endif /* CONFIG_DEVFREQ_THERMAL */
 | 
				
			||||||
 | 
					#endif /* __DEVFREQ_COOLING_H__ */
 | 
				
			||||||
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