mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-26 10:49:33 +00:00
![Wei Yongjun](/assets/img/avatar_default.png)
The driver allocates the mutex but not initialize it. Use mutex_init() on it to initialize it correctly. This is detected by Coccinelle semantic patch. Signed-off-by: Wei Yongjun <weiyj.lk@gmail.com> Signed-off-by: Zhang Rui <rui.zhang@intel.com>
486 lines
14 KiB
C
486 lines
14 KiB
C
/*
|
|
* drivers/thermal/clock_cooling.c
|
|
*
|
|
* Copyright (C) 2014 Eduardo Valentin <edubezval@gmail.com>
|
|
*
|
|
* Copyright (C) 2013 Texas Instruments Inc.
|
|
* Contact: Eduardo Valentin <eduardo.valentin@ti.com>
|
|
*
|
|
* Highly based on cpu_cooling.c.
|
|
* Copyright (C) 2012 Samsung Electronics Co., Ltd(http://www.samsung.com)
|
|
* Copyright (C) 2012 Amit Daniel <amit.kachhap@linaro.org>
|
|
*
|
|
* 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.
|
|
*/
|
|
#include <linux/clk.h>
|
|
#include <linux/cpufreq.h>
|
|
#include <linux/device.h>
|
|
#include <linux/err.h>
|
|
#include <linux/idr.h>
|
|
#include <linux/mutex.h>
|
|
#include <linux/pm_opp.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/thermal.h>
|
|
#include <linux/clock_cooling.h>
|
|
|
|
/**
|
|
* struct clock_cooling_device - data for cooling device with clock
|
|
* @id: unique integer value corresponding to each clock_cooling_device
|
|
* registered.
|
|
* @dev: struct device pointer to the device being used to cool off using
|
|
* clock frequencies.
|
|
* @cdev: thermal_cooling_device pointer to keep track of the
|
|
* registered cooling device.
|
|
* @clk_rate_change_nb: reference to notifier block used to receive clock
|
|
* rate changes.
|
|
* @freq_table: frequency table used to keep track of available frequencies.
|
|
* @clock_state: integer value representing the current state of clock
|
|
* cooling devices.
|
|
* @clock_val: integer value representing the absolute value of the clipped
|
|
* frequency.
|
|
* @clk: struct clk reference used to enforce clock limits.
|
|
* @lock: mutex lock to protect this struct.
|
|
*
|
|
* This structure is required for keeping information of each
|
|
* clock_cooling_device registered. In order to prevent corruption of this a
|
|
* mutex @lock is used.
|
|
*/
|
|
struct clock_cooling_device {
|
|
int id;
|
|
struct device *dev;
|
|
struct thermal_cooling_device *cdev;
|
|
struct notifier_block clk_rate_change_nb;
|
|
struct cpufreq_frequency_table *freq_table;
|
|
unsigned long clock_state;
|
|
unsigned long clock_val;
|
|
struct clk *clk;
|
|
struct mutex lock; /* lock to protect the content of this struct */
|
|
};
|
|
#define to_clock_cooling_device(x) \
|
|
container_of(x, struct clock_cooling_device, clk_rate_change_nb)
|
|
static DEFINE_IDR(clock_idr);
|
|
static DEFINE_MUTEX(cooling_clock_lock);
|
|
|
|
/**
|
|
* clock_cooling_get_idr - function to get an unique id.
|
|
* @id: int * value generated by this function.
|
|
*
|
|
* This function will populate @id with an unique
|
|
* id, using the idr API.
|
|
*
|
|
* Return: 0 on success, an error code on failure.
|
|
*/
|
|
static int clock_cooling_get_idr(int *id)
|
|
{
|
|
int ret;
|
|
|
|
mutex_lock(&cooling_clock_lock);
|
|
ret = idr_alloc(&clock_idr, NULL, 0, 0, GFP_KERNEL);
|
|
mutex_unlock(&cooling_clock_lock);
|
|
if (unlikely(ret < 0))
|
|
return ret;
|
|
*id = ret;
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* release_idr - function to free the unique id.
|
|
* @id: int value representing the unique id.
|
|
*/
|
|
static void release_idr(int id)
|
|
{
|
|
mutex_lock(&cooling_clock_lock);
|
|
idr_remove(&clock_idr, id);
|
|
mutex_unlock(&cooling_clock_lock);
|
|
}
|
|
|
|
/* Below code defines functions to be used for clock as cooling device */
|
|
|
|
enum clock_cooling_property {
|
|
GET_LEVEL,
|
|
GET_FREQ,
|
|
GET_MAXL,
|
|
};
|
|
|
|
/**
|
|
* clock_cooling_get_property - fetch a property of interest for a give cpu.
|
|
* @ccdev: clock cooling device reference
|
|
* @input: query parameter
|
|
* @output: query return
|
|
* @property: type of query (frequency, level, max level)
|
|
*
|
|
* This is the common function to
|
|
* 1. get maximum clock cooling states
|
|
* 2. translate frequency to cooling state
|
|
* 3. translate cooling state to frequency
|
|
* Note that the code may be not in good shape
|
|
* but it is written in this way in order to:
|
|
* a) reduce duplicate code as most of the code can be shared.
|
|
* b) make sure the logic is consistent when translating between
|
|
* cooling states and frequencies.
|
|
*
|
|
* Return: 0 on success, -EINVAL when invalid parameters are passed.
|
|
*/
|
|
static int clock_cooling_get_property(struct clock_cooling_device *ccdev,
|
|
unsigned long input,
|
|
unsigned long *output,
|
|
enum clock_cooling_property property)
|
|
{
|
|
int i;
|
|
unsigned long max_level = 0, level = 0;
|
|
unsigned int freq = CPUFREQ_ENTRY_INVALID;
|
|
int descend = -1;
|
|
struct cpufreq_frequency_table *pos, *table = ccdev->freq_table;
|
|
|
|
if (!output)
|
|
return -EINVAL;
|
|
|
|
if (!table)
|
|
return -EINVAL;
|
|
|
|
cpufreq_for_each_valid_entry(pos, table) {
|
|
/* ignore duplicate entry */
|
|
if (freq == pos->frequency)
|
|
continue;
|
|
|
|
/* get the frequency order */
|
|
if (freq != CPUFREQ_ENTRY_INVALID && descend == -1)
|
|
descend = freq > pos->frequency;
|
|
|
|
freq = pos->frequency;
|
|
max_level++;
|
|
}
|
|
|
|
/* No valid cpu frequency entry */
|
|
if (max_level == 0)
|
|
return -EINVAL;
|
|
|
|
/* max_level is an index, not a counter */
|
|
max_level--;
|
|
|
|
/* get max level */
|
|
if (property == GET_MAXL) {
|
|
*output = max_level;
|
|
return 0;
|
|
}
|
|
|
|
if (property == GET_FREQ)
|
|
level = descend ? input : (max_level - input);
|
|
|
|
i = 0;
|
|
cpufreq_for_each_valid_entry(pos, table) {
|
|
/* ignore duplicate entry */
|
|
if (freq == pos->frequency)
|
|
continue;
|
|
|
|
/* now we have a valid frequency entry */
|
|
freq = pos->frequency;
|
|
|
|
if (property == GET_LEVEL && (unsigned int)input == freq) {
|
|
/* get level by frequency */
|
|
*output = descend ? i : (max_level - i);
|
|
return 0;
|
|
}
|
|
if (property == GET_FREQ && level == i) {
|
|
/* get frequency by level */
|
|
*output = freq;
|
|
return 0;
|
|
}
|
|
i++;
|
|
}
|
|
|
|
return -EINVAL;
|
|
}
|
|
|
|
/**
|
|
* clock_cooling_get_level - return the cooling level of given clock cooling.
|
|
* @cdev: reference of a thermal cooling device of used as clock cooling device
|
|
* @freq: the frequency of interest
|
|
*
|
|
* This function will match the cooling level corresponding to the
|
|
* requested @freq and return it.
|
|
*
|
|
* Return: The matched cooling level on success or THERMAL_CSTATE_INVALID
|
|
* otherwise.
|
|
*/
|
|
unsigned long clock_cooling_get_level(struct thermal_cooling_device *cdev,
|
|
unsigned long freq)
|
|
{
|
|
struct clock_cooling_device *ccdev = cdev->devdata;
|
|
unsigned long val;
|
|
|
|
if (clock_cooling_get_property(ccdev, (unsigned long)freq, &val,
|
|
GET_LEVEL))
|
|
return THERMAL_CSTATE_INVALID;
|
|
|
|
return val;
|
|
}
|
|
EXPORT_SYMBOL_GPL(clock_cooling_get_level);
|
|
|
|
/**
|
|
* clock_cooling_get_frequency - get the absolute value of frequency from level.
|
|
* @ccdev: clock cooling device reference
|
|
* @level: cooling level
|
|
*
|
|
* This function matches cooling level with frequency. Based on a cooling level
|
|
* of frequency, equals cooling state of cpu cooling device, it will return
|
|
* the corresponding frequency.
|
|
* e.g level=0 --> 1st MAX FREQ, level=1 ---> 2nd MAX FREQ, .... etc
|
|
*
|
|
* Return: 0 on error, the corresponding frequency otherwise.
|
|
*/
|
|
static unsigned long
|
|
clock_cooling_get_frequency(struct clock_cooling_device *ccdev,
|
|
unsigned long level)
|
|
{
|
|
int ret = 0;
|
|
unsigned long freq;
|
|
|
|
ret = clock_cooling_get_property(ccdev, level, &freq, GET_FREQ);
|
|
if (ret)
|
|
return 0;
|
|
|
|
return freq;
|
|
}
|
|
|
|
/**
|
|
* clock_cooling_apply - function to apply frequency clipping.
|
|
* @ccdev: clock_cooling_device pointer containing frequency clipping data.
|
|
* @cooling_state: value of the cooling state.
|
|
*
|
|
* Function used to make sure the clock layer is aware of current thermal
|
|
* limits. The limits are applied by updating the clock rate in case it is
|
|
* higher than the corresponding frequency based on the requested cooling_state.
|
|
*
|
|
* Return: 0 on success, an error code otherwise (-EINVAL in case wrong
|
|
* cooling state).
|
|
*/
|
|
static int clock_cooling_apply(struct clock_cooling_device *ccdev,
|
|
unsigned long cooling_state)
|
|
{
|
|
unsigned long clip_freq, cur_freq;
|
|
int ret = 0;
|
|
|
|
/* Here we write the clipping */
|
|
/* Check if the old cooling action is same as new cooling action */
|
|
if (ccdev->clock_state == cooling_state)
|
|
return 0;
|
|
|
|
clip_freq = clock_cooling_get_frequency(ccdev, cooling_state);
|
|
if (!clip_freq)
|
|
return -EINVAL;
|
|
|
|
cur_freq = clk_get_rate(ccdev->clk);
|
|
|
|
mutex_lock(&ccdev->lock);
|
|
ccdev->clock_state = cooling_state;
|
|
ccdev->clock_val = clip_freq;
|
|
/* enforce clock level */
|
|
if (cur_freq > clip_freq)
|
|
ret = clk_set_rate(ccdev->clk, clip_freq);
|
|
mutex_unlock(&ccdev->lock);
|
|
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* clock_cooling_clock_notifier - notifier callback on clock rate changes.
|
|
* @nb: struct notifier_block * with callback info.
|
|
* @event: value showing clock event for which this function invoked.
|
|
* @data: callback-specific data
|
|
*
|
|
* Callback to hijack the notification on clock transition.
|
|
* Every time there is a clock change, we intercept all pre change events
|
|
* and block the transition in case the new rate infringes thermal limits.
|
|
*
|
|
* Return: NOTIFY_DONE (success) or NOTIFY_BAD (new_rate > thermal limit).
|
|
*/
|
|
static int clock_cooling_clock_notifier(struct notifier_block *nb,
|
|
unsigned long event, void *data)
|
|
{
|
|
struct clk_notifier_data *ndata = data;
|
|
struct clock_cooling_device *ccdev = to_clock_cooling_device(nb);
|
|
|
|
switch (event) {
|
|
case PRE_RATE_CHANGE:
|
|
/*
|
|
* checks on current state
|
|
* TODO: current method is not best we can find as it
|
|
* allows possibly voltage transitions, in case DVFS
|
|
* layer is also hijacking clock pre notifications.
|
|
*/
|
|
if (ndata->new_rate > ccdev->clock_val)
|
|
return NOTIFY_BAD;
|
|
/* fall through */
|
|
case POST_RATE_CHANGE:
|
|
case ABORT_RATE_CHANGE:
|
|
default:
|
|
return NOTIFY_DONE;
|
|
}
|
|
}
|
|
|
|
/* clock cooling device thermal callback functions are defined below */
|
|
|
|
/**
|
|
* clock_cooling_get_max_state - callback function to get the max cooling state.
|
|
* @cdev: thermal cooling device pointer.
|
|
* @state: fill this variable with the max cooling state.
|
|
*
|
|
* Callback for the thermal cooling device to return the clock
|
|
* max cooling state.
|
|
*
|
|
* Return: 0 on success, an error code otherwise.
|
|
*/
|
|
static int clock_cooling_get_max_state(struct thermal_cooling_device *cdev,
|
|
unsigned long *state)
|
|
{
|
|
struct clock_cooling_device *ccdev = cdev->devdata;
|
|
unsigned long count = 0;
|
|
int ret;
|
|
|
|
ret = clock_cooling_get_property(ccdev, 0, &count, GET_MAXL);
|
|
if (!ret)
|
|
*state = count;
|
|
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* clock_cooling_get_cur_state - function to get the current cooling state.
|
|
* @cdev: thermal cooling device pointer.
|
|
* @state: fill this variable with the current cooling state.
|
|
*
|
|
* Callback for the thermal cooling device to return the clock
|
|
* current cooling state.
|
|
*
|
|
* Return: 0 (success)
|
|
*/
|
|
static int clock_cooling_get_cur_state(struct thermal_cooling_device *cdev,
|
|
unsigned long *state)
|
|
{
|
|
struct clock_cooling_device *ccdev = cdev->devdata;
|
|
|
|
*state = ccdev->clock_state;
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* clock_cooling_set_cur_state - function to set the current cooling state.
|
|
* @cdev: thermal cooling device pointer.
|
|
* @state: set this variable to the current cooling state.
|
|
*
|
|
* Callback for the thermal cooling device to change the clock cooling
|
|
* current cooling state.
|
|
*
|
|
* Return: 0 on success, an error code otherwise.
|
|
*/
|
|
static int clock_cooling_set_cur_state(struct thermal_cooling_device *cdev,
|
|
unsigned long state)
|
|
{
|
|
struct clock_cooling_device *clock_device = cdev->devdata;
|
|
|
|
return clock_cooling_apply(clock_device, state);
|
|
}
|
|
|
|
/* Bind clock callbacks to thermal cooling device ops */
|
|
static struct thermal_cooling_device_ops const clock_cooling_ops = {
|
|
.get_max_state = clock_cooling_get_max_state,
|
|
.get_cur_state = clock_cooling_get_cur_state,
|
|
.set_cur_state = clock_cooling_set_cur_state,
|
|
};
|
|
|
|
/**
|
|
* clock_cooling_register - function to create clock cooling device.
|
|
* @dev: struct device pointer to the device used as clock cooling device.
|
|
* @clock_name: string containing the clock used as cooling mechanism.
|
|
*
|
|
* This interface function registers the clock cooling device with the name
|
|
* "thermal-clock-%x". The cooling device is based on clock frequencies.
|
|
* The struct device is assumed to be capable of DVFS transitions.
|
|
* The OPP layer is used to fetch and fill the available frequencies for
|
|
* the referred device. The ordered frequency table is used to control
|
|
* the clock cooling device cooling states and to limit clock transitions
|
|
* based on the cooling state requested by the thermal framework.
|
|
*
|
|
* Return: a valid struct thermal_cooling_device pointer on success,
|
|
* on failure, it returns a corresponding ERR_PTR().
|
|
*/
|
|
struct thermal_cooling_device *
|
|
clock_cooling_register(struct device *dev, const char *clock_name)
|
|
{
|
|
struct thermal_cooling_device *cdev;
|
|
struct clock_cooling_device *ccdev = NULL;
|
|
char dev_name[THERMAL_NAME_LENGTH];
|
|
int ret = 0;
|
|
|
|
ccdev = devm_kzalloc(dev, sizeof(*ccdev), GFP_KERNEL);
|
|
if (!ccdev)
|
|
return ERR_PTR(-ENOMEM);
|
|
|
|
mutex_init(&ccdev->lock);
|
|
ccdev->dev = dev;
|
|
ccdev->clk = devm_clk_get(dev, clock_name);
|
|
if (IS_ERR(ccdev->clk))
|
|
return ERR_CAST(ccdev->clk);
|
|
|
|
ret = clock_cooling_get_idr(&ccdev->id);
|
|
if (ret)
|
|
return ERR_PTR(-EINVAL);
|
|
|
|
snprintf(dev_name, sizeof(dev_name), "thermal-clock-%d", ccdev->id);
|
|
|
|
cdev = thermal_cooling_device_register(dev_name, ccdev,
|
|
&clock_cooling_ops);
|
|
if (IS_ERR(cdev)) {
|
|
release_idr(ccdev->id);
|
|
return ERR_PTR(-EINVAL);
|
|
}
|
|
ccdev->cdev = cdev;
|
|
ccdev->clk_rate_change_nb.notifier_call = clock_cooling_clock_notifier;
|
|
|
|
/* Assuming someone has already filled the opp table for this device */
|
|
ret = dev_pm_opp_init_cpufreq_table(dev, &ccdev->freq_table);
|
|
if (ret) {
|
|
release_idr(ccdev->id);
|
|
return ERR_PTR(ret);
|
|
}
|
|
ccdev->clock_state = 0;
|
|
ccdev->clock_val = clock_cooling_get_frequency(ccdev, 0);
|
|
|
|
clk_notifier_register(ccdev->clk, &ccdev->clk_rate_change_nb);
|
|
|
|
return cdev;
|
|
}
|
|
EXPORT_SYMBOL_GPL(clock_cooling_register);
|
|
|
|
/**
|
|
* clock_cooling_unregister - function to remove clock cooling device.
|
|
* @cdev: thermal cooling device pointer.
|
|
*
|
|
* This interface function unregisters the "thermal-clock-%x" cooling device.
|
|
*/
|
|
void clock_cooling_unregister(struct thermal_cooling_device *cdev)
|
|
{
|
|
struct clock_cooling_device *ccdev;
|
|
|
|
if (!cdev)
|
|
return;
|
|
|
|
ccdev = cdev->devdata;
|
|
|
|
clk_notifier_unregister(ccdev->clk, &ccdev->clk_rate_change_nb);
|
|
dev_pm_opp_free_cpufreq_table(ccdev->dev, &ccdev->freq_table);
|
|
|
|
thermal_cooling_device_unregister(ccdev->cdev);
|
|
release_idr(ccdev->id);
|
|
}
|
|
EXPORT_SYMBOL_GPL(clock_cooling_unregister);
|