linux/drivers/thermal/of-thermal.c
Srinivas Pandruvada 0e70f466fb thermal: Enhance thermal_zone_device_update for events
Added one additional parameter to thermal_zone_device_update() to provide
caller with an optional capability to specify reason.
Currently this event is used by user space governor to trigger different
processing based on event code. Also it saves an additional call to read
temperature when the event is received.
The following events are cuurently defined:
- Unspecified event
- New temperature sample
- Trip point violated
- Trip point changed
- thermal device up and down
- thermal device power capability changed

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
2016-09-27 14:35:21 +08:00

1070 lines
27 KiB
C

/*
* of-thermal.c - Generic Thermal Management device tree support.
*
* Copyright (C) 2013 Texas Instruments
* Copyright (C) 2013 Eduardo Valentin <eduardo.valentin@ti.com>
*
*
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*
* 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 <linux/thermal.h>
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/of_device.h>
#include <linux/of_platform.h>
#include <linux/err.h>
#include <linux/export.h>
#include <linux/string.h>
#include <linux/thermal.h>
#include "thermal_core.h"
/*** Private data structures to represent thermal device tree data ***/
/**
* struct __thermal_bind_param - a match between trip and cooling device
* @cooling_device: a pointer to identify the referred cooling device
* @trip_id: the trip point index
* @usage: the percentage (from 0 to 100) of cooling contribution
* @min: minimum cooling state used at this trip point
* @max: maximum cooling state used at this trip point
*/
struct __thermal_bind_params {
struct device_node *cooling_device;
unsigned int trip_id;
unsigned int usage;
unsigned long min;
unsigned long max;
};
/**
* struct __thermal_zone - internal representation of a thermal zone
* @mode: current thermal zone device mode (enabled/disabled)
* @passive_delay: polling interval while passive cooling is activated
* @polling_delay: zone polling interval
* @slope: slope of the temperature adjustment curve
* @offset: offset of the temperature adjustment curve
* @ntrips: number of trip points
* @trips: an array of trip points (0..ntrips - 1)
* @num_tbps: number of thermal bind params
* @tbps: an array of thermal bind params (0..num_tbps - 1)
* @sensor_data: sensor private data used while reading temperature and trend
* @ops: set of callbacks to handle the thermal zone based on DT
*/
struct __thermal_zone {
enum thermal_device_mode mode;
int passive_delay;
int polling_delay;
int slope;
int offset;
/* trip data */
int ntrips;
struct thermal_trip *trips;
/* cooling binding data */
int num_tbps;
struct __thermal_bind_params *tbps;
/* sensor interface */
void *sensor_data;
const struct thermal_zone_of_device_ops *ops;
};
/*** DT thermal zone device callbacks ***/
static int of_thermal_get_temp(struct thermal_zone_device *tz,
int *temp)
{
struct __thermal_zone *data = tz->devdata;
if (!data->ops->get_temp)
return -EINVAL;
return data->ops->get_temp(data->sensor_data, temp);
}
static int of_thermal_set_trips(struct thermal_zone_device *tz,
int low, int high)
{
struct __thermal_zone *data = tz->devdata;
if (!data->ops || !data->ops->set_trips)
return -EINVAL;
return data->ops->set_trips(data->sensor_data, low, high);
}
/**
* of_thermal_get_ntrips - function to export number of available trip
* points.
* @tz: pointer to a thermal zone
*
* This function is a globally visible wrapper to get number of trip points
* stored in the local struct __thermal_zone
*
* Return: number of available trip points, -ENODEV when data not available
*/
int of_thermal_get_ntrips(struct thermal_zone_device *tz)
{
struct __thermal_zone *data = tz->devdata;
if (!data || IS_ERR(data))
return -ENODEV;
return data->ntrips;
}
EXPORT_SYMBOL_GPL(of_thermal_get_ntrips);
/**
* of_thermal_is_trip_valid - function to check if trip point is valid
*
* @tz: pointer to a thermal zone
* @trip: trip point to evaluate
*
* This function is responsible for checking if passed trip point is valid
*
* Return: true if trip point is valid, false otherwise
*/
bool of_thermal_is_trip_valid(struct thermal_zone_device *tz, int trip)
{
struct __thermal_zone *data = tz->devdata;
if (!data || trip >= data->ntrips || trip < 0)
return false;
return true;
}
EXPORT_SYMBOL_GPL(of_thermal_is_trip_valid);
/**
* of_thermal_get_trip_points - function to get access to a globally exported
* trip points
*
* @tz: pointer to a thermal zone
*
* This function provides a pointer to trip points table
*
* Return: pointer to trip points table, NULL otherwise
*/
const struct thermal_trip *
of_thermal_get_trip_points(struct thermal_zone_device *tz)
{
struct __thermal_zone *data = tz->devdata;
if (!data)
return NULL;
return data->trips;
}
EXPORT_SYMBOL_GPL(of_thermal_get_trip_points);
/**
* of_thermal_set_emul_temp - function to set emulated temperature
*
* @tz: pointer to a thermal zone
* @temp: temperature to set
*
* This function gives the ability to set emulated value of temperature,
* which is handy for debugging
*
* Return: zero on success, error code otherwise
*/
static int of_thermal_set_emul_temp(struct thermal_zone_device *tz,
int temp)
{
struct __thermal_zone *data = tz->devdata;
return data->ops->set_emul_temp(data->sensor_data, temp);
}
static int of_thermal_get_trend(struct thermal_zone_device *tz, int trip,
enum thermal_trend *trend)
{
struct __thermal_zone *data = tz->devdata;
if (!data->ops->get_trend)
return -EINVAL;
return data->ops->get_trend(data->sensor_data, trip, trend);
}
static int of_thermal_bind(struct thermal_zone_device *thermal,
struct thermal_cooling_device *cdev)
{
struct __thermal_zone *data = thermal->devdata;
int i;
if (!data || IS_ERR(data))
return -ENODEV;
/* find where to bind */
for (i = 0; i < data->num_tbps; i++) {
struct __thermal_bind_params *tbp = data->tbps + i;
if (tbp->cooling_device == cdev->np) {
int ret;
ret = thermal_zone_bind_cooling_device(thermal,
tbp->trip_id, cdev,
tbp->max,
tbp->min,
tbp->usage);
if (ret)
return ret;
}
}
return 0;
}
static int of_thermal_unbind(struct thermal_zone_device *thermal,
struct thermal_cooling_device *cdev)
{
struct __thermal_zone *data = thermal->devdata;
int i;
if (!data || IS_ERR(data))
return -ENODEV;
/* find where to unbind */
for (i = 0; i < data->num_tbps; i++) {
struct __thermal_bind_params *tbp = data->tbps + i;
if (tbp->cooling_device == cdev->np) {
int ret;
ret = thermal_zone_unbind_cooling_device(thermal,
tbp->trip_id, cdev);
if (ret)
return ret;
}
}
return 0;
}
static int of_thermal_get_mode(struct thermal_zone_device *tz,
enum thermal_device_mode *mode)
{
struct __thermal_zone *data = tz->devdata;
*mode = data->mode;
return 0;
}
static int of_thermal_set_mode(struct thermal_zone_device *tz,
enum thermal_device_mode mode)
{
struct __thermal_zone *data = tz->devdata;
mutex_lock(&tz->lock);
if (mode == THERMAL_DEVICE_ENABLED)
tz->polling_delay = data->polling_delay;
else
tz->polling_delay = 0;
mutex_unlock(&tz->lock);
data->mode = mode;
thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
return 0;
}
static int of_thermal_get_trip_type(struct thermal_zone_device *tz, int trip,
enum thermal_trip_type *type)
{
struct __thermal_zone *data = tz->devdata;
if (trip >= data->ntrips || trip < 0)
return -EDOM;
*type = data->trips[trip].type;
return 0;
}
static int of_thermal_get_trip_temp(struct thermal_zone_device *tz, int trip,
int *temp)
{
struct __thermal_zone *data = tz->devdata;
if (trip >= data->ntrips || trip < 0)
return -EDOM;
*temp = data->trips[trip].temperature;
return 0;
}
static int of_thermal_set_trip_temp(struct thermal_zone_device *tz, int trip,
int temp)
{
struct __thermal_zone *data = tz->devdata;
if (trip >= data->ntrips || trip < 0)
return -EDOM;
if (data->ops->set_trip_temp) {
int ret;
ret = data->ops->set_trip_temp(data->sensor_data, trip, temp);
if (ret)
return ret;
}
/* thermal framework should take care of data->mask & (1 << trip) */
data->trips[trip].temperature = temp;
return 0;
}
static int of_thermal_get_trip_hyst(struct thermal_zone_device *tz, int trip,
int *hyst)
{
struct __thermal_zone *data = tz->devdata;
if (trip >= data->ntrips || trip < 0)
return -EDOM;
*hyst = data->trips[trip].hysteresis;
return 0;
}
static int of_thermal_set_trip_hyst(struct thermal_zone_device *tz, int trip,
int hyst)
{
struct __thermal_zone *data = tz->devdata;
if (trip >= data->ntrips || trip < 0)
return -EDOM;
/* thermal framework should take care of data->mask & (1 << trip) */
data->trips[trip].hysteresis = hyst;
return 0;
}
static int of_thermal_get_crit_temp(struct thermal_zone_device *tz,
int *temp)
{
struct __thermal_zone *data = tz->devdata;
int i;
for (i = 0; i < data->ntrips; i++)
if (data->trips[i].type == THERMAL_TRIP_CRITICAL) {
*temp = data->trips[i].temperature;
return 0;
}
return -EINVAL;
}
static struct thermal_zone_device_ops of_thermal_ops = {
.get_mode = of_thermal_get_mode,
.set_mode = of_thermal_set_mode,
.get_trip_type = of_thermal_get_trip_type,
.get_trip_temp = of_thermal_get_trip_temp,
.set_trip_temp = of_thermal_set_trip_temp,
.get_trip_hyst = of_thermal_get_trip_hyst,
.set_trip_hyst = of_thermal_set_trip_hyst,
.get_crit_temp = of_thermal_get_crit_temp,
.bind = of_thermal_bind,
.unbind = of_thermal_unbind,
};
/*** sensor API ***/
static struct thermal_zone_device *
thermal_zone_of_add_sensor(struct device_node *zone,
struct device_node *sensor, void *data,
const struct thermal_zone_of_device_ops *ops)
{
struct thermal_zone_device *tzd;
struct __thermal_zone *tz;
tzd = thermal_zone_get_zone_by_name(zone->name);
if (IS_ERR(tzd))
return ERR_PTR(-EPROBE_DEFER);
tz = tzd->devdata;
if (!ops)
return ERR_PTR(-EINVAL);
mutex_lock(&tzd->lock);
tz->ops = ops;
tz->sensor_data = data;
tzd->ops->get_temp = of_thermal_get_temp;
tzd->ops->get_trend = of_thermal_get_trend;
/*
* The thermal zone core will calculate the window if they have set the
* optional set_trips pointer.
*/
if (ops->set_trips)
tzd->ops->set_trips = of_thermal_set_trips;
if (ops->set_emul_temp)
tzd->ops->set_emul_temp = of_thermal_set_emul_temp;
mutex_unlock(&tzd->lock);
return tzd;
}
/**
* thermal_zone_of_sensor_register - registers a sensor to a DT thermal zone
* @dev: a valid struct device pointer of a sensor device. Must contain
* a valid .of_node, for the sensor node.
* @sensor_id: a sensor identifier, in case the sensor IP has more
* than one sensors
* @data: a private pointer (owned by the caller) that will be passed
* back, when a temperature reading is needed.
* @ops: struct thermal_zone_of_device_ops *. Must contain at least .get_temp.
*
* This function will search the list of thermal zones described in device
* tree and look for the zone that refer to the sensor device pointed by
* @dev->of_node as temperature providers. For the zone pointing to the
* sensor node, the sensor will be added to the DT thermal zone device.
*
* The thermal zone temperature is provided by the @get_temp function
* pointer. When called, it will have the private pointer @data back.
*
* The thermal zone temperature trend is provided by the @get_trend function
* pointer. When called, it will have the private pointer @data back.
*
* TODO:
* 01 - This function must enqueue the new sensor instead of using
* it as the only source of temperature values.
*
* 02 - There must be a way to match the sensor with all thermal zones
* that refer to it.
*
* Return: On success returns a valid struct thermal_zone_device,
* otherwise, it returns a corresponding ERR_PTR(). Caller must
* check the return value with help of IS_ERR() helper.
*/
struct thermal_zone_device *
thermal_zone_of_sensor_register(struct device *dev, int sensor_id, void *data,
const struct thermal_zone_of_device_ops *ops)
{
struct device_node *np, *child, *sensor_np;
struct thermal_zone_device *tzd = ERR_PTR(-ENODEV);
np = of_find_node_by_name(NULL, "thermal-zones");
if (!np)
return ERR_PTR(-ENODEV);
if (!dev || !dev->of_node) {
of_node_put(np);
return ERR_PTR(-EINVAL);
}
sensor_np = of_node_get(dev->of_node);
for_each_available_child_of_node(np, child) {
struct of_phandle_args sensor_specs;
int ret, id;
/* For now, thermal framework supports only 1 sensor per zone */
ret = of_parse_phandle_with_args(child, "thermal-sensors",
"#thermal-sensor-cells",
0, &sensor_specs);
if (ret)
continue;
if (sensor_specs.args_count >= 1) {
id = sensor_specs.args[0];
WARN(sensor_specs.args_count > 1,
"%s: too many cells in sensor specifier %d\n",
sensor_specs.np->name, sensor_specs.args_count);
} else {
id = 0;
}
if (sensor_specs.np == sensor_np && id == sensor_id) {
tzd = thermal_zone_of_add_sensor(child, sensor_np,
data, ops);
if (!IS_ERR(tzd))
tzd->ops->set_mode(tzd, THERMAL_DEVICE_ENABLED);
of_node_put(sensor_specs.np);
of_node_put(child);
goto exit;
}
of_node_put(sensor_specs.np);
}
exit:
of_node_put(sensor_np);
of_node_put(np);
return tzd;
}
EXPORT_SYMBOL_GPL(thermal_zone_of_sensor_register);
/**
* thermal_zone_of_sensor_unregister - unregisters a sensor from a DT thermal zone
* @dev: a valid struct device pointer of a sensor device. Must contain
* a valid .of_node, for the sensor node.
* @tzd: a pointer to struct thermal_zone_device where the sensor is registered.
*
* This function removes the sensor callbacks and private data from the
* thermal zone device registered with thermal_zone_of_sensor_register()
* API. It will also silent the zone by remove the .get_temp() and .get_trend()
* thermal zone device callbacks.
*
* TODO: When the support to several sensors per zone is added, this
* function must search the sensor list based on @dev parameter.
*
*/
void thermal_zone_of_sensor_unregister(struct device *dev,
struct thermal_zone_device *tzd)
{
struct __thermal_zone *tz;
if (!dev || !tzd || !tzd->devdata)
return;
tz = tzd->devdata;
/* no __thermal_zone, nothing to be done */
if (!tz)
return;
mutex_lock(&tzd->lock);
tzd->ops->get_temp = NULL;
tzd->ops->get_trend = NULL;
tzd->ops->set_emul_temp = NULL;
tz->ops = NULL;
tz->sensor_data = NULL;
mutex_unlock(&tzd->lock);
}
EXPORT_SYMBOL_GPL(thermal_zone_of_sensor_unregister);
static void devm_thermal_zone_of_sensor_release(struct device *dev, void *res)
{
thermal_zone_of_sensor_unregister(dev,
*(struct thermal_zone_device **)res);
}
static int devm_thermal_zone_of_sensor_match(struct device *dev, void *res,
void *data)
{
struct thermal_zone_device **r = res;
if (WARN_ON(!r || !*r))
return 0;
return *r == data;
}
/**
* devm_thermal_zone_of_sensor_register - Resource managed version of
* thermal_zone_of_sensor_register()
* @dev: a valid struct device pointer of a sensor device. Must contain
* a valid .of_node, for the sensor node.
* @sensor_id: a sensor identifier, in case the sensor IP has more
* than one sensors
* @data: a private pointer (owned by the caller) that will be passed
* back, when a temperature reading is needed.
* @ops: struct thermal_zone_of_device_ops *. Must contain at least .get_temp.
*
* Refer thermal_zone_of_sensor_register() for more details.
*
* Return: On success returns a valid struct thermal_zone_device,
* otherwise, it returns a corresponding ERR_PTR(). Caller must
* check the return value with help of IS_ERR() helper.
* Registered thermal_zone_device device will automatically be
* released when device is unbounded.
*/
struct thermal_zone_device *devm_thermal_zone_of_sensor_register(
struct device *dev, int sensor_id,
void *data, const struct thermal_zone_of_device_ops *ops)
{
struct thermal_zone_device **ptr, *tzd;
ptr = devres_alloc(devm_thermal_zone_of_sensor_release, sizeof(*ptr),
GFP_KERNEL);
if (!ptr)
return ERR_PTR(-ENOMEM);
tzd = thermal_zone_of_sensor_register(dev, sensor_id, data, ops);
if (IS_ERR(tzd)) {
devres_free(ptr);
return tzd;
}
*ptr = tzd;
devres_add(dev, ptr);
return tzd;
}
EXPORT_SYMBOL_GPL(devm_thermal_zone_of_sensor_register);
/**
* devm_thermal_zone_of_sensor_unregister - Resource managed version of
* thermal_zone_of_sensor_unregister().
* @dev: Device for which which resource was allocated.
* @tzd: a pointer to struct thermal_zone_device where the sensor is registered.
*
* This function removes the sensor callbacks and private data from the
* thermal zone device registered with devm_thermal_zone_of_sensor_register()
* API. It will also silent the zone by remove the .get_temp() and .get_trend()
* thermal zone device callbacks.
* Normally this function will not need to be called and the resource
* management code will ensure that the resource is freed.
*/
void devm_thermal_zone_of_sensor_unregister(struct device *dev,
struct thermal_zone_device *tzd)
{
WARN_ON(devres_release(dev, devm_thermal_zone_of_sensor_release,
devm_thermal_zone_of_sensor_match, tzd));
}
EXPORT_SYMBOL_GPL(devm_thermal_zone_of_sensor_unregister);
/*** functions parsing device tree nodes ***/
/**
* thermal_of_populate_bind_params - parse and fill cooling map data
* @np: DT node containing a cooling-map node
* @__tbp: data structure to be filled with cooling map info
* @trips: array of thermal zone trip points
* @ntrips: number of trip points inside trips.
*
* This function parses a cooling-map type of node represented by
* @np parameter and fills the read data into @__tbp data structure.
* It needs the already parsed array of trip points of the thermal zone
* in consideration.
*
* Return: 0 on success, proper error code otherwise
*/
static int thermal_of_populate_bind_params(struct device_node *np,
struct __thermal_bind_params *__tbp,
struct thermal_trip *trips,
int ntrips)
{
struct of_phandle_args cooling_spec;
struct device_node *trip;
int ret, i;
u32 prop;
/* Default weight. Usage is optional */
__tbp->usage = THERMAL_WEIGHT_DEFAULT;
ret = of_property_read_u32(np, "contribution", &prop);
if (ret == 0)
__tbp->usage = prop;
trip = of_parse_phandle(np, "trip", 0);
if (!trip) {
pr_err("missing trip property\n");
return -ENODEV;
}
/* match using device_node */
for (i = 0; i < ntrips; i++)
if (trip == trips[i].np) {
__tbp->trip_id = i;
break;
}
if (i == ntrips) {
ret = -ENODEV;
goto end;
}
ret = of_parse_phandle_with_args(np, "cooling-device", "#cooling-cells",
0, &cooling_spec);
if (ret < 0) {
pr_err("missing cooling_device property\n");
goto end;
}
__tbp->cooling_device = cooling_spec.np;
if (cooling_spec.args_count >= 2) { /* at least min and max */
__tbp->min = cooling_spec.args[0];
__tbp->max = cooling_spec.args[1];
} else {
pr_err("wrong reference to cooling device, missing limits\n");
}
end:
of_node_put(trip);
return ret;
}
/**
* It maps 'enum thermal_trip_type' found in include/linux/thermal.h
* into the device tree binding of 'trip', property type.
*/
static const char * const trip_types[] = {
[THERMAL_TRIP_ACTIVE] = "active",
[THERMAL_TRIP_PASSIVE] = "passive",
[THERMAL_TRIP_HOT] = "hot",
[THERMAL_TRIP_CRITICAL] = "critical",
};
/**
* thermal_of_get_trip_type - Get phy mode for given device_node
* @np: Pointer to the given device_node
* @type: Pointer to resulting trip type
*
* The function gets trip type string from property 'type',
* and store its index in trip_types table in @type,
*
* Return: 0 on success, or errno in error case.
*/
static int thermal_of_get_trip_type(struct device_node *np,
enum thermal_trip_type *type)
{
const char *t;
int err, i;
err = of_property_read_string(np, "type", &t);
if (err < 0)
return err;
for (i = 0; i < ARRAY_SIZE(trip_types); i++)
if (!strcasecmp(t, trip_types[i])) {
*type = i;
return 0;
}
return -ENODEV;
}
/**
* thermal_of_populate_trip - parse and fill one trip point data
* @np: DT node containing a trip point node
* @trip: trip point data structure to be filled up
*
* This function parses a trip point type of node represented by
* @np parameter and fills the read data into @trip data structure.
*
* Return: 0 on success, proper error code otherwise
*/
static int thermal_of_populate_trip(struct device_node *np,
struct thermal_trip *trip)
{
int prop;
int ret;
ret = of_property_read_u32(np, "temperature", &prop);
if (ret < 0) {
pr_err("missing temperature property\n");
return ret;
}
trip->temperature = prop;
ret = of_property_read_u32(np, "hysteresis", &prop);
if (ret < 0) {
pr_err("missing hysteresis property\n");
return ret;
}
trip->hysteresis = prop;
ret = thermal_of_get_trip_type(np, &trip->type);
if (ret < 0) {
pr_err("wrong trip type property\n");
return ret;
}
/* Required for cooling map matching */
trip->np = np;
of_node_get(np);
return 0;
}
/**
* thermal_of_build_thermal_zone - parse and fill one thermal zone data
* @np: DT node containing a thermal zone node
*
* This function parses a thermal zone type of node represented by
* @np parameter and fills the read data into a __thermal_zone data structure
* and return this pointer.
*
* TODO: Missing properties to parse: thermal-sensor-names
*
* Return: On success returns a valid struct __thermal_zone,
* otherwise, it returns a corresponding ERR_PTR(). Caller must
* check the return value with help of IS_ERR() helper.
*/
static struct __thermal_zone
__init *thermal_of_build_thermal_zone(struct device_node *np)
{
struct device_node *child = NULL, *gchild;
struct __thermal_zone *tz;
int ret, i;
u32 prop, coef[2];
if (!np) {
pr_err("no thermal zone np\n");
return ERR_PTR(-EINVAL);
}
tz = kzalloc(sizeof(*tz), GFP_KERNEL);
if (!tz)
return ERR_PTR(-ENOMEM);
ret = of_property_read_u32(np, "polling-delay-passive", &prop);
if (ret < 0) {
pr_err("missing polling-delay-passive property\n");
goto free_tz;
}
tz->passive_delay = prop;
ret = of_property_read_u32(np, "polling-delay", &prop);
if (ret < 0) {
pr_err("missing polling-delay property\n");
goto free_tz;
}
tz->polling_delay = prop;
/*
* REVIST: for now, the thermal framework supports only
* one sensor per thermal zone. Thus, we are considering
* only the first two values as slope and offset.
*/
ret = of_property_read_u32_array(np, "coefficients", coef, 2);
if (ret == 0) {
tz->slope = coef[0];
tz->offset = coef[1];
} else {
tz->slope = 1;
tz->offset = 0;
}
/* trips */
child = of_get_child_by_name(np, "trips");
/* No trips provided */
if (!child)
goto finish;
tz->ntrips = of_get_child_count(child);
if (tz->ntrips == 0) /* must have at least one child */
goto finish;
tz->trips = kzalloc(tz->ntrips * sizeof(*tz->trips), GFP_KERNEL);
if (!tz->trips) {
ret = -ENOMEM;
goto free_tz;
}
i = 0;
for_each_child_of_node(child, gchild) {
ret = thermal_of_populate_trip(gchild, &tz->trips[i++]);
if (ret)
goto free_trips;
}
of_node_put(child);
/* cooling-maps */
child = of_get_child_by_name(np, "cooling-maps");
/* cooling-maps not provided */
if (!child)
goto finish;
tz->num_tbps = of_get_child_count(child);
if (tz->num_tbps == 0)
goto finish;
tz->tbps = kzalloc(tz->num_tbps * sizeof(*tz->tbps), GFP_KERNEL);
if (!tz->tbps) {
ret = -ENOMEM;
goto free_trips;
}
i = 0;
for_each_child_of_node(child, gchild) {
ret = thermal_of_populate_bind_params(gchild, &tz->tbps[i++],
tz->trips, tz->ntrips);
if (ret)
goto free_tbps;
}
finish:
of_node_put(child);
tz->mode = THERMAL_DEVICE_DISABLED;
return tz;
free_tbps:
for (i = i - 1; i >= 0; i--)
of_node_put(tz->tbps[i].cooling_device);
kfree(tz->tbps);
free_trips:
for (i = 0; i < tz->ntrips; i++)
of_node_put(tz->trips[i].np);
kfree(tz->trips);
of_node_put(gchild);
free_tz:
kfree(tz);
of_node_put(child);
return ERR_PTR(ret);
}
static inline void of_thermal_free_zone(struct __thermal_zone *tz)
{
int i;
for (i = 0; i < tz->num_tbps; i++)
of_node_put(tz->tbps[i].cooling_device);
kfree(tz->tbps);
for (i = 0; i < tz->ntrips; i++)
of_node_put(tz->trips[i].np);
kfree(tz->trips);
kfree(tz);
}
/**
* of_parse_thermal_zones - parse device tree thermal data
*
* Initialization function that can be called by machine initialization
* code to parse thermal data and populate the thermal framework
* with hardware thermal zones info. This function only parses thermal zones.
* Cooling devices and sensor devices nodes are supposed to be parsed
* by their respective drivers.
*
* Return: 0 on success, proper error code otherwise
*
*/
int __init of_parse_thermal_zones(void)
{
struct device_node *np, *child;
struct __thermal_zone *tz;
struct thermal_zone_device_ops *ops;
np = of_find_node_by_name(NULL, "thermal-zones");
if (!np) {
pr_debug("unable to find thermal zones\n");
return 0; /* Run successfully on systems without thermal DT */
}
for_each_available_child_of_node(np, child) {
struct thermal_zone_device *zone;
struct thermal_zone_params *tzp;
int i, mask = 0;
u32 prop;
tz = thermal_of_build_thermal_zone(child);
if (IS_ERR(tz)) {
pr_err("failed to build thermal zone %s: %ld\n",
child->name,
PTR_ERR(tz));
continue;
}
ops = kmemdup(&of_thermal_ops, sizeof(*ops), GFP_KERNEL);
if (!ops)
goto exit_free;
tzp = kzalloc(sizeof(*tzp), GFP_KERNEL);
if (!tzp) {
kfree(ops);
goto exit_free;
}
/* No hwmon because there might be hwmon drivers registering */
tzp->no_hwmon = true;
if (!of_property_read_u32(child, "sustainable-power", &prop))
tzp->sustainable_power = prop;
for (i = 0; i < tz->ntrips; i++)
mask |= 1 << i;
/* these two are left for temperature drivers to use */
tzp->slope = tz->slope;
tzp->offset = tz->offset;
zone = thermal_zone_device_register(child->name, tz->ntrips,
mask, tz,
ops, tzp,
tz->passive_delay,
tz->polling_delay);
if (IS_ERR(zone)) {
pr_err("Failed to build %s zone %ld\n", child->name,
PTR_ERR(zone));
kfree(tzp);
kfree(ops);
of_thermal_free_zone(tz);
/* attempting to build remaining zones still */
}
}
of_node_put(np);
return 0;
exit_free:
of_node_put(child);
of_node_put(np);
of_thermal_free_zone(tz);
/* no memory available, so free what we have built */
of_thermal_destroy_zones();
return -ENOMEM;
}
/**
* of_thermal_destroy_zones - remove all zones parsed and allocated resources
*
* Finds all zones parsed and added to the thermal framework and remove them
* from the system, together with their resources.
*
*/
void of_thermal_destroy_zones(void)
{
struct device_node *np, *child;
np = of_find_node_by_name(NULL, "thermal-zones");
if (!np) {
pr_debug("unable to find thermal zones\n");
return;
}
for_each_available_child_of_node(np, child) {
struct thermal_zone_device *zone;
zone = thermal_zone_get_zone_by_name(child->name);
if (IS_ERR(zone))
continue;
thermal_zone_device_unregister(zone);
kfree(zone->tzp);
kfree(zone->ops);
of_thermal_free_zone(zone->devdata);
}
of_node_put(np);
}