| // SPDX-License-Identifier: GPL-2.0 |
| /* |
| * of-thermal.c - Generic Thermal Management device tree support. |
| * |
| * Copyright (C) 2013 Texas Instruments |
| * Copyright (C) 2013 Eduardo Valentin <eduardo.valentin@ti.com> |
| */ |
| |
| #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
| |
| #include <linux/err.h> |
| #include <linux/export.h> |
| #include <linux/of.h> |
| #include <linux/slab.h> |
| #include <linux/thermal.h> |
| #include <linux/types.h> |
| #include <linux/string.h> |
| |
| #include "thermal_core.h" |
| |
| /*** functions parsing device tree nodes ***/ |
| |
| /* |
| * 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; |
| } |
| |
| 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; |
| } |
| |
| trip->flags = THERMAL_TRIP_FLAG_RW_TEMP; |
| |
| trip->priv = np; |
| |
| return 0; |
| } |
| |
| static struct thermal_trip *thermal_of_trips_init(struct device_node *np, int *ntrips) |
| { |
| struct thermal_trip *tt; |
| struct device_node *trips; |
| int ret, count; |
| |
| *ntrips = 0; |
| |
| trips = of_get_child_by_name(np, "trips"); |
| if (!trips) |
| return NULL; |
| |
| count = of_get_child_count(trips); |
| if (!count) |
| return NULL; |
| |
| tt = kzalloc(sizeof(*tt) * count, GFP_KERNEL); |
| if (!tt) { |
| ret = -ENOMEM; |
| goto out_of_node_put; |
| } |
| |
| *ntrips = count; |
| |
| count = 0; |
| for_each_child_of_node_scoped(trips, trip) { |
| ret = thermal_of_populate_trip(trip, &tt[count++]); |
| if (ret) |
| goto out_kfree; |
| } |
| |
| of_node_put(trips); |
| |
| return tt; |
| |
| out_kfree: |
| kfree(tt); |
| out_of_node_put: |
| of_node_put(trips); |
| |
| return ERR_PTR(ret); |
| } |
| |
| static struct device_node *of_thermal_zone_find(struct device_node *sensor, int id) |
| { |
| struct device_node *np, *tz; |
| struct of_phandle_args sensor_specs; |
| |
| np = of_find_node_by_name(NULL, "thermal-zones"); |
| if (!np) { |
| pr_debug("No thermal zones description\n"); |
| return ERR_PTR(-ENODEV); |
| } |
| |
| /* |
| * Search for each thermal zone, a defined sensor |
| * corresponding to the one passed as parameter |
| */ |
| for_each_available_child_of_node_scoped(np, child) { |
| |
| int count, i; |
| |
| count = of_count_phandle_with_args(child, "thermal-sensors", |
| "#thermal-sensor-cells"); |
| if (count <= 0) { |
| pr_err("%pOFn: missing thermal sensor\n", child); |
| tz = ERR_PTR(-EINVAL); |
| goto out; |
| } |
| |
| for (i = 0; i < count; i++) { |
| |
| int ret; |
| |
| ret = of_parse_phandle_with_args(child, "thermal-sensors", |
| "#thermal-sensor-cells", |
| i, &sensor_specs); |
| if (ret < 0) { |
| pr_err("%pOFn: Failed to read thermal-sensors cells: %d\n", child, ret); |
| tz = ERR_PTR(ret); |
| goto out; |
| } |
| |
| if ((sensor == sensor_specs.np) && id == (sensor_specs.args_count ? |
| sensor_specs.args[0] : 0)) { |
| pr_debug("sensor %pOFn id=%d belongs to %pOFn\n", sensor, id, child); |
| tz = no_free_ptr(child); |
| goto out; |
| } |
| } |
| } |
| tz = ERR_PTR(-ENODEV); |
| out: |
| of_node_put(np); |
| return tz; |
| } |
| |
| static int thermal_of_monitor_init(struct device_node *np, int *delay, int *pdelay) |
| { |
| int ret; |
| |
| ret = of_property_read_u32(np, "polling-delay-passive", pdelay); |
| if (ret == -EINVAL) { |
| *pdelay = 0; |
| } else if (ret < 0) { |
| pr_err("%pOFn: Couldn't get polling-delay-passive: %d\n", np, ret); |
| return ret; |
| } |
| |
| ret = of_property_read_u32(np, "polling-delay", delay); |
| if (ret == -EINVAL) { |
| *delay = 0; |
| } else if (ret < 0) { |
| pr_err("%pOFn: Couldn't get polling-delay: %d\n", np, ret); |
| return ret; |
| } |
| |
| return 0; |
| } |
| |
| static void thermal_of_parameters_init(struct device_node *np, |
| struct thermal_zone_params *tzp) |
| { |
| int coef[2]; |
| int ncoef = ARRAY_SIZE(coef); |
| int prop, ret; |
| |
| tzp->no_hwmon = true; |
| |
| if (!of_property_read_u32(np, "sustainable-power", &prop)) |
| tzp->sustainable_power = prop; |
| |
| /* |
| * 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, ncoef); |
| if (ret) { |
| coef[0] = 1; |
| coef[1] = 0; |
| } |
| |
| tzp->slope = coef[0]; |
| tzp->offset = coef[1]; |
| } |
| |
| static struct device_node *thermal_of_zone_get_by_name(struct thermal_zone_device *tz) |
| { |
| struct device_node *np, *tz_np; |
| |
| np = of_find_node_by_name(NULL, "thermal-zones"); |
| if (!np) |
| return ERR_PTR(-ENODEV); |
| |
| tz_np = of_get_child_by_name(np, tz->type); |
| |
| of_node_put(np); |
| |
| if (!tz_np) |
| return ERR_PTR(-ENODEV); |
| |
| return tz_np; |
| } |
| |
| static bool thermal_of_get_cooling_spec(struct device_node *map_np, int index, |
| struct thermal_cooling_device *cdev, |
| struct cooling_spec *c) |
| { |
| struct of_phandle_args cooling_spec; |
| int ret, weight = THERMAL_WEIGHT_DEFAULT; |
| |
| of_property_read_u32(map_np, "contribution", &weight); |
| |
| ret = of_parse_phandle_with_args(map_np, "cooling-device", "#cooling-cells", |
| index, &cooling_spec); |
| |
| if (ret < 0) { |
| pr_err("Invalid cooling-device entry\n"); |
| return false; |
| } |
| |
| of_node_put(cooling_spec.np); |
| |
| if (cooling_spec.args_count < 2) { |
| pr_err("wrong reference to cooling device, missing limits\n"); |
| return false; |
| } |
| |
| if (cooling_spec.np != cdev->np) |
| return false; |
| |
| c->lower = cooling_spec.args[0]; |
| c->upper = cooling_spec.args[1]; |
| c->weight = weight; |
| |
| return true; |
| } |
| |
| static bool thermal_of_should_bind(struct thermal_zone_device *tz, |
| const struct thermal_trip *trip, |
| struct thermal_cooling_device *cdev, |
| struct cooling_spec *c) |
| { |
| struct device_node *tz_np, *cm_np, *child; |
| bool result = false; |
| |
| tz_np = thermal_of_zone_get_by_name(tz); |
| if (IS_ERR(tz_np)) { |
| pr_err("Failed to get node tz by name\n"); |
| return false; |
| } |
| |
| cm_np = of_get_child_by_name(tz_np, "cooling-maps"); |
| if (!cm_np) |
| goto out; |
| |
| /* Look up the trip and the cdev in the cooling maps. */ |
| for_each_child_of_node(cm_np, child) { |
| struct device_node *tr_np; |
| int count, i; |
| |
| tr_np = of_parse_phandle(child, "trip", 0); |
| if (tr_np != trip->priv) |
| continue; |
| |
| /* The trip has been found, look up the cdev. */ |
| count = of_count_phandle_with_args(child, "cooling-device", "#cooling-cells"); |
| if (count <= 0) |
| pr_err("Add a cooling_device property with at least one device\n"); |
| |
| for (i = 0; i < count; i++) { |
| result = thermal_of_get_cooling_spec(child, i, cdev, c); |
| if (result) |
| break; |
| } |
| |
| of_node_put(child); |
| break; |
| } |
| |
| of_node_put(cm_np); |
| out: |
| of_node_put(tz_np); |
| |
| return result; |
| } |
| |
| /** |
| * thermal_of_zone_unregister - Cleanup the specific allocated ressources |
| * |
| * This function disables the thermal zone and frees the different |
| * ressources allocated specific to the thermal OF. |
| * |
| * @tz: a pointer to the thermal zone structure |
| */ |
| static void thermal_of_zone_unregister(struct thermal_zone_device *tz) |
| { |
| thermal_zone_device_disable(tz); |
| thermal_zone_device_unregister(tz); |
| } |
| |
| /** |
| * thermal_of_zone_register - Register a thermal zone with device node |
| * sensor |
| * |
| * The thermal_of_zone_register() parses a device tree given a device |
| * node sensor and identifier. It searches for the thermal zone |
| * associated to the couple sensor/id and retrieves all the thermal |
| * zone properties and registers new thermal zone with those |
| * properties. |
| * |
| * @sensor: A device node pointer corresponding to the sensor in the device tree |
| * @id: An integer as sensor identifier |
| * @data: A private data to be stored in the thermal zone dedicated private area |
| * @ops: A set of thermal sensor ops |
| * |
| * Return: a valid thermal zone structure pointer on success. |
| * - EINVAL: if the device tree thermal description is malformed |
| * - ENOMEM: if one structure can not be allocated |
| * - Other negative errors are returned by the underlying called functions |
| */ |
| static struct thermal_zone_device *thermal_of_zone_register(struct device_node *sensor, int id, void *data, |
| const struct thermal_zone_device_ops *ops) |
| { |
| struct thermal_zone_device_ops of_ops = *ops; |
| struct thermal_zone_device *tz; |
| struct thermal_trip *trips; |
| struct thermal_zone_params tzp = {}; |
| struct device_node *np; |
| const char *action; |
| int delay, pdelay; |
| int ntrips; |
| int ret; |
| |
| np = of_thermal_zone_find(sensor, id); |
| if (IS_ERR(np)) { |
| if (PTR_ERR(np) != -ENODEV) |
| pr_err("Failed to find thermal zone for %pOFn id=%d\n", sensor, id); |
| return ERR_CAST(np); |
| } |
| |
| trips = thermal_of_trips_init(np, &ntrips); |
| if (IS_ERR(trips)) { |
| pr_err("Failed to parse trip points for %pOFn id=%d\n", sensor, id); |
| ret = PTR_ERR(trips); |
| goto out_of_node_put; |
| } |
| |
| if (!trips) |
| pr_info("No trip points found for %pOFn id=%d\n", sensor, id); |
| |
| ret = thermal_of_monitor_init(np, &delay, &pdelay); |
| if (ret) { |
| pr_err("Failed to initialize monitoring delays from %pOFn\n", np); |
| goto out_kfree_trips; |
| } |
| |
| thermal_of_parameters_init(np, &tzp); |
| |
| of_ops.should_bind = thermal_of_should_bind; |
| |
| ret = of_property_read_string(np, "critical-action", &action); |
| if (!ret) |
| if (!of_ops.critical && !strcasecmp(action, "reboot")) |
| of_ops.critical = thermal_zone_device_critical_reboot; |
| |
| tz = thermal_zone_device_register_with_trips(np->name, trips, ntrips, |
| data, &of_ops, &tzp, |
| pdelay, delay); |
| if (IS_ERR(tz)) { |
| ret = PTR_ERR(tz); |
| pr_err("Failed to register thermal zone %pOFn: %d\n", np, ret); |
| goto out_kfree_trips; |
| } |
| |
| of_node_put(np); |
| kfree(trips); |
| |
| ret = thermal_zone_device_enable(tz); |
| if (ret) { |
| pr_err("Failed to enabled thermal zone '%s', id=%d: %d\n", |
| tz->type, tz->id, ret); |
| thermal_of_zone_unregister(tz); |
| return ERR_PTR(ret); |
| } |
| |
| return tz; |
| |
| out_kfree_trips: |
| kfree(trips); |
| out_of_node_put: |
| of_node_put(np); |
| |
| return ERR_PTR(ret); |
| } |
| |
| static void devm_thermal_of_zone_release(struct device *dev, void *res) |
| { |
| thermal_of_zone_unregister(*(struct thermal_zone_device **)res); |
| } |
| |
| static int devm_thermal_of_zone_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_of_zone_register - register a thermal tied with the sensor life cycle |
| * |
| * This function is the device version of the thermal_of_zone_register() function. |
| * |
| * @dev: a device structure pointer to sensor to be tied with the thermal zone OF life cycle |
| * @sensor_id: the sensor identifier |
| * @data: a pointer to a private data to be stored in the thermal zone 'devdata' field |
| * @ops: a pointer to the ops structure associated with the sensor |
| */ |
| struct thermal_zone_device *devm_thermal_of_zone_register(struct device *dev, int sensor_id, void *data, |
| const struct thermal_zone_device_ops *ops) |
| { |
| struct thermal_zone_device **ptr, *tzd; |
| |
| ptr = devres_alloc(devm_thermal_of_zone_release, sizeof(*ptr), |
| GFP_KERNEL); |
| if (!ptr) |
| return ERR_PTR(-ENOMEM); |
| |
| tzd = thermal_of_zone_register(dev->of_node, 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_of_zone_register); |
| |
| /** |
| * devm_thermal_of_zone_unregister - Resource managed version of |
| * thermal_of_zone_unregister(). |
| * @dev: Device for which which resource was allocated. |
| * @tz: a pointer to struct thermal_zone 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_of_zone_unregister(struct device *dev, struct thermal_zone_device *tz) |
| { |
| WARN_ON(devres_release(dev, devm_thermal_of_zone_release, |
| devm_thermal_of_zone_match, tz)); |
| } |
| EXPORT_SYMBOL_GPL(devm_thermal_of_zone_unregister); |