diff options
Diffstat (limited to 'drivers/thermal/thermal_of.c')
| -rw-r--r-- | drivers/thermal/thermal_of.c | 742 |
1 files changed, 742 insertions, 0 deletions
diff --git a/drivers/thermal/thermal_of.c b/drivers/thermal/thermal_of.c new file mode 100644 index 000000000..4104743db --- /dev/null +++ b/drivers/thermal/thermal_of.c @@ -0,0 +1,742 @@ +// 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_device.h> +#include <linux/of_platform.h> +#include <linux/slab.h> +#include <linux/thermal.h> +#include <linux/types.h> +#include <linux/string.h> + +#include "thermal_core.h" + +/** + * 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) +{ + return tz->num_trips; +} +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) +{ + if (trip >= tz->num_trips || 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) +{ + return tz->trips; +} +EXPORT_SYMBOL_GPL(of_thermal_get_trip_points); + +static int of_thermal_get_trip_type(struct thermal_zone_device *tz, int trip, + enum thermal_trip_type *type) +{ + if (trip >= tz->num_trips || trip < 0) + return -EDOM; + + *type = tz->trips[trip].type; + + return 0; +} + +static int of_thermal_get_trip_temp(struct thermal_zone_device *tz, int trip, + int *temp) +{ + if (trip >= tz->num_trips || trip < 0) + return -EDOM; + + *temp = tz->trips[trip].temperature; + + return 0; +} + +static int of_thermal_get_trip_hyst(struct thermal_zone_device *tz, int trip, + int *hyst) +{ + if (trip >= tz->num_trips || trip < 0) + return -EDOM; + + *hyst = tz->trips[trip].hysteresis; + + return 0; +} + +static int of_thermal_set_trip_hyst(struct thermal_zone_device *tz, int trip, + int hyst) +{ + if (trip >= tz->num_trips || trip < 0) + return -EDOM; + + /* thermal framework should take care of data->mask & (1 << trip) */ + tz->trips[trip].hysteresis = hyst; + + return 0; +} + +static int of_thermal_get_crit_temp(struct thermal_zone_device *tz, + int *temp) +{ + int i; + + for (i = 0; i < tz->num_trips; i++) + if (tz->trips[i].type == THERMAL_TRIP_CRITICAL) { + *temp = tz->trips[i].temperature; + return 0; + } + + return -EINVAL; +} + +/*** functions parsing device tree nodes ***/ + +static int of_find_trip_id(struct device_node *np, struct device_node *trip) +{ + struct device_node *trips; + struct device_node *t; + int i = 0; + + trips = of_get_child_by_name(np, "trips"); + if (!trips) { + pr_err("Failed to find 'trips' node\n"); + return -EINVAL; + } + + /* + * Find the trip id point associated with the cooling device map + */ + for_each_child_of_node(trips, t) { + + if (t == trip) { + of_node_put(t); + goto out; + } + i++; + } + + i = -ENXIO; +out: + of_node_put(trips); + + return i; +} + +/* + * 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; + } + + return 0; +} + +static struct thermal_trip *thermal_of_trips_init(struct device_node *np, int *ntrips) +{ + struct thermal_trip *tt; + struct device_node *trips, *trip; + int ret, count; + + trips = of_get_child_by_name(np, "trips"); + if (!trips) { + pr_err("Failed to find 'trips' node\n"); + return ERR_PTR(-EINVAL); + } + + count = of_get_child_count(trips); + if (!count) { + pr_err("No trip point defined\n"); + ret = -EINVAL; + goto out_of_node_put; + } + + 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(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); + *ntrips = 0; +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(np, tz) { + + int count, i; + + count = of_count_phandle_with_args(tz, "thermal-sensors", + "#thermal-sensor-cells"); + if (count <= 0) { + pr_err("%pOFn: missing thermal sensor\n", tz); + tz = ERR_PTR(-EINVAL); + goto out; + } + + for (i = 0; i < count; i++) { + + int ret; + + ret = of_parse_phandle_with_args(tz, "thermal-sensors", + "#thermal-sensor-cells", + i, &sensor_specs); + if (ret < 0) { + pr_err("%pOFn: Failed to read thermal-sensors cells: %d\n", tz, 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, tz); + 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 < 0) { + pr_err("%pOFn: missing polling-delay-passive property\n", np); + return ret; + } + + ret = of_property_read_u32(np, "polling-delay", delay); + if (ret < 0) { + pr_err("%pOFn: missing polling-delay property\n", np); + return ret; + } + + return 0; +} + +static struct thermal_zone_params *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 = kzalloc(sizeof(*tzp), GFP_KERNEL); + if (!tzp) + return ERR_PTR(-ENOMEM); + + 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]; + + return tzp; +} + +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 int __thermal_of_unbind(struct device_node *map_np, int index, int trip_id, + struct thermal_zone_device *tz, struct thermal_cooling_device *cdev) +{ + struct of_phandle_args cooling_spec; + int ret; + + 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 ret; + } + + of_node_put(cooling_spec.np); + + if (cooling_spec.args_count < 2) { + pr_err("wrong reference to cooling device, missing limits\n"); + return -EINVAL; + } + + if (cooling_spec.np != cdev->np) + return 0; + + ret = thermal_zone_unbind_cooling_device(tz, trip_id, cdev); + if (ret) + pr_err("Failed to unbind '%s' with '%s': %d\n", tz->type, cdev->type, ret); + + return ret; +} + +static int __thermal_of_bind(struct device_node *map_np, int index, int trip_id, + struct thermal_zone_device *tz, struct thermal_cooling_device *cdev) +{ + 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 ret; + } + + of_node_put(cooling_spec.np); + + if (cooling_spec.args_count < 2) { + pr_err("wrong reference to cooling device, missing limits\n"); + return -EINVAL; + } + + if (cooling_spec.np != cdev->np) + return 0; + + ret = thermal_zone_bind_cooling_device(tz, trip_id, cdev, cooling_spec.args[1], + cooling_spec.args[0], + weight); + if (ret) + pr_err("Failed to bind '%s' with '%s': %d\n", tz->type, cdev->type, ret); + + return ret; +} + +static int thermal_of_for_each_cooling_device(struct device_node *tz_np, struct device_node *map_np, + struct thermal_zone_device *tz, struct thermal_cooling_device *cdev, + int (*action)(struct device_node *, int, int, + struct thermal_zone_device *, struct thermal_cooling_device *)) +{ + struct device_node *tr_np; + int count, i, trip_id; + + tr_np = of_parse_phandle(map_np, "trip", 0); + if (!tr_np) + return -ENODEV; + + trip_id = of_find_trip_id(tz_np, tr_np); + if (trip_id < 0) + return trip_id; + + count = of_count_phandle_with_args(map_np, "cooling-device", "#cooling-cells"); + if (count <= 0) { + pr_err("Add a cooling_device property with at least one device\n"); + return -ENOENT; + } + + /* + * At this point, we don't want to bail out when there is an + * error, we will try to bind/unbind as many as possible + * cooling devices + */ + for (i = 0; i < count; i++) + action(map_np, i, trip_id, tz, cdev); + + return 0; +} + +static int thermal_of_for_each_cooling_maps(struct thermal_zone_device *tz, + struct thermal_cooling_device *cdev, + int (*action)(struct device_node *, int, int, + struct thermal_zone_device *, struct thermal_cooling_device *)) +{ + struct device_node *tz_np, *cm_np, *child; + int ret = 0; + + 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 PTR_ERR(tz_np); + } + + cm_np = of_get_child_by_name(tz_np, "cooling-maps"); + if (!cm_np) + goto out; + + for_each_child_of_node(cm_np, child) { + ret = thermal_of_for_each_cooling_device(tz_np, child, tz, cdev, action); + if (ret) { + of_node_put(child); + break; + } + } + + of_node_put(cm_np); +out: + of_node_put(tz_np); + + return ret; +} + +static int thermal_of_bind(struct thermal_zone_device *tz, + struct thermal_cooling_device *cdev) +{ + return thermal_of_for_each_cooling_maps(tz, cdev, __thermal_of_bind); +} + +static int thermal_of_unbind(struct thermal_zone_device *tz, + struct thermal_cooling_device *cdev) +{ + return thermal_of_for_each_cooling_maps(tz, cdev, __thermal_of_unbind); +} + +/** + * 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 + */ +void thermal_of_zone_unregister(struct thermal_zone_device *tz) +{ + struct thermal_trip *trips = tz->trips; + struct thermal_zone_params *tzp = tz->tzp; + struct thermal_zone_device_ops *ops = tz->ops; + + thermal_zone_device_disable(tz); + thermal_zone_device_unregister(tz); + kfree(trips); + kfree(tzp); + kfree(ops); +} +EXPORT_SYMBOL_GPL(thermal_of_zone_unregister); + +/** + * 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 + */ +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 *tz; + struct thermal_trip *trips; + struct thermal_zone_params *tzp; + struct thermal_zone_device_ops *of_ops; + struct device_node *np; + int delay, pdelay; + int ntrips, mask; + int ret; + + of_ops = kmemdup(ops, sizeof(*ops), GFP_KERNEL); + if (!of_ops) + return ERR_PTR(-ENOMEM); + + 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); + ret = PTR_ERR(np); + goto out_kfree_of_ops; + } + + trips = thermal_of_trips_init(np, &ntrips); + if (IS_ERR(trips)) { + pr_err("Failed to find trip points for %pOFn id=%d\n", sensor, id); + ret = PTR_ERR(trips); + goto out_kfree_of_ops; + } + + 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; + } + + tzp = thermal_of_parameters_init(np); + if (IS_ERR(tzp)) { + ret = PTR_ERR(tzp); + pr_err("Failed to initialize parameter from %pOFn: %d\n", np, ret); + goto out_kfree_trips; + } + + of_ops->get_trip_type = of_ops->get_trip_type ? : of_thermal_get_trip_type; + of_ops->get_trip_temp = of_ops->get_trip_temp ? : of_thermal_get_trip_temp; + of_ops->get_trip_hyst = of_ops->get_trip_hyst ? : of_thermal_get_trip_hyst; + of_ops->set_trip_hyst = of_ops->set_trip_hyst ? : of_thermal_set_trip_hyst; + of_ops->get_crit_temp = of_ops->get_crit_temp ? : of_thermal_get_crit_temp; + of_ops->bind = thermal_of_bind; + of_ops->unbind = thermal_of_unbind; + + mask = GENMASK_ULL((ntrips) - 1, 0); + + tz = thermal_zone_device_register_with_trips(np->name, trips, ntrips, + mask, 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_tzp; + } + + 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_tzp: + kfree(tzp); +out_kfree_trips: + kfree(trips); +out_kfree_of_ops: + kfree(of_ops); + + return ERR_PTR(ret); +} +EXPORT_SYMBOL_GPL(thermal_of_zone_register); + +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); |