diff options
Diffstat (limited to 'drivers/thermal/thermal_of.c')
| -rw-r--r-- | drivers/thermal/thermal_of.c | 652 |
1 files changed, 652 insertions, 0 deletions
diff --git a/drivers/thermal/thermal_of.c b/drivers/thermal/thermal_of.c new file mode 100644 index 000000000..0217a49b0 --- /dev/null +++ b/drivers/thermal/thermal_of.c @@ -0,0 +1,652 @@ +// 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) +{ + int ret, count; + + *ntrips = 0; + + struct device_node *trips __free(device_node) = of_get_child_by_name(np, "trips"); + if (!trips) + return NULL; + + count = of_get_child_count(trips); + if (!count) + return NULL; + + struct thermal_trip *tt __free(kfree) = kzalloc_objs(*tt, count); + if (!tt) + return ERR_PTR(-ENOMEM); + + count = 0; + for_each_child_of_node_scoped(trips, trip) { + ret = thermal_of_populate_trip(trip, &tt[count++]); + if (ret) + return ERR_PTR(ret); + } + + *ntrips = count; + + return no_free_ptr(tt); +} + +static struct device_node *of_thermal_zone_find(struct device_node *sensor, int id) +{ + struct of_phandle_args sensor_specs; + + struct device_node *np __free(device_node) = 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("%pOFP: missing thermal sensor\n", child); + return ERR_PTR(-EINVAL); + } + + 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("%pOFP: Failed to read thermal-sensors cells: %d\n", child, ret); + return ERR_PTR(ret); + } + + of_node_put(sensor_specs.np); + if ((sensor == sensor_specs.np) && id == (sensor_specs.args_count ? + sensor_specs.args[0] : 0)) { + pr_debug("sensor %pOFP id=%d belongs to %pOFP\n", sensor, id, child); + return no_free_ptr(child); + } + } + } + + return ERR_PTR(-ENODEV); +} + +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("%pOFP: 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("%pOFP: 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); + + /* + * There are two formats: + * - Legacy format : <&cdev lower upper> + * - New format : <&cdev cdev_id lower upper> + * + * With the new format, along with the device node pointer, + * the cdev_id must match with the cooling device cdev_id in + * order to bind + */ + if (cooling_spec.args_count < 2 || cooling_spec.args_count > 3) { + pr_err("Invalid number of cooling device parameters\n"); + return false; + } + + if (cooling_spec.np != cdev->np) + return false; + + if (cooling_spec.args_count == 3 && + cooling_spec.args[0] != cdev->cdev_id) + return false; + + if (cooling_spec.args_count != 3) { + c->lower = cooling_spec.args[0]; + c->upper = cooling_spec.args[1]; + } else { + c->lower = cooling_spec.args[1]; + c->upper = cooling_spec.args[2]; + } + c->weight = weight; + + return true; +} + +static bool thermal_of_cm_lookup(struct device_node *cm_np, + const struct thermal_trip *trip, + struct thermal_cooling_device *cdev, + struct cooling_spec *c) +{ + for_each_child_of_node_scoped(cm_np, child) { + int count, i; + + struct device_node *tr_np __free(device_node) = + 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++) { + if (thermal_of_get_cooling_spec(child, i, cdev, c)) + return true; + } + } + + return false; +} + +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; + 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. */ + result = thermal_of_cm_lookup(cm_np, trip, cdev, c); + + 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 %pOFP 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 %pOFP id=%d\n", sensor, id); + ret = PTR_ERR(trips); + goto out_of_node_put; + } + + if (!trips) + pr_info("No trip points found for %pOFP id=%d\n", sensor, id); + + ret = thermal_of_monitor_init(np, &delay, &pdelay); + if (ret) { + pr_err("Failed to initialize monitoring delays from %pOFP\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 && !of_ops.critical) { + if (!strcasecmp(action, "reboot")) + of_ops.critical = thermal_zone_device_critical_reboot; + else if (!strcasecmp(action, "shutdown")) + of_ops.critical = thermal_zone_device_critical_shutdown; + } + + 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 %pOFP: %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 enable 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 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); + +/** + * thermal_of_cooling_device_register() - register an OF thermal cooling device + * @np: a pointer to a device tree node. + * @cdev_id: a cooling device id in the cooling controller + * @type: the thermal cooling device type. + * @devdata: device private data. + * @ops: standard thermal cooling devices callbacks. + * + * This interface function adds a new thermal cooling device (fan/processor/...) + * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself + * to all the thermal zone devices registered at the same time. + * It also gives the opportunity to link the cooling device to a device tree + * node, so that it can be bound to a thermal zone created out of device tree. + * + * Return: a pointer to the created struct thermal_cooling_device or an + * ERR_PTR. Caller must check return value with IS_ERR*() helpers. + */ +struct thermal_cooling_device * +thermal_of_cooling_device_register(struct device_node *np, u32 cdev_id, + const char *type, void *devdata, + const struct thermal_cooling_device_ops *ops) +{ + struct thermal_cooling_device *cdev; + int ret; + + cdev = thermal_cooling_device_alloc(type, ops); + if (IS_ERR(cdev)) + return cdev; + + cdev->np = np; + cdev->cdev_id = cdev_id; + + ret = thermal_cooling_device_add(cdev, devdata); + if (ret) + return ERR_PTR(ret); + + return cdev; +} +EXPORT_SYMBOL_GPL(thermal_of_cooling_device_register); + +static void thermal_of_cooling_device_release(void *data) +{ + struct thermal_cooling_device *cdev = data; + + thermal_cooling_device_unregister(cdev); +} + +static struct thermal_cooling_device * +__devm_thermal_of_cooling_device_register(struct device *dev, struct device_node *np, + u32 cdev_id, const char *type, void *devdata, + const struct thermal_cooling_device_ops *ops) +{ + struct thermal_cooling_device *cdev; + int ret; + + cdev = thermal_of_cooling_device_register(np, cdev_id, type, devdata, ops); + if (IS_ERR(cdev)) + return cdev; + + ret = devm_add_action_or_reset(dev, thermal_of_cooling_device_release, cdev); + if (ret) + return ERR_PTR(ret); + + return cdev; +} + +/** + * devm_thermal_of_cooling_device_register() - register an OF thermal cooling device + * @dev: a valid struct device pointer of a sensor device. + * @cdev_id: a cooling device index in the cooling controller + * @type: the thermal cooling device type. + * @devdata: device private data. + * @ops: standard thermal cooling devices callbacks. + * + * This function will register a cooling device with device tree node reference. + * This interface function adds a new thermal cooling device (fan/processor/...) + * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself + * to all the thermal zone devices registered at the same time. + * + * Return: a pointer to the created struct thermal_cooling_device or an + * ERR_PTR. Caller must check return value with IS_ERR*() helpers. + */ +struct thermal_cooling_device * +devm_thermal_of_cooling_device_register(struct device *dev, u32 cdev_id, + const char *type, void *devdata, + const struct thermal_cooling_device_ops *ops) +{ + return __devm_thermal_of_cooling_device_register(dev, dev->of_node, cdev_id, + type, devdata, ops); +} +EXPORT_SYMBOL_GPL(devm_thermal_of_cooling_device_register); + +/** + * devm_thermal_of_child_cooling_device_register() - register an OF thermal cooling + * device + * @dev: a valid struct device pointer of a sensor device. + * @np: a pointer to a device tree node. + * @type: the thermal cooling device type. + * @devdata: device private data. + * @ops: standard thermal cooling devices callbacks. + * + * This function will register a cooling device with device tree node reference. + * This interface function adds a new thermal cooling device (fan/processor/...) + * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself + * to all the thermal zone devices registered at the same time. + * + * This function should be used when a cooling controller has child + * nodes which are referenced in the thermal zone cooling map. + * + * Return: a pointer to the created struct thermal_cooling_device or an + * ERR_PTR. Caller must check return value with IS_ERR*() helpers. + */ +struct thermal_cooling_device * +devm_thermal_of_child_cooling_device_register(struct device *dev, + struct device_node *np, + const char *type, void *devdata, + const struct thermal_cooling_device_ops *ops) +{ + return __devm_thermal_of_cooling_device_register(dev, np, 0, type, devdata, ops); +} +EXPORT_SYMBOL_GPL(devm_thermal_of_child_cooling_device_register); |