| Message ID | 20210906190454.114751-3-abailon@baylibre.com (mailing list archive) |
|---|---|
| State | Changes Requested, archived |
| Delegated to: | Zhang Rui |
| Headers | show |
| Series | Add a generic virtual thermal sensor | expand |
On Mon, Sep 06, 2021 at 09:04:54PM +0200, Alexandre Bailon wrote: > This adds a virtual thermal sensor that reads temperature from > hardware sensor and return an aggregated temperature. s/hardware sensor/hardware sensors/ > Currently, this only return the max temperature. it seems this is outdated. > Signed-off-by: Alexandre Bailon <abailon@baylibre.com> > --- > drivers/thermal/Kconfig | 8 + > drivers/thermal/Makefile | 1 + > drivers/thermal/virtual-sensor.h | 51 ++++ > drivers/thermal/virtual_sensor.c | 400 +++++++++++++++++++++++++++++++ > 4 files changed, 460 insertions(+) > create mode 100644 drivers/thermal/virtual-sensor.h > create mode 100644 drivers/thermal/virtual_sensor.c > > diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig > index 7a4ba50ba97d0..23dc903da2fc5 100644 > --- a/drivers/thermal/Kconfig > +++ b/drivers/thermal/Kconfig > @@ -228,6 +228,14 @@ config THERMAL_MMIO > register or shared memory, is a potential candidate to work with this > driver. > > +config VIRTUAL_THERMAL > + tristate "Generic virtual thermal sensor driver" Not sure if 'Generic' adds much value here. > + depends on THERMAL_OF || COMPILE_TEST > + help > + This option enables the generic thermal sensor aggregator. > + This driver creates a thermal sensor that reads the hardware sensors > + and aggregate the temperature. > + > config HISI_THERMAL > tristate "Hisilicon thermal driver" > depends on ARCH_HISI || COMPILE_TEST > diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile > index 9729a2b089919..76dfa1d61bfc5 100644 > --- a/drivers/thermal/Makefile > +++ b/drivers/thermal/Makefile > @@ -60,3 +60,4 @@ obj-$(CONFIG_UNIPHIER_THERMAL) += uniphier_thermal.o > obj-$(CONFIG_AMLOGIC_THERMAL) += amlogic_thermal.o > obj-$(CONFIG_SPRD_THERMAL) += sprd_thermal.o > obj-$(CONFIG_KHADAS_MCU_FAN_THERMAL) += khadas_mcu_fan.o > +obj-$(CONFIG_VIRTUAL_THERMAL) += virtual_sensor.o > diff --git a/drivers/thermal/virtual-sensor.h b/drivers/thermal/virtual-sensor.h > new file mode 100644 > index 0000000000000..e024d434856c7 > --- /dev/null > +++ b/drivers/thermal/virtual-sensor.h > @@ -0,0 +1,51 @@ > +/* SPDX-License-Identifier: GPL-2.0 */ > +/* > + * Copyright (c) 2021 BayLibre > + */ > + > +#ifndef __THERMAL_VIRTUAL_SENSOR_H__ > +#define __THERMAL_VIRTUAL_SENSOR_H__ > + > +struct virtual_sensor; > +struct virtual_sensor_data; Other types of virtual sensors could be added in the future, you might want to name these virtual_thermal_sensor(_data). Then again, these structs are of internal use only, so it's probably not super important. > + > +#ifdef CONFIG_VIRTUAL_THERMAL > +struct virtual_sensor_data * > +thermal_virtual_sensor_register(struct device *dev, int sensor_id, void *data, > + const struct thermal_zone_of_device_ops *ops); > +void thermal_virtual_sensor_unregister(struct device *dev, > + struct virtual_sensor_data *sensor_data); > +struct virtual_sensor_data * > +devm_thermal_virtual_sensor_register(struct device *dev, int sensor_id, void *data, > + const struct thermal_zone_of_device_ops *ops); > + > +void devm_thermal_virtual_sensor_unregister(struct device *dev, > + struct virtual_sensor *sensor); > +#else > +static inline struct virtual_sensor_data * > +thermal_virtual_sensor_register(struct device *dev, int sensor_id, void *data, > + const struct thermal_zone_of_device_ops *ops) > +{ > + return ERR_PTR(-ENODEV); > +} > + > +void thermal_virtual_sensor_unregister(struct device *dev, > + struct virtual_sensor_data *sensor_data) > +{ > +} > + > +static inline struct virtual_sensor_data * > +devm_thermal_virtual_sensor_register(struct device *dev, int sensor_id, void *data, > + const struct thermal_zone_of_device_ops *ops) > +{ > + return ERR_PTR(-ENODEV); > +} > + > +static inline > +void devm_thermal_virtual_sensor_unregister(struct device *dev, > + struct virtual_sensor *sensor) > +{ > +} > +#endif > + > +#endif /* __THERMAL_VIRTUAL_SENSOR_H__ */ > diff --git a/drivers/thermal/virtual_sensor.c b/drivers/thermal/virtual_sensor.c > new file mode 100644 > index 0000000000000..e5bb0ef9adb39 > --- /dev/null > +++ b/drivers/thermal/virtual_sensor.c > @@ -0,0 +1,400 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * Copyright (c) 2021 BayLibre > + */ > + > +#include <linux/err.h> > +#include <linux/export.h> > +#include <linux/module.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 <dt-bindings/thermal/virtual-sensor.h> > + > +#include "virtual-sensor.h" > + > +struct virtual_sensor_data { This struct (typically) corresponds to an actual sensor, maybe name it 'thermal_sensor_data' instead? > + struct list_head node; > + > + /* sensor interface */ > + int id; > + void *sensor_data; > + const struct thermal_zone_of_device_ops *ops; > +}; > + > +struct virtual_sensor { > + int count; > + struct virtual_sensor_data *sensors; > + struct thermal_zone_device *tzd; > + > + struct list_head node; > +}; > + > +static LIST_HEAD(thermal_sensors); > +static LIST_HEAD(virtual_sensors); > + > +static int virtual_sensor_get_temp_max(void *data, int *temperature) > +{ > + struct virtual_sensor *sensor = data; > + int max_temp = INT_MIN; > + int temp; > + int i; > + > + for (i = 0; i < sensor->count; i++) { > + struct virtual_sensor_data *hw_sensor; > + > + hw_sensor = &sensor->sensors[i]; > + if (!hw_sensor->ops) > + return -ENODEV; > + > + hw_sensor->ops->get_temp(hw_sensor->sensor_data, &temp); > + max_temp = max(max_temp, temp); > + } > + > + *temperature = max_temp; > + > + return 0; > +} > + > +static const struct thermal_zone_of_device_ops virtual_sensor_max_ops = { > + .get_temp = virtual_sensor_get_temp_max, > +}; > + > +static int virtual_sensor_get_temp_min(void *data, int *temperature) > +{ > + struct virtual_sensor *sensor = data; > + int min_temp = INT_MAX; > + int temp; > + int i; > + > + for (i = 0; i < sensor->count; i++) { > + struct virtual_sensor_data *hw_sensor; > + > + hw_sensor = &sensor->sensors[i]; > + if (!hw_sensor->ops) > + return -ENODEV; > + > + hw_sensor->ops->get_temp(hw_sensor->sensor_data, &temp); > + min_temp = min(min_temp, temp); > + } > + > + *temperature = min_temp; > + > + return 0; > +} > + > +static const struct thermal_zone_of_device_ops virtual_sensor_min_ops = { > + .get_temp = virtual_sensor_get_temp_min, > +}; > + > +static int do_avg(int val1, int val2) > +{ > + return ((val1) / 2) + ((val2) / 2) + (((val1) % 2 + (val2) % 2) / 2); > +} > + > +static int virtual_sensor_get_temp_avg(void *data, int *temperature) > +{ > + struct virtual_sensor *sensor = data; > + int avg_temp = 0; > + int temp; > + int i; > + > + for (i = 0; i < sensor->count; i++) { > + struct virtual_sensor_data *hw_sensor; > + > + hw_sensor = &sensor->sensors[i]; > + if (!hw_sensor->ops) > + return -ENODEV; > + > + hw_sensor->ops->get_temp(hw_sensor->sensor_data, &temp); > + avg_temp = do_avg(avg_temp, temp); > + } > + > + *temperature = avg_temp; > + > + return 0; > +} _get_temp_min(), _get_temp_max() and _get_temp_avg() have the same structure, the only differences is the aggregator function and the initialization value. If you wanted to save a few lines of code you could have a meta-function that receives the initialization value and a pointer of the aggregator function. The functions are relatively short though, so I wouldn't claim that it would be a huge improvement, one could also argue that the code is easier to follow as is. > + > +static const struct thermal_zone_of_device_ops virtual_sensor_avg_ops = { > + .get_temp = virtual_sensor_get_temp_avg, > +}; > + > +static int register_virtual_sensor(struct virtual_sensor *sensor, > + struct of_phandle_args args, > + int index) Does this really register a virtual sensor? IIUC the registered sensor is (typically) an actual sensor, which is used by a virtual sensor. Shouldn't it be something like 'register_thermal_sensor' or 'virtual_sensor_add_sensor'? > +{ > + struct virtual_sensor_data *sensor_data; > + int id; > + > + list_for_each_entry(sensor_data, &thermal_sensors, node) { > + id = args.args_count ? args.args[0] : 0; > + if (sensor_data->id == id) { > + memcpy(&sensor->sensors[index], sensor_data, > + sizeof(*sensor_data)); > + return 0; > + } > + } > + > + return -ENODEV; > +} > + > +static int virtual_sensor_probe(struct platform_device *pdev) > +{ > + const struct thermal_zone_of_device_ops *ops; > + struct virtual_sensor *sensor; > + struct device *dev = &pdev->dev; > + struct of_phandle_args args; > + u32 type; > + int ret; > + int i; > + > + sensor = devm_kzalloc(dev, sizeof(*sensor), GFP_KERNEL); > + if (!sensor) > + return -ENOMEM; > + > + sensor->count = of_count_phandle_with_args(dev->of_node, > + "thermal-sensors", > + "#thermal-sensor-cells"); > + if (sensor->count <= 0) > + return -EINVAL; > + > + sensor->sensors = devm_kmalloc_array(dev, sensor->count, > + sizeof(*sensor->sensors), > + GFP_KERNEL); > + if (!sensor->sensors) > + return -ENOMEM; > + > + for (i = 0; i < sensor->count; i++) { > + ret = of_parse_phandle_with_args(dev->of_node, > + "thermal-sensors", > + "#thermal-sensor-cells", > + i, > + &args); > + if (ret) > + return ret; > + > + ret = register_virtual_sensor(sensor, args, i); > + if (ret) > + return ret; > + } > + > + ret = of_property_read_u32(dev->of_node, "type", &type); More a question for the binding, butthis should probably be something more specific than 'type', like 'aggregation-function'. > + if (ret) > + return ret; > + > + switch (type) { > + case VIRTUAL_SENSOR_MAX: > + ops = &virtual_sensor_max_ops; > + break; > + case VIRTUAL_SENSOR_MIN: > + ops = &virtual_sensor_min_ops; > + break; > + case VIRTUAL_SENSOR_AVG: > + ops = &virtual_sensor_avg_ops; > + break; > + default: > + return -EINVAL; > + } > + > + sensor->tzd = devm_thermal_zone_of_sensor_register(dev, 0, sensor, ops); > + if (IS_ERR(sensor->tzd)) > + return PTR_ERR(sensor->tzd); > + > + platform_set_drvdata(pdev, sensor); > + list_add(&sensor->node, &virtual_sensors); If you also added the sensor to 'thermal_sensors' you could support virtual sensors using virtual sensors, though it's not clear how useful that would be in practice and it could raise issues with the initialization order. > + > + return 0; > +} > + > +static int virtual_sensor_remove(struct platform_device *pdev) > +{ > + struct device *dev = &pdev->dev; > + struct virtual_sensor *sensor; > + > + sensor = platform_get_drvdata(pdev); > + list_del(&sensor->node); > + > + devm_thermal_zone_of_sensor_unregister(dev, sensor->tzd); > + devm_kfree(dev, sensor->sensors); > + devm_kfree(dev, sensor); Are the above 3 statements really needed, shouldn't devm_* handle that automagically? > + > + return 0; > +} > + > +static const struct of_device_id virtual_sensor_of_match[] = { > + { > + .compatible = "virtual,thermal-sensor", > + }, > + { > + }, > +}; > +MODULE_DEVICE_TABLE(of, thermal_aggr_of_match); > + > +static struct platform_driver virtual_sensor = { > + .probe = virtual_sensor_probe, > + .remove = virtual_sensor_remove, > + .driver = { > + .name = "virtual-sensor", I suggest to change it to 'virtual-thermal-sensor' since there might be other types of virtual sensors. > + .of_match_table = virtual_sensor_of_match, > + }, > +}; > + > +/** > + * thermal_virtual_sensor_register - registers a sensor that could by a virtual s/by/be/ > + * sensor > + * @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 s/sensors/sensor/ > + * @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 register a thermal sensor to make it available for later > + * usage by a virtual sensor. > + * > + * The thermal zone temperature is provided by the @get_temp function > + * pointer. When called, it will have the private pointer @data back. > + * > + * 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 virtual_sensor_data *thermal_virtual_sensor_register( > + struct device *dev, int sensor_id, void *data, > + const struct thermal_zone_of_device_ops *ops) > +{ > + struct virtual_sensor_data *sensor_data; > + > + sensor_data = devm_kzalloc(dev, sizeof(*sensor_data), GFP_KERNEL); > + if (!sensor_data) > + return ERR_PTR(-ENOMEM); > + > + sensor_data->id = sensor_id; > + sensor_data->sensor_data = data; > + sensor_data->ops = ops; > + > + list_add(&sensor_data->node, &thermal_sensors); > + > + return sensor_data; > +} > +EXPORT_SYMBOL_GPL(thermal_virtual_sensor_register); > + > +/** > + * thermal_virtual_sensor_unregister - unregisters a sensor > + * @dev: a valid struct device pointer of a sensor device. > + * @sensor_data: a pointer to struct virtual_sensor_data to unregister. > + * > + * This function removes the sensor from the list of available thermal sensors. > + * If the sensor is in use, then the next call to .get_temp will return -ENODEV. > + */ > +void thermal_virtual_sensor_unregister(struct device *dev, > + struct virtual_sensor_data *sensor_data) > +{ > + struct virtual_sensor_data *temp; 'temp' might not be the best name in this context, since it's associated with temperature. Maybe name it 'sd'? > + struct virtual_sensor *sensor; > + int i; > + > + list_del(&sensor_data->node); > + > + list_for_each_entry(sensor, &virtual_sensors, node) { > + for (i = 0; i < sensor->count; i++) { > + temp = &sensor->sensors[i]; > + if (temp->id == sensor_data->id && > + temp->sensor_data == sensor_data->sensor_data) { > + temp->ops = NULL; > + } > + } > + } > + devm_kfree(dev, sensor_data); Does it actually make sense to allocate the memory with devm_kzalloc() if it is explicitly freed here? > +} > +EXPORT_SYMBOL_GPL(thermal_virtual_sensor_unregister); > + > +static void devm_thermal_virtual_sensor_release(struct device *dev, void *res) > +{ > + thermal_virtual_sensor_unregister(dev, > + *(struct virtual_sensor_data **)res); > +} > + > +static int devm_thermal_virtual_sensor_match(struct device *dev, void *res, > + void *data) > +{ > + struct virtual_sensor_data **r = res; > + > + if (WARN_ON(!r || !*r)) > + return 0; > + > + return *r == data; > +} > + > + delete one of the empty lines > +/** > + * devm_thermal_virtual_sensor_register - Resource managed version of > + * thermal_virtual_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 s/sensors/sensor/ > + * @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 virtual_sensor_data, > + * otherwise, it returns a corresponding ERR_PTR(). Caller must > + * check the return value with help of IS_ERR() helper. > + * Registered virtual_sensor_data device will automatically be > + * released when device is unbounded. s/unbounded/unbound/
Hi Matthias, On 9/10/21 12:29 AM, Matthias Kaehlcke wrote: > On Mon, Sep 06, 2021 at 09:04:54PM +0200, Alexandre Bailon wrote: >> This adds a virtual thermal sensor that reads temperature from >> hardware sensor and return an aggregated temperature. > s/hardware sensor/hardware sensors/ > >> Currently, this only return the max temperature. > it seems this is outdated. > >> Signed-off-by: Alexandre Bailon <abailon@baylibre.com> >> --- >> drivers/thermal/Kconfig | 8 + >> drivers/thermal/Makefile | 1 + >> drivers/thermal/virtual-sensor.h | 51 ++++ >> drivers/thermal/virtual_sensor.c | 400 +++++++++++++++++++++++++++++++ >> 4 files changed, 460 insertions(+) >> create mode 100644 drivers/thermal/virtual-sensor.h >> create mode 100644 drivers/thermal/virtual_sensor.c >> >> diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig >> index 7a4ba50ba97d0..23dc903da2fc5 100644 >> --- a/drivers/thermal/Kconfig >> +++ b/drivers/thermal/Kconfig >> @@ -228,6 +228,14 @@ config THERMAL_MMIO >> register or shared memory, is a potential candidate to work with this >> driver. >> >> +config VIRTUAL_THERMAL >> + tristate "Generic virtual thermal sensor driver" > Not sure if 'Generic' adds much value here. > >> + depends on THERMAL_OF || COMPILE_TEST >> + help >> + This option enables the generic thermal sensor aggregator. >> + This driver creates a thermal sensor that reads the hardware sensors >> + and aggregate the temperature. >> + >> config HISI_THERMAL >> tristate "Hisilicon thermal driver" >> depends on ARCH_HISI || COMPILE_TEST >> diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile >> index 9729a2b089919..76dfa1d61bfc5 100644 >> --- a/drivers/thermal/Makefile >> +++ b/drivers/thermal/Makefile >> @@ -60,3 +60,4 @@ obj-$(CONFIG_UNIPHIER_THERMAL) += uniphier_thermal.o >> obj-$(CONFIG_AMLOGIC_THERMAL) += amlogic_thermal.o >> obj-$(CONFIG_SPRD_THERMAL) += sprd_thermal.o >> obj-$(CONFIG_KHADAS_MCU_FAN_THERMAL) += khadas_mcu_fan.o >> +obj-$(CONFIG_VIRTUAL_THERMAL) += virtual_sensor.o >> diff --git a/drivers/thermal/virtual-sensor.h b/drivers/thermal/virtual-sensor.h >> new file mode 100644 >> index 0000000000000..e024d434856c7 >> --- /dev/null >> +++ b/drivers/thermal/virtual-sensor.h >> @@ -0,0 +1,51 @@ >> +/* SPDX-License-Identifier: GPL-2.0 */ >> +/* >> + * Copyright (c) 2021 BayLibre >> + */ >> + >> +#ifndef __THERMAL_VIRTUAL_SENSOR_H__ >> +#define __THERMAL_VIRTUAL_SENSOR_H__ >> + >> +struct virtual_sensor; >> +struct virtual_sensor_data; > Other types of virtual sensors could be added in the future, you might > want to name these virtual_thermal_sensor(_data). Then again, these > structs are of internal use only, so it's probably not super important. You are right. This might become confusing at some point. I will rename them. > >> + >> +#ifdef CONFIG_VIRTUAL_THERMAL >> +struct virtual_sensor_data * >> +thermal_virtual_sensor_register(struct device *dev, int sensor_id, void *data, >> + const struct thermal_zone_of_device_ops *ops); >> +void thermal_virtual_sensor_unregister(struct device *dev, >> + struct virtual_sensor_data *sensor_data); >> +struct virtual_sensor_data * >> +devm_thermal_virtual_sensor_register(struct device *dev, int sensor_id, void *data, >> + const struct thermal_zone_of_device_ops *ops); >> + >> +void devm_thermal_virtual_sensor_unregister(struct device *dev, >> + struct virtual_sensor *sensor); >> +#else >> +static inline struct virtual_sensor_data * >> +thermal_virtual_sensor_register(struct device *dev, int sensor_id, void *data, >> + const struct thermal_zone_of_device_ops *ops) >> +{ >> + return ERR_PTR(-ENODEV); >> +} >> + >> +void thermal_virtual_sensor_unregister(struct device *dev, >> + struct virtual_sensor_data *sensor_data) >> +{ >> +} >> + >> +static inline struct virtual_sensor_data * >> +devm_thermal_virtual_sensor_register(struct device *dev, int sensor_id, void *data, >> + const struct thermal_zone_of_device_ops *ops) >> +{ >> + return ERR_PTR(-ENODEV); >> +} >> + >> +static inline >> +void devm_thermal_virtual_sensor_unregister(struct device *dev, >> + struct virtual_sensor *sensor) >> +{ >> +} >> +#endif >> + >> +#endif /* __THERMAL_VIRTUAL_SENSOR_H__ */ >> diff --git a/drivers/thermal/virtual_sensor.c b/drivers/thermal/virtual_sensor.c >> new file mode 100644 >> index 0000000000000..e5bb0ef9adb39 >> --- /dev/null >> +++ b/drivers/thermal/virtual_sensor.c >> @@ -0,0 +1,400 @@ >> +// SPDX-License-Identifier: GPL-2.0 >> +/* >> + * Copyright (c) 2021 BayLibre >> + */ >> + >> +#include <linux/err.h> >> +#include <linux/export.h> >> +#include <linux/module.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 <dt-bindings/thermal/virtual-sensor.h> >> + >> +#include "virtual-sensor.h" >> + >> +struct virtual_sensor_data { > This struct (typically) corresponds to an actual sensor, maybe name it > 'thermal_sensor_data' instead? > >> + struct list_head node; >> + >> + /* sensor interface */ >> + int id; >> + void *sensor_data; >> + const struct thermal_zone_of_device_ops *ops; >> +}; >> + >> +struct virtual_sensor { >> + int count; >> + struct virtual_sensor_data *sensors; >> + struct thermal_zone_device *tzd; >> + >> + struct list_head node; >> +}; >> + >> +static LIST_HEAD(thermal_sensors); >> +static LIST_HEAD(virtual_sensors); >> + >> +static int virtual_sensor_get_temp_max(void *data, int *temperature) >> +{ >> + struct virtual_sensor *sensor = data; >> + int max_temp = INT_MIN; >> + int temp; >> + int i; >> + >> + for (i = 0; i < sensor->count; i++) { >> + struct virtual_sensor_data *hw_sensor; >> + >> + hw_sensor = &sensor->sensors[i]; >> + if (!hw_sensor->ops) >> + return -ENODEV; >> + >> + hw_sensor->ops->get_temp(hw_sensor->sensor_data, &temp); >> + max_temp = max(max_temp, temp); >> + } >> + >> + *temperature = max_temp; >> + >> + return 0; >> +} >> + >> +static const struct thermal_zone_of_device_ops virtual_sensor_max_ops = { >> + .get_temp = virtual_sensor_get_temp_max, >> +}; >> + >> +static int virtual_sensor_get_temp_min(void *data, int *temperature) >> +{ >> + struct virtual_sensor *sensor = data; >> + int min_temp = INT_MAX; >> + int temp; >> + int i; >> + >> + for (i = 0; i < sensor->count; i++) { >> + struct virtual_sensor_data *hw_sensor; >> + >> + hw_sensor = &sensor->sensors[i]; >> + if (!hw_sensor->ops) >> + return -ENODEV; >> + >> + hw_sensor->ops->get_temp(hw_sensor->sensor_data, &temp); >> + min_temp = min(min_temp, temp); >> + } >> + >> + *temperature = min_temp; >> + >> + return 0; >> +} >> + >> +static const struct thermal_zone_of_device_ops virtual_sensor_min_ops = { >> + .get_temp = virtual_sensor_get_temp_min, >> +}; >> + >> +static int do_avg(int val1, int val2) >> +{ >> + return ((val1) / 2) + ((val2) / 2) + (((val1) % 2 + (val2) % 2) / 2); >> +} >> + >> +static int virtual_sensor_get_temp_avg(void *data, int *temperature) >> +{ >> + struct virtual_sensor *sensor = data; >> + int avg_temp = 0; >> + int temp; >> + int i; >> + >> + for (i = 0; i < sensor->count; i++) { >> + struct virtual_sensor_data *hw_sensor; >> + >> + hw_sensor = &sensor->sensors[i]; >> + if (!hw_sensor->ops) >> + return -ENODEV; >> + >> + hw_sensor->ops->get_temp(hw_sensor->sensor_data, &temp); >> + avg_temp = do_avg(avg_temp, temp); >> + } >> + >> + *temperature = avg_temp; >> + >> + return 0; >> +} > _get_temp_min(), _get_temp_max() and _get_temp_avg() have the same > structure, the only differences is the aggregator function and the > initialization value. If you wanted to save a few lines of code you > could have a meta-function that receives the initialization value and > a pointer of the aggregator function. > > The functions are relatively short though, so I wouldn't claim that > it would be a huge improvement, one could also argue that the code is > easier to follow as is. My intent was to make possible adding more complex functions. I will factorize the code, and if later there are some use cases, we will made the update to support more complex functions. > >> + >> +static const struct thermal_zone_of_device_ops virtual_sensor_avg_ops = { >> + .get_temp = virtual_sensor_get_temp_avg, >> +}; >> + >> +static int register_virtual_sensor(struct virtual_sensor *sensor, >> + struct of_phandle_args args, >> + int index) > Does this really register a virtual sensor? IIUC the registered sensor is > (typically) an actual sensor, which is used by a virtual sensor. > > Shouldn't it be something like 'register_thermal_sensor' or > 'virtual_sensor_add_sensor'? You are right, virtual_sensor_add_sensor sounds a lot better. > >> +{ >> + struct virtual_sensor_data *sensor_data; >> + int id; >> + >> + list_for_each_entry(sensor_data, &thermal_sensors, node) { >> + id = args.args_count ? args.args[0] : 0; >> + if (sensor_data->id == id) { >> + memcpy(&sensor->sensors[index], sensor_data, >> + sizeof(*sensor_data)); >> + return 0; >> + } >> + } >> + >> + return -ENODEV; >> +} >> + >> +static int virtual_sensor_probe(struct platform_device *pdev) >> +{ >> + const struct thermal_zone_of_device_ops *ops; >> + struct virtual_sensor *sensor; >> + struct device *dev = &pdev->dev; >> + struct of_phandle_args args; >> + u32 type; >> + int ret; >> + int i; >> + >> + sensor = devm_kzalloc(dev, sizeof(*sensor), GFP_KERNEL); >> + if (!sensor) >> + return -ENOMEM; >> + >> + sensor->count = of_count_phandle_with_args(dev->of_node, >> + "thermal-sensors", >> + "#thermal-sensor-cells"); >> + if (sensor->count <= 0) >> + return -EINVAL; >> + >> + sensor->sensors = devm_kmalloc_array(dev, sensor->count, >> + sizeof(*sensor->sensors), >> + GFP_KERNEL); >> + if (!sensor->sensors) >> + return -ENOMEM; >> + >> + for (i = 0; i < sensor->count; i++) { >> + ret = of_parse_phandle_with_args(dev->of_node, >> + "thermal-sensors", >> + "#thermal-sensor-cells", >> + i, >> + &args); >> + if (ret) >> + return ret; >> + >> + ret = register_virtual_sensor(sensor, args, i); >> + if (ret) >> + return ret; >> + } >> + >> + ret = of_property_read_u32(dev->of_node, "type", &type); > More a question for the binding, butthis should probably be something > more specific than 'type', like 'aggregation-function'. > >> + if (ret) >> + return ret; >> + >> + switch (type) { >> + case VIRTUAL_SENSOR_MAX: >> + ops = &virtual_sensor_max_ops; >> + break; >> + case VIRTUAL_SENSOR_MIN: >> + ops = &virtual_sensor_min_ops; >> + break; >> + case VIRTUAL_SENSOR_AVG: >> + ops = &virtual_sensor_avg_ops; >> + break; >> + default: >> + return -EINVAL; >> + } >> + >> + sensor->tzd = devm_thermal_zone_of_sensor_register(dev, 0, sensor, ops); >> + if (IS_ERR(sensor->tzd)) >> + return PTR_ERR(sensor->tzd); >> + >> + platform_set_drvdata(pdev, sensor); >> + list_add(&sensor->node, &virtual_sensors); > If you also added the sensor to 'thermal_sensors' you could support virtual > sensors using virtual sensors, though it's not clear how useful that would be > in practice and it could raise issues with the initialization order. Unless if we found some use cases, I think we should not do that. As you mentioned, this would add some complexity to the initialization to handle it. > >> + >> + return 0; >> +} >> + >> +static int virtual_sensor_remove(struct platform_device *pdev) >> +{ >> + struct device *dev = &pdev->dev; >> + struct virtual_sensor *sensor; >> + >> + sensor = platform_get_drvdata(pdev); >> + list_del(&sensor->node); >> + >> + devm_thermal_zone_of_sensor_unregister(dev, sensor->tzd); >> + devm_kfree(dev, sensor->sensors); >> + devm_kfree(dev, sensor); > Are the above 3 statements really needed, shouldn't devm_* handle that > automagically? No, I will remove them. > >> + >> + return 0; >> +} >> + >> +static const struct of_device_id virtual_sensor_of_match[] = { >> + { >> + .compatible = "virtual,thermal-sensor", >> + }, >> + { >> + }, >> +}; >> +MODULE_DEVICE_TABLE(of, thermal_aggr_of_match); >> + >> +static struct platform_driver virtual_sensor = { >> + .probe = virtual_sensor_probe, >> + .remove = virtual_sensor_remove, >> + .driver = { >> + .name = "virtual-sensor", > I suggest to change it to 'virtual-thermal-sensor' since there might be > other types of virtual sensors. > >> + .of_match_table = virtual_sensor_of_match, >> + }, >> +}; >> + >> +/** >> + * thermal_virtual_sensor_register - registers a sensor that could by a virtual > s/by/be/ > >> + * sensor >> + * @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 > s/sensors/sensor/ > >> + * @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 register a thermal sensor to make it available for later >> + * usage by a virtual sensor. >> + * >> + * The thermal zone temperature is provided by the @get_temp function >> + * pointer. When called, it will have the private pointer @data back. >> + * >> + * 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 virtual_sensor_data *thermal_virtual_sensor_register( >> + struct device *dev, int sensor_id, void *data, >> + const struct thermal_zone_of_device_ops *ops) >> +{ >> + struct virtual_sensor_data *sensor_data; >> + >> + sensor_data = devm_kzalloc(dev, sizeof(*sensor_data), GFP_KERNEL); >> + if (!sensor_data) >> + return ERR_PTR(-ENOMEM); >> + >> + sensor_data->id = sensor_id; >> + sensor_data->sensor_data = data; >> + sensor_data->ops = ops; >> + >> + list_add(&sensor_data->node, &thermal_sensors); >> + >> + return sensor_data; >> +} >> +EXPORT_SYMBOL_GPL(thermal_virtual_sensor_register); >> + >> +/** >> + * thermal_virtual_sensor_unregister - unregisters a sensor >> + * @dev: a valid struct device pointer of a sensor device. >> + * @sensor_data: a pointer to struct virtual_sensor_data to unregister. >> + * >> + * This function removes the sensor from the list of available thermal sensors. >> + * If the sensor is in use, then the next call to .get_temp will return -ENODEV. >> + */ >> +void thermal_virtual_sensor_unregister(struct device *dev, >> + struct virtual_sensor_data *sensor_data) >> +{ >> + struct virtual_sensor_data *temp; > 'temp' might not be the best name in this context, since it's associated with > temperature. Maybe name it 'sd'? > >> + struct virtual_sensor *sensor; >> + int i; >> + >> + list_del(&sensor_data->node); >> + >> + list_for_each_entry(sensor, &virtual_sensors, node) { >> + for (i = 0; i < sensor->count; i++) { >> + temp = &sensor->sensors[i]; >> + if (temp->id == sensor_data->id && >> + temp->sensor_data == sensor_data->sensor_data) { >> + temp->ops = NULL; >> + } >> + } >> + } >> + devm_kfree(dev, sensor_data); > Does it actually make sense to allocate the memory with devm_kzalloc() if > it is explicitly freed here? No, I should not call devm_kfree here. I will remove it. Thanks, Alexandre > >> +} >> +EXPORT_SYMBOL_GPL(thermal_virtual_sensor_unregister); >> + >> +static void devm_thermal_virtual_sensor_release(struct device *dev, void *res) >> +{ >> + thermal_virtual_sensor_unregister(dev, >> + *(struct virtual_sensor_data **)res); >> +} >> + >> +static int devm_thermal_virtual_sensor_match(struct device *dev, void *res, >> + void *data) >> +{ >> + struct virtual_sensor_data **r = res; >> + >> + if (WARN_ON(!r || !*r)) >> + return 0; >> + >> + return *r == data; >> +} >> + >> + > delete one of the empty lines > >> +/** >> + * devm_thermal_virtual_sensor_register - Resource managed version of >> + * thermal_virtual_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 > s/sensors/sensor/ > >> + * @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 virtual_sensor_data, >> + * otherwise, it returns a corresponding ERR_PTR(). Caller must >> + * check the return value with help of IS_ERR() helper. >> + * Registered virtual_sensor_data device will automatically be >> + * released when device is unbounded. > s/unbounded/unbound/
diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig index 7a4ba50ba97d0..23dc903da2fc5 100644 --- a/drivers/thermal/Kconfig +++ b/drivers/thermal/Kconfig @@ -228,6 +228,14 @@ config THERMAL_MMIO register or shared memory, is a potential candidate to work with this driver. +config VIRTUAL_THERMAL + tristate "Generic virtual thermal sensor driver" + depends on THERMAL_OF || COMPILE_TEST + help + This option enables the generic thermal sensor aggregator. + This driver creates a thermal sensor that reads the hardware sensors + and aggregate the temperature. + config HISI_THERMAL tristate "Hisilicon thermal driver" depends on ARCH_HISI || COMPILE_TEST diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile index 9729a2b089919..76dfa1d61bfc5 100644 --- a/drivers/thermal/Makefile +++ b/drivers/thermal/Makefile @@ -60,3 +60,4 @@ obj-$(CONFIG_UNIPHIER_THERMAL) += uniphier_thermal.o obj-$(CONFIG_AMLOGIC_THERMAL) += amlogic_thermal.o obj-$(CONFIG_SPRD_THERMAL) += sprd_thermal.o obj-$(CONFIG_KHADAS_MCU_FAN_THERMAL) += khadas_mcu_fan.o +obj-$(CONFIG_VIRTUAL_THERMAL) += virtual_sensor.o diff --git a/drivers/thermal/virtual-sensor.h b/drivers/thermal/virtual-sensor.h new file mode 100644 index 0000000000000..e024d434856c7 --- /dev/null +++ b/drivers/thermal/virtual-sensor.h @@ -0,0 +1,51 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (c) 2021 BayLibre + */ + +#ifndef __THERMAL_VIRTUAL_SENSOR_H__ +#define __THERMAL_VIRTUAL_SENSOR_H__ + +struct virtual_sensor; +struct virtual_sensor_data; + +#ifdef CONFIG_VIRTUAL_THERMAL +struct virtual_sensor_data * +thermal_virtual_sensor_register(struct device *dev, int sensor_id, void *data, + const struct thermal_zone_of_device_ops *ops); +void thermal_virtual_sensor_unregister(struct device *dev, + struct virtual_sensor_data *sensor_data); +struct virtual_sensor_data * +devm_thermal_virtual_sensor_register(struct device *dev, int sensor_id, void *data, + const struct thermal_zone_of_device_ops *ops); + +void devm_thermal_virtual_sensor_unregister(struct device *dev, + struct virtual_sensor *sensor); +#else +static inline struct virtual_sensor_data * +thermal_virtual_sensor_register(struct device *dev, int sensor_id, void *data, + const struct thermal_zone_of_device_ops *ops) +{ + return ERR_PTR(-ENODEV); +} + +void thermal_virtual_sensor_unregister(struct device *dev, + struct virtual_sensor_data *sensor_data) +{ +} + +static inline struct virtual_sensor_data * +devm_thermal_virtual_sensor_register(struct device *dev, int sensor_id, void *data, + const struct thermal_zone_of_device_ops *ops) +{ + return ERR_PTR(-ENODEV); +} + +static inline +void devm_thermal_virtual_sensor_unregister(struct device *dev, + struct virtual_sensor *sensor) +{ +} +#endif + +#endif /* __THERMAL_VIRTUAL_SENSOR_H__ */ diff --git a/drivers/thermal/virtual_sensor.c b/drivers/thermal/virtual_sensor.c new file mode 100644 index 0000000000000..e5bb0ef9adb39 --- /dev/null +++ b/drivers/thermal/virtual_sensor.c @@ -0,0 +1,400 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2021 BayLibre + */ + +#include <linux/err.h> +#include <linux/export.h> +#include <linux/module.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 <dt-bindings/thermal/virtual-sensor.h> + +#include "virtual-sensor.h" + +struct virtual_sensor_data { + struct list_head node; + + /* sensor interface */ + int id; + void *sensor_data; + const struct thermal_zone_of_device_ops *ops; +}; + +struct virtual_sensor { + int count; + struct virtual_sensor_data *sensors; + struct thermal_zone_device *tzd; + + struct list_head node; +}; + +static LIST_HEAD(thermal_sensors); +static LIST_HEAD(virtual_sensors); + +static int virtual_sensor_get_temp_max(void *data, int *temperature) +{ + struct virtual_sensor *sensor = data; + int max_temp = INT_MIN; + int temp; + int i; + + for (i = 0; i < sensor->count; i++) { + struct virtual_sensor_data *hw_sensor; + + hw_sensor = &sensor->sensors[i]; + if (!hw_sensor->ops) + return -ENODEV; + + hw_sensor->ops->get_temp(hw_sensor->sensor_data, &temp); + max_temp = max(max_temp, temp); + } + + *temperature = max_temp; + + return 0; +} + +static const struct thermal_zone_of_device_ops virtual_sensor_max_ops = { + .get_temp = virtual_sensor_get_temp_max, +}; + +static int virtual_sensor_get_temp_min(void *data, int *temperature) +{ + struct virtual_sensor *sensor = data; + int min_temp = INT_MAX; + int temp; + int i; + + for (i = 0; i < sensor->count; i++) { + struct virtual_sensor_data *hw_sensor; + + hw_sensor = &sensor->sensors[i]; + if (!hw_sensor->ops) + return -ENODEV; + + hw_sensor->ops->get_temp(hw_sensor->sensor_data, &temp); + min_temp = min(min_temp, temp); + } + + *temperature = min_temp; + + return 0; +} + +static const struct thermal_zone_of_device_ops virtual_sensor_min_ops = { + .get_temp = virtual_sensor_get_temp_min, +}; + +static int do_avg(int val1, int val2) +{ + return ((val1) / 2) + ((val2) / 2) + (((val1) % 2 + (val2) % 2) / 2); +} + +static int virtual_sensor_get_temp_avg(void *data, int *temperature) +{ + struct virtual_sensor *sensor = data; + int avg_temp = 0; + int temp; + int i; + + for (i = 0; i < sensor->count; i++) { + struct virtual_sensor_data *hw_sensor; + + hw_sensor = &sensor->sensors[i]; + if (!hw_sensor->ops) + return -ENODEV; + + hw_sensor->ops->get_temp(hw_sensor->sensor_data, &temp); + avg_temp = do_avg(avg_temp, temp); + } + + *temperature = avg_temp; + + return 0; +} + +static const struct thermal_zone_of_device_ops virtual_sensor_avg_ops = { + .get_temp = virtual_sensor_get_temp_avg, +}; + +static int register_virtual_sensor(struct virtual_sensor *sensor, + struct of_phandle_args args, + int index) +{ + struct virtual_sensor_data *sensor_data; + int id; + + list_for_each_entry(sensor_data, &thermal_sensors, node) { + id = args.args_count ? args.args[0] : 0; + if (sensor_data->id == id) { + memcpy(&sensor->sensors[index], sensor_data, + sizeof(*sensor_data)); + return 0; + } + } + + return -ENODEV; +} + +static int virtual_sensor_probe(struct platform_device *pdev) +{ + const struct thermal_zone_of_device_ops *ops; + struct virtual_sensor *sensor; + struct device *dev = &pdev->dev; + struct of_phandle_args args; + u32 type; + int ret; + int i; + + sensor = devm_kzalloc(dev, sizeof(*sensor), GFP_KERNEL); + if (!sensor) + return -ENOMEM; + + sensor->count = of_count_phandle_with_args(dev->of_node, + "thermal-sensors", + "#thermal-sensor-cells"); + if (sensor->count <= 0) + return -EINVAL; + + sensor->sensors = devm_kmalloc_array(dev, sensor->count, + sizeof(*sensor->sensors), + GFP_KERNEL); + if (!sensor->sensors) + return -ENOMEM; + + for (i = 0; i < sensor->count; i++) { + ret = of_parse_phandle_with_args(dev->of_node, + "thermal-sensors", + "#thermal-sensor-cells", + i, + &args); + if (ret) + return ret; + + ret = register_virtual_sensor(sensor, args, i); + if (ret) + return ret; + } + + ret = of_property_read_u32(dev->of_node, "type", &type); + if (ret) + return ret; + + switch (type) { + case VIRTUAL_SENSOR_MAX: + ops = &virtual_sensor_max_ops; + break; + case VIRTUAL_SENSOR_MIN: + ops = &virtual_sensor_min_ops; + break; + case VIRTUAL_SENSOR_AVG: + ops = &virtual_sensor_avg_ops; + break; + default: + return -EINVAL; + } + + sensor->tzd = devm_thermal_zone_of_sensor_register(dev, 0, sensor, ops); + if (IS_ERR(sensor->tzd)) + return PTR_ERR(sensor->tzd); + + platform_set_drvdata(pdev, sensor); + list_add(&sensor->node, &virtual_sensors); + + return 0; +} + +static int virtual_sensor_remove(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct virtual_sensor *sensor; + + sensor = platform_get_drvdata(pdev); + list_del(&sensor->node); + + devm_thermal_zone_of_sensor_unregister(dev, sensor->tzd); + devm_kfree(dev, sensor->sensors); + devm_kfree(dev, sensor); + + return 0; +} + +static const struct of_device_id virtual_sensor_of_match[] = { + { + .compatible = "virtual,thermal-sensor", + }, + { + }, +}; +MODULE_DEVICE_TABLE(of, thermal_aggr_of_match); + +static struct platform_driver virtual_sensor = { + .probe = virtual_sensor_probe, + .remove = virtual_sensor_remove, + .driver = { + .name = "virtual-sensor", + .of_match_table = virtual_sensor_of_match, + }, +}; + +/** + * thermal_virtual_sensor_register - registers a sensor that could by a virtual + * sensor + * @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 register a thermal sensor to make it available for later + * usage by a virtual sensor. + * + * The thermal zone temperature is provided by the @get_temp function + * pointer. When called, it will have the private pointer @data back. + * + * 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 virtual_sensor_data *thermal_virtual_sensor_register( + struct device *dev, int sensor_id, void *data, + const struct thermal_zone_of_device_ops *ops) +{ + struct virtual_sensor_data *sensor_data; + + sensor_data = devm_kzalloc(dev, sizeof(*sensor_data), GFP_KERNEL); + if (!sensor_data) + return ERR_PTR(-ENOMEM); + + sensor_data->id = sensor_id; + sensor_data->sensor_data = data; + sensor_data->ops = ops; + + list_add(&sensor_data->node, &thermal_sensors); + + return sensor_data; +} +EXPORT_SYMBOL_GPL(thermal_virtual_sensor_register); + +/** + * thermal_virtual_sensor_unregister - unregisters a sensor + * @dev: a valid struct device pointer of a sensor device. + * @sensor_data: a pointer to struct virtual_sensor_data to unregister. + * + * This function removes the sensor from the list of available thermal sensors. + * If the sensor is in use, then the next call to .get_temp will return -ENODEV. + */ +void thermal_virtual_sensor_unregister(struct device *dev, + struct virtual_sensor_data *sensor_data) +{ + struct virtual_sensor_data *temp; + struct virtual_sensor *sensor; + int i; + + list_del(&sensor_data->node); + + list_for_each_entry(sensor, &virtual_sensors, node) { + for (i = 0; i < sensor->count; i++) { + temp = &sensor->sensors[i]; + if (temp->id == sensor_data->id && + temp->sensor_data == sensor_data->sensor_data) { + temp->ops = NULL; + } + } + } + devm_kfree(dev, sensor_data); +} +EXPORT_SYMBOL_GPL(thermal_virtual_sensor_unregister); + +static void devm_thermal_virtual_sensor_release(struct device *dev, void *res) +{ + thermal_virtual_sensor_unregister(dev, + *(struct virtual_sensor_data **)res); +} + +static int devm_thermal_virtual_sensor_match(struct device *dev, void *res, + void *data) +{ + struct virtual_sensor_data **r = res; + + if (WARN_ON(!r || !*r)) + return 0; + + return *r == data; +} + + +/** + * devm_thermal_virtual_sensor_register - Resource managed version of + * thermal_virtual_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 virtual_sensor_data, + * otherwise, it returns a corresponding ERR_PTR(). Caller must + * check the return value with help of IS_ERR() helper. + * Registered virtual_sensor_data device will automatically be + * released when device is unbounded. + */ +struct virtual_sensor_data *devm_thermal_virtual_sensor_register( + struct device *dev, int sensor_id, + void *data, const struct thermal_zone_of_device_ops *ops) +{ + struct virtual_sensor_data **ptr, *sensor_data; + + ptr = devres_alloc(devm_thermal_virtual_sensor_release, sizeof(*ptr), + GFP_KERNEL); + if (!ptr) + return ERR_PTR(-ENOMEM); + + sensor_data = thermal_virtual_sensor_register(dev, sensor_id, data, ops); + if (IS_ERR(sensor_data)) { + devres_free(ptr); + return sensor_data; + } + + *ptr = sensor_data; + devres_add(dev, ptr); + + return sensor_data; +} +EXPORT_SYMBOL_GPL(devm_thermal_virtual_sensor_register); + +/** + * devm_thermal_virtual_sensor_unregister - Resource managed version of + * thermal_virtual_sensor_unregister(). + * @dev: Device for which resource was allocated. + * @sensor: a pointer to struct thermal_zone_device where the sensor is registered. + * + * This function removes the sensor from the list of sensors registered with + * devm_thermal_virtual_sensor_register() API. + * Normally this function will not need to be called and the resource + * management code will ensure that the resource is freed. + */ +void devm_thermal_virtual_sensor_unregister(struct device *dev, + struct virtual_sensor *sensor) +{ + WARN_ON(devres_release(dev, devm_thermal_virtual_sensor_release, + devm_thermal_virtual_sensor_match, sensor)); +} +EXPORT_SYMBOL_GPL(devm_thermal_virtual_sensor_unregister); + +module_platform_driver(virtual_sensor); +MODULE_AUTHOR("Alexandre Bailon <abailon@baylibre.com>"); +MODULE_DESCRIPTION("Virtual thermal sensor"); +MODULE_LICENSE("GPL v2");
This adds a virtual thermal sensor that reads temperature from hardware sensor and return an aggregated temperature. Currently, this only return the max temperature. Signed-off-by: Alexandre Bailon <abailon@baylibre.com> --- drivers/thermal/Kconfig | 8 + drivers/thermal/Makefile | 1 + drivers/thermal/virtual-sensor.h | 51 ++++ drivers/thermal/virtual_sensor.c | 400 +++++++++++++++++++++++++++++++ 4 files changed, 460 insertions(+) create mode 100644 drivers/thermal/virtual-sensor.h create mode 100644 drivers/thermal/virtual_sensor.c