Hi Pin-yen,
Hi Alexandre, On Thu, Apr 11, 2024 at 4:34 PM Alexandre Bailon <abailon@xxxxxxxxxxxx> wrote:This adds support of multi sensors to thermal. Currently, this only support the get_temp operation. This returns an average temperature of all the sensors. If defined, a coefficient is applied to the value read from the sensor before computing the average. Signed-off-by: Alexandre Bailon <abailon@xxxxxxxxxxxx> --- drivers/thermal/Makefile | 1 + drivers/thermal/thermal_core.h | 7 ++ drivers/thermal/thermal_multi.c | 178 ++++++++++++++++++++++++++++++++ 3 files changed, 186 insertions(+) create mode 100644 drivers/thermal/thermal_multi.c diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile index c934cab309ae..757289a406f7 100644 --- a/drivers/thermal/Makefile +++ b/drivers/thermal/Makefile @@ -6,6 +6,7 @@ CFLAGS_thermal_core.o := -I$(src) obj-$(CONFIG_THERMAL) += thermal_sys.o thermal_sys-y += thermal_core.o thermal_sysfs.o thermal_sys-y += thermal_trip.o thermal_helpers.o +thermal_sys-y += thermal_multi.o # netlink interface to manage the thermal framework thermal_sys-$(CONFIG_THERMAL_NETLINK) += thermal_netlink.o diff --git a/drivers/thermal/thermal_core.h b/drivers/thermal/thermal_core.h index 0a3b3ec5120b..26e83a5c8298 100644 --- a/drivers/thermal/thermal_core.h +++ b/drivers/thermal/thermal_core.h @@ -138,6 +138,13 @@ ssize_t weight_show(struct device *, struct device_attribute *, char *); ssize_t weight_store(struct device *, struct device_attribute *, const char *, size_t); +/* Multi sensors */ +int thermal_multi_sensor_validate_coeff(int *coeff, int count, int offset); +int thermal_multi_sensor_register(const char *name, + struct thermal_zone_device *sensor_tz, int coeff); +void thermal_multi_sensor_unregister(struct thermal_zone_device *sensor_tz); + + #ifdef CONFIG_THERMAL_STATISTICS void thermal_cooling_device_stats_update(struct thermal_cooling_device *cdev, unsigned long new_state); diff --git a/drivers/thermal/thermal_multi.c b/drivers/thermal/thermal_multi.c new file mode 100644 index 000000000000..a5a4f1f2d594 --- /dev/null +++ b/drivers/thermal/thermal_multi.c @@ -0,0 +1,178 @@ +// SPDX-License-Identifier: GPL-2.0 + +#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" + +struct sensor_interface { + struct thermal_zone_device *tz; + int coeff; + + struct list_head node; +}; + +struct multi_sensor_thermal_zone { + struct thermal_zone_device *tz; + struct mutex sensors_lock; + struct list_head sensors; + + struct list_head node; +}; + +static DEFINE_MUTEX(multi_tz_mutex); +static LIST_HEAD(multi_tz_list); + +#define TJ_MAX 120000 + +static int multi_sensor_get_temp(struct thermal_zone_device *tz, int *temp) +{ + struct multi_sensor_thermal_zone *multi_tz = tz->devdata; + struct sensor_interface *sensor; + int accumulated_temp = 0; + u32 accumulated_coeff;Should we initialize accumulated_coeff to 0 as well?
Yes, indeed, I will fix it.
+ int ret; + + mutex_lock(&multi_tz->sensors_lock); + + if (list_empty(&multi_tz->sensors)) { + mutex_unlock(&multi_tz->sensors_lock); + return -ENODEV; + } + + list_for_each_entry(sensor, &multi_tz->sensors, node) { + ret = thermal_zone_get_temp(sensor->tz, temp); + if (ret) { + mutex_unlock(&multi_tz->sensors_lock); + return ret; + } + + accumulated_temp += *temp * sensor->coeff; + accumulated_coeff += sensor->coeff; + } + + mutex_unlock(&multi_tz->sensors_lock); + + *temp = accumulated_temp / accumulated_coeff; + return ret; +} + +struct thermal_zone_device_ops multi_sensor_ops = { + .get_temp = multi_sensor_get_temp, +}; + +int thermal_multi_sensor_validate_coeff(int *coeff, int count, int offset) +{ + int max_accumulated_temp = 0; + int i; + + for (i = 0; i < count; i++) { + max_accumulated_temp += TJ_MAX * coeff[i]; + if (max_accumulated_temp < 0) + return -EOVERFLOW; + } + + max_accumulated_temp += offset; + return max_accumulated_temp < 0 ? -EOVERFLOW : 0; +} + +static struct thermal_zone_device *multi_sensor_tz_alloc(const char *name) +{ + struct thermal_zone_device *tz; + struct thermal_zone_params tzp = {}; + struct multi_sensor_thermal_zone *multi_tz; + + tz = thermal_zone_get_zone_by_name(name); + if (!IS_ERR(tz)) { + mutex_unlock(&multi_tz_mutex); + return tz; + } + + multi_tz = kzalloc(sizeof(*multi_tz), GFP_KERNEL); + if (!multi_tz) + return ERR_PTR(-ENOMEM); + mutex_init(&multi_tz->sensors_lock); + INIT_LIST_HEAD(&multi_tz->sensors); + + tzp.no_hwmon = true; + tzp.slope = 1; + tzp.offset = 0; + + tz = thermal_tripless_zone_device_register(name, multi_tz, + &multi_sensor_ops, &tzp); + if (IS_ERR(tz)) { + kfree(multi_tz); + } else { + multi_tz->tz = tz; + list_add(&multi_tz->node, &multi_tz_list); + } + + return tz; +} + +int thermal_multi_sensor_register(const char *name, + struct thermal_zone_device *sensor_tz, int coeff) +{ + struct thermal_zone_device *tz; + struct multi_sensor_thermal_zone *multi_tz; + struct sensor_interface *sensor; + + mutex_lock(&multi_tz_mutex); + + tz = multi_sensor_tz_alloc(name); + if (IS_ERR(tz)) { + mutex_unlock(&multi_tz_mutex); + return PTR_ERR(tz); + } + multi_tz = tz->devdata; + + sensor = kzalloc(sizeof(*sensor), GFP_KERNEL); + if (!sensor) { + mutex_unlock(&multi_tz_mutex); + return -ENOMEM; + } + + sensor->tz = sensor_tz; + sensor->coeff = coeff; + mutex_lock(&multi_tz->sensors_lock); + list_add(&sensor->node, &multi_tz->sensors); + mutex_unlock(&multi_tz->sensors_lock); + + thermal_zone_device_enable(tz); + + mutex_unlock(&multi_tz_mutex); + + return 0; +} + +void thermal_multi_sensor_unregister(struct thermal_zone_device *sensor_tz) +{ + struct multi_sensor_thermal_zone *multi_tz; + struct sensor_interface *sensor, *tmp; + + mutex_lock(&multi_tz_mutex); + list_for_each_entry(multi_tz, &multi_tz_list, node) { + mutex_lock(&multi_tz->sensors_lock); + list_for_each_entry_safe(sensor, tmp, &multi_tz->sensors, node) { + if (sensor->tz == sensor_tz) { + list_del(&sensor->node); + kfree(sensor); + break; + } + } + + if (list_empty(&multi_tz->sensors)) { + thermal_zone_device_unregister(multi_tz->tz); + mutex_unlock(&multi_tz->sensors_lock); + kfree(multi_tz); + } else { + mutex_unlock(&multi_tz->sensors_lock); + } + } + mutex_unlock(&multi_tz_mutex); +} -- 2.41.0By the way, may I know why min/max aggregation is dropped in this version? I thought that checking max temperature is the most direct approach to protect the hardware and the users from high temperature.
You are right. The main reason was device tree bindings. I was expecting getting this accepted first before adding max and min. Thanks, Alexandre
Best regards, Pin-yen
