Message ID | 20240923100005.2532430-2-daniel.lezcano@linaro.org |
---|---|
State | New |
Headers | show |
Series | Add thermal user thresholds support | expand |
On Mon, Sep 23, 2024 at 12:00 PM Daniel Lezcano <daniel.lezcano@linaro.org> wrote: > > The user thresholds mechanism is a way to have the userspace to tell > the thermal framework to send a notification when a temperature limit > is crossed. There is no id, no hysteresis, just the temperature and > the direction of the limit crossing. That means we can be notified > when a threshold is crossed the way up only, or the way down only or > both ways. That allows to create hysteresis values if it is needed. > > A threshold can be added, deleted or flushed. The latter means all > thresholds belonging to a thermal zone will be deleted. > > When a threshold is added: > > - if the same threshold (temperature and direction) exists, an error > is returned > > - if a threshold is specified with the same temperature but a > different direction, the specified direction is added > > - if there is no threshold with the same temperature then it is > created > > When a threshold is deleted: > > - if the same threshold (temperature and direction) exists, it is > deleted > > - if a threshold is specified with the same temperature but a > different direction, the specified direction is removed > > - if there is no threshold with the same temperature, then an error > is returned > > When the threshold are flushed: > > - All thresholds related to a thermal zone are deleted > > When a threshold is crossed: > > - the userspace does not need to know which threshold(s) have been > crossed, it will be notified with the current temperature and the > previous temperature > > - if multiple thresholds have been crossed between two updates only > one notification will be send to the userspace, it is pointless to > send a notification per thresholds crossed as the userspace can > handle that easily when it has the temperature delta information > > Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> > --- > drivers/thermal/Makefile | 1 + > drivers/thermal/thermal_core.h | 2 + > drivers/thermal/thermal_thresholds.c | 229 +++++++++++++++++++++++++++ > drivers/thermal/thermal_thresholds.h | 19 +++ > include/linux/thermal.h | 3 + > include/uapi/linux/thermal.h | 2 + > 6 files changed, 256 insertions(+) > create mode 100644 drivers/thermal/thermal_thresholds.c > create mode 100644 drivers/thermal/thermal_thresholds.h > > diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile > index 41c4d56beb40..1e1559bb971e 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_thresholds.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 50b858aa173a..8f320d17d927 100644 > --- a/drivers/thermal/thermal_core.h > +++ b/drivers/thermal/thermal_core.h > @@ -13,6 +13,7 @@ > #include <linux/thermal.h> > > #include "thermal_netlink.h" > +#include "thermal_thresholds.h" > #include "thermal_debugfs.h" > > struct thermal_attr { > @@ -139,6 +140,7 @@ struct thermal_zone_device { > #ifdef CONFIG_THERMAL_DEBUGFS > struct thermal_debugfs *debugfs; > #endif > + struct list_head user_thresholds; > struct thermal_trip_desc trips[] __counted_by(num_trips); > }; > > diff --git a/drivers/thermal/thermal_thresholds.c b/drivers/thermal/thermal_thresholds.c > new file mode 100644 > index 000000000000..f33b6d5474d8 > --- /dev/null > +++ b/drivers/thermal/thermal_thresholds.c > @@ -0,0 +1,229 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * Copyright 2024 Linaro Limited > + * > + * Author: Daniel Lezcano <daniel.lezcano@linaro.org> > + * > + * Thermal thresholds > + */ > +#include <linux/list.h> > +#include <linux/list_sort.h> > +#include <linux/slab.h> > + > +#include "thermal_core.h" > +#include "thermal_thresholds.h" > + > +int thermal_thresholds_init(struct thermal_zone_device *tz) > +{ > + INIT_LIST_HEAD(&tz->user_thresholds); > + > + return 0; > +} > + > +void thermal_thresholds_flush(struct thermal_zone_device *tz) > +{ > + struct list_head *thresholds = &tz->user_thresholds; > + struct user_threshold *entry, *tmp; > + > + lockdep_assert_held(&tz->lock); > + > + list_for_each_entry_safe(entry, tmp, thresholds, list_node) { > + list_del(&entry->list_node); > + kfree(entry); > + } > + > + __thermal_zone_device_update(tz, THERMAL_TZ_FLUSH_THRESHOLDS); > +} > + > +void thermal_thresholds_exit(struct thermal_zone_device *tz) > +{ > + thermal_thresholds_flush(tz); > +} > + > +static int __thermal_thresholds_cmp(void *data, > + const struct list_head *l1, > + const struct list_head *l2) > +{ > + struct user_threshold *t1 = container_of(l1, struct user_threshold, list_node); > + struct user_threshold *t2 = container_of(l2, struct user_threshold, list_node); > + > + return t1->temperature - t2->temperature; > +} > + > +static struct user_threshold *__thermal_thresholds_find(const struct list_head *thresholds, > + int temperature) > +{ > + struct user_threshold *t; > + > + list_for_each_entry(t, thresholds, list_node) > + if (t->temperature == temperature) > + return t; > + > + return NULL; > +} > + > +static bool __thermal_threshold_is_crossed(struct user_threshold *threshold, int temperature, > + int last_temperature, int direction, > + int *low, int *high) > +{ > + > + if (temperature >= threshold->temperature) { > + if (threshold->temperature > *low && > + THERMAL_THRESHOLD_WAY_DOWN & threshold->direction) > + *low = threshold->temperature; > + > + if (last_temperature < threshold->temperature && > + threshold->direction & direction) > + return true; > + } else { > + if (threshold->temperature < *high && THERMAL_THRESHOLD_WAY_UP > + & threshold->direction) > + *high = threshold->temperature; > + > + if (last_temperature >= threshold->temperature && > + threshold->direction & direction) > + return true; > + } > + > + return false; > +} > + > +static bool thermal_thresholds_handle_raising(struct list_head *thresholds, int temperature, > + int last_temperature, int *low, int *high) > +{ > + struct user_threshold *t; > + > + list_for_each_entry(t, thresholds, list_node) { > + if (__thermal_threshold_is_crossed(t, temperature, last_temperature, > + THERMAL_THRESHOLD_WAY_UP, low, high)) > + return true; > + } > + > + return false; > +} > + > +static bool thermal_thresholds_handle_dropping(struct list_head *thresholds, int temperature, > + int last_temperature, int *low, int *high) > +{ > + struct user_threshold *t; > + > + list_for_each_entry_reverse(t, thresholds, list_node) { > + if (__thermal_threshold_is_crossed(t, temperature, last_temperature, > + THERMAL_THRESHOLD_WAY_DOWN, low, high)) > + return true; > + } > + > + return false; > +} > + > +void thermal_thresholds_handle(struct thermal_zone_device *tz, int *low, int *high) > +{ > + struct list_head *thresholds = &tz->user_thresholds; > + > + int temperature = tz->temperature; > + int last_temperature = tz->last_temperature; > + bool notify; > + > + lockdep_assert_held(&tz->lock); > + > + /* > + * We need a second update in order to detect a threshold being crossed > + */ > + if (last_temperature == THERMAL_TEMP_INVALID) > + return; > + > + /* > + * The temperature is stable, so obviously we can not have > + * crossed a threshold. > + */ > + if (last_temperature == temperature) > + return; > + > + /* > + * Since last update the temperature: > + * - increased : thresholds are crossed the way up > + * - decreased : thresholds are crossed the way down > + */ > + if (temperature > last_temperature) > + notify = thermal_thresholds_handle_raising(thresholds, temperature, > + last_temperature, low, high); > + else > + notify = thermal_thresholds_handle_dropping(thresholds, temperature, > + last_temperature, low, high); > + > + if (notify) > + pr_debug("A threshold has been crossed the way %s, with a temperature=%d, last_temperature=%d\n", > + temperature > last_temperature ? "up" : "down", temperature, last_temperature); > +} > + > +int thermal_thresholds_add(struct thermal_zone_device *tz, int temperature, int direction) > +{ > + struct list_head *thresholds = &tz->user_thresholds; > + struct user_threshold *t; > + > + lockdep_assert_held(&tz->lock); > + > + t = __thermal_thresholds_find(thresholds, temperature); > + if (t) { > + if (t->direction == direction) > + return -EEXIST; > + > + t->direction |= direction; > + } else { > + > + t = kmalloc(sizeof(*t), GFP_KERNEL); > + if (!t) > + return -ENOMEM; > + > + INIT_LIST_HEAD(&t->list_node); > + t->temperature = temperature; > + t->direction = direction; > + list_add(&t->list_node, thresholds); > + list_sort(NULL, thresholds, __thermal_thresholds_cmp); > + } > + > + __thermal_zone_device_update(tz, THERMAL_TZ_ADD_THRESHOLD); > + > + return 0; > +} > + > +int thermal_thresholds_delete(struct thermal_zone_device *tz, int temperature, int direction) > +{ > + struct list_head *thresholds = &tz->user_thresholds; > + struct user_threshold *t; > + > + lockdep_assert_held(&tz->lock); > + > + t = __thermal_thresholds_find(thresholds, temperature); > + if (!t) > + return -ENOENT; > + > + if (t->direction == direction) { > + list_del(&t->list_node); > + kfree(t); > + } else { > + t->direction &= ~direction; > + } > + > + __thermal_zone_device_update(tz, THERMAL_TZ_DEL_THRESHOLD); > + > + return 0; > +} > + > +int thermal_thresholds_for_each(struct thermal_zone_device *tz, > + int (*cb)(struct user_threshold *, void *arg), void *arg) > +{ > + struct list_head *thresholds = &tz->user_thresholds; > + struct user_threshold *entry; > + int ret; > + > + lockdep_assert_held(&tz->lock); > + > + list_for_each_entry(entry, thresholds, list_node) { > + ret = cb(entry, arg); > + if (ret) > + return ret; > + } > + > + return 0; > +} > diff --git a/drivers/thermal/thermal_thresholds.h b/drivers/thermal/thermal_thresholds.h > new file mode 100644 > index 000000000000..232f4e8089af > --- /dev/null > +++ b/drivers/thermal/thermal_thresholds.h > @@ -0,0 +1,19 @@ > +/* SPDX-License-Identifier: GPL-2.0 */ > +#ifndef __THERMAL_THRESHOLDS_H__ > +#define __THERMAL_THRESHOLDS_H__ > + > +struct user_threshold { > + struct list_head list_node; > + int temperature; > + int direction; > +}; > + > +int thermal_thresholds_init(struct thermal_zone_device *tz); > +void thermal_thresholds_exit(struct thermal_zone_device *tz); > +void thermal_thresholds_flush(struct thermal_zone_device *tz); > +void thermal_thresholds_handle(struct thermal_zone_device *tz, int *low, int *high); > +int thermal_thresholds_add(struct thermal_zone_device *tz, int temperature, int direction); > +int thermal_thresholds_delete(struct thermal_zone_device *tz, int temperature, int direction); > +int thermal_thresholds_for_each(struct thermal_zone_device *tz, > + int (*cb)(struct user_threshold *, void *arg), void *arg); > +#endif > diff --git a/include/linux/thermal.h b/include/linux/thermal.h > index 25ea8fe2313e..bcaa92732e14 100644 > --- a/include/linux/thermal.h > +++ b/include/linux/thermal.h > @@ -56,6 +56,9 @@ enum thermal_notify_event { > THERMAL_TZ_UNBIND_CDEV, /* Cooling dev is unbind from the thermal zone */ > THERMAL_INSTANCE_WEIGHT_CHANGED, /* Thermal instance weight changed */ > THERMAL_TZ_RESUME, /* Thermal zone is resuming after system sleep */ > + THERMAL_TZ_ADD_THRESHOLD, /* Threshold added */ > + THERMAL_TZ_DEL_THRESHOLD, /* Threshold deleted */ > + THERMAL_TZ_FLUSH_THRESHOLDS, /* All thresholds deleted */ > }; > > /** > diff --git a/include/uapi/linux/thermal.h b/include/uapi/linux/thermal.h > index fc78bf3aead7..3e7c1c2e71a7 100644 > --- a/include/uapi/linux/thermal.h > +++ b/include/uapi/linux/thermal.h > @@ -3,6 +3,8 @@ > #define _UAPI_LINUX_THERMAL_H > > #define THERMAL_NAME_LENGTH 20 > +#define THERMAL_THRESHOLD_WAY_UP 0x1 > +#define THERMAL_THRESHOLD_WAY_DOWN 0x2 It would be somewhat better to use BIT(0) and BIT(1) here IMO, but apart from that this patch and patch [2/6] are fine with me (even though my implementation of threshold crossing detection would be different). I still have questions regarding patch [3/6] though, but I'll need to take a fresh look at it tomorrow. > > enum thermal_device_mode { > THERMAL_DEVICE_DISABLED = 0, > -- > 2.43.0 >
Hi Rafael, On 02/10/2024 14:22, Rafael J. Wysocki wrote: > On Tue, Oct 1, 2024 at 9:57 PM Rafael J. Wysocki <rafael@kernel.org> wrote: >> >> On Mon, Sep 23, 2024 at 12:00 PM Daniel Lezcano >> <daniel.lezcano@linaro.org> wrote: >>> >>> The user thresholds mechanism is a way to have the userspace to tell >>> the thermal framework to send a notification when a temperature limit >>> is crossed. There is no id, no hysteresis, just the temperature and >>> the direction of the limit crossing. That means we can be notified >>> when a threshold is crossed the way up only, or the way down only or >>> both ways. That allows to create hysteresis values if it is needed. [ ... ] > I'm inclined to apply these 2 patches with the change mentioned above, > so that I can base my 6.13 work on them. I was expecting you to pick these two patches and do the modifications but I don't see them in your tree. Did I misunderstood your comment?
On 09/10/2024 17:59, Rafael J. Wysocki wrote: > Hi Daniel, > > On Wed, Oct 9, 2024 at 5:40 PM Daniel Lezcano <daniel.lezcano@linaro.org> wrote: >> >> >> Hi Rafael, >> >> On 02/10/2024 14:22, Rafael J. Wysocki wrote: >>> On Tue, Oct 1, 2024 at 9:57 PM Rafael J. Wysocki <rafael@kernel.org> wrote: >>>> >>>> On Mon, Sep 23, 2024 at 12:00 PM Daniel Lezcano >>>> <daniel.lezcano@linaro.org> wrote: >>>>> >>>>> The user thresholds mechanism is a way to have the userspace to tell >>>>> the thermal framework to send a notification when a temperature limit >>>>> is crossed. There is no id, no hysteresis, just the temperature and >>>>> the direction of the limit crossing. That means we can be notified >>>>> when a threshold is crossed the way up only, or the way down only or >>>>> both ways. That allows to create hysteresis values if it is needed. >> >> [ ... ] >> >> >>> I'm inclined to apply these 2 patches with the change mentioned above, >>> so that I can base my 6.13 work on them. >> >> I was expecting you to pick these two patches and do the modifications >> but I don't see them in your tree. Did I misunderstood your comment? > > That's still the plan, I've been waiting for you to respond and confirm. > > I gather that this is OK then. Yes, it is ;)
diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile index 41c4d56beb40..1e1559bb971e 100644 --- a/drivers/thermal/Makefile +++ b/drivers/thermal/Makefile @@ -6,6 +6,7 @@ CFLAGS_thermal_core.o := -I$(src) obj-$(CONFIG_THERMAL) += thermal_sys.o thermal_sys-y += thermal_core.o thermal_sysfs.o thermal_sys-y += thermal_trip.o thermal_helpers.o +thermal_sys-y += thermal_thresholds.o # netlink interface to manage the thermal framework thermal_sys-$(CONFIG_THERMAL_NETLINK) += thermal_netlink.o diff --git a/drivers/thermal/thermal_core.h b/drivers/thermal/thermal_core.h index 50b858aa173a..8f320d17d927 100644 --- a/drivers/thermal/thermal_core.h +++ b/drivers/thermal/thermal_core.h @@ -13,6 +13,7 @@ #include <linux/thermal.h> #include "thermal_netlink.h" +#include "thermal_thresholds.h" #include "thermal_debugfs.h" struct thermal_attr { @@ -139,6 +140,7 @@ struct thermal_zone_device { #ifdef CONFIG_THERMAL_DEBUGFS struct thermal_debugfs *debugfs; #endif + struct list_head user_thresholds; struct thermal_trip_desc trips[] __counted_by(num_trips); }; diff --git a/drivers/thermal/thermal_thresholds.c b/drivers/thermal/thermal_thresholds.c new file mode 100644 index 000000000000..f33b6d5474d8 --- /dev/null +++ b/drivers/thermal/thermal_thresholds.c @@ -0,0 +1,229 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright 2024 Linaro Limited + * + * Author: Daniel Lezcano <daniel.lezcano@linaro.org> + * + * Thermal thresholds + */ +#include <linux/list.h> +#include <linux/list_sort.h> +#include <linux/slab.h> + +#include "thermal_core.h" +#include "thermal_thresholds.h" + +int thermal_thresholds_init(struct thermal_zone_device *tz) +{ + INIT_LIST_HEAD(&tz->user_thresholds); + + return 0; +} + +void thermal_thresholds_flush(struct thermal_zone_device *tz) +{ + struct list_head *thresholds = &tz->user_thresholds; + struct user_threshold *entry, *tmp; + + lockdep_assert_held(&tz->lock); + + list_for_each_entry_safe(entry, tmp, thresholds, list_node) { + list_del(&entry->list_node); + kfree(entry); + } + + __thermal_zone_device_update(tz, THERMAL_TZ_FLUSH_THRESHOLDS); +} + +void thermal_thresholds_exit(struct thermal_zone_device *tz) +{ + thermal_thresholds_flush(tz); +} + +static int __thermal_thresholds_cmp(void *data, + const struct list_head *l1, + const struct list_head *l2) +{ + struct user_threshold *t1 = container_of(l1, struct user_threshold, list_node); + struct user_threshold *t2 = container_of(l2, struct user_threshold, list_node); + + return t1->temperature - t2->temperature; +} + +static struct user_threshold *__thermal_thresholds_find(const struct list_head *thresholds, + int temperature) +{ + struct user_threshold *t; + + list_for_each_entry(t, thresholds, list_node) + if (t->temperature == temperature) + return t; + + return NULL; +} + +static bool __thermal_threshold_is_crossed(struct user_threshold *threshold, int temperature, + int last_temperature, int direction, + int *low, int *high) +{ + + if (temperature >= threshold->temperature) { + if (threshold->temperature > *low && + THERMAL_THRESHOLD_WAY_DOWN & threshold->direction) + *low = threshold->temperature; + + if (last_temperature < threshold->temperature && + threshold->direction & direction) + return true; + } else { + if (threshold->temperature < *high && THERMAL_THRESHOLD_WAY_UP + & threshold->direction) + *high = threshold->temperature; + + if (last_temperature >= threshold->temperature && + threshold->direction & direction) + return true; + } + + return false; +} + +static bool thermal_thresholds_handle_raising(struct list_head *thresholds, int temperature, + int last_temperature, int *low, int *high) +{ + struct user_threshold *t; + + list_for_each_entry(t, thresholds, list_node) { + if (__thermal_threshold_is_crossed(t, temperature, last_temperature, + THERMAL_THRESHOLD_WAY_UP, low, high)) + return true; + } + + return false; +} + +static bool thermal_thresholds_handle_dropping(struct list_head *thresholds, int temperature, + int last_temperature, int *low, int *high) +{ + struct user_threshold *t; + + list_for_each_entry_reverse(t, thresholds, list_node) { + if (__thermal_threshold_is_crossed(t, temperature, last_temperature, + THERMAL_THRESHOLD_WAY_DOWN, low, high)) + return true; + } + + return false; +} + +void thermal_thresholds_handle(struct thermal_zone_device *tz, int *low, int *high) +{ + struct list_head *thresholds = &tz->user_thresholds; + + int temperature = tz->temperature; + int last_temperature = tz->last_temperature; + bool notify; + + lockdep_assert_held(&tz->lock); + + /* + * We need a second update in order to detect a threshold being crossed + */ + if (last_temperature == THERMAL_TEMP_INVALID) + return; + + /* + * The temperature is stable, so obviously we can not have + * crossed a threshold. + */ + if (last_temperature == temperature) + return; + + /* + * Since last update the temperature: + * - increased : thresholds are crossed the way up + * - decreased : thresholds are crossed the way down + */ + if (temperature > last_temperature) + notify = thermal_thresholds_handle_raising(thresholds, temperature, + last_temperature, low, high); + else + notify = thermal_thresholds_handle_dropping(thresholds, temperature, + last_temperature, low, high); + + if (notify) + pr_debug("A threshold has been crossed the way %s, with a temperature=%d, last_temperature=%d\n", + temperature > last_temperature ? "up" : "down", temperature, last_temperature); +} + +int thermal_thresholds_add(struct thermal_zone_device *tz, int temperature, int direction) +{ + struct list_head *thresholds = &tz->user_thresholds; + struct user_threshold *t; + + lockdep_assert_held(&tz->lock); + + t = __thermal_thresholds_find(thresholds, temperature); + if (t) { + if (t->direction == direction) + return -EEXIST; + + t->direction |= direction; + } else { + + t = kmalloc(sizeof(*t), GFP_KERNEL); + if (!t) + return -ENOMEM; + + INIT_LIST_HEAD(&t->list_node); + t->temperature = temperature; + t->direction = direction; + list_add(&t->list_node, thresholds); + list_sort(NULL, thresholds, __thermal_thresholds_cmp); + } + + __thermal_zone_device_update(tz, THERMAL_TZ_ADD_THRESHOLD); + + return 0; +} + +int thermal_thresholds_delete(struct thermal_zone_device *tz, int temperature, int direction) +{ + struct list_head *thresholds = &tz->user_thresholds; + struct user_threshold *t; + + lockdep_assert_held(&tz->lock); + + t = __thermal_thresholds_find(thresholds, temperature); + if (!t) + return -ENOENT; + + if (t->direction == direction) { + list_del(&t->list_node); + kfree(t); + } else { + t->direction &= ~direction; + } + + __thermal_zone_device_update(tz, THERMAL_TZ_DEL_THRESHOLD); + + return 0; +} + +int thermal_thresholds_for_each(struct thermal_zone_device *tz, + int (*cb)(struct user_threshold *, void *arg), void *arg) +{ + struct list_head *thresholds = &tz->user_thresholds; + struct user_threshold *entry; + int ret; + + lockdep_assert_held(&tz->lock); + + list_for_each_entry(entry, thresholds, list_node) { + ret = cb(entry, arg); + if (ret) + return ret; + } + + return 0; +} diff --git a/drivers/thermal/thermal_thresholds.h b/drivers/thermal/thermal_thresholds.h new file mode 100644 index 000000000000..232f4e8089af --- /dev/null +++ b/drivers/thermal/thermal_thresholds.h @@ -0,0 +1,19 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __THERMAL_THRESHOLDS_H__ +#define __THERMAL_THRESHOLDS_H__ + +struct user_threshold { + struct list_head list_node; + int temperature; + int direction; +}; + +int thermal_thresholds_init(struct thermal_zone_device *tz); +void thermal_thresholds_exit(struct thermal_zone_device *tz); +void thermal_thresholds_flush(struct thermal_zone_device *tz); +void thermal_thresholds_handle(struct thermal_zone_device *tz, int *low, int *high); +int thermal_thresholds_add(struct thermal_zone_device *tz, int temperature, int direction); +int thermal_thresholds_delete(struct thermal_zone_device *tz, int temperature, int direction); +int thermal_thresholds_for_each(struct thermal_zone_device *tz, + int (*cb)(struct user_threshold *, void *arg), void *arg); +#endif diff --git a/include/linux/thermal.h b/include/linux/thermal.h index 25ea8fe2313e..bcaa92732e14 100644 --- a/include/linux/thermal.h +++ b/include/linux/thermal.h @@ -56,6 +56,9 @@ enum thermal_notify_event { THERMAL_TZ_UNBIND_CDEV, /* Cooling dev is unbind from the thermal zone */ THERMAL_INSTANCE_WEIGHT_CHANGED, /* Thermal instance weight changed */ THERMAL_TZ_RESUME, /* Thermal zone is resuming after system sleep */ + THERMAL_TZ_ADD_THRESHOLD, /* Threshold added */ + THERMAL_TZ_DEL_THRESHOLD, /* Threshold deleted */ + THERMAL_TZ_FLUSH_THRESHOLDS, /* All thresholds deleted */ }; /** diff --git a/include/uapi/linux/thermal.h b/include/uapi/linux/thermal.h index fc78bf3aead7..3e7c1c2e71a7 100644 --- a/include/uapi/linux/thermal.h +++ b/include/uapi/linux/thermal.h @@ -3,6 +3,8 @@ #define _UAPI_LINUX_THERMAL_H #define THERMAL_NAME_LENGTH 20 +#define THERMAL_THRESHOLD_WAY_UP 0x1 +#define THERMAL_THRESHOLD_WAY_DOWN 0x2 enum thermal_device_mode { THERMAL_DEVICE_DISABLED = 0,
The user thresholds mechanism is a way to have the userspace to tell the thermal framework to send a notification when a temperature limit is crossed. There is no id, no hysteresis, just the temperature and the direction of the limit crossing. That means we can be notified when a threshold is crossed the way up only, or the way down only or both ways. That allows to create hysteresis values if it is needed. A threshold can be added, deleted or flushed. The latter means all thresholds belonging to a thermal zone will be deleted. When a threshold is added: - if the same threshold (temperature and direction) exists, an error is returned - if a threshold is specified with the same temperature but a different direction, the specified direction is added - if there is no threshold with the same temperature then it is created When a threshold is deleted: - if the same threshold (temperature and direction) exists, it is deleted - if a threshold is specified with the same temperature but a different direction, the specified direction is removed - if there is no threshold with the same temperature, then an error is returned When the threshold are flushed: - All thresholds related to a thermal zone are deleted When a threshold is crossed: - the userspace does not need to know which threshold(s) have been crossed, it will be notified with the current temperature and the previous temperature - if multiple thresholds have been crossed between two updates only one notification will be send to the userspace, it is pointless to send a notification per thresholds crossed as the userspace can handle that easily when it has the temperature delta information Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> --- drivers/thermal/Makefile | 1 + drivers/thermal/thermal_core.h | 2 + drivers/thermal/thermal_thresholds.c | 229 +++++++++++++++++++++++++++ drivers/thermal/thermal_thresholds.h | 19 +++ include/linux/thermal.h | 3 + include/uapi/linux/thermal.h | 2 + 6 files changed, 256 insertions(+) create mode 100644 drivers/thermal/thermal_thresholds.c create mode 100644 drivers/thermal/thermal_thresholds.h