Re: [PATCH v1] thermal: trip: Send trip change notifications on all trip updates

Daniel Lezcano <daniel.lezcano@xxxxxxxxxx> · Wed, 6 Dec 2023 15:38:50 +0100

Hi Rafael,

On 05/12/2023 20:18, Rafael J. Wysocki wrote:
From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>

The _store callbacks of the trip point temperature and hysteresis sysfs
attributes invoke thermal_notify_tz_trip_change() to send a notification
regarding the trip point change, but when trip points are updated by the
platform firmware, trip point change notifications are not sent.

To make the behavior after a trip point change more consistent,
modify all of the 3 places where trip point temperature is updated
to use a new function called thermal_zone_set_trip_temp() for this
purpose and make that function call thermal_notify_tz_trip_change().

Note that trip point hysteresis can only be updated via sysfs and
trip_point_hyst_store() calls thermal_notify_tz_trip_change() already,
so this code path need not be changed.

Why the ACPI driver is not calling thermal_zone_device_update() after 
changing the trip point like the other drivers?

It would make sense to have the thermal framework to be notified about 
this change and check if there is a trip violation, no ?


Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
---

Depends on https://lore.kernel.org/linux-pm/12337662.O9o76ZdvQC@kreacher/

---
  drivers/acpi/thermal.c                                       |    7 +++--
  drivers/thermal/intel/int340x_thermal/int340x_thermal_zone.c |    8 +++---
  drivers/thermal/thermal_sysfs.c                              |    4 +--
  drivers/thermal/thermal_trip.c                               |   14 ++++++++++-
  include/linux/thermal.h                                      |    2 +
  5 files changed, 27 insertions(+), 8 deletions(-)

Index: linux-pm/drivers/thermal/thermal_sysfs.c
===================================================================

--- linux-pm.orig/drivers/thermal/thermal_sysfs.c
+++ linux-pm/drivers/thermal/thermal_sysfs.c
@@ -146,9 +146,9 @@ trip_point_temp_store(struct device *dev
  				goto unlock;
  		}
  
-		trip->temperature = temp;
+		thermal_zone_set_trip_temp(tz, trip, temp);
  
-		thermal_zone_trip_updated(tz, trip);
+		__thermal_zone_device_update(tz, THERMAL_TRIP_CHANGED);
  	}
  
  unlock:
Index: linux-pm/drivers/thermal/thermal_trip.c
===================================================================
--- linux-pm.orig/drivers/thermal/thermal_trip.c
+++ linux-pm/drivers/thermal/thermal_trip.c
@@ -152,7 +152,6 @@ int thermal_zone_trip_id(struct thermal_
  	 */
  	return trip - tz->trips;
  }
-
  void thermal_zone_trip_updated(struct thermal_zone_device *tz,
  			       const struct thermal_trip *trip)
  {
@@ -161,3 +160,16 @@ void thermal_zone_trip_updated(struct th
  				      trip->hysteresis);
  	__thermal_zone_device_update(tz, THERMAL_TRIP_CHANGED);
  }
+
+void thermal_zone_set_trip_temp(struct thermal_zone_device *tz,
+				struct thermal_trip *trip, int temp)
+{
+	if (trip->temperature == temp)
+		return;
+
+	trip->temperature = temp;
+	thermal_notify_tz_trip_change(tz->id, thermal_zone_trip_id(tz, trip),
+				      trip->type, trip->temperature,
+				      trip->hysteresis);
+}
+EXPORT_SYMBOL_GPL(thermal_zone_set_trip_temp);
Index: linux-pm/include/linux/thermal.h
===================================================================
--- linux-pm.orig/include/linux/thermal.h
+++ linux-pm/include/linux/thermal.h
@@ -289,6 +289,8 @@ int thermal_zone_for_each_trip(struct th
  			       int (*cb)(struct thermal_trip *, void *),
  			       void *data);
  int thermal_zone_get_num_trips(struct thermal_zone_device *tz);
+void thermal_zone_set_trip_temp(struct thermal_zone_device *tz,
+				struct thermal_trip *trip, int temp);
  
  int thermal_zone_get_crit_temp(struct thermal_zone_device *tz, int *temp);
  
Index: linux-pm/drivers/acpi/thermal.c
===================================================================
--- linux-pm.orig/drivers/acpi/thermal.c
+++ linux-pm/drivers/acpi/thermal.c
@@ -294,6 +294,7 @@ static int acpi_thermal_adjust_trip(stru
  	struct acpi_thermal_trip *acpi_trip = trip->priv;
  	struct adjust_trip_data *atd = data;
  	struct acpi_thermal *tz = atd->tz;
+	int temp;
  
  	if (!acpi_trip || !acpi_thermal_trip_valid(acpi_trip))
  		return 0;
@@ -304,9 +305,11 @@ static int acpi_thermal_adjust_trip(stru
  		acpi_thermal_update_trip_devices(tz, trip);
  
  	if (acpi_thermal_trip_valid(acpi_trip))
-		trip->temperature = acpi_thermal_temp(tz, acpi_trip->temp_dk);
+		temp = acpi_thermal_temp(tz, acpi_trip->temp_dk);
  	else
-		trip->temperature = THERMAL_TEMP_INVALID;
+		temp = THERMAL_TEMP_INVALID;
+
+	thermal_zone_set_trip_temp(tz->thermal_zone, trip, temp);
  
  	return 0;
  }
Index: linux-pm/drivers/thermal/intel/int340x_thermal/int340x_thermal_zone.c
===================================================================
--- linux-pm.orig/drivers/thermal/intel/int340x_thermal/int340x_thermal_zone.c
+++ linux-pm/drivers/thermal/intel/int340x_thermal/int340x_thermal_zone.c
@@ -225,7 +225,8 @@ EXPORT_SYMBOL_GPL(int340x_thermal_zone_r
  
  static int int340x_update_one_trip(struct thermal_trip *trip, void *arg)
  {
-	struct acpi_device *zone_adev = arg;
+	struct int34x_thermal_zone *int34x_zone = arg;
+	struct acpi_device *zone_adev = int34x_zone->adev;
  	int temp, err;
  
  	switch (trip->type) {
@@ -249,14 +250,15 @@ static int int340x_update_one_trip(struc
  	if (err)
  		temp = THERMAL_TEMP_INVALID;
  
-	trip->temperature = temp;
+	thermal_zone_set_trip_temp(int34x_zone->zone, trip, temp);
+
  	return 0;
  }
  
  void int340x_thermal_update_trips(struct int34x_thermal_zone *int34x_zone)
  {
  	thermal_zone_for_each_trip(int34x_zone->zone, int340x_update_one_trip,
-				   int34x_zone->adev);
+				   int34x_zone);
  }
  EXPORT_SYMBOL_GPL(int340x_thermal_update_trips);
  




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