Merge tag 'thermal-6.2-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull thermal control fixes from Rafael Wysocki:
 "Add locking to the Intel int340x thermal control driver to prevent its
  thermal zone callbacks from racing with firmware-induced thermal trip
  point updates (Srinivas Pandruvada, Rafael Wysocki)"

* tag 'thermal-6.2-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  thermal: intel: int340x: Add locking to int340x_thermal_get_trip_type()
  thermal: intel: int340x: Protect trip temperature from concurrent updates

2 files changed, 23 insertions, 6 deletions

diff --git a/drivers/thermal/intel/int340x_thermal/int340x_thermal_zone.c b/drivers/thermal/intel/int340x_thermal/int340x_thermal_zone.c
index 62c0aa5d0783..0a4eaa307156 100644
--- a/drivers/thermal/intel/int340x_thermal/int340x_thermal_zone.c
+++ b/drivers/thermal/intel/int340x_thermal/int340x_thermal_zone.c
@@ -44,11 +44,13 @@ static int int340x_thermal_get_trip_temp(struct thermal_zone_device *zone,
 					 int trip, int *temp)
 {
 	struct int34x_thermal_zone *d = zone->devdata;
-	int i;
+	int i, ret = 0;
 
 	if (d->override_ops && d->override_ops->get_trip_temp)
 		return d->override_ops->get_trip_temp(zone, trip, temp);
 
+	mutex_lock(&d->trip_mutex);
+
 	if (trip < d->aux_trip_nr)
 		*temp = d->aux_trips[trip];
 	else if (trip == d->crt_trip_id)
@@ -66,10 +68,12 @@ static int int340x_thermal_get_trip_temp(struct thermal_zone_device *zone,
 			}
 		}
 		if (i == INT340X_THERMAL_MAX_ACT_TRIP_COUNT)
-			return -EINVAL;
+			ret = -EINVAL;
 	}
 
-	return 0;
+	mutex_unlock(&d->trip_mutex);
+
+	return ret;
 }
 
 static int int340x_thermal_get_trip_type(struct thermal_zone_device *zone,
@@ -77,11 +81,13 @@ static int int340x_thermal_get_trip_type(struct thermal_zone_device *zone,
 					 enum thermal_trip_type *type)
 {
 	struct int34x_thermal_zone *d = zone->devdata;
-	int i;
+	int i, ret = 0;
 
 	if (d->override_ops && d->override_ops->get_trip_type)
 		return d->override_ops->get_trip_type(zone, trip, type);
 
+	mutex_lock(&d->trip_mutex);
+
 	if (trip < d->aux_trip_nr)
 		*type = THERMAL_TRIP_PASSIVE;
 	else if (trip == d->crt_trip_id)
@@ -99,10 +105,12 @@ static int int340x_thermal_get_trip_type(struct thermal_zone_device *zone,
 			}
 		}
 		if (i == INT340X_THERMAL_MAX_ACT_TRIP_COUNT)
-			return -EINVAL;
+			ret = -EINVAL;
 	}
 
-	return 0;
+	mutex_unlock(&d->trip_mutex);
+
+	return ret;
 }
 
 static int int340x_thermal_set_trip_temp(struct thermal_zone_device *zone,
@@ -180,6 +188,8 @@ int int340x_thermal_read_trips(struct int34x_thermal_zone *int34x_zone)
 	int trip_cnt = int34x_zone->aux_trip_nr;
 	int i;
 
+	mutex_lock(&int34x_zone->trip_mutex);
+
 	int34x_zone->crt_trip_id = -1;
 	if (!int340x_thermal_get_trip_config(int34x_zone->adev->handle, "_CRT",
 					     &int34x_zone->crt_temp))
@@ -207,6 +217,8 @@ int int340x_thermal_read_trips(struct int34x_thermal_zone *int34x_zone)
 		int34x_zone->act_trips[i].valid = true;
 	}
 
+	mutex_unlock(&int34x_zone->trip_mutex);
+
 	return trip_cnt;
 }
 EXPORT_SYMBOL_GPL(int340x_thermal_read_trips);
@@ -230,6 +242,8 @@ struct int34x_thermal_zone *int340x_thermal_zone_add(struct acpi_device *adev,
 	if (!int34x_thermal_zone)
 		return ERR_PTR(-ENOMEM);
 
+	mutex_init(&int34x_thermal_zone->trip_mutex);
+
 	int34x_thermal_zone->adev = adev;
 	int34x_thermal_zone->override_ops = override_ops;
 
@@ -281,6 +295,7 @@ err_thermal_zone:
 	acpi_lpat_free_conversion_table(int34x_thermal_zone->lpat_table);
 	kfree(int34x_thermal_zone->aux_trips);
 err_trip_alloc:
+	mutex_destroy(&int34x_thermal_zone->trip_mutex);
 	kfree(int34x_thermal_zone);
 	return ERR_PTR(ret);
 }
@@ -292,6 +307,7 @@ void int340x_thermal_zone_remove(struct int34x_thermal_zone
 	thermal_zone_device_unregister(int34x_thermal_zone->zone);
 	acpi_lpat_free_conversion_table(int34x_thermal_zone->lpat_table);
 	kfree(int34x_thermal_zone->aux_trips);
+	mutex_destroy(&int34x_thermal_zone->trip_mutex);
 	kfree(int34x_thermal_zone);
 }
 EXPORT_SYMBOL_GPL(int340x_thermal_zone_remove);
diff --git a/drivers/thermal/intel/int340x_thermal/int340x_thermal_zone.h b/drivers/thermal/intel/int340x_thermal/int340x_thermal_zone.h
index 3b4971df1b33..8f9872afd0d3 100644
--- a/drivers/thermal/intel/int340x_thermal/int340x_thermal_zone.h
+++ b/drivers/thermal/intel/int340x_thermal/int340x_thermal_zone.h
@@ -32,6 +32,7 @@ struct int34x_thermal_zone {
 	struct thermal_zone_device_ops *override_ops;
 	void *priv_data;
 	struct acpi_lpat_conversion_table *lpat_table;
+	struct mutex trip_mutex;
 };
 
 struct int34x_thermal_zone *int340x_thermal_zone_add(struct acpi_device *,