[PATCH v3.1 6/8] ACPI: thermal: Use trip point table to register thermal zones

Rafael J. Wysocki
2023-07-25T18:12:10Z

Make the ACPI thermal driver use thermal_zone_device_register_with_trips()
to register its thermal zones.

For this purpose, make it create a trip point table and pass it to
thermal_zone_device_register_with_trips() as an argument and use the
struct thermal_trip_ref introduced previously to connect the generic
thermal trip structures to the internal data structures representing
trip points in the driver.

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

This is a bug-fix update that doesn't affect any other patches in the series,
so sending it separately as v3.1.

v3 -> v3.1:
* Do not pass THERMAL_TEMP_INVALID to acpi_thermal_trip_update_temp()
in acpi_thermal_check_fn().

v2 -> v3:
* Fix error code path memory leak in acpi_thermal_register_thermal_zone().
* Notice that the critical and hot trips never change after initialization,
so don't add struct thermal_trip_ref to any of them.

v1 -> v2:
* Use thermal_zone_device_lock()/thermal_zone_device_unlock() in
acpi_thermal_check_fn() explicitly and call __thermal_zone_device_update()
from there without unlocking the thermal zone.
* Export __thermal_zone_device_update() to modules (so it can be called by
the ACPI thermal code).

---
drivers/acpi/thermal.c | 107 ++++++++++++++++++++++++++++++++++++++---
drivers/thermal/thermal_core.c | 1
include/linux/thermal.h | 2
3 files changed, 103 insertions(+), 7 deletions(-)

Index: linux-pm/drivers/acpi/thermal.c
===================================================================
--- linux-pm.orig/drivers/acpi/thermal.c
+++ linux-pm/drivers/acpi/thermal.c
@@ -107,6 +107,7 @@ struct acpi_thermal_hot {
};

struct acpi_thermal_passive {
+ struct thermal_trip_ref trip_ref;
struct acpi_handle_list devices;
unsigned long temperature;
unsigned long tc1;
@@ -116,6 +117,7 @@ struct acpi_thermal_passive {
};

struct acpi_thermal_active {
+ struct thermal_trip_ref trip_ref;
struct acpi_handle_list devices;
unsigned long temperature;
bool valid;
@@ -137,6 +139,7 @@ struct acpi_thermal {
unsigned long polling_frequency;
volatile u8 zombie;
struct acpi_thermal_trips trips;
+ struct thermal_trip *trip_table;
struct acpi_handle_list devices;
struct thermal_zone_device *thermal_zone;
int kelvin_offset; /* in millidegrees */
@@ -190,6 +193,14 @@ static int acpi_thermal_get_polling_freq
return 0;
}

+static void acpi_thermal_trip_update_temp(struct acpi_thermal *tz,
+ struct thermal_trip *trip,
+ long temperature)
+{
+ trip->temperature = deci_kelvin_to_millicelsius_with_offset(temperature,
+ tz->kelvin_offset);
+}
+
static void __acpi_thermal_trips_update(struct acpi_thermal *tz, int flag)
{
acpi_status status;
@@ -756,6 +767,7 @@ static void acpi_thermal_zone_sysfs_remo

static int acpi_thermal_register_thermal_zone(struct acpi_thermal *tz)
{
+ struct thermal_trip *trip;
int passive_delay = 0;
int trip_count = 0;
int result;
@@ -776,12 +788,54 @@ static int acpi_thermal_register_thermal
for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE && tz->trips.active[i].valid; i++)
trip_count++;

- tz->thermal_zone = thermal_zone_device_register("acpitz", trip_count, 0,
- tz, &acpi_thermal_zone_ops,
- NULL, passive_delay,
- tz->polling_frequency * 100);
- if (IS_ERR(tz->thermal_zone))
- return -ENODEV;
+ trip = kcalloc(trip_count, sizeof(*trip), GFP_KERNEL);
+ if (!trip)
+ return -ENOMEM;
+
+ tz->trip_table = trip;
+
+ if (tz->trips.critical.valid) {
+ trip->type = THERMAL_TRIP_CRITICAL;
+ acpi_thermal_trip_update_temp(tz, trip,
+ tz->trips.critical.temperature);
+ trip++;
+ }
+
+ if (tz->trips.hot.valid) {
+ trip->type = THERMAL_TRIP_HOT;
+ acpi_thermal_trip_update_temp(tz, trip,
+ tz->trips.hot.temperature);
+ trip++;
+ }
+
+ if (tz->trips.passive.valid) {
+ trip->type = THERMAL_TRIP_PASSIVE;
+ acpi_thermal_trip_update_temp(tz, trip,
+ tz->trips.passive.temperature);
+ trip->driver_ref = &tz->trips.passive.trip_ref;
+ trip++;
+ }
+
+ for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE && tz->trips.active[i].valid; i++) {
+ trip->type = THERMAL_TRIP_ACTIVE;
+ acpi_thermal_trip_update_temp(tz, trip,
+ tz->trips.active[i].temperature);
+ trip->driver_ref = &tz->trips.active[i].trip_ref;
+ trip++;
+ }
+
+ tz->thermal_zone = thermal_zone_device_register_with_trips("acpitz",
+ tz->trip_table,
+ trip_count,
+ 0, tz,
+ &acpi_thermal_zone_ops,
+ NULL,
+ passive_delay,
+ tz->polling_frequency * 100);
+ if (IS_ERR(tz->thermal_zone)) {
+ result = PTR_ERR(tz->thermal_zone);
+ goto free_trip_table;
+ }

result = acpi_thermal_zone_sysfs_add(tz);
if (result)
@@ -809,6 +863,8 @@ remove_links:
acpi_thermal_zone_sysfs_remove(tz);
unregister_tzd:
thermal_zone_device_unregister(tz->thermal_zone);
+free_trip_table:
+ kfree(tz->trip_table);

return result;
}
@@ -817,6 +873,7 @@ static void acpi_thermal_unregister_ther
{
acpi_thermal_zone_sysfs_remove(tz);
thermal_zone_device_unregister(tz->thermal_zone);
+ kfree(tz->trip_table);
tz->thermal_zone = NULL;
acpi_bus_detach_private_data(tz->device->handle);
}
@@ -950,6 +1007,8 @@ static void acpi_thermal_check_fn(struct
{
struct acpi_thermal *tz = container_of(work, struct acpi_thermal,
thermal_check_work);
+ struct thermal_trip *trip;
+ int i;

/*
* In general, it is not sufficient to check the pending bit, because
@@ -964,7 +1023,41 @@ static void acpi_thermal_check_fn(struct

mutex_lock(&tz->thermal_check_lock);

- thermal_zone_device_update(tz->thermal_zone, THERMAL_EVENT_UNSPECIFIED);
+ thermal_zone_device_lock(tz->thermal_zone);
+
+ trip = tz->trips.passive.trip_ref.trip;
+ if (trip) {
+ /*
+ * This means that the passive trip was valid initially, so
+ * update its temperature in case it has changed or the trip
+ * has become invalid.
+ */
+ if (tz->trips.passive.valid)
+ acpi_thermal_trip_update_temp(tz, trip,
+ tz->trips.passive.temperature);
+ else
+ trip->temperature = THERMAL_TEMP_INVALID;
+ }
+
+ for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++) {
+ trip = tz->trips.active[i].trip_ref.trip;
+ if (trip) {
+ /*
+ * This means that the active trip #i was valid
+ * initially, so update its temperature in case it has
+ * changed or the trip has become invalid.
+ */
+ if (tz->trips.active[i].valid)
+ acpi_thermal_trip_update_temp(tz, trip,
+ tz->trips.active[i].temperature);
+ else
+ trip->temperature = THERMAL_TEMP_INVALID;
+ }
+ }
+
+ __thermal_zone_device_update(tz->thermal_zone, THERMAL_EVENT_UNSPECIFIED);
+
+ thermal_zone_device_unlock(tz->thermal_zone);

refcount_inc(&tz->thermal_check_count);

Index: linux-pm/drivers/thermal/thermal_core.c
===================================================================
--- linux-pm.orig/drivers/thermal/thermal_core.c
+++ linux-pm/drivers/thermal/thermal_core.c
@@ -429,6 +429,7 @@ void __thermal_zone_device_update(struct

monitor_thermal_zone(tz);
}
+EXPORT_SYMBOL_GPL(__thermal_zone_device_update);

static int thermal_zone_device_set_mode(struct thermal_zone_device *tz,
enum thermal_device_mode mode)
Index: linux-pm/include/linux/thermal.h
===================================================================
--- linux-pm.orig/include/linux/thermal.h
+++ linux-pm/include/linux/thermal.h
@@ -334,6 +334,8 @@ int thermal_zone_bind_cooling_device(str
unsigned int);
int thermal_zone_unbind_cooling_device(struct thermal_zone_device *, int,
struct thermal_cooling_device *);
+void __thermal_zone_device_update(struct thermal_zone_device *,
+ enum thermal_notify_event);
void thermal_zone_device_update(struct thermal_zone_device *,
enum thermal_notify_event);
void thermal_zone_device_lock(struct thermal_zone_device *tz);