[PATCH v1 2/3] iwlwifi: mvm: Populate trip table before registering thermal zone

From: Rafael J. Wysocki
Date: Wed Feb 07 2024 - 14:13:08 EST


From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>

The trip table in iwl_mvm_thermal_zone_register() is populated after
passing it to thermal_zone_device_register_with_trips(), so it may be
accessed (for instance, via sysfs) before it is ready.

To prevent that from happening, modify the function to populate the
trip table before calling thermal_zone_device_register_with_trips().

Also make the code use THERMAL_TEMP_INVALID as the "invalid temperature"
value which is also meaningful for the core.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
---
drivers/net/wireless/intel/iwlwifi/mvm/tt.c | 19 +++++++++----------
1 file changed, 9 insertions(+), 10 deletions(-)

Index: linux-pm/drivers/net/wireless/intel/iwlwifi/mvm/tt.c
===================================================================
--- linux-pm.orig/drivers/net/wireless/intel/iwlwifi/mvm/tt.c
+++ linux-pm/drivers/net/wireless/intel/iwlwifi/mvm/tt.c
@@ -575,7 +575,7 @@ int iwl_mvm_send_temp_report_ths_cmd(str

/* compress trips to cmd array, remove uninitialized values*/
for (i = 0; i < IWL_MAX_DTS_TRIPS; i++) {
- if (mvm->tz_device.trips[i].temperature != INT_MIN) {
+ if (mvm->tz_device.trips[i].temperature != THERMAL_TEMP_INVALID) {
cmd.thresholds[idx++] =
cpu_to_le16((s16)(mvm->tz_device.trips[i].temperature / 1000));
}
@@ -675,6 +675,14 @@ static void iwl_mvm_thermal_zone_registe
BUILD_BUG_ON(ARRAY_SIZE(name) >= THERMAL_NAME_LENGTH);

sprintf(name, "iwlwifi_%u", atomic_inc_return(&counter) & 0xFF);
+ /*
+ * 0 is a valid temperature,
+ * so initialize the array with S16_MIN which invalid temperature
+ */
+ for (i = 0 ; i < IWL_MAX_DTS_TRIPS; i++) {
+ mvm->tz_device.trips[i].temperature = THERMAL_TEMP_INVALID;
+ mvm->tz_device.trips[i].type = THERMAL_TRIP_PASSIVE;
+ }
mvm->tz_device.tzone = thermal_zone_device_register_with_trips(name,
mvm->tz_device.trips,
IWL_MAX_DTS_TRIPS,
@@ -693,15 +701,6 @@ static void iwl_mvm_thermal_zone_registe
if (ret) {
IWL_DEBUG_TEMP(mvm, "Failed to enable thermal zone\n");
thermal_zone_device_unregister(mvm->tz_device.tzone);
- return;
- }
-
- /* 0 is a valid temperature,
- * so initialize the array with S16_MIN which invalid temperature
- */
- for (i = 0 ; i < IWL_MAX_DTS_TRIPS; i++) {
- mvm->tz_device.trips[i].temperature = INT_MIN;
- mvm->tz_device.trips[i].type = THERMAL_TRIP_PASSIVE;
}
}