Thermal: initialize thermal zone device correctly

[ Upstream commit bb431ba26c5cd0a17c941ca6c3a195a3a6d5d461 ]

After thermal zone device registered, as we have not read any
temperature before, thus tz->temperature should not be 0,
which actually means 0C, and thermal trend is not available.
In this case, we need specially handling for the first
thermal_zone_device_update().

Both thermal core framework and step_wise governor is
enhanced to handle this. And since the step_wise governor
is the only one that uses trends, so it's the only thermal
governor that needs to be updated.

CC: <stable@vger.kernel.org> #3.18+
Tested-by: Manuel Krause <manuelkrause@netscape.net>
Tested-by: szegad <szegadlo@poczta.onet.pl>
Tested-by: prash <prash.n.rao@gmail.com>
Tested-by: amish <ammdispose-arch@yahoo.com>
Tested-by: Matthias <morpheusxyz123@yahoo.de>
Reviewed-by: Javi Merino <javi.merino@arm.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Chen Yu <yu.c.chen@intel.com>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>

diff --git a/drivers/thermal/step_wise.c b/drivers/thermal/step_wise.c
index 5a0f12d08e8b81cc26b71b7e6c065091a098920f..ec4ea5940bf761ee5c53dd1968a1ebb597144476 100644 (file)
--- a/drivers/thermal/step_wise.c
+++ b/drivers/thermal/step_wise.c
@@ -63,6 +63,19 @@ static unsigned long get_target_state(struct thermal_instance *instance,
        next_target = instance->target;
        dev_dbg(&cdev->device, "cur_state=%ld\n", cur_state);
 
+       if (!instance->initialized) {
+               if (throttle) {
+                       next_target = (cur_state + 1) >= instance->upper ?
+                                       instance->upper :
+                                       ((cur_state + 1) < instance->lower ?
+                                       instance->lower : (cur_state + 1));
+               } else {
+                       next_target = THERMAL_NO_TARGET;
+               }
+
+               return next_target;
+       }
+
        switch (trend) {
        case THERMAL_TREND_RAISING:
                if (throttle) {
@@ -149,7 +162,7 @@ static void thermal_zone_trip_update(struct thermal_zone_device *tz, int trip)
                dev_dbg(&instance->cdev->device, "old_target=%d, target=%d\n",
                                        old_target, (int)instance->target);
 
-               if (old_target == instance->target)
+               if (instance->initialized && old_target == instance->target)
                        continue;
 
                /* Activate a passive thermal instance */
@@ -161,7 +174,7 @@ static void thermal_zone_trip_update(struct thermal_zone_device *tz, int trip)
                        instance->target == THERMAL_NO_TARGET)
                        update_passive_instance(tz, trip_type, -1);
 
-
+               instance->initialized = true;
                instance->cdev->updated = false; /* cdev needs update */
        }
 

diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c
index 4108db7e10c1094622d4abca08017db3125cf80e..80e812378c0c11515aceb4546f2d62f6abd8cb80 100644 (file)
--- a/drivers/thermal/thermal_core.c
+++ b/drivers/thermal/thermal_core.c
@@ -471,8 +471,22 @@ static void update_temperature(struct thermal_zone_device *tz)
        mutex_unlock(&tz->lock);
 
        trace_thermal_temperature(tz);
-       dev_dbg(&tz->device, "last_temperature=%d, current_temperature=%d\n",
-                               tz->last_temperature, tz->temperature);
+       if (tz->last_temperature == THERMAL_TEMP_INVALID)
+               dev_dbg(&tz->device, "last_temperature N/A, current_temperature=%d\n",
+                       tz->temperature);
+       else
+               dev_dbg(&tz->device, "last_temperature=%d, current_temperature=%d\n",
+                       tz->last_temperature, tz->temperature);
+}
+
+static void thermal_zone_device_reset(struct thermal_zone_device *tz)
+{
+       struct thermal_instance *pos;
+
+       tz->temperature = THERMAL_TEMP_INVALID;
+       tz->passive = 0;
+       list_for_each_entry(pos, &tz->thermal_instances, tz_node)
+               pos->initialized = false;
 }
 
 void thermal_zone_device_update(struct thermal_zone_device *tz)
@@ -1576,6 +1590,7 @@ struct thermal_zone_device *thermal_zone_device_register(const char *type,
        if (!tz->ops->get_temp)
                thermal_zone_device_set_polling(tz, 0);
 
+       thermal_zone_device_reset(tz);
        thermal_zone_device_update(tz);
 
        return tz;

diff --git a/drivers/thermal/thermal_core.h b/drivers/thermal/thermal_core.h
index 8e391812e50377664f079cb83f61c380b16e6d93..dce86ee8e9d7156381c2144489b94f5e2824dbd0 100644 (file)
--- a/drivers/thermal/thermal_core.h
+++ b/drivers/thermal/thermal_core.h
@@ -41,6 +41,7 @@ struct thermal_instance {
        struct thermal_zone_device *tz;
        struct thermal_cooling_device *cdev;
        int trip;
+       bool initialized;
        unsigned long upper;    /* Highest cooling state for this trip point */
        unsigned long lower;    /* Lowest cooling state for this trip point */
        unsigned long target;   /* expected cooling state */

diff --git a/include/linux/thermal.h b/include/linux/thermal.h
index 5eac316490eab9ca0ad1a864be2b6fedb823f332..fb96b15693d4441ca1bbb4b598765d56b95a4b87 100644 (file)
--- a/include/linux/thermal.h
+++ b/include/linux/thermal.h
@@ -40,6 +40,9 @@
 /* No upper/lower limit requirement */
 #define THERMAL_NO_LIMIT       ((u32)~0)
 
+/* use value, which < 0K, to indicate an invalid/uninitialized temperature */
+#define THERMAL_TEMP_INVALID   -274000
+
 /* Unit conversion macros */
 #define KELVIN_TO_CELSIUS(t)   (long)(((long)t-2732 >= 0) ?    \
                                ((long)t-2732+5)/10 : ((long)t-2732-5)/10)