In the of-thermal driver, it register a thermal zone device
without governor, since the governers are not static, we
should be able to update to a new one in run-time, so I add
a new fucntion thermal_update_governor() to do it.
In the future, the governor will be more complex, it may want
to tune governor-specific parameters/configuration for
different thermal zone at different run-time, so I add
start/stop for the governor and add governor_data as governor's
parameters, so that the thermal platform driver can change
the governor with start/stop, and tune the governor parameters
in run-time.
Signed-off-by: Wei Ni <wni@xxxxxxxxxx>
---
Documentation/thermal/sysfs-api.txt | 5 +++
drivers/thermal/thermal_core.c | 80 +++++++++++++++++++++++++++++++----
include/linux/thermal.h | 12 ++++++
3 files changed, 88 insertions(+), 9 deletions(-)
diff --git a/Documentation/thermal/sysfs-api.txt b/Documentation/thermal/sysfs-api.txt
index 6a70b55c..7efd8e6 100644
--- a/Documentation/thermal/sysfs-api.txt
+++ b/Documentation/thermal/sysfs-api.txt
@@ -405,3 +405,8 @@ platform data is provided, this uses the step_wise throttling policy.
This function serves as an arbitrator to set the state of a cooling
device. It sets the cooling device to the deepest cooling state if
possible.
+
+5.5:thermal_update_governor:
+This function update the thermal zone's governor to a new one and update
+the governor data of the new governor for that thermal zone. Returns 0 if
+success, an erro code otherwise.
diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c
index aab1df8..d922baf 100644
--- a/drivers/thermal/thermal_core.c
+++ b/drivers/thermal/thermal_core.c
@@ -93,10 +93,17 @@ int thermal_register_governor(struct thermal_governor *governor)
name = pos->tzp->governor_name;
else
name = DEFAULT_THERMAL_GOVERNOR;
- if (!strnicmp(name, governor->name, THERMAL_NAME_LENGTH))
+ if (!strnicmp(name, governor->name, THERMAL_NAME_LENGTH)) {
+ if (governor->start) {
+ err = governor->start(pos);
+ if (err < 0)
+ goto exit;
+ }
pos->governor = governor;
+ }
}
+exit:
mutex_unlock(&thermal_list_lock);
mutex_unlock(&thermal_governor_lock);
@@ -119,8 +126,11 @@ void thermal_unregister_governor(struct thermal_governor *governor)
list_for_each_entry(pos, &thermal_tz_list, node) {
if (!strnicmp(pos->governor->name, governor->name,
- THERMAL_NAME_LENGTH))
+ THERMAL_NAME_LENGTH)) {
+ if (pos->governor->stop)
+ pos->governor->stop(pos);
pos->governor = NULL;
+ }
}
mutex_unlock(&thermal_list_lock);
@@ -130,6 +140,51 @@ exit:
return;
}
+/**
+ * thermal_update_governor() - update the thermal zone device's governor
+ * to a new one.
+ * @tzd: pointer of thermal zone device, which need to update governor.
+ * @name: new governor name.
+ * @gov_data: governor data for the new governor if needed.
+ *
+ * Return: On success returns 0, an error code otherwise
+ */
+int thermal_update_governor(struct thermal_zone_device *tzd,
+ const char *name, void *gov_data)
+{
+ struct thermal_governor *old_gov, *new_gov;
+ int ret = 0;
+
+ mutex_lock(&thermal_governor_lock);
+
+ new_gov = __find_governor(name);
+ if (!new_gov) {
+ ret = -EINVAL;
+ goto exit;
+ }
+
+ old_gov = tzd->governor;
+
+ if (old_gov && old_gov->stop)
+ old_gov->stop(tzd);
+
+ if (new_gov->start) {
+ ret = new_gov->start(tzd);
+ if (ret < 0) {
+ if (old_gov && old_gov->start)
+ old_gov->start(tzd);
+ goto exit;
+ }
+ }
+
+ tzd->governor = new_gov;
+ tzd->governor_data = gov_data;
+
+exit:
+ mutex_unlock(&thermal_governor_lock);
+ return ret;
+}
+
static int get_idr(struct idr *idr, struct mutex *lock, int *id)
{
int ret;
@@ -734,22 +789,17 @@ policy_store(struct device *dev, struct device_attribute *attr,
{
int ret = -EINVAL;
struct thermal_zone_device *tz = to_thermal_zone(dev);
- struct thermal_governor *gov;
char name[THERMAL_NAME_LENGTH];
snprintf(name, sizeof(name), "%s", buf);
- mutex_lock(&thermal_governor_lock);
-
- gov = __find_governor(strim(name));
- if (!gov)
+ ret = thermal_update_governor(tz, strim(name), NULL);
+ if (ret < 0)
goto exit;
- tz->governor = gov;
ret = count;
exit:
- mutex_unlock(&thermal_governor_lock);
return ret;
}
@@ -1559,6 +1609,12 @@ struct thermal_zone_device *thermal_zone_device_register(const char *type,
else
tz->governor = __find_governor(DEFAULT_THERMAL_GOVERNOR);
+ if (tz->governor->start) {
+ result = tz->governor->start(tz);
+ if (result < 0)
+ tz->governor = NULL;
+ }
+
mutex_unlock(&thermal_governor_lock);
if (!tz->tzp || !tz->tzp->no_hwmon) {
@@ -1585,6 +1641,9 @@ struct thermal_zone_device *thermal_zone_device_register(const char *type,
return tz;
unregister:
+ if (tz->governor && tz->governor->stop)
+ tz->governor->stop(tz);
+ tz->governor = NULL;
release_idr(&thermal_tz_idr, &thermal_idr_lock, tz->id);
device_unregister(&tz->device);
return ERR_PTR(result);
@@ -1648,6 +1707,9 @@ void thermal_zone_device_unregister(struct thermal_zone_device *tz)
device_remove_file(&tz->device, &dev_attr_policy);
device_remove_file(&tz->device, &dev_attr_available_policies);
remove_trip_attrs(tz);
+
+ if (tz->governor && tz->governor->stop)
+ tz->governor->stop(tz);
tz->governor = NULL;
thermal_remove_hwmon_sysfs(tz);
diff --git a/include/linux/thermal.h b/include/linux/thermal.h
index f7e11c7..a473736 100644
--- a/include/linux/thermal.h
+++ b/include/linux/thermal.h
@@ -177,6 +177,7 @@ struct thermal_zone_device {
struct thermal_zone_device_ops *ops;
const struct thermal_zone_params *tzp;
struct thermal_governor *governor;
+ void *governor_data;
struct list_head thermal_instances;
struct idr idr;
struct mutex lock; /* protect thermal_instances list */
@@ -187,6 +188,15 @@ struct thermal_zone_device {
/* Structure that holds thermal governor information */
struct thermal_governor {
char name[THERMAL_NAME_LENGTH];
+
+ /*
+ * The start and stop operations will be called when thermal zone is
+ * registered and when change governor via sysfs or driver in running
+ * time.
+ */
+ int (*start)(struct thermal_zone_device *tz);
+ void (*stop)(struct thermal_zone_device *tz);
+
int (*throttle)(struct thermal_zone_device *tz, int trip);
struct list_head governor_list;
};
@@ -293,6 +303,8 @@ struct thermal_instance *get_thermal_instance(struct thermal_zone_device *,
struct thermal_cooling_device *, int);
void thermal_cdev_update(struct thermal_cooling_device *);
void thermal_notify_framework(struct thermal_zone_device *, int);
+int thermal_update_governor(struct thermal_zone_device *, const char *,
+ void *);
#ifdef CONFIG_NET
extern int thermal_generate_netlink_event(struct thermal_zone_device *tz,
--
1.7.9.5
--
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