diff options
Diffstat (limited to 'Documentation/thermal/sysfs-api.txt')
| -rw-r--r-- | Documentation/thermal/sysfs-api.txt | 58 |
1 files changed, 44 insertions, 14 deletions
diff --git a/Documentation/thermal/sysfs-api.txt b/Documentation/thermal/sysfs-api.txt index 88c02334e35..87519cb379e 100644 --- a/Documentation/thermal/sysfs-api.txt +++ b/Documentation/thermal/sysfs-api.txt @@ -31,15 +31,17 @@ temperature) and throttle appropriate devices. 1. thermal sysfs driver interface functions 1.1 thermal zone device interface -1.1.1 struct thermal_zone_device *thermal_zone_device_register(char *name, +1.1.1 struct thermal_zone_device *thermal_zone_device_register(char *type, int trips, int mask, void *devdata, - struct thermal_zone_device_ops *ops) + struct thermal_zone_device_ops *ops, + const struct thermal_zone_params *tzp, + int passive_delay, int polling_delay)) This interface function adds a new thermal zone device (sensor) to /sys/class/thermal folder as thermal_zone[0-*]. It tries to bind all the thermal cooling devices registered at the same time. - name: the thermal zone name. + type: the thermal zone type. trips: the total number of trip points this thermal zone supports. mask: Bit string: If 'n'th bit is set, then trip point 'n' is writeable. devdata: device private data @@ -55,6 +57,14 @@ temperature) and throttle appropriate devices. .get_trip_type: get the type of certain trip point. .get_trip_temp: get the temperature above which the certain trip point will be fired. + .set_emul_temp: set the emulation temperature which helps in debugging + different threshold temperature points. + tzp: thermal zone platform parameters. + passive_delay: number of milliseconds to wait between polls when + performing passive cooling. + polling_delay: number of milliseconds to wait between polls when checking + whether trip points have been crossed (0 for interrupt driven systems). + 1.1.2 void thermal_zone_device_unregister(struct thermal_zone_device *tz) @@ -124,6 +134,13 @@ temperature) and throttle appropriate devices. this thermal zone and cdev, for a particular trip point. If nth bit is set, then the cdev and thermal zone are bound for trip point n. + .limits: This is an array of cooling state limits. Must have exactly + 2 * thermal_zone.number_of_trip_points. It is an array consisting + of tuples <lower-state upper-state> of state limits. Each trip + will be associated with one state limit tuple when binding. + A NULL pointer means <THERMAL_NO_LIMITS THERMAL_NO_LIMITS> + on all trips. These limits are used when binding a cdev to a + trip point. .match: This call back returns success(0) if the 'tz and cdev' need to be bound, as per platform data. 1.4.2 struct thermal_zone_params @@ -132,6 +149,11 @@ temperature) and throttle appropriate devices. This is an optional feature where some platforms can choose not to provide this data. .governor_name: Name of the thermal governor used for this zone + .no_hwmon: a boolean to indicate if the thermal to hwmon sysfs interface + is required. when no_hwmon == false, a hwmon sysfs interface + will be created. when no_hwmon == true, nothing will be done. + In case the thermal_zone_params is NULL, the hwmon interface + will be created (for backward compatibility). .num_tbps: Number of thermal_bind_params entries for this zone .tbp: thermal_bind_params entries @@ -153,6 +175,7 @@ Thermal zone device sys I/F, created once it's registered: |---trip_point_[0-*]_temp: Trip point temperature |---trip_point_[0-*]_type: Trip point type |---trip_point_[0-*]_hyst: Hysteresis value for this trip point + |---emul_temp: Emulated temperature set node Thermal cooling device sys I/F, created once it's registered: /sys/class/thermal/cooling_device[0-*]: @@ -252,6 +275,20 @@ passive Valid values: 0 (disabled) or greater than 1000 RW, Optional +emul_temp + Interface to set the emulated temperature method in thermal zone + (sensor). After setting this temperature, the thermal zone may pass + this temperature to platform emulation function if registered or + cache it locally. This is useful in debugging different temperature + threshold and its associated cooling action. This is write only node + and writing 0 on this node should disable emulation. + Unit: millidegree Celsius + WO, Optional + + WARNING: Be careful while enabling this option on production systems, + because userland can easily disable the thermal policy by simply + flooding this sysfs node with low temperature values. + ***************************** * Cooling device attributes * ***************************** @@ -329,8 +366,9 @@ The framework includes a simple notification mechanism, in the form of a netlink event. Netlink socket initialization is done during the _init_ of the framework. Drivers which intend to use the notification mechanism just need to call thermal_generate_netlink_event() with two arguments viz -(originator, event). Typically the originator will be an integer assigned -to a thermal_zone_device when it registers itself with the framework. The +(originator, event). The originator is a pointer to struct thermal_zone_device +from where the event has been originated. An integer which represents the +thermal zone device will be used in the message to identify the zone. The event will be one of:{THERMAL_AUX0, THERMAL_AUX1, THERMAL_CRITICAL, THERMAL_DEV_FAULT}. Notification can be sent when the current temperature crosses any of the configured thresholds. @@ -349,7 +387,7 @@ This function returns the thermal_instance corresponding to a given {thermal_zone, cooling_device, trip_point} combination. Returns NULL if such an instance does not exist. -5.3:notify_thermal_framework: +5.3:thermal_notify_framework: This function handles the trip events from sensor drivers. It starts throttling the cooling devices according to the policy configured. For CRITICAL and HOT trip points, this notifies the respective drivers, @@ -361,11 +399,3 @@ 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_register_governor: -This function lets the various thermal governors to register themselves -with the Thermal framework. At run time, depending on a zone's platform -data, a particular governor is used for throttling. - -5.6:thermal_unregister_governor: -This function unregisters a governor from the thermal framework. |