drivers/thermal/thermal_trip.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *  Copyright (C) 2008 Intel Corp
   4  *  Copyright (C) 2008 Zhang Rui <rui.zhang@intel.com>
   5  *  Copyright (C) 2008 Sujith Thomas <sujith.thomas@intel.com>
   6  *  Copyright 2022 Linaro Limited
   7  *
   8  * Thermal trips handling
   9  */
  10 #include "thermal_core.h"
  11
  12 static const char *trip_type_names[] = {
  13         [THERMAL_TRIP_ACTIVE] = "active",
  14         [THERMAL_TRIP_PASSIVE] = "passive",
  15         [THERMAL_TRIP_HOT] = "hot",
  16         [THERMAL_TRIP_CRITICAL] = "critical",
  17 };
  18
  19 const char *thermal_trip_type_name(enum thermal_trip_type trip_type)
  20 {
  21         if (trip_type < THERMAL_TRIP_ACTIVE || trip_type > THERMAL_TRIP_CRITICAL)
  22                 return "unknown";
  23
  24         return trip_type_names[trip_type];
  25 }
  26
  27 int for_each_thermal_trip(struct thermal_zone_device *tz,
  28                           int (*cb)(struct thermal_trip *, void *),
  29                           void *data)
  30 {
  31         struct thermal_trip_desc *td;
  32         int ret;
  33
  34         for_each_trip_desc(tz, td) {
  35                 ret = cb(&td->trip, data);
  36                 if (ret)
  37                         return ret;
  38         }
  39
  40         return 0;
  41 }
  42 EXPORT_SYMBOL_GPL(for_each_thermal_trip);
  43
  44 int thermal_zone_for_each_trip(struct thermal_zone_device *tz,
  45                                int (*cb)(struct thermal_trip *, void *),
  46                                void *data)
  47 {
  48         guard(thermal_zone)(tz);
  49
  50         return for_each_thermal_trip(tz, cb, data);
  51 }
  52 EXPORT_SYMBOL_GPL(thermal_zone_for_each_trip);
  53
  54 void thermal_zone_set_trips(struct thermal_zone_device *tz, int low, int high)
  55 {
  56         int ret;
  57
  58         lockdep_assert_held(&tz->lock);
  59
  60         if (!tz->ops.set_trips)
  61                 return;
  62
  63         /* No need to change trip points */
  64         if (tz->prev_low_trip == low && tz->prev_high_trip == high)
  65                 return;
  66
  67         tz->prev_low_trip = low;
  68         tz->prev_high_trip = high;
  69
  70         dev_dbg(&tz->device,
  71                 "new temperature boundaries: %d < x < %d\n", low, high);
  72
  73         /*
  74          * Set a temperature window. When this window is left the driver
  75          * must inform the thermal core via thermal_zone_device_update.
  76          */
  77         ret = tz->ops.set_trips(tz, low, high);
  78         if (ret)
  79                 dev_err(&tz->device, "Failed to set trips: %d\n", ret);
  80 }
  81
  82 int thermal_zone_trip_id(const struct thermal_zone_device *tz,
  83                          const struct thermal_trip *trip)
  84 {
  85         /*
  86          * Assume the trip to be located within the bounds of the thermal
  87          * zone's trips[] table.
  88          */
  89         return trip_to_trip_desc(trip) - tz->trips;
  90 }