drivers/thermal/gov_user_space.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  *  user_space.c - A simple user space Thermal events notifier
   4  *
   5  *  Copyright (C) 2012 Intel Corp
   6  *  Copyright (C) 2012 Durgadoss R <durgadoss.r@intel.com>
   7  *
   8  *  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   9  *
  10  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  11  */
  12
  13 #include <linux/slab.h>
  14 #include <linux/thermal.h>
  15
  16 #include "thermal_core.h"
  17
  18 static int user_space_bind(struct thermal_zone_device *tz)
  19 {
  20         pr_info_once("Consider using thermal netlink events interface\n");
  21
  22         return 0;
  23 }
  24
  25 /**
  26  * user_space_trip_crossed - Notify user space about trip crossing events
  27  * @tz: thermal_zone_device
  28  * @trip: trip point
  29  * @upward: whether or not the trip has been crossed on the way up
  30  *
  31  * This function notifies the user space through UEvents.
  32  */
  33 static void user_space_trip_crossed(struct thermal_zone_device *tz,
  34                                     const struct thermal_trip *trip,
  35                                     bool upward)
  36 {
  37         char *thermal_prop[5];
  38         int i;
  39
  40         lockdep_assert_held(&tz->lock);
  41
  42         thermal_prop[0] = kasprintf(GFP_KERNEL, "NAME=%s", tz->type);
  43         thermal_prop[1] = kasprintf(GFP_KERNEL, "TEMP=%d", tz->temperature);
  44         thermal_prop[2] = kasprintf(GFP_KERNEL, "TRIP=%d",
  45                                     thermal_zone_trip_id(tz, trip));
  46         thermal_prop[3] = kasprintf(GFP_KERNEL, "EVENT=%d", tz->notify_event);
  47         thermal_prop[4] = NULL;
  48         kobject_uevent_env(&tz->device.kobj, KOBJ_CHANGE, thermal_prop);
  49         for (i = 0; i < 4; ++i)
  50                 kfree(thermal_prop[i]);
  51 }
  52
  53 static struct thermal_governor thermal_gov_user_space = {
  54         .name           = "user_space",
  55         .trip_crossed   = user_space_trip_crossed,
  56         .bind_to_tz     = user_space_bind,
  57 };
  58 THERMAL_GOVERNOR_DECLARE(thermal_gov_user_space);