drivers/base/power/domain_governor.c

   1 /*
   2  * drivers/base/power/domain_governor.c - Governors for device PM domains.
   3  *
   4  * Copyright (C) 2011 Rafael J. Wysocki <rjw@sisk.pl>, Renesas Electronics Corp.
   5  *
   6  * This file is released under the GPLv2.
   7  */
   8
   9 #include <linux/init.h>
  10 #include <linux/kernel.h>
  11 #include <linux/pm_domain.h>
  12 #include <linux/pm_qos.h>
  13
  14 /**
  15  * default_stop_ok - Default PM domain governor routine for stopping devices.
  16  * @dev: Device to check.
  17  */
  18 bool default_stop_ok(struct device *dev)
  19 {
  20         struct gpd_timing_data *td = &dev_gpd_data(dev)->td;
  21
  22         dev_dbg(dev, "%s()\n", __func__);
  23
  24         if (dev->power.max_time_suspended_ns < 0 || td->break_even_ns == 0)
  25                 return true;
  26
  27         return td->stop_latency_ns + td->start_latency_ns < td->break_even_ns
  28                 && td->break_even_ns < dev->power.max_time_suspended_ns;
  29 }
  30
  31 struct dev_power_governor simple_qos_governor = {
  32         .stop_ok = default_stop_ok,
  33 };