drivers/base/power/shutdown.c

   1 /*
   2  * shutdown.c - power management functions for the device tree.
   3  *
   4  * Copyright (c) 2002-3 Patrick Mochel
   5  *               2002-3 Open Source Development Lab
   6  *
   7  * This file is released under the GPLv2
   8  *
   9  */
  10
  11 #include <linux/config.h>
  12 #include <linux/device.h>
  13 #include <asm/semaphore.h>
  14
  15 #include "power.h"
  16
  17 #define to_dev(node) container_of(node, struct device, kobj.entry)
  18
  19 extern struct subsystem devices_subsys;
  20
  21
  22 int device_detach_shutdown(struct device * dev)
  23 {
  24         if (!dev->detach_state)
  25                 return 0;
  26
  27         if (dev->detach_state == DEVICE_PM_OFF) {
  28                 if (dev->driver && dev->driver->shutdown) {
  29                         dev_dbg(dev, "shutdown\n");
  30                         dev->driver->shutdown(dev);
  31                 }
  32                 return 0;
  33         }
  34         return dpm_runtime_suspend(dev, dev->detach_state);
  35 }
  36
  37
  38 /**
  39  * We handle system devices differently - we suspend and shut them
  40  * down last and resume them first. That way, we don't do anything stupid like
  41  * shutting down the interrupt controller before any devices..
  42  *
  43  * Note that there are not different stages for power management calls -
  44  * they only get one called once when interrupts are disabled.
  45  */
  46
  47 extern int sysdev_shutdown(void);
  48
  49 /**
  50  * device_shutdown - call ->shutdown() on each device to shutdown.
  51  */
  52 void device_shutdown(void)
  53 {
  54         struct device * dev;
  55
  56         down_write(&devices_subsys.rwsem);
  57         list_for_each_entry_reverse(dev, &devices_subsys.kset.list,
  58                                 kobj.entry) {
  59                 if (dev->driver && dev->driver->shutdown) {
  60                         dev_dbg(dev, "shutdown\n");
  61                         dev->driver->shutdown(dev);
  62                 }
  63         }
  64         up_write(&devices_subsys.rwsem);
  65
  66         sysdev_shutdown();
  67 }
  68