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 /**
  23  * We handle system devices differently - we suspend and shut them
  24  * down last and resume them first. That way, we don't do anything stupid like
  25  * shutting down the interrupt controller before any devices..
  26  *
  27  * Note that there are not different stages for power management calls -
  28  * they only get one called once when interrupts are disabled.
  29  */
  30
  31 extern int sysdev_shutdown(void);
  32
  33 /**
  34  * device_shutdown - call ->shutdown() on each device to shutdown.
  35  */
  36 void device_shutdown(void)
  37 {
  38         struct device * dev;
  39
  40         down_write(&devices_subsys.rwsem);
  41         list_for_each_entry_reverse(dev, &devices_subsys.kset.list,
  42                                 kobj.entry) {
  43                 if (dev->bus && dev->bus->shutdown) {
  44                         dev_dbg(dev, "shutdown\n");
  45                         dev->bus->shutdown(dev);
  46                 } else if (dev->driver && dev->driver->shutdown) {
  47                         dev_dbg(dev, "shutdown\n");
  48                         dev->driver->shutdown(dev);
  49                 }
  50         }
  51         up_write(&devices_subsys.rwsem);
  52
  53         sysdev_shutdown();
  54 }
  55