cvs.zerfleddert.de Git - ms2-kexec/blob - driver_sys.c

   1 /*
   2  * sys.c - pseudo-bus for system 'devices' (cpus, PICs, timers, etc)
   3  *
   4  * Copyright (c) 2002-3 Patrick Mochel
   5  *               2002-3 Open Source Development Lab
   6  * This Edition is maintained by Matthew Veety (aliasxerog) <mveety@gmail.com>
   7  *
   8  * This file is released under the GPLv2
   9  *
  10  * This exports a 'system' bus type.
  11  * By default, a 'sys' bus gets added to the root of the system. There will
  12  * always be core system devices. Devices can use sysdev_register() to
  13  * add themselves as children of the system bus.
  14  */
  15
  16 #include <linux/sysdev.h>
  17 #include <linux/err.h>
  18 #include <linux/module.h>
  19 #include <linux/kernel.h>
  20 #include <linux/init.h>
  21 #include <linux/slab.h>
  22 #include <linux/string.h>
  23 #include <linux/pm.h>
  24 #include <linux/device.h>
  25 #include <linux/mutex.h>
  26 #include <linux/smp_lock.h>
  27
  28
  29 #define to_sysdev(k) container_of(k, struct sys_device, kobj)
  30 #define to_sysdev_attr(a) container_of(a, struct sysdev_attribute, attr)
  31
  32 static struct sysdev_class dummy_sysclass = {
  33          .name="dummy",
  34 };
  35
  36
  37 /**
  38  *      sysdev_shutdown - Shut down all system devices.
  39  *
  40  *      Loop over each class of system devices, and the devices in each
  41  *      of those classes. For each device, we call the shutdown method for
  42  *      each driver registered for the device - the auxillaries,
  43  *      and the class driver.
  44  *
  45  *      Note: The list is iterated in reverse order, so that we shut down
  46  *      child devices before we shut down thier parents. The list ordering
  47  *      is guaranteed by virtue of the fact that child devices are registered
  48  *      after their parents.
  49  */
  50 void sysdev_shutdown(void)
  51 {
  52         struct sysdev_class * cls;
  53         struct kset *system_kset;
  54
  55         pr_debug("Shutting Down System Devices\n");
  56
  57         lock_kernel();
  58
  59         sysdev_class_register(&dummy_sysclass);
  60         cls=&dummy_sysclass;
  61         system_kset=cls->kset.kobj.kset;
  62         sysdev_class_unregister(&dummy_sysclass);
  63
  64         list_for_each_entry_reverse(cls, &system_kset->list, kset.kobj.entry) {
  65                 struct sys_device * sysdev;
  66
  67                 pr_debug("Shutting down type '%s':\n",
  68                          kobject_name(&cls->kset.kobj));
  69
  70                 list_for_each_entry(sysdev, &cls->kset.list, kobj.entry) {
  71                         struct sysdev_driver * drv;
  72                         pr_debug(" %s\n", kobject_name(&sysdev->kobj));
  73
  74                         /* Call auxillary drivers first */
  75                         list_for_each_entry(drv, &cls->drivers, entry) {
  76                                 if (drv->shutdown)
  77                                         drv->shutdown(sysdev);
  78                         }
  79
  80                         /* Now call the generic one */
  81                         if (cls->shutdown)
  82                                 cls->shutdown(sysdev);
  83                 }
  84         }
  85         unlock_kernel();
  86 }