drivers/acpi/container.c

   1 /*
   2  * container.c  - ACPI Generic Container Driver
   3  *
   4  * Copyright (C) 2004 Anil S Keshavamurthy (anil.s.keshavamurthy@intel.com)
   5  * Copyright (C) 2004 Keiichiro Tokunaga (tokunaga.keiich@jp.fujitsu.com)
   6  * Copyright (C) 2004 Motoyuki Ito (motoyuki@soft.fujitsu.com)
   7  * Copyright (C) 2004 FUJITSU LIMITED
   8  * Copyright (C) 2004, 2013 Intel Corp.
   9  * Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
  10  *
  11  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  12  *
  13  *  This program is free software; you can redistribute it and/or modify
  14  *  it under the terms of the GNU General Public License as published by
  15  *  the Free Software Foundation; either version 2 of the License, or (at
  16  *  your option) any later version.
  17  *
  18  *  This program is distributed in the hope that it will be useful, but
  19  *  WITHOUT ANY WARRANTY; without even the implied warranty of
  20  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  21  *  General Public License for more details.
  22  *
  23  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  24  */
  25 #include <linux/acpi.h>
  26 #include <linux/container.h>
  27
  28 #include "internal.h"
  29
  30 #define _COMPONENT                      ACPI_CONTAINER_COMPONENT
  31 ACPI_MODULE_NAME("container");
  32
  33 static const struct acpi_device_id container_device_ids[] = {
  34         {"ACPI0004", 0},
  35         {"PNP0A05", 0},
  36         {"PNP0A06", 0},
  37         {"", 0},
  38 };
  39
  40 #ifdef CONFIG_ACPI_CONTAINER
  41
  42 static int acpi_container_offline(struct container_dev *cdev)
  43 {
  44         struct acpi_device *adev = ACPI_COMPANION(&cdev->dev);
  45         struct acpi_device *child;
  46
  47         /* Check all of the dependent devices' physical companions. */
  48         list_for_each_entry(child, &adev->children, node)
  49                 if (!acpi_scan_is_offline(child, false))
  50                         return -EBUSY;
  51
  52         return 0;
  53 }
  54
  55 static void acpi_container_release(struct device *dev)
  56 {
  57         kfree(to_container_dev(dev));
  58 }
  59
  60 static int container_device_attach(struct acpi_device *adev,
  61                                    const struct acpi_device_id *not_used)
  62 {
  63         struct container_dev *cdev;
  64         struct device *dev;
  65         int ret;
  66
  67         if (adev->flags.is_dock_station)
  68                 return 0;
  69
  70         cdev = kzalloc(sizeof(*cdev), GFP_KERNEL);
  71         if (!cdev)
  72                 return -ENOMEM;
  73
  74         cdev->offline = acpi_container_offline;
  75         dev = &cdev->dev;
  76         dev->bus = &container_subsys;
  77         dev_set_name(dev, "%s", dev_name(&adev->dev));
  78         ACPI_COMPANION_SET(dev, adev);
  79         dev->release = acpi_container_release;
  80         ret = device_register(dev);
  81         if (ret) {
  82                 put_device(dev);
  83                 return ret;
  84         }
  85         adev->driver_data = dev;
  86         return 1;
  87 }
  88
  89 static void container_device_detach(struct acpi_device *adev)
  90 {
  91         struct device *dev = acpi_driver_data(adev);
  92
  93         adev->driver_data = NULL;
  94         if (dev)
  95                 device_unregister(dev);
  96 }
  97
  98 static void container_device_online(struct acpi_device *adev)
  99 {
 100         struct device *dev = acpi_driver_data(adev);
 101
 102         kobject_uevent(&dev->kobj, KOBJ_ONLINE);
 103 }
 104
 105 static struct acpi_scan_handler container_handler = {
 106         .ids = container_device_ids,
 107         .attach = container_device_attach,
 108         .detach = container_device_detach,
 109         .hotplug = {
 110                 .enabled = true,
 111                 .demand_offline = true,
 112                 .notify_online = container_device_online,
 113         },
 114 };
 115
 116 void __init acpi_container_init(void)
 117 {
 118         acpi_scan_add_handler(&container_handler);
 119 }
 120
 121 #else
 122
 123 static struct acpi_scan_handler container_handler = {
 124         .ids = container_device_ids,
 125 };
 126
 127 void __init acpi_container_init(void)
 128 {
 129         acpi_scan_add_handler_with_hotplug(&container_handler, "container");
 130 }
 131
 132 #endif /* CONFIG_ACPI_CONTAINER */