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  *  You should have received a copy of the GNU General Public License along
  24  *  with this program; if not, write to the Free Software Foundation, Inc.,
  25  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
  26  *
  27  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  28  */
  29 #include <linux/acpi.h>
  30 #include <linux/container.h>
  31
  32 #include "internal.h"
  33
  34 #define PREFIX "ACPI: "
  35
  36 #define _COMPONENT                      ACPI_CONTAINER_COMPONENT
  37 ACPI_MODULE_NAME("container");
  38
  39 static const struct acpi_device_id container_device_ids[] = {
  40         {"ACPI0004", 0},
  41         {"PNP0A05", 0},
  42         {"PNP0A06", 0},
  43         {"", 0},
  44 };
  45
  46 static int acpi_container_offline(struct container_dev *cdev)
  47 {
  48         struct acpi_device *adev = ACPI_COMPANION(&cdev->dev);
  49         struct acpi_device *child;
  50
  51         /* Check all of the dependent devices' physical companions. */
  52         list_for_each_entry(child, &adev->children, node)
  53                 if (!acpi_scan_is_offline(child, false))
  54                         return -EBUSY;
  55
  56         return 0;
  57 }
  58
  59 static void acpi_container_release(struct device *dev)
  60 {
  61         kfree(to_container_dev(dev));
  62 }
  63
  64 static int container_device_attach(struct acpi_device *adev,
  65                                    const struct acpi_device_id *not_used)
  66 {
  67         struct container_dev *cdev;
  68         struct device *dev;
  69         int ret;
  70
  71         cdev = kzalloc(sizeof(*cdev), GFP_KERNEL);
  72         if (!cdev)
  73                 return -ENOMEM;
  74
  75         cdev->offline = acpi_container_offline;
  76         dev = &cdev->dev;
  77         dev->bus = &container_subsys;
  78         dev_set_name(dev, "%s", dev_name(&adev->dev));
  79         ACPI_COMPANION_SET(dev, adev);
  80         dev->release = acpi_container_release;
  81         ret = device_register(dev);
  82         if (ret)
  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 struct acpi_scan_handler container_handler = {
  99         .ids = container_device_ids,
 100         .attach = container_device_attach,
 101         .detach = container_device_detach,
 102         .hotplug = {
 103                 .enabled = true,
 104                 .demand_offline = true,
 105         },
 106 };
 107
 108 void __init acpi_container_init(void)
 109 {
 110         acpi_scan_add_handler_with_hotplug(&container_handler, "container");
 111 }