IPXE/ipxe-3fe683e/src/core/device.c

   1 /*
   2  * Copyright (C) 2006 Michael Brown <mbrown@fensystems.co.uk>.
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public License as
   6  * published by the Free Software Foundation; either version 2 of the
   7  * License, or any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful, but
  10  * WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write to the Free Software
  16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  17  * 02110-1301, USA.
  18  *
  19  * You can also choose to distribute this program under the terms of
  20  * the Unmodified Binary Distribution Licence (as given in the file
  21  * COPYING.UBDL), provided that you have satisfied its requirements.
  22  */
  23
  24 FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
  25
  26 #include <string.h>
  27 #include <ipxe/list.h>
  28 #include <ipxe/tables.h>
  29 #include <ipxe/init.h>
  30 #include <ipxe/interface.h>
  31 #include <ipxe/device.h>
  32
  33 /**
  34  * @file
  35  *
  36  * Device model
  37  *
  38  */
  39
  40 /** Registered root devices */
  41 static LIST_HEAD ( devices );
  42
  43 /** Device removal inhibition counter */
  44 int device_keep_count = 0;
  45
  46 /**
  47  * Probe a root device
  48  *
  49  * @v rootdev           Root device
  50  * @ret rc              Return status code
  51  */
  52 static int rootdev_probe ( struct root_device *rootdev ) {
  53         int rc;
  54
  55         DBG ( "Adding %s root bus\n", rootdev->dev.name );
  56         if ( ( rc = rootdev->driver->probe ( rootdev ) ) != 0 ) {
  57                 DBG ( "Failed to add %s root bus: %s\n",
  58                       rootdev->dev.name, strerror ( rc ) );
  59                 return rc;
  60         }
  61
  62         return 0;
  63 }
  64
  65 /**
  66  * Remove a root device
  67  *
  68  * @v rootdev           Root device
  69  */
  70 static void rootdev_remove ( struct root_device *rootdev ) {
  71         rootdev->driver->remove ( rootdev );
  72         DBG ( "Removed %s root bus\n", rootdev->dev.name );
  73 }
  74
  75 /**
  76  * Probe all devices
  77  *
  78  * This initiates probing for all devices in the system.  After this
  79  * call, the device hierarchy will be populated, and all hardware
  80  * should be ready to use.
  81  */
  82 static void probe_devices ( void ) {
  83         struct root_device *rootdev;
  84         int rc;
  85
  86         for_each_table_entry ( rootdev, ROOT_DEVICES ) {
  87                 list_add ( &rootdev->dev.siblings, &devices );
  88                 INIT_LIST_HEAD ( &rootdev->dev.children );
  89                 if ( ( rc = rootdev_probe ( rootdev ) ) != 0 )
  90                         list_del ( &rootdev->dev.siblings );
  91         }
  92 }
  93
  94 /**
  95  * Remove all devices
  96  *
  97  */
  98 static void remove_devices ( int booting __unused ) {
  99         struct root_device *rootdev;
 100         struct root_device *tmp;
 101
 102         if ( device_keep_count != 0 ) {
 103                 DBG ( "Refusing to remove devices on shutdown\n" );
 104                 return;
 105         }
 106
 107         list_for_each_entry_safe ( rootdev, tmp, &devices, dev.siblings ) {
 108                 rootdev_remove ( rootdev );
 109                 list_del ( &rootdev->dev.siblings );
 110         }
 111 }
 112
 113 //struct startup_fn startup_devices __startup_fn ( STARTUP_NORMAL ) = {
 114 struct startup_fn startup_devices  = {
 115         .name = "devices",
 116         .startup = probe_devices,
 117         .shutdown = remove_devices,
 118 };
 119
 120 /**
 121  * Identify a device behind an interface
 122  *
 123  * @v intf              Interface
 124  * @ret device          Device, or NULL
 125  */
 126 struct device * identify_device ( struct interface *intf ) {
 127         struct interface *dest;
 128         identify_device_TYPE ( void * ) *op =
 129                 intf_get_dest_op ( intf, identify_device, &dest );
 130         void *object = intf_object ( dest );
 131         void *device;
 132
 133         if ( op ) {
 134                 device = op ( object );
 135         } else {
 136                 /* Default is to return NULL */
 137                 device = NULL;
 138         }
 139
 140         intf_put ( dest );
 141         return device;
 142 }