drivers/pnp/pnpbios/core.c

   1 /*
   2  * pnpbios -- PnP BIOS driver
   3  *
   4  * This driver provides access to Plug-'n'-Play services provided by
   5  * the PnP BIOS firmware, described in the following documents:
   6  *   Plug and Play BIOS Specification, Version 1.0A, 5 May 1994
   7  *   Plug and Play BIOS Clarification Paper, 6 October 1994
   8  *     Compaq Computer Corporation, Phoenix Technologies Ltd., Intel Corp.
   9  *
  10  * Originally (C) 1998 Christian Schmidt <schmidt@digadd.de>
  11  * Modifications (C) 1998 Tom Lees <tom@lpsg.demon.co.uk>
  12  * Minor reorganizations by David Hinds <dahinds@users.sourceforge.net>
  13  * Further modifications (C) 2001, 2002 by:
  14  *   Alan Cox <alan@redhat.com>
  15  *   Thomas Hood <jdthood@mail.com>
  16  *   Brian Gerst <bgerst@didntduck.org>
  17  *
  18  * Ported to the PnP Layer and several additional improvements (C) 2002
  19  * by Adam Belay <ambx1@neo.rr.com>
  20  *
  21  * This program is free software; you can redistribute it and/or modify it
  22  * under the terms of the GNU General Public License as published by the
  23  * Free Software Foundation; either version 2, or (at your option) any
  24  * later version.
  25  *
  26  * This program is distributed in the hope that it will be useful, but
  27  * WITHOUT ANY WARRANTY; without even the implied warranty of
  28  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  29  * General Public License for more details.
  30  *
  31  * You should have received a copy of the GNU General Public License
  32  * along with this program; if not, write to the Free Software
  33  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  34  */
  35
  36 /* Change Log
  37  *
  38  * Adam Belay - <ambx1@neo.rr.com> - March 16, 2003
  39  * rev 1.01     Only call pnp_bios_dev_node_info once
  40  *              Added pnpbios_print_status
  41  *              Added several new error messages and info messages
  42  *              Added pnpbios_interface_attach_device
  43  *              integrated core and proc init system
  44  *              Introduced PNPMODE flags
  45  *              Removed some useless includes
  46  */
  47
  48 #include <linux/types.h>
  49 #include <linux/module.h>
  50 #include <linux/init.h>
  51 #include <linux/linkage.h>
  52 #include <linux/kernel.h>
  53 #include <linux/pnpbios.h>
  54 #include <linux/device.h>
  55 #include <linux/pnp.h>
  56 #include <linux/mm.h>
  57 #include <linux/smp.h>
  58 #include <linux/slab.h>
  59 #include <linux/kmod.h>
  60 #include <linux/completion.h>
  61 #include <linux/spinlock.h>
  62
  63 #include <asm/page.h>
  64 #include <asm/desc.h>
  65 #include <asm/system.h>
  66 #include <asm/byteorder.h>
  67
  68 #include "pnpbios.h"
  69
  70
  71 /*
  72  *
  73  * PnP BIOS INTERFACE
  74  *
  75  */
  76
  77 static union pnp_bios_install_struct * pnp_bios_install = NULL;
  78
  79 int pnp_bios_present(void)
  80 {
  81         return (pnp_bios_install != NULL);
  82 }
  83
  84 struct pnp_dev_node_info node_info;
  85
  86 void *pnpbios_kmalloc(size_t size, int f)
  87 {
  88         void *p = kmalloc( size, f );
  89         if ( p == NULL )
  90                 printk(KERN_ERR "PnPBIOS: kmalloc() failed\n");
  91         else
  92                 memset(p, 0, size);
  93         return p;
  94 }
  95
  96 /*
  97  *
  98  * DOCKING FUNCTIONS
  99  *
 100  */
 101
 102 #ifdef CONFIG_HOTPLUG
 103
 104 static int unloading = 0;
 105 static struct completion unload_sem;
 106
 107 /*
 108  * (Much of this belongs in a shared routine somewhere)
 109  */
 110
 111 static int pnp_dock_event(int dock, struct pnp_docking_station_info *info)
 112 {
 113         char *argv [3], **envp, *buf, *scratch;
 114         int i = 0, value;
 115
 116         if (!hotplug_path [0])
 117                 return -ENOENT;
 118         if (!current->fs->root) {
 119                 return -EAGAIN;
 120         }
 121         if (!(envp = (char **) pnpbios_kmalloc (20 * sizeof (char *), GFP_KERNEL))) {
 122                 return -ENOMEM;
 123         }
 124         if (!(buf = pnpbios_kmalloc (256, GFP_KERNEL))) {
 125                 kfree (envp);
 126                 return -ENOMEM;
 127         }
 128
 129         /* only one standardized param to hotplug command: type */
 130         argv [0] = hotplug_path;
 131         argv [1] = "dock";
 132         argv [2] = 0;
 133
 134         /* minimal command environment */
 135         envp [i++] = "HOME=/";
 136         envp [i++] = "PATH=/sbin:/bin:/usr/sbin:/usr/bin";
 137
 138 #ifdef  DEBUG
 139         /* hint that policy agent should enter no-stdout debug mode */
 140         envp [i++] = "DEBUG=kernel";
 141 #endif
 142         /* extensible set of named bus-specific parameters,
 143          * supporting multiple driver selection algorithms.
 144          */
 145         scratch = buf;
 146
 147         /* action:  add, remove */
 148         envp [i++] = scratch;
 149         scratch += sprintf (scratch, "ACTION=%s", dock?"add":"remove") + 1;
 150
 151         /* Report the ident for the dock */
 152         envp [i++] = scratch;
 153         scratch += sprintf (scratch, "DOCK=%x/%x/%x",
 154                 info->location_id, info->serial, info->capabilities);
 155         envp[i] = 0;
 156
 157         value = call_usermodehelper (argv [0], argv, envp, 0);
 158         kfree (buf);
 159         kfree (envp);
 160         return 0;
 161 }
 162
 163 /*
 164  * Poll the PnP docking at regular intervals
 165  */
 166 static int pnp_dock_thread(void * unused)
 167 {
 168         static struct pnp_docking_station_info now;
 169         int docked = -1, d = 0;
 170         daemonize("kpnpbiosd");
 171         allow_signal(SIGKILL);
 172         while(!unloading && !signal_pending(current))
 173         {
 174                 int status;
 175
 176                 /*
 177                  * Poll every 2 seconds
 178                  */
 179                 set_current_state(TASK_INTERRUPTIBLE);
 180                 schedule_timeout(HZ*2);
 181                 if(signal_pending(current))
 182                         break;
 183
 184                 status = pnp_bios_dock_station_info(&now);
 185
 186                 switch(status)
 187                 {
 188                         /*
 189                          * No dock to manage
 190                          */
 191                         case PNP_FUNCTION_NOT_SUPPORTED:
 192                                 complete_and_exit(&unload_sem, 0);
 193                         case PNP_SYSTEM_NOT_DOCKED:
 194                                 d = 0;
 195                                 break;
 196                         case PNP_SUCCESS:
 197                                 d = 1;
 198                                 break;
 199                         default:
 200                                 pnpbios_print_status( "pnp_dock_thread", status );
 201                                 continue;
 202                 }
 203                 if(d != docked)
 204                 {
 205                         if(pnp_dock_event(d, &now)==0)
 206                         {
 207                                 docked = d;
 208 #if 0
 209                                 printk(KERN_INFO "PnPBIOS: Docking station %stached\n", docked?"at":"de");
 210 #endif
 211                         }
 212                 }
 213         }
 214         complete_and_exit(&unload_sem, 0);
 215 }
 216
 217 #endif   /* CONFIG_HOTPLUG */
 218
 219 static int pnpbios_get_resources(struct pnp_dev * dev, struct pnp_resource_table * res)
 220 {
 221         u8 nodenum = dev->number;
 222         struct pnp_bios_node * node;
 223
 224         /* just in case */
 225         if(!pnpbios_is_dynamic(dev))
 226                 return -EPERM;
 227
 228         node = pnpbios_kmalloc(node_info.max_node_size, GFP_KERNEL);
 229         if (!node)
 230                 return -1;
 231         if (pnp_bios_get_dev_node(&nodenum, (char )PNPMODE_DYNAMIC, node)) {
 232                 kfree(node);
 233                 return -ENODEV;
 234         }
 235         pnpbios_read_resources_from_node(res, node);
 236         dev->active = pnp_is_active(dev);
 237         kfree(node);
 238         return 0;
 239 }
 240
 241 static int pnpbios_set_resources(struct pnp_dev * dev, struct pnp_resource_table * res)
 242 {
 243         u8 nodenum = dev->number;
 244         struct pnp_bios_node * node;
 245         int ret;
 246
 247         /* just in case */
 248         if (!pnpbios_is_dynamic(dev))
 249                 return -EPERM;
 250
 251         node = pnpbios_kmalloc(node_info.max_node_size, GFP_KERNEL);
 252         if (!node)
 253                 return -1;
 254         if (pnp_bios_get_dev_node(&nodenum, (char )PNPMODE_DYNAMIC, node))
 255                 return -ENODEV;
 256         if(pnpbios_write_resources_to_node(res, node)<0) {
 257                 kfree(node);
 258                 return -1;
 259         }
 260         ret = pnp_bios_set_dev_node(node->handle, (char)PNPMODE_DYNAMIC, node);
 261         kfree(node);
 262         if (ret > 0)
 263                 ret = -1;
 264         return ret;
 265 }
 266
 267 static void pnpbios_zero_data_stream(struct pnp_bios_node * node)
 268 {
 269         unsigned char * p = (char *)node->data;
 270         unsigned char * end = (char *)(node->data + node->size);
 271         unsigned int len;
 272         int i;
 273         while ((char *)p < (char *)end) {
 274                 if(p[0] & 0x80) { /* large tag */
 275                         len = (p[2] << 8) | p[1];
 276                         p += 3;
 277                 } else {
 278                         if (((p[0]>>3) & 0x0f) == 0x0f)
 279                                 return;
 280                         len = p[0] & 0x07;
 281                         p += 1;
 282                 }
 283                 for (i = 0; i < len; i++)
 284                         p[i] = 0;
 285                 p += len;
 286         }
 287         printk(KERN_ERR "PnPBIOS: Resource structure did not contain an end tag.\n");
 288 }
 289
 290 static int pnpbios_disable_resources(struct pnp_dev *dev)
 291 {
 292         struct pnp_bios_node * node;
 293         u8 nodenum = dev->number;
 294         int ret;
 295
 296         /* just in case */
 297         if(dev->flags & PNPBIOS_NO_DISABLE || !pnpbios_is_dynamic(dev))
 298                 return -EPERM;
 299
 300         node = pnpbios_kmalloc(node_info.max_node_size, GFP_KERNEL);
 301         if (!node)
 302                 return -ENOMEM;
 303
 304         if (pnp_bios_get_dev_node(&nodenum, (char )PNPMODE_DYNAMIC, node)) {
 305                 kfree(node);
 306                 return -ENODEV;
 307         }
 308         pnpbios_zero_data_stream(node);
 309
 310         ret = pnp_bios_set_dev_node(dev->number, (char)PNPMODE_DYNAMIC, node);
 311         kfree(node);
 312         if (ret > 0)
 313                 ret = -1;
 314         return ret;
 315 }
 316
 317 /* PnP Layer support */
 318
 319 struct pnp_protocol pnpbios_protocol = {
 320         .name   = "Plug and Play BIOS",
 321         .get    = pnpbios_get_resources,
 322         .set    = pnpbios_set_resources,
 323         .disable = pnpbios_disable_resources,
 324 };
 325
 326 static int insert_device(struct pnp_dev *dev, struct pnp_bios_node * node)
 327 {
 328         struct list_head * pos;
 329         struct pnp_dev * pnp_dev;
 330         struct pnp_id *dev_id;
 331         char id[8];
 332
 333         /* check if the device is already added */
 334         dev->number = node->handle;
 335         list_for_each (pos, &pnpbios_protocol.devices){
 336                 pnp_dev = list_entry(pos, struct pnp_dev, protocol_list);
 337                 if (dev->number == pnp_dev->number)
 338                         return -1;
 339         }
 340
 341         /* set the initial values for the PnP device */
 342         dev_id = pnpbios_kmalloc(sizeof(struct pnp_id), GFP_KERNEL);
 343         if (!dev_id)
 344                 return -1;
 345         pnpid32_to_pnpid(node->eisa_id,id);
 346         memcpy(dev_id->id,id,7);
 347         pnp_add_id(dev_id, dev);
 348         pnpbios_parse_data_stream(dev, node);
 349         dev->active = pnp_is_active(dev);
 350         dev->flags = node->flags;
 351         if (!(dev->flags & PNPBIOS_NO_CONFIG))
 352                 dev->capabilities |= PNP_CONFIGURABLE;
 353         if (!(dev->flags & PNPBIOS_NO_DISABLE))
 354                 dev->capabilities |= PNP_DISABLE;
 355         dev->capabilities |= PNP_READ;
 356         if (pnpbios_is_dynamic(dev))
 357                 dev->capabilities |= PNP_WRITE;
 358         if (dev->flags & PNPBIOS_REMOVABLE)
 359                 dev->capabilities |= PNP_REMOVABLE;
 360         dev->protocol = &pnpbios_protocol;
 361
 362         /* clear out the damaged flags */
 363         if (!dev->active)
 364                 pnp_init_resource_table(&dev->res);
 365
 366         pnp_add_device(dev);
 367         pnpbios_interface_attach_device(node);
 368
 369         return 0;
 370 }
 371
 372 static void __init build_devlist(void)
 373 {
 374         u8 nodenum;
 375         unsigned int nodes_got = 0;
 376         unsigned int devs = 0;
 377         struct pnp_bios_node *node;
 378         struct pnp_dev *dev;
 379
 380         node = pnpbios_kmalloc(node_info.max_node_size, GFP_KERNEL);
 381         if (!node)
 382                 return;
 383
 384         for(nodenum=0; nodenum<0xff; ) {
 385                 u8 thisnodenum = nodenum;
 386                 /* eventually we will want to use PNPMODE_STATIC here but for now
 387                  * dynamic will help us catch buggy bioses to add to the blacklist.
 388                  */
 389                 if (!pnpbios_dont_use_current_config) {
 390                         if (pnp_bios_get_dev_node(&nodenum, (char )PNPMODE_DYNAMIC, node))
 391                                 break;
 392                 } else {
 393                         if (pnp_bios_get_dev_node(&nodenum, (char )PNPMODE_STATIC, node))
 394                                 break;
 395                 }
 396                 nodes_got++;
 397                 dev =  pnpbios_kmalloc(sizeof (struct pnp_dev), GFP_KERNEL);
 398                 if (!dev)
 399                         break;
 400                 if(insert_device(dev,node)<0)
 401                         kfree(dev);
 402                 else
 403                         devs++;
 404                 if (nodenum <= thisnodenum) {
 405                         printk(KERN_ERR "PnPBIOS: build_devlist: Node number 0x%x is out of sequence following node 0x%x. Aborting.\n", (unsigned int)nodenum, (unsigned int)thisnodenum);
 406                         break;
 407                 }
 408         }
 409         kfree(node);
 410
 411         printk(KERN_INFO "PnPBIOS: %i node%s reported by PnP BIOS; %i recorded by driver\n",
 412                 nodes_got, nodes_got != 1 ? "s" : "", devs);
 413 }
 414
 415 /*
 416  *
 417  * INIT AND EXIT
 418  *
 419  */
 420
 421 static int pnpbios_disabled; /* = 0 */
 422 int pnpbios_dont_use_current_config; /* = 0 */
 423
 424 #ifndef MODULE
 425 static int __init pnpbios_setup(char *str)
 426 {
 427         int invert;
 428
 429         while ((str != NULL) && (*str != '\0')) {
 430                 if (strncmp(str, "off", 3) == 0)
 431                         pnpbios_disabled=1;
 432                 if (strncmp(str, "on", 2) == 0)
 433                         pnpbios_disabled=0;
 434                 invert = (strncmp(str, "no-", 3) == 0);
 435                 if (invert)
 436                         str += 3;
 437                 if (strncmp(str, "curr", 4) == 0)
 438                         pnpbios_dont_use_current_config = invert;
 439                 str = strchr(str, ',');
 440                 if (str != NULL)
 441                         str += strspn(str, ", \t");
 442         }
 443
 444         return 1;
 445 }
 446
 447 __setup("pnpbios=", pnpbios_setup);
 448 #endif
 449
 450 /* PnP BIOS signature: "$PnP" */
 451 #define PNP_SIGNATURE   (('$' << 0) + ('P' << 8) + ('n' << 16) + ('P' << 24))
 452
 453 int __init pnpbios_probe_system(void)
 454 {
 455         union pnp_bios_install_struct *check;
 456         u8 sum;
 457         int length, i;
 458
 459         printk(KERN_INFO "PnPBIOS: Scanning system for PnP BIOS support...\n");
 460
 461         /*
 462          * Search the defined area (0xf0000-0xffff0) for a valid PnP BIOS
 463          * structure and, if one is found, sets up the selectors and
 464          * entry points
 465          */
 466         for (check = (union pnp_bios_install_struct *) __va(0xf0000);
 467              check < (union pnp_bios_install_struct *) __va(0xffff0);
 468              check = (void *)check + 16) {
 469                 if (check->fields.signature != PNP_SIGNATURE)
 470                         continue;
 471                 printk(KERN_INFO "PnPBIOS: Found PnP BIOS installation structure at 0x%p\n", check);
 472                 length = check->fields.length;
 473                 if (!length) {
 474                         printk(KERN_ERR "PnPBIOS: installation structure is invalid, skipping\n");
 475                         continue;
 476                 }
 477                 for (sum = 0, i = 0; i < length; i++)
 478                         sum += check->chars[i];
 479                 if (sum) {
 480                         printk(KERN_ERR "PnPBIOS: installation structure is corrupted, skipping\n");
 481                         continue;
 482                 }
 483                 if (check->fields.version < 0x10) {
 484                         printk(KERN_WARNING "PnPBIOS: PnP BIOS version %d.%d is not supported\n",
 485                                check->fields.version >> 4,
 486                                check->fields.version & 15);
 487                         continue;
 488                 }
 489                 printk(KERN_INFO "PnPBIOS: PnP BIOS version %d.%d, entry 0x%x:0x%x, dseg 0x%x\n",
 490                        check->fields.version >> 4, check->fields.version & 15,
 491                        check->fields.pm16cseg, check->fields.pm16offset,
 492                        check->fields.pm16dseg);
 493                 pnp_bios_install = check;
 494                 return 1;
 495         }
 496
 497         printk(KERN_INFO "PnPBIOS: PnP BIOS support was not detected.\n");
 498         return 0;
 499 }
 500
 501 int __init pnpbios_init(void)
 502 {
 503         int ret;
 504         if(pnpbios_disabled || (dmi_broken & BROKEN_PNP_BIOS)) {
 505                 printk(KERN_INFO "PnPBIOS: Disabled\n");
 506                 return -ENODEV;
 507         }
 508
 509         /* scan the system for pnpbios support */
 510         if (!pnpbios_probe_system())
 511                 return -ENODEV;
 512
 513         /* make preparations for bios calls */
 514         pnpbios_calls_init(pnp_bios_install);
 515
 516         /* read the node info */
 517         ret = pnp_bios_dev_node_info(&node_info);
 518         if (ret) {
 519                 printk(KERN_ERR "PnPBIOS: Unable to get node info.  Aborting.\n");
 520                 return ret;
 521         }
 522
 523         /* register with the pnp layer */
 524         ret = pnp_register_protocol(&pnpbios_protocol);
 525         if (ret) {
 526                 printk(KERN_ERR "PnPBIOS: Unable to register driver.  Aborting.\n");
 527                 return ret;
 528         }
 529
 530         /* start the proc interface */
 531         ret = pnpbios_proc_init();
 532         if (ret)
 533                 printk(KERN_ERR "PnPBIOS: Failed to create proc interface.\n");
 534
 535         /* scan for pnpbios devices */
 536         build_devlist();
 537
 538         return 0;
 539 }
 540
 541 subsys_initcall(pnpbios_init);
 542
 543 static int __init pnpbios_thread_init(void)
 544 {
 545 #ifdef CONFIG_HOTPLUG
 546         init_completion(&unload_sem);
 547         if (kernel_thread(pnp_dock_thread, NULL, CLONE_KERNEL) > 0)
 548                 unloading = 0;
 549 #endif
 550         return 0;
 551 }
 552
 553 #ifndef MODULE
 554
 555 /* init/main.c calls pnpbios_init early */
 556
 557 /* Start the kernel thread later: */
 558 module_init(pnpbios_thread_init);
 559
 560 #else
 561
 562 /*
 563  * N.B.: Building pnpbios as a module hasn't been fully implemented
 564  */
 565
 566 MODULE_LICENSE("GPL");
 567
 568 static int __init pnpbios_init_all(void)
 569 {
 570         int r;
 571
 572         r = pnpbios_init();
 573         if (r)
 574                 return r;
 575         r = pnpbios_thread_init();
 576         if (r)
 577                 return r;
 578         return 0;
 579 }
 580
 581 static void __exit pnpbios_exit(void)
 582 {
 583 #ifdef CONFIG_HOTPLUG
 584         unloading = 1;
 585         wait_for_completion(&unload_sem);
 586 #endif
 587         pnpbios_proc_exit();
 588         /* We ought to free resources here */
 589         return;
 590 }
 591
 592 module_init(pnpbios_init_all);
 593 module_exit(pnpbios_exit);
 594
 595 #endif
 596
 597 EXPORT_SYMBOL(pnpbios_protocol);