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
  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/completion.h>
  60 #include <linux/spinlock.h>
  61 #include <linux/dmi.h>
  62 #include <linux/delay.h>
  63 #include <linux/acpi.h>
  64 #include <linux/freezer.h>
  65
  66 #include <asm/page.h>
  67 #include <asm/desc.h>
  68 #include <asm/system.h>
  69 #include <asm/byteorder.h>
  70
  71 #include "pnpbios.h"
  72
  73
  74 /*
  75  *
  76  * PnP BIOS INTERFACE
  77  *
  78  */
  79
  80 static union pnp_bios_install_struct * pnp_bios_install = NULL;
  81
  82 int pnp_bios_present(void)
  83 {
  84         return (pnp_bios_install != NULL);
  85 }
  86
  87 struct pnp_dev_node_info node_info;
  88
  89 /*
  90  *
  91  * DOCKING FUNCTIONS
  92  *
  93  */
  94
  95 #ifdef CONFIG_HOTPLUG
  96
  97 static int unloading = 0;
  98 static struct completion unload_sem;
  99
 100 /*
 101  * (Much of this belongs in a shared routine somewhere)
 102  */
 103
 104 static int pnp_dock_event(int dock, struct pnp_docking_station_info *info)
 105 {
 106         char *argv [3], **envp, *buf, *scratch;
 107         int i = 0, value;
 108
 109         if (!current->fs->root) {
 110                 return -EAGAIN;
 111         }
 112         if (!(envp = kcalloc(20, sizeof (char *), GFP_KERNEL))) {
 113                 return -ENOMEM;
 114         }
 115         if (!(buf = kzalloc(256, GFP_KERNEL))) {
 116                 kfree (envp);
 117                 return -ENOMEM;
 118         }
 119
 120         /* FIXME: if there are actual users of this, it should be integrated into
 121          * the driver core and use the usual infrastructure like sysfs and uevents */
 122         argv [0] = "/sbin/pnpbios";
 123         argv [1] = "dock";
 124         argv [2] = NULL;
 125
 126         /* minimal command environment */
 127         envp [i++] = "HOME=/";
 128         envp [i++] = "PATH=/sbin:/bin:/usr/sbin:/usr/bin";
 129
 130 #ifdef  DEBUG
 131         /* hint that policy agent should enter no-stdout debug mode */
 132         envp [i++] = "DEBUG=kernel";
 133 #endif
 134         /* extensible set of named bus-specific parameters,
 135          * supporting multiple driver selection algorithms.
 136          */
 137         scratch = buf;
 138
 139         /* action:  add, remove */
 140         envp [i++] = scratch;
 141         scratch += sprintf (scratch, "ACTION=%s", dock?"add":"remove") + 1;
 142
 143         /* Report the ident for the dock */
 144         envp [i++] = scratch;
 145         scratch += sprintf (scratch, "DOCK=%x/%x/%x",
 146                 info->location_id, info->serial, info->capabilities);
 147         envp[i] = NULL;
 148
 149         value = call_usermodehelper (argv [0], argv, envp, 0);
 150         kfree (buf);
 151         kfree (envp);
 152         return 0;
 153 }
 154
 155 /*
 156  * Poll the PnP docking at regular intervals
 157  */
 158 static int pnp_dock_thread(void * unused)
 159 {
 160         static struct pnp_docking_station_info now;
 161         int docked = -1, d = 0;
 162         daemonize("kpnpbiosd");
 163         allow_signal(SIGKILL);
 164         while(!unloading && !signal_pending(current))
 165         {
 166                 int status;
 167
 168                 /*
 169                  * Poll every 2 seconds
 170                  */
 171                 msleep_interruptible(2000);
 172
 173                 if(signal_pending(current)) {
 174                         if (try_to_freeze())
 175                                 continue;
 176                         break;
 177                 }
 178
 179                 status = pnp_bios_dock_station_info(&now);
 180
 181                 switch(status)
 182                 {
 183                         /*
 184                          * No dock to manage
 185                          */
 186                         case PNP_FUNCTION_NOT_SUPPORTED:
 187                                 complete_and_exit(&unload_sem, 0);
 188                         case PNP_SYSTEM_NOT_DOCKED:
 189                                 d = 0;
 190                                 break;
 191                         case PNP_SUCCESS:
 192                                 d = 1;
 193                                 break;
 194                         default:
 195                                 pnpbios_print_status( "pnp_dock_thread", status );
 196                                 continue;
 197                 }
 198                 if(d != docked)
 199                 {
 200                         if(pnp_dock_event(d, &now)==0)
 201                         {
 202                                 docked = d;
 203 #if 0
 204                                 printk(KERN_INFO "PnPBIOS: Docking station %stached\n", docked?"at":"de");
 205 #endif
 206                         }
 207                 }
 208         }
 209         complete_and_exit(&unload_sem, 0);
 210 }
 211
 212 #endif   /* CONFIG_HOTPLUG */
 213
 214 static int pnpbios_get_resources(struct pnp_dev * dev, struct pnp_resource_table * res)
 215 {
 216         u8 nodenum = dev->number;
 217         struct pnp_bios_node * node;
 218
 219         /* just in case */
 220         if(!pnpbios_is_dynamic(dev))
 221                 return -EPERM;
 222
 223         node = kzalloc(node_info.max_node_size, GFP_KERNEL);
 224         if (!node)
 225                 return -1;
 226         if (pnp_bios_get_dev_node(&nodenum, (char )PNPMODE_DYNAMIC, node)) {
 227                 kfree(node);
 228                 return -ENODEV;
 229         }
 230         pnpbios_read_resources_from_node(res, node);
 231         dev->active = pnp_is_active(dev);
 232         kfree(node);
 233         return 0;
 234 }
 235
 236 static int pnpbios_set_resources(struct pnp_dev * dev, struct pnp_resource_table * res)
 237 {
 238         u8 nodenum = dev->number;
 239         struct pnp_bios_node * node;
 240         int ret;
 241
 242         /* just in case */
 243         if (!pnpbios_is_dynamic(dev))
 244                 return -EPERM;
 245
 246         node = kzalloc(node_info.max_node_size, GFP_KERNEL);
 247         if (!node)
 248                 return -1;
 249         if (pnp_bios_get_dev_node(&nodenum, (char )PNPMODE_DYNAMIC, node)) {
 250                 kfree(node);
 251                 return -ENODEV;
 252         }
 253         if(pnpbios_write_resources_to_node(res, node)<0) {
 254                 kfree(node);
 255                 return -1;
 256         }
 257         ret = pnp_bios_set_dev_node(node->handle, (char)PNPMODE_DYNAMIC, node);
 258         kfree(node);
 259         if (ret > 0)
 260                 ret = -1;
 261         return ret;
 262 }
 263
 264 static void pnpbios_zero_data_stream(struct pnp_bios_node * node)
 265 {
 266         unsigned char * p = (char *)node->data;
 267         unsigned char * end = (char *)(node->data + node->size);
 268         unsigned int len;
 269         int i;
 270         while ((char *)p < (char *)end) {
 271                 if(p[0] & 0x80) { /* large tag */
 272                         len = (p[2] << 8) | p[1];
 273                         p += 3;
 274                 } else {
 275                         if (((p[0]>>3) & 0x0f) == 0x0f)
 276                                 return;
 277                         len = p[0] & 0x07;
 278                         p += 1;
 279                 }
 280                 for (i = 0; i < len; i++)
 281                         p[i] = 0;
 282                 p += len;
 283         }
 284         printk(KERN_ERR "PnPBIOS: Resource structure did not contain an end tag.\n");
 285 }
 286
 287 static int pnpbios_disable_resources(struct pnp_dev *dev)
 288 {
 289         struct pnp_bios_node * node;
 290         u8 nodenum = dev->number;
 291         int ret;
 292
 293         /* just in case */
 294         if(dev->flags & PNPBIOS_NO_DISABLE || !pnpbios_is_dynamic(dev))
 295                 return -EPERM;
 296
 297         node = kzalloc(node_info.max_node_size, GFP_KERNEL);
 298         if (!node)
 299                 return -ENOMEM;
 300
 301         if (pnp_bios_get_dev_node(&nodenum, (char )PNPMODE_DYNAMIC, node)) {
 302                 kfree(node);
 303                 return -ENODEV;
 304         }
 305         pnpbios_zero_data_stream(node);
 306
 307         ret = pnp_bios_set_dev_node(dev->number, (char)PNPMODE_DYNAMIC, node);
 308         kfree(node);
 309         if (ret > 0)
 310                 ret = -1;
 311         return ret;
 312 }
 313
 314 /* PnP Layer support */
 315
 316 struct pnp_protocol pnpbios_protocol = {
 317         .name   = "Plug and Play BIOS",
 318         .get    = pnpbios_get_resources,
 319         .set    = pnpbios_set_resources,
 320         .disable = pnpbios_disable_resources,
 321 };
 322
 323 static int insert_device(struct pnp_dev *dev, struct pnp_bios_node * node)
 324 {
 325         struct list_head * pos;
 326         struct pnp_dev * pnp_dev;
 327         struct pnp_id *dev_id;
 328         char id[8];
 329
 330         /* check if the device is already added */
 331         dev->number = node->handle;
 332         list_for_each (pos, &pnpbios_protocol.devices){
 333                 pnp_dev = list_entry(pos, struct pnp_dev, protocol_list);
 334                 if (dev->number == pnp_dev->number)
 335                         return -1;
 336         }
 337
 338         /* set the initial values for the PnP device */
 339         dev_id = kzalloc(sizeof(struct pnp_id), GFP_KERNEL);
 340         if (!dev_id)
 341                 return -1;
 342         pnpid32_to_pnpid(node->eisa_id,id);
 343         memcpy(dev_id->id,id,7);
 344         pnp_add_id(dev_id, dev);
 345         pnpbios_parse_data_stream(dev, node);
 346         dev->active = pnp_is_active(dev);
 347         dev->flags = node->flags;
 348         if (!(dev->flags & PNPBIOS_NO_CONFIG))
 349                 dev->capabilities |= PNP_CONFIGURABLE;
 350         if (!(dev->flags & PNPBIOS_NO_DISABLE) && pnpbios_is_dynamic(dev))
 351                 dev->capabilities |= PNP_DISABLE;
 352         dev->capabilities |= PNP_READ;
 353         if (pnpbios_is_dynamic(dev))
 354                 dev->capabilities |= PNP_WRITE;
 355         if (dev->flags & PNPBIOS_REMOVABLE)
 356                 dev->capabilities |= PNP_REMOVABLE;
 357         dev->protocol = &pnpbios_protocol;
 358
 359         /* clear out the damaged flags */
 360         if (!dev->active)
 361                 pnp_init_resource_table(&dev->res);
 362
 363         pnp_add_device(dev);
 364         pnpbios_interface_attach_device(node);
 365
 366         return 0;
 367 }
 368
 369 static void __init build_devlist(void)
 370 {
 371         u8 nodenum;
 372         unsigned int nodes_got = 0;
 373         unsigned int devs = 0;
 374         struct pnp_bios_node *node;
 375         struct pnp_dev *dev;
 376
 377         node = kzalloc(node_info.max_node_size, GFP_KERNEL);
 378         if (!node)
 379                 return;
 380
 381         for(nodenum=0; nodenum<0xff; ) {
 382                 u8 thisnodenum = nodenum;
 383                 /* eventually we will want to use PNPMODE_STATIC here but for now
 384                  * dynamic will help us catch buggy bioses to add to the blacklist.
 385                  */
 386                 if (!pnpbios_dont_use_current_config) {
 387                         if (pnp_bios_get_dev_node(&nodenum, (char )PNPMODE_DYNAMIC, node))
 388                                 break;
 389                 } else {
 390                         if (pnp_bios_get_dev_node(&nodenum, (char )PNPMODE_STATIC, node))
 391                                 break;
 392                 }
 393                 nodes_got++;
 394                 dev =  kzalloc(sizeof (struct pnp_dev), GFP_KERNEL);
 395                 if (!dev)
 396                         break;
 397                 if(insert_device(dev,node)<0)
 398                         kfree(dev);
 399                 else
 400                         devs++;
 401                 if (nodenum <= thisnodenum) {
 402                         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);
 403                         break;
 404                 }
 405         }
 406         kfree(node);
 407
 408         printk(KERN_INFO "PnPBIOS: %i node%s reported by PnP BIOS; %i recorded by driver\n",
 409                 nodes_got, nodes_got != 1 ? "s" : "", devs);
 410 }
 411
 412 /*
 413  *
 414  * INIT AND EXIT
 415  *
 416  */
 417
 418 static int pnpbios_disabled; /* = 0 */
 419 int pnpbios_dont_use_current_config; /* = 0 */
 420
 421 #ifndef MODULE
 422 static int __init pnpbios_setup(char *str)
 423 {
 424         int invert;
 425
 426         while ((str != NULL) && (*str != '\0')) {
 427                 if (strncmp(str, "off", 3) == 0)
 428                         pnpbios_disabled=1;
 429                 if (strncmp(str, "on", 2) == 0)
 430                         pnpbios_disabled=0;
 431                 invert = (strncmp(str, "no-", 3) == 0);
 432                 if (invert)
 433                         str += 3;
 434                 if (strncmp(str, "curr", 4) == 0)
 435                         pnpbios_dont_use_current_config = invert;
 436                 str = strchr(str, ',');
 437                 if (str != NULL)
 438                         str += strspn(str, ", \t");
 439         }
 440
 441         return 1;
 442 }
 443
 444 __setup("pnpbios=", pnpbios_setup);
 445 #endif
 446
 447 /* PnP BIOS signature: "$PnP" */
 448 #define PNP_SIGNATURE   (('$' << 0) + ('P' << 8) + ('n' << 16) + ('P' << 24))
 449
 450 static int __init pnpbios_probe_system(void)
 451 {
 452         union pnp_bios_install_struct *check;
 453         u8 sum;
 454         int length, i;
 455
 456         printk(KERN_INFO "PnPBIOS: Scanning system for PnP BIOS support...\n");
 457
 458         /*
 459          * Search the defined area (0xf0000-0xffff0) for a valid PnP BIOS
 460          * structure and, if one is found, sets up the selectors and
 461          * entry points
 462          */
 463         for (check = (union pnp_bios_install_struct *) __va(0xf0000);
 464              check < (union pnp_bios_install_struct *) __va(0xffff0);
 465              check = (void *)check + 16) {
 466                 if (check->fields.signature != PNP_SIGNATURE)
 467                         continue;
 468                 printk(KERN_INFO "PnPBIOS: Found PnP BIOS installation structure at 0x%p\n", check);
 469                 length = check->fields.length;
 470                 if (!length) {
 471                         printk(KERN_ERR "PnPBIOS: installation structure is invalid, skipping\n");
 472                         continue;
 473                 }
 474                 for (sum = 0, i = 0; i < length; i++)
 475                         sum += check->chars[i];
 476                 if (sum) {
 477                         printk(KERN_ERR "PnPBIOS: installation structure is corrupted, skipping\n");
 478                         continue;
 479                 }
 480                 if (check->fields.version < 0x10) {
 481                         printk(KERN_WARNING "PnPBIOS: PnP BIOS version %d.%d is not supported\n",
 482                                check->fields.version >> 4,
 483                                check->fields.version & 15);
 484                         continue;
 485                 }
 486                 printk(KERN_INFO "PnPBIOS: PnP BIOS version %d.%d, entry 0x%x:0x%x, dseg 0x%x\n",
 487                        check->fields.version >> 4, check->fields.version & 15,
 488                        check->fields.pm16cseg, check->fields.pm16offset,
 489                        check->fields.pm16dseg);
 490                 pnp_bios_install = check;
 491                 return 1;
 492         }
 493
 494         printk(KERN_INFO "PnPBIOS: PnP BIOS support was not detected.\n");
 495         return 0;
 496 }
 497
 498 static int __init exploding_pnp_bios(struct dmi_system_id *d)
 499 {
 500         printk(KERN_WARNING "%s detected. Disabling PnPBIOS\n", d->ident);
 501         return 0;
 502 }
 503
 504 static struct dmi_system_id pnpbios_dmi_table[] __initdata = {
 505         {       /* PnPBIOS GPF on boot */
 506                 .callback = exploding_pnp_bios,
 507                 .ident = "Higraded P14H",
 508                 .matches = {
 509                         DMI_MATCH(DMI_BIOS_VENDOR, "American Megatrends Inc."),
 510                         DMI_MATCH(DMI_BIOS_VERSION, "07.00T"),
 511                         DMI_MATCH(DMI_SYS_VENDOR, "Higraded"),
 512                         DMI_MATCH(DMI_PRODUCT_NAME, "P14H"),
 513                 },
 514         },
 515         {       /* PnPBIOS GPF on boot */
 516                 .callback = exploding_pnp_bios,
 517                 .ident = "ASUS P4P800",
 518                 .matches = {
 519                         DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer Inc."),
 520                         DMI_MATCH(DMI_BOARD_NAME, "P4P800"),
 521                 },
 522         },
 523         { }
 524 };
 525
 526 static int __init pnpbios_init(void)
 527 {
 528         int ret;
 529
 530 #if defined(CONFIG_PPC_MERGE)
 531         if (check_legacy_ioport(PNPBIOS_BASE))
 532                 return -ENODEV;
 533 #endif
 534         if (pnpbios_disabled || dmi_check_system(pnpbios_dmi_table) ||
 535             paravirt_enabled()) {
 536                 printk(KERN_INFO "PnPBIOS: Disabled\n");
 537                 return -ENODEV;
 538         }
 539
 540 #ifdef CONFIG_PNPACPI
 541         if (!acpi_disabled && !pnpacpi_disabled) {
 542                 pnpbios_disabled = 1;
 543                 printk(KERN_INFO "PnPBIOS: Disabled by ACPI PNP\n");
 544                 return -ENODEV;
 545         }
 546 #endif /* CONFIG_ACPI */
 547
 548         /* scan the system for pnpbios support */
 549         if (!pnpbios_probe_system())
 550                 return -ENODEV;
 551
 552         /* make preparations for bios calls */
 553         pnpbios_calls_init(pnp_bios_install);
 554
 555         /* read the node info */
 556         ret = pnp_bios_dev_node_info(&node_info);
 557         if (ret) {
 558                 printk(KERN_ERR "PnPBIOS: Unable to get node info.  Aborting.\n");
 559                 return ret;
 560         }
 561
 562         /* register with the pnp layer */
 563         ret = pnp_register_protocol(&pnpbios_protocol);
 564         if (ret) {
 565                 printk(KERN_ERR "PnPBIOS: Unable to register driver.  Aborting.\n");
 566                 return ret;
 567         }
 568
 569         /* start the proc interface */
 570         ret = pnpbios_proc_init();
 571         if (ret)
 572                 printk(KERN_ERR "PnPBIOS: Failed to create proc interface.\n");
 573
 574         /* scan for pnpbios devices */
 575         build_devlist();
 576
 577         return 0;
 578 }
 579
 580 subsys_initcall(pnpbios_init);
 581
 582 static int __init pnpbios_thread_init(void)
 583 {
 584 #if defined(CONFIG_PPC_MERGE)
 585         if (check_legacy_ioport(PNPBIOS_BASE))
 586                 return 0;
 587 #endif
 588         if (pnpbios_disabled)
 589                 return 0;
 590 #ifdef CONFIG_HOTPLUG
 591         init_completion(&unload_sem);
 592         if (kernel_thread(pnp_dock_thread, NULL, CLONE_KERNEL) > 0)
 593                 unloading = 0;
 594 #endif
 595         return 0;
 596 }
 597
 598 #ifndef MODULE
 599
 600 /* init/main.c calls pnpbios_init early */
 601
 602 /* Start the kernel thread later: */
 603 module_init(pnpbios_thread_init);
 604
 605 #else
 606
 607 /*
 608  * N.B.: Building pnpbios as a module hasn't been fully implemented
 609  */
 610
 611 MODULE_LICENSE("GPL");
 612
 613 static int __init pnpbios_init_all(void)
 614 {
 615         int r;
 616
 617         r = pnpbios_init();
 618         if (r)
 619                 return r;
 620         r = pnpbios_thread_init();
 621         if (r)
 622                 return r;
 623         return 0;
 624 }
 625
 626 static void __exit pnpbios_exit(void)
 627 {
 628 #ifdef CONFIG_HOTPLUG
 629         unloading = 1;
 630         wait_for_completion(&unload_sem);
 631 #endif
 632         pnpbios_proc_exit();
 633         /* We ought to free resources here */
 634         return;
 635 }
 636
 637 module_init(pnpbios_init_all);
 638 module_exit(pnpbios_exit);
 639
 640 #endif
 641
 642 EXPORT_SYMBOL(pnpbios_protocol);