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