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 #include <linux/kthread.h>
  66
  67 #include <asm/page.h>
  68 #include <asm/desc.h>
  69 #include <asm/system.h>
  70 #include <asm/byteorder.h>
  71
  72 #include "../base.h"
  73 #include "pnpbios.h"
  74
  75 /*
  76  *
  77  * PnP BIOS INTERFACE
  78  *
  79  */
  80
  81 static union pnp_bios_install_struct *pnp_bios_install = NULL;
  82
  83 int pnp_bios_present(void)
  84 {
  85         return (pnp_bios_install != NULL);
  86 }
  87
  88 struct pnp_dev_node_info node_info;
  89
  90 /*
  91  *
  92  * DOCKING FUNCTIONS
  93  *
  94  */
  95
  96 #ifdef CONFIG_HOTPLUG
  97
  98 static int unloading = 0;
  99 static struct completion unload_sem;
 100
 101 /*
 102  * (Much of this belongs in a shared routine somewhere)
 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 (!(envp = kcalloc(20, sizeof(char *), GFP_KERNEL)))
 110                 return -ENOMEM;
 111         if (!(buf = kzalloc(256, GFP_KERNEL))) {
 112                 kfree(envp);
 113                 return -ENOMEM;
 114         }
 115
 116         /* FIXME: if there are actual users of this, it should be
 117          * integrated into the driver core and use the usual infrastructure
 118          * like sysfs and uevents
 119          */
 120         argv[0] = "/sbin/pnpbios";
 121         argv[1] = "dock";
 122         argv[2] = NULL;
 123
 124         /* minimal command environment */
 125         envp[i++] = "HOME=/";
 126         envp[i++] = "PATH=/sbin:/bin:/usr/sbin:/usr/bin";
 127
 128 #ifdef  DEBUG
 129         /* hint that policy agent should enter no-stdout debug mode */
 130         envp[i++] = "DEBUG=kernel";
 131 #endif
 132         /* extensible set of named bus-specific parameters,
 133          * supporting multiple driver selection algorithms.
 134          */
 135         scratch = buf;
 136
 137         /* action:  add, remove */
 138         envp[i++] = scratch;
 139         scratch += sprintf(scratch, "ACTION=%s", dock ? "add" : "remove") + 1;
 140
 141         /* Report the ident for the dock */
 142         envp[i++] = scratch;
 143         scratch += sprintf(scratch, "DOCK=%x/%x/%x",
 144                            info->location_id, info->serial, info->capabilities);
 145         envp[i] = NULL;
 146
 147         value = call_usermodehelper(argv [0], argv, envp, UMH_WAIT_EXEC);
 148         kfree(buf);
 149         kfree(envp);
 150         return 0;
 151 }
 152
 153 /*
 154  * Poll the PnP docking at regular intervals
 155  */
 156 static int pnp_dock_thread(void *unused)
 157 {
 158         static struct pnp_docking_station_info now;
 159         int docked = -1, d = 0;
 160
 161         set_freezable();
 162         while (!unloading) {
 163                 int status;
 164
 165                 /*
 166                  * Poll every 2 seconds
 167                  */
 168                 msleep_interruptible(2000);
 169
 170                 if (try_to_freeze())
 171                         continue;
 172
 173                 status = pnp_bios_dock_station_info(&now);
 174
 175                 switch (status) {
 176                         /*
 177                          * No dock to manage
 178                          */
 179                 case PNP_FUNCTION_NOT_SUPPORTED:
 180                         complete_and_exit(&unload_sem, 0);
 181                 case PNP_SYSTEM_NOT_DOCKED:
 182                         d = 0;
 183                         break;
 184                 case PNP_SUCCESS:
 185                         d = 1;
 186                         break;
 187                 default:
 188                         pnpbios_print_status("pnp_dock_thread", status);
 189                         continue;
 190                 }
 191                 if (d != docked) {
 192                         if (pnp_dock_event(d, &now) == 0) {
 193                                 docked = d;
 194 #if 0
 195                                 printk(KERN_INFO
 196                                        "PnPBIOS: Docking station %stached\n",
 197                                        docked ? "at" : "de");
 198 #endif
 199                         }
 200                 }
 201         }
 202         complete_and_exit(&unload_sem, 0);
 203 }
 204
 205 #endif                          /* CONFIG_HOTPLUG */
 206
 207 static int pnpbios_get_resources(struct pnp_dev *dev)
 208 {
 209         u8 nodenum = dev->number;
 210         struct pnp_bios_node *node;
 211
 212         if (!pnpbios_is_dynamic(dev))
 213                 return -EPERM;
 214
 215         dev_dbg(&dev->dev, "get resources\n");
 216         node = kzalloc(node_info.max_node_size, GFP_KERNEL);
 217         if (!node)
 218                 return -1;
 219         if (pnp_bios_get_dev_node(&nodenum, (char)PNPMODE_DYNAMIC, node)) {
 220                 kfree(node);
 221                 return -ENODEV;
 222         }
 223         pnpbios_read_resources_from_node(dev, node);
 224         dev->active = pnp_is_active(dev);
 225         kfree(node);
 226         return 0;
 227 }
 228
 229 static int pnpbios_set_resources(struct pnp_dev *dev)
 230 {
 231         u8 nodenum = dev->number;
 232         struct pnp_bios_node *node;
 233         int ret;
 234
 235         if (!pnpbios_is_dynamic(dev))
 236                 return -EPERM;
 237
 238         dev_dbg(&dev->dev, "set resources\n");
 239         node = kzalloc(node_info.max_node_size, GFP_KERNEL);
 240         if (!node)
 241                 return -1;
 242         if (pnp_bios_get_dev_node(&nodenum, (char)PNPMODE_DYNAMIC, node)) {
 243                 kfree(node);
 244                 return -ENODEV;
 245         }
 246         if (pnpbios_write_resources_to_node(dev, node) < 0) {
 247                 kfree(node);
 248                 return -1;
 249         }
 250         ret = pnp_bios_set_dev_node(node->handle, (char)PNPMODE_DYNAMIC, node);
 251         kfree(node);
 252         if (ret > 0)
 253                 ret = -1;
 254         return ret;
 255 }
 256
 257 static void pnpbios_zero_data_stream(struct pnp_bios_node *node)
 258 {
 259         unsigned char *p = (char *)node->data;
 260         unsigned char *end = (char *)(node->data + node->size);
 261         unsigned int len;
 262         int i;
 263
 264         while ((char *)p < (char *)end) {
 265                 if (p[0] & 0x80) {      /* large tag */
 266                         len = (p[2] << 8) | p[1];
 267                         p += 3;
 268                 } else {
 269                         if (((p[0] >> 3) & 0x0f) == 0x0f)
 270                                 return;
 271                         len = p[0] & 0x07;
 272                         p += 1;
 273                 }
 274                 for (i = 0; i < len; i++)
 275                         p[i] = 0;
 276                 p += len;
 277         }
 278         printk(KERN_ERR
 279                "PnPBIOS: Resource structure did not contain an end tag.\n");
 280 }
 281
 282 static int pnpbios_disable_resources(struct pnp_dev *dev)
 283 {
 284         struct pnp_bios_node *node;
 285         u8 nodenum = dev->number;
 286         int ret;
 287
 288         if (dev->flags & PNPBIOS_NO_DISABLE || !pnpbios_is_dynamic(dev))
 289                 return -EPERM;
 290
 291         node = kzalloc(node_info.max_node_size, GFP_KERNEL);
 292         if (!node)
 293                 return -ENOMEM;
 294
 295         if (pnp_bios_get_dev_node(&nodenum, (char)PNPMODE_DYNAMIC, node)) {
 296                 kfree(node);
 297                 return -ENODEV;
 298         }
 299         pnpbios_zero_data_stream(node);
 300
 301         ret = pnp_bios_set_dev_node(dev->number, (char)PNPMODE_DYNAMIC, node);
 302         kfree(node);
 303         if (ret > 0)
 304                 ret = -1;
 305         return ret;
 306 }
 307
 308 /* PnP Layer support */
 309
 310 struct pnp_protocol pnpbios_protocol = {
 311         .name = "Plug and Play BIOS",
 312         .get = pnpbios_get_resources,
 313         .set = pnpbios_set_resources,
 314         .disable = pnpbios_disable_resources,
 315 };
 316
 317 static int __init insert_device(struct pnp_bios_node *node)
 318 {
 319         struct list_head *pos;
 320         struct pnp_dev *dev;
 321         char id[8];
 322
 323         /* check if the device is already added */
 324         list_for_each(pos, &pnpbios_protocol.devices) {
 325                 dev = list_entry(pos, struct pnp_dev, protocol_list);
 326                 if (dev->number == node->handle)
 327                         return -1;
 328         }
 329
 330         pnp_eisa_id_to_string(node->eisa_id & PNP_EISA_ID_MASK, id);
 331         dev = pnp_alloc_dev(&pnpbios_protocol, node->handle, id);
 332         if (!dev)
 333                 return -1;
 334
 335         pnpbios_parse_data_stream(dev, node);
 336         dev->active = pnp_is_active(dev);
 337         dev->flags = node->flags;
 338         if (!(dev->flags & PNPBIOS_NO_CONFIG))
 339                 dev->capabilities |= PNP_CONFIGURABLE;
 340         if (!(dev->flags & PNPBIOS_NO_DISABLE) && pnpbios_is_dynamic(dev))
 341                 dev->capabilities |= PNP_DISABLE;
 342         dev->capabilities |= PNP_READ;
 343         if (pnpbios_is_dynamic(dev))
 344                 dev->capabilities |= PNP_WRITE;
 345         if (dev->flags & PNPBIOS_REMOVABLE)
 346                 dev->capabilities |= PNP_REMOVABLE;
 347
 348         /* clear out the damaged flags */
 349         if (!dev->active)
 350                 pnp_init_resources(dev);
 351
 352         pnp_add_device(dev);
 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 defined(CONFIG_PPC_MERGE)
 524         if (check_legacy_ioport(PNPBIOS_BASE))
 525                 return -ENODEV;
 526 #endif
 527         if (pnpbios_disabled || dmi_check_system(pnpbios_dmi_table) ||
 528             paravirt_enabled()) {
 529                 printk(KERN_INFO "PnPBIOS: Disabled\n");
 530                 return -ENODEV;
 531         }
 532 #ifdef CONFIG_PNPACPI
 533         if (!acpi_disabled && !pnpacpi_disabled) {
 534                 pnpbios_disabled = 1;
 535                 printk(KERN_INFO "PnPBIOS: Disabled by ACPI PNP\n");
 536                 return -ENODEV;
 537         }
 538 #endif                          /* CONFIG_ACPI */
 539
 540         /* scan the system for pnpbios support */
 541         if (!pnpbios_probe_system())
 542                 return -ENODEV;
 543
 544         /* make preparations for bios calls */
 545         pnpbios_calls_init(pnp_bios_install);
 546
 547         /* read the node info */
 548         ret = pnp_bios_dev_node_info(&node_info);
 549         if (ret) {
 550                 printk(KERN_ERR
 551                        "PnPBIOS: Unable to get node info.  Aborting.\n");
 552                 return ret;
 553         }
 554
 555         /* register with the pnp layer */
 556         ret = pnp_register_protocol(&pnpbios_protocol);
 557         if (ret) {
 558                 printk(KERN_ERR
 559                        "PnPBIOS: Unable to register driver.  Aborting.\n");
 560                 return ret;
 561         }
 562
 563         /* start the proc interface */
 564         ret = pnpbios_proc_init();
 565         if (ret)
 566                 printk(KERN_ERR "PnPBIOS: Failed to create proc interface.\n");
 567
 568         /* scan for pnpbios devices */
 569         build_devlist();
 570
 571         pnp_platform_devices = 1;
 572         return 0;
 573 }
 574
 575 subsys_initcall(pnpbios_init);
 576
 577 static int __init pnpbios_thread_init(void)
 578 {
 579         struct task_struct *task;
 580
 581 #if defined(CONFIG_PPC_MERGE)
 582         if (check_legacy_ioport(PNPBIOS_BASE))
 583                 return 0;
 584 #endif
 585         if (pnpbios_disabled)
 586                 return 0;
 587 #ifdef CONFIG_HOTPLUG
 588         init_completion(&unload_sem);
 589         task = kthread_run(pnp_dock_thread, NULL, "kpnpbiosd");
 590         if (!IS_ERR(task))
 591                 unloading = 0;
 592 #endif
 593         return 0;
 594 }
 595
 596 /* Start the kernel thread later: */
 597 module_init(pnpbios_thread_init);
 598
 599 EXPORT_SYMBOL(pnpbios_protocol);