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