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