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                         continue;
 185                 }
 186                 if (d != docked) {
 187                         if (pnp_dock_event(d, &now) == 0) {
 188                                 docked = d;
 189 #if 0
 190                                 printk(KERN_INFO
 191                                        "PnPBIOS: Docking station %stached\n",
 192                                        docked ? "at" : "de");
 193 #endif
 194                         }
 195                 }
 196         }
 197         complete_and_exit(&unload_sem, 0);
 198 }
 199
 200 static int pnpbios_get_resources(struct pnp_dev *dev)
 201 {
 202         u8 nodenum = dev->number;
 203         struct pnp_bios_node *node;
 204
 205         if (!pnpbios_is_dynamic(dev))
 206                 return -EPERM;
 207
 208         pnp_dbg(&dev->dev, "get resources\n");
 209         node = kzalloc(node_info.max_node_size, GFP_KERNEL);
 210         if (!node)
 211                 return -1;
 212         if (pnp_bios_get_dev_node(&nodenum, (char)PNPMODE_DYNAMIC, node)) {
 213                 kfree(node);
 214                 return -ENODEV;
 215         }
 216         pnpbios_read_resources_from_node(dev, node);
 217         dev->active = pnp_is_active(dev);
 218         kfree(node);
 219         return 0;
 220 }
 221
 222 static int pnpbios_set_resources(struct pnp_dev *dev)
 223 {
 224         u8 nodenum = dev->number;
 225         struct pnp_bios_node *node;
 226         int ret;
 227
 228         if (!pnpbios_is_dynamic(dev))
 229                 return -EPERM;
 230
 231         pnp_dbg(&dev->dev, "set resources\n");
 232         node = kzalloc(node_info.max_node_size, GFP_KERNEL);
 233         if (!node)
 234                 return -1;
 235         if (pnp_bios_get_dev_node(&nodenum, (char)PNPMODE_DYNAMIC, node)) {
 236                 kfree(node);
 237                 return -ENODEV;
 238         }
 239         if (pnpbios_write_resources_to_node(dev, node) < 0) {
 240                 kfree(node);
 241                 return -1;
 242         }
 243         ret = pnp_bios_set_dev_node(node->handle, (char)PNPMODE_DYNAMIC, node);
 244         kfree(node);
 245         if (ret > 0)
 246                 ret = -1;
 247         return ret;
 248 }
 249
 250 static void pnpbios_zero_data_stream(struct pnp_bios_node *node)
 251 {
 252         unsigned char *p = (char *)node->data;
 253         unsigned char *end = (char *)(node->data + node->size);
 254         unsigned int len;
 255         int i;
 256
 257         while ((char *)p < (char *)end) {
 258                 if (p[0] & 0x80) {      /* large tag */
 259                         len = (p[2] << 8) | p[1];
 260                         p += 3;
 261                 } else {
 262                         if (((p[0] >> 3) & 0x0f) == 0x0f)
 263                                 return;
 264                         len = p[0] & 0x07;
 265                         p += 1;
 266                 }
 267                 for (i = 0; i < len; i++)
 268                         p[i] = 0;
 269                 p += len;
 270         }
 271         printk(KERN_ERR
 272                "PnPBIOS: Resource structure did not contain an end tag.\n");
 273 }
 274
 275 static int pnpbios_disable_resources(struct pnp_dev *dev)
 276 {
 277         struct pnp_bios_node *node;
 278         u8 nodenum = dev->number;
 279         int ret;
 280
 281         if (dev->flags & PNPBIOS_NO_DISABLE || !pnpbios_is_dynamic(dev))
 282                 return -EPERM;
 283
 284         node = kzalloc(node_info.max_node_size, GFP_KERNEL);
 285         if (!node)
 286                 return -ENOMEM;
 287
 288         if (pnp_bios_get_dev_node(&nodenum, (char)PNPMODE_DYNAMIC, node)) {
 289                 kfree(node);
 290                 return -ENODEV;
 291         }
 292         pnpbios_zero_data_stream(node);
 293
 294         ret = pnp_bios_set_dev_node(dev->number, (char)PNPMODE_DYNAMIC, node);
 295         kfree(node);
 296         if (ret > 0)
 297                 ret = -1;
 298         return ret;
 299 }
 300
 301 /* PnP Layer support */
 302
 303 struct pnp_protocol pnpbios_protocol = {
 304         .name = "Plug and Play BIOS",
 305         .get = pnpbios_get_resources,
 306         .set = pnpbios_set_resources,
 307         .disable = pnpbios_disable_resources,
 308 };
 309
 310 static int __init insert_device(struct pnp_bios_node *node)
 311 {
 312         struct list_head *pos;
 313         struct pnp_dev *dev;
 314         char id[8];
 315         int error;
 316
 317         /* check if the device is already added */
 318         list_for_each(pos, &pnpbios_protocol.devices) {
 319                 dev = list_entry(pos, struct pnp_dev, protocol_list);
 320                 if (dev->number == node->handle)
 321                         return -EEXIST;
 322         }
 323
 324         pnp_eisa_id_to_string(node->eisa_id & PNP_EISA_ID_MASK, id);
 325         dev = pnp_alloc_dev(&pnpbios_protocol, node->handle, id);
 326         if (!dev)
 327                 return -ENOMEM;
 328
 329         pnpbios_parse_data_stream(dev, node);
 330         dev->active = pnp_is_active(dev);
 331         dev->flags = node->flags;
 332         if (!(dev->flags & PNPBIOS_NO_CONFIG))
 333                 dev->capabilities |= PNP_CONFIGURABLE;
 334         if (!(dev->flags & PNPBIOS_NO_DISABLE) && pnpbios_is_dynamic(dev))
 335                 dev->capabilities |= PNP_DISABLE;
 336         dev->capabilities |= PNP_READ;
 337         if (pnpbios_is_dynamic(dev))
 338                 dev->capabilities |= PNP_WRITE;
 339         if (dev->flags & PNPBIOS_REMOVABLE)
 340                 dev->capabilities |= PNP_REMOVABLE;
 341
 342         /* clear out the damaged flags */
 343         if (!dev->active)
 344                 pnp_init_resources(dev);
 345
 346         error = pnp_add_device(dev);
 347         if (error) {
 348                 put_device(&dev->dev);
 349                 return error;
 350         }
 351
 352         pnpbios_interface_attach_device(node);
 353
 354         return 0;
 355 }
 356
 357 static void __init build_devlist(void)
 358 {
 359         u8 nodenum;
 360         unsigned int nodes_got = 0;
 361         unsigned int devs = 0;
 362         struct pnp_bios_node *node;
 363
 364         node = kzalloc(node_info.max_node_size, GFP_KERNEL);
 365         if (!node)
 366                 return;
 367
 368         for (nodenum = 0; nodenum < 0xff;) {
 369                 u8 thisnodenum = nodenum;
 370                 /* eventually we will want to use PNPMODE_STATIC here but for now
 371                  * dynamic will help us catch buggy bioses to add to the blacklist.
 372                  */
 373                 if (!pnpbios_dont_use_current_config) {
 374                         if (pnp_bios_get_dev_node
 375                             (&nodenum, (char)PNPMODE_DYNAMIC, node))
 376                                 break;
 377                 } else {
 378                         if (pnp_bios_get_dev_node
 379                             (&nodenum, (char)PNPMODE_STATIC, node))
 380                                 break;
 381                 }
 382                 nodes_got++;
 383                 if (insert_device(node) == 0)
 384                         devs++;
 385                 if (nodenum <= thisnodenum) {
 386                         printk(KERN_ERR
 387                                "PnPBIOS: build_devlist: Node number 0x%x is out of sequence following node 0x%x. Aborting.\n",
 388                                (unsigned int)nodenum,
 389                                (unsigned int)thisnodenum);
 390                         break;
 391                 }
 392         }
 393         kfree(node);
 394
 395         printk(KERN_INFO
 396                "PnPBIOS: %i node%s reported by PnP BIOS; %i recorded by driver\n",
 397                nodes_got, nodes_got != 1 ? "s" : "", devs);
 398 }
 399
 400 /*
 401  *
 402  * INIT AND EXIT
 403  *
 404  */
 405
 406 static int pnpbios_disabled;
 407 int pnpbios_dont_use_current_config;
 408
 409 static int __init pnpbios_setup(char *str)
 410 {
 411         int invert;
 412
 413         while ((str != NULL) && (*str != '\0')) {
 414                 if (strncmp(str, "off", 3) == 0)
 415                         pnpbios_disabled = 1;
 416                 if (strncmp(str, "on", 2) == 0)
 417                         pnpbios_disabled = 0;
 418                 invert = (strncmp(str, "no-", 3) == 0);
 419                 if (invert)
 420                         str += 3;
 421                 if (strncmp(str, "curr", 4) == 0)
 422                         pnpbios_dont_use_current_config = invert;
 423                 str = strchr(str, ',');
 424                 if (str != NULL)
 425                         str += strspn(str, ", \t");
 426         }
 427
 428         return 1;
 429 }
 430
 431 __setup("pnpbios=", pnpbios_setup);
 432
 433 /* PnP BIOS signature: "$PnP" */
 434 #define PNP_SIGNATURE   (('$' << 0) + ('P' << 8) + ('n' << 16) + ('P' << 24))
 435
 436 static int __init pnpbios_probe_system(void)
 437 {
 438         union pnp_bios_install_struct *check;
 439         u8 sum;
 440         int length, i;
 441
 442         printk(KERN_INFO "PnPBIOS: Scanning system for PnP BIOS support...\n");
 443
 444         /*
 445          * Search the defined area (0xf0000-0xffff0) for a valid PnP BIOS
 446          * structure and, if one is found, sets up the selectors and
 447          * entry points
 448          */
 449         for (check = (union pnp_bios_install_struct *)__va(0xf0000);
 450              check < (union pnp_bios_install_struct *)__va(0xffff0);
 451              check = (void *)check + 16) {
 452                 if (check->fields.signature != PNP_SIGNATURE)
 453                         continue;
 454                 printk(KERN_INFO
 455                        "PnPBIOS: Found PnP BIOS installation structure at 0x%p\n",
 456                        check);
 457                 length = check->fields.length;
 458                 if (!length) {
 459                         printk(KERN_ERR
 460                                "PnPBIOS: installation structure is invalid, skipping\n");
 461                         continue;
 462                 }
 463                 for (sum = 0, i = 0; i < length; i++)
 464                         sum += check->chars[i];
 465                 if (sum) {
 466                         printk(KERN_ERR
 467                                "PnPBIOS: installation structure is corrupted, skipping\n");
 468                         continue;
 469                 }
 470                 if (check->fields.version < 0x10) {
 471                         printk(KERN_WARNING
 472                                "PnPBIOS: PnP BIOS version %d.%d is not supported\n",
 473                                check->fields.version >> 4,
 474                                check->fields.version & 15);
 475                         continue;
 476                 }
 477                 printk(KERN_INFO
 478                        "PnPBIOS: PnP BIOS version %d.%d, entry 0x%x:0x%x, dseg 0x%x\n",
 479                        check->fields.version >> 4, check->fields.version & 15,
 480                        check->fields.pm16cseg, check->fields.pm16offset,
 481                        check->fields.pm16dseg);
 482                 pnp_bios_install = check;
 483                 return 1;
 484         }
 485
 486         printk(KERN_INFO "PnPBIOS: PnP BIOS support was not detected.\n");
 487         return 0;
 488 }
 489
 490 static int __init exploding_pnp_bios(const struct dmi_system_id *d)
 491 {
 492         printk(KERN_WARNING "%s detected. Disabling PnPBIOS\n", d->ident);
 493         return 0;
 494 }
 495
 496 static struct dmi_system_id pnpbios_dmi_table[] __initdata = {
 497         {                       /* PnPBIOS GPF on boot */
 498          .callback = exploding_pnp_bios,
 499          .ident = "Higraded P14H",
 500          .matches = {
 501                      DMI_MATCH(DMI_BIOS_VENDOR, "American Megatrends Inc."),
 502                      DMI_MATCH(DMI_BIOS_VERSION, "07.00T"),
 503                      DMI_MATCH(DMI_SYS_VENDOR, "Higraded"),
 504                      DMI_MATCH(DMI_PRODUCT_NAME, "P14H"),
 505                      },
 506          },
 507         {                       /* PnPBIOS GPF on boot */
 508          .callback = exploding_pnp_bios,
 509          .ident = "ASUS P4P800",
 510          .matches = {
 511                      DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer Inc."),
 512                      DMI_MATCH(DMI_BOARD_NAME, "P4P800"),
 513                      },
 514          },
 515         {}
 516 };
 517
 518 static int __init pnpbios_init(void)
 519 {
 520         int ret;
 521
 522         if (pnpbios_disabled || dmi_check_system(pnpbios_dmi_table) ||
 523             paravirt_enabled()) {
 524                 printk(KERN_INFO "PnPBIOS: Disabled\n");
 525                 return -ENODEV;
 526         }
 527 #ifdef CONFIG_PNPACPI
 528         if (!acpi_disabled && !pnpacpi_disabled) {
 529                 pnpbios_disabled = 1;
 530                 printk(KERN_INFO "PnPBIOS: Disabled by ACPI PNP\n");
 531                 return -ENODEV;
 532         }
 533 #endif                          /* CONFIG_ACPI */
 534
 535         /* scan the system for pnpbios support */
 536         if (!pnpbios_probe_system())
 537                 return -ENODEV;
 538
 539         /* make preparations for bios calls */
 540         pnpbios_calls_init(pnp_bios_install);
 541
 542         /* read the node info */
 543         ret = pnp_bios_dev_node_info(&node_info);
 544         if (ret) {
 545                 printk(KERN_ERR
 546                        "PnPBIOS: Unable to get node info.  Aborting.\n");
 547                 return ret;
 548         }
 549
 550         /* register with the pnp layer */
 551         ret = pnp_register_protocol(&pnpbios_protocol);
 552         if (ret) {
 553                 printk(KERN_ERR
 554                        "PnPBIOS: Unable to register driver.  Aborting.\n");
 555                 return ret;
 556         }
 557
 558         /* start the proc interface */
 559         ret = pnpbios_proc_init();
 560         if (ret)
 561                 printk(KERN_ERR "PnPBIOS: Failed to create proc interface.\n");
 562
 563         /* scan for pnpbios devices */
 564         build_devlist();
 565
 566         pnp_platform_devices = 1;
 567         return 0;
 568 }
 569
 570 fs_initcall(pnpbios_init);
 571
 572 static int __init pnpbios_thread_init(void)
 573 {
 574         struct task_struct *task;
 575
 576         if (pnpbios_disabled)
 577                 return 0;
 578
 579         init_completion(&unload_sem);
 580         task = kthread_run(pnp_dock_thread, NULL, "kpnpbiosd");
 581         if (IS_ERR(task))
 582                 return PTR_ERR(task);
 583
 584         return 0;
 585 }
 586
 587 /* Start the kernel thread later: */
 588 module_init(pnpbios_thread_init);
 589
 590 EXPORT_SYMBOL(pnpbios_protocol);