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/system.h>
  69 #include <asm/byteorder.h>
  70
  71 #include "../base.h"
  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 struct completion unload_sem;
  98
  99 /*
 100  * (Much of this belongs in a shared routine somewhere)
 101  */
 102 static int pnp_dock_event(int dock, struct pnp_docking_station_info *info)
 103 {
 104         char *argv[3], **envp, *buf, *scratch;
 105         int i = 0, value;
 106
 107         if (!(envp = kcalloc(20, sizeof(char *), GFP_KERNEL)))
 108                 return -ENOMEM;
 109         if (!(buf = kzalloc(256, GFP_KERNEL))) {
 110                 kfree(envp);
 111                 return -ENOMEM;
 112         }
 113
 114         /* FIXME: if there are actual users of this, it should be
 115          * integrated into the driver core and use the usual infrastructure
 116          * like sysfs and uevents
 117          */
 118         argv[0] = "/sbin/pnpbios";
 119         argv[1] = "dock";
 120         argv[2] = NULL;
 121
 122         /* minimal command environment */
 123         envp[i++] = "HOME=/";
 124         envp[i++] = "PATH=/sbin:/bin:/usr/sbin:/usr/bin";
 125
 126 #ifdef  DEBUG
 127         /* hint that policy agent should enter no-stdout debug mode */
 128         envp[i++] = "DEBUG=kernel";
 129 #endif
 130         /* extensible set of named bus-specific parameters,
 131          * supporting multiple driver selection algorithms.
 132          */
 133         scratch = buf;
 134
 135         /* action:  add, remove */
 136         envp[i++] = scratch;
 137         scratch += sprintf(scratch, "ACTION=%s", dock ? "add" : "remove") + 1;
 138
 139         /* Report the ident for the dock */
 140         envp[i++] = scratch;
 141         scratch += sprintf(scratch, "DOCK=%x/%x/%x",
 142                            info->location_id, info->serial, info->capabilities);
 143         envp[i] = NULL;
 144
 145         value = call_usermodehelper(argv [0], argv, envp, UMH_WAIT_EXEC);
 146         kfree(buf);
 147         kfree(envp);
 148         return 0;
 149 }
 150
 151 /*
 152  * Poll the PnP docking at regular intervals
 153  */
 154 static int pnp_dock_thread(void *unused)
 155 {
 156         static struct pnp_docking_station_info now;
 157         int docked = -1, d = 0;
 158
 159         set_freezable();
 160         while (1) {
 161                 int status;
 162
 163                 /*
 164                  * Poll every 2 seconds
 165                  */
 166                 msleep_interruptible(2000);
 167
 168                 if (try_to_freeze())
 169                         continue;
 170
 171                 status = pnp_bios_dock_station_info(&now);
 172
 173                 switch (status) {
 174                         /*
 175                          * No dock to manage
 176                          */
 177                 case PNP_FUNCTION_NOT_SUPPORTED:
 178                         complete_and_exit(&unload_sem, 0);
 179                 case PNP_SYSTEM_NOT_DOCKED:
 180                         d = 0;
 181                         break;
 182                 case PNP_SUCCESS:
 183                         d = 1;
 184                         break;
 185                 default:
 186                         pnpbios_print_status("pnp_dock_thread", status);
 187                         continue;
 188                 }
 189                 if (d != docked) {
 190                         if (pnp_dock_event(d, &now) == 0) {
 191                                 docked = d;
 192 #if 0
 193                                 printk(KERN_INFO
 194                                        "PnPBIOS: Docking station %stached\n",
 195                                        docked ? "at" : "de");
 196 #endif
 197                         }
 198                 }
 199         }
 200         complete_and_exit(&unload_sem, 0);
 201 }
 202
 203 #endif                          /* CONFIG_HOTPLUG */
 204
 205 static int pnpbios_get_resources(struct pnp_dev *dev)
 206 {
 207         u8 nodenum = dev->number;
 208         struct pnp_bios_node *node;
 209
 210         if (!pnpbios_is_dynamic(dev))
 211                 return -EPERM;
 212
 213         pnp_dbg(&dev->dev, "get resources\n");
 214         node = kzalloc(node_info.max_node_size, GFP_KERNEL);
 215         if (!node)
 216                 return -1;
 217         if (pnp_bios_get_dev_node(&nodenum, (char)PNPMODE_DYNAMIC, node)) {
 218                 kfree(node);
 219                 return -ENODEV;
 220         }
 221         pnpbios_read_resources_from_node(dev, node);
 222         dev->active = pnp_is_active(dev);
 223         kfree(node);
 224         return 0;
 225 }
 226
 227 static int pnpbios_set_resources(struct pnp_dev *dev)
 228 {
 229         u8 nodenum = dev->number;
 230         struct pnp_bios_node *node;
 231         int ret;
 232
 233         if (!pnpbios_is_dynamic(dev))
 234                 return -EPERM;
 235
 236         pnp_dbg(&dev->dev, "set resources\n");
 237         node = kzalloc(node_info.max_node_size, GFP_KERNEL);
 238         if (!node)
 239                 return -1;
 240         if (pnp_bios_get_dev_node(&nodenum, (char)PNPMODE_DYNAMIC, node)) {
 241                 kfree(node);
 242                 return -ENODEV;
 243         }
 244         if (pnpbios_write_resources_to_node(dev, node) < 0) {
 245                 kfree(node);
 246                 return -1;
 247         }
 248         ret = pnp_bios_set_dev_node(node->handle, (char)PNPMODE_DYNAMIC, node);
 249         kfree(node);
 250         if (ret > 0)
 251                 ret = -1;
 252         return ret;
 253 }
 254
 255 static void pnpbios_zero_data_stream(struct pnp_bios_node *node)
 256 {
 257         unsigned char *p = (char *)node->data;
 258         unsigned char *end = (char *)(node->data + node->size);
 259         unsigned int len;
 260         int i;
 261
 262         while ((char *)p < (char *)end) {
 263                 if (p[0] & 0x80) {      /* large tag */
 264                         len = (p[2] << 8) | p[1];
 265                         p += 3;
 266                 } else {
 267                         if (((p[0] >> 3) & 0x0f) == 0x0f)
 268                                 return;
 269                         len = p[0] & 0x07;
 270                         p += 1;
 271                 }
 272                 for (i = 0; i < len; i++)
 273                         p[i] = 0;
 274                 p += len;
 275         }
 276         printk(KERN_ERR
 277                "PnPBIOS: Resource structure did not contain an end tag.\n");
 278 }
 279
 280 static int pnpbios_disable_resources(struct pnp_dev *dev)
 281 {
 282         struct pnp_bios_node *node;
 283         u8 nodenum = dev->number;
 284         int ret;
 285
 286         if (dev->flags & PNPBIOS_NO_DISABLE || !pnpbios_is_dynamic(dev))
 287                 return -EPERM;
 288
 289         node = kzalloc(node_info.max_node_size, GFP_KERNEL);
 290         if (!node)
 291                 return -ENOMEM;
 292
 293         if (pnp_bios_get_dev_node(&nodenum, (char)PNPMODE_DYNAMIC, node)) {
 294                 kfree(node);
 295                 return -ENODEV;
 296         }
 297         pnpbios_zero_data_stream(node);
 298
 299         ret = pnp_bios_set_dev_node(dev->number, (char)PNPMODE_DYNAMIC, node);
 300         kfree(node);
 301         if (ret > 0)
 302                 ret = -1;
 303         return ret;
 304 }
 305
 306 /* PnP Layer support */
 307
 308 struct pnp_protocol pnpbios_protocol = {
 309         .name = "Plug and Play BIOS",
 310         .get = pnpbios_get_resources,
 311         .set = pnpbios_set_resources,
 312         .disable = pnpbios_disable_resources,
 313 };
 314
 315 static int __init insert_device(struct pnp_bios_node *node)
 316 {
 317         struct list_head *pos;
 318         struct pnp_dev *dev;
 319         char id[8];
 320
 321         /* check if the device is already added */
 322         list_for_each(pos, &pnpbios_protocol.devices) {
 323                 dev = list_entry(pos, struct pnp_dev, protocol_list);
 324                 if (dev->number == node->handle)
 325                         return -1;
 326         }
 327
 328         pnp_eisa_id_to_string(node->eisa_id & PNP_EISA_ID_MASK, id);
 329         dev = pnp_alloc_dev(&pnpbios_protocol, node->handle, id);
 330         if (!dev)
 331                 return -1;
 332
 333         pnpbios_parse_data_stream(dev, node);
 334         dev->active = pnp_is_active(dev);
 335         dev->flags = node->flags;
 336         if (!(dev->flags & PNPBIOS_NO_CONFIG))
 337                 dev->capabilities |= PNP_CONFIGURABLE;
 338         if (!(dev->flags & PNPBIOS_NO_DISABLE) && pnpbios_is_dynamic(dev))
 339                 dev->capabilities |= PNP_DISABLE;
 340         dev->capabilities |= PNP_READ;
 341         if (pnpbios_is_dynamic(dev))
 342                 dev->capabilities |= PNP_WRITE;
 343         if (dev->flags & PNPBIOS_REMOVABLE)
 344                 dev->capabilities |= PNP_REMOVABLE;
 345
 346         /* clear out the damaged flags */
 347         if (!dev->active)
 348                 pnp_init_resources(dev);
 349
 350         pnp_add_device(dev);
 351         pnpbios_interface_attach_device(node);
 352
 353         return 0;
 354 }
 355
 356 static void __init build_devlist(void)
 357 {
 358         u8 nodenum;
 359         unsigned int nodes_got = 0;
 360         unsigned int devs = 0;
 361         struct pnp_bios_node *node;
 362
 363         node = kzalloc(node_info.max_node_size, GFP_KERNEL);
 364         if (!node)
 365                 return;
 366
 367         for (nodenum = 0; nodenum < 0xff;) {
 368                 u8 thisnodenum = nodenum;
 369                 /* eventually we will want to use PNPMODE_STATIC here but for now
 370                  * dynamic will help us catch buggy bioses to add to the blacklist.
 371                  */
 372                 if (!pnpbios_dont_use_current_config) {
 373                         if (pnp_bios_get_dev_node
 374                             (&nodenum, (char)PNPMODE_DYNAMIC, node))
 375                                 break;
 376                 } else {
 377                         if (pnp_bios_get_dev_node
 378                             (&nodenum, (char)PNPMODE_STATIC, node))
 379                                 break;
 380                 }
 381                 nodes_got++;
 382                 if (insert_device(node) == 0)
 383                         devs++;
 384                 if (nodenum <= thisnodenum) {
 385                         printk(KERN_ERR
 386                                "PnPBIOS: build_devlist: Node number 0x%x is out of sequence following node 0x%x. Aborting.\n",
 387                                (unsigned int)nodenum,
 388                                (unsigned int)thisnodenum);
 389                         break;
 390                 }
 391         }
 392         kfree(node);
 393
 394         printk(KERN_INFO
 395                "PnPBIOS: %i node%s reported by PnP BIOS; %i recorded by driver\n",
 396                nodes_got, nodes_got != 1 ? "s" : "", devs);
 397 }
 398
 399 /*
 400  *
 401  * INIT AND EXIT
 402  *
 403  */
 404
 405 static int pnpbios_disabled;
 406 int pnpbios_dont_use_current_config;
 407
 408 static int __init pnpbios_setup(char *str)
 409 {
 410         int invert;
 411
 412         while ((str != NULL) && (*str != '\0')) {
 413                 if (strncmp(str, "off", 3) == 0)
 414                         pnpbios_disabled = 1;
 415                 if (strncmp(str, "on", 2) == 0)
 416                         pnpbios_disabled = 0;
 417                 invert = (strncmp(str, "no-", 3) == 0);
 418                 if (invert)
 419                         str += 3;
 420                 if (strncmp(str, "curr", 4) == 0)
 421                         pnpbios_dont_use_current_config = invert;
 422                 str = strchr(str, ',');
 423                 if (str != NULL)
 424                         str += strspn(str, ", \t");
 425         }
 426
 427         return 1;
 428 }
 429
 430 __setup("pnpbios=", pnpbios_setup);
 431
 432 /* PnP BIOS signature: "$PnP" */
 433 #define PNP_SIGNATURE   (('$' << 0) + ('P' << 8) + ('n' << 16) + ('P' << 24))
 434
 435 static int __init pnpbios_probe_system(void)
 436 {
 437         union pnp_bios_install_struct *check;
 438         u8 sum;
 439         int length, i;
 440
 441         printk(KERN_INFO "PnPBIOS: Scanning system for PnP BIOS support...\n");
 442
 443         /*
 444          * Search the defined area (0xf0000-0xffff0) for a valid PnP BIOS
 445          * structure and, if one is found, sets up the selectors and
 446          * entry points
 447          */
 448         for (check = (union pnp_bios_install_struct *)__va(0xf0000);
 449              check < (union pnp_bios_install_struct *)__va(0xffff0);
 450              check = (void *)check + 16) {
 451                 if (check->fields.signature != PNP_SIGNATURE)
 452                         continue;
 453                 printk(KERN_INFO
 454                        "PnPBIOS: Found PnP BIOS installation structure at 0x%p\n",
 455                        check);
 456                 length = check->fields.length;
 457                 if (!length) {
 458                         printk(KERN_ERR
 459                                "PnPBIOS: installation structure is invalid, skipping\n");
 460                         continue;
 461                 }
 462                 for (sum = 0, i = 0; i < length; i++)
 463                         sum += check->chars[i];
 464                 if (sum) {
 465                         printk(KERN_ERR
 466                                "PnPBIOS: installation structure is corrupted, skipping\n");
 467                         continue;
 468                 }
 469                 if (check->fields.version < 0x10) {
 470                         printk(KERN_WARNING
 471                                "PnPBIOS: PnP BIOS version %d.%d is not supported\n",
 472                                check->fields.version >> 4,
 473                                check->fields.version & 15);
 474                         continue;
 475                 }
 476                 printk(KERN_INFO
 477                        "PnPBIOS: PnP BIOS version %d.%d, entry 0x%x:0x%x, dseg 0x%x\n",
 478                        check->fields.version >> 4, check->fields.version & 15,
 479                        check->fields.pm16cseg, check->fields.pm16offset,
 480                        check->fields.pm16dseg);
 481                 pnp_bios_install = check;
 482                 return 1;
 483         }
 484
 485         printk(KERN_INFO "PnPBIOS: PnP BIOS support was not detected.\n");
 486         return 0;
 487 }
 488
 489 static int __init exploding_pnp_bios(const struct dmi_system_id *d)
 490 {
 491         printk(KERN_WARNING "%s detected. Disabling PnPBIOS\n", d->ident);
 492         return 0;
 493 }
 494
 495 static struct dmi_system_id pnpbios_dmi_table[] __initdata = {
 496         {                       /* PnPBIOS GPF on boot */
 497          .callback = exploding_pnp_bios,
 498          .ident = "Higraded P14H",
 499          .matches = {
 500                      DMI_MATCH(DMI_BIOS_VENDOR, "American Megatrends Inc."),
 501                      DMI_MATCH(DMI_BIOS_VERSION, "07.00T"),
 502                      DMI_MATCH(DMI_SYS_VENDOR, "Higraded"),
 503                      DMI_MATCH(DMI_PRODUCT_NAME, "P14H"),
 504                      },
 505          },
 506         {                       /* PnPBIOS GPF on boot */
 507          .callback = exploding_pnp_bios,
 508          .ident = "ASUS P4P800",
 509          .matches = {
 510                      DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer Inc."),
 511                      DMI_MATCH(DMI_BOARD_NAME, "P4P800"),
 512                      },
 513          },
 514         {}
 515 };
 516
 517 static int __init pnpbios_init(void)
 518 {
 519         int ret;
 520
 521 #if defined(CONFIG_PPC)
 522         if (check_legacy_ioport(PNPBIOS_BASE))
 523                 return -ENODEV;
 524 #endif
 525         if (pnpbios_disabled || dmi_check_system(pnpbios_dmi_table) ||
 526             paravirt_enabled()) {
 527                 printk(KERN_INFO "PnPBIOS: Disabled\n");
 528                 return -ENODEV;
 529         }
 530 #ifdef CONFIG_PNPACPI
 531         if (!acpi_disabled && !pnpacpi_disabled) {
 532                 pnpbios_disabled = 1;
 533                 printk(KERN_INFO "PnPBIOS: Disabled by ACPI PNP\n");
 534                 return -ENODEV;
 535         }
 536 #endif                          /* CONFIG_ACPI */
 537
 538         /* scan the system for pnpbios support */
 539         if (!pnpbios_probe_system())
 540                 return -ENODEV;
 541
 542         /* make preparations for bios calls */
 543         pnpbios_calls_init(pnp_bios_install);
 544
 545         /* read the node info */
 546         ret = pnp_bios_dev_node_info(&node_info);
 547         if (ret) {
 548                 printk(KERN_ERR
 549                        "PnPBIOS: Unable to get node info.  Aborting.\n");
 550                 return ret;
 551         }
 552
 553         /* register with the pnp layer */
 554         ret = pnp_register_protocol(&pnpbios_protocol);
 555         if (ret) {
 556                 printk(KERN_ERR
 557                        "PnPBIOS: Unable to register driver.  Aborting.\n");
 558                 return ret;
 559         }
 560
 561         /* start the proc interface */
 562         ret = pnpbios_proc_init();
 563         if (ret)
 564                 printk(KERN_ERR "PnPBIOS: Failed to create proc interface.\n");
 565
 566         /* scan for pnpbios devices */
 567         build_devlist();
 568
 569         pnp_platform_devices = 1;
 570         return 0;
 571 }
 572
 573 fs_initcall(pnpbios_init);
 574
 575 static int __init pnpbios_thread_init(void)
 576 {
 577 #if defined(CONFIG_PPC)
 578         if (check_legacy_ioport(PNPBIOS_BASE))
 579                 return 0;
 580 #endif
 581         if (pnpbios_disabled)
 582                 return 0;
 583 #ifdef CONFIG_HOTPLUG
 584         {
 585                 struct task_struct *task;
 586                 init_completion(&unload_sem);
 587                 task = kthread_run(pnp_dock_thread, NULL, "kpnpbiosd");
 588                 if (IS_ERR(task))
 589                         return PTR_ERR(task);
 590         }
 591 #endif
 592         return 0;
 593 }
 594
 595 /* Start the kernel thread later: */
 596 module_init(pnpbios_thread_init);
 597
 598 EXPORT_SYMBOL(pnpbios_protocol);