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 #ifdef CONFIG_HOTPLUG
  95
  96 static struct completion unload_sem;
  97
  98 /*
  99  * (Much of this belongs in a shared routine somewhere)
 100  */
 101 static int pnp_dock_event(int dock, struct pnp_docking_station_info *info)
 102 {
 103         char *argv[3], **envp, *buf, *scratch;
 104         int i = 0, value;
 105
 106         if (!(envp = kcalloc(20, sizeof(char *), GFP_KERNEL)))
 107                 return -ENOMEM;
 108         if (!(buf = kzalloc(256, GFP_KERNEL))) {
 109                 kfree(envp);
 110                 return -ENOMEM;
 111         }
 112
 113         /* FIXME: if there are actual users of this, it should be
 114          * integrated into the driver core and use the usual infrastructure
 115          * like sysfs and uevents
 116          */
 117         argv[0] = "/sbin/pnpbios";
 118         argv[1] = "dock";
 119         argv[2] = NULL;
 120
 121         /* minimal command environment */
 122         envp[i++] = "HOME=/";
 123         envp[i++] = "PATH=/sbin:/bin:/usr/sbin:/usr/bin";
 124
 125 #ifdef  DEBUG
 126         /* hint that policy agent should enter no-stdout debug mode */
 127         envp[i++] = "DEBUG=kernel";
 128 #endif
 129         /* extensible set of named bus-specific parameters,
 130          * supporting multiple driver selection algorithms.
 131          */
 132         scratch = buf;
 133
 134         /* action:  add, remove */
 135         envp[i++] = scratch;
 136         scratch += sprintf(scratch, "ACTION=%s", dock ? "add" : "remove") + 1;
 137
 138         /* Report the ident for the dock */
 139         envp[i++] = scratch;
 140         scratch += sprintf(scratch, "DOCK=%x/%x/%x",
 141                            info->location_id, info->serial, info->capabilities);
 142         envp[i] = NULL;
 143
 144         value = call_usermodehelper(argv [0], argv, envp, UMH_WAIT_EXEC);
 145         kfree(buf);
 146         kfree(envp);
 147         return 0;
 148 }
 149
 150 /*
 151  * Poll the PnP docking at regular intervals
 152  */
 153 static int pnp_dock_thread(void *unused)
 154 {
 155         static struct pnp_docking_station_info now;
 156         int docked = -1, d = 0;
 157
 158         set_freezable();
 159         while (1) {
 160                 int status;
 161
 162                 /*
 163                  * Poll every 2 seconds
 164                  */
 165                 msleep_interruptible(2000);
 166
 167                 if (try_to_freeze())
 168                         continue;
 169
 170                 status = pnp_bios_dock_station_info(&now);
 171
 172                 switch (status) {
 173                         /*
 174                          * No dock to manage
 175                          */
 176                 case PNP_FUNCTION_NOT_SUPPORTED:
 177                         complete_and_exit(&unload_sem, 0);
 178                 case PNP_SYSTEM_NOT_DOCKED:
 179                         d = 0;
 180                         break;
 181                 case PNP_SUCCESS:
 182                         d = 1;
 183                         break;
 184                 default:
 185                         pnpbios_print_status("pnp_dock_thread", status);
 186                         continue;
 187                 }
 188                 if (d != docked) {
 189                         if (pnp_dock_event(d, &now) == 0) {
 190                                 docked = d;
 191 #if 0
 192                                 printk(KERN_INFO
 193                                        "PnPBIOS: Docking station %stached\n",
 194                                        docked ? "at" : "de");
 195 #endif
 196                         }
 197                 }
 198         }
 199         complete_and_exit(&unload_sem, 0);
 200 }
 201
 202 #endif                          /* CONFIG_HOTPLUG */
 203
 204 static int pnpbios_get_resources(struct pnp_dev *dev)
 205 {
 206         u8 nodenum = dev->number;
 207         struct pnp_bios_node *node;
 208
 209         if (!pnpbios_is_dynamic(dev))
 210                 return -EPERM;
 211
 212         pnp_dbg(&dev->dev, "get resources\n");
 213         node = kzalloc(node_info.max_node_size, GFP_KERNEL);
 214         if (!node)
 215                 return -1;
 216         if (pnp_bios_get_dev_node(&nodenum, (char)PNPMODE_DYNAMIC, node)) {
 217                 kfree(node);
 218                 return -ENODEV;
 219         }
 220         pnpbios_read_resources_from_node(dev, node);
 221         dev->active = pnp_is_active(dev);
 222         kfree(node);
 223         return 0;
 224 }
 225
 226 static int pnpbios_set_resources(struct pnp_dev *dev)
 227 {
 228         u8 nodenum = dev->number;
 229         struct pnp_bios_node *node;
 230         int ret;
 231
 232         if (!pnpbios_is_dynamic(dev))
 233                 return -EPERM;
 234
 235         pnp_dbg(&dev->dev, "set resources\n");
 236         node = kzalloc(node_info.max_node_size, GFP_KERNEL);
 237         if (!node)
 238                 return -1;
 239         if (pnp_bios_get_dev_node(&nodenum, (char)PNPMODE_DYNAMIC, node)) {
 240                 kfree(node);
 241                 return -ENODEV;
 242         }
 243         if (pnpbios_write_resources_to_node(dev, node) < 0) {
 244                 kfree(node);
 245                 return -1;
 246         }
 247         ret = pnp_bios_set_dev_node(node->handle, (char)PNPMODE_DYNAMIC, node);
 248         kfree(node);
 249         if (ret > 0)
 250                 ret = -1;
 251         return ret;
 252 }
 253
 254 static void pnpbios_zero_data_stream(struct pnp_bios_node *node)
 255 {
 256         unsigned char *p = (char *)node->data;
 257         unsigned char *end = (char *)(node->data + node->size);
 258         unsigned int len;
 259         int i;
 260
 261         while ((char *)p < (char *)end) {
 262                 if (p[0] & 0x80) {      /* large tag */
 263                         len = (p[2] << 8) | p[1];
 264                         p += 3;
 265                 } else {
 266                         if (((p[0] >> 3) & 0x0f) == 0x0f)
 267                                 return;
 268                         len = p[0] & 0x07;
 269                         p += 1;
 270                 }
 271                 for (i = 0; i < len; i++)
 272                         p[i] = 0;
 273                 p += len;
 274         }
 275         printk(KERN_ERR
 276                "PnPBIOS: Resource structure did not contain an end tag.\n");
 277 }
 278
 279 static int pnpbios_disable_resources(struct pnp_dev *dev)
 280 {
 281         struct pnp_bios_node *node;
 282         u8 nodenum = dev->number;
 283         int ret;
 284
 285         if (dev->flags & PNPBIOS_NO_DISABLE || !pnpbios_is_dynamic(dev))
 286                 return -EPERM;
 287
 288         node = kzalloc(node_info.max_node_size, GFP_KERNEL);
 289         if (!node)
 290                 return -ENOMEM;
 291
 292         if (pnp_bios_get_dev_node(&nodenum, (char)PNPMODE_DYNAMIC, node)) {
 293                 kfree(node);
 294                 return -ENODEV;
 295         }
 296         pnpbios_zero_data_stream(node);
 297
 298         ret = pnp_bios_set_dev_node(dev->number, (char)PNPMODE_DYNAMIC, node);
 299         kfree(node);
 300         if (ret > 0)
 301                 ret = -1;
 302         return ret;
 303 }
 304
 305 /* PnP Layer support */
 306
 307 struct pnp_protocol pnpbios_protocol = {
 308         .name = "Plug and Play BIOS",
 309         .get = pnpbios_get_resources,
 310         .set = pnpbios_set_resources,
 311         .disable = pnpbios_disable_resources,
 312 };
 313
 314 static int __init insert_device(struct pnp_bios_node *node)
 315 {
 316         struct list_head *pos;
 317         struct pnp_dev *dev;
 318         char id[8];
 319
 320         /* check if the device is already added */
 321         list_for_each(pos, &pnpbios_protocol.devices) {
 322                 dev = list_entry(pos, struct pnp_dev, protocol_list);
 323                 if (dev->number == node->handle)
 324                         return -1;
 325         }
 326
 327         pnp_eisa_id_to_string(node->eisa_id & PNP_EISA_ID_MASK, id);
 328         dev = pnp_alloc_dev(&pnpbios_protocol, node->handle, id);
 329         if (!dev)
 330                 return -1;
 331
 332         pnpbios_parse_data_stream(dev, node);
 333         dev->active = pnp_is_active(dev);
 334         dev->flags = node->flags;
 335         if (!(dev->flags & PNPBIOS_NO_CONFIG))
 336                 dev->capabilities |= PNP_CONFIGURABLE;
 337         if (!(dev->flags & PNPBIOS_NO_DISABLE) && pnpbios_is_dynamic(dev))
 338                 dev->capabilities |= PNP_DISABLE;
 339         dev->capabilities |= PNP_READ;
 340         if (pnpbios_is_dynamic(dev))
 341                 dev->capabilities |= PNP_WRITE;
 342         if (dev->flags & PNPBIOS_REMOVABLE)
 343                 dev->capabilities |= PNP_REMOVABLE;
 344
 345         /* clear out the damaged flags */
 346         if (!dev->active)
 347                 pnp_init_resources(dev);
 348
 349         pnp_add_device(dev);
 350         pnpbios_interface_attach_device(node);
 351
 352         return 0;
 353 }
 354
 355 static void __init build_devlist(void)
 356 {
 357         u8 nodenum;
 358         unsigned int nodes_got = 0;
 359         unsigned int devs = 0;
 360         struct pnp_bios_node *node;
 361
 362         node = kzalloc(node_info.max_node_size, GFP_KERNEL);
 363         if (!node)
 364                 return;
 365
 366         for (nodenum = 0; nodenum < 0xff;) {
 367                 u8 thisnodenum = nodenum;
 368                 /* eventually we will want to use PNPMODE_STATIC here but for now
 369                  * dynamic will help us catch buggy bioses to add to the blacklist.
 370                  */
 371                 if (!pnpbios_dont_use_current_config) {
 372                         if (pnp_bios_get_dev_node
 373                             (&nodenum, (char)PNPMODE_DYNAMIC, node))
 374                                 break;
 375                 } else {
 376                         if (pnp_bios_get_dev_node
 377                             (&nodenum, (char)PNPMODE_STATIC, node))
 378                                 break;
 379                 }
 380                 nodes_got++;
 381                 if (insert_device(node) == 0)
 382                         devs++;
 383                 if (nodenum <= thisnodenum) {
 384                         printk(KERN_ERR
 385                                "PnPBIOS: build_devlist: Node number 0x%x is out of sequence following node 0x%x. Aborting.\n",
 386                                (unsigned int)nodenum,
 387                                (unsigned int)thisnodenum);
 388                         break;
 389                 }
 390         }
 391         kfree(node);
 392
 393         printk(KERN_INFO
 394                "PnPBIOS: %i node%s reported by PnP BIOS; %i recorded by driver\n",
 395                nodes_got, nodes_got != 1 ? "s" : "", devs);
 396 }
 397
 398 /*
 399  *
 400  * INIT AND EXIT
 401  *
 402  */
 403
 404 static int pnpbios_disabled;
 405 int pnpbios_dont_use_current_config;
 406
 407 static int __init pnpbios_setup(char *str)
 408 {
 409         int invert;
 410
 411         while ((str != NULL) && (*str != '\0')) {
 412                 if (strncmp(str, "off", 3) == 0)
 413                         pnpbios_disabled = 1;
 414                 if (strncmp(str, "on", 2) == 0)
 415                         pnpbios_disabled = 0;
 416                 invert = (strncmp(str, "no-", 3) == 0);
 417                 if (invert)
 418                         str += 3;
 419                 if (strncmp(str, "curr", 4) == 0)
 420                         pnpbios_dont_use_current_config = invert;
 421                 str = strchr(str, ',');
 422                 if (str != NULL)
 423                         str += strspn(str, ", \t");
 424         }
 425
 426         return 1;
 427 }
 428
 429 __setup("pnpbios=", pnpbios_setup);
 430
 431 /* PnP BIOS signature: "$PnP" */
 432 #define PNP_SIGNATURE   (('$' << 0) + ('P' << 8) + ('n' << 16) + ('P' << 24))
 433
 434 static int __init pnpbios_probe_system(void)
 435 {
 436         union pnp_bios_install_struct *check;
 437         u8 sum;
 438         int length, i;
 439
 440         printk(KERN_INFO "PnPBIOS: Scanning system for PnP BIOS support...\n");
 441
 442         /*
 443          * Search the defined area (0xf0000-0xffff0) for a valid PnP BIOS
 444          * structure and, if one is found, sets up the selectors and
 445          * entry points
 446          */
 447         for (check = (union pnp_bios_install_struct *)__va(0xf0000);
 448              check < (union pnp_bios_install_struct *)__va(0xffff0);
 449              check = (void *)check + 16) {
 450                 if (check->fields.signature != PNP_SIGNATURE)
 451                         continue;
 452                 printk(KERN_INFO
 453                        "PnPBIOS: Found PnP BIOS installation structure at 0x%p\n",
 454                        check);
 455                 length = check->fields.length;
 456                 if (!length) {
 457                         printk(KERN_ERR
 458                                "PnPBIOS: installation structure is invalid, skipping\n");
 459                         continue;
 460                 }
 461                 for (sum = 0, i = 0; i < length; i++)
 462                         sum += check->chars[i];
 463                 if (sum) {
 464                         printk(KERN_ERR
 465                                "PnPBIOS: installation structure is corrupted, skipping\n");
 466                         continue;
 467                 }
 468                 if (check->fields.version < 0x10) {
 469                         printk(KERN_WARNING
 470                                "PnPBIOS: PnP BIOS version %d.%d is not supported\n",
 471                                check->fields.version >> 4,
 472                                check->fields.version & 15);
 473                         continue;
 474                 }
 475                 printk(KERN_INFO
 476                        "PnPBIOS: PnP BIOS version %d.%d, entry 0x%x:0x%x, dseg 0x%x\n",
 477                        check->fields.version >> 4, check->fields.version & 15,
 478                        check->fields.pm16cseg, check->fields.pm16offset,
 479                        check->fields.pm16dseg);
 480                 pnp_bios_install = check;
 481                 return 1;
 482         }
 483
 484         printk(KERN_INFO "PnPBIOS: PnP BIOS support was not detected.\n");
 485         return 0;
 486 }
 487
 488 static int __init exploding_pnp_bios(const struct dmi_system_id *d)
 489 {
 490         printk(KERN_WARNING "%s detected. Disabling PnPBIOS\n", d->ident);
 491         return 0;
 492 }
 493
 494 static struct dmi_system_id pnpbios_dmi_table[] __initdata = {
 495         {                       /* PnPBIOS GPF on boot */
 496          .callback = exploding_pnp_bios,
 497          .ident = "Higraded P14H",
 498          .matches = {
 499                      DMI_MATCH(DMI_BIOS_VENDOR, "American Megatrends Inc."),
 500                      DMI_MATCH(DMI_BIOS_VERSION, "07.00T"),
 501                      DMI_MATCH(DMI_SYS_VENDOR, "Higraded"),
 502                      DMI_MATCH(DMI_PRODUCT_NAME, "P14H"),
 503                      },
 504          },
 505         {                       /* PnPBIOS GPF on boot */
 506          .callback = exploding_pnp_bios,
 507          .ident = "ASUS P4P800",
 508          .matches = {
 509                      DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer Inc."),
 510                      DMI_MATCH(DMI_BOARD_NAME, "P4P800"),
 511                      },
 512          },
 513         {}
 514 };
 515
 516 static int __init pnpbios_init(void)
 517 {
 518         int ret;
 519
 520 #if defined(CONFIG_PPC)
 521         if (check_legacy_ioport(PNPBIOS_BASE))
 522                 return -ENODEV;
 523 #endif
 524         if (pnpbios_disabled || dmi_check_system(pnpbios_dmi_table) ||
 525             paravirt_enabled()) {
 526                 printk(KERN_INFO "PnPBIOS: Disabled\n");
 527                 return -ENODEV;
 528         }
 529 #ifdef CONFIG_PNPACPI
 530         if (!acpi_disabled && !pnpacpi_disabled) {
 531                 pnpbios_disabled = 1;
 532                 printk(KERN_INFO "PnPBIOS: Disabled by ACPI PNP\n");
 533                 return -ENODEV;
 534         }
 535 #endif                          /* CONFIG_ACPI */
 536
 537         /* scan the system for pnpbios support */
 538         if (!pnpbios_probe_system())
 539                 return -ENODEV;
 540
 541         /* make preparations for bios calls */
 542         pnpbios_calls_init(pnp_bios_install);
 543
 544         /* read the node info */
 545         ret = pnp_bios_dev_node_info(&node_info);
 546         if (ret) {
 547                 printk(KERN_ERR
 548                        "PnPBIOS: Unable to get node info.  Aborting.\n");
 549                 return ret;
 550         }
 551
 552         /* register with the pnp layer */
 553         ret = pnp_register_protocol(&pnpbios_protocol);
 554         if (ret) {
 555                 printk(KERN_ERR
 556                        "PnPBIOS: Unable to register driver.  Aborting.\n");
 557                 return ret;
 558         }
 559
 560         /* start the proc interface */
 561         ret = pnpbios_proc_init();
 562         if (ret)
 563                 printk(KERN_ERR "PnPBIOS: Failed to create proc interface.\n");
 564
 565         /* scan for pnpbios devices */
 566         build_devlist();
 567
 568         pnp_platform_devices = 1;
 569         return 0;
 570 }
 571
 572 fs_initcall(pnpbios_init);
 573
 574 static int __init pnpbios_thread_init(void)
 575 {
 576 #if defined(CONFIG_PPC)
 577         if (check_legacy_ioport(PNPBIOS_BASE))
 578                 return 0;
 579 #endif
 580         if (pnpbios_disabled)
 581                 return 0;
 582 #ifdef CONFIG_HOTPLUG
 583         {
 584                 struct task_struct *task;
 585                 init_completion(&unload_sem);
 586                 task = kthread_run(pnp_dock_thread, NULL, "kpnpbiosd");
 587                 if (IS_ERR(task))
 588                         return PTR_ERR(task);
 589         }
 590 #endif
 591         return 0;
 592 }
 593
 594 /* Start the kernel thread later: */
 595 module_init(pnpbios_thread_init);
 596
 597 EXPORT_SYMBOL(pnpbios_protocol);