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 "../base.h"
  73 #include "pnpbios.h"
  74
  75 /*
  76  *
  77  * PnP BIOS INTERFACE
  78  *
  79  */
  80
  81 static union pnp_bios_install_struct *pnp_bios_install = NULL;
  82
  83 int pnp_bios_present(void)
  84 {
  85         return (pnp_bios_install != NULL);
  86 }
  87
  88 struct pnp_dev_node_info node_info;
  89
  90 /*
  91  *
  92  * DOCKING FUNCTIONS
  93  *
  94  */
  95
  96 #ifdef CONFIG_HOTPLUG
  97
  98 static int unloading = 0;
  99 static struct completion unload_sem;
 100
 101 /*
 102  * (Much of this belongs in a shared routine somewhere)
 103  */
 104 static int pnp_dock_event(int dock, struct pnp_docking_station_info *info)
 105 {
 106         char *argv[3], **envp, *buf, *scratch;
 107         int i = 0, value;
 108
 109         if (!(envp = kcalloc(20, sizeof(char *), GFP_KERNEL)))
 110                 return -ENOMEM;
 111         if (!(buf = kzalloc(256, GFP_KERNEL))) {
 112                 kfree(envp);
 113                 return -ENOMEM;
 114         }
 115
 116         /* FIXME: if there are actual users of this, it should be
 117          * integrated into the driver core and use the usual infrastructure
 118          * like sysfs and uevents
 119          */
 120         argv[0] = "/sbin/pnpbios";
 121         argv[1] = "dock";
 122         argv[2] = NULL;
 123
 124         /* minimal command environment */
 125         envp[i++] = "HOME=/";
 126         envp[i++] = "PATH=/sbin:/bin:/usr/sbin:/usr/bin";
 127
 128 #ifdef  DEBUG
 129         /* hint that policy agent should enter no-stdout debug mode */
 130         envp[i++] = "DEBUG=kernel";
 131 #endif
 132         /* extensible set of named bus-specific parameters,
 133          * supporting multiple driver selection algorithms.
 134          */
 135         scratch = buf;
 136
 137         /* action:  add, remove */
 138         envp[i++] = scratch;
 139         scratch += sprintf(scratch, "ACTION=%s", dock ? "add" : "remove") + 1;
 140
 141         /* Report the ident for the dock */
 142         envp[i++] = scratch;
 143         scratch += sprintf(scratch, "DOCK=%x/%x/%x",
 144                            info->location_id, info->serial, info->capabilities);
 145         envp[i] = NULL;
 146
 147         value = call_usermodehelper(argv [0], argv, envp, UMH_WAIT_EXEC);
 148         kfree(buf);
 149         kfree(envp);
 150         return 0;
 151 }
 152
 153 /*
 154  * Poll the PnP docking at regular intervals
 155  */
 156 static int pnp_dock_thread(void *unused)
 157 {
 158         static struct pnp_docking_station_info now;
 159         int docked = -1, d = 0;
 160
 161         set_freezable();
 162         while (!unloading) {
 163                 int status;
 164
 165                 /*
 166                  * Poll every 2 seconds
 167                  */
 168                 msleep_interruptible(2000);
 169
 170                 if (try_to_freeze())
 171                         continue;
 172
 173                 status = pnp_bios_dock_station_info(&now);
 174
 175                 switch (status) {
 176                         /*
 177                          * No dock to manage
 178                          */
 179                 case PNP_FUNCTION_NOT_SUPPORTED:
 180                         complete_and_exit(&unload_sem, 0);
 181                 case PNP_SYSTEM_NOT_DOCKED:
 182                         d = 0;
 183                         break;
 184                 case PNP_SUCCESS:
 185                         d = 1;
 186                         break;
 187                 default:
 188                         pnpbios_print_status("pnp_dock_thread", status);
 189                         continue;
 190                 }
 191                 if (d != docked) {
 192                         if (pnp_dock_event(d, &now) == 0) {
 193                                 docked = d;
 194 #if 0
 195                                 printk(KERN_INFO
 196                                        "PnPBIOS: Docking station %stached\n",
 197                                        docked ? "at" : "de");
 198 #endif
 199                         }
 200                 }
 201         }
 202         complete_and_exit(&unload_sem, 0);
 203 }
 204
 205 #endif                          /* CONFIG_HOTPLUG */
 206
 207 static int pnpbios_get_resources(struct pnp_dev *dev,
 208                                  struct pnp_resource_table *res)
 209 {
 210         u8 nodenum = dev->number;
 211         struct pnp_bios_node *node;
 212
 213         if (!pnpbios_is_dynamic(dev))
 214                 return -EPERM;
 215
 216         node = kzalloc(node_info.max_node_size, GFP_KERNEL);
 217         if (!node)
 218                 return -1;
 219         if (pnp_bios_get_dev_node(&nodenum, (char)PNPMODE_DYNAMIC, node)) {
 220                 kfree(node);
 221                 return -ENODEV;
 222         }
 223         pnpbios_read_resources_from_node(res, node);
 224         dev->active = pnp_is_active(dev);
 225         kfree(node);
 226         return 0;
 227 }
 228
 229 static int pnpbios_set_resources(struct pnp_dev *dev,
 230                                  struct pnp_resource_table *res)
 231 {
 232         u8 nodenum = dev->number;
 233         struct pnp_bios_node *node;
 234         int ret;
 235
 236         if (!pnpbios_is_dynamic(dev))
 237                 return -EPERM;
 238
 239         node = kzalloc(node_info.max_node_size, GFP_KERNEL);
 240         if (!node)
 241                 return -1;
 242         if (pnp_bios_get_dev_node(&nodenum, (char)PNPMODE_DYNAMIC, node)) {
 243                 kfree(node);
 244                 return -ENODEV;
 245         }
 246         if (pnpbios_write_resources_to_node(res, node) < 0) {
 247                 kfree(node);
 248                 return -1;
 249         }
 250         ret = pnp_bios_set_dev_node(node->handle, (char)PNPMODE_DYNAMIC, node);
 251         kfree(node);
 252         if (ret > 0)
 253                 ret = -1;
 254         return ret;
 255 }
 256
 257 static void pnpbios_zero_data_stream(struct pnp_bios_node *node)
 258 {
 259         unsigned char *p = (char *)node->data;
 260         unsigned char *end = (char *)(node->data + node->size);
 261         unsigned int len;
 262         int i;
 263
 264         while ((char *)p < (char *)end) {
 265                 if (p[0] & 0x80) {      /* large tag */
 266                         len = (p[2] << 8) | p[1];
 267                         p += 3;
 268                 } else {
 269                         if (((p[0] >> 3) & 0x0f) == 0x0f)
 270                                 return;
 271                         len = p[0] & 0x07;
 272                         p += 1;
 273                 }
 274                 for (i = 0; i < len; i++)
 275                         p[i] = 0;
 276                 p += len;
 277         }
 278         printk(KERN_ERR
 279                "PnPBIOS: Resource structure did not contain an end tag.\n");
 280 }
 281
 282 static int pnpbios_disable_resources(struct pnp_dev *dev)
 283 {
 284         struct pnp_bios_node *node;
 285         u8 nodenum = dev->number;
 286         int ret;
 287
 288         if (dev->flags & PNPBIOS_NO_DISABLE || !pnpbios_is_dynamic(dev))
 289                 return -EPERM;
 290
 291         node = kzalloc(node_info.max_node_size, GFP_KERNEL);
 292         if (!node)
 293                 return -ENOMEM;
 294
 295         if (pnp_bios_get_dev_node(&nodenum, (char)PNPMODE_DYNAMIC, node)) {
 296                 kfree(node);
 297                 return -ENODEV;
 298         }
 299         pnpbios_zero_data_stream(node);
 300
 301         ret = pnp_bios_set_dev_node(dev->number, (char)PNPMODE_DYNAMIC, node);
 302         kfree(node);
 303         if (ret > 0)
 304                 ret = -1;
 305         return ret;
 306 }
 307
 308 /* PnP Layer support */
 309
 310 struct pnp_protocol pnpbios_protocol = {
 311         .name = "Plug and Play BIOS",
 312         .get = pnpbios_get_resources,
 313         .set = pnpbios_set_resources,
 314         .disable = pnpbios_disable_resources,
 315 };
 316
 317 static int __init insert_device(struct pnp_bios_node *node)
 318 {
 319         struct list_head *pos;
 320         struct pnp_dev *dev;
 321         struct pnp_id *dev_id;
 322         char id[8];
 323
 324         /* check if the device is already added */
 325         list_for_each(pos, &pnpbios_protocol.devices) {
 326                 dev = list_entry(pos, struct pnp_dev, protocol_list);
 327                 if (dev->number == node->handle)
 328                         return -1;
 329         }
 330
 331         dev = kzalloc(sizeof(struct pnp_dev), GFP_KERNEL);
 332         if (!dev)
 333                 return -1;
 334
 335         pnpid32_to_pnpid(node->eisa_id, id);
 336         dev_id = pnp_add_id(dev, id);
 337         if (!dev_id) {
 338                 kfree(dev);
 339                 return -1;
 340         }
 341
 342         dev->number = node->handle;
 343         pnpbios_parse_data_stream(dev, node);
 344         dev->active = pnp_is_active(dev);
 345         dev->flags = node->flags;
 346         if (!(dev->flags & PNPBIOS_NO_CONFIG))
 347                 dev->capabilities |= PNP_CONFIGURABLE;
 348         if (!(dev->flags & PNPBIOS_NO_DISABLE) && pnpbios_is_dynamic(dev))
 349                 dev->capabilities |= PNP_DISABLE;
 350         dev->capabilities |= PNP_READ;
 351         if (pnpbios_is_dynamic(dev))
 352                 dev->capabilities |= PNP_WRITE;
 353         if (dev->flags & PNPBIOS_REMOVABLE)
 354                 dev->capabilities |= PNP_REMOVABLE;
 355         dev->protocol = &pnpbios_protocol;
 356
 357         /* clear out the damaged flags */
 358         if (!dev->active)
 359                 pnp_init_resource_table(&dev->res);
 360
 361         pnp_add_device(dev);
 362         pnpbios_interface_attach_device(node);
 363
 364         return 0;
 365 }
 366
 367 static void __init build_devlist(void)
 368 {
 369         u8 nodenum;
 370         unsigned int nodes_got = 0;
 371         unsigned int devs = 0;
 372         struct pnp_bios_node *node;
 373
 374         node = kzalloc(node_info.max_node_size, GFP_KERNEL);
 375         if (!node)
 376                 return;
 377
 378         for (nodenum = 0; nodenum < 0xff;) {
 379                 u8 thisnodenum = nodenum;
 380                 /* eventually we will want to use PNPMODE_STATIC here but for now
 381                  * dynamic will help us catch buggy bioses to add to the blacklist.
 382                  */
 383                 if (!pnpbios_dont_use_current_config) {
 384                         if (pnp_bios_get_dev_node
 385                             (&nodenum, (char)PNPMODE_DYNAMIC, node))
 386                                 break;
 387                 } else {
 388                         if (pnp_bios_get_dev_node
 389                             (&nodenum, (char)PNPMODE_STATIC, node))
 390                                 break;
 391                 }
 392                 nodes_got++;
 393                 if (insert_device(node) == 0)
 394                         devs++;
 395                 if (nodenum <= thisnodenum) {
 396                         printk(KERN_ERR
 397                                "PnPBIOS: build_devlist: Node number 0x%x is out of sequence following node 0x%x. Aborting.\n",
 398                                (unsigned int)nodenum,
 399                                (unsigned int)thisnodenum);
 400                         break;
 401                 }
 402         }
 403         kfree(node);
 404
 405         printk(KERN_INFO
 406                "PnPBIOS: %i node%s reported by PnP BIOS; %i recorded by driver\n",
 407                nodes_got, nodes_got != 1 ? "s" : "", devs);
 408 }
 409
 410 /*
 411  *
 412  * INIT AND EXIT
 413  *
 414  */
 415
 416 static int pnpbios_disabled;
 417 int pnpbios_dont_use_current_config;
 418
 419 static int __init pnpbios_setup(char *str)
 420 {
 421         int invert;
 422
 423         while ((str != NULL) && (*str != '\0')) {
 424                 if (strncmp(str, "off", 3) == 0)
 425                         pnpbios_disabled = 1;
 426                 if (strncmp(str, "on", 2) == 0)
 427                         pnpbios_disabled = 0;
 428                 invert = (strncmp(str, "no-", 3) == 0);
 429                 if (invert)
 430                         str += 3;
 431                 if (strncmp(str, "curr", 4) == 0)
 432                         pnpbios_dont_use_current_config = invert;
 433                 str = strchr(str, ',');
 434                 if (str != NULL)
 435                         str += strspn(str, ", \t");
 436         }
 437
 438         return 1;
 439 }
 440
 441 __setup("pnpbios=", pnpbios_setup);
 442
 443 /* PnP BIOS signature: "$PnP" */
 444 #define PNP_SIGNATURE   (('$' << 0) + ('P' << 8) + ('n' << 16) + ('P' << 24))
 445
 446 static int __init pnpbios_probe_system(void)
 447 {
 448         union pnp_bios_install_struct *check;
 449         u8 sum;
 450         int length, i;
 451
 452         printk(KERN_INFO "PnPBIOS: Scanning system for PnP BIOS support...\n");
 453
 454         /*
 455          * Search the defined area (0xf0000-0xffff0) for a valid PnP BIOS
 456          * structure and, if one is found, sets up the selectors and
 457          * entry points
 458          */
 459         for (check = (union pnp_bios_install_struct *)__va(0xf0000);
 460              check < (union pnp_bios_install_struct *)__va(0xffff0);
 461              check = (void *)check + 16) {
 462                 if (check->fields.signature != PNP_SIGNATURE)
 463                         continue;
 464                 printk(KERN_INFO
 465                        "PnPBIOS: Found PnP BIOS installation structure at 0x%p\n",
 466                        check);
 467                 length = check->fields.length;
 468                 if (!length) {
 469                         printk(KERN_ERR
 470                                "PnPBIOS: installation structure is invalid, skipping\n");
 471                         continue;
 472                 }
 473                 for (sum = 0, i = 0; i < length; i++)
 474                         sum += check->chars[i];
 475                 if (sum) {
 476                         printk(KERN_ERR
 477                                "PnPBIOS: installation structure is corrupted, skipping\n");
 478                         continue;
 479                 }
 480                 if (check->fields.version < 0x10) {
 481                         printk(KERN_WARNING
 482                                "PnPBIOS: PnP BIOS version %d.%d is not supported\n",
 483                                check->fields.version >> 4,
 484                                check->fields.version & 15);
 485                         continue;
 486                 }
 487                 printk(KERN_INFO
 488                        "PnPBIOS: PnP BIOS version %d.%d, entry 0x%x:0x%x, dseg 0x%x\n",
 489                        check->fields.version >> 4, check->fields.version & 15,
 490                        check->fields.pm16cseg, check->fields.pm16offset,
 491                        check->fields.pm16dseg);
 492                 pnp_bios_install = check;
 493                 return 1;
 494         }
 495
 496         printk(KERN_INFO "PnPBIOS: PnP BIOS support was not detected.\n");
 497         return 0;
 498 }
 499
 500 static int __init exploding_pnp_bios(const struct dmi_system_id *d)
 501 {
 502         printk(KERN_WARNING "%s detected. Disabling PnPBIOS\n", d->ident);
 503         return 0;
 504 }
 505
 506 static struct dmi_system_id pnpbios_dmi_table[] __initdata = {
 507         {                       /* PnPBIOS GPF on boot */
 508          .callback = exploding_pnp_bios,
 509          .ident = "Higraded P14H",
 510          .matches = {
 511                      DMI_MATCH(DMI_BIOS_VENDOR, "American Megatrends Inc."),
 512                      DMI_MATCH(DMI_BIOS_VERSION, "07.00T"),
 513                      DMI_MATCH(DMI_SYS_VENDOR, "Higraded"),
 514                      DMI_MATCH(DMI_PRODUCT_NAME, "P14H"),
 515                      },
 516          },
 517         {                       /* PnPBIOS GPF on boot */
 518          .callback = exploding_pnp_bios,
 519          .ident = "ASUS P4P800",
 520          .matches = {
 521                      DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer Inc."),
 522                      DMI_MATCH(DMI_BOARD_NAME, "P4P800"),
 523                      },
 524          },
 525         {}
 526 };
 527
 528 static int __init pnpbios_init(void)
 529 {
 530         int ret;
 531
 532 #if defined(CONFIG_PPC_MERGE)
 533         if (check_legacy_ioport(PNPBIOS_BASE))
 534                 return -ENODEV;
 535 #endif
 536         if (pnpbios_disabled || dmi_check_system(pnpbios_dmi_table) ||
 537             paravirt_enabled()) {
 538                 printk(KERN_INFO "PnPBIOS: Disabled\n");
 539                 return -ENODEV;
 540         }
 541 #ifdef CONFIG_PNPACPI
 542         if (!acpi_disabled && !pnpacpi_disabled) {
 543                 pnpbios_disabled = 1;
 544                 printk(KERN_INFO "PnPBIOS: Disabled by ACPI PNP\n");
 545                 return -ENODEV;
 546         }
 547 #endif                          /* CONFIG_ACPI */
 548
 549         /* scan the system for pnpbios support */
 550         if (!pnpbios_probe_system())
 551                 return -ENODEV;
 552
 553         /* make preparations for bios calls */
 554         pnpbios_calls_init(pnp_bios_install);
 555
 556         /* read the node info */
 557         ret = pnp_bios_dev_node_info(&node_info);
 558         if (ret) {
 559                 printk(KERN_ERR
 560                        "PnPBIOS: Unable to get node info.  Aborting.\n");
 561                 return ret;
 562         }
 563
 564         /* register with the pnp layer */
 565         ret = pnp_register_protocol(&pnpbios_protocol);
 566         if (ret) {
 567                 printk(KERN_ERR
 568                        "PnPBIOS: Unable to register driver.  Aborting.\n");
 569                 return ret;
 570         }
 571
 572         /* start the proc interface */
 573         ret = pnpbios_proc_init();
 574         if (ret)
 575                 printk(KERN_ERR "PnPBIOS: Failed to create proc interface.\n");
 576
 577         /* scan for pnpbios devices */
 578         build_devlist();
 579
 580         pnp_platform_devices = 1;
 581         return 0;
 582 }
 583
 584 subsys_initcall(pnpbios_init);
 585
 586 static int __init pnpbios_thread_init(void)
 587 {
 588         struct task_struct *task;
 589
 590 #if defined(CONFIG_PPC_MERGE)
 591         if (check_legacy_ioport(PNPBIOS_BASE))
 592                 return 0;
 593 #endif
 594         if (pnpbios_disabled)
 595                 return 0;
 596 #ifdef CONFIG_HOTPLUG
 597         init_completion(&unload_sem);
 598         task = kthread_run(pnp_dock_thread, NULL, "kpnpbiosd");
 599         if (!IS_ERR(task))
 600                 unloading = 0;
 601 #endif
 602         return 0;
 603 }
 604
 605 /* Start the kernel thread later: */
 606 module_init(pnpbios_thread_init);
 607
 608 EXPORT_SYMBOL(pnpbios_protocol);