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