linux/drivers/pnp/pnpbios/core.c
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   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
  79static union pnp_bios_install_struct *pnp_bios_install = NULL;
  80
  81int pnp_bios_present(void)
  82{
  83        return (pnp_bios_install != NULL);
  84}
  85
  86struct pnp_dev_node_info node_info;
  87
  88/*
  89 *
  90 * DOCKING FUNCTIONS
  91 *
  92 */
  93
  94static struct completion unload_sem;
  95
  96/*
  97 * (Much of this belongs in a shared routine somewhere)
  98 */
  99static 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 */
 151static 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
 200static 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
 222static 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
 250static 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
 275static 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
 303struct 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
 310static 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
 316        /* check if the device is already added */
 317        list_for_each(pos, &pnpbios_protocol.devices) {
 318                dev = list_entry(pos, struct pnp_dev, protocol_list);
 319                if (dev->number == node->handle)
 320                        return -1;
 321        }
 322
 323        pnp_eisa_id_to_string(node->eisa_id & PNP_EISA_ID_MASK, id);
 324        dev = pnp_alloc_dev(&pnpbios_protocol, node->handle, id);
 325        if (!dev)
 326                return -1;
 327
 328        pnpbios_parse_data_stream(dev, node);
 329        dev->active = pnp_is_active(dev);
 330        dev->flags = node->flags;
 331        if (!(dev->flags & PNPBIOS_NO_CONFIG))
 332                dev->capabilities |= PNP_CONFIGURABLE;
 333        if (!(dev->flags & PNPBIOS_NO_DISABLE) && pnpbios_is_dynamic(dev))
 334                dev->capabilities |= PNP_DISABLE;
 335        dev->capabilities |= PNP_READ;
 336        if (pnpbios_is_dynamic(dev))
 337                dev->capabilities |= PNP_WRITE;
 338        if (dev->flags & PNPBIOS_REMOVABLE)
 339                dev->capabilities |= PNP_REMOVABLE;
 340
 341        /* clear out the damaged flags */
 342        if (!dev->active)
 343                pnp_init_resources(dev);
 344
 345        pnp_add_device(dev);
 346        pnpbios_interface_attach_device(node);
 347
 348        return 0;
 349}
 350
 351static void __init build_devlist(void)
 352{
 353        u8 nodenum;
 354        unsigned int nodes_got = 0;
 355        unsigned int devs = 0;
 356        struct pnp_bios_node *node;
 357
 358        node = kzalloc(node_info.max_node_size, GFP_KERNEL);
 359        if (!node)
 360                return;
 361
 362        for (nodenum = 0; nodenum < 0xff;) {
 363                u8 thisnodenum = nodenum;
 364                /* eventually we will want to use PNPMODE_STATIC here but for now
 365                 * dynamic will help us catch buggy bioses to add to the blacklist.
 366                 */
 367                if (!pnpbios_dont_use_current_config) {
 368                        if (pnp_bios_get_dev_node
 369                            (&nodenum, (char)PNPMODE_DYNAMIC, node))
 370                                break;
 371                } else {
 372                        if (pnp_bios_get_dev_node
 373                            (&nodenum, (char)PNPMODE_STATIC, node))
 374                                break;
 375                }
 376                nodes_got++;
 377                if (insert_device(node) == 0)
 378                        devs++;
 379                if (nodenum <= thisnodenum) {
 380                        printk(KERN_ERR
 381                               "PnPBIOS: build_devlist: Node number 0x%x is out of sequence following node 0x%x. Aborting.\n",
 382                               (unsigned int)nodenum,
 383                               (unsigned int)thisnodenum);
 384                        break;
 385                }
 386        }
 387        kfree(node);
 388
 389        printk(KERN_INFO
 390               "PnPBIOS: %i node%s reported by PnP BIOS; %i recorded by driver\n",
 391               nodes_got, nodes_got != 1 ? "s" : "", devs);
 392}
 393
 394/*
 395 *
 396 * INIT AND EXIT
 397 *
 398 */
 399
 400static int pnpbios_disabled;
 401int pnpbios_dont_use_current_config;
 402
 403static int __init pnpbios_setup(char *str)
 404{
 405        int invert;
 406
 407        while ((str != NULL) && (*str != '\0')) {
 408                if (strncmp(str, "off", 3) == 0)
 409                        pnpbios_disabled = 1;
 410                if (strncmp(str, "on", 2) == 0)
 411                        pnpbios_disabled = 0;
 412                invert = (strncmp(str, "no-", 3) == 0);
 413                if (invert)
 414                        str += 3;
 415                if (strncmp(str, "curr", 4) == 0)
 416                        pnpbios_dont_use_current_config = invert;
 417                str = strchr(str, ',');
 418                if (str != NULL)
 419                        str += strspn(str, ", \t");
 420        }
 421
 422        return 1;
 423}
 424
 425__setup("pnpbios=", pnpbios_setup);
 426
 427/* PnP BIOS signature: "$PnP" */
 428#define PNP_SIGNATURE   (('$' << 0) + ('P' << 8) + ('n' << 16) + ('P' << 24))
 429
 430static int __init pnpbios_probe_system(void)
 431{
 432        union pnp_bios_install_struct *check;
 433        u8 sum;
 434        int length, i;
 435
 436        printk(KERN_INFO "PnPBIOS: Scanning system for PnP BIOS support...\n");
 437
 438        /*
 439         * Search the defined area (0xf0000-0xffff0) for a valid PnP BIOS
 440         * structure and, if one is found, sets up the selectors and
 441         * entry points
 442         */
 443        for (check = (union pnp_bios_install_struct *)__va(0xf0000);
 444             check < (union pnp_bios_install_struct *)__va(0xffff0);
 445             check = (void *)check + 16) {
 446                if (check->fields.signature != PNP_SIGNATURE)
 447                        continue;
 448                printk(KERN_INFO
 449                       "PnPBIOS: Found PnP BIOS installation structure at 0x%p\n",
 450                       check);
 451                length = check->fields.length;
 452                if (!length) {
 453                        printk(KERN_ERR
 454                               "PnPBIOS: installation structure is invalid, skipping\n");
 455                        continue;
 456                }
 457                for (sum = 0, i = 0; i < length; i++)
 458                        sum += check->chars[i];
 459                if (sum) {
 460                        printk(KERN_ERR
 461                               "PnPBIOS: installation structure is corrupted, skipping\n");
 462                        continue;
 463                }
 464                if (check->fields.version < 0x10) {
 465                        printk(KERN_WARNING
 466                               "PnPBIOS: PnP BIOS version %d.%d is not supported\n",
 467                               check->fields.version >> 4,
 468                               check->fields.version & 15);
 469                        continue;
 470                }
 471                printk(KERN_INFO
 472                       "PnPBIOS: PnP BIOS version %d.%d, entry 0x%x:0x%x, dseg 0x%x\n",
 473                       check->fields.version >> 4, check->fields.version & 15,
 474                       check->fields.pm16cseg, check->fields.pm16offset,
 475                       check->fields.pm16dseg);
 476                pnp_bios_install = check;
 477                return 1;
 478        }
 479
 480        printk(KERN_INFO "PnPBIOS: PnP BIOS support was not detected.\n");
 481        return 0;
 482}
 483
 484static int __init exploding_pnp_bios(const struct dmi_system_id *d)
 485{
 486        printk(KERN_WARNING "%s detected. Disabling PnPBIOS\n", d->ident);
 487        return 0;
 488}
 489
 490static struct dmi_system_id pnpbios_dmi_table[] __initdata = {
 491        {                       /* PnPBIOS GPF on boot */
 492         .callback = exploding_pnp_bios,
 493         .ident = "Higraded P14H",
 494         .matches = {
 495                     DMI_MATCH(DMI_BIOS_VENDOR, "American Megatrends Inc."),
 496                     DMI_MATCH(DMI_BIOS_VERSION, "07.00T"),
 497                     DMI_MATCH(DMI_SYS_VENDOR, "Higraded"),
 498                     DMI_MATCH(DMI_PRODUCT_NAME, "P14H"),
 499                     },
 500         },
 501        {                       /* PnPBIOS GPF on boot */
 502         .callback = exploding_pnp_bios,
 503         .ident = "ASUS P4P800",
 504         .matches = {
 505                     DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer Inc."),
 506                     DMI_MATCH(DMI_BOARD_NAME, "P4P800"),
 507                     },
 508         },
 509        {}
 510};
 511
 512static int __init pnpbios_init(void)
 513{
 514        int ret;
 515
 516#if defined(CONFIG_PPC)
 517        if (check_legacy_ioport(PNPBIOS_BASE))
 518                return -ENODEV;
 519#endif
 520        if (pnpbios_disabled || dmi_check_system(pnpbios_dmi_table) ||
 521            paravirt_enabled()) {
 522                printk(KERN_INFO "PnPBIOS: Disabled\n");
 523                return -ENODEV;
 524        }
 525#ifdef CONFIG_PNPACPI
 526        if (!acpi_disabled && !pnpacpi_disabled) {
 527                pnpbios_disabled = 1;
 528                printk(KERN_INFO "PnPBIOS: Disabled by ACPI PNP\n");
 529                return -ENODEV;
 530        }
 531#endif                          /* CONFIG_ACPI */
 532
 533        /* scan the system for pnpbios support */
 534        if (!pnpbios_probe_system())
 535                return -ENODEV;
 536
 537        /* make preparations for bios calls */
 538        pnpbios_calls_init(pnp_bios_install);
 539
 540        /* read the node info */
 541        ret = pnp_bios_dev_node_info(&node_info);
 542        if (ret) {
 543                printk(KERN_ERR
 544                       "PnPBIOS: Unable to get node info.  Aborting.\n");
 545                return ret;
 546        }
 547
 548        /* register with the pnp layer */
 549        ret = pnp_register_protocol(&pnpbios_protocol);
 550        if (ret) {
 551                printk(KERN_ERR
 552                       "PnPBIOS: Unable to register driver.  Aborting.\n");
 553                return ret;
 554        }
 555
 556        /* start the proc interface */
 557        ret = pnpbios_proc_init();
 558        if (ret)
 559                printk(KERN_ERR "PnPBIOS: Failed to create proc interface.\n");
 560
 561        /* scan for pnpbios devices */
 562        build_devlist();
 563
 564        pnp_platform_devices = 1;
 565        return 0;
 566}
 567
 568fs_initcall(pnpbios_init);
 569
 570static int __init pnpbios_thread_init(void)
 571{
 572        struct task_struct *task;
 573#if defined(CONFIG_PPC)
 574        if (check_legacy_ioport(PNPBIOS_BASE))
 575                return 0;
 576#endif
 577        if (pnpbios_disabled)
 578                return 0;
 579
 580        init_completion(&unload_sem);
 581        task = kthread_run(pnp_dock_thread, NULL, "kpnpbiosd");
 582        if (IS_ERR(task))
 583                return PTR_ERR(task);
 584
 585        return 0;
 586}
 587
 588/* Start the kernel thread later: */
 589module_init(pnpbios_thread_init);
 590
 591EXPORT_SYMBOL(pnpbios_protocol);
 592