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   1 /*
   2  *  acpi_system.c - ACPI System Driver ($Revision: 63 $)
   3  *
   4  *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
   5  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
   6  *
   7  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   8  *
   9  *  This program is free software; you can redistribute it and/or modify
  10  *  it under the terms of the GNU General Public License as published by
  11  *  the Free Software Foundation; either version 2 of the License, or (at
  12  *  your option) any later version.
  13  *
  14  *  This program is distributed in the hope that it will be useful, but
  15  *  WITHOUT ANY WARRANTY; without even the implied warranty of
  16  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  17  *  General Public License for more details.
  18  *
  19  *  You should have received a copy of the GNU General Public License along
  20  *  with this program; if not, write to the Free Software Foundation, Inc.,
  21  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
  22  *
  23  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  24  */
  25
  26 #include <linux/proc_fs.h>
  27 #include <linux/seq_file.h>
  28 #include <linux/init.h>
  29 #include <linux/string.h>
  30 #include <asm/uaccess.h>
  31
  32 #include <acpi/acpi_drivers.h>
  33
  34 #define _COMPONENT              ACPI_SYSTEM_COMPONENT
  35 ACPI_MODULE_NAME("system");
  36 #ifdef MODULE_PARAM_PREFIX
  37 #undef MODULE_PARAM_PREFIX
  38 #endif
  39 #define MODULE_PARAM_PREFIX "acpi."
  40
  41 #define ACPI_SYSTEM_CLASS               "system"
  42 #define ACPI_SYSTEM_DEVICE_NAME         "System"
  43
  44 u32 acpi_irq_handled;
  45
  46 /*
  47  * Make ACPICA version work as module param
  48  */
  49 static int param_get_acpica_version(char *buffer, struct kernel_param *kp)
  50 {
  51         int result;
  52
  53         result = sprintf(buffer, "%x", ACPI_CA_VERSION);
  54
  55         return result;
  56 }
  57
  58 module_param_call(acpica_version, NULL, param_get_acpica_version, NULL, 0444);
  59
  60 /* --------------------------------------------------------------------------
  61                               FS Interface (/sys)
  62    -------------------------------------------------------------------------- */
  63 static LIST_HEAD(acpi_table_attr_list);
  64 static struct kobject *tables_kobj;
  65
  66 struct acpi_table_attr {
  67         struct bin_attribute attr;
  68         char name[8];
  69         int instance;
  70         struct list_head node;
  71 };
  72
  73 static ssize_t acpi_table_show(struct kobject *kobj,
  74                                struct bin_attribute *bin_attr, char *buf,
  75                                loff_t offset, size_t count)
  76 {
  77         struct acpi_table_attr *table_attr =
  78             container_of(bin_attr, struct acpi_table_attr, attr);
  79         struct acpi_table_header *table_header = NULL;
  80         acpi_status status;
  81
  82         status =
  83             acpi_get_table(table_attr->name, table_attr->instance,
  84                            &table_header);
  85         if (ACPI_FAILURE(status))
  86                 return -ENODEV;
  87
  88         return memory_read_from_buffer(buf, count, &offset,
  89                                         table_header, table_header->length);
  90 }
  91
  92 static void acpi_table_attr_init(struct acpi_table_attr *table_attr,
  93                                  struct acpi_table_header *table_header)
  94 {
  95         struct acpi_table_header *header = NULL;
  96         struct acpi_table_attr *attr = NULL;
  97
  98         memcpy(table_attr->name, table_header->signature, ACPI_NAME_SIZE);
  99
 100         list_for_each_entry(attr, &acpi_table_attr_list, node) {
 101                 if (!memcmp(table_header->signature, attr->name,
 102                             ACPI_NAME_SIZE))
 103                         if (table_attr->instance < attr->instance)
 104                                 table_attr->instance = attr->instance;
 105         }
 106         table_attr->instance++;
 107
 108         if (table_attr->instance > 1 || (table_attr->instance == 1 &&
 109                                          !acpi_get_table(table_header->
 110                                                          signature, 2,
 111                                                          &header)))
 112                 sprintf(table_attr->name + 4, "%d", table_attr->instance);
 113
 114         table_attr->attr.size = 0;
 115         table_attr->attr.read = acpi_table_show;
 116         table_attr->attr.attr.name = table_attr->name;
 117         table_attr->attr.attr.mode = 0444;
 118         table_attr->attr.attr.owner = THIS_MODULE;
 119
 120         return;
 121 }
 122
 123 static int acpi_system_sysfs_init(void)
 124 {
 125         struct acpi_table_attr *table_attr;
 126         struct acpi_table_header *table_header = NULL;
 127         int table_index = 0;
 128         int result;
 129
 130         tables_kobj = kobject_create_and_add("tables", acpi_kobj);
 131         if (!tables_kobj)
 132                 return -ENOMEM;
 133
 134         do {
 135                 result = acpi_get_table_by_index(table_index, &table_header);
 136                 if (!result) {
 137                         table_index++;
 138                         table_attr = NULL;
 139                         table_attr =
 140                             kzalloc(sizeof(struct acpi_table_attr), GFP_KERNEL);
 141                         if (!table_attr)
 142                                 return -ENOMEM;
 143
 144                         acpi_table_attr_init(table_attr, table_header);
 145                         result =
 146                             sysfs_create_bin_file(tables_kobj,
 147                                                   &table_attr->attr);
 148                         if (result) {
 149                                 kfree(table_attr);
 150                                 return result;
 151                         } else
 152                                 list_add_tail(&table_attr->node,
 153                                               &acpi_table_attr_list);
 154                 }
 155         } while (!result);
 156         kobject_uevent(tables_kobj, KOBJ_ADD);
 157
 158         return 0;
 159 }
 160
 161 /*
 162  * Detailed ACPI IRQ counters in /sys/firmware/acpi/interrupts/
 163  * See Documentation/ABI/testing/sysfs-firmware-acpi
 164  */
 165
 166 #define COUNT_GPE 0
 167 #define COUNT_SCI 1     /* acpi_irq_handled */
 168 #define COUNT_ERROR 2   /* other */
 169 #define NUM_COUNTERS_EXTRA 3
 170
 171 #define ACPI_EVENT_VALID        0x01
 172 struct event_counter {
 173         u32 count;
 174         u32 flags;
 175 };
 176
 177 static struct event_counter *all_counters;
 178 static u32 num_gpes;
 179 static u32 num_counters;
 180 static struct attribute **all_attrs;
 181 static u32 acpi_gpe_count;
 182
 183 static struct attribute_group interrupt_stats_attr_group = {
 184         .name = "interrupts",
 185 };
 186 static struct kobj_attribute *counter_attrs;
 187
 188 static int count_num_gpes(void)
 189 {
 190         int count = 0;
 191         struct acpi_gpe_xrupt_info *gpe_xrupt_info;
 192         struct acpi_gpe_block_info *gpe_block;
 193         acpi_cpu_flags flags;
 194
 195         flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
 196
 197         gpe_xrupt_info = acpi_gbl_gpe_xrupt_list_head;
 198         while (gpe_xrupt_info) {
 199                 gpe_block = gpe_xrupt_info->gpe_block_list_head;
 200                 while (gpe_block) {
 201                         count += gpe_block->register_count *
 202                             ACPI_GPE_REGISTER_WIDTH;
 203                         gpe_block = gpe_block->next;
 204                 }
 205                 gpe_xrupt_info = gpe_xrupt_info->next;
 206         }
 207         acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
 208
 209         return count;
 210 }
 211
 212 static int get_gpe_device(int index, acpi_handle *handle)
 213 {
 214         struct acpi_gpe_xrupt_info *gpe_xrupt_info;
 215         struct acpi_gpe_block_info *gpe_block;
 216         acpi_cpu_flags flags;
 217         struct acpi_namespace_node *node;
 218
 219         flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
 220
 221         gpe_xrupt_info = acpi_gbl_gpe_xrupt_list_head;
 222         while (gpe_xrupt_info) {
 223                 gpe_block = gpe_xrupt_info->gpe_block_list_head;
 224                 node = gpe_block->node;
 225                 while (gpe_block) {
 226                         index -= gpe_block->register_count *
 227                             ACPI_GPE_REGISTER_WIDTH;
 228                         if (index < 0) {
 229                                 acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
 230                                 /* return NULL if it's FADT GPE */
 231                                 if (node->type != ACPI_TYPE_DEVICE)
 232                                         *handle = NULL;
 233                                 else
 234                                         *handle = node;
 235                                 return 0;
 236                         }
 237                         node = gpe_block->node;
 238                         gpe_block = gpe_block->next;
 239                 }
 240                 gpe_xrupt_info = gpe_xrupt_info->next;
 241         }
 242         acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
 243
 244         return -ENODEV;
 245 }
 246
 247 static void delete_gpe_attr_array(void)
 248 {
 249         struct event_counter *tmp = all_counters;
 250
 251         all_counters = NULL;
 252         kfree(tmp);
 253
 254         if (counter_attrs) {
 255                 int i;
 256
 257                 for (i = 0; i < num_gpes; i++)
 258                         kfree(counter_attrs[i].attr.name);
 259
 260                 kfree(counter_attrs);
 261         }
 262         kfree(all_attrs);
 263
 264         return;
 265 }
 266
 267 void acpi_os_gpe_count(u32 gpe_number)
 268 {
 269         acpi_gpe_count++;
 270
 271         if (!all_counters)
 272                 return;
 273
 274         if (gpe_number < num_gpes)
 275                 all_counters[gpe_number].count++;
 276         else
 277                 all_counters[num_gpes + ACPI_NUM_FIXED_EVENTS + COUNT_ERROR].
 278                                         count++;
 279
 280         return;
 281 }
 282
 283 void acpi_os_fixed_event_count(u32 event_number)
 284 {
 285         if (!all_counters)
 286                 return;
 287
 288         if (event_number < ACPI_NUM_FIXED_EVENTS)
 289                 all_counters[num_gpes + event_number].count++;
 290         else
 291                 all_counters[num_gpes + ACPI_NUM_FIXED_EVENTS + COUNT_ERROR].
 292                                 count++;
 293
 294         return;
 295 }
 296
 297 static int get_status(u32 index, acpi_event_status *status, acpi_handle *handle)
 298 {
 299         int result = 0;
 300
 301         if (index >= num_gpes + ACPI_NUM_FIXED_EVENTS)
 302                 goto end;
 303
 304         if (index < num_gpes) {
 305                 result = get_gpe_device(index, handle);
 306                 if (result) {
 307                         ACPI_EXCEPTION((AE_INFO, AE_NOT_FOUND,
 308                                 "Invalid GPE 0x%x\n", index));
 309                         goto end;
 310                 }
 311                 result = acpi_get_gpe_status(*handle, index,
 312                                                 ACPI_NOT_ISR, status);
 313         } else if (index < (num_gpes + ACPI_NUM_FIXED_EVENTS))
 314                 result = acpi_get_event_status(index - num_gpes, status);
 315
 316         /*
 317          * sleep/power button GPE/Fixed Event is enabled after acpi_system_init,
 318          * check the status at runtime and mark it as valid once it's enabled
 319          */
 320         if (!result && (*status & ACPI_EVENT_FLAG_ENABLED))
 321                 all_counters[index].flags |= ACPI_EVENT_VALID;
 322 end:
 323         return result;
 324 }
 325
 326 static ssize_t counter_show(struct kobject *kobj,
 327         struct kobj_attribute *attr, char *buf)
 328 {
 329         int index = attr - counter_attrs;
 330         int size;
 331         acpi_handle handle;
 332         acpi_event_status status;
 333         int result = 0;
 334
 335         all_counters[num_gpes + ACPI_NUM_FIXED_EVENTS + COUNT_SCI].count =
 336                 acpi_irq_handled;
 337         all_counters[num_gpes + ACPI_NUM_FIXED_EVENTS + COUNT_GPE].count =
 338                 acpi_gpe_count;
 339
 340         size = sprintf(buf, "%8d", all_counters[index].count);
 341
 342         /* "gpe_all" or "sci" */
 343         if (index >= num_gpes + ACPI_NUM_FIXED_EVENTS)
 344                 goto end;
 345
 346         result = get_status(index, &status, &handle);
 347         if (result)
 348                 goto end;
 349
 350         if (!(all_counters[index].flags & ACPI_EVENT_VALID))
 351                 size += sprintf(buf + size, "  invalid");
 352         else if (status & ACPI_EVENT_FLAG_ENABLED)
 353                 size += sprintf(buf + size, "   enable");
 354         else
 355                 size += sprintf(buf + size, "  disable");
 356
 357 end:
 358         size += sprintf(buf + size, "\n");
 359         return result ? result : size;
 360 }
 361
 362 /*
 363  * counter_set() sets the specified counter.
 364  * setting the total "sci" file to any value clears all counters.
 365  * enable/disable/clear a gpe/fixed event in user space.
 366  */
 367 static ssize_t counter_set(struct kobject *kobj,
 368         struct kobj_attribute *attr, const char *buf, size_t size)
 369 {
 370         int index = attr - counter_attrs;
 371         acpi_event_status status;
 372         acpi_handle handle;
 373         int result = 0;
 374
 375         if (index == num_gpes + ACPI_NUM_FIXED_EVENTS + COUNT_SCI) {
 376                 int i;
 377                 for (i = 0; i < num_counters; ++i)
 378                         all_counters[i].count = 0;
 379                 acpi_gpe_count = 0;
 380                 acpi_irq_handled = 0;
 381                 goto end;
 382         }
 383
 384         /* show the event status for both GPEs and Fixed Events */
 385         result = get_status(index, &status, &handle);
 386         if (result)
 387                 goto end;
 388
 389         if (!(all_counters[index].flags & ACPI_EVENT_VALID)) {
 390                 ACPI_DEBUG_PRINT((ACPI_DB_WARN,
 391                         "Can not change Invalid GPE/Fixed Event status\n"));
 392                 return -EINVAL;
 393         }
 394
 395         if (index < num_gpes) {
 396                 if (!strcmp(buf, "disable\n") &&
 397                                 (status & ACPI_EVENT_FLAG_ENABLED))
 398                         result = acpi_disable_gpe(handle, index, ACPI_NOT_ISR);
 399                 else if (!strcmp(buf, "enable\n") &&
 400                                 !(status & ACPI_EVENT_FLAG_ENABLED))
 401                         result = acpi_enable_gpe(handle, index, ACPI_NOT_ISR);
 402                 else if (!strcmp(buf, "clear\n") &&
 403                                 (status & ACPI_EVENT_FLAG_SET))
 404                         result = acpi_clear_gpe(handle, index, ACPI_NOT_ISR);
 405                 else
 406                         all_counters[index].count = strtoul(buf, NULL, 0);
 407         } else if (index < num_gpes + ACPI_NUM_FIXED_EVENTS) {
 408                 int event = index - num_gpes;
 409                 if (!strcmp(buf, "disable\n") &&
 410                                 (status & ACPI_EVENT_FLAG_ENABLED))
 411                         result = acpi_disable_event(event, ACPI_NOT_ISR);
 412                 else if (!strcmp(buf, "enable\n") &&
 413                                 !(status & ACPI_EVENT_FLAG_ENABLED))
 414                         result = acpi_enable_event(event, ACPI_NOT_ISR);
 415                 else if (!strcmp(buf, "clear\n") &&
 416                                 (status & ACPI_EVENT_FLAG_SET))
 417                         result = acpi_clear_event(event);
 418                 else
 419                         all_counters[index].count = strtoul(buf, NULL, 0);
 420         } else
 421                 all_counters[index].count = strtoul(buf, NULL, 0);
 422
 423         if (ACPI_FAILURE(result))
 424                 result = -EINVAL;
 425 end:
 426         return result ? result : size;
 427 }
 428
 429 void acpi_irq_stats_init(void)
 430 {
 431         int i;
 432
 433         if (all_counters)
 434                 return;
 435
 436         num_gpes = count_num_gpes();
 437         num_counters = num_gpes + ACPI_NUM_FIXED_EVENTS + NUM_COUNTERS_EXTRA;
 438
 439         all_attrs = kzalloc(sizeof(struct attribute *) * (num_counters + 1),
 440                         GFP_KERNEL);
 441         if (all_attrs == NULL)
 442                 return;
 443
 444         all_counters = kzalloc(sizeof(struct event_counter) * (num_counters),
 445                                 GFP_KERNEL);
 446         if (all_counters == NULL)
 447                 goto fail;
 448
 449         counter_attrs = kzalloc(sizeof(struct kobj_attribute) * (num_counters),
 450                         GFP_KERNEL);
 451         if (counter_attrs == NULL)
 452                 goto fail;
 453
 454         for (i = 0; i < num_counters; ++i) {
 455                 char buffer[12];
 456                 char *name;
 457
 458                 if (i < num_gpes)
 459                         sprintf(buffer, "gpe%02X", i);
 460                 else if (i == num_gpes + ACPI_EVENT_PMTIMER)
 461                         sprintf(buffer, "ff_pmtimer");
 462                 else if (i == num_gpes + ACPI_EVENT_GLOBAL)
 463                         sprintf(buffer, "ff_gbl_lock");
 464                 else if (i == num_gpes + ACPI_EVENT_POWER_BUTTON)
 465                         sprintf(buffer, "ff_pwr_btn");
 466                 else if (i == num_gpes + ACPI_EVENT_SLEEP_BUTTON)
 467                         sprintf(buffer, "ff_slp_btn");
 468                 else if (i == num_gpes + ACPI_EVENT_RTC)
 469                         sprintf(buffer, "ff_rt_clk");
 470                 else if (i == num_gpes + ACPI_NUM_FIXED_EVENTS + COUNT_GPE)
 471                         sprintf(buffer, "gpe_all");
 472                 else if (i == num_gpes + ACPI_NUM_FIXED_EVENTS + COUNT_SCI)
 473                         sprintf(buffer, "sci");
 474                 else if (i == num_gpes + ACPI_NUM_FIXED_EVENTS + COUNT_ERROR)
 475                         sprintf(buffer, "error");
 476                 else
 477                         sprintf(buffer, "bug%02X", i);
 478
 479                 name = kzalloc(strlen(buffer) + 1, GFP_KERNEL);
 480                 if (name == NULL)
 481                         goto fail;
 482                 strncpy(name, buffer, strlen(buffer) + 1);
 483
 484                 counter_attrs[i].attr.name = name;
 485                 counter_attrs[i].attr.mode = 0644;
 486                 counter_attrs[i].show = counter_show;
 487                 counter_attrs[i].store = counter_set;
 488
 489                 all_attrs[i] = &counter_attrs[i].attr;
 490         }
 491
 492         interrupt_stats_attr_group.attrs = all_attrs;
 493         if (!sysfs_create_group(acpi_kobj, &interrupt_stats_attr_group))
 494                 return;
 495
 496 fail:
 497         delete_gpe_attr_array();
 498         return;
 499 }
 500
 501 static void __exit interrupt_stats_exit(void)
 502 {
 503         sysfs_remove_group(acpi_kobj, &interrupt_stats_attr_group);
 504
 505         delete_gpe_attr_array();
 506
 507         return;
 508 }
 509
 510 /* --------------------------------------------------------------------------
 511                               FS Interface (/proc)
 512    -------------------------------------------------------------------------- */
 513 #ifdef CONFIG_ACPI_PROCFS
 514 #define ACPI_SYSTEM_FILE_INFO           "info"
 515 #define ACPI_SYSTEM_FILE_EVENT          "event"
 516 #define ACPI_SYSTEM_FILE_DSDT           "dsdt"
 517 #define ACPI_SYSTEM_FILE_FADT           "fadt"
 518
 519 static int acpi_system_read_info(struct seq_file *seq, void *offset)
 520 {
 521
 522         seq_printf(seq, "version:                 %x\n", ACPI_CA_VERSION);
 523         return 0;
 524 }
 525
 526 static int acpi_system_info_open_fs(struct inode *inode, struct file *file)
 527 {
 528         return single_open(file, acpi_system_read_info, PDE(inode)->data);
 529 }
 530
 531 static const struct file_operations acpi_system_info_ops = {
 532         .owner = THIS_MODULE,
 533         .open = acpi_system_info_open_fs,
 534         .read = seq_read,
 535         .llseek = seq_lseek,
 536         .release = single_release,
 537 };
 538
 539 static ssize_t acpi_system_read_dsdt(struct file *, char __user *, size_t,
 540                                      loff_t *);
 541
 542 static const struct file_operations acpi_system_dsdt_ops = {
 543         .owner = THIS_MODULE,
 544         .read = acpi_system_read_dsdt,
 545 };
 546
 547 static ssize_t
 548 acpi_system_read_dsdt(struct file *file,
 549                       char __user * buffer, size_t count, loff_t * ppos)
 550 {
 551         acpi_status status = AE_OK;
 552         struct acpi_table_header *dsdt = NULL;
 553         ssize_t res;
 554
 555         status = acpi_get_table(ACPI_SIG_DSDT, 1, &dsdt);
 556         if (ACPI_FAILURE(status))
 557                 return -ENODEV;
 558
 559         res = simple_read_from_buffer(buffer, count, ppos, dsdt, dsdt->length);
 560
 561         return res;
 562 }
 563
 564 static ssize_t acpi_system_read_fadt(struct file *, char __user *, size_t,
 565                                      loff_t *);
 566
 567 static const struct file_operations acpi_system_fadt_ops = {
 568         .owner = THIS_MODULE,
 569         .read = acpi_system_read_fadt,
 570 };
 571
 572 static ssize_t
 573 acpi_system_read_fadt(struct file *file,
 574                       char __user * buffer, size_t count, loff_t * ppos)
 575 {
 576         acpi_status status = AE_OK;
 577         struct acpi_table_header *fadt = NULL;
 578         ssize_t res;
 579
 580         status = acpi_get_table(ACPI_SIG_FADT, 1, &fadt);
 581         if (ACPI_FAILURE(status))
 582                 return -ENODEV;
 583
 584         res = simple_read_from_buffer(buffer, count, ppos, fadt, fadt->length);
 585
 586         return res;
 587 }
 588
 589 static int acpi_system_procfs_init(void)
 590 {
 591         struct proc_dir_entry *entry;
 592         int error = 0;
 593
 594         /* 'info' [R] */
 595         entry = proc_create(ACPI_SYSTEM_FILE_INFO, S_IRUGO, acpi_root_dir,
 596                             &acpi_system_info_ops);
 597         if (!entry)
 598                 goto Error;
 599
 600         /* 'dsdt' [R] */
 601         entry = proc_create(ACPI_SYSTEM_FILE_DSDT, S_IRUSR, acpi_root_dir,
 602                             &acpi_system_dsdt_ops);
 603         if (!entry)
 604                 goto Error;
 605
 606         /* 'fadt' [R] */
 607         entry = proc_create(ACPI_SYSTEM_FILE_FADT, S_IRUSR, acpi_root_dir,
 608                             &acpi_system_fadt_ops);
 609         if (!entry)
 610                 goto Error;
 611
 612       Done:
 613         return error;
 614
 615       Error:
 616         remove_proc_entry(ACPI_SYSTEM_FILE_FADT, acpi_root_dir);
 617         remove_proc_entry(ACPI_SYSTEM_FILE_DSDT, acpi_root_dir);
 618         remove_proc_entry(ACPI_SYSTEM_FILE_INFO, acpi_root_dir);
 619
 620         error = -EFAULT;
 621         goto Done;
 622 }
 623 #else
 624 static int acpi_system_procfs_init(void)
 625 {
 626         return 0;
 627 }
 628 #endif
 629
 630 static int __init acpi_system_init(void)
 631 {
 632         int result = 0;
 633
 634         if (acpi_disabled)
 635                 return 0;
 636
 637         result = acpi_system_procfs_init();
 638         if (result)
 639                 return result;
 640
 641         result = acpi_system_sysfs_init();
 642
 643         return result;
 644 }
 645
 646 subsys_initcall(acpi_system_init);