err.no Git - linux-2.6/blob - drivers/acpi/ec.c

   1 /*
   2  *  acpi_ec.c - ACPI Embedded Controller Driver ($Revision: 38 $)
   3  *
   4  *  Copyright (C) 2004 Luming Yu <luming.yu@intel.com>
   5  *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
   6  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
   7  *
   8  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   9  *
  10  *  This program is free software; you can redistribute it and/or modify
  11  *  it under the terms of the GNU General Public License as published by
  12  *  the Free Software Foundation; either version 2 of the License, or (at
  13  *  your option) any later version.
  14  *
  15  *  This program is distributed in the hope that it will be useful, but
  16  *  WITHOUT ANY WARRANTY; without even the implied warranty of
  17  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  18  *  General Public License for more details.
  19  *
  20  *  You should have received a copy of the GNU General Public License along
  21  *  with this program; if not, write to the Free Software Foundation, Inc.,
  22  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
  23  *
  24  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  25  */
  26
  27 #include <linux/kernel.h>
  28 #include <linux/module.h>
  29 #include <linux/init.h>
  30 #include <linux/types.h>
  31 #include <linux/delay.h>
  32 #include <linux/proc_fs.h>
  33 #include <linux/seq_file.h>
  34 #include <linux/interrupt.h>
  35 #include <asm/io.h>
  36 #include <acpi/acpi_bus.h>
  37 #include <acpi/acpi_drivers.h>
  38 #include <acpi/actypes.h>
  39
  40 #define _COMPONENT              ACPI_EC_COMPONENT
  41 ACPI_MODULE_NAME("acpi_ec")
  42 #define ACPI_EC_COMPONENT               0x00100000
  43 #define ACPI_EC_CLASS                   "embedded_controller"
  44 #define ACPI_EC_HID                     "PNP0C09"
  45 #define ACPI_EC_DRIVER_NAME             "ACPI Embedded Controller Driver"
  46 #define ACPI_EC_DEVICE_NAME             "Embedded Controller"
  47 #define ACPI_EC_FILE_INFO               "info"
  48 #undef PREFIX
  49 #define PREFIX                          "ACPI: EC: "
  50 /* EC status register */
  51 #define ACPI_EC_FLAG_OBF        0x01    /* Output buffer full */
  52 #define ACPI_EC_FLAG_IBF        0x02    /* Input buffer full */
  53 #define ACPI_EC_FLAG_BURST      0x10    /* burst mode */
  54 #define ACPI_EC_FLAG_SCI        0x20    /* EC-SCI occurred */
  55 /* EC commands */
  56 enum ec_command {
  57         ACPI_EC_COMMAND_READ = 0x80,
  58         ACPI_EC_COMMAND_WRITE = 0x81,
  59         ACPI_EC_BURST_ENABLE = 0x82,
  60         ACPI_EC_BURST_DISABLE = 0x83,
  61         ACPI_EC_COMMAND_QUERY = 0x84,
  62 };
  63 /* EC events */
  64 enum ec_event {
  65         ACPI_EC_EVENT_OBF_1 = 1,        /* Output buffer full */
  66         ACPI_EC_EVENT_IBF_0,    /* Input buffer empty */
  67 };
  68
  69 #define ACPI_EC_DELAY           500     /* Wait 500ms max. during EC ops */
  70 #define ACPI_EC_UDELAY_GLK      1000    /* Wait 1ms max. to get global lock */
  71
  72 static enum ec_mode {
  73         EC_INTR = 1,            /* Output buffer full */
  74         EC_POLL,                /* Input buffer empty */
  75 } acpi_ec_mode = EC_INTR;
  76
  77 static int acpi_ec_remove(struct acpi_device *device, int type);
  78 static int acpi_ec_start(struct acpi_device *device);
  79 static int acpi_ec_stop(struct acpi_device *device, int type);
  80 static int acpi_ec_add(struct acpi_device *device);
  81
  82 static struct acpi_driver acpi_ec_driver = {
  83         .name = ACPI_EC_DRIVER_NAME,
  84         .class = ACPI_EC_CLASS,
  85         .ids = ACPI_EC_HID,
  86         .ops = {
  87                 .add = acpi_ec_add,
  88                 .remove = acpi_ec_remove,
  89                 .start = acpi_ec_start,
  90                 .stop = acpi_ec_stop,
  91                 },
  92 };
  93
  94 /* If we find an EC via the ECDT, we need to keep a ptr to its context */
  95 static struct acpi_ec {
  96         acpi_handle handle;
  97         unsigned long uid;
  98         unsigned long gpe;
  99         unsigned long command_addr;
 100         unsigned long data_addr;
 101         unsigned long global_lock;
 102         struct mutex lock;
 103         atomic_t query_pending;
 104         atomic_t leaving_burst; /* 0 : No, 1 : Yes, 2: abort */
 105         wait_queue_head_t wait;
 106 } *ec_ecdt;
 107
 108 /* External interfaces use first EC only, so remember */
 109 static struct acpi_device *first_ec;
 110
 111 /* --------------------------------------------------------------------------
 112                              Transaction Management
 113    -------------------------------------------------------------------------- */
 114
 115 static inline u8 acpi_ec_read_status(struct acpi_ec *ec)
 116 {
 117         return inb(ec->command_addr);
 118 }
 119
 120 static inline u8 acpi_ec_read_data(struct acpi_ec *ec)
 121 {
 122         return inb(ec->data_addr);
 123 }
 124
 125 static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command)
 126 {
 127         outb(command, ec->command_addr);
 128 }
 129
 130 static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data)
 131 {
 132         outb(data, ec->data_addr);
 133 }
 134
 135 static inline int acpi_ec_check_status(struct acpi_ec *ec, enum ec_event event)
 136 {
 137         u8 status = acpi_ec_read_status(ec);
 138
 139         if (event == ACPI_EC_EVENT_OBF_1) {
 140                 if (status & ACPI_EC_FLAG_OBF)
 141                         return 1;
 142         } else if (event == ACPI_EC_EVENT_IBF_0) {
 143                 if (!(status & ACPI_EC_FLAG_IBF))
 144                         return 1;
 145         }
 146
 147         return 0;
 148 }
 149
 150 static int acpi_ec_wait(struct acpi_ec *ec, enum ec_event event)
 151 {
 152         if (acpi_ec_mode == EC_POLL) {
 153                 unsigned long delay = jiffies + msecs_to_jiffies(ACPI_EC_DELAY);
 154                 while (time_before(jiffies, delay)) {
 155                         if (acpi_ec_check_status(ec, event))
 156                                 return 0;
 157                 }
 158         } else {
 159                 if (wait_event_timeout(ec->wait,
 160                                        acpi_ec_check_status(ec, event),
 161                                        msecs_to_jiffies(ACPI_EC_DELAY)) ||
 162                     acpi_ec_check_status(ec, event)) {
 163                         return 0;
 164                 } else {
 165                         printk(KERN_ERR PREFIX "acpi_ec_wait timeout,"
 166                                " status = %d, expect_event = %d\n",
 167                                acpi_ec_read_status(ec), event);
 168                 }
 169         }
 170
 171         return -ETIME;
 172 }
 173
 174 #ifdef ACPI_FUTURE_USAGE
 175 /*
 176  * Note: samsung nv5000 doesn't work with ec burst mode.
 177  * http://bugzilla.kernel.org/show_bug.cgi?id=4980
 178  */
 179 int acpi_ec_enter_burst_mode(struct acpi_ec *ec)
 180 {
 181         u8 tmp = 0;
 182         u8 status = 0;
 183
 184         status = acpi_ec_read_status(ec);
 185         if (status != -EINVAL && !(status & ACPI_EC_FLAG_BURST)) {
 186                 status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0);
 187                 if (status)
 188                         goto end;
 189                 acpi_ec_write_cmd(ec, ACPI_EC_BURST_ENABLE);
 190                 status = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF_1);
 191                 tmp = acpi_ec_read_data(ec);
 192                 if (tmp != 0x90) {      /* Burst ACK byte */
 193                         return -EINVAL;
 194                 }
 195         }
 196
 197         atomic_set(&ec->leaving_burst, 0);
 198         return 0;
 199       end:
 200         ACPI_EXCEPTION((AE_INFO, status, "EC wait, burst mode"));
 201         return -1;
 202 }
 203
 204 int acpi_ec_leave_burst_mode(struct acpi_ec *ec)
 205 {
 206         u8 status = 0;
 207
 208         status = acpi_ec_read_status(ec);
 209         if (status != -EINVAL && (status & ACPI_EC_FLAG_BURST)) {
 210                 status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0);
 211                 if (status)
 212                         goto end;
 213                 acpi_ec_write_cmd(ec, ACPI_EC_BURST_DISABLE);
 214                 acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0);
 215         }
 216         atomic_set(&ec->leaving_burst, 1);
 217         return 0;
 218       end:
 219         ACPI_EXCEPTION((AE_INFO, status, "EC leave burst mode"));
 220         return -1;
 221 }
 222 #endif                          /* ACPI_FUTURE_USAGE */
 223
 224 static int acpi_ec_transaction_unlocked(struct acpi_ec *ec, u8 command,
 225                                         const u8 * wdata, unsigned wdata_len,
 226                                         u8 * rdata, unsigned rdata_len)
 227 {
 228         int result = 0;
 229
 230         acpi_ec_write_cmd(ec, command);
 231
 232         for (; wdata_len > 0; --wdata_len) {
 233                 result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0);
 234                 if (result) {
 235                         printk(KERN_ERR PREFIX
 236                                "write_cmd timeout, command = %d\n", command);
 237                         goto end;
 238                 }
 239                 acpi_ec_write_data(ec, *(wdata++));
 240         }
 241
 242         if (!rdata_len) {
 243                 result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0);
 244                 if (result) {
 245                         printk(KERN_ERR PREFIX
 246                                "finish-write timeout, command = %d\n", command);
 247                         goto end;
 248                 }
 249         } else if (command == ACPI_EC_COMMAND_QUERY) {
 250                 atomic_set(&ec->query_pending, 0);
 251         }
 252
 253         for (; rdata_len > 0; --rdata_len) {
 254                 result = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF_1);
 255                 if (result) {
 256                         printk(KERN_ERR PREFIX "read timeout, command = %d\n",
 257                                command);
 258                         goto end;
 259                 }
 260
 261                 *(rdata++) = acpi_ec_read_data(ec);
 262         }
 263       end:
 264         return result;
 265 }
 266
 267 static int acpi_ec_transaction(struct acpi_ec *ec, u8 command,
 268                                const u8 * wdata, unsigned wdata_len,
 269                                u8 * rdata, unsigned rdata_len)
 270 {
 271         int status;
 272         u32 glk;
 273
 274         if (!ec || (wdata_len && !wdata) || (rdata_len && !rdata))
 275                 return -EINVAL;
 276
 277         if (rdata)
 278                 memset(rdata, 0, rdata_len);
 279
 280         mutex_lock(&ec->lock);
 281         if (ec->global_lock) {
 282                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 283                 if (ACPI_FAILURE(status)) {
 284                         mutex_unlock(&ec->lock);
 285                         return -ENODEV;
 286                 }
 287         }
 288
 289         /* Make sure GPE is enabled before doing transaction */
 290         acpi_enable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
 291
 292         status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0);
 293         if (status) {
 294                 printk(KERN_DEBUG PREFIX
 295                        "input buffer is not empty, aborting transaction\n");
 296                 goto end;
 297         }
 298
 299         status = acpi_ec_transaction_unlocked(ec, command,
 300                                               wdata, wdata_len,
 301                                               rdata, rdata_len);
 302
 303       end:
 304
 305         if (ec->global_lock)
 306                 acpi_release_global_lock(glk);
 307         mutex_unlock(&ec->lock);
 308
 309         return status;
 310 }
 311
 312 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 * data)
 313 {
 314         int result;
 315         u8 d;
 316
 317         result = acpi_ec_transaction(ec, ACPI_EC_COMMAND_READ,
 318                                      &address, 1, &d, 1);
 319         *data = d;
 320         return result;
 321 }
 322
 323 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
 324 {
 325         u8 wdata[2] = { address, data };
 326         return acpi_ec_transaction(ec, ACPI_EC_COMMAND_WRITE,
 327                                    wdata, 2, NULL, 0);
 328 }
 329
 330 /*
 331  * Externally callable EC access functions. For now, assume 1 EC only
 332  */
 333 int ec_read(u8 addr, u8 * val)
 334 {
 335         struct acpi_ec *ec;
 336         int err;
 337         u8 temp_data;
 338
 339         if (!first_ec)
 340                 return -ENODEV;
 341
 342         ec = acpi_driver_data(first_ec);
 343
 344         err = acpi_ec_read(ec, addr, &temp_data);
 345
 346         if (!err) {
 347                 *val = temp_data;
 348                 return 0;
 349         } else
 350                 return err;
 351 }
 352
 353 EXPORT_SYMBOL(ec_read);
 354
 355 int ec_write(u8 addr, u8 val)
 356 {
 357         struct acpi_ec *ec;
 358         int err;
 359
 360         if (!first_ec)
 361                 return -ENODEV;
 362
 363         ec = acpi_driver_data(first_ec);
 364
 365         err = acpi_ec_write(ec, addr, val);
 366
 367         return err;
 368 }
 369
 370 EXPORT_SYMBOL(ec_write);
 371
 372 int ec_transaction(u8 command,
 373                           const u8 * wdata, unsigned wdata_len,
 374                           u8 * rdata, unsigned rdata_len)
 375 {
 376         struct acpi_ec *ec;
 377
 378         if (!first_ec)
 379                 return -ENODEV;
 380
 381         ec = acpi_driver_data(first_ec);
 382
 383         return acpi_ec_transaction(ec, command, wdata,
 384                                    wdata_len, rdata, rdata_len);
 385 }
 386
 387 EXPORT_SYMBOL(ec_transaction);
 388
 389 static int acpi_ec_query(struct acpi_ec *ec, u8 * data)
 390 {
 391         int result;
 392         u8 d;
 393
 394         if (!ec || !data)
 395                 return -EINVAL;
 396
 397         /*
 398          * Query the EC to find out which _Qxx method we need to evaluate.
 399          * Note that successful completion of the query causes the ACPI_EC_SCI
 400          * bit to be cleared (and thus clearing the interrupt source).
 401          */
 402
 403         result = acpi_ec_transaction(ec, ACPI_EC_COMMAND_QUERY, NULL, 0, &d, 1);
 404         if (result)
 405                 return result;
 406
 407         if (!d)
 408                 return -ENODATA;
 409
 410         *data = d;
 411         return 0;
 412 }
 413
 414 /* --------------------------------------------------------------------------
 415                                 Event Management
 416    -------------------------------------------------------------------------- */
 417
 418 static void acpi_ec_gpe_query(void *ec_cxt)
 419 {
 420         struct acpi_ec *ec = (struct acpi_ec *)ec_cxt;
 421         u8 value = 0;
 422         char object_name[8];
 423
 424         if (!ec || acpi_ec_query(ec, &value))
 425                 return;
 426
 427         snprintf(object_name, 8, "_Q%2.2X", value);
 428
 429         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Evaluating %s", object_name));
 430
 431         acpi_evaluate_object(ec->handle, object_name, NULL, NULL);
 432 }
 433
 434 static u32 acpi_ec_gpe_handler(void *data)
 435 {
 436         acpi_status status = AE_OK;
 437         u8 value;
 438         struct acpi_ec *ec = (struct acpi_ec *)data;
 439
 440         if (acpi_ec_mode == EC_INTR) {
 441                 wake_up(&ec->wait);
 442         }
 443
 444         value = acpi_ec_read_status(ec);
 445         if ((value & ACPI_EC_FLAG_SCI) && !atomic_read(&ec->query_pending)) {
 446                 atomic_set(&ec->query_pending, 1);
 447                 status =
 448                     acpi_os_execute(OSL_EC_BURST_HANDLER, acpi_ec_gpe_query,
 449                                     ec);
 450         }
 451
 452         return status == AE_OK ?
 453             ACPI_INTERRUPT_HANDLED : ACPI_INTERRUPT_NOT_HANDLED;
 454 }
 455
 456 /* --------------------------------------------------------------------------
 457                              Address Space Management
 458    -------------------------------------------------------------------------- */
 459
 460 static acpi_status
 461 acpi_ec_space_setup(acpi_handle region_handle,
 462                     u32 function, void *handler_context, void **return_context)
 463 {
 464         /*
 465          * The EC object is in the handler context and is needed
 466          * when calling the acpi_ec_space_handler.
 467          */
 468         *return_context = (function != ACPI_REGION_DEACTIVATE) ?
 469             handler_context : NULL;
 470
 471         return AE_OK;
 472 }
 473
 474 static acpi_status
 475 acpi_ec_space_handler(u32 function,
 476                       acpi_physical_address address,
 477                       u32 bit_width,
 478                       acpi_integer * value,
 479                       void *handler_context, void *region_context)
 480 {
 481         int result = 0;
 482         struct acpi_ec *ec = NULL;
 483         u64 temp = *value;
 484         acpi_integer f_v = 0;
 485         int i = 0;
 486
 487         if ((address > 0xFF) || !value || !handler_context)
 488                 return AE_BAD_PARAMETER;
 489
 490         if (bit_width != 8 && acpi_strict) {
 491                 return AE_BAD_PARAMETER;
 492         }
 493
 494         ec = (struct acpi_ec *)handler_context;
 495
 496       next_byte:
 497         switch (function) {
 498         case ACPI_READ:
 499                 temp = 0;
 500                 result = acpi_ec_read(ec, (u8) address, (u8 *) & temp);
 501                 break;
 502         case ACPI_WRITE:
 503                 result = acpi_ec_write(ec, (u8) address, (u8) temp);
 504                 break;
 505         default:
 506                 result = -EINVAL;
 507                 goto out;
 508                 break;
 509         }
 510
 511         bit_width -= 8;
 512         if (bit_width) {
 513                 if (function == ACPI_READ)
 514                         f_v |= temp << 8 * i;
 515                 if (function == ACPI_WRITE)
 516                         temp >>= 8;
 517                 i++;
 518                 address++;
 519                 goto next_byte;
 520         }
 521
 522         if (function == ACPI_READ) {
 523                 f_v |= temp << 8 * i;
 524                 *value = f_v;
 525         }
 526
 527       out:
 528         switch (result) {
 529         case -EINVAL:
 530                 return AE_BAD_PARAMETER;
 531                 break;
 532         case -ENODEV:
 533                 return AE_NOT_FOUND;
 534                 break;
 535         case -ETIME:
 536                 return AE_TIME;
 537                 break;
 538         default:
 539                 return AE_OK;
 540         }
 541 }
 542
 543 /* --------------------------------------------------------------------------
 544                               FS Interface (/proc)
 545    -------------------------------------------------------------------------- */
 546
 547 static struct proc_dir_entry *acpi_ec_dir;
 548
 549 static int acpi_ec_read_info(struct seq_file *seq, void *offset)
 550 {
 551         struct acpi_ec *ec = (struct acpi_ec *)seq->private;
 552
 553         if (!ec)
 554                 goto end;
 555
 556         seq_printf(seq, "gpe:                 0x%02x\n", (u32) ec->gpe);
 557         seq_printf(seq, "ports:                   0x%02x, 0x%02x\n",
 558                    (u32) ec->command_addr, (u32) ec->data_addr);
 559         seq_printf(seq, "use global lock:         %s\n",
 560                    ec->global_lock ? "yes" : "no");
 561         acpi_enable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
 562
 563       end:
 564         return 0;
 565 }
 566
 567 static int acpi_ec_info_open_fs(struct inode *inode, struct file *file)
 568 {
 569         return single_open(file, acpi_ec_read_info, PDE(inode)->data);
 570 }
 571
 572 static struct file_operations acpi_ec_info_ops = {
 573         .open = acpi_ec_info_open_fs,
 574         .read = seq_read,
 575         .llseek = seq_lseek,
 576         .release = single_release,
 577         .owner = THIS_MODULE,
 578 };
 579
 580 static int acpi_ec_add_fs(struct acpi_device *device)
 581 {
 582         struct proc_dir_entry *entry = NULL;
 583
 584         if (!acpi_device_dir(device)) {
 585                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
 586                                                      acpi_ec_dir);
 587                 if (!acpi_device_dir(device))
 588                         return -ENODEV;
 589         }
 590
 591         entry = create_proc_entry(ACPI_EC_FILE_INFO, S_IRUGO,
 592                                   acpi_device_dir(device));
 593         if (!entry)
 594                 return -ENODEV;
 595         else {
 596                 entry->proc_fops = &acpi_ec_info_ops;
 597                 entry->data = acpi_driver_data(device);
 598                 entry->owner = THIS_MODULE;
 599         }
 600
 601         return 0;
 602 }
 603
 604 static int acpi_ec_remove_fs(struct acpi_device *device)
 605 {
 606
 607         if (acpi_device_dir(device)) {
 608                 remove_proc_entry(ACPI_EC_FILE_INFO, acpi_device_dir(device));
 609                 remove_proc_entry(acpi_device_bid(device), acpi_ec_dir);
 610                 acpi_device_dir(device) = NULL;
 611         }
 612
 613         return 0;
 614 }
 615
 616 /* --------------------------------------------------------------------------
 617                                Driver Interface
 618    -------------------------------------------------------------------------- */
 619
 620 static int acpi_ec_add(struct acpi_device *device)
 621 {
 622         int result = 0;
 623         acpi_status status = AE_OK;
 624         struct acpi_ec *ec = NULL;
 625
 626         if (!device)
 627                 return -EINVAL;
 628
 629         ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
 630         if (!ec)
 631                 return -ENOMEM;
 632
 633         ec->handle = device->handle;
 634         ec->uid = -1;
 635         mutex_init(&ec->lock);
 636         atomic_set(&ec->query_pending, 0);
 637         if (acpi_ec_mode == EC_INTR) {
 638                 atomic_set(&ec->leaving_burst, 1);
 639                 init_waitqueue_head(&ec->wait);
 640         }
 641         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
 642         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
 643         acpi_driver_data(device) = ec;
 644
 645         /* Use the global lock for all EC transactions? */
 646         acpi_evaluate_integer(ec->handle, "_GLK", NULL, &ec->global_lock);
 647
 648         /* XXX we don't test uids, because on some boxes ecdt uid = 0, see:
 649            http://bugzilla.kernel.org/show_bug.cgi?id=6111 */
 650         if (ec_ecdt) {
 651                 acpi_remove_address_space_handler(ACPI_ROOT_OBJECT,
 652                                                   ACPI_ADR_SPACE_EC,
 653                                                   &acpi_ec_space_handler);
 654
 655                 acpi_remove_gpe_handler(NULL, ec_ecdt->gpe,
 656                                         &acpi_ec_gpe_handler);
 657
 658                 kfree(ec_ecdt);
 659         }
 660
 661         /* Get GPE bit assignment (EC events). */
 662         /* TODO: Add support for _GPE returning a package */
 663         status = acpi_evaluate_integer(ec->handle, "_GPE", NULL, &ec->gpe);
 664         if (ACPI_FAILURE(status)) {
 665                 ACPI_EXCEPTION((AE_INFO, status,
 666                                 "Obtaining GPE bit assignment"));
 667                 result = -ENODEV;
 668                 goto end;
 669         }
 670
 671         result = acpi_ec_add_fs(device);
 672         if (result)
 673                 goto end;
 674
 675         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "%s [%s] (gpe %d) interrupt mode.",
 676                           acpi_device_name(device), acpi_device_bid(device),
 677                           (u32) ec->gpe));
 678
 679         if (!first_ec)
 680                 first_ec = device;
 681
 682       end:
 683         if (result)
 684                 kfree(ec);
 685
 686         return result;
 687 }
 688
 689 static int acpi_ec_remove(struct acpi_device *device, int type)
 690 {
 691         struct acpi_ec *ec = NULL;
 692
 693         if (!device)
 694                 return -EINVAL;
 695
 696         ec = acpi_driver_data(device);
 697
 698         acpi_ec_remove_fs(device);
 699
 700         kfree(ec);
 701
 702         return 0;
 703 }
 704
 705 static acpi_status
 706 acpi_ec_io_ports(struct acpi_resource *resource, void *context)
 707 {
 708         struct acpi_ec *ec = (struct acpi_ec *)context;
 709
 710         if (resource->type != ACPI_RESOURCE_TYPE_IO) {
 711                 return AE_OK;
 712         }
 713
 714         /*
 715          * The first address region returned is the data port, and
 716          * the second address region returned is the status/command
 717          * port.
 718          */
 719         if (ec->data_addr == 0) {
 720                 ec->data_addr = resource->data.io.minimum;
 721         } else if (ec->command_addr == 0) {
 722                 ec->command_addr = resource->data.io.minimum;
 723         } else {
 724                 return AE_CTRL_TERMINATE;
 725         }
 726
 727         return AE_OK;
 728 }
 729
 730 static int acpi_ec_start(struct acpi_device *device)
 731 {
 732         acpi_status status = AE_OK;
 733         struct acpi_ec *ec = NULL;
 734
 735         if (!device)
 736                 return -EINVAL;
 737
 738         ec = acpi_driver_data(device);
 739
 740         if (!ec)
 741                 return -EINVAL;
 742
 743         /*
 744          * Get I/O port addresses. Convert to GAS format.
 745          */
 746         status = acpi_walk_resources(ec->handle, METHOD_NAME__CRS,
 747                                      acpi_ec_io_ports, ec);
 748         if (ACPI_FAILURE(status) || ec->command_addr == 0) {
 749                 ACPI_EXCEPTION((AE_INFO, status,
 750                                 "Error getting I/O port addresses"));
 751                 return -ENODEV;
 752         }
 753
 754         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "gpe=0x%02lx, ports=0x%2lx,0x%2lx",
 755                           ec->gpe, ec->command_addr, ec->data_addr));
 756
 757         /*
 758          * Install GPE handler
 759          */
 760         status = acpi_install_gpe_handler(NULL, ec->gpe,
 761                                           ACPI_GPE_EDGE_TRIGGERED,
 762                                           &acpi_ec_gpe_handler, ec);
 763         if (ACPI_FAILURE(status)) {
 764                 return -ENODEV;
 765         }
 766         acpi_set_gpe_type(NULL, ec->gpe, ACPI_GPE_TYPE_RUNTIME);
 767         acpi_enable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
 768
 769         status = acpi_install_address_space_handler(ec->handle,
 770                                                     ACPI_ADR_SPACE_EC,
 771                                                     &acpi_ec_space_handler,
 772                                                     &acpi_ec_space_setup, ec);
 773         if (ACPI_FAILURE(status)) {
 774                 acpi_remove_gpe_handler(NULL, ec->gpe, &acpi_ec_gpe_handler);
 775                 return -ENODEV;
 776         }
 777
 778         return AE_OK;
 779 }
 780
 781 static int acpi_ec_stop(struct acpi_device *device, int type)
 782 {
 783         acpi_status status = AE_OK;
 784         struct acpi_ec *ec = NULL;
 785
 786         if (!device)
 787                 return -EINVAL;
 788
 789         ec = acpi_driver_data(device);
 790
 791         status = acpi_remove_address_space_handler(ec->handle,
 792                                                    ACPI_ADR_SPACE_EC,
 793                                                    &acpi_ec_space_handler);
 794         if (ACPI_FAILURE(status))
 795                 return -ENODEV;
 796
 797         status = acpi_remove_gpe_handler(NULL, ec->gpe, &acpi_ec_gpe_handler);
 798         if (ACPI_FAILURE(status))
 799                 return -ENODEV;
 800
 801         return 0;
 802 }
 803
 804 static acpi_status __init
 805 acpi_fake_ecdt_callback(acpi_handle handle,
 806                         u32 Level, void *context, void **retval)
 807 {
 808         acpi_status status;
 809
 810         mutex_init(&ec_ecdt->lock);
 811         if (acpi_ec_mode == EC_INTR) {
 812                 init_waitqueue_head(&ec_ecdt->wait);
 813         }
 814         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
 815                                      acpi_ec_io_ports, ec_ecdt);
 816         if (ACPI_FAILURE(status))
 817                 return status;
 818
 819         ec_ecdt->uid = -1;
 820         acpi_evaluate_integer(handle, "_UID", NULL, &ec_ecdt->uid);
 821
 822         status = acpi_evaluate_integer(handle, "_GPE", NULL, &ec_ecdt->gpe);
 823         if (ACPI_FAILURE(status))
 824                 return status;
 825         ec_ecdt->global_lock = TRUE;
 826         ec_ecdt->handle = handle;
 827
 828         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "GPE=0x%02lx, ports=0x%2lx, 0x%2lx",
 829                           ec_ecdt->gpe, ec_ecdt->command_addr,
 830                           ec_ecdt->data_addr));
 831
 832         return AE_CTRL_TERMINATE;
 833 }
 834
 835 /*
 836  * Some BIOS (such as some from Gateway laptops) access EC region very early
 837  * such as in BAT0._INI or EC._INI before an EC device is found and
 838  * do not provide an ECDT. According to ACPI spec, ECDT isn't mandatorily
 839  * required, but if EC regison is accessed early, it is required.
 840  * The routine tries to workaround the BIOS bug by pre-scan EC device
 841  * It assumes that _CRS, _HID, _GPE, _UID methods of EC don't touch any
 842  * op region (since _REG isn't invoked yet). The assumption is true for
 843  * all systems found.
 844  */
 845 static int __init acpi_ec_fake_ecdt(void)
 846 {
 847         acpi_status status;
 848         int ret = 0;
 849
 850         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Try to make an fake ECDT"));
 851
 852         ec_ecdt = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
 853         if (!ec_ecdt) {
 854                 ret = -ENOMEM;
 855                 goto error;
 856         }
 857
 858         status = acpi_get_devices(ACPI_EC_HID,
 859                                   acpi_fake_ecdt_callback, NULL, NULL);
 860         if (ACPI_FAILURE(status)) {
 861                 kfree(ec_ecdt);
 862                 ec_ecdt = NULL;
 863                 ret = -ENODEV;
 864                 ACPI_EXCEPTION((AE_INFO, status, "Can't make an fake ECDT"));
 865                 goto error;
 866         }
 867         return 0;
 868       error:
 869         return ret;
 870 }
 871
 872 static int __init acpi_ec_get_real_ecdt(void)
 873 {
 874         acpi_status status;
 875         struct acpi_table_ecdt *ecdt_ptr;
 876
 877         status = acpi_get_table(ACPI_SIG_ECDT, 1,
 878                                 (struct acpi_table_header **)&ecdt_ptr);
 879         if (ACPI_FAILURE(status))
 880                 return -ENODEV;
 881
 882         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found ECDT"));
 883
 884         /*
 885          * Generate a temporary ec context to use until the namespace is scanned
 886          */
 887         ec_ecdt = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
 888         if (!ec_ecdt)
 889                 return -ENOMEM;
 890
 891         mutex_init(&ec_ecdt->lock);
 892         if (acpi_ec_mode == EC_INTR) {
 893                 init_waitqueue_head(&ec_ecdt->wait);
 894         }
 895         ec_ecdt->command_addr = ecdt_ptr->control.address;
 896         ec_ecdt->data_addr = ecdt_ptr->data.address;
 897         ec_ecdt->gpe = ecdt_ptr->gpe;
 898         /* use the GL just to be safe */
 899         ec_ecdt->global_lock = TRUE;
 900         ec_ecdt->uid = ecdt_ptr->uid;
 901
 902         status = acpi_get_handle(NULL, ecdt_ptr->id, &ec_ecdt->handle);
 903         if (ACPI_FAILURE(status)) {
 904                 goto error;
 905         }
 906
 907         return 0;
 908       error:
 909         ACPI_EXCEPTION((AE_INFO, status, "Could not use ECDT"));
 910         kfree(ec_ecdt);
 911         ec_ecdt = NULL;
 912
 913         return -ENODEV;
 914 }
 915
 916 static int __initdata acpi_fake_ecdt_enabled;
 917 int __init acpi_ec_ecdt_probe(void)
 918 {
 919         acpi_status status;
 920         int ret;
 921
 922         ret = acpi_ec_get_real_ecdt();
 923         /* Try to make a fake ECDT */
 924         if (ret && acpi_fake_ecdt_enabled) {
 925                 ret = acpi_ec_fake_ecdt();
 926         }
 927
 928         if (ret)
 929                 return 0;
 930
 931         /*
 932          * Install GPE handler
 933          */
 934         status = acpi_install_gpe_handler(NULL, ec_ecdt->gpe,
 935                                           ACPI_GPE_EDGE_TRIGGERED,
 936                                           &acpi_ec_gpe_handler, ec_ecdt);
 937         if (ACPI_FAILURE(status)) {
 938                 goto error;
 939         }
 940         acpi_set_gpe_type(NULL, ec_ecdt->gpe, ACPI_GPE_TYPE_RUNTIME);
 941         acpi_enable_gpe(NULL, ec_ecdt->gpe, ACPI_NOT_ISR);
 942
 943         status = acpi_install_address_space_handler(ACPI_ROOT_OBJECT,
 944                                                     ACPI_ADR_SPACE_EC,
 945                                                     &acpi_ec_space_handler,
 946                                                     &acpi_ec_space_setup,
 947                                                     ec_ecdt);
 948         if (ACPI_FAILURE(status)) {
 949                 acpi_remove_gpe_handler(NULL, ec_ecdt->gpe,
 950                                         &acpi_ec_gpe_handler);
 951                 goto error;
 952         }
 953
 954         return 0;
 955
 956       error:
 957         ACPI_EXCEPTION((AE_INFO, status, "Could not use ECDT"));
 958         kfree(ec_ecdt);
 959         ec_ecdt = NULL;
 960
 961         return -ENODEV;
 962 }
 963
 964 static int __init acpi_ec_init(void)
 965 {
 966         int result = 0;
 967
 968         if (acpi_disabled)
 969                 return 0;
 970
 971         acpi_ec_dir = proc_mkdir(ACPI_EC_CLASS, acpi_root_dir);
 972         if (!acpi_ec_dir)
 973                 return -ENODEV;
 974
 975         /* Now register the driver for the EC */
 976         result = acpi_bus_register_driver(&acpi_ec_driver);
 977         if (result < 0) {
 978                 remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
 979                 return -ENODEV;
 980         }
 981
 982         return result;
 983 }
 984
 985 subsys_initcall(acpi_ec_init);
 986
 987 /* EC driver currently not unloadable */
 988 #if 0
 989 static void __exit acpi_ec_exit(void)
 990 {
 991
 992         acpi_bus_unregister_driver(&acpi_ec_driver);
 993
 994         remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
 995
 996         return;
 997 }
 998 #endif                          /* 0 */
 999
1000 static int __init acpi_fake_ecdt_setup(char *str)
1001 {
1002         acpi_fake_ecdt_enabled = 1;
1003         return 1;
1004 }
1005
1006 __setup("acpi_fake_ecdt", acpi_fake_ecdt_setup);
1007 static int __init acpi_ec_set_intr_mode(char *str)
1008 {
1009         int intr;
1010
1011         if (!get_option(&str, &intr))
1012                 return 0;
1013
1014         if (intr) {
1015                 acpi_ec_mode = EC_INTR;
1016         } else {
1017                 acpi_ec_mode = EC_POLL;
1018         }
1019         acpi_ec_driver.ops.add = acpi_ec_add;
1020         printk(KERN_NOTICE PREFIX "%s mode.\n",
1021                           intr ? "interrupt" : "polling");
1022
1023         return 1;
1024 }
1025
1026 __setup("ec_intr=", acpi_ec_set_intr_mode);