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("ec");
  42 #define ACPI_EC_COMPONENT               0x00100000
  43 #define ACPI_EC_CLASS                   "embedded_controller"
  44 #define ACPI_EC_HID                     "PNP0C09"
  45 #define ACPI_EC_DEVICE_NAME             "Embedded Controller"
  46 #define ACPI_EC_FILE_INFO               "info"
  47 #undef PREFIX
  48 #define PREFIX                          "ACPI: EC: "
  49 /* EC status register */
  50 #define ACPI_EC_FLAG_OBF        0x01    /* Output buffer full */
  51 #define ACPI_EC_FLAG_IBF        0x02    /* Input buffer full */
  52 #define ACPI_EC_FLAG_BURST      0x10    /* burst mode */
  53 #define ACPI_EC_FLAG_SCI        0x20    /* EC-SCI occurred */
  54 /* EC commands */
  55 enum ec_command {
  56         ACPI_EC_COMMAND_READ = 0x80,
  57         ACPI_EC_COMMAND_WRITE = 0x81,
  58         ACPI_EC_BURST_ENABLE = 0x82,
  59         ACPI_EC_BURST_DISABLE = 0x83,
  60         ACPI_EC_COMMAND_QUERY = 0x84,
  61 };
  62 /* EC events */
  63 enum ec_event {
  64         ACPI_EC_EVENT_OBF_1 = 1,        /* Output buffer full */
  65         ACPI_EC_EVENT_IBF_0,    /* Input buffer empty */
  66 };
  67
  68 #define ACPI_EC_DELAY           500     /* Wait 500ms max. during EC ops */
  69 #define ACPI_EC_UDELAY_GLK      1000    /* Wait 1ms max. to get global lock */
  70
  71 static enum ec_mode {
  72         EC_INTR = 1,            /* Output buffer full */
  73         EC_POLL,                /* Input buffer empty */
  74 } acpi_ec_mode = EC_INTR;
  75
  76 static int acpi_ec_remove(struct acpi_device *device, int type);
  77 static int acpi_ec_start(struct acpi_device *device);
  78 static int acpi_ec_stop(struct acpi_device *device, int type);
  79 static int acpi_ec_add(struct acpi_device *device);
  80
  81 static struct acpi_driver acpi_ec_driver = {
  82         .name = "ec",
  83         .class = ACPI_EC_CLASS,
  84         .ids = ACPI_EC_HID,
  85         .ops = {
  86                 .add = acpi_ec_add,
  87                 .remove = acpi_ec_remove,
  88                 .start = acpi_ec_start,
  89                 .stop = acpi_ec_stop,
  90                 },
  91 };
  92
  93 /* If we find an EC via the ECDT, we need to keep a ptr to its context */
  94 /* External interfaces use first EC only, so remember */
  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 event_count;
 105         wait_queue_head_t wait;
 106 } *boot_ec, *first_ec;
 107
 108 /* --------------------------------------------------------------------------
 109                              Transaction Management
 110    -------------------------------------------------------------------------- */
 111
 112 static inline u8 acpi_ec_read_status(struct acpi_ec *ec)
 113 {
 114         return inb(ec->command_addr);
 115 }
 116
 117 static inline u8 acpi_ec_read_data(struct acpi_ec *ec)
 118 {
 119         return inb(ec->data_addr);
 120 }
 121
 122 static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command)
 123 {
 124         outb(command, ec->command_addr);
 125 }
 126
 127 static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data)
 128 {
 129         outb(data, ec->data_addr);
 130 }
 131
 132 static inline int acpi_ec_check_status(struct acpi_ec *ec, enum ec_event event,
 133                                        unsigned old_count)
 134 {
 135         u8 status = acpi_ec_read_status(ec);
 136         if (old_count == atomic_read(&ec->event_count))
 137                 return 0;
 138         if (event == ACPI_EC_EVENT_OBF_1) {
 139                 if (status & ACPI_EC_FLAG_OBF)
 140                         return 1;
 141         } else if (event == ACPI_EC_EVENT_IBF_0) {
 142                 if (!(status & ACPI_EC_FLAG_IBF))
 143                         return 1;
 144         }
 145
 146         return 0;
 147 }
 148
 149 static int acpi_ec_wait(struct acpi_ec *ec, enum ec_event event, unsigned count)
 150 {
 151         if (acpi_ec_mode == EC_POLL) {
 152                 unsigned long delay = jiffies + msecs_to_jiffies(ACPI_EC_DELAY);
 153                 while (time_before(jiffies, delay)) {
 154                         if (acpi_ec_check_status(ec, event, 0))
 155                                 return 0;
 156                 }
 157         } else {
 158                 if (wait_event_timeout(ec->wait,
 159                                        acpi_ec_check_status(ec, event, count),
 160                                        msecs_to_jiffies(ACPI_EC_DELAY)) ||
 161                     acpi_ec_check_status(ec, event, 0)) {
 162                         return 0;
 163                 } else {
 164                         printk(KERN_ERR PREFIX "acpi_ec_wait timeout,"
 165                                " status = %d, expect_event = %d\n",
 166                                acpi_ec_read_status(ec), event);
 167                 }
 168         }
 169
 170         return -ETIME;
 171 }
 172
 173 static int acpi_ec_transaction_unlocked(struct acpi_ec *ec, u8 command,
 174                                         const u8 * wdata, unsigned wdata_len,
 175                                         u8 * rdata, unsigned rdata_len)
 176 {
 177         int result = 0;
 178         unsigned count = atomic_read(&ec->event_count);
 179         acpi_ec_write_cmd(ec, command);
 180
 181         for (; wdata_len > 0; --wdata_len) {
 182                 result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0, count);
 183                 if (result) {
 184                         printk(KERN_ERR PREFIX
 185                                "write_cmd timeout, command = %d\n", command);
 186                         goto end;
 187                 }
 188                 count = atomic_read(&ec->event_count);
 189                 acpi_ec_write_data(ec, *(wdata++));
 190         }
 191
 192         if (!rdata_len) {
 193                 result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0, count);
 194                 if (result) {
 195                         printk(KERN_ERR PREFIX
 196                                "finish-write timeout, command = %d\n", command);
 197                         goto end;
 198                 }
 199         } else if (command == ACPI_EC_COMMAND_QUERY) {
 200                 atomic_set(&ec->query_pending, 0);
 201         }
 202
 203         for (; rdata_len > 0; --rdata_len) {
 204                 result = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF_1, count);
 205                 if (result) {
 206                         printk(KERN_ERR PREFIX "read timeout, command = %d\n",
 207                                command);
 208                         goto end;
 209                 }
 210                 count = atomic_read(&ec->event_count);
 211                 *(rdata++) = acpi_ec_read_data(ec);
 212         }
 213       end:
 214         return result;
 215 }
 216
 217 static int acpi_ec_transaction(struct acpi_ec *ec, u8 command,
 218                                const u8 * wdata, unsigned wdata_len,
 219                                u8 * rdata, unsigned rdata_len)
 220 {
 221         int status;
 222         u32 glk;
 223
 224         if (!ec || (wdata_len && !wdata) || (rdata_len && !rdata))
 225                 return -EINVAL;
 226
 227         if (rdata)
 228                 memset(rdata, 0, rdata_len);
 229
 230         mutex_lock(&ec->lock);
 231         if (ec->global_lock) {
 232                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 233                 if (ACPI_FAILURE(status)) {
 234                         mutex_unlock(&ec->lock);
 235                         return -ENODEV;
 236                 }
 237         }
 238
 239         /* Make sure GPE is enabled before doing transaction */
 240         acpi_enable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
 241
 242         status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0, 0);
 243         if (status) {
 244                 printk(KERN_DEBUG PREFIX
 245                        "input buffer is not empty, aborting transaction\n");
 246                 goto end;
 247         }
 248
 249         status = acpi_ec_transaction_unlocked(ec, command,
 250                                               wdata, wdata_len,
 251                                               rdata, rdata_len);
 252
 253       end:
 254
 255         if (ec->global_lock)
 256                 acpi_release_global_lock(glk);
 257         mutex_unlock(&ec->lock);
 258
 259         return status;
 260 }
 261
 262 /*
 263  * Note: samsung nv5000 doesn't work with ec burst mode.
 264  * http://bugzilla.kernel.org/show_bug.cgi?id=4980
 265  */
 266 int acpi_ec_burst_enable(struct acpi_ec *ec)
 267 {
 268         u8 d;
 269         return acpi_ec_transaction(ec, ACPI_EC_BURST_ENABLE, NULL, 0, &d, 1);
 270 }
 271
 272 int acpi_ec_burst_disable(struct acpi_ec *ec)
 273 {
 274         return acpi_ec_transaction(ec, ACPI_EC_BURST_DISABLE, NULL, 0, NULL, 0);
 275 }
 276
 277 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 * data)
 278 {
 279         int result;
 280         u8 d;
 281
 282         result = acpi_ec_transaction(ec, ACPI_EC_COMMAND_READ,
 283                                      &address, 1, &d, 1);
 284         *data = d;
 285         return result;
 286 }
 287
 288 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
 289 {
 290         u8 wdata[2] = { address, data };
 291         return acpi_ec_transaction(ec, ACPI_EC_COMMAND_WRITE,
 292                                    wdata, 2, NULL, 0);
 293 }
 294
 295 /*
 296  * Externally callable EC access functions. For now, assume 1 EC only
 297  */
 298 int ec_burst_enable(void)
 299 {
 300         if (!first_ec)
 301                 return -ENODEV;
 302         return acpi_ec_burst_enable(first_ec);
 303 }
 304
 305 EXPORT_SYMBOL(ec_burst_enable);
 306
 307 int ec_burst_disable(void)
 308 {
 309         if (!first_ec)
 310                 return -ENODEV;
 311         return acpi_ec_burst_disable(first_ec);
 312 }
 313
 314 EXPORT_SYMBOL(ec_burst_disable);
 315
 316 int ec_read(u8 addr, u8 * val)
 317 {
 318         int err;
 319         u8 temp_data;
 320
 321         if (!first_ec)
 322                 return -ENODEV;
 323
 324         err = acpi_ec_read(first_ec, addr, &temp_data);
 325
 326         if (!err) {
 327                 *val = temp_data;
 328                 return 0;
 329         } else
 330                 return err;
 331 }
 332
 333 EXPORT_SYMBOL(ec_read);
 334
 335 int ec_write(u8 addr, u8 val)
 336 {
 337         int err;
 338
 339         if (!first_ec)
 340                 return -ENODEV;
 341
 342         err = acpi_ec_write(first_ec, addr, val);
 343
 344         return err;
 345 }
 346
 347 EXPORT_SYMBOL(ec_write);
 348
 349 int ec_transaction(u8 command,
 350                    const u8 * wdata, unsigned wdata_len,
 351                    u8 * rdata, unsigned rdata_len)
 352 {
 353         if (!first_ec)
 354                 return -ENODEV;
 355
 356         return acpi_ec_transaction(first_ec, command, wdata,
 357                                    wdata_len, rdata, rdata_len);
 358 }
 359
 360 EXPORT_SYMBOL(ec_transaction);
 361
 362 static int acpi_ec_query(struct acpi_ec *ec, u8 * data)
 363 {
 364         int result;
 365         u8 d;
 366
 367         if (!ec || !data)
 368                 return -EINVAL;
 369
 370         /*
 371          * Query the EC to find out which _Qxx method we need to evaluate.
 372          * Note that successful completion of the query causes the ACPI_EC_SCI
 373          * bit to be cleared (and thus clearing the interrupt source).
 374          */
 375
 376         result = acpi_ec_transaction(ec, ACPI_EC_COMMAND_QUERY, NULL, 0, &d, 1);
 377         if (result)
 378                 return result;
 379
 380         if (!d)
 381                 return -ENODATA;
 382
 383         *data = d;
 384         return 0;
 385 }
 386
 387 /* --------------------------------------------------------------------------
 388                                 Event Management
 389    -------------------------------------------------------------------------- */
 390
 391 static void acpi_ec_gpe_query(void *ec_cxt)
 392 {
 393         struct acpi_ec *ec = ec_cxt;
 394         u8 value = 0;
 395         char object_name[8];
 396
 397         if (!ec || acpi_ec_query(ec, &value))
 398                 return;
 399
 400         snprintf(object_name, 8, "_Q%2.2X", value);
 401
 402         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Evaluating %s", object_name));
 403
 404         acpi_evaluate_object(ec->handle, object_name, NULL, NULL);
 405 }
 406
 407 static u32 acpi_ec_gpe_handler(void *data)
 408 {
 409         acpi_status status = AE_OK;
 410         u8 value;
 411         struct acpi_ec *ec = data;
 412         atomic_inc(&ec->event_count);
 413
 414         if (acpi_ec_mode == EC_INTR) {
 415                 wake_up(&ec->wait);
 416         }
 417
 418         value = acpi_ec_read_status(ec);
 419         if ((value & ACPI_EC_FLAG_SCI) && !atomic_read(&ec->query_pending)) {
 420                 atomic_set(&ec->query_pending, 1);
 421                 status =
 422                     acpi_os_execute(OSL_EC_BURST_HANDLER, acpi_ec_gpe_query,
 423                                     ec);
 424         }
 425
 426         return status == AE_OK ?
 427             ACPI_INTERRUPT_HANDLED : ACPI_INTERRUPT_NOT_HANDLED;
 428 }
 429
 430 /* --------------------------------------------------------------------------
 431                              Address Space Management
 432    -------------------------------------------------------------------------- */
 433
 434 static acpi_status
 435 acpi_ec_space_setup(acpi_handle region_handle,
 436                     u32 function, void *handler_context, void **return_context)
 437 {
 438         /*
 439          * The EC object is in the handler context and is needed
 440          * when calling the acpi_ec_space_handler.
 441          */
 442         *return_context = (function != ACPI_REGION_DEACTIVATE) ?
 443             handler_context : NULL;
 444
 445         return AE_OK;
 446 }
 447
 448 static acpi_status
 449 acpi_ec_space_handler(u32 function,
 450                       acpi_physical_address address,
 451                       u32 bit_width,
 452                       acpi_integer * value,
 453                       void *handler_context, void *region_context)
 454 {
 455         int result = 0;
 456         struct acpi_ec *ec = handler_context;
 457         u64 temp = *value;
 458         acpi_integer f_v = 0;
 459         int i = 0;
 460
 461         if ((address > 0xFF) || !value || !handler_context)
 462                 return AE_BAD_PARAMETER;
 463
 464         if (bit_width != 8 && acpi_strict) {
 465                 return AE_BAD_PARAMETER;
 466         }
 467
 468       next_byte:
 469         switch (function) {
 470         case ACPI_READ:
 471                 temp = 0;
 472                 result = acpi_ec_read(ec, (u8) address, (u8 *) & temp);
 473                 break;
 474         case ACPI_WRITE:
 475                 result = acpi_ec_write(ec, (u8) address, (u8) temp);
 476                 break;
 477         default:
 478                 result = -EINVAL;
 479                 goto out;
 480                 break;
 481         }
 482
 483         bit_width -= 8;
 484         if (bit_width) {
 485                 if (function == ACPI_READ)
 486                         f_v |= temp << 8 * i;
 487                 if (function == ACPI_WRITE)
 488                         temp >>= 8;
 489                 i++;
 490                 address++;
 491                 goto next_byte;
 492         }
 493
 494         if (function == ACPI_READ) {
 495                 f_v |= temp << 8 * i;
 496                 *value = f_v;
 497         }
 498
 499       out:
 500         switch (result) {
 501         case -EINVAL:
 502                 return AE_BAD_PARAMETER;
 503                 break;
 504         case -ENODEV:
 505                 return AE_NOT_FOUND;
 506                 break;
 507         case -ETIME:
 508                 return AE_TIME;
 509                 break;
 510         default:
 511                 return AE_OK;
 512         }
 513 }
 514
 515 /* --------------------------------------------------------------------------
 516                               FS Interface (/proc)
 517    -------------------------------------------------------------------------- */
 518
 519 static struct proc_dir_entry *acpi_ec_dir;
 520
 521 static int acpi_ec_read_info(struct seq_file *seq, void *offset)
 522 {
 523         struct acpi_ec *ec = seq->private;
 524
 525         if (!ec)
 526                 goto end;
 527
 528         seq_printf(seq, "gpe:                 0x%02x\n", (u32) ec->gpe);
 529         seq_printf(seq, "ports:                   0x%02x, 0x%02x\n",
 530                    (u32) ec->command_addr, (u32) ec->data_addr);
 531         seq_printf(seq, "use global lock:         %s\n",
 532                    ec->global_lock ? "yes" : "no");
 533         acpi_enable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
 534
 535       end:
 536         return 0;
 537 }
 538
 539 static int acpi_ec_info_open_fs(struct inode *inode, struct file *file)
 540 {
 541         return single_open(file, acpi_ec_read_info, PDE(inode)->data);
 542 }
 543
 544 static struct file_operations acpi_ec_info_ops = {
 545         .open = acpi_ec_info_open_fs,
 546         .read = seq_read,
 547         .llseek = seq_lseek,
 548         .release = single_release,
 549         .owner = THIS_MODULE,
 550 };
 551
 552 static int acpi_ec_add_fs(struct acpi_device *device)
 553 {
 554         struct proc_dir_entry *entry = NULL;
 555
 556         if (!acpi_device_dir(device)) {
 557                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
 558                                                      acpi_ec_dir);
 559                 if (!acpi_device_dir(device))
 560                         return -ENODEV;
 561         }
 562
 563         entry = create_proc_entry(ACPI_EC_FILE_INFO, S_IRUGO,
 564                                   acpi_device_dir(device));
 565         if (!entry)
 566                 return -ENODEV;
 567         else {
 568                 entry->proc_fops = &acpi_ec_info_ops;
 569                 entry->data = acpi_driver_data(device);
 570                 entry->owner = THIS_MODULE;
 571         }
 572
 573         return 0;
 574 }
 575
 576 static int acpi_ec_remove_fs(struct acpi_device *device)
 577 {
 578
 579         if (acpi_device_dir(device)) {
 580                 remove_proc_entry(ACPI_EC_FILE_INFO, acpi_device_dir(device));
 581                 remove_proc_entry(acpi_device_bid(device), acpi_ec_dir);
 582                 acpi_device_dir(device) = NULL;
 583         }
 584
 585         return 0;
 586 }
 587
 588 /* --------------------------------------------------------------------------
 589                                Driver Interface
 590    -------------------------------------------------------------------------- */
 591 static acpi_status
 592 ec_parse_io_ports(struct acpi_resource *resource, void *context);
 593
 594 static acpi_status
 595 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval);
 596
 597 static struct acpi_ec *make_acpi_ec(void)
 598 {
 599         struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
 600         if (!ec)
 601                 return NULL;
 602
 603         atomic_set(&ec->query_pending, 0);
 604         atomic_set(&ec->event_count, 1);
 605         mutex_init(&ec->lock);
 606         init_waitqueue_head(&ec->wait);
 607
 608         return ec;
 609 }
 610
 611 static int acpi_ec_add(struct acpi_device *device)
 612 {
 613         acpi_status status = AE_OK;
 614         struct acpi_ec *ec = NULL;
 615
 616         if (!device)
 617                 return -EINVAL;
 618
 619         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
 620         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
 621
 622         ec = make_acpi_ec();
 623         if (!ec)
 624                 return -ENOMEM;
 625
 626         status = ec_parse_device(device->handle, 0, ec, NULL);
 627         if (status != AE_CTRL_TERMINATE) {
 628                 kfree(ec);
 629                 return -EINVAL;
 630         }
 631
 632         /* Check if we found the boot EC */
 633         if (boot_ec) {
 634                 if (boot_ec->gpe == ec->gpe) {
 635                         /* We might have incorrect info for GL at boot time */
 636                         mutex_lock(&boot_ec->lock);
 637                         boot_ec->global_lock = ec->global_lock;
 638                         mutex_unlock(&boot_ec->lock);
 639                         kfree(ec);
 640                         ec = boot_ec;
 641                 }
 642         } else
 643                 first_ec = ec;
 644         ec->handle = device->handle;
 645         acpi_driver_data(device) = ec;
 646
 647         acpi_ec_add_fs(device);
 648
 649         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "%s [%s] (gpe %d) interrupt mode.",
 650                           acpi_device_name(device), acpi_device_bid(device),
 651                           (u32) ec->gpe));
 652
 653         return 0;
 654 }
 655
 656 static int acpi_ec_remove(struct acpi_device *device, int type)
 657 {
 658         struct acpi_ec *ec = NULL;
 659
 660         if (!device)
 661                 return -EINVAL;
 662
 663         ec = acpi_driver_data(device);
 664
 665         acpi_ec_remove_fs(device);
 666
 667         acpi_driver_data(device) = NULL;
 668         if (ec == first_ec)
 669                 first_ec = NULL;
 670
 671         /* Don't touch boot EC */
 672         if (boot_ec != ec)
 673                 kfree(ec);
 674
 675         return 0;
 676 }
 677
 678 static acpi_status
 679 ec_parse_io_ports(struct acpi_resource *resource, void *context)
 680 {
 681         struct acpi_ec *ec = context;
 682
 683         if (resource->type != ACPI_RESOURCE_TYPE_IO) {
 684                 return AE_OK;
 685         }
 686
 687         /*
 688          * The first address region returned is the data port, and
 689          * the second address region returned is the status/command
 690          * port.
 691          */
 692         if (ec->data_addr == 0) {
 693                 ec->data_addr = resource->data.io.minimum;
 694         } else if (ec->command_addr == 0) {
 695                 ec->command_addr = resource->data.io.minimum;
 696         } else {
 697                 return AE_CTRL_TERMINATE;
 698         }
 699
 700         return AE_OK;
 701 }
 702
 703 static int ec_install_handlers(struct acpi_ec *ec)
 704 {
 705         acpi_status status;
 706         status = acpi_install_gpe_handler(NULL, ec->gpe,
 707                                           ACPI_GPE_EDGE_TRIGGERED,
 708                                           &acpi_ec_gpe_handler, ec);
 709         if (ACPI_FAILURE(status))
 710                 return -ENODEV;
 711         acpi_set_gpe_type(NULL, ec->gpe, ACPI_GPE_TYPE_RUNTIME);
 712         acpi_enable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
 713
 714         status = acpi_install_address_space_handler(ec->handle,
 715                                                     ACPI_ADR_SPACE_EC,
 716                                                     &acpi_ec_space_handler,
 717                                                     &acpi_ec_space_setup, ec);
 718         if (ACPI_FAILURE(status)) {
 719                 acpi_remove_gpe_handler(NULL, ec->gpe, &acpi_ec_gpe_handler);
 720                 return -ENODEV;
 721         }
 722
 723         return 0;
 724 }
 725
 726 static int acpi_ec_start(struct acpi_device *device)
 727 {
 728         struct acpi_ec *ec;
 729
 730         if (!device)
 731                 return -EINVAL;
 732
 733         ec = acpi_driver_data(device);
 734
 735         if (!ec)
 736                 return -EINVAL;
 737
 738         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "gpe=0x%02lx, ports=0x%2lx,0x%2lx",
 739                           ec->gpe, ec->command_addr, ec->data_addr));
 740
 741         /* Boot EC is already working */
 742         if (ec == boot_ec)
 743                 return 0;
 744
 745         return ec_install_handlers(ec);
 746 }
 747
 748 static int acpi_ec_stop(struct acpi_device *device, int type)
 749 {
 750         acpi_status status;
 751         struct acpi_ec *ec;
 752
 753         if (!device)
 754                 return -EINVAL;
 755
 756         ec = acpi_driver_data(device);
 757         if (!ec)
 758                 return -EINVAL;
 759
 760         /* Don't touch boot EC */
 761         if (ec == boot_ec)
 762                 return 0;
 763
 764         status = acpi_remove_address_space_handler(ec->handle,
 765                                                    ACPI_ADR_SPACE_EC,
 766                                                    &acpi_ec_space_handler);
 767         if (ACPI_FAILURE(status))
 768                 return -ENODEV;
 769
 770         status = acpi_remove_gpe_handler(NULL, ec->gpe, &acpi_ec_gpe_handler);
 771         if (ACPI_FAILURE(status))
 772                 return -ENODEV;
 773
 774         return 0;
 775 }
 776
 777 static acpi_status
 778 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
 779 {
 780         acpi_status status;
 781
 782         struct acpi_ec *ec = context;
 783         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
 784                                      ec_parse_io_ports, ec);
 785         if (ACPI_FAILURE(status))
 786                 return status;
 787
 788         /* Get GPE bit assignment (EC events). */
 789         /* TODO: Add support for _GPE returning a package */
 790         status = acpi_evaluate_integer(handle, "_GPE", NULL, &ec->gpe);
 791         if (ACPI_FAILURE(status))
 792                 return status;
 793
 794         /* Use the global lock for all EC transactions? */
 795         acpi_evaluate_integer(handle, "_GLK", NULL, &ec->global_lock);
 796
 797         ec->handle = handle;
 798
 799         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "GPE=0x%02lx, ports=0x%2lx, 0x%2lx",
 800                           ec->gpe, ec->command_addr, ec->data_addr));
 801
 802         return AE_CTRL_TERMINATE;
 803 }
 804
 805 int __init acpi_ec_ecdt_probe(void)
 806 {
 807         int ret;
 808         acpi_status status;
 809         struct acpi_table_ecdt *ecdt_ptr;
 810
 811         boot_ec = make_acpi_ec();
 812         if (!boot_ec)
 813                 return -ENOMEM;
 814         /*
 815          * Generate a boot ec context
 816          */
 817
 818         status = acpi_get_table(ACPI_SIG_ECDT, 1,
 819                                 (struct acpi_table_header **)&ecdt_ptr);
 820         if (ACPI_FAILURE(status))
 821                 goto error;
 822
 823         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found ECDT"));
 824
 825         boot_ec->command_addr = ecdt_ptr->control.address;
 826         boot_ec->data_addr = ecdt_ptr->data.address;
 827         boot_ec->gpe = ecdt_ptr->gpe;
 828         boot_ec->uid = ecdt_ptr->uid;
 829         boot_ec->handle = ACPI_ROOT_OBJECT;
 830
 831         ret = ec_install_handlers(boot_ec);
 832         if (!ret) {
 833                 first_ec = boot_ec;
 834                 return 0;
 835         }
 836       error:
 837         kfree(boot_ec);
 838         boot_ec = NULL;
 839
 840         return -ENODEV;
 841 }
 842
 843 static int __init acpi_ec_init(void)
 844 {
 845         int result = 0;
 846
 847         if (acpi_disabled)
 848                 return 0;
 849
 850         acpi_ec_dir = proc_mkdir(ACPI_EC_CLASS, acpi_root_dir);
 851         if (!acpi_ec_dir)
 852                 return -ENODEV;
 853
 854         /* Now register the driver for the EC */
 855         result = acpi_bus_register_driver(&acpi_ec_driver);
 856         if (result < 0) {
 857                 remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
 858                 return -ENODEV;
 859         }
 860
 861         return result;
 862 }
 863
 864 subsys_initcall(acpi_ec_init);
 865
 866 /* EC driver currently not unloadable */
 867 #if 0
 868 static void __exit acpi_ec_exit(void)
 869 {
 870
 871         acpi_bus_unregister_driver(&acpi_ec_driver);
 872
 873         remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
 874
 875         return;
 876 }
 877 #endif                          /* 0 */
 878
 879 static int __init acpi_ec_set_intr_mode(char *str)
 880 {
 881         int intr;
 882
 883         if (!get_option(&str, &intr))
 884                 return 0;
 885
 886         acpi_ec_mode = (intr) ? EC_INTR : EC_POLL;
 887
 888         printk(KERN_NOTICE PREFIX "%s mode.\n", intr ? "interrupt" : "polling");
 889
 890         return 1;
 891 }
 892
 893 __setup("ec_intr=", acpi_ec_set_intr_mode);