drivers/acpi/ec.c

   1 /*
   2  *  ec.c - ACPI Embedded Controller Driver (v2.0)
   3  *
   4  *  Copyright (C) 2006, 2007 Alexey Starikovskiy <alexey.y.starikovskiy@intel.com>
   5  *  Copyright (C) 2006 Denis Sadykov <denis.m.sadykov@intel.com>
   6  *  Copyright (C) 2004 Luming Yu <luming.yu@intel.com>
   7  *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
   8  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
   9  *
  10  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  11  *
  12  *  This program is free software; you can redistribute it and/or modify
  13  *  it under the terms of the GNU General Public License as published by
  14  *  the Free Software Foundation; either version 2 of the License, or (at
  15  *  your option) any later version.
  16  *
  17  *  This program is distributed in the hope that it will be useful, but
  18  *  WITHOUT ANY WARRANTY; without even the implied warranty of
  19  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  20  *  General Public License for more details.
  21  *
  22  *  You should have received a copy of the GNU General Public License along
  23  *  with this program; if not, write to the Free Software Foundation, Inc.,
  24  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
  25  *
  26  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  27  */
  28
  29 #include <linux/kernel.h>
  30 #include <linux/module.h>
  31 #include <linux/init.h>
  32 #include <linux/types.h>
  33 #include <linux/delay.h>
  34 #include <linux/proc_fs.h>
  35 #include <linux/seq_file.h>
  36 #include <linux/interrupt.h>
  37 #include <asm/io.h>
  38 #include <acpi/acpi_bus.h>
  39 #include <acpi/acpi_drivers.h>
  40 #include <acpi/actypes.h>
  41
  42 #define _COMPONENT              ACPI_EC_COMPONENT
  43 ACPI_MODULE_NAME("ec");
  44 #define ACPI_EC_COMPONENT               0x00100000
  45 #define ACPI_EC_CLASS                   "embedded_controller"
  46 #define ACPI_EC_HID                     "PNP0C09"
  47 #define ACPI_EC_DEVICE_NAME             "Embedded Controller"
  48 #define ACPI_EC_FILE_INFO               "info"
  49 #undef PREFIX
  50 #define PREFIX                          "ACPI: EC: "
  51 /* EC status register */
  52 #define ACPI_EC_FLAG_OBF        0x01    /* Output buffer full */
  53 #define ACPI_EC_FLAG_IBF        0x02    /* Input buffer full */
  54 #define ACPI_EC_FLAG_BURST      0x10    /* burst mode */
  55 #define ACPI_EC_FLAG_SCI        0x20    /* EC-SCI occurred */
  56 /* EC commands */
  57 enum ec_command {
  58         ACPI_EC_COMMAND_READ = 0x80,
  59         ACPI_EC_COMMAND_WRITE = 0x81,
  60         ACPI_EC_BURST_ENABLE = 0x82,
  61         ACPI_EC_BURST_DISABLE = 0x83,
  62         ACPI_EC_COMMAND_QUERY = 0x84,
  63 };
  64 /* EC events */
  65 enum ec_event {
  66         ACPI_EC_EVENT_OBF_1 = 1,        /* Output buffer full */
  67         ACPI_EC_EVENT_IBF_0,    /* Input buffer empty */
  68 };
  69
  70 #define ACPI_EC_DELAY           500     /* Wait 500ms max. during EC ops */
  71 #define ACPI_EC_UDELAY_GLK      1000    /* Wait 1ms max. to get global lock */
  72
  73 static enum ec_mode {
  74         EC_INTR = 1,            /* Output buffer full */
  75         EC_POLL,                /* Input buffer empty */
  76 } acpi_ec_mode = EC_INTR;
  77
  78 static int acpi_ec_remove(struct acpi_device *device, int type);
  79 static int acpi_ec_start(struct acpi_device *device);
  80 static int acpi_ec_stop(struct acpi_device *device, int type);
  81 static int acpi_ec_add(struct acpi_device *device);
  82
  83 static struct acpi_driver acpi_ec_driver = {
  84         .name = "ec",
  85         .class = ACPI_EC_CLASS,
  86         .ids = ACPI_EC_HID,
  87         .ops = {
  88                 .add = acpi_ec_add,
  89                 .remove = acpi_ec_remove,
  90                 .start = acpi_ec_start,
  91                 .stop = acpi_ec_stop,
  92                 },
  93 };
  94
  95 /* If we find an EC via the ECDT, we need to keep a ptr to its context */
  96 /* External interfaces use first EC only, so remember */
  97 static struct acpi_ec {
  98         acpi_handle handle;
  99         unsigned long gpe;
 100         unsigned long command_addr;
 101         unsigned long data_addr;
 102         unsigned long global_lock;
 103         struct mutex lock;
 104         atomic_t query_pending;
 105         atomic_t event_count;
 106         wait_queue_head_t wait;
 107 } *boot_ec, *first_ec;
 108
 109 /* --------------------------------------------------------------------------
 110                              Transaction Management
 111    -------------------------------------------------------------------------- */
 112
 113 static inline u8 acpi_ec_read_status(struct acpi_ec *ec)
 114 {
 115         return inb(ec->command_addr);
 116 }
 117
 118 static inline u8 acpi_ec_read_data(struct acpi_ec *ec)
 119 {
 120         return inb(ec->data_addr);
 121 }
 122
 123 static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command)
 124 {
 125         outb(command, ec->command_addr);
 126 }
 127
 128 static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data)
 129 {
 130         outb(data, ec->data_addr);
 131 }
 132
 133 static inline int acpi_ec_check_status(struct acpi_ec *ec, enum ec_event event,
 134                                        unsigned old_count)
 135 {
 136         u8 status = acpi_ec_read_status(ec);
 137         if (old_count == atomic_read(&ec->event_count))
 138                 return 0;
 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, unsigned count)
 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, 0))
 156                                 return 0;
 157                 }
 158         } else {
 159                 if (wait_event_timeout(ec->wait,
 160                                        acpi_ec_check_status(ec, event, count),
 161                                        msecs_to_jiffies(ACPI_EC_DELAY)) ||
 162                     acpi_ec_check_status(ec, event, 0)) {
 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 static int acpi_ec_transaction_unlocked(struct acpi_ec *ec, u8 command,
 175                                         const u8 * wdata, unsigned wdata_len,
 176                                         u8 * rdata, unsigned rdata_len)
 177 {
 178         int result = 0;
 179         unsigned count = atomic_read(&ec->event_count);
 180         acpi_ec_write_cmd(ec, command);
 181
 182         for (; wdata_len > 0; --wdata_len) {
 183                 result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0, count);
 184                 if (result) {
 185                         printk(KERN_ERR PREFIX
 186                                "write_cmd timeout, command = %d\n", command);
 187                         goto end;
 188                 }
 189                 count = atomic_read(&ec->event_count);
 190                 acpi_ec_write_data(ec, *(wdata++));
 191         }
 192
 193         if (!rdata_len) {
 194                 result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0, count);
 195                 if (result) {
 196                         printk(KERN_ERR PREFIX
 197                                "finish-write timeout, command = %d\n", command);
 198                         goto end;
 199                 }
 200         } else if (command == ACPI_EC_COMMAND_QUERY) {
 201                 atomic_set(&ec->query_pending, 0);
 202         }
 203
 204         for (; rdata_len > 0; --rdata_len) {
 205                 result = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF_1, count);
 206                 if (result) {
 207                         printk(KERN_ERR PREFIX "read timeout, command = %d\n",
 208                                command);
 209                         goto end;
 210                 }
 211                 count = atomic_read(&ec->event_count);
 212                 *(rdata++) = acpi_ec_read_data(ec);
 213         }
 214       end:
 215         return result;
 216 }
 217
 218 static int acpi_ec_transaction(struct acpi_ec *ec, u8 command,
 219                                const u8 * wdata, unsigned wdata_len,
 220                                u8 * rdata, unsigned rdata_len)
 221 {
 222         int status;
 223         u32 glk;
 224
 225         if (!ec || (wdata_len && !wdata) || (rdata_len && !rdata))
 226                 return -EINVAL;
 227
 228         if (rdata)
 229                 memset(rdata, 0, rdata_len);
 230
 231         mutex_lock(&ec->lock);
 232         if (ec->global_lock) {
 233                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 234                 if (ACPI_FAILURE(status)) {
 235                         mutex_unlock(&ec->lock);
 236                         return -ENODEV;
 237                 }
 238         }
 239
 240         /* Make sure GPE is enabled before doing transaction */
 241         acpi_enable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
 242
 243         status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0, 0);
 244         if (status) {
 245                 printk(KERN_DEBUG PREFIX
 246                        "input buffer is not empty, aborting transaction\n");
 247                 goto end;
 248         }
 249
 250         status = acpi_ec_transaction_unlocked(ec, command,
 251                                               wdata, wdata_len,
 252                                               rdata, rdata_len);
 253
 254       end:
 255
 256         if (ec->global_lock)
 257                 acpi_release_global_lock(glk);
 258         mutex_unlock(&ec->lock);
 259
 260         return status;
 261 }
 262
 263 /*
 264  * Note: samsung nv5000 doesn't work with ec burst mode.
 265  * http://bugzilla.kernel.org/show_bug.cgi?id=4980
 266  */
 267 int acpi_ec_burst_enable(struct acpi_ec *ec)
 268 {
 269         u8 d;
 270         return acpi_ec_transaction(ec, ACPI_EC_BURST_ENABLE, NULL, 0, &d, 1);
 271 }
 272
 273 int acpi_ec_burst_disable(struct acpi_ec *ec)
 274 {
 275         return acpi_ec_transaction(ec, ACPI_EC_BURST_DISABLE, NULL, 0, NULL, 0);
 276 }
 277
 278 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 * data)
 279 {
 280         int result;
 281         u8 d;
 282
 283         result = acpi_ec_transaction(ec, ACPI_EC_COMMAND_READ,
 284                                      &address, 1, &d, 1);
 285         *data = d;
 286         return result;
 287 }
 288
 289 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
 290 {
 291         u8 wdata[2] = { address, data };
 292         return acpi_ec_transaction(ec, ACPI_EC_COMMAND_WRITE,
 293                                    wdata, 2, NULL, 0);
 294 }
 295
 296 /*
 297  * Externally callable EC access functions. For now, assume 1 EC only
 298  */
 299 int ec_burst_enable(void)
 300 {
 301         if (!first_ec)
 302                 return -ENODEV;
 303         return acpi_ec_burst_enable(first_ec);
 304 }
 305
 306 EXPORT_SYMBOL(ec_burst_enable);
 307
 308 int ec_burst_disable(void)
 309 {
 310         if (!first_ec)
 311                 return -ENODEV;
 312         return acpi_ec_burst_disable(first_ec);
 313 }
 314
 315 EXPORT_SYMBOL(ec_burst_disable);
 316
 317 int ec_read(u8 addr, u8 * val)
 318 {
 319         int err;
 320         u8 temp_data;
 321
 322         if (!first_ec)
 323                 return -ENODEV;
 324
 325         err = acpi_ec_read(first_ec, addr, &temp_data);
 326
 327         if (!err) {
 328                 *val = temp_data;
 329                 return 0;
 330         } else
 331                 return err;
 332 }
 333
 334 EXPORT_SYMBOL(ec_read);
 335
 336 int ec_write(u8 addr, u8 val)
 337 {
 338         int err;
 339
 340         if (!first_ec)
 341                 return -ENODEV;
 342
 343         err = acpi_ec_write(first_ec, addr, val);
 344
 345         return err;
 346 }
 347
 348 EXPORT_SYMBOL(ec_write);
 349
 350 int ec_transaction(u8 command,
 351                    const u8 * wdata, unsigned wdata_len,
 352                    u8 * rdata, unsigned rdata_len)
 353 {
 354         if (!first_ec)
 355                 return -ENODEV;
 356
 357         return acpi_ec_transaction(first_ec, command, wdata,
 358                                    wdata_len, rdata, rdata_len);
 359 }
 360
 361 EXPORT_SYMBOL(ec_transaction);
 362
 363 static int acpi_ec_query(struct acpi_ec *ec, u8 * data)
 364 {
 365         int result;
 366         u8 d;
 367
 368         if (!ec || !data)
 369                 return -EINVAL;
 370
 371         /*
 372          * Query the EC to find out which _Qxx method we need to evaluate.
 373          * Note that successful completion of the query causes the ACPI_EC_SCI
 374          * bit to be cleared (and thus clearing the interrupt source).
 375          */
 376
 377         result = acpi_ec_transaction(ec, ACPI_EC_COMMAND_QUERY, NULL, 0, &d, 1);
 378         if (result)
 379                 return result;
 380
 381         if (!d)
 382                 return -ENODATA;
 383
 384         *data = d;
 385         return 0;
 386 }
 387
 388 /* --------------------------------------------------------------------------
 389                                 Event Management
 390    -------------------------------------------------------------------------- */
 391
 392 static void acpi_ec_gpe_query(void *ec_cxt)
 393 {
 394         struct acpi_ec *ec = ec_cxt;
 395         u8 value = 0;
 396         char object_name[8];
 397
 398         if (!ec || acpi_ec_query(ec, &value))
 399                 return;
 400
 401         snprintf(object_name, 8, "_Q%2.2X", value);
 402
 403         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Evaluating %s", object_name));
 404
 405         acpi_evaluate_object(ec->handle, object_name, NULL, NULL);
 406 }
 407
 408 static u32 acpi_ec_gpe_handler(void *data)
 409 {
 410         acpi_status status = AE_OK;
 411         u8 value;
 412         struct acpi_ec *ec = data;
 413         atomic_inc(&ec->event_count);
 414
 415         if (acpi_ec_mode == EC_INTR) {
 416                 wake_up(&ec->wait);
 417         }
 418
 419         value = acpi_ec_read_status(ec);
 420         if ((value & ACPI_EC_FLAG_SCI) && !atomic_read(&ec->query_pending)) {
 421                 atomic_set(&ec->query_pending, 1);
 422                 status =
 423                     acpi_os_execute(OSL_EC_BURST_HANDLER, acpi_ec_gpe_query,
 424                                     ec);
 425         }
 426
 427         return status == AE_OK ?
 428             ACPI_INTERRUPT_HANDLED : ACPI_INTERRUPT_NOT_HANDLED;
 429 }
 430
 431 /* --------------------------------------------------------------------------
 432                              Address Space Management
 433    -------------------------------------------------------------------------- */
 434
 435 static acpi_status
 436 acpi_ec_space_setup(acpi_handle region_handle,
 437                     u32 function, void *handler_context, void **return_context)
 438 {
 439         /*
 440          * The EC object is in the handler context and is needed
 441          * when calling the acpi_ec_space_handler.
 442          */
 443         *return_context = (function != ACPI_REGION_DEACTIVATE) ?
 444             handler_context : NULL;
 445
 446         return AE_OK;
 447 }
 448
 449 static acpi_status
 450 acpi_ec_space_handler(u32 function,
 451                       acpi_physical_address address,
 452                       u32 bit_width,
 453                       acpi_integer * value,
 454                       void *handler_context, void *region_context)
 455 {
 456         int result = 0;
 457         struct acpi_ec *ec = handler_context;
 458         u64 temp = *value;
 459         acpi_integer f_v = 0;
 460         int i = 0;
 461
 462         if ((address > 0xFF) || !value || !handler_context)
 463                 return AE_BAD_PARAMETER;
 464
 465         if (bit_width != 8 && acpi_strict) {
 466                 return AE_BAD_PARAMETER;
 467         }
 468
 469       next_byte:
 470         switch (function) {
 471         case ACPI_READ:
 472                 temp = 0;
 473                 result = acpi_ec_read(ec, (u8) address, (u8 *) & temp);
 474                 break;
 475         case ACPI_WRITE:
 476                 result = acpi_ec_write(ec, (u8) address, (u8) temp);
 477                 break;
 478         default:
 479                 result = -EINVAL;
 480                 goto out;
 481                 break;
 482         }
 483
 484         bit_width -= 8;
 485         if (bit_width) {
 486                 if (function == ACPI_READ)
 487                         f_v |= temp << 8 * i;
 488                 if (function == ACPI_WRITE)
 489                         temp >>= 8;
 490                 i++;
 491                 address++;
 492                 goto next_byte;
 493         }
 494
 495         if (function == ACPI_READ) {
 496                 f_v |= temp << 8 * i;
 497                 *value = f_v;
 498         }
 499
 500       out:
 501         switch (result) {
 502         case -EINVAL:
 503                 return AE_BAD_PARAMETER;
 504                 break;
 505         case -ENODEV:
 506                 return AE_NOT_FOUND;
 507                 break;
 508         case -ETIME:
 509                 return AE_TIME;
 510                 break;
 511         default:
 512                 return AE_OK;
 513         }
 514 }
 515
 516 /* --------------------------------------------------------------------------
 517                               FS Interface (/proc)
 518    -------------------------------------------------------------------------- */
 519
 520 static struct proc_dir_entry *acpi_ec_dir;
 521
 522 static int acpi_ec_read_info(struct seq_file *seq, void *offset)
 523 {
 524         struct acpi_ec *ec = seq->private;
 525
 526         if (!ec)
 527                 goto end;
 528
 529         seq_printf(seq, "gpe:\t\t\t0x%02x\n", (u32) ec->gpe);
 530         seq_printf(seq, "ports:\t\t\t0x%02x, 0x%02x\n",
 531                    (unsigned)ec->command_addr, (unsigned)ec->data_addr);
 532         seq_printf(seq, "use global lock:\t%s\n",
 533                    ec->global_lock ? "yes" : "no");
 534       end:
 535         return 0;
 536 }
 537
 538 static int acpi_ec_info_open_fs(struct inode *inode, struct file *file)
 539 {
 540         return single_open(file, acpi_ec_read_info, PDE(inode)->data);
 541 }
 542
 543 static struct file_operations acpi_ec_info_ops = {
 544         .open = acpi_ec_info_open_fs,
 545         .read = seq_read,
 546         .llseek = seq_lseek,
 547         .release = single_release,
 548         .owner = THIS_MODULE,
 549 };
 550
 551 static int acpi_ec_add_fs(struct acpi_device *device)
 552 {
 553         struct proc_dir_entry *entry = NULL;
 554
 555         if (!acpi_device_dir(device)) {
 556                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
 557                                                      acpi_ec_dir);
 558                 if (!acpi_device_dir(device))
 559                         return -ENODEV;
 560         }
 561
 562         entry = create_proc_entry(ACPI_EC_FILE_INFO, S_IRUGO,
 563                                   acpi_device_dir(device));
 564         if (!entry)
 565                 return -ENODEV;
 566         else {
 567                 entry->proc_fops = &acpi_ec_info_ops;
 568                 entry->data = acpi_driver_data(device);
 569                 entry->owner = THIS_MODULE;
 570         }
 571
 572         return 0;
 573 }
 574
 575 static int acpi_ec_remove_fs(struct acpi_device *device)
 576 {
 577
 578         if (acpi_device_dir(device)) {
 579                 remove_proc_entry(ACPI_EC_FILE_INFO, acpi_device_dir(device));
 580                 remove_proc_entry(acpi_device_bid(device), acpi_ec_dir);
 581                 acpi_device_dir(device) = NULL;
 582         }
 583
 584         return 0;
 585 }
 586
 587 /* --------------------------------------------------------------------------
 588                                Driver Interface
 589    -------------------------------------------------------------------------- */
 590 static acpi_status
 591 ec_parse_io_ports(struct acpi_resource *resource, void *context);
 592
 593 static acpi_status
 594 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval);
 595
 596 static struct acpi_ec *make_acpi_ec(void)
 597 {
 598         struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
 599         if (!ec)
 600                 return NULL;
 601
 602         atomic_set(&ec->query_pending, 1);
 603         atomic_set(&ec->event_count, 1);
 604         mutex_init(&ec->lock);
 605         init_waitqueue_head(&ec->wait);
 606
 607         return ec;
 608 }
 609
 610 static int acpi_ec_add(struct acpi_device *device)
 611 {
 612         acpi_status status = AE_OK;
 613         struct acpi_ec *ec = NULL;
 614
 615         if (!device)
 616                 return -EINVAL;
 617
 618         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
 619         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
 620
 621         ec = make_acpi_ec();
 622         if (!ec)
 623                 return -ENOMEM;
 624
 625         status = ec_parse_device(device->handle, 0, ec, NULL);
 626         if (status != AE_CTRL_TERMINATE) {
 627                 kfree(ec);
 628                 return -EINVAL;
 629         }
 630
 631         /* Check if we found the boot EC */
 632         if (boot_ec) {
 633                 if (boot_ec->gpe == ec->gpe) {
 634                         /* We might have incorrect info for GL at boot time */
 635                         mutex_lock(&boot_ec->lock);
 636                         boot_ec->global_lock = ec->global_lock;
 637                         mutex_unlock(&boot_ec->lock);
 638                         kfree(ec);
 639                         ec = boot_ec;
 640                 }
 641         } else
 642                 first_ec = ec;
 643         ec->handle = device->handle;
 644         acpi_driver_data(device) = ec;
 645
 646         acpi_ec_add_fs(device);
 647
 648         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "%s [%s] (gpe %d) interrupt mode.",
 649                           acpi_device_name(device), acpi_device_bid(device),
 650                           (u32) ec->gpe));
 651
 652         return 0;
 653 }
 654
 655 static int acpi_ec_remove(struct acpi_device *device, int type)
 656 {
 657         struct acpi_ec *ec;
 658
 659         if (!device)
 660                 return -EINVAL;
 661
 662         ec = acpi_driver_data(device);
 663         acpi_ec_remove_fs(device);
 664         acpi_driver_data(device) = NULL;
 665         if (ec == first_ec)
 666                 first_ec = NULL;
 667
 668         /* Don't touch boot EC */
 669         if (boot_ec != ec)
 670                 kfree(ec);
 671         return 0;
 672 }
 673
 674 static acpi_status
 675 ec_parse_io_ports(struct acpi_resource *resource, void *context)
 676 {
 677         struct acpi_ec *ec = context;
 678
 679         if (resource->type != ACPI_RESOURCE_TYPE_IO)
 680                 return AE_OK;
 681
 682         /*
 683          * The first address region returned is the data port, and
 684          * the second address region returned is the status/command
 685          * port.
 686          */
 687         if (ec->data_addr == 0)
 688                 ec->data_addr = resource->data.io.minimum;
 689         else if (ec->command_addr == 0)
 690                 ec->command_addr = resource->data.io.minimum;
 691         else
 692                 return AE_CTRL_TERMINATE;
 693
 694         return AE_OK;
 695 }
 696
 697 static int ec_install_handlers(struct acpi_ec *ec)
 698 {
 699         acpi_status status;
 700         status = acpi_install_gpe_handler(NULL, ec->gpe,
 701                                           ACPI_GPE_EDGE_TRIGGERED,
 702                                           &acpi_ec_gpe_handler, ec);
 703         if (ACPI_FAILURE(status))
 704                 return -ENODEV;
 705
 706         acpi_set_gpe_type(NULL, ec->gpe, ACPI_GPE_TYPE_RUNTIME);
 707         acpi_enable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
 708
 709         status = acpi_install_address_space_handler(ec->handle,
 710                                                     ACPI_ADR_SPACE_EC,
 711                                                     &acpi_ec_space_handler,
 712                                                     &acpi_ec_space_setup, ec);
 713         if (ACPI_FAILURE(status)) {
 714                 acpi_remove_gpe_handler(NULL, ec->gpe, &acpi_ec_gpe_handler);
 715                 return -ENODEV;
 716         }
 717
 718         /* EC is fully operational, allow queries */
 719         atomic_set(&ec->query_pending, 0);
 720
 721         return 0;
 722 }
 723
 724 static int acpi_ec_start(struct acpi_device *device)
 725 {
 726         struct acpi_ec *ec;
 727
 728         if (!device)
 729                 return -EINVAL;
 730
 731         ec = acpi_driver_data(device);
 732
 733         if (!ec)
 734                 return -EINVAL;
 735
 736         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "gpe=0x%02lx, ports=0x%2lx,0x%2lx",
 737                           ec->gpe, ec->command_addr, ec->data_addr));
 738
 739         /* Boot EC is already working */
 740         if (ec == boot_ec)
 741                 return 0;
 742
 743         return ec_install_handlers(ec);
 744 }
 745
 746 static int acpi_ec_stop(struct acpi_device *device, int type)
 747 {
 748         acpi_status status;
 749         struct acpi_ec *ec;
 750
 751         if (!device)
 752                 return -EINVAL;
 753
 754         ec = acpi_driver_data(device);
 755         if (!ec)
 756                 return -EINVAL;
 757
 758         /* Don't touch boot EC */
 759         if (ec == boot_ec)
 760                 return 0;
 761
 762         status = acpi_remove_address_space_handler(ec->handle,
 763                                                    ACPI_ADR_SPACE_EC,
 764                                                    &acpi_ec_space_handler);
 765         if (ACPI_FAILURE(status))
 766                 return -ENODEV;
 767
 768         status = acpi_remove_gpe_handler(NULL, ec->gpe, &acpi_ec_gpe_handler);
 769         if (ACPI_FAILURE(status))
 770                 return -ENODEV;
 771
 772         return 0;
 773 }
 774
 775 static acpi_status
 776 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
 777 {
 778         acpi_status status;
 779
 780         struct acpi_ec *ec = context;
 781         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
 782                                      ec_parse_io_ports, ec);
 783         if (ACPI_FAILURE(status))
 784                 return status;
 785
 786         /* Get GPE bit assignment (EC events). */
 787         /* TODO: Add support for _GPE returning a package */
 788         status = acpi_evaluate_integer(handle, "_GPE", NULL, &ec->gpe);
 789         if (ACPI_FAILURE(status))
 790                 return status;
 791
 792         /* Use the global lock for all EC transactions? */
 793         acpi_evaluate_integer(handle, "_GLK", NULL, &ec->global_lock);
 794
 795         ec->handle = handle;
 796
 797         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "GPE=0x%02lx, ports=0x%2lx, 0x%2lx",
 798                           ec->gpe, ec->command_addr, ec->data_addr));
 799
 800         return AE_CTRL_TERMINATE;
 801 }
 802
 803 int __init acpi_ec_ecdt_probe(void)
 804 {
 805         int ret;
 806         acpi_status status;
 807         struct acpi_table_ecdt *ecdt_ptr;
 808
 809         boot_ec = make_acpi_ec();
 810         if (!boot_ec)
 811                 return -ENOMEM;
 812         /*
 813          * Generate a boot ec context
 814          */
 815
 816         status = acpi_get_table(ACPI_SIG_ECDT, 1,
 817                                 (struct acpi_table_header **)&ecdt_ptr);
 818         if (ACPI_FAILURE(status))
 819                 goto error;
 820
 821         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found ECDT"));
 822
 823         boot_ec->command_addr = ecdt_ptr->control.address;
 824         boot_ec->data_addr = ecdt_ptr->data.address;
 825         boot_ec->gpe = ecdt_ptr->gpe;
 826         boot_ec->handle = ACPI_ROOT_OBJECT;
 827
 828         ret = ec_install_handlers(boot_ec);
 829         if (!ret) {
 830                 first_ec = boot_ec;
 831                 return 0;
 832         }
 833       error:
 834         kfree(boot_ec);
 835         boot_ec = NULL;
 836
 837         return -ENODEV;
 838 }
 839
 840 static int __init acpi_ec_init(void)
 841 {
 842         int result = 0;
 843
 844         if (acpi_disabled)
 845                 return 0;
 846
 847         acpi_ec_dir = proc_mkdir(ACPI_EC_CLASS, acpi_root_dir);
 848         if (!acpi_ec_dir)
 849                 return -ENODEV;
 850
 851         /* Now register the driver for the EC */
 852         result = acpi_bus_register_driver(&acpi_ec_driver);
 853         if (result < 0) {
 854                 remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
 855                 return -ENODEV;
 856         }
 857
 858         return result;
 859 }
 860
 861 subsys_initcall(acpi_ec_init);
 862
 863 /* EC driver currently not unloadable */
 864 #if 0
 865 static void __exit acpi_ec_exit(void)
 866 {
 867
 868         acpi_bus_unregister_driver(&acpi_ec_driver);
 869
 870         remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
 871
 872         return;
 873 }
 874 #endif                          /* 0 */
 875
 876 static int __init acpi_ec_set_intr_mode(char *str)
 877 {
 878         int intr;
 879
 880         if (!get_option(&str, &intr))
 881                 return 0;
 882
 883         acpi_ec_mode = (intr) ? EC_INTR : EC_POLL;
 884
 885         printk(KERN_NOTICE PREFIX "%s mode.\n", intr ? "interrupt" : "polling");
 886
 887         return 1;
 888 }
 889
 890 __setup("ec_intr=", acpi_ec_set_intr_mode);