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("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 static struct acpi_ec {
  95         acpi_handle handle;
  96         unsigned long uid;
  97         unsigned long gpe;
  98         unsigned long command_addr;
  99         unsigned long data_addr;
 100         unsigned long global_lock;
 101         struct mutex lock;
 102         atomic_t query_pending;
 103         atomic_t event_count;
 104         wait_queue_head_t wait;
 105 } *ec_ecdt;
 106
 107 /* External interfaces use first EC only, so remember */
 108 static struct acpi_device *first_ec;
 109
 110 /* --------------------------------------------------------------------------
 111                              Transaction Management
 112    -------------------------------------------------------------------------- */
 113
 114 static inline u8 acpi_ec_read_status(struct acpi_ec *ec)
 115 {
 116         return inb(ec->command_addr);
 117 }
 118
 119 static inline u8 acpi_ec_read_data(struct acpi_ec *ec)
 120 {
 121         return inb(ec->data_addr);
 122 }
 123
 124 static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command)
 125 {
 126         outb(command, ec->command_addr);
 127 }
 128
 129 static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data)
 130 {
 131         outb(data, ec->data_addr);
 132 }
 133
 134 static inline int acpi_ec_check_status(struct acpi_ec *ec, enum ec_event event,
 135                                        unsigned old_count)
 136 {
 137         u8 status = acpi_ec_read_status(ec);
 138         if (old_count == atomic_read(&ec->event_count))
 139                 return 0;
 140         if (event == ACPI_EC_EVENT_OBF_1) {
 141                 if (status & ACPI_EC_FLAG_OBF)
 142                         return 1;
 143         } else if (event == ACPI_EC_EVENT_IBF_0) {
 144                 if (!(status & ACPI_EC_FLAG_IBF))
 145                         return 1;
 146         }
 147
 148         return 0;
 149 }
 150
 151 static int acpi_ec_wait(struct acpi_ec *ec, enum ec_event event, unsigned count)
 152 {
 153         if (acpi_ec_mode == EC_POLL) {
 154                 unsigned long delay = jiffies + msecs_to_jiffies(ACPI_EC_DELAY);
 155                 while (time_before(jiffies, delay)) {
 156                         if (acpi_ec_check_status(ec, event, 0))
 157                                 return 0;
 158                 }
 159         } else {
 160                 if (wait_event_timeout(ec->wait,
 161                                        acpi_ec_check_status(ec, event, count),
 162                                        msecs_to_jiffies(ACPI_EC_DELAY)) ||
 163                     acpi_ec_check_status(ec, event, 0)) {
 164                         return 0;
 165                 } else {
 166                         printk(KERN_ERR PREFIX "acpi_ec_wait timeout,"
 167                                " status = %d, expect_event = %d\n",
 168                                acpi_ec_read_status(ec), event);
 169                 }
 170         }
 171
 172         return -ETIME;
 173 }
 174
 175 static int acpi_ec_transaction_unlocked(struct acpi_ec *ec, u8 command,
 176                                         const u8 * wdata, unsigned wdata_len,
 177                                         u8 * rdata, unsigned rdata_len)
 178 {
 179         int result = 0;
 180         unsigned count = atomic_read(&ec->event_count);
 181         acpi_ec_write_cmd(ec, command);
 182
 183         for (; wdata_len > 0; --wdata_len) {
 184                 result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0, count);
 185                 if (result) {
 186                         printk(KERN_ERR PREFIX
 187                                "write_cmd timeout, command = %d\n", command);
 188                         goto end;
 189                 }
 190                 count = atomic_read(&ec->event_count);
 191                 acpi_ec_write_data(ec, *(wdata++));
 192         }
 193
 194         if (!rdata_len) {
 195                 result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0, count);
 196                 if (result) {
 197                         printk(KERN_ERR PREFIX
 198                                "finish-write timeout, command = %d\n", command);
 199                         goto end;
 200                 }
 201         } else if (command == ACPI_EC_COMMAND_QUERY) {
 202                 atomic_set(&ec->query_pending, 0);
 203         }
 204
 205         for (; rdata_len > 0; --rdata_len) {
 206                 result = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF_1, count);
 207                 if (result) {
 208                         printk(KERN_ERR PREFIX "read timeout, command = %d\n",
 209                                command);
 210                         goto end;
 211                 }
 212                 count = atomic_read(&ec->event_count);
 213                 *(rdata++) = acpi_ec_read_data(ec);
 214         }
 215       end:
 216         return result;
 217 }
 218
 219 static int acpi_ec_transaction(struct acpi_ec *ec, u8 command,
 220                                const u8 * wdata, unsigned wdata_len,
 221                                u8 * rdata, unsigned rdata_len)
 222 {
 223         int status;
 224         u32 glk;
 225
 226         if (!ec || (wdata_len && !wdata) || (rdata_len && !rdata))
 227                 return -EINVAL;
 228
 229         if (rdata)
 230                 memset(rdata, 0, rdata_len);
 231
 232         mutex_lock(&ec->lock);
 233         if (ec->global_lock) {
 234                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 235                 if (ACPI_FAILURE(status)) {
 236                         mutex_unlock(&ec->lock);
 237                         return -ENODEV;
 238                 }
 239         }
 240
 241         /* Make sure GPE is enabled before doing transaction */
 242         acpi_enable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
 243
 244         status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0, 0);
 245         if (status) {
 246                 printk(KERN_DEBUG PREFIX
 247                        "input buffer is not empty, aborting transaction\n");
 248                 goto end;
 249         }
 250
 251         status = acpi_ec_transaction_unlocked(ec, command,
 252                                               wdata, wdata_len,
 253                                               rdata, rdata_len);
 254
 255       end:
 256
 257         if (ec->global_lock)
 258                 acpi_release_global_lock(glk);
 259         mutex_unlock(&ec->lock);
 260
 261         return status;
 262 }
 263
 264 /*
 265  * Note: samsung nv5000 doesn't work with ec burst mode.
 266  * http://bugzilla.kernel.org/show_bug.cgi?id=4980
 267  */
 268 int acpi_ec_burst_enable(struct acpi_ec *ec)
 269 {
 270         u8 d;
 271         return acpi_ec_transaction(ec, ACPI_EC_BURST_ENABLE, NULL, 0, &d, 1);
 272 }
 273
 274 int acpi_ec_burst_disable(struct acpi_ec *ec)
 275 {
 276         return acpi_ec_transaction(ec, ACPI_EC_BURST_DISABLE, NULL, 0, NULL, 0);
 277 }
 278
 279 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 * data)
 280 {
 281         int result;
 282         u8 d;
 283
 284         result = acpi_ec_transaction(ec, ACPI_EC_COMMAND_READ,
 285                                      &address, 1, &d, 1);
 286         *data = d;
 287         return result;
 288 }
 289
 290 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
 291 {
 292         u8 wdata[2] = { address, data };
 293         return acpi_ec_transaction(ec, ACPI_EC_COMMAND_WRITE,
 294                                    wdata, 2, NULL, 0);
 295 }
 296
 297 /*
 298  * Externally callable EC access functions. For now, assume 1 EC only
 299  */
 300 int ec_burst_enable(void)
 301 {
 302         struct acpi_ec *ec;
 303         if (!first_ec)
 304                 return -ENODEV;
 305         ec = acpi_driver_data(first_ec);
 306         return acpi_ec_burst_enable(ec);
 307 }
 308
 309 EXPORT_SYMBOL(ec_burst_enable);
 310
 311 int ec_burst_disable(void)
 312 {
 313         struct acpi_ec *ec;
 314         if (!first_ec)
 315                 return -ENODEV;
 316         ec = acpi_driver_data(first_ec);
 317         return acpi_ec_burst_disable(ec);
 318 }
 319
 320 EXPORT_SYMBOL(ec_burst_disable);
 321
 322 int ec_read(u8 addr, u8 * val)
 323 {
 324         struct acpi_ec *ec;
 325         int err;
 326         u8 temp_data;
 327
 328         if (!first_ec)
 329                 return -ENODEV;
 330
 331         ec = acpi_driver_data(first_ec);
 332
 333         err = acpi_ec_read(ec, addr, &temp_data);
 334
 335         if (!err) {
 336                 *val = temp_data;
 337                 return 0;
 338         } else
 339                 return err;
 340 }
 341
 342 EXPORT_SYMBOL(ec_read);
 343
 344 int ec_write(u8 addr, u8 val)
 345 {
 346         struct acpi_ec *ec;
 347         int err;
 348
 349         if (!first_ec)
 350                 return -ENODEV;
 351
 352         ec = acpi_driver_data(first_ec);
 353
 354         err = acpi_ec_write(ec, addr, val);
 355
 356         return err;
 357 }
 358
 359 EXPORT_SYMBOL(ec_write);
 360
 361 int ec_transaction(u8 command,
 362                    const u8 * wdata, unsigned wdata_len,
 363                    u8 * rdata, unsigned rdata_len)
 364 {
 365         struct acpi_ec *ec;
 366
 367         if (!first_ec)
 368                 return -ENODEV;
 369
 370         ec = acpi_driver_data(first_ec);
 371
 372         return acpi_ec_transaction(ec, command, wdata,
 373                                    wdata_len, rdata, rdata_len);
 374 }
 375
 376 EXPORT_SYMBOL(ec_transaction);
 377
 378 static int acpi_ec_query(struct acpi_ec *ec, u8 * data)
 379 {
 380         int result;
 381         u8 d;
 382
 383         if (!ec || !data)
 384                 return -EINVAL;
 385
 386         /*
 387          * Query the EC to find out which _Qxx method we need to evaluate.
 388          * Note that successful completion of the query causes the ACPI_EC_SCI
 389          * bit to be cleared (and thus clearing the interrupt source).
 390          */
 391
 392         result = acpi_ec_transaction(ec, ACPI_EC_COMMAND_QUERY, NULL, 0, &d, 1);
 393         if (result)
 394                 return result;
 395
 396         if (!d)
 397                 return -ENODATA;
 398
 399         *data = d;
 400         return 0;
 401 }
 402
 403 /* --------------------------------------------------------------------------
 404                                 Event Management
 405    -------------------------------------------------------------------------- */
 406
 407 static void acpi_ec_gpe_query(void *ec_cxt)
 408 {
 409         struct acpi_ec *ec = ec_cxt;
 410         u8 value = 0;
 411         char object_name[8];
 412
 413         if (!ec || acpi_ec_query(ec, &value))
 414                 return;
 415
 416         snprintf(object_name, 8, "_Q%2.2X", value);
 417
 418         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Evaluating %s", object_name));
 419
 420         acpi_evaluate_object(ec->handle, object_name, NULL, NULL);
 421 }
 422
 423 static u32 acpi_ec_gpe_handler(void *data)
 424 {
 425         acpi_status status = AE_OK;
 426         u8 value;
 427         struct acpi_ec *ec = data;
 428         atomic_inc(&ec->event_count);
 429
 430         if (acpi_ec_mode == EC_INTR) {
 431                 wake_up(&ec->wait);
 432         }
 433
 434         value = acpi_ec_read_status(ec);
 435         if ((value & ACPI_EC_FLAG_SCI) && !atomic_read(&ec->query_pending)) {
 436                 atomic_set(&ec->query_pending, 1);
 437                 status =
 438                     acpi_os_execute(OSL_EC_BURST_HANDLER, acpi_ec_gpe_query,
 439                                     ec);
 440         }
 441
 442         return status == AE_OK ?
 443             ACPI_INTERRUPT_HANDLED : ACPI_INTERRUPT_NOT_HANDLED;
 444 }
 445
 446 /* --------------------------------------------------------------------------
 447                              Address Space Management
 448    -------------------------------------------------------------------------- */
 449
 450 static acpi_status
 451 acpi_ec_space_setup(acpi_handle region_handle,
 452                     u32 function, void *handler_context, void **return_context)
 453 {
 454         /*
 455          * The EC object is in the handler context and is needed
 456          * when calling the acpi_ec_space_handler.
 457          */
 458         *return_context = (function != ACPI_REGION_DEACTIVATE) ?
 459             handler_context : NULL;
 460
 461         return AE_OK;
 462 }
 463
 464 static acpi_status
 465 acpi_ec_space_handler(u32 function,
 466                       acpi_physical_address address,
 467                       u32 bit_width,
 468                       acpi_integer * value,
 469                       void *handler_context, void *region_context)
 470 {
 471         int result = 0;
 472         struct acpi_ec *ec = handler_context;
 473         u64 temp = *value;
 474         acpi_integer f_v = 0;
 475         int i = 0;
 476
 477         if ((address > 0xFF) || !value || !handler_context)
 478                 return AE_BAD_PARAMETER;
 479
 480         if (bit_width != 8 && acpi_strict) {
 481                 return AE_BAD_PARAMETER;
 482         }
 483
 484       next_byte:
 485         switch (function) {
 486         case ACPI_READ:
 487                 temp = 0;
 488                 result = acpi_ec_read(ec, (u8) address, (u8 *) & temp);
 489                 break;
 490         case ACPI_WRITE:
 491                 result = acpi_ec_write(ec, (u8) address, (u8) temp);
 492                 break;
 493         default:
 494                 result = -EINVAL;
 495                 goto out;
 496                 break;
 497         }
 498
 499         bit_width -= 8;
 500         if (bit_width) {
 501                 if (function == ACPI_READ)
 502                         f_v |= temp << 8 * i;
 503                 if (function == ACPI_WRITE)
 504                         temp >>= 8;
 505                 i++;
 506                 address++;
 507                 goto next_byte;
 508         }
 509
 510         if (function == ACPI_READ) {
 511                 f_v |= temp << 8 * i;
 512                 *value = f_v;
 513         }
 514
 515       out:
 516         switch (result) {
 517         case -EINVAL:
 518                 return AE_BAD_PARAMETER;
 519                 break;
 520         case -ENODEV:
 521                 return AE_NOT_FOUND;
 522                 break;
 523         case -ETIME:
 524                 return AE_TIME;
 525                 break;
 526         default:
 527                 return AE_OK;
 528         }
 529 }
 530
 531 /* --------------------------------------------------------------------------
 532                               FS Interface (/proc)
 533    -------------------------------------------------------------------------- */
 534
 535 static struct proc_dir_entry *acpi_ec_dir;
 536
 537 static int acpi_ec_read_info(struct seq_file *seq, void *offset)
 538 {
 539         struct acpi_ec *ec = seq->private;
 540
 541         if (!ec)
 542                 goto end;
 543
 544         seq_printf(seq, "gpe:                 0x%02x\n", (u32) ec->gpe);
 545         seq_printf(seq, "ports:                   0x%02x, 0x%02x\n",
 546                    (u32) ec->command_addr, (u32) ec->data_addr);
 547         seq_printf(seq, "use global lock:         %s\n",
 548                    ec->global_lock ? "yes" : "no");
 549         acpi_enable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
 550
 551       end:
 552         return 0;
 553 }
 554
 555 static int acpi_ec_info_open_fs(struct inode *inode, struct file *file)
 556 {
 557         return single_open(file, acpi_ec_read_info, PDE(inode)->data);
 558 }
 559
 560 static struct file_operations acpi_ec_info_ops = {
 561         .open = acpi_ec_info_open_fs,
 562         .read = seq_read,
 563         .llseek = seq_lseek,
 564         .release = single_release,
 565         .owner = THIS_MODULE,
 566 };
 567
 568 static int acpi_ec_add_fs(struct acpi_device *device)
 569 {
 570         struct proc_dir_entry *entry = NULL;
 571
 572         if (!acpi_device_dir(device)) {
 573                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
 574                                                      acpi_ec_dir);
 575                 if (!acpi_device_dir(device))
 576                         return -ENODEV;
 577         }
 578
 579         entry = create_proc_entry(ACPI_EC_FILE_INFO, S_IRUGO,
 580                                   acpi_device_dir(device));
 581         if (!entry)
 582                 return -ENODEV;
 583         else {
 584                 entry->proc_fops = &acpi_ec_info_ops;
 585                 entry->data = acpi_driver_data(device);
 586                 entry->owner = THIS_MODULE;
 587         }
 588
 589         return 0;
 590 }
 591
 592 static int acpi_ec_remove_fs(struct acpi_device *device)
 593 {
 594
 595         if (acpi_device_dir(device)) {
 596                 remove_proc_entry(ACPI_EC_FILE_INFO, acpi_device_dir(device));
 597                 remove_proc_entry(acpi_device_bid(device), acpi_ec_dir);
 598                 acpi_device_dir(device) = NULL;
 599         }
 600
 601         return 0;
 602 }
 603
 604 /* --------------------------------------------------------------------------
 605                                Driver Interface
 606    -------------------------------------------------------------------------- */
 607
 608 static int acpi_ec_add(struct acpi_device *device)
 609 {
 610         int result = 0;
 611         acpi_status status = AE_OK;
 612         struct acpi_ec *ec = NULL;
 613
 614         if (!device)
 615                 return -EINVAL;
 616
 617         ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
 618         if (!ec)
 619                 return -ENOMEM;
 620
 621         ec->handle = device->handle;
 622         ec->uid = -1;
 623         mutex_init(&ec->lock);
 624         atomic_set(&ec->query_pending, 0);
 625         atomic_set(&ec->event_count, 1);
 626         if (acpi_ec_mode == EC_INTR) {
 627                 init_waitqueue_head(&ec->wait);
 628         }
 629         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
 630         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
 631         acpi_driver_data(device) = ec;
 632
 633         /* Use the global lock for all EC transactions? */
 634         acpi_evaluate_integer(ec->handle, "_GLK", NULL, &ec->global_lock);
 635
 636         /* XXX we don't test uids, because on some boxes ecdt uid = 0, see:
 637            http://bugzilla.kernel.org/show_bug.cgi?id=6111 */
 638         if (ec_ecdt) {
 639                 acpi_remove_address_space_handler(ACPI_ROOT_OBJECT,
 640                                                   ACPI_ADR_SPACE_EC,
 641                                                   &acpi_ec_space_handler);
 642
 643                 acpi_remove_gpe_handler(NULL, ec_ecdt->gpe,
 644                                         &acpi_ec_gpe_handler);
 645
 646                 kfree(ec_ecdt);
 647         }
 648
 649         /* Get GPE bit assignment (EC events). */
 650         /* TODO: Add support for _GPE returning a package */
 651         status = acpi_evaluate_integer(ec->handle, "_GPE", NULL, &ec->gpe);
 652         if (ACPI_FAILURE(status)) {
 653                 ACPI_EXCEPTION((AE_INFO, status,
 654                                 "Obtaining GPE bit assignment"));
 655                 result = -ENODEV;
 656                 goto end;
 657         }
 658
 659         result = acpi_ec_add_fs(device);
 660         if (result)
 661                 goto end;
 662
 663         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "%s [%s] (gpe %d) interrupt mode.",
 664                           acpi_device_name(device), acpi_device_bid(device),
 665                           (u32) ec->gpe));
 666
 667         if (!first_ec)
 668                 first_ec = device;
 669
 670       end:
 671         if (result)
 672                 kfree(ec);
 673
 674         return result;
 675 }
 676
 677 static int acpi_ec_remove(struct acpi_device *device, int type)
 678 {
 679         struct acpi_ec *ec = NULL;
 680
 681         if (!device)
 682                 return -EINVAL;
 683
 684         ec = acpi_driver_data(device);
 685
 686         acpi_ec_remove_fs(device);
 687
 688         kfree(ec);
 689
 690         return 0;
 691 }
 692
 693 static acpi_status
 694 acpi_ec_io_ports(struct acpi_resource *resource, void *context)
 695 {
 696         struct acpi_ec *ec = context;
 697
 698         if (resource->type != ACPI_RESOURCE_TYPE_IO) {
 699                 return AE_OK;
 700         }
 701
 702         /*
 703          * The first address region returned is the data port, and
 704          * the second address region returned is the status/command
 705          * port.
 706          */
 707         if (ec->data_addr == 0) {
 708                 ec->data_addr = resource->data.io.minimum;
 709         } else if (ec->command_addr == 0) {
 710                 ec->command_addr = resource->data.io.minimum;
 711         } else {
 712                 return AE_CTRL_TERMINATE;
 713         }
 714
 715         return AE_OK;
 716 }
 717
 718 static int acpi_ec_start(struct acpi_device *device)
 719 {
 720         acpi_status status = AE_OK;
 721         struct acpi_ec *ec = NULL;
 722
 723         if (!device)
 724                 return -EINVAL;
 725
 726         ec = acpi_driver_data(device);
 727
 728         if (!ec)
 729                 return -EINVAL;
 730
 731         /*
 732          * Get I/O port addresses. Convert to GAS format.
 733          */
 734         status = acpi_walk_resources(ec->handle, METHOD_NAME__CRS,
 735                                      acpi_ec_io_ports, ec);
 736         if (ACPI_FAILURE(status) || ec->command_addr == 0) {
 737                 ACPI_EXCEPTION((AE_INFO, status,
 738                                 "Error getting I/O port addresses"));
 739                 return -ENODEV;
 740         }
 741
 742         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "gpe=0x%02lx, ports=0x%2lx,0x%2lx",
 743                           ec->gpe, ec->command_addr, ec->data_addr));
 744
 745         /*
 746          * Install GPE handler
 747          */
 748         status = acpi_install_gpe_handler(NULL, ec->gpe,
 749                                           ACPI_GPE_EDGE_TRIGGERED,
 750                                           &acpi_ec_gpe_handler, ec);
 751         if (ACPI_FAILURE(status)) {
 752                 return -ENODEV;
 753         }
 754         acpi_set_gpe_type(NULL, ec->gpe, ACPI_GPE_TYPE_RUNTIME);
 755         acpi_enable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
 756
 757         status = acpi_install_address_space_handler(ec->handle,
 758                                                     ACPI_ADR_SPACE_EC,
 759                                                     &acpi_ec_space_handler,
 760                                                     &acpi_ec_space_setup, ec);
 761         if (ACPI_FAILURE(status)) {
 762                 acpi_remove_gpe_handler(NULL, ec->gpe, &acpi_ec_gpe_handler);
 763                 return -ENODEV;
 764         }
 765
 766         return AE_OK;
 767 }
 768
 769 static int acpi_ec_stop(struct acpi_device *device, int type)
 770 {
 771         acpi_status status = AE_OK;
 772         struct acpi_ec *ec = NULL;
 773
 774         if (!device)
 775                 return -EINVAL;
 776
 777         ec = acpi_driver_data(device);
 778
 779         status = acpi_remove_address_space_handler(ec->handle,
 780                                                    ACPI_ADR_SPACE_EC,
 781                                                    &acpi_ec_space_handler);
 782         if (ACPI_FAILURE(status))
 783                 return -ENODEV;
 784
 785         status = acpi_remove_gpe_handler(NULL, ec->gpe, &acpi_ec_gpe_handler);
 786         if (ACPI_FAILURE(status))
 787                 return -ENODEV;
 788
 789         return 0;
 790 }
 791
 792 static int __init acpi_ec_get_real_ecdt(void)
 793 {
 794         acpi_status status;
 795         struct acpi_table_ecdt *ecdt_ptr;
 796
 797         status = acpi_get_table(ACPI_SIG_ECDT, 1,
 798                                 (struct acpi_table_header **)&ecdt_ptr);
 799         if (ACPI_FAILURE(status))
 800                 return -ENODEV;
 801
 802         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found ECDT"));
 803
 804         /*
 805          * Generate a temporary ec context to use until the namespace is scanned
 806          */
 807         ec_ecdt = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
 808         if (!ec_ecdt)
 809                 return -ENOMEM;
 810
 811         mutex_init(&ec_ecdt->lock);
 812         atomic_set(&ec_ecdt->event_count, 1);
 813         if (acpi_ec_mode == EC_INTR) {
 814                 init_waitqueue_head(&ec_ecdt->wait);
 815         }
 816         ec_ecdt->command_addr = ecdt_ptr->control.address;
 817         ec_ecdt->data_addr = ecdt_ptr->data.address;
 818         ec_ecdt->gpe = ecdt_ptr->gpe;
 819         ec_ecdt->uid = ecdt_ptr->uid;
 820
 821         status = acpi_get_handle(NULL, ecdt_ptr->id, &ec_ecdt->handle);
 822         if (ACPI_FAILURE(status)) {
 823                 goto error;
 824         }
 825
 826         return 0;
 827       error:
 828         ACPI_EXCEPTION((AE_INFO, status, "Could not use ECDT"));
 829         kfree(ec_ecdt);
 830         ec_ecdt = NULL;
 831
 832         return -ENODEV;
 833 }
 834
 835 int __init acpi_ec_ecdt_probe(void)
 836 {
 837         acpi_status status;
 838         int ret;
 839
 840         ret = acpi_ec_get_real_ecdt();
 841         if (ret)
 842                 return 0;
 843
 844         /*
 845          * Install GPE handler
 846          */
 847         status = acpi_install_gpe_handler(NULL, ec_ecdt->gpe,
 848                                           ACPI_GPE_EDGE_TRIGGERED,
 849                                           &acpi_ec_gpe_handler, ec_ecdt);
 850         if (ACPI_FAILURE(status)) {
 851                 goto error;
 852         }
 853         acpi_set_gpe_type(NULL, ec_ecdt->gpe, ACPI_GPE_TYPE_RUNTIME);
 854         acpi_enable_gpe(NULL, ec_ecdt->gpe, ACPI_NOT_ISR);
 855
 856         status = acpi_install_address_space_handler(ACPI_ROOT_OBJECT,
 857                                                     ACPI_ADR_SPACE_EC,
 858                                                     &acpi_ec_space_handler,
 859                                                     &acpi_ec_space_setup,
 860                                                     ec_ecdt);
 861         if (ACPI_FAILURE(status)) {
 862                 acpi_remove_gpe_handler(NULL, ec_ecdt->gpe,
 863                                         &acpi_ec_gpe_handler);
 864                 goto error;
 865         }
 866
 867         return 0;
 868
 869       error:
 870         ACPI_EXCEPTION((AE_INFO, status, "Could not use ECDT"));
 871         kfree(ec_ecdt);
 872         ec_ecdt = NULL;
 873
 874         return -ENODEV;
 875 }
 876
 877 static int __init acpi_ec_init(void)
 878 {
 879         int result = 0;
 880
 881         if (acpi_disabled)
 882                 return 0;
 883
 884         acpi_ec_dir = proc_mkdir(ACPI_EC_CLASS, acpi_root_dir);
 885         if (!acpi_ec_dir)
 886                 return -ENODEV;
 887
 888         /* Now register the driver for the EC */
 889         result = acpi_bus_register_driver(&acpi_ec_driver);
 890         if (result < 0) {
 891                 remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
 892                 return -ENODEV;
 893         }
 894
 895         return result;
 896 }
 897
 898 subsys_initcall(acpi_ec_init);
 899
 900 /* EC driver currently not unloadable */
 901 #if 0
 902 static void __exit acpi_ec_exit(void)
 903 {
 904
 905         acpi_bus_unregister_driver(&acpi_ec_driver);
 906
 907         remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
 908
 909         return;
 910 }
 911 #endif                          /* 0 */
 912
 913 static int __init acpi_ec_set_intr_mode(char *str)
 914 {
 915         int intr;
 916
 917         if (!get_option(&str, &intr))
 918                 return 0;
 919
 920         if (intr) {
 921                 acpi_ec_mode = EC_INTR;
 922         } else {
 923                 acpi_ec_mode = EC_POLL;
 924         }
 925         acpi_ec_driver.ops.add = acpi_ec_add;
 926         printk(KERN_NOTICE PREFIX "%s mode.\n", intr ? "interrupt" : "polling");
 927
 928         return 1;
 929 }
 930
 931 __setup("ec_intr=", acpi_ec_set_intr_mode);