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   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 } *boot_ec;
 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 static acpi_status
 608 ec_parse_io_ports(struct acpi_resource *resource, void *context);
 609
 610 static acpi_status
 611 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval);
 612
 613 static struct acpi_ec *make_acpi_ec(void)
 614 {
 615         struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
 616         if (!ec)
 617                 return NULL;
 618
 619         atomic_set(&ec->query_pending, 0);
 620         atomic_set(&ec->event_count, 1);
 621         mutex_init(&ec->lock);
 622         init_waitqueue_head(&ec->wait);
 623
 624         return ec;
 625 }
 626
 627 static int acpi_ec_add(struct acpi_device *device)
 628 {
 629         acpi_status status = AE_OK;
 630         struct acpi_ec *ec = NULL;
 631
 632         if (!device)
 633                 return -EINVAL;
 634
 635         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
 636         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
 637
 638         ec = make_acpi_ec();
 639         if (!ec)
 640                 return -ENOMEM;
 641
 642         status = ec_parse_device(device->handle, 0, ec, NULL);
 643         if (status != AE_CTRL_TERMINATE) {
 644                 kfree(ec);
 645                 return -EINVAL;
 646         }
 647
 648         /* Check if we found the boot EC */
 649         if (boot_ec) {
 650                 if (boot_ec->gpe == ec->gpe) {
 651                         /* We might have incorrect info for GL at boot time */
 652                         mutex_lock(&boot_ec->lock);
 653                         boot_ec->global_lock = ec->global_lock;
 654                         mutex_unlock(&boot_ec->lock);
 655                         kfree(ec);
 656                         ec = boot_ec;
 657                 }
 658         }
 659         ec->handle = device->handle;
 660         acpi_driver_data(device) = ec;
 661         if (!first_ec)
 662                 first_ec = device;
 663
 664         acpi_ec_add_fs(device);
 665
 666         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "%s [%s] (gpe %d) interrupt mode.",
 667                           acpi_device_name(device), acpi_device_bid(device),
 668                           (u32) ec->gpe));
 669
 670         return 0;
 671 }
 672
 673 static int acpi_ec_remove(struct acpi_device *device, int type)
 674 {
 675         struct acpi_ec *ec = NULL;
 676
 677         if (!device)
 678                 return -EINVAL;
 679
 680         ec = acpi_driver_data(device);
 681
 682         acpi_ec_remove_fs(device);
 683
 684         acpi_driver_data(device) = NULL;
 685         if (device == first_ec)
 686                 first_ec = NULL;
 687
 688         /* Don't touch boot EC */
 689         if (boot_ec != ec)
 690                 kfree(ec);
 691
 692         return 0;
 693 }
 694
 695 static acpi_status
 696 ec_parse_io_ports(struct acpi_resource *resource, void *context)
 697 {
 698         struct acpi_ec *ec = context;
 699
 700         if (resource->type != ACPI_RESOURCE_TYPE_IO) {
 701                 return AE_OK;
 702         }
 703
 704         /*
 705          * The first address region returned is the data port, and
 706          * the second address region returned is the status/command
 707          * port.
 708          */
 709         if (ec->data_addr == 0) {
 710                 ec->data_addr = resource->data.io.minimum;
 711         } else if (ec->command_addr == 0) {
 712                 ec->command_addr = resource->data.io.minimum;
 713         } else {
 714                 return AE_CTRL_TERMINATE;
 715         }
 716
 717         return AE_OK;
 718 }
 719
 720 static int ec_install_handlers(struct acpi_ec *ec)
 721 {
 722         acpi_status status;
 723         status = acpi_install_gpe_handler(NULL, ec->gpe,
 724                                           ACPI_GPE_EDGE_TRIGGERED,
 725                                           &acpi_ec_gpe_handler, ec);
 726         if (ACPI_FAILURE(status))
 727                 return -ENODEV;
 728         acpi_set_gpe_type(NULL, ec->gpe, ACPI_GPE_TYPE_RUNTIME);
 729         acpi_enable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
 730
 731         status = acpi_install_address_space_handler(ec->handle,
 732                                                     ACPI_ADR_SPACE_EC,
 733                                                     &acpi_ec_space_handler,
 734                                                     &acpi_ec_space_setup, ec);
 735         if (ACPI_FAILURE(status)) {
 736                 acpi_remove_gpe_handler(NULL, ec->gpe, &acpi_ec_gpe_handler);
 737                 return -ENODEV;
 738         }
 739
 740         return 0;
 741 }
 742
 743 static int acpi_ec_start(struct acpi_device *device)
 744 {
 745         struct acpi_ec *ec;
 746
 747         if (!device)
 748                 return -EINVAL;
 749
 750         ec = acpi_driver_data(device);
 751
 752         if (!ec)
 753                 return -EINVAL;
 754
 755         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "gpe=0x%02lx, ports=0x%2lx,0x%2lx",
 756                           ec->gpe, ec->command_addr, ec->data_addr));
 757
 758         /* Boot EC is already working */
 759         if (ec == boot_ec)
 760                 return 0;
 761
 762         return ec_install_handlers(ec);
 763 }
 764
 765 static int acpi_ec_stop(struct acpi_device *device, int type)
 766 {
 767         acpi_status status;
 768         struct acpi_ec *ec;
 769
 770         if (!device)
 771                 return -EINVAL;
 772
 773         ec = acpi_driver_data(device);
 774         if (!ec)
 775                 return -EINVAL;
 776
 777         /* Don't touch boot EC */
 778         if (ec == boot_ec)
 779                 return 0;
 780
 781         status = acpi_remove_address_space_handler(ec->handle,
 782                                                    ACPI_ADR_SPACE_EC,
 783                                                    &acpi_ec_space_handler);
 784         if (ACPI_FAILURE(status))
 785                 return -ENODEV;
 786
 787         status = acpi_remove_gpe_handler(NULL, ec->gpe, &acpi_ec_gpe_handler);
 788         if (ACPI_FAILURE(status))
 789                 return -ENODEV;
 790
 791         return 0;
 792 }
 793
 794 static acpi_status
 795 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
 796 {
 797         acpi_status status;
 798
 799         struct acpi_ec *ec = context;
 800         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
 801                                      ec_parse_io_ports, ec);
 802         if (ACPI_FAILURE(status))
 803                 return status;
 804
 805         /* Get GPE bit assignment (EC events). */
 806         /* TODO: Add support for _GPE returning a package */
 807         status = acpi_evaluate_integer(handle, "_GPE", NULL, &ec->gpe);
 808         if (ACPI_FAILURE(status))
 809                 return status;
 810
 811         /* Use the global lock for all EC transactions? */
 812         acpi_evaluate_integer(handle, "_GLK", NULL, &ec->global_lock);
 813
 814         ec->handle = handle;
 815
 816         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "GPE=0x%02lx, ports=0x%2lx, 0x%2lx",
 817                           ec->gpe, ec->command_addr, ec->data_addr));
 818
 819         return AE_CTRL_TERMINATE;
 820 }
 821
 822 int __init acpi_ec_ecdt_probe(void)
 823 {
 824         int ret;
 825         acpi_status status;
 826         struct acpi_table_ecdt *ecdt_ptr;
 827
 828         boot_ec = make_acpi_ec();
 829         if (!boot_ec)
 830                 return -ENOMEM;
 831         /*
 832          * Generate a boot ec context
 833          */
 834
 835         status = acpi_get_table(ACPI_SIG_ECDT, 1,
 836                                 (struct acpi_table_header **)&ecdt_ptr);
 837         if (ACPI_FAILURE(status))
 838                 goto error;
 839
 840         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found ECDT"));
 841
 842         boot_ec->command_addr = ecdt_ptr->control.address;
 843         boot_ec->data_addr = ecdt_ptr->data.address;
 844         boot_ec->gpe = ecdt_ptr->gpe;
 845         boot_ec->uid = ecdt_ptr->uid;
 846         boot_ec->handle = ACPI_ROOT_OBJECT;
 847
 848         ret = ec_install_handlers(boot_ec);
 849         if (!ret)
 850                 return 0;
 851       error:
 852         kfree(boot_ec);
 853         boot_ec = NULL;
 854
 855         return -ENODEV;
 856 }
 857
 858 static int __init acpi_ec_init(void)
 859 {
 860         int result = 0;
 861
 862         if (acpi_disabled)
 863                 return 0;
 864
 865         acpi_ec_dir = proc_mkdir(ACPI_EC_CLASS, acpi_root_dir);
 866         if (!acpi_ec_dir)
 867                 return -ENODEV;
 868
 869         /* Now register the driver for the EC */
 870         result = acpi_bus_register_driver(&acpi_ec_driver);
 871         if (result < 0) {
 872                 remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
 873                 return -ENODEV;
 874         }
 875
 876         return result;
 877 }
 878
 879 subsys_initcall(acpi_ec_init);
 880
 881 /* EC driver currently not unloadable */
 882 #if 0
 883 static void __exit acpi_ec_exit(void)
 884 {
 885
 886         acpi_bus_unregister_driver(&acpi_ec_driver);
 887
 888         remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
 889
 890         return;
 891 }
 892 #endif                          /* 0 */
 893
 894 static int __init acpi_ec_set_intr_mode(char *str)
 895 {
 896         int intr;
 897
 898         if (!get_option(&str, &intr))
 899                 return 0;
 900
 901         acpi_ec_mode = (intr) ? EC_INTR : EC_POLL;
 902
 903         printk(KERN_NOTICE PREFIX "%s mode.\n", intr ? "interrupt" : "polling");
 904
 905         return 1;
 906 }
 907
 908 __setup("ec_intr=", acpi_ec_set_intr_mode);