drivers/acpi/ec.c

   1 /*
   2  *  acpi_ec.c - ACPI Embedded Controller Driver ($Revision: 38 $)
   3  *
   4  *  Copyright (C) 2004 Luming Yu <luming.yu@intel.com>
   5  *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
   6  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
   7  *
   8  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   9  *
  10  *  This program is free software; you can redistribute it and/or modify
  11  *  it under the terms of the GNU General Public License as published by
  12  *  the Free Software Foundation; either version 2 of the License, or (at
  13  *  your option) any later version.
  14  *
  15  *  This program is distributed in the hope that it will be useful, but
  16  *  WITHOUT ANY WARRANTY; without even the implied warranty of
  17  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  18  *  General Public License for more details.
  19  *
  20  *  You should have received a copy of the GNU General Public License along
  21  *  with this program; if not, write to the Free Software Foundation, Inc.,
  22  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
  23  *
  24  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  25  */
  26
  27 #include <linux/kernel.h>
  28 #include <linux/module.h>
  29 #include <linux/init.h>
  30 #include <linux/types.h>
  31 #include <linux/delay.h>
  32 #include <linux/proc_fs.h>
  33 #include <linux/seq_file.h>
  34 #include <linux/interrupt.h>
  35 #include <asm/io.h>
  36 #include <acpi/acpi_bus.h>
  37 #include <acpi/acpi_drivers.h>
  38 #include <acpi/actypes.h>
  39
  40 #define _COMPONENT              ACPI_EC_COMPONENT
  41 ACPI_MODULE_NAME("acpi_ec")
  42 #define ACPI_EC_COMPONENT               0x00100000
  43 #define ACPI_EC_CLASS                   "embedded_controller"
  44 #define ACPI_EC_HID                     "PNP0C09"
  45 #define ACPI_EC_DRIVER_NAME             "ACPI Embedded Controller Driver"
  46 #define ACPI_EC_DEVICE_NAME             "Embedded Controller"
  47 #define ACPI_EC_FILE_INFO               "info"
  48
  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
  55 /* EC commands */
  56 #define ACPI_EC_COMMAND_READ    0x80
  57 #define ACPI_EC_COMMAND_WRITE   0x81
  58 #define ACPI_EC_BURST_ENABLE    0x82
  59 #define ACPI_EC_BURST_DISABLE   0x83
  60 #define ACPI_EC_COMMAND_QUERY   0x84
  61
  62 /* EC events */
  63 enum {
  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           50      /* Wait 50ms max. during EC ops */
  69 #define ACPI_EC_UDELAY_GLK      1000    /* Wait 1ms max. to get global lock */
  70 #define ACPI_EC_UDELAY         100      /* Poll @ 100us increments */
  71 #define ACPI_EC_UDELAY_COUNT   1000     /* Wait 10ms max. during EC ops */
  72
  73 enum {
  74         EC_INTR = 1,    /* Output buffer full */
  75         EC_POLL,                /* Input buffer empty */
  76 };
  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 = ACPI_EC_DRIVER_NAME,
  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 struct acpi_ec {
  95         acpi_handle handle;
  96         unsigned long uid;
  97         unsigned long gpe_bit;
  98         struct acpi_generic_address status_addr;
  99         struct acpi_generic_address command_addr;
 100         struct acpi_generic_address data_addr;
 101         unsigned long global_lock;
 102         struct semaphore sem;
 103         unsigned int expect_event;
 104         atomic_t leaving_burst; /* 0 : No, 1 : Yes, 2: abort */
 105         wait_queue_head_t wait;
 106 };
 107
 108 /* If we find an EC via the ECDT, we need to keep a ptr to its context */
 109 static struct acpi_ec *ec_ecdt;
 110
 111 /* External interfaces use first EC only, so remember */
 112 static struct acpi_device *first_ec;
 113 static int acpi_ec_mode = EC_INTR;
 114
 115 /* --------------------------------------------------------------------------
 116                              Transaction Management
 117    -------------------------------------------------------------------------- */
 118
 119 static u32 acpi_ec_read_status(struct acpi_ec *ec)
 120 {
 121         u32 status = 0;
 122
 123         acpi_hw_low_level_read(8, &status, &ec->status_addr);
 124         return status;
 125 }
 126
 127 static u32 acpi_ec_read_data(struct acpi_ec *ec)
 128 {
 129         u32 data = 0;
 130
 131         acpi_hw_low_level_read(8, &data, &ec->data_addr);
 132         return data;
 133 }
 134
 135 static void acpi_ec_write_cmd(struct acpi_ec *ec, u32 command)
 136 {
 137         acpi_hw_low_level_write(8, command, &ec->command_addr);
 138 }
 139
 140 static void acpi_ec_write_data(struct acpi_ec *ec, u32 data)
 141 {
 142         acpi_hw_low_level_write(8, data, &ec->data_addr);
 143 }
 144
 145 static int acpi_ec_check_status(u32 status, u8 event) {
 146
 147         switch (event) {
 148         case ACPI_EC_EVENT_OBF_1:
 149                 if (status & ACPI_EC_FLAG_OBF)
 150                         return 1;
 151                 break;
 152         case ACPI_EC_EVENT_IBF_0:
 153                 if (!(status & ACPI_EC_FLAG_IBF))
 154                         return 1;
 155                 break;
 156         default:
 157                 break;
 158         }
 159
 160         return 0;
 161 }
 162
 163 static int acpi_ec_wait(struct acpi_ec *ec, u8 event)
 164 {
 165         int i = (acpi_ec_mode == EC_POLL) ? ACPI_EC_UDELAY_COUNT : 0;
 166         long time_left;
 167
 168         ec->expect_event = event;
 169         if (acpi_ec_check_status(acpi_ec_read_status(ec), event)) {
 170                 ec->expect_event = 0;
 171                 return 0;
 172         }
 173
 174         do {
 175                 if (acpi_ec_mode == EC_POLL) {
 176                         udelay(ACPI_EC_UDELAY);
 177                 } else {
 178                         time_left = wait_event_timeout(ec->wait,
 179                                     !ec->expect_event,
 180                                     msecs_to_jiffies(ACPI_EC_DELAY));
 181                         if (time_left > 0) {
 182                                 ec->expect_event = 0;
 183                                 return 0;
 184                         }
 185                 }
 186                 if (acpi_ec_check_status(acpi_ec_read_status(ec), event)) {
 187                         ec->expect_event = 0;
 188                         return 0;
 189                 }
 190         } while (--i > 0);
 191
 192         ec->expect_event = 0;
 193
 194         return -ETIME;
 195 }
 196
 197 #ifdef ACPI_FUTURE_USAGE
 198 /*
 199  * Note: samsung nv5000 doesn't work with ec burst mode.
 200  * http://bugzilla.kernel.org/show_bug.cgi?id=4980
 201  */
 202 int acpi_ec_enter_burst_mode(struct acpi_ec *ec)
 203 {
 204         u32 tmp = 0;
 205         u32 status = 0;
 206
 207
 208         status = acpi_ec_read_status(ec);
 209         if (status != -EINVAL && !(status & ACPI_EC_FLAG_BURST)) {
 210                 status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0);
 211                 if (status)
 212                         goto end;
 213                 acpi_ec_write_cmd(ec, ACPI_EC_BURST_ENABLE);
 214                 status = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF_1);
 215                 tmp = acpi_ec_read_data(ec);
 216                 if (tmp != 0x90) {      /* Burst ACK byte */
 217                         return -EINVAL;
 218                 }
 219         }
 220
 221         atomic_set(&ec->leaving_burst, 0);
 222         return 0;
 223   end:
 224         ACPI_EXCEPTION((AE_INFO, status, "EC wait, burst mode"));
 225         return -1;
 226 }
 227
 228 int acpi_ec_leave_burst_mode(struct acpi_ec *ec)
 229 {
 230         u32 status = 0;
 231
 232
 233         status = acpi_ec_read_status(ec);
 234         if (status != -EINVAL && (status & ACPI_EC_FLAG_BURST)){
 235                 status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0);
 236                 if(status)
 237                         goto end;
 238                 acpi_ec_write_cmd(ec, ACPI_EC_BURST_DISABLE);
 239                 acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0);
 240         }
 241         atomic_set(&ec->leaving_burst, 1);
 242         return 0;
 243   end:
 244         ACPI_EXCEPTION((AE_INFO, status, "EC leave burst mode"));
 245         return -1;
 246 }
 247 #endif /* ACPI_FUTURE_USAGE */
 248
 249 static int acpi_ec_transaction_unlocked(struct acpi_ec *ec, u8 command,
 250                                         const u8 *wdata, unsigned wdata_len,
 251                                         u8 *rdata, unsigned rdata_len)
 252 {
 253         int result;
 254
 255         acpi_ec_write_cmd(ec, command);
 256
 257         for (; wdata_len > 0; wdata_len --) {
 258                 result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0);
 259                 if (result)
 260                         return result;
 261                 acpi_ec_write_data(ec, *(wdata++));
 262         }
 263
 264         if (command == ACPI_EC_COMMAND_WRITE) {
 265                 result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0);
 266                 if (result)
 267                         return result;
 268         }
 269
 270         for (; rdata_len > 0; rdata_len --) {
 271                 u32 d;
 272
 273                 result = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF_1);
 274                 if (result)
 275                         return result;
 276
 277                 d = acpi_ec_read_data(ec);
 278                 *(rdata++) = (u8) d;
 279         }
 280
 281         return 0;
 282 }
 283
 284 static int acpi_ec_transaction(struct acpi_ec *ec, u8 command,
 285                                 const u8 *wdata, unsigned wdata_len,
 286                                 u8 *rdata, unsigned rdata_len)
 287 {
 288         int status;
 289         u32 glk;
 290
 291         if (!ec || (wdata_len && !wdata) || (rdata_len && !rdata))
 292                 return -EINVAL;
 293
 294         if (rdata)
 295                 memset(rdata, 0, rdata_len);
 296
 297         if (ec->global_lock) {
 298                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 299                 if (ACPI_FAILURE(status))
 300                         return -ENODEV;
 301         }
 302         down(&ec->sem);
 303
 304         status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0);
 305         if (status) {
 306                 printk(KERN_DEBUG PREFIX "read EC, IB not empty\n");
 307                 goto end;
 308         }
 309
 310         status = acpi_ec_transaction_unlocked(ec, command,
 311                                               wdata, wdata_len,
 312                                               rdata, rdata_len);
 313
 314 end:
 315         up(&ec->sem);
 316
 317         if (ec->global_lock)
 318                 acpi_release_global_lock(glk);
 319
 320         return status;
 321 }
 322
 323 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u32 * data)
 324 {
 325         int result;
 326         u8 d;
 327
 328         result = acpi_ec_transaction(ec, ACPI_EC_COMMAND_READ,
 329                                      &address, 1, &d, 1);
 330         *data = d;
 331         return result;
 332 }
 333 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
 334 {
 335         u8 wdata[2] = { address, data };
 336         return acpi_ec_transaction(ec, ACPI_EC_COMMAND_WRITE,
 337                                    wdata, 2, NULL, 0);
 338 }
 339
 340 /*
 341  * Externally callable EC access functions. For now, assume 1 EC only
 342  */
 343 int ec_read(u8 addr, u8 * val)
 344 {
 345         struct acpi_ec *ec;
 346         int err;
 347         u32 temp_data;
 348
 349         if (!first_ec)
 350                 return -ENODEV;
 351
 352         ec = acpi_driver_data(first_ec);
 353
 354         err = acpi_ec_read(ec, addr, &temp_data);
 355
 356         if (!err) {
 357                 *val = temp_data;
 358                 return 0;
 359         } else
 360                 return err;
 361 }
 362
 363 EXPORT_SYMBOL(ec_read);
 364
 365 int ec_write(u8 addr, u8 val)
 366 {
 367         struct acpi_ec *ec;
 368         int err;
 369
 370         if (!first_ec)
 371                 return -ENODEV;
 372
 373         ec = acpi_driver_data(first_ec);
 374
 375         err = acpi_ec_write(ec, addr, val);
 376
 377         return err;
 378 }
 379
 380 EXPORT_SYMBOL(ec_write);
 381
 382 extern int ec_transaction(u8 command,
 383                           const u8 *wdata, unsigned wdata_len,
 384                           u8 *rdata, unsigned rdata_len)
 385 {
 386         struct acpi_ec *ec;
 387
 388         if (!first_ec)
 389                 return -ENODEV;
 390
 391         ec = acpi_driver_data(first_ec);
 392
 393         return acpi_ec_transaction(ec, command, wdata,
 394                                    wdata_len, rdata, rdata_len);
 395 }
 396
 397 static int acpi_ec_query(struct acpi_ec *ec, u32 * data)
 398 {
 399         int result;
 400         u8 d;
 401
 402         if (!ec || !data)
 403                 return -EINVAL;
 404
 405         /*
 406          * Query the EC to find out which _Qxx method we need to evaluate.
 407          * Note that successful completion of the query causes the ACPI_EC_SCI
 408          * bit to be cleared (and thus clearing the interrupt source).
 409          */
 410
 411         result = acpi_ec_transaction(ec, ACPI_EC_COMMAND_QUERY, NULL, 0, &d, 1);
 412         if (result)
 413                 return result;
 414
 415         if (!d)
 416                 return -ENODATA;
 417
 418         *data = d;
 419         return 0;
 420 }
 421
 422 /* --------------------------------------------------------------------------
 423                                 Event Management
 424    -------------------------------------------------------------------------- */
 425
 426 struct acpi_ec_query_data {
 427         acpi_handle handle;
 428         u8 data;
 429 };
 430
 431 static void acpi_ec_gpe_query(void *ec_cxt)
 432 {
 433         struct acpi_ec *ec = (struct acpi_ec *)ec_cxt;
 434         u32 value = 0;
 435         static char object_name[5] = { '_', 'Q', '0', '0', '\0' };
 436         const char hex[] = { '0', '1', '2', '3', '4', '5', '6', '7',
 437                 '8', '9', 'A', 'B', 'C', 'D', 'E', 'F'
 438         };
 439
 440
 441         if (!ec_cxt)
 442                 goto end;
 443
 444         value = acpi_ec_read_status(ec);
 445
 446         if (!(value & ACPI_EC_FLAG_SCI))
 447                 goto end;
 448
 449         if (acpi_ec_query(ec, &value))
 450                 goto end;
 451
 452         object_name[2] = hex[((value >> 4) & 0x0F)];
 453         object_name[3] = hex[(value & 0x0F)];
 454
 455         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Evaluating %s", object_name));
 456
 457         acpi_evaluate_object(ec->handle, object_name, NULL, NULL);
 458
 459       end:
 460         acpi_enable_gpe(NULL, ec->gpe_bit, ACPI_NOT_ISR);
 461 }
 462
 463 static u32 acpi_ec_gpe_handler(void *data)
 464 {
 465         acpi_status status = AE_OK;
 466         u32 value;
 467         u8 exec_mode;
 468         struct acpi_ec *ec = (struct acpi_ec *)data;
 469
 470         acpi_clear_gpe(NULL, ec->gpe_bit, ACPI_ISR);
 471         value = acpi_ec_read_status(ec);
 472
 473         if (acpi_ec_mode == EC_INTR) {
 474                 if (acpi_ec_check_status(value, ec->expect_event)) {
 475                         ec->expect_event = 0;
 476                         wake_up(&ec->wait);
 477                 }
 478                 exec_mode = OSL_EC_BURST_HANDLER;
 479         } else {
 480                 exec_mode = OSL_EC_POLL_HANDLER;
 481         }
 482
 483         if (value & ACPI_EC_FLAG_SCI) {
 484                 status = acpi_os_execute(exec_mode, acpi_ec_gpe_query, ec);
 485                 return status == AE_OK ?
 486                     ACPI_INTERRUPT_HANDLED : ACPI_INTERRUPT_NOT_HANDLED;
 487         }
 488         acpi_enable_gpe(NULL, ec->gpe_bit, ACPI_ISR);
 489         return status == AE_OK ?
 490             ACPI_INTERRUPT_HANDLED : ACPI_INTERRUPT_NOT_HANDLED;
 491 }
 492
 493 /* --------------------------------------------------------------------------
 494                              Address Space Management
 495    -------------------------------------------------------------------------- */
 496
 497 static acpi_status
 498 acpi_ec_space_setup(acpi_handle region_handle,
 499                     u32 function, void *handler_context, void **return_context)
 500 {
 501         /*
 502          * The EC object is in the handler context and is needed
 503          * when calling the acpi_ec_space_handler.
 504          */
 505         *return_context = (function != ACPI_REGION_DEACTIVATE) ?
 506             handler_context : NULL;
 507
 508         return AE_OK;
 509 }
 510
 511 static acpi_status
 512 acpi_ec_space_handler(u32 function,
 513                       acpi_physical_address address,
 514                       u32 bit_width,
 515                       acpi_integer * value,
 516                       void *handler_context, void *region_context)
 517 {
 518         int result = 0;
 519         struct acpi_ec *ec = NULL;
 520         u64 temp = *value;
 521         acpi_integer f_v = 0;
 522         int i = 0;
 523
 524
 525         if ((address > 0xFF) || !value || !handler_context)
 526                 return AE_BAD_PARAMETER;
 527
 528         if (bit_width != 8 && acpi_strict) {
 529                 return AE_BAD_PARAMETER;
 530         }
 531
 532         ec = (struct acpi_ec *)handler_context;
 533
 534       next_byte:
 535         switch (function) {
 536         case ACPI_READ:
 537                 temp = 0;
 538                 result = acpi_ec_read(ec, (u8) address, (u32 *) & temp);
 539                 break;
 540         case ACPI_WRITE:
 541                 result = acpi_ec_write(ec, (u8) address, (u8) temp);
 542                 break;
 543         default:
 544                 result = -EINVAL;
 545                 goto out;
 546                 break;
 547         }
 548
 549         bit_width -= 8;
 550         if (bit_width) {
 551                 if (function == ACPI_READ)
 552                         f_v |= temp << 8 * i;
 553                 if (function == ACPI_WRITE)
 554                         temp >>= 8;
 555                 i++;
 556                 address++;
 557                 goto next_byte;
 558         }
 559
 560         if (function == ACPI_READ) {
 561                 f_v |= temp << 8 * i;
 562                 *value = f_v;
 563         }
 564
 565       out:
 566         switch (result) {
 567         case -EINVAL:
 568                 return AE_BAD_PARAMETER;
 569                 break;
 570         case -ENODEV:
 571                 return AE_NOT_FOUND;
 572                 break;
 573         case -ETIME:
 574                 return AE_TIME;
 575                 break;
 576         default:
 577                 return AE_OK;
 578         }
 579 }
 580
 581 /* --------------------------------------------------------------------------
 582                               FS Interface (/proc)
 583    -------------------------------------------------------------------------- */
 584
 585 static struct proc_dir_entry *acpi_ec_dir;
 586
 587 static int acpi_ec_read_info(struct seq_file *seq, void *offset)
 588 {
 589         struct acpi_ec *ec = (struct acpi_ec *)seq->private;
 590
 591
 592         if (!ec)
 593                 goto end;
 594
 595         seq_printf(seq, "gpe bit:                 0x%02x\n",
 596                    (u32) ec->gpe_bit);
 597         seq_printf(seq, "ports:                   0x%02x, 0x%02x\n",
 598                    (u32) ec->status_addr.address,
 599                    (u32) ec->data_addr.address);
 600         seq_printf(seq, "use global lock:         %s\n",
 601                    ec->global_lock ? "yes" : "no");
 602         acpi_enable_gpe(NULL, ec->gpe_bit, ACPI_NOT_ISR);
 603
 604       end:
 605         return 0;
 606 }
 607
 608 static int acpi_ec_info_open_fs(struct inode *inode, struct file *file)
 609 {
 610         return single_open(file, acpi_ec_read_info, PDE(inode)->data);
 611 }
 612
 613 static struct file_operations acpi_ec_info_ops = {
 614         .open = acpi_ec_info_open_fs,
 615         .read = seq_read,
 616         .llseek = seq_lseek,
 617         .release = single_release,
 618         .owner = THIS_MODULE,
 619 };
 620
 621 static int acpi_ec_add_fs(struct acpi_device *device)
 622 {
 623         struct proc_dir_entry *entry = NULL;
 624
 625
 626         if (!acpi_device_dir(device)) {
 627                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
 628                                                      acpi_ec_dir);
 629                 if (!acpi_device_dir(device))
 630                         return -ENODEV;
 631         }
 632
 633         entry = create_proc_entry(ACPI_EC_FILE_INFO, S_IRUGO,
 634                                   acpi_device_dir(device));
 635         if (!entry)
 636                 return -ENODEV;
 637         else {
 638                 entry->proc_fops = &acpi_ec_info_ops;
 639                 entry->data = acpi_driver_data(device);
 640                 entry->owner = THIS_MODULE;
 641         }
 642
 643         return 0;
 644 }
 645
 646 static int acpi_ec_remove_fs(struct acpi_device *device)
 647 {
 648
 649         if (acpi_device_dir(device)) {
 650                 remove_proc_entry(ACPI_EC_FILE_INFO, acpi_device_dir(device));
 651                 remove_proc_entry(acpi_device_bid(device), acpi_ec_dir);
 652                 acpi_device_dir(device) = NULL;
 653         }
 654
 655         return 0;
 656 }
 657
 658 /* --------------------------------------------------------------------------
 659                                Driver Interface
 660    -------------------------------------------------------------------------- */
 661
 662 static int acpi_ec_add(struct acpi_device *device)
 663 {
 664         int result = 0;
 665         acpi_status status = AE_OK;
 666         struct acpi_ec *ec = NULL;
 667
 668
 669         if (!device)
 670                 return -EINVAL;
 671
 672         ec = kmalloc(sizeof(struct acpi_ec), GFP_KERNEL);
 673         if (!ec)
 674                 return -ENOMEM;
 675         memset(ec, 0, sizeof(struct acpi_ec));
 676
 677         ec->handle = device->handle;
 678         ec->uid = -1;
 679         init_MUTEX(&ec->sem);
 680         if (acpi_ec_mode == EC_INTR) {
 681                 atomic_set(&ec->leaving_burst, 1);
 682                 init_waitqueue_head(&ec->wait);
 683         }
 684         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
 685         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
 686         acpi_driver_data(device) = ec;
 687
 688         /* Use the global lock for all EC transactions? */
 689         acpi_evaluate_integer(ec->handle, "_GLK", NULL,
 690                               &ec->global_lock);
 691
 692         /* XXX we don't test uids, because on some boxes ecdt uid = 0, see:
 693            http://bugzilla.kernel.org/show_bug.cgi?id=6111 */
 694         if (ec_ecdt) {
 695                 acpi_remove_address_space_handler(ACPI_ROOT_OBJECT,
 696                                                   ACPI_ADR_SPACE_EC,
 697                                                   &acpi_ec_space_handler);
 698
 699                 acpi_remove_gpe_handler(NULL, ec_ecdt->gpe_bit,
 700                                         &acpi_ec_gpe_handler);
 701
 702                 kfree(ec_ecdt);
 703         }
 704
 705         /* Get GPE bit assignment (EC events). */
 706         /* TODO: Add support for _GPE returning a package */
 707         status =
 708             acpi_evaluate_integer(ec->handle, "_GPE", NULL,
 709                                   &ec->gpe_bit);
 710         if (ACPI_FAILURE(status)) {
 711                 ACPI_EXCEPTION((AE_INFO, status, "Obtaining GPE bit assignment"));
 712                 result = -ENODEV;
 713                 goto end;
 714         }
 715
 716         result = acpi_ec_add_fs(device);
 717         if (result)
 718                 goto end;
 719
 720         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "%s [%s] (gpe %d) interrupt mode.",
 721                acpi_device_name(device), acpi_device_bid(device),
 722                (u32) ec->gpe_bit));
 723
 724         if (!first_ec)
 725                 first_ec = device;
 726
 727   end:
 728         if (result)
 729                 kfree(ec);
 730
 731         return result;
 732 }
 733
 734 static int acpi_ec_remove(struct acpi_device *device, int type)
 735 {
 736         struct acpi_ec *ec = NULL;
 737
 738
 739         if (!device)
 740                 return -EINVAL;
 741
 742         ec = acpi_driver_data(device);
 743
 744         acpi_ec_remove_fs(device);
 745
 746         kfree(ec);
 747
 748         return 0;
 749 }
 750
 751 static acpi_status
 752 acpi_ec_io_ports(struct acpi_resource *resource, void *context)
 753 {
 754         struct acpi_ec *ec = (struct acpi_ec *)context;
 755         struct acpi_generic_address *addr;
 756
 757         if (resource->type != ACPI_RESOURCE_TYPE_IO) {
 758                 return AE_OK;
 759         }
 760
 761         /*
 762          * The first address region returned is the data port, and
 763          * the second address region returned is the status/command
 764          * port.
 765          */
 766         if (ec->data_addr.register_bit_width == 0) {
 767                 addr = &ec->data_addr;
 768         } else if (ec->command_addr.register_bit_width == 0) {
 769                 addr = &ec->command_addr;
 770         } else {
 771                 return AE_CTRL_TERMINATE;
 772         }
 773
 774         addr->address_space_id = ACPI_ADR_SPACE_SYSTEM_IO;
 775         addr->register_bit_width = 8;
 776         addr->register_bit_offset = 0;
 777         addr->address = resource->data.io.minimum;
 778
 779         return AE_OK;
 780 }
 781
 782 static int acpi_ec_start(struct acpi_device *device)
 783 {
 784         acpi_status status = AE_OK;
 785         struct acpi_ec *ec = NULL;
 786
 787
 788         if (!device)
 789                 return -EINVAL;
 790
 791         ec = acpi_driver_data(device);
 792
 793         if (!ec)
 794                 return -EINVAL;
 795
 796         /*
 797          * Get I/O port addresses. Convert to GAS format.
 798          */
 799         status = acpi_walk_resources(ec->handle, METHOD_NAME__CRS,
 800                                      acpi_ec_io_ports, ec);
 801         if (ACPI_FAILURE(status)
 802             || ec->command_addr.register_bit_width == 0) {
 803                 ACPI_EXCEPTION((AE_INFO, status,
 804                                 "Error getting I/O port addresses"));
 805                 return -ENODEV;
 806         }
 807
 808         ec->status_addr = ec->command_addr;
 809
 810         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "gpe=0x%02x, ports=0x%2x,0x%2x",
 811                           (u32) ec->gpe_bit,
 812                           (u32) ec->command_addr.address,
 813                           (u32) ec->data_addr.address));
 814
 815         /*
 816          * Install GPE handler
 817          */
 818         status = acpi_install_gpe_handler(NULL, ec->gpe_bit,
 819                                           ACPI_GPE_EDGE_TRIGGERED,
 820                                           &acpi_ec_gpe_handler, ec);
 821         if (ACPI_FAILURE(status)) {
 822                 return -ENODEV;
 823         }
 824         acpi_set_gpe_type(NULL, ec->gpe_bit, ACPI_GPE_TYPE_RUNTIME);
 825         acpi_enable_gpe(NULL, ec->gpe_bit, ACPI_NOT_ISR);
 826
 827         status = acpi_install_address_space_handler(ec->handle,
 828                                                     ACPI_ADR_SPACE_EC,
 829                                                     &acpi_ec_space_handler,
 830                                                     &acpi_ec_space_setup, ec);
 831         if (ACPI_FAILURE(status)) {
 832                 acpi_remove_gpe_handler(NULL, ec->gpe_bit,
 833                                         &acpi_ec_gpe_handler);
 834                 return -ENODEV;
 835         }
 836
 837         return AE_OK;
 838 }
 839
 840 static int acpi_ec_stop(struct acpi_device *device, int type)
 841 {
 842         acpi_status status = AE_OK;
 843         struct acpi_ec *ec = NULL;
 844
 845
 846         if (!device)
 847                 return -EINVAL;
 848
 849         ec = acpi_driver_data(device);
 850
 851         status = acpi_remove_address_space_handler(ec->handle,
 852                                                    ACPI_ADR_SPACE_EC,
 853                                                    &acpi_ec_space_handler);
 854         if (ACPI_FAILURE(status))
 855                 return -ENODEV;
 856
 857         status =
 858             acpi_remove_gpe_handler(NULL, ec->gpe_bit,
 859                                     &acpi_ec_gpe_handler);
 860         if (ACPI_FAILURE(status))
 861                 return -ENODEV;
 862
 863         return 0;
 864 }
 865
 866 static acpi_status __init
 867 acpi_fake_ecdt_callback(acpi_handle handle,
 868                         u32 Level, void *context, void **retval)
 869 {
 870         acpi_status status;
 871
 872         init_MUTEX(&ec_ecdt->sem);
 873         if (acpi_ec_mode == EC_INTR) {
 874                 init_waitqueue_head(&ec_ecdt->wait);
 875         }
 876         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
 877                                      acpi_ec_io_ports, ec_ecdt);
 878         if (ACPI_FAILURE(status))
 879                 return status;
 880         ec_ecdt->status_addr = ec_ecdt->command_addr;
 881
 882         ec_ecdt->uid = -1;
 883         acpi_evaluate_integer(handle, "_UID", NULL, &ec_ecdt->uid);
 884
 885         status =
 886             acpi_evaluate_integer(handle, "_GPE", NULL,
 887                                   &ec_ecdt->gpe_bit);
 888         if (ACPI_FAILURE(status))
 889                 return status;
 890         ec_ecdt->global_lock = TRUE;
 891         ec_ecdt->handle = handle;
 892
 893         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "GPE=0x%02x, ports=0x%2x, 0x%2x",
 894                (u32) ec_ecdt->gpe_bit,
 895                (u32) ec_ecdt->command_addr.address,
 896                (u32) ec_ecdt->data_addr.address));
 897
 898         return AE_CTRL_TERMINATE;
 899 }
 900
 901 /*
 902  * Some BIOS (such as some from Gateway laptops) access EC region very early
 903  * such as in BAT0._INI or EC._INI before an EC device is found and
 904  * do not provide an ECDT. According to ACPI spec, ECDT isn't mandatorily
 905  * required, but if EC regison is accessed early, it is required.
 906  * The routine tries to workaround the BIOS bug by pre-scan EC device
 907  * It assumes that _CRS, _HID, _GPE, _UID methods of EC don't touch any
 908  * op region (since _REG isn't invoked yet). The assumption is true for
 909  * all systems found.
 910  */
 911 static int __init acpi_ec_fake_ecdt(void)
 912 {
 913         acpi_status status;
 914         int ret = 0;
 915
 916         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Try to make an fake ECDT"));
 917
 918         ec_ecdt = kmalloc(sizeof(struct acpi_ec), GFP_KERNEL);
 919         if (!ec_ecdt) {
 920                 ret = -ENOMEM;
 921                 goto error;
 922         }
 923         memset(ec_ecdt, 0, sizeof(struct acpi_ec));
 924
 925         status = acpi_get_devices(ACPI_EC_HID,
 926                                   acpi_fake_ecdt_callback, NULL, NULL);
 927         if (ACPI_FAILURE(status)) {
 928                 kfree(ec_ecdt);
 929                 ec_ecdt = NULL;
 930                 ret = -ENODEV;
 931                 ACPI_EXCEPTION((AE_INFO, status, "Can't make an fake ECDT"));
 932                 goto error;
 933         }
 934         return 0;
 935   error:
 936         return ret;
 937 }
 938
 939 static int __init acpi_ec_get_real_ecdt(void)
 940 {
 941         acpi_status status;
 942         struct acpi_table_ecdt *ecdt_ptr;
 943
 944         status = acpi_get_firmware_table("ECDT", 1, ACPI_LOGICAL_ADDRESSING,
 945                                          (struct acpi_table_header **)
 946                                          &ecdt_ptr);
 947         if (ACPI_FAILURE(status))
 948                 return -ENODEV;
 949
 950         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found ECDT"));
 951
 952         /*
 953          * Generate a temporary ec context to use until the namespace is scanned
 954          */
 955         ec_ecdt = kmalloc(sizeof(struct acpi_ec), GFP_KERNEL);
 956         if (!ec_ecdt)
 957                 return -ENOMEM;
 958         memset(ec_ecdt, 0, sizeof(struct acpi_ec));
 959
 960         init_MUTEX(&ec_ecdt->sem);
 961         if (acpi_ec_mode == EC_INTR) {
 962                 init_waitqueue_head(&ec_ecdt->wait);
 963         }
 964         ec_ecdt->command_addr = ecdt_ptr->ec_control;
 965         ec_ecdt->status_addr = ecdt_ptr->ec_control;
 966         ec_ecdt->data_addr = ecdt_ptr->ec_data;
 967         ec_ecdt->gpe_bit = ecdt_ptr->gpe_bit;
 968         /* use the GL just to be safe */
 969         ec_ecdt->global_lock = TRUE;
 970         ec_ecdt->uid = ecdt_ptr->uid;
 971
 972         status =
 973             acpi_get_handle(NULL, ecdt_ptr->ec_id, &ec_ecdt->handle);
 974         if (ACPI_FAILURE(status)) {
 975                 goto error;
 976         }
 977
 978         return 0;
 979   error:
 980         ACPI_EXCEPTION((AE_INFO, status, "Could not use ECDT"));
 981         kfree(ec_ecdt);
 982         ec_ecdt = NULL;
 983
 984         return -ENODEV;
 985 }
 986
 987 static int __initdata acpi_fake_ecdt_enabled;
 988 int __init acpi_ec_ecdt_probe(void)
 989 {
 990         acpi_status status;
 991         int ret;
 992
 993         ret = acpi_ec_get_real_ecdt();
 994         /* Try to make a fake ECDT */
 995         if (ret && acpi_fake_ecdt_enabled) {
 996                 ret = acpi_ec_fake_ecdt();
 997         }
 998
 999         if (ret)
1000                 return 0;
1001
1002         /*
1003          * Install GPE handler
1004          */
1005         status = acpi_install_gpe_handler(NULL, ec_ecdt->gpe_bit,
1006                                           ACPI_GPE_EDGE_TRIGGERED,
1007                                           &acpi_ec_gpe_handler, ec_ecdt);
1008         if (ACPI_FAILURE(status)) {
1009                 goto error;
1010         }
1011         acpi_set_gpe_type(NULL, ec_ecdt->gpe_bit, ACPI_GPE_TYPE_RUNTIME);
1012         acpi_enable_gpe(NULL, ec_ecdt->gpe_bit, ACPI_NOT_ISR);
1013
1014         status = acpi_install_address_space_handler(ACPI_ROOT_OBJECT,
1015                                                     ACPI_ADR_SPACE_EC,
1016                                                     &acpi_ec_space_handler,
1017                                                     &acpi_ec_space_setup,
1018                                                     ec_ecdt);
1019         if (ACPI_FAILURE(status)) {
1020                 acpi_remove_gpe_handler(NULL, ec_ecdt->gpe_bit,
1021                                         &acpi_ec_gpe_handler);
1022                 goto error;
1023         }
1024
1025         return 0;
1026
1027       error:
1028         ACPI_EXCEPTION((AE_INFO, status, "Could not use ECDT"));
1029         kfree(ec_ecdt);
1030         ec_ecdt = NULL;
1031
1032         return -ENODEV;
1033 }
1034
1035 static int __init acpi_ec_init(void)
1036 {
1037         int result = 0;
1038
1039
1040         if (acpi_disabled)
1041                 return 0;
1042
1043         acpi_ec_dir = proc_mkdir(ACPI_EC_CLASS, acpi_root_dir);
1044         if (!acpi_ec_dir)
1045                 return -ENODEV;
1046
1047         /* Now register the driver for the EC */
1048         result = acpi_bus_register_driver(&acpi_ec_driver);
1049         if (result < 0) {
1050                 remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1051                 return -ENODEV;
1052         }
1053
1054         return result;
1055 }
1056
1057 subsys_initcall(acpi_ec_init);
1058
1059 /* EC driver currently not unloadable */
1060 #if 0
1061 static void __exit acpi_ec_exit(void)
1062 {
1063
1064         acpi_bus_unregister_driver(&acpi_ec_driver);
1065
1066         remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1067
1068         return;
1069 }
1070 #endif                          /* 0 */
1071
1072 static int __init acpi_fake_ecdt_setup(char *str)
1073 {
1074         acpi_fake_ecdt_enabled = 1;
1075         return 1;
1076 }
1077
1078 __setup("acpi_fake_ecdt", acpi_fake_ecdt_setup);
1079 static int __init acpi_ec_set_intr_mode(char *str)
1080 {
1081         int intr;
1082
1083         if (!get_option(&str, &intr))
1084                 return 0;
1085
1086         if (intr) {
1087                 acpi_ec_mode = EC_INTR;
1088         } else {
1089                 acpi_ec_mode = EC_POLL;
1090         }
1091         acpi_ec_driver.ops.add = acpi_ec_add;
1092         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "EC %s mode.\n", intr ? "interrupt" : "polling"));
1093
1094         return 1;
1095 }
1096
1097 __setup("ec_intr=", acpi_ec_set_intr_mode);