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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("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 #undef PREFIX
  50 #define PREFIX                          "ACPI: EC: "
  51
  52 /* EC status register */
  53 #define ACPI_EC_FLAG_OBF        0x01    /* Output buffer full */
  54 #define ACPI_EC_FLAG_IBF        0x02    /* Input buffer full */
  55 #define ACPI_EC_FLAG_BURST      0x10    /* burst mode */
  56 #define ACPI_EC_FLAG_SCI        0x20    /* EC-SCI occurred */
  57
  58 /* EC commands */
  59 #define ACPI_EC_COMMAND_READ    0x80
  60 #define ACPI_EC_COMMAND_WRITE   0x81
  61 #define ACPI_EC_BURST_ENABLE    0x82
  62 #define ACPI_EC_BURST_DISABLE   0x83
  63 #define ACPI_EC_COMMAND_QUERY   0x84
  64
  65 /* EC events */
  66 enum {
  67         ACPI_EC_EVENT_OBF_1 = 1,        /* Output buffer full */
  68         ACPI_EC_EVENT_IBF_0,            /* Input buffer empty */
  69 };
  70
  71 #define ACPI_EC_DELAY           500     /* Wait 500ms max. during EC ops */
  72 #define ACPI_EC_UDELAY_GLK      1000    /* Wait 1ms max. to get global lock */
  73
  74 enum {
  75         EC_INTR = 1,    /* Output buffer full */
  76         EC_POLL,        /* Input buffer empty */
  77 };
  78
  79 static int acpi_ec_remove(struct acpi_device *device, int type);
  80 static int acpi_ec_start(struct acpi_device *device);
  81 static int acpi_ec_stop(struct acpi_device *device, int type);
  82 static int acpi_ec_add(struct acpi_device *device);
  83
  84 static struct acpi_driver acpi_ec_driver = {
  85         .name = ACPI_EC_DRIVER_NAME,
  86         .class = ACPI_EC_CLASS,
  87         .ids = ACPI_EC_HID,
  88         .ops = {
  89                 .add = acpi_ec_add,
  90                 .remove = acpi_ec_remove,
  91                 .start = acpi_ec_start,
  92                 .stop = acpi_ec_stop,
  93                 },
  94 };
  95
  96 /* If we find an EC via the ECDT, we need to keep a ptr to its context */
  97 struct acpi_ec {
  98         acpi_handle handle;
  99         unsigned long uid;
 100         unsigned long gpe;
 101         unsigned long command_addr;
 102         unsigned long data_addr;
 103         unsigned long global_lock;
 104         struct mutex lock;
 105         atomic_t query_pending;
 106         atomic_t leaving_burst; /* 0 : No, 1 : Yes, 2: abort */
 107         wait_queue_head_t wait;
 108 } *ec_ecdt;
 109
 110 /* External interfaces use first EC only, so remember */
 111 static struct acpi_device *first_ec;
 112 static int acpi_ec_mode = EC_INTR;
 113
 114 /* --------------------------------------------------------------------------
 115                              Transaction Management
 116    -------------------------------------------------------------------------- */
 117
 118 static inline u8 acpi_ec_read_status(struct acpi_ec *ec)
 119 {
 120         return inb(ec->command_addr);
 121 }
 122
 123 static inline u8 acpi_ec_read_data(struct acpi_ec *ec)
 124 {
 125         return inb(ec->data_addr);
 126 }
 127
 128 static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command)
 129 {
 130         outb(command, ec->command_addr);
 131 }
 132
 133 static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data)
 134 {
 135         outb(data, ec->data_addr);
 136 }
 137
 138 static inline int acpi_ec_check_status(struct acpi_ec *ec, u8 event)
 139 {
 140         u8 status = acpi_ec_read_status(ec);
 141
 142         if (event == ACPI_EC_EVENT_OBF_1) {
 143                 if (status & ACPI_EC_FLAG_OBF)
 144                         return 1;
 145         } else if (event == ACPI_EC_EVENT_IBF_0) {
 146                 if (!(status & ACPI_EC_FLAG_IBF))
 147                         return 1;
 148         }
 149
 150         return 0;
 151 }
 152
 153 static int acpi_ec_wait(struct acpi_ec *ec, u8 event)
 154 {
 155         if (acpi_ec_mode == EC_POLL) {
 156                 unsigned long delay = jiffies + msecs_to_jiffies(ACPI_EC_DELAY);
 157                 while (time_before(jiffies, delay)) {
 158                         if (acpi_ec_check_status(ec, event))
 159                                 return 0;
 160                 }
 161         } else {
 162                 if (wait_event_timeout(ec->wait,
 163                                        acpi_ec_check_status(ec, event),
 164                                        msecs_to_jiffies(ACPI_EC_DELAY)) ||
 165                     acpi_ec_check_status(ec, event)) {
 166                         return 0;
 167                 } else {
 168                         printk(KERN_ERR PREFIX "acpi_ec_wait timeout,"
 169                                " status = %d, expect_event = %d\n",
 170                              acpi_ec_read_status(ec), event);
 171                 }
 172         }
 173
 174         return -ETIME;
 175 }
 176
 177 #ifdef ACPI_FUTURE_USAGE
 178 /*
 179  * Note: samsung nv5000 doesn't work with ec burst mode.
 180  * http://bugzilla.kernel.org/show_bug.cgi?id=4980
 181  */
 182 int acpi_ec_enter_burst_mode(struct acpi_ec *ec)
 183 {
 184         u8 tmp = 0;
 185         u8 status = 0;
 186
 187
 188         status = acpi_ec_read_status(ec);
 189         if (status != -EINVAL && !(status & ACPI_EC_FLAG_BURST)) {
 190                 status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0);
 191                 if (status)
 192                         goto end;
 193                 acpi_ec_write_cmd(ec, ACPI_EC_BURST_ENABLE);
 194                 status = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF_1);
 195                 tmp = acpi_ec_read_data(ec);
 196                 if (tmp != 0x90) {      /* Burst ACK byte */
 197                         return -EINVAL;
 198                 }
 199         }
 200
 201         atomic_set(&ec->leaving_burst, 0);
 202         return 0;
 203   end:
 204         ACPI_EXCEPTION((AE_INFO, status, "EC wait, burst mode"));
 205         return -1;
 206 }
 207
 208 int acpi_ec_leave_burst_mode(struct acpi_ec *ec)
 209 {
 210         u8 status = 0;
 211
 212
 213         status = acpi_ec_read_status(ec);
 214         if (status != -EINVAL && (status & ACPI_EC_FLAG_BURST)){
 215                 status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0);
 216                 if(status)
 217                         goto end;
 218                 acpi_ec_write_cmd(ec, ACPI_EC_BURST_DISABLE);
 219                 acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0);
 220         }
 221         atomic_set(&ec->leaving_burst, 1);
 222         return 0;
 223   end:
 224         ACPI_EXCEPTION((AE_INFO, status, "EC leave burst mode"));
 225         return -1;
 226 }
 227 #endif /* ACPI_FUTURE_USAGE */
 228
 229 static int acpi_ec_transaction_unlocked(struct acpi_ec *ec, u8 command,
 230                                         const u8 *wdata, unsigned wdata_len,
 231                                         u8 *rdata, unsigned rdata_len)
 232 {
 233         int result = 0;
 234
 235         acpi_ec_write_cmd(ec, command);
 236
 237         for (; wdata_len > 0; --wdata_len) {
 238                 result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0);
 239                 if (result) {
 240                         printk(KERN_ERR PREFIX "write_cmd timeout, command = %d\n",
 241                              command);
 242                         goto end;
 243                 }
 244                 acpi_ec_write_data(ec, *(wdata++));
 245         }
 246
 247         if (!rdata_len) {
 248                 result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0);
 249                 if (result) {
 250                         printk(KERN_ERR PREFIX "finish-write timeout, command = %d\n",
 251                              command);
 252                         goto end;
 253                 }
 254         } else if (command == ACPI_EC_COMMAND_QUERY) {
 255                 atomic_set(&ec->query_pending, 0);
 256         }
 257
 258         for (; rdata_len > 0; --rdata_len) {
 259                 result = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF_1);
 260                 if (result) {
 261                         printk(KERN_ERR PREFIX "read timeout, command = %d\n",
 262                              command);
 263                         goto end;
 264                 }
 265
 266                 *(rdata++) = acpi_ec_read_data(ec);
 267         }
 268       end:
 269         return result;
 270 }
 271
 272 static int acpi_ec_transaction(struct acpi_ec *ec, u8 command,
 273                                 const u8 *wdata, unsigned wdata_len,
 274                                 u8 *rdata, unsigned rdata_len)
 275 {
 276         int status;
 277         u32 glk;
 278
 279         if (!ec || (wdata_len && !wdata) || (rdata_len && !rdata))
 280                 return -EINVAL;
 281
 282         if (rdata)
 283                 memset(rdata, 0, rdata_len);
 284
 285         mutex_lock(&ec->lock);
 286         if (ec->global_lock) {
 287                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 288                 if (ACPI_FAILURE(status))
 289                         return -ENODEV;
 290         }
 291
 292         /* Make sure GPE is enabled before doing transaction */
 293         acpi_enable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
 294
 295         status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0);
 296         if (status) {
 297                 printk(KERN_DEBUG PREFIX "read EC, IB not empty\n");
 298                 goto end;
 299         }
 300
 301         status = acpi_ec_transaction_unlocked(ec, command,
 302                                               wdata, wdata_len,
 303                                               rdata, rdata_len);
 304
 305 end:
 306
 307         if (ec->global_lock)
 308                 acpi_release_global_lock(glk);
 309         mutex_unlock(&ec->lock);
 310
 311         return status;
 312 }
 313
 314 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 *data)
 315 {
 316         int result;
 317         u8 d;
 318
 319         result = acpi_ec_transaction(ec, ACPI_EC_COMMAND_READ,
 320                                      &address, 1, &d, 1);
 321         *data = d;
 322         return result;
 323 }
 324
 325 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
 326 {
 327         u8 wdata[2] = { address, data };
 328         return acpi_ec_transaction(ec, ACPI_EC_COMMAND_WRITE,
 329                                    wdata, 2, NULL, 0);
 330 }
 331
 332 /*
 333  * Externally callable EC access functions. For now, assume 1 EC only
 334  */
 335 int ec_read(u8 addr, u8 *val)
 336 {
 337         struct acpi_ec *ec;
 338         int err;
 339         u8 temp_data;
 340
 341         if (!first_ec)
 342                 return -ENODEV;
 343
 344         ec = acpi_driver_data(first_ec);
 345
 346         err = acpi_ec_read(ec, addr, &temp_data);
 347
 348         if (!err) {
 349                 *val = temp_data;
 350                 return 0;
 351         } else
 352                 return err;
 353 }
 354
 355 EXPORT_SYMBOL(ec_read);
 356
 357 int ec_write(u8 addr, u8 val)
 358 {
 359         struct acpi_ec *ec;
 360         int err;
 361
 362         if (!first_ec)
 363                 return -ENODEV;
 364
 365         ec = acpi_driver_data(first_ec);
 366
 367         err = acpi_ec_write(ec, addr, val);
 368
 369         return err;
 370 }
 371
 372 EXPORT_SYMBOL(ec_write);
 373
 374 extern int ec_transaction(u8 command,
 375                           const u8 *wdata, unsigned wdata_len,
 376                           u8 *rdata, unsigned rdata_len)
 377 {
 378         struct acpi_ec *ec;
 379
 380         if (!first_ec)
 381                 return -ENODEV;
 382
 383         ec = acpi_driver_data(first_ec);
 384
 385         return acpi_ec_transaction(ec, command, wdata,
 386                                    wdata_len, rdata, rdata_len);
 387 }
 388
 389 EXPORT_SYMBOL(ec_transaction);
 390
 391 static int acpi_ec_query(struct acpi_ec *ec, u8 *data)
 392 {
 393         int result;
 394         u8 d;
 395
 396         if (!ec || !data)
 397                 return -EINVAL;
 398
 399         /*
 400          * Query the EC to find out which _Qxx method we need to evaluate.
 401          * Note that successful completion of the query causes the ACPI_EC_SCI
 402          * bit to be cleared (and thus clearing the interrupt source).
 403          */
 404
 405         result = acpi_ec_transaction(ec, ACPI_EC_COMMAND_QUERY, NULL, 0, &d, 1);
 406         if (result)
 407                 return result;
 408
 409         if (!d)
 410                 return -ENODATA;
 411
 412         *data = d;
 413         return 0;
 414 }
 415
 416 /* --------------------------------------------------------------------------
 417                                 Event Management
 418    -------------------------------------------------------------------------- */
 419
 420 static void acpi_ec_gpe_query(void *ec_cxt)
 421 {
 422         struct acpi_ec *ec = (struct acpi_ec *)ec_cxt;
 423         u8 value = 0;
 424         char object_name[8];
 425
 426         if (!ec || acpi_ec_query(ec, &value))
 427                 return;
 428
 429         snprintf(object_name, 8, "_Q%2.2X", value);
 430
 431         printk(KERN_INFO PREFIX "evaluating %s\n", object_name);
 432
 433         acpi_evaluate_object(ec->handle, object_name, NULL, NULL);
 434 }
 435
 436 static u32 acpi_ec_gpe_handler(void *data)
 437 {
 438         acpi_status status = AE_OK;
 439         u8 value;
 440         struct acpi_ec *ec = (struct acpi_ec *)data;
 441
 442
 443         if (acpi_ec_mode == EC_INTR) {
 444                 wake_up(&ec->wait);
 445         }
 446
 447         value = acpi_ec_read_status(ec);
 448         if ((value & ACPI_EC_FLAG_SCI) && !atomic_read(&ec->query_pending)) {
 449                 atomic_set(&ec->query_pending, 1);
 450                 status = acpi_os_execute(OSL_EC_BURST_HANDLER, acpi_ec_gpe_query, ec);
 451         }
 452
 453         return status == AE_OK ?
 454             ACPI_INTERRUPT_HANDLED : ACPI_INTERRUPT_NOT_HANDLED;
 455 }
 456
 457 /* --------------------------------------------------------------------------
 458                              Address Space Management
 459    -------------------------------------------------------------------------- */
 460
 461 static acpi_status
 462 acpi_ec_space_setup(acpi_handle region_handle,
 463                     u32 function, void *handler_context, void **return_context)
 464 {
 465         /*
 466          * The EC object is in the handler context and is needed
 467          * when calling the acpi_ec_space_handler.
 468          */
 469         *return_context = (function != ACPI_REGION_DEACTIVATE) ?
 470             handler_context : NULL;
 471
 472         return AE_OK;
 473 }
 474
 475 static acpi_status
 476 acpi_ec_space_handler(u32 function,
 477                       acpi_physical_address address,
 478                       u32 bit_width,
 479                       acpi_integer * value,
 480                       void *handler_context, void *region_context)
 481 {
 482         int result = 0;
 483         struct acpi_ec *ec = NULL;
 484         u64 temp = *value;
 485         acpi_integer f_v = 0;
 486         int i = 0;
 487
 488
 489         if ((address > 0xFF) || !value || !handler_context)
 490                 return AE_BAD_PARAMETER;
 491
 492         if (bit_width != 8 && acpi_strict) {
 493                 return AE_BAD_PARAMETER;
 494         }
 495
 496         ec = (struct acpi_ec *)handler_context;
 497
 498       next_byte:
 499         switch (function) {
 500         case ACPI_READ:
 501                 temp = 0;
 502                 result = acpi_ec_read(ec, (u8) address, (u8 *) &temp);
 503                 break;
 504         case ACPI_WRITE:
 505                 result = acpi_ec_write(ec, (u8) address, (u8) temp);
 506                 break;
 507         default:
 508                 result = -EINVAL;
 509                 goto out;
 510                 break;
 511         }
 512
 513         bit_width -= 8;
 514         if (bit_width) {
 515                 if (function == ACPI_READ)
 516                         f_v |= temp << 8 * i;
 517                 if (function == ACPI_WRITE)
 518                         temp >>= 8;
 519                 i++;
 520                 address++;
 521                 goto next_byte;
 522         }
 523
 524         if (function == ACPI_READ) {
 525                 f_v |= temp << 8 * i;
 526                 *value = f_v;
 527         }
 528
 529       out:
 530         switch (result) {
 531         case -EINVAL:
 532                 return AE_BAD_PARAMETER;
 533                 break;
 534         case -ENODEV:
 535                 return AE_NOT_FOUND;
 536                 break;
 537         case -ETIME:
 538                 return AE_TIME;
 539                 break;
 540         default:
 541                 return AE_OK;
 542         }
 543 }
 544
 545 /* --------------------------------------------------------------------------
 546                               FS Interface (/proc)
 547    -------------------------------------------------------------------------- */
 548
 549 static struct proc_dir_entry *acpi_ec_dir;
 550
 551 static int acpi_ec_read_info(struct seq_file *seq, void *offset)
 552 {
 553         struct acpi_ec *ec = (struct acpi_ec *)seq->private;
 554
 555
 556         if (!ec)
 557                 goto end;
 558
 559         seq_printf(seq, "gpe:                 0x%02x\n",
 560                    (u32) ec->gpe);
 561         seq_printf(seq, "ports:                   0x%02x, 0x%02x\n",
 562                    (u32) ec->command_addr,
 563                    (u32) ec->data_addr);
 564         seq_printf(seq, "use global lock:         %s\n",
 565                    ec->global_lock ? "yes" : "no");
 566         acpi_enable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
 567
 568       end:
 569         return 0;
 570 }
 571
 572 static int acpi_ec_info_open_fs(struct inode *inode, struct file *file)
 573 {
 574         return single_open(file, acpi_ec_read_info, PDE(inode)->data);
 575 }
 576
 577 static struct file_operations acpi_ec_info_ops = {
 578         .open = acpi_ec_info_open_fs,
 579         .read = seq_read,
 580         .llseek = seq_lseek,
 581         .release = single_release,
 582         .owner = THIS_MODULE,
 583 };
 584
 585 static int acpi_ec_add_fs(struct acpi_device *device)
 586 {
 587         struct proc_dir_entry *entry = NULL;
 588
 589
 590         if (!acpi_device_dir(device)) {
 591                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
 592                                                      acpi_ec_dir);
 593                 if (!acpi_device_dir(device))
 594                         return -ENODEV;
 595         }
 596
 597         entry = create_proc_entry(ACPI_EC_FILE_INFO, S_IRUGO,
 598                                   acpi_device_dir(device));
 599         if (!entry)
 600                 return -ENODEV;
 601         else {
 602                 entry->proc_fops = &acpi_ec_info_ops;
 603                 entry->data = acpi_driver_data(device);
 604                 entry->owner = THIS_MODULE;
 605         }
 606
 607         return 0;
 608 }
 609
 610 static int acpi_ec_remove_fs(struct acpi_device *device)
 611 {
 612
 613         if (acpi_device_dir(device)) {
 614                 remove_proc_entry(ACPI_EC_FILE_INFO, acpi_device_dir(device));
 615                 remove_proc_entry(acpi_device_bid(device), acpi_ec_dir);
 616                 acpi_device_dir(device) = NULL;
 617         }
 618
 619         return 0;
 620 }
 621
 622 /* --------------------------------------------------------------------------
 623                                Driver Interface
 624    -------------------------------------------------------------------------- */
 625
 626 static int acpi_ec_add(struct acpi_device *device)
 627 {
 628         int result = 0;
 629         acpi_status status = AE_OK;
 630         struct acpi_ec *ec = NULL;
 631
 632
 633         if (!device)
 634                 return -EINVAL;
 635
 636         ec = kmalloc(sizeof(struct acpi_ec), GFP_KERNEL);
 637         if (!ec)
 638                 return -ENOMEM;
 639         memset(ec, 0, sizeof(struct acpi_ec));
 640
 641         ec->handle = device->handle;
 642         ec->uid = -1;
 643         mutex_init(&ec->lock);
 644         atomic_set(&ec->query_pending, 0);
 645         if (acpi_ec_mode == EC_INTR) {
 646                 atomic_set(&ec->leaving_burst, 1);
 647                 init_waitqueue_head(&ec->wait);
 648         }
 649         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
 650         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
 651         acpi_driver_data(device) = ec;
 652
 653         /* Use the global lock for all EC transactions? */
 654         acpi_evaluate_integer(ec->handle, "_GLK", NULL,
 655                               &ec->global_lock);
 656
 657         /* XXX we don't test uids, because on some boxes ecdt uid = 0, see:
 658            http://bugzilla.kernel.org/show_bug.cgi?id=6111 */
 659         if (ec_ecdt) {
 660                 acpi_remove_address_space_handler(ACPI_ROOT_OBJECT,
 661                                                   ACPI_ADR_SPACE_EC,
 662                                                   &acpi_ec_space_handler);
 663
 664                 acpi_remove_gpe_handler(NULL, ec_ecdt->gpe,
 665                                         &acpi_ec_gpe_handler);
 666
 667                 kfree(ec_ecdt);
 668         }
 669
 670         /* Get GPE bit assignment (EC events). */
 671         /* TODO: Add support for _GPE returning a package */
 672         status =
 673             acpi_evaluate_integer(ec->handle, "_GPE", NULL,
 674                                   &ec->gpe);
 675         if (ACPI_FAILURE(status)) {
 676                 ACPI_EXCEPTION((AE_INFO, status, "Obtaining GPE bit assignment"));
 677                 result = -ENODEV;
 678                 goto end;
 679         }
 680
 681         result = acpi_ec_add_fs(device);
 682         if (result)
 683                 goto end;
 684
 685         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "%s [%s] (gpe %d) interrupt mode.",
 686                acpi_device_name(device), acpi_device_bid(device),
 687                (u32) ec->gpe));
 688
 689         if (!first_ec)
 690                 first_ec = device;
 691
 692   end:
 693         if (result)
 694                 kfree(ec);
 695
 696         return result;
 697 }
 698
 699 static int acpi_ec_remove(struct acpi_device *device, int type)
 700 {
 701         struct acpi_ec *ec = NULL;
 702
 703
 704         if (!device)
 705                 return -EINVAL;
 706
 707         ec = acpi_driver_data(device);
 708
 709         acpi_ec_remove_fs(device);
 710
 711         kfree(ec);
 712
 713         return 0;
 714 }
 715
 716 static acpi_status
 717 acpi_ec_io_ports(struct acpi_resource *resource, void *context)
 718 {
 719         struct acpi_ec *ec = (struct acpi_ec *)context;
 720
 721         if (resource->type != ACPI_RESOURCE_TYPE_IO) {
 722                 return AE_OK;
 723         }
 724
 725         /*
 726          * The first address region returned is the data port, and
 727          * the second address region returned is the status/command
 728          * port.
 729          */
 730         if (ec->data_addr == 0) {
 731                 ec->data_addr = resource->data.io.minimum;
 732         } else if (ec->command_addr == 0) {
 733                 ec->command_addr = resource->data.io.minimum;
 734         } else {
 735                 return AE_CTRL_TERMINATE;
 736         }
 737
 738         return AE_OK;
 739 }
 740
 741 static int acpi_ec_start(struct acpi_device *device)
 742 {
 743         acpi_status status = AE_OK;
 744         struct acpi_ec *ec = NULL;
 745
 746
 747         if (!device)
 748                 return -EINVAL;
 749
 750         ec = acpi_driver_data(device);
 751
 752         if (!ec)
 753                 return -EINVAL;
 754
 755         /*
 756          * Get I/O port addresses. Convert to GAS format.
 757          */
 758         status = acpi_walk_resources(ec->handle, METHOD_NAME__CRS,
 759                                      acpi_ec_io_ports, ec);
 760         if (ACPI_FAILURE(status) || ec->command_addr == 0) {
 761                 ACPI_EXCEPTION((AE_INFO, status,
 762                                 "Error getting I/O port addresses"));
 763                 return -ENODEV;
 764         }
 765
 766         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "gpe=0x%02lx, ports=0x%2lx,0x%2lx",
 767                           ec->gpe, ec->command_addr, ec->data_addr));
 768
 769         /*
 770          * Install GPE handler
 771          */
 772         status = acpi_install_gpe_handler(NULL, ec->gpe,
 773                                           ACPI_GPE_EDGE_TRIGGERED,
 774                                           &acpi_ec_gpe_handler, ec);
 775         if (ACPI_FAILURE(status)) {
 776                 return -ENODEV;
 777         }
 778         acpi_set_gpe_type(NULL, ec->gpe, ACPI_GPE_TYPE_RUNTIME);
 779         acpi_enable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
 780
 781         status = acpi_install_address_space_handler(ec->handle,
 782                                                     ACPI_ADR_SPACE_EC,
 783                                                     &acpi_ec_space_handler,
 784                                                     &acpi_ec_space_setup, ec);
 785         if (ACPI_FAILURE(status)) {
 786                 acpi_remove_gpe_handler(NULL, ec->gpe,
 787                                         &acpi_ec_gpe_handler);
 788                 return -ENODEV;
 789         }
 790
 791         return AE_OK;
 792 }
 793
 794 static int acpi_ec_stop(struct acpi_device *device, int type)
 795 {
 796         acpi_status status = AE_OK;
 797         struct acpi_ec *ec = NULL;
 798
 799
 800         if (!device)
 801                 return -EINVAL;
 802
 803         ec = acpi_driver_data(device);
 804
 805         status = acpi_remove_address_space_handler(ec->handle,
 806                                                    ACPI_ADR_SPACE_EC,
 807                                                    &acpi_ec_space_handler);
 808         if (ACPI_FAILURE(status))
 809                 return -ENODEV;
 810
 811         status =
 812             acpi_remove_gpe_handler(NULL, ec->gpe,
 813                                     &acpi_ec_gpe_handler);
 814         if (ACPI_FAILURE(status))
 815                 return -ENODEV;
 816
 817         return 0;
 818 }
 819
 820 static acpi_status __init
 821 acpi_fake_ecdt_callback(acpi_handle handle,
 822                         u32 Level, void *context, void **retval)
 823 {
 824         acpi_status status;
 825
 826         mutex_init(&ec_ecdt->lock);
 827         if (acpi_ec_mode == EC_INTR) {
 828                 init_waitqueue_head(&ec_ecdt->wait);
 829         }
 830         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
 831                                      acpi_ec_io_ports, ec_ecdt);
 832         if (ACPI_FAILURE(status))
 833                 return status;
 834
 835         ec_ecdt->uid = -1;
 836         acpi_evaluate_integer(handle, "_UID", NULL, &ec_ecdt->uid);
 837
 838         status =
 839             acpi_evaluate_integer(handle, "_GPE", NULL,
 840                                   &ec_ecdt->gpe);
 841         if (ACPI_FAILURE(status))
 842                 return status;
 843         ec_ecdt->global_lock = TRUE;
 844         ec_ecdt->handle = handle;
 845
 846         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "GPE=0x%02lx, ports=0x%2lx, 0x%2lx",
 847                ec_ecdt->gpe, ec_ecdt->command_addr, ec_ecdt->data_addr));
 848
 849         return AE_CTRL_TERMINATE;
 850 }
 851
 852 /*
 853  * Some BIOS (such as some from Gateway laptops) access EC region very early
 854  * such as in BAT0._INI or EC._INI before an EC device is found and
 855  * do not provide an ECDT. According to ACPI spec, ECDT isn't mandatorily
 856  * required, but if EC regison is accessed early, it is required.
 857  * The routine tries to workaround the BIOS bug by pre-scan EC device
 858  * It assumes that _CRS, _HID, _GPE, _UID methods of EC don't touch any
 859  * op region (since _REG isn't invoked yet). The assumption is true for
 860  * all systems found.
 861  */
 862 static int __init acpi_ec_fake_ecdt(void)
 863 {
 864         acpi_status status;
 865         int ret = 0;
 866
 867         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Try to make an fake ECDT"));
 868
 869         ec_ecdt = kmalloc(sizeof(struct acpi_ec), GFP_KERNEL);
 870         if (!ec_ecdt) {
 871                 ret = -ENOMEM;
 872                 goto error;
 873         }
 874         memset(ec_ecdt, 0, sizeof(struct acpi_ec));
 875
 876         status = acpi_get_devices(ACPI_EC_HID,
 877                                   acpi_fake_ecdt_callback, NULL, NULL);
 878         if (ACPI_FAILURE(status)) {
 879                 kfree(ec_ecdt);
 880                 ec_ecdt = NULL;
 881                 ret = -ENODEV;
 882                 ACPI_EXCEPTION((AE_INFO, status, "Can't make an fake ECDT"));
 883                 goto error;
 884         }
 885         return 0;
 886   error:
 887         return ret;
 888 }
 889
 890 static int __init acpi_ec_get_real_ecdt(void)
 891 {
 892         acpi_status status;
 893         struct acpi_table_ecdt *ecdt_ptr;
 894
 895         status = acpi_get_firmware_table("ECDT", 1, ACPI_LOGICAL_ADDRESSING,
 896                                          (struct acpi_table_header **)
 897                                          &ecdt_ptr);
 898         if (ACPI_FAILURE(status))
 899                 return -ENODEV;
 900
 901         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found ECDT"));
 902
 903         /*
 904          * Generate a temporary ec context to use until the namespace is scanned
 905          */
 906         ec_ecdt = kmalloc(sizeof(struct acpi_ec), GFP_KERNEL);
 907         if (!ec_ecdt)
 908                 return -ENOMEM;
 909         memset(ec_ecdt, 0, sizeof(struct acpi_ec));
 910
 911         mutex_init(&ec_ecdt->lock);
 912         if (acpi_ec_mode == EC_INTR) {
 913                 init_waitqueue_head(&ec_ecdt->wait);
 914         }
 915         ec_ecdt->command_addr = ecdt_ptr->ec_control.address;
 916         ec_ecdt->data_addr = ecdt_ptr->ec_data.address;
 917         ec_ecdt->gpe = ecdt_ptr->gpe_bit;
 918         /* use the GL just to be safe */
 919         ec_ecdt->global_lock = TRUE;
 920         ec_ecdt->uid = ecdt_ptr->uid;
 921
 922         status =
 923             acpi_get_handle(NULL, ecdt_ptr->ec_id, &ec_ecdt->handle);
 924         if (ACPI_FAILURE(status)) {
 925                 goto error;
 926         }
 927
 928         return 0;
 929   error:
 930         ACPI_EXCEPTION((AE_INFO, status, "Could not use ECDT"));
 931         kfree(ec_ecdt);
 932         ec_ecdt = NULL;
 933
 934         return -ENODEV;
 935 }
 936
 937 static int __initdata acpi_fake_ecdt_enabled;
 938 int __init acpi_ec_ecdt_probe(void)
 939 {
 940         acpi_status status;
 941         int ret;
 942
 943         ret = acpi_ec_get_real_ecdt();
 944         /* Try to make a fake ECDT */
 945         if (ret && acpi_fake_ecdt_enabled) {
 946                 ret = acpi_ec_fake_ecdt();
 947         }
 948
 949         if (ret)
 950                 return 0;
 951
 952         /*
 953          * Install GPE handler
 954          */
 955         status = acpi_install_gpe_handler(NULL, ec_ecdt->gpe,
 956                                           ACPI_GPE_EDGE_TRIGGERED,
 957                                           &acpi_ec_gpe_handler, ec_ecdt);
 958         if (ACPI_FAILURE(status)) {
 959                 goto error;
 960         }
 961         acpi_set_gpe_type(NULL, ec_ecdt->gpe, ACPI_GPE_TYPE_RUNTIME);
 962         acpi_enable_gpe(NULL, ec_ecdt->gpe, ACPI_NOT_ISR);
 963
 964         status = acpi_install_address_space_handler(ACPI_ROOT_OBJECT,
 965                                                     ACPI_ADR_SPACE_EC,
 966                                                     &acpi_ec_space_handler,
 967                                                     &acpi_ec_space_setup,
 968                                                     ec_ecdt);
 969         if (ACPI_FAILURE(status)) {
 970                 acpi_remove_gpe_handler(NULL, ec_ecdt->gpe,
 971                                         &acpi_ec_gpe_handler);
 972                 goto error;
 973         }
 974
 975         return 0;
 976
 977       error:
 978         ACPI_EXCEPTION((AE_INFO, status, "Could not use ECDT"));
 979         kfree(ec_ecdt);
 980         ec_ecdt = NULL;
 981
 982         return -ENODEV;
 983 }
 984
 985 static int __init acpi_ec_init(void)
 986 {
 987         int result = 0;
 988
 989
 990         if (acpi_disabled)
 991                 return 0;
 992
 993         acpi_ec_dir = proc_mkdir(ACPI_EC_CLASS, acpi_root_dir);
 994         if (!acpi_ec_dir)
 995                 return -ENODEV;
 996
 997         /* Now register the driver for the EC */
 998         result = acpi_bus_register_driver(&acpi_ec_driver);
 999         if (result < 0) {
1000                 remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1001                 return -ENODEV;
1002         }
1003
1004         return result;
1005 }
1006
1007 subsys_initcall(acpi_ec_init);
1008
1009 /* EC driver currently not unloadable */
1010 #if 0
1011 static void __exit acpi_ec_exit(void)
1012 {
1013
1014         acpi_bus_unregister_driver(&acpi_ec_driver);
1015
1016         remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1017
1018         return;
1019 }
1020 #endif                          /* 0 */
1021
1022 static int __init acpi_fake_ecdt_setup(char *str)
1023 {
1024         acpi_fake_ecdt_enabled = 1;
1025         return 1;
1026 }
1027
1028 __setup("acpi_fake_ecdt", acpi_fake_ecdt_setup);
1029 static int __init acpi_ec_set_intr_mode(char *str)
1030 {
1031         int intr;
1032
1033         if (!get_option(&str, &intr))
1034                 return 0;
1035
1036         if (intr) {
1037                 acpi_ec_mode = EC_INTR;
1038         } else {
1039                 acpi_ec_mode = EC_POLL;
1040         }
1041         acpi_ec_driver.ops.add = acpi_ec_add;
1042         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "EC %s mode.\n", intr ? "interrupt" : "polling"));
1043
1044         return 1;
1045 }
1046
1047 __setup("ec_intr=", acpi_ec_set_intr_mode);