drivers/acpi/ec.c

   1 /*
   2  *  acpi_ec.c - ACPI Embedded Controller Driver ($Revision: 38 $)
   3  *
   4  *  Copyright (C) 2004 Luming Yu <luming.yu@intel.com>
   5  *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
   6  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
   7  *
   8  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   9  *
  10  *  This program is free software; you can redistribute it and/or modify
  11  *  it under the terms of the GNU General Public License as published by
  12  *  the Free Software Foundation; either version 2 of the License, or (at
  13  *  your option) any later version.
  14  *
  15  *  This program is distributed in the hope that it will be useful, but
  16  *  WITHOUT ANY WARRANTY; without even the implied warranty of
  17  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  18  *  General Public License for more details.
  19  *
  20  *  You should have received a copy of the GNU General Public License along
  21  *  with this program; if not, write to the Free Software Foundation, Inc.,
  22  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
  23  *
  24  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  25  */
  26
  27 #include <linux/kernel.h>
  28 #include <linux/module.h>
  29 #include <linux/init.h>
  30 #include <linux/types.h>
  31 #include <linux/delay.h>
  32 #include <linux/proc_fs.h>
  33 #include <linux/seq_file.h>
  34 #include <linux/interrupt.h>
  35 #include <asm/io.h>
  36 #include <acpi/acpi_bus.h>
  37 #include <acpi/acpi_drivers.h>
  38 #include <acpi/actypes.h>
  39
  40 #define _COMPONENT              ACPI_EC_COMPONENT
  41 ACPI_MODULE_NAME("ec");
  42 #define ACPI_EC_COMPONENT               0x00100000
  43 #define ACPI_EC_CLASS                   "embedded_controller"
  44 #define ACPI_EC_HID                     "PNP0C09"
  45 #define ACPI_EC_DEVICE_NAME             "Embedded Controller"
  46 #define ACPI_EC_FILE_INFO               "info"
  47 #undef PREFIX
  48 #define PREFIX                          "ACPI: EC: "
  49 /* EC status register */
  50 #define ACPI_EC_FLAG_OBF        0x01    /* Output buffer full */
  51 #define ACPI_EC_FLAG_IBF        0x02    /* Input buffer full */
  52 #define ACPI_EC_FLAG_BURST      0x10    /* burst mode */
  53 #define ACPI_EC_FLAG_SCI        0x20    /* EC-SCI occurred */
  54 /* EC commands */
  55 enum ec_command {
  56         ACPI_EC_COMMAND_READ = 0x80,
  57         ACPI_EC_COMMAND_WRITE = 0x81,
  58         ACPI_EC_BURST_ENABLE = 0x82,
  59         ACPI_EC_BURST_DISABLE = 0x83,
  60         ACPI_EC_COMMAND_QUERY = 0x84,
  61 };
  62 /* EC events */
  63 enum ec_event {
  64         ACPI_EC_EVENT_OBF_1 = 1,        /* Output buffer full */
  65         ACPI_EC_EVENT_IBF_0,    /* Input buffer empty */
  66 };
  67
  68 #define ACPI_EC_DELAY           500     /* Wait 500ms max. during EC ops */
  69 #define ACPI_EC_UDELAY_GLK      1000    /* Wait 1ms max. to get global lock */
  70
  71 static enum ec_mode {
  72         EC_INTR = 1,            /* Output buffer full */
  73         EC_POLL,                /* Input buffer empty */
  74 } acpi_ec_mode = EC_INTR;
  75
  76 static int acpi_ec_remove(struct acpi_device *device, int type);
  77 static int acpi_ec_start(struct acpi_device *device);
  78 static int acpi_ec_stop(struct acpi_device *device, int type);
  79 static int acpi_ec_add(struct acpi_device *device);
  80
  81 static struct acpi_driver acpi_ec_driver = {
  82         .name = "ec",
  83         .class = ACPI_EC_CLASS,
  84         .ids = ACPI_EC_HID,
  85         .ops = {
  86                 .add = acpi_ec_add,
  87                 .remove = acpi_ec_remove,
  88                 .start = acpi_ec_start,
  89                 .stop = acpi_ec_stop,
  90                 },
  91 };
  92
  93 /* If we find an EC via the ECDT, we need to keep a ptr to its context */
  94 static struct acpi_ec {
  95         acpi_handle handle;
  96         unsigned long uid;
  97         unsigned long gpe;
  98         unsigned long command_addr;
  99         unsigned long data_addr;
 100         unsigned long global_lock;
 101         struct mutex lock;
 102         atomic_t query_pending;
 103         atomic_t event_count;
 104         wait_queue_head_t wait;
 105 } *ec_ecdt;
 106
 107 /* External interfaces use first EC only, so remember */
 108 static struct acpi_device *first_ec;
 109
 110 /* --------------------------------------------------------------------------
 111                              Transaction Management
 112    -------------------------------------------------------------------------- */
 113
 114 static inline u8 acpi_ec_read_status(struct acpi_ec *ec)
 115 {
 116         return inb(ec->command_addr);
 117 }
 118
 119 static inline u8 acpi_ec_read_data(struct acpi_ec *ec)
 120 {
 121         return inb(ec->data_addr);
 122 }
 123
 124 static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command)
 125 {
 126         outb(command, ec->command_addr);
 127 }
 128
 129 static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data)
 130 {
 131         outb(data, ec->data_addr);
 132 }
 133
 134 static inline int acpi_ec_check_status(struct acpi_ec *ec, enum ec_event event,
 135                                        unsigned old_count)
 136 {
 137         u8 status = acpi_ec_read_status(ec);
 138         if (old_count == atomic_read(&ec->event_count))
 139                 return 0;
 140         if (event == ACPI_EC_EVENT_OBF_1) {
 141                 if (status & ACPI_EC_FLAG_OBF)
 142                         return 1;
 143         } else if (event == ACPI_EC_EVENT_IBF_0) {
 144                 if (!(status & ACPI_EC_FLAG_IBF))
 145                         return 1;
 146         }
 147
 148         return 0;
 149 }
 150
 151 static int acpi_ec_wait(struct acpi_ec *ec, enum ec_event event, unsigned count)
 152 {
 153         if (acpi_ec_mode == EC_POLL) {
 154                 unsigned long delay = jiffies + msecs_to_jiffies(ACPI_EC_DELAY);
 155                 while (time_before(jiffies, delay)) {
 156                         if (acpi_ec_check_status(ec, event, 0))
 157                                 return 0;
 158                 }
 159         } else {
 160                 if (wait_event_timeout(ec->wait,
 161                                        acpi_ec_check_status(ec, event, count),
 162                                        msecs_to_jiffies(ACPI_EC_DELAY)) ||
 163                     acpi_ec_check_status(ec, event, 0)) {
 164                         return 0;
 165                 } else {
 166                         printk(KERN_ERR PREFIX "acpi_ec_wait timeout,"
 167                                " status = %d, expect_event = %d\n",
 168                                acpi_ec_read_status(ec), event);
 169                 }
 170         }
 171
 172         return -ETIME;
 173 }
 174
 175 static int acpi_ec_transaction_unlocked(struct acpi_ec *ec, u8 command,
 176                                         const u8 * wdata, unsigned wdata_len,
 177                                         u8 * rdata, unsigned rdata_len)
 178 {
 179         int result = 0;
 180         unsigned count = atomic_read(&ec->event_count);
 181         acpi_ec_write_cmd(ec, command);
 182
 183         for (; wdata_len > 0; --wdata_len) {
 184                 result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0, count);
 185                 if (result) {
 186                         printk(KERN_ERR PREFIX
 187                                "write_cmd timeout, command = %d\n", command);
 188                         goto end;
 189                 }
 190                 count = atomic_read(&ec->event_count);
 191                 acpi_ec_write_data(ec, *(wdata++));
 192         }
 193
 194         if (!rdata_len) {
 195                 result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0, count);
 196                 if (result) {
 197                         printk(KERN_ERR PREFIX
 198                                "finish-write timeout, command = %d\n", command);
 199                         goto end;
 200                 }
 201         } else if (command == ACPI_EC_COMMAND_QUERY) {
 202                 atomic_set(&ec->query_pending, 0);
 203         }
 204
 205         for (; rdata_len > 0; --rdata_len) {
 206                 result = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF_1, count);
 207                 if (result) {
 208                         printk(KERN_ERR PREFIX "read timeout, command = %d\n",
 209                                command);
 210                         goto end;
 211                 }
 212                 count = atomic_read(&ec->event_count);
 213                 *(rdata++) = acpi_ec_read_data(ec);
 214         }
 215       end:
 216         return result;
 217 }
 218
 219 static int acpi_ec_transaction(struct acpi_ec *ec, u8 command,
 220                                const u8 * wdata, unsigned wdata_len,
 221                                u8 * rdata, unsigned rdata_len)
 222 {
 223         int status;
 224         u32 glk;
 225
 226         if (!ec || (wdata_len && !wdata) || (rdata_len && !rdata))
 227                 return -EINVAL;
 228
 229         if (rdata)
 230                 memset(rdata, 0, rdata_len);
 231
 232         mutex_lock(&ec->lock);
 233         if (ec->global_lock) {
 234                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 235                 if (ACPI_FAILURE(status)) {
 236                         mutex_unlock(&ec->lock);
 237                         return -ENODEV;
 238                 }
 239         }
 240
 241         /* Make sure GPE is enabled before doing transaction */
 242         acpi_enable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
 243
 244         status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0, 0);
 245         if (status) {
 246                 printk(KERN_DEBUG PREFIX
 247                        "input buffer is not empty, aborting transaction\n");
 248                 goto end;
 249         }
 250
 251         status = acpi_ec_transaction_unlocked(ec, command,
 252                                               wdata, wdata_len,
 253                                               rdata, rdata_len);
 254
 255       end:
 256
 257         if (ec->global_lock)
 258                 acpi_release_global_lock(glk);
 259         mutex_unlock(&ec->lock);
 260
 261         return status;
 262 }
 263
 264 /*
 265  * Note: samsung nv5000 doesn't work with ec burst mode.
 266  * http://bugzilla.kernel.org/show_bug.cgi?id=4980
 267  */
 268 int acpi_ec_burst_enable(struct acpi_ec *ec)
 269 {
 270         u8 d;
 271         return acpi_ec_transaction(ec, ACPI_EC_BURST_ENABLE, NULL, 0, &d, 1);
 272 }
 273
 274 int acpi_ec_burst_disable(struct acpi_ec *ec)
 275 {
 276         return acpi_ec_transaction(ec, ACPI_EC_BURST_DISABLE, NULL, 0, NULL, 0);
 277 }
 278
 279 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 * data)
 280 {
 281         int result;
 282         u8 d;
 283
 284         result = acpi_ec_transaction(ec, ACPI_EC_COMMAND_READ,
 285                                      &address, 1, &d, 1);
 286         *data = d;
 287         return result;
 288 }
 289
 290 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
 291 {
 292         u8 wdata[2] = { address, data };
 293         return acpi_ec_transaction(ec, ACPI_EC_COMMAND_WRITE,
 294                                    wdata, 2, NULL, 0);
 295 }
 296
 297 /*
 298  * Externally callable EC access functions. For now, assume 1 EC only
 299  */
 300 int ec_burst_enable(void)
 301 {
 302         struct acpi_ec *ec;
 303         if (!first_ec)
 304                 return -ENODEV;
 305         ec = acpi_driver_data(first_ec);
 306         return acpi_ec_burst_enable(ec);
 307 }
 308
 309 EXPORT_SYMBOL(ec_burst_enable);
 310
 311 int ec_burst_disable(void)
 312 {
 313         struct acpi_ec *ec;
 314         if (!first_ec)
 315                 return -ENODEV;
 316         ec = acpi_driver_data(first_ec);
 317         return acpi_ec_burst_disable(ec);
 318 }
 319
 320 EXPORT_SYMBOL(ec_burst_disable);
 321
 322 int ec_read(u8 addr, u8 * val)
 323 {
 324         struct acpi_ec *ec;
 325         int err;
 326         u8 temp_data;
 327
 328         if (!first_ec)
 329                 return -ENODEV;
 330
 331         ec = acpi_driver_data(first_ec);
 332
 333         err = acpi_ec_read(ec, addr, &temp_data);
 334
 335         if (!err) {
 336                 *val = temp_data;
 337                 return 0;
 338         } else
 339                 return err;
 340 }
 341
 342 EXPORT_SYMBOL(ec_read);
 343
 344 int ec_write(u8 addr, u8 val)
 345 {
 346         struct acpi_ec *ec;
 347         int err;
 348
 349         if (!first_ec)
 350                 return -ENODEV;
 351
 352         ec = acpi_driver_data(first_ec);
 353
 354         err = acpi_ec_write(ec, addr, val);
 355
 356         return err;
 357 }
 358
 359 EXPORT_SYMBOL(ec_write);
 360
 361 int ec_transaction(u8 command,
 362                    const u8 * wdata, unsigned wdata_len,
 363                    u8 * rdata, unsigned rdata_len)
 364 {
 365         struct acpi_ec *ec;
 366
 367         if (!first_ec)
 368                 return -ENODEV;
 369
 370         ec = acpi_driver_data(first_ec);
 371
 372         return acpi_ec_transaction(ec, command, wdata,
 373                                    wdata_len, rdata, rdata_len);
 374 }
 375
 376 EXPORT_SYMBOL(ec_transaction);
 377
 378 static int acpi_ec_query(struct acpi_ec *ec, u8 * data)
 379 {
 380         int result;
 381         u8 d;
 382
 383         if (!ec || !data)
 384                 return -EINVAL;
 385
 386         /*
 387          * Query the EC to find out which _Qxx method we need to evaluate.
 388          * Note that successful completion of the query causes the ACPI_EC_SCI
 389          * bit to be cleared (and thus clearing the interrupt source).
 390          */
 391
 392         result = acpi_ec_transaction(ec, ACPI_EC_COMMAND_QUERY, NULL, 0, &d, 1);
 393         if (result)
 394                 return result;
 395
 396         if (!d)
 397                 return -ENODATA;
 398
 399         *data = d;
 400         return 0;
 401 }
 402
 403 /* --------------------------------------------------------------------------
 404                                 Event Management
 405    -------------------------------------------------------------------------- */
 406
 407 static void acpi_ec_gpe_query(void *ec_cxt)
 408 {
 409         struct acpi_ec *ec = (struct acpi_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 = (struct acpi_ec *)data;
 428         atomic_inc(&ec->event_count);
 429         if (acpi_ec_mode == EC_INTR) {
 430                 wake_up(&ec->wait);
 431         }
 432
 433         value = acpi_ec_read_status(ec);
 434         if ((value & ACPI_EC_FLAG_SCI) && !atomic_read(&ec->query_pending)) {
 435                 atomic_set(&ec->query_pending, 1);
 436                 status =
 437                     acpi_os_execute(OSL_EC_BURST_HANDLER, acpi_ec_gpe_query,
 438                                     ec);
 439         }
 440
 441         return status == AE_OK ?
 442             ACPI_INTERRUPT_HANDLED : ACPI_INTERRUPT_NOT_HANDLED;
 443 }
 444
 445 /* --------------------------------------------------------------------------
 446                              Address Space Management
 447    -------------------------------------------------------------------------- */
 448
 449 static acpi_status
 450 acpi_ec_space_setup(acpi_handle region_handle,
 451                     u32 function, void *handler_context, void **return_context)
 452 {
 453         /*
 454          * The EC object is in the handler context and is needed
 455          * when calling the acpi_ec_space_handler.
 456          */
 457         *return_context = (function != ACPI_REGION_DEACTIVATE) ?
 458             handler_context : NULL;
 459
 460         return AE_OK;
 461 }
 462
 463 static acpi_status
 464 acpi_ec_space_handler(u32 function,
 465                       acpi_physical_address address,
 466                       u32 bit_width,
 467                       acpi_integer * value,
 468                       void *handler_context, void *region_context)
 469 {
 470         int result = 0;
 471         struct acpi_ec *ec = NULL;
 472         u64 temp = *value;
 473         acpi_integer f_v = 0;
 474         int i = 0;
 475
 476         if ((address > 0xFF) || !value || !handler_context)
 477                 return AE_BAD_PARAMETER;
 478
 479         if (bit_width != 8 && acpi_strict) {
 480                 return AE_BAD_PARAMETER;
 481         }
 482
 483         ec = (struct acpi_ec *)handler_context;
 484
 485       next_byte:
 486         switch (function) {
 487         case ACPI_READ:
 488                 temp = 0;
 489                 result = acpi_ec_read(ec, (u8) address, (u8 *) & temp);
 490                 break;
 491         case ACPI_WRITE:
 492                 result = acpi_ec_write(ec, (u8) address, (u8) temp);
 493                 break;
 494         default:
 495                 result = -EINVAL;
 496                 goto out;
 497                 break;
 498         }
 499
 500         bit_width -= 8;
 501         if (bit_width) {
 502                 if (function == ACPI_READ)
 503                         f_v |= temp << 8 * i;
 504                 if (function == ACPI_WRITE)
 505                         temp >>= 8;
 506                 i++;
 507                 address++;
 508                 goto next_byte;
 509         }
 510
 511         if (function == ACPI_READ) {
 512                 f_v |= temp << 8 * i;
 513                 *value = f_v;
 514         }
 515
 516       out:
 517         switch (result) {
 518         case -EINVAL:
 519                 return AE_BAD_PARAMETER;
 520                 break;
 521         case -ENODEV:
 522                 return AE_NOT_FOUND;
 523                 break;
 524         case -ETIME:
 525                 return AE_TIME;
 526                 break;
 527         default:
 528                 return AE_OK;
 529         }
 530 }
 531
 532 /* --------------------------------------------------------------------------
 533                               FS Interface (/proc)
 534    -------------------------------------------------------------------------- */
 535
 536 static struct proc_dir_entry *acpi_ec_dir;
 537
 538 static int acpi_ec_read_info(struct seq_file *seq, void *offset)
 539 {
 540         struct acpi_ec *ec = (struct acpi_ec *)seq->private;
 541
 542         if (!ec)
 543                 goto end;
 544
 545         seq_printf(seq, "gpe:                 0x%02x\n", (u32) ec->gpe);
 546         seq_printf(seq, "ports:                   0x%02x, 0x%02x\n",
 547                    (u32) ec->command_addr, (u32) ec->data_addr);
 548         seq_printf(seq, "use global lock:         %s\n",
 549                    ec->global_lock ? "yes" : "no");
 550         acpi_enable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
 551
 552       end:
 553         return 0;
 554 }
 555
 556 static int acpi_ec_info_open_fs(struct inode *inode, struct file *file)
 557 {
 558         return single_open(file, acpi_ec_read_info, PDE(inode)->data);
 559 }
 560
 561 static struct file_operations acpi_ec_info_ops = {
 562         .open = acpi_ec_info_open_fs,
 563         .read = seq_read,
 564         .llseek = seq_lseek,
 565         .release = single_release,
 566         .owner = THIS_MODULE,
 567 };
 568
 569 static int acpi_ec_add_fs(struct acpi_device *device)
 570 {
 571         struct proc_dir_entry *entry = NULL;
 572
 573         if (!acpi_device_dir(device)) {
 574                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
 575                                                      acpi_ec_dir);
 576                 if (!acpi_device_dir(device))
 577                         return -ENODEV;
 578         }
 579
 580         entry = create_proc_entry(ACPI_EC_FILE_INFO, S_IRUGO,
 581                                   acpi_device_dir(device));
 582         if (!entry)
 583                 return -ENODEV;
 584         else {
 585                 entry->proc_fops = &acpi_ec_info_ops;
 586                 entry->data = acpi_driver_data(device);
 587                 entry->owner = THIS_MODULE;
 588         }
 589
 590         return 0;
 591 }
 592
 593 static int acpi_ec_remove_fs(struct acpi_device *device)
 594 {
 595
 596         if (acpi_device_dir(device)) {
 597                 remove_proc_entry(ACPI_EC_FILE_INFO, acpi_device_dir(device));
 598                 remove_proc_entry(acpi_device_bid(device), acpi_ec_dir);
 599                 acpi_device_dir(device) = NULL;
 600         }
 601
 602         return 0;
 603 }
 604
 605 /* --------------------------------------------------------------------------
 606                                Driver Interface
 607    -------------------------------------------------------------------------- */
 608
 609 static int acpi_ec_add(struct acpi_device *device)
 610 {
 611         int result = 0;
 612         acpi_status status = AE_OK;
 613         struct acpi_ec *ec = NULL;
 614
 615         if (!device)
 616                 return -EINVAL;
 617
 618         ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
 619         if (!ec)
 620                 return -ENOMEM;
 621
 622         ec->handle = device->handle;
 623         ec->uid = -1;
 624         mutex_init(&ec->lock);
 625         atomic_set(&ec->query_pending, 0);
 626         atomic_set(&ec->event_count, 1);
 627         if (acpi_ec_mode == EC_INTR) {
 628                 init_waitqueue_head(&ec->wait);
 629         }
 630         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
 631         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
 632         acpi_driver_data(device) = ec;
 633
 634         /* Use the global lock for all EC transactions? */
 635         acpi_evaluate_integer(ec->handle, "_GLK", NULL, &ec->global_lock);
 636
 637         /* XXX we don't test uids, because on some boxes ecdt uid = 0, see:
 638            http://bugzilla.kernel.org/show_bug.cgi?id=6111 */
 639         if (ec_ecdt) {
 640                 acpi_remove_address_space_handler(ACPI_ROOT_OBJECT,
 641                                                   ACPI_ADR_SPACE_EC,
 642                                                   &acpi_ec_space_handler);
 643
 644                 acpi_remove_gpe_handler(NULL, ec_ecdt->gpe,
 645                                         &acpi_ec_gpe_handler);
 646
 647                 kfree(ec_ecdt);
 648         }
 649
 650         /* Get GPE bit assignment (EC events). */
 651         /* TODO: Add support for _GPE returning a package */
 652         status = acpi_evaluate_integer(ec->handle, "_GPE", NULL, &ec->gpe);
 653         if (ACPI_FAILURE(status)) {
 654                 ACPI_EXCEPTION((AE_INFO, status,
 655                                 "Obtaining GPE bit assignment"));
 656                 result = -ENODEV;
 657                 goto end;
 658         }
 659
 660         result = acpi_ec_add_fs(device);
 661         if (result)
 662                 goto end;
 663
 664         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "%s [%s] (gpe %d) interrupt mode.",
 665                           acpi_device_name(device), acpi_device_bid(device),
 666                           (u32) ec->gpe));
 667
 668         if (!first_ec)
 669                 first_ec = device;
 670
 671       end:
 672         if (result)
 673                 kfree(ec);
 674
 675         return result;
 676 }
 677
 678 static int acpi_ec_remove(struct acpi_device *device, int type)
 679 {
 680         struct acpi_ec *ec = NULL;
 681
 682         if (!device)
 683                 return -EINVAL;
 684
 685         ec = acpi_driver_data(device);
 686
 687         acpi_ec_remove_fs(device);
 688
 689         kfree(ec);
 690
 691         return 0;
 692 }
 693
 694 static acpi_status
 695 acpi_ec_io_ports(struct acpi_resource *resource, void *context)
 696 {
 697         struct acpi_ec *ec = (struct acpi_ec *)context;
 698
 699         if (resource->type != ACPI_RESOURCE_TYPE_IO) {
 700                 return AE_OK;
 701         }
 702
 703         /*
 704          * The first address region returned is the data port, and
 705          * the second address region returned is the status/command
 706          * port.
 707          */
 708         if (ec->data_addr == 0) {
 709                 ec->data_addr = resource->data.io.minimum;
 710         } else if (ec->command_addr == 0) {
 711                 ec->command_addr = resource->data.io.minimum;
 712         } else {
 713                 return AE_CTRL_TERMINATE;
 714         }
 715
 716         return AE_OK;
 717 }
 718
 719 static int acpi_ec_start(struct acpi_device *device)
 720 {
 721         acpi_status status = AE_OK;
 722         struct acpi_ec *ec = NULL;
 723
 724         if (!device)
 725                 return -EINVAL;
 726
 727         ec = acpi_driver_data(device);
 728
 729         if (!ec)
 730                 return -EINVAL;
 731
 732         /*
 733          * Get I/O port addresses. Convert to GAS format.
 734          */
 735         status = acpi_walk_resources(ec->handle, METHOD_NAME__CRS,
 736                                      acpi_ec_io_ports, ec);
 737         if (ACPI_FAILURE(status) || ec->command_addr == 0) {
 738                 ACPI_EXCEPTION((AE_INFO, status,
 739                                 "Error getting I/O port addresses"));
 740                 return -ENODEV;
 741         }
 742
 743         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "gpe=0x%02lx, ports=0x%2lx,0x%2lx",
 744                           ec->gpe, ec->command_addr, ec->data_addr));
 745
 746         /*
 747          * Install GPE handler
 748          */
 749         status = acpi_install_gpe_handler(NULL, ec->gpe,
 750                                           ACPI_GPE_EDGE_TRIGGERED,
 751                                           &acpi_ec_gpe_handler, ec);
 752         if (ACPI_FAILURE(status)) {
 753                 return -ENODEV;
 754         }
 755         acpi_set_gpe_type(NULL, ec->gpe, ACPI_GPE_TYPE_RUNTIME);
 756         acpi_enable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
 757
 758         status = acpi_install_address_space_handler(ec->handle,
 759                                                     ACPI_ADR_SPACE_EC,
 760                                                     &acpi_ec_space_handler,
 761                                                     &acpi_ec_space_setup, ec);
 762         if (ACPI_FAILURE(status)) {
 763                 acpi_remove_gpe_handler(NULL, ec->gpe, &acpi_ec_gpe_handler);
 764                 return -ENODEV;
 765         }
 766
 767         return AE_OK;
 768 }
 769
 770 static int acpi_ec_stop(struct acpi_device *device, int type)
 771 {
 772         acpi_status status = AE_OK;
 773         struct acpi_ec *ec = NULL;
 774
 775         if (!device)
 776                 return -EINVAL;
 777
 778         ec = acpi_driver_data(device);
 779
 780         status = acpi_remove_address_space_handler(ec->handle,
 781                                                    ACPI_ADR_SPACE_EC,
 782                                                    &acpi_ec_space_handler);
 783         if (ACPI_FAILURE(status))
 784                 return -ENODEV;
 785
 786         status = acpi_remove_gpe_handler(NULL, ec->gpe, &acpi_ec_gpe_handler);
 787         if (ACPI_FAILURE(status))
 788                 return -ENODEV;
 789
 790         return 0;
 791 }
 792
 793 static int __init acpi_ec_get_real_ecdt(void)
 794 {
 795         acpi_status status;
 796         struct acpi_table_ecdt *ecdt_ptr;
 797
 798         status = acpi_get_table(ACPI_SIG_ECDT, 1,
 799                                 (struct acpi_table_header **)&ecdt_ptr);
 800         if (ACPI_FAILURE(status))
 801                 return -ENODEV;
 802
 803         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found ECDT"));
 804
 805         /*
 806          * Generate a temporary ec context to use until the namespace is scanned
 807          */
 808         ec_ecdt = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
 809         if (!ec_ecdt)
 810                 return -ENOMEM;
 811
 812         mutex_init(&ec_ecdt->lock);
 813         atomic_set(&ec_ecdt->event_count, 1);
 814         if (acpi_ec_mode == EC_INTR) {
 815                 init_waitqueue_head(&ec_ecdt->wait);
 816         }
 817         ec_ecdt->command_addr = ecdt_ptr->control.address;
 818         ec_ecdt->data_addr = ecdt_ptr->data.address;
 819         ec_ecdt->gpe = ecdt_ptr->gpe;
 820         ec_ecdt->uid = ecdt_ptr->uid;
 821
 822         status = acpi_get_handle(NULL, ecdt_ptr->id, &ec_ecdt->handle);
 823         if (ACPI_FAILURE(status)) {
 824                 goto error;
 825         }
 826
 827         return 0;
 828       error:
 829         ACPI_EXCEPTION((AE_INFO, status, "Could not use ECDT"));
 830         kfree(ec_ecdt);
 831         ec_ecdt = NULL;
 832
 833         return -ENODEV;
 834 }
 835
 836 int __init acpi_ec_ecdt_probe(void)
 837 {
 838         acpi_status status;
 839         int ret;
 840
 841         ret = acpi_ec_get_real_ecdt();
 842         if (ret)
 843                 return 0;
 844
 845         /*
 846          * Install GPE handler
 847          */
 848         status = acpi_install_gpe_handler(NULL, ec_ecdt->gpe,
 849                                           ACPI_GPE_EDGE_TRIGGERED,
 850                                           &acpi_ec_gpe_handler, ec_ecdt);
 851         if (ACPI_FAILURE(status)) {
 852                 goto error;
 853         }
 854         acpi_set_gpe_type(NULL, ec_ecdt->gpe, ACPI_GPE_TYPE_RUNTIME);
 855         acpi_enable_gpe(NULL, ec_ecdt->gpe, ACPI_NOT_ISR);
 856
 857         status = acpi_install_address_space_handler(ACPI_ROOT_OBJECT,
 858                                                     ACPI_ADR_SPACE_EC,
 859                                                     &acpi_ec_space_handler,
 860                                                     &acpi_ec_space_setup,
 861                                                     ec_ecdt);
 862         if (ACPI_FAILURE(status)) {
 863                 acpi_remove_gpe_handler(NULL, ec_ecdt->gpe,
 864                                         &acpi_ec_gpe_handler);
 865                 goto error;
 866         }
 867
 868         return 0;
 869
 870       error:
 871         ACPI_EXCEPTION((AE_INFO, status, "Could not use ECDT"));
 872         kfree(ec_ecdt);
 873         ec_ecdt = NULL;
 874
 875         return -ENODEV;
 876 }
 877
 878 static int __init acpi_ec_init(void)
 879 {
 880         int result = 0;
 881
 882         if (acpi_disabled)
 883                 return 0;
 884
 885         acpi_ec_dir = proc_mkdir(ACPI_EC_CLASS, acpi_root_dir);
 886         if (!acpi_ec_dir)
 887                 return -ENODEV;
 888
 889         /* Now register the driver for the EC */
 890         result = acpi_bus_register_driver(&acpi_ec_driver);
 891         if (result < 0) {
 892                 remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
 893                 return -ENODEV;
 894         }
 895
 896         return result;
 897 }
 898
 899 subsys_initcall(acpi_ec_init);
 900
 901 /* EC driver currently not unloadable */
 902 #if 0
 903 static void __exit acpi_ec_exit(void)
 904 {
 905
 906         acpi_bus_unregister_driver(&acpi_ec_driver);
 907
 908         remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
 909
 910         return;
 911 }
 912 #endif                          /* 0 */
 913
 914 static int __init acpi_ec_set_intr_mode(char *str)
 915 {
 916         int intr;
 917
 918         if (!get_option(&str, &intr))
 919                 return 0;
 920
 921         if (intr) {
 922                 acpi_ec_mode = EC_INTR;
 923         } else {
 924                 acpi_ec_mode = EC_POLL;
 925         }
 926         acpi_ec_driver.ops.add = acpi_ec_add;
 927         printk(KERN_NOTICE PREFIX "%s mode.\n", intr ? "interrupt" : "polling");
 928
 929         return 1;
 930 }
 931
 932 __setup("ec_intr=", acpi_ec_set_intr_mode);