drivers/acpi/ec.c

   1 /*
   2  *  ec.c - ACPI Embedded Controller Driver (v2.0)
   3  *
   4  *  Copyright (C) 2006, 2007 Alexey Starikovskiy <alexey.y.starikovskiy@intel.com>
   5  *  Copyright (C) 2006 Denis Sadykov <denis.m.sadykov@intel.com>
   6  *  Copyright (C) 2004 Luming Yu <luming.yu@intel.com>
   7  *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
   8  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
   9  *
  10  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  11  *
  12  *  This program is free software; you can redistribute it and/or modify
  13  *  it under the terms of the GNU General Public License as published by
  14  *  the Free Software Foundation; either version 2 of the License, or (at
  15  *  your option) any later version.
  16  *
  17  *  This program is distributed in the hope that it will be useful, but
  18  *  WITHOUT ANY WARRANTY; without even the implied warranty of
  19  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  20  *  General Public License for more details.
  21  *
  22  *  You should have received a copy of the GNU General Public License along
  23  *  with this program; if not, write to the Free Software Foundation, Inc.,
  24  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
  25  *
  26  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  27  */
  28
  29 #include <linux/kernel.h>
  30 #include <linux/module.h>
  31 #include <linux/init.h>
  32 #include <linux/types.h>
  33 #include <linux/delay.h>
  34 #include <linux/proc_fs.h>
  35 #include <linux/seq_file.h>
  36 #include <linux/interrupt.h>
  37 #include <linux/list.h>
  38 #include <asm/io.h>
  39 #include <acpi/acpi_bus.h>
  40 #include <acpi/acpi_drivers.h>
  41 #include <acpi/actypes.h>
  42
  43 #define ACPI_EC_CLASS                   "embedded_controller"
  44 #define ACPI_EC_DEVICE_NAME             "Embedded Controller"
  45 #define ACPI_EC_FILE_INFO               "info"
  46
  47 #undef PREFIX
  48 #define PREFIX                          "ACPI: EC: "
  49
  50 /* EC status register */
  51 #define ACPI_EC_FLAG_OBF        0x01    /* Output buffer full */
  52 #define ACPI_EC_FLAG_IBF        0x02    /* Input buffer full */
  53 #define ACPI_EC_FLAG_BURST      0x10    /* burst mode */
  54 #define ACPI_EC_FLAG_SCI        0x20    /* EC-SCI occurred */
  55
  56 /* EC commands */
  57 enum ec_command {
  58         ACPI_EC_COMMAND_READ = 0x80,
  59         ACPI_EC_COMMAND_WRITE = 0x81,
  60         ACPI_EC_BURST_ENABLE = 0x82,
  61         ACPI_EC_BURST_DISABLE = 0x83,
  62         ACPI_EC_COMMAND_QUERY = 0x84,
  63 };
  64
  65 /* EC events */
  66 enum ec_event {
  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 static enum ec_mode {
  75         EC_INTR = 1,            /* Output buffer full */
  76         EC_POLL,                /* Input buffer empty */
  77 } acpi_ec_mode = EC_INTR;
  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 const struct acpi_device_id ec_device_ids[] = {
  85         {"PNP0C09", 0},
  86         {"", 0},
  87 };
  88
  89 static struct acpi_driver acpi_ec_driver = {
  90         .name = "ec",
  91         .class = ACPI_EC_CLASS,
  92         .ids = ec_device_ids,
  93         .ops = {
  94                 .add = acpi_ec_add,
  95                 .remove = acpi_ec_remove,
  96                 .start = acpi_ec_start,
  97                 .stop = acpi_ec_stop,
  98                 },
  99 };
 100
 101 /* If we find an EC via the ECDT, we need to keep a ptr to its context */
 102 /* External interfaces use first EC only, so remember */
 103 typedef int (*acpi_ec_query_func) (void *data);
 104
 105 struct acpi_ec_query_handler {
 106         struct list_head node;
 107         acpi_ec_query_func func;
 108         acpi_handle handle;
 109         void *data;
 110         u8 query_bit;
 111 };
 112
 113 static struct acpi_ec {
 114         acpi_handle handle;
 115         unsigned long gpe;
 116         unsigned long command_addr;
 117         unsigned long data_addr;
 118         unsigned long global_lock;
 119         struct mutex lock;
 120         atomic_t query_pending;
 121         atomic_t event_count;
 122         wait_queue_head_t wait;
 123         struct list_head list;
 124 } *boot_ec, *first_ec;
 125
 126 /* --------------------------------------------------------------------------
 127                              Transaction Management
 128    -------------------------------------------------------------------------- */
 129
 130 static inline u8 acpi_ec_read_status(struct acpi_ec *ec)
 131 {
 132         return inb(ec->command_addr);
 133 }
 134
 135 static inline u8 acpi_ec_read_data(struct acpi_ec *ec)
 136 {
 137         return inb(ec->data_addr);
 138 }
 139
 140 static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command)
 141 {
 142         outb(command, ec->command_addr);
 143 }
 144
 145 static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data)
 146 {
 147         outb(data, ec->data_addr);
 148 }
 149
 150 static inline int acpi_ec_check_status(struct acpi_ec *ec, enum ec_event event,
 151                                        unsigned old_count)
 152 {
 153         u8 status = acpi_ec_read_status(ec);
 154         if (old_count == atomic_read(&ec->event_count))
 155                 return 0;
 156         if (event == ACPI_EC_EVENT_OBF_1) {
 157                 if (status & ACPI_EC_FLAG_OBF)
 158                         return 1;
 159         } else if (event == ACPI_EC_EVENT_IBF_0) {
 160                 if (!(status & ACPI_EC_FLAG_IBF))
 161                         return 1;
 162         }
 163
 164         return 0;
 165 }
 166
 167 static int acpi_ec_wait(struct acpi_ec *ec, enum ec_event event,
 168                         unsigned count, int force_poll)
 169 {
 170         if (unlikely(force_poll) || acpi_ec_mode == EC_POLL) {
 171                 unsigned long delay = jiffies + msecs_to_jiffies(ACPI_EC_DELAY);
 172                 while (time_before(jiffies, delay)) {
 173                         if (acpi_ec_check_status(ec, event, 0))
 174                                 return 0;
 175                 }
 176         } else {
 177                 if (wait_event_timeout(ec->wait,
 178                                        acpi_ec_check_status(ec, event, count),
 179                                        msecs_to_jiffies(ACPI_EC_DELAY)) ||
 180                     acpi_ec_check_status(ec, event, 0)) {
 181                         return 0;
 182                 } else {
 183                         printk(KERN_ERR PREFIX "acpi_ec_wait timeout,"
 184                                " status = %d, expect_event = %d\n",
 185                                acpi_ec_read_status(ec), event);
 186                 }
 187         }
 188
 189         return -ETIME;
 190 }
 191
 192 static int acpi_ec_transaction_unlocked(struct acpi_ec *ec, u8 command,
 193                                         const u8 * wdata, unsigned wdata_len,
 194                                         u8 * rdata, unsigned rdata_len,
 195                                         int force_poll)
 196 {
 197         int result = 0;
 198         unsigned count = atomic_read(&ec->event_count);
 199         acpi_ec_write_cmd(ec, command);
 200
 201         for (; wdata_len > 0; --wdata_len) {
 202                 result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0, count, force_poll);
 203                 if (result) {
 204                         printk(KERN_ERR PREFIX
 205                                "write_cmd timeout, command = %d\n", command);
 206                         goto end;
 207                 }
 208                 count = atomic_read(&ec->event_count);
 209                 acpi_ec_write_data(ec, *(wdata++));
 210         }
 211
 212         if (!rdata_len) {
 213                 result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0, count, force_poll);
 214                 if (result) {
 215                         printk(KERN_ERR PREFIX
 216                                "finish-write timeout, command = %d\n", command);
 217                         goto end;
 218                 }
 219         } else if (command == ACPI_EC_COMMAND_QUERY) {
 220                 atomic_set(&ec->query_pending, 0);
 221         }
 222
 223         for (; rdata_len > 0; --rdata_len) {
 224                 result = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF_1, count, force_poll);
 225                 if (result) {
 226                         printk(KERN_ERR PREFIX "read timeout, command = %d\n",
 227                                command);
 228                         goto end;
 229                 }
 230                 count = atomic_read(&ec->event_count);
 231                 *(rdata++) = acpi_ec_read_data(ec);
 232         }
 233       end:
 234         return result;
 235 }
 236
 237 static int acpi_ec_transaction(struct acpi_ec *ec, u8 command,
 238                                const u8 * wdata, unsigned wdata_len,
 239                                u8 * rdata, unsigned rdata_len,
 240                                int force_poll)
 241 {
 242         int status;
 243         u32 glk;
 244
 245         if (!ec || (wdata_len && !wdata) || (rdata_len && !rdata))
 246                 return -EINVAL;
 247
 248         if (rdata)
 249                 memset(rdata, 0, rdata_len);
 250
 251         mutex_lock(&ec->lock);
 252         if (ec->global_lock) {
 253                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 254                 if (ACPI_FAILURE(status)) {
 255                         mutex_unlock(&ec->lock);
 256                         return -ENODEV;
 257                 }
 258         }
 259
 260         /* Make sure GPE is enabled before doing transaction */
 261         acpi_enable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
 262
 263         status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0, 0, 0);
 264         if (status) {
 265                 printk(KERN_ERR PREFIX
 266                        "input buffer is not empty, aborting transaction\n");
 267                 goto end;
 268         }
 269
 270         status = acpi_ec_transaction_unlocked(ec, command,
 271                                               wdata, wdata_len,
 272                                               rdata, rdata_len,
 273                                               force_poll);
 274
 275       end:
 276
 277         if (ec->global_lock)
 278                 acpi_release_global_lock(glk);
 279         mutex_unlock(&ec->lock);
 280
 281         return status;
 282 }
 283
 284 /*
 285  * Note: samsung nv5000 doesn't work with ec burst mode.
 286  * http://bugzilla.kernel.org/show_bug.cgi?id=4980
 287  */
 288 int acpi_ec_burst_enable(struct acpi_ec *ec)
 289 {
 290         u8 d;
 291         return acpi_ec_transaction(ec, ACPI_EC_BURST_ENABLE, NULL, 0, &d, 1, 0);
 292 }
 293
 294 int acpi_ec_burst_disable(struct acpi_ec *ec)
 295 {
 296         return acpi_ec_transaction(ec, ACPI_EC_BURST_DISABLE, NULL, 0, NULL, 0, 0);
 297 }
 298
 299 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 * data)
 300 {
 301         int result;
 302         u8 d;
 303
 304         result = acpi_ec_transaction(ec, ACPI_EC_COMMAND_READ,
 305                                      &address, 1, &d, 1, 0);
 306         *data = d;
 307         return result;
 308 }
 309
 310 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
 311 {
 312         u8 wdata[2] = { address, data };
 313         return acpi_ec_transaction(ec, ACPI_EC_COMMAND_WRITE,
 314                                    wdata, 2, NULL, 0, 0);
 315 }
 316
 317 /*
 318  * Externally callable EC access functions. For now, assume 1 EC only
 319  */
 320 int ec_burst_enable(void)
 321 {
 322         if (!first_ec)
 323                 return -ENODEV;
 324         return acpi_ec_burst_enable(first_ec);
 325 }
 326
 327 EXPORT_SYMBOL(ec_burst_enable);
 328
 329 int ec_burst_disable(void)
 330 {
 331         if (!first_ec)
 332                 return -ENODEV;
 333         return acpi_ec_burst_disable(first_ec);
 334 }
 335
 336 EXPORT_SYMBOL(ec_burst_disable);
 337
 338 int ec_read(u8 addr, u8 * val)
 339 {
 340         int err;
 341         u8 temp_data;
 342
 343         if (!first_ec)
 344                 return -ENODEV;
 345
 346         err = acpi_ec_read(first_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         int err;
 360
 361         if (!first_ec)
 362                 return -ENODEV;
 363
 364         err = acpi_ec_write(first_ec, addr, val);
 365
 366         return err;
 367 }
 368
 369 EXPORT_SYMBOL(ec_write);
 370
 371 int ec_transaction(u8 command,
 372                    const u8 * wdata, unsigned wdata_len,
 373                    u8 * rdata, unsigned rdata_len,
 374                    int force_poll)
 375 {
 376         if (!first_ec)
 377                 return -ENODEV;
 378
 379         return acpi_ec_transaction(first_ec, command, wdata,
 380                                    wdata_len, rdata, rdata_len,
 381                                    force_poll);
 382 }
 383
 384 EXPORT_SYMBOL(ec_transaction);
 385
 386 static int acpi_ec_query(struct acpi_ec *ec, u8 * data)
 387 {
 388         int result;
 389         u8 d;
 390
 391         if (!ec || !data)
 392                 return -EINVAL;
 393
 394         /*
 395          * Query the EC to find out which _Qxx method we need to evaluate.
 396          * Note that successful completion of the query causes the ACPI_EC_SCI
 397          * bit to be cleared (and thus clearing the interrupt source).
 398          */
 399
 400         result = acpi_ec_transaction(ec, ACPI_EC_COMMAND_QUERY, NULL, 0, &d, 1, 0);
 401         if (result)
 402                 return result;
 403
 404         if (!d)
 405                 return -ENODATA;
 406
 407         *data = d;
 408         return 0;
 409 }
 410
 411 /* --------------------------------------------------------------------------
 412                                 Event Management
 413    -------------------------------------------------------------------------- */
 414 int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
 415                               acpi_handle handle, acpi_ec_query_func func,
 416                               void *data)
 417 {
 418         struct acpi_ec_query_handler *handler =
 419             kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL);
 420         if (!handler)
 421                 return -ENOMEM;
 422
 423         handler->query_bit = query_bit;
 424         handler->handle = handle;
 425         handler->func = func;
 426         handler->data = data;
 427         mutex_lock(&ec->lock);
 428         list_add(&handler->node, &ec->list);
 429         mutex_unlock(&ec->lock);
 430         return 0;
 431 }
 432
 433 EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler);
 434
 435 void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit)
 436 {
 437         struct acpi_ec_query_handler *handler;
 438         mutex_lock(&ec->lock);
 439         list_for_each_entry(handler, &ec->list, node) {
 440                 if (query_bit == handler->query_bit) {
 441                         list_del(&handler->node);
 442                         kfree(handler);
 443                 }
 444         }
 445         mutex_unlock(&ec->lock);
 446 }
 447
 448 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler);
 449
 450 static void acpi_ec_gpe_query(void *ec_cxt)
 451 {
 452         struct acpi_ec *ec = ec_cxt;
 453         u8 value = 0;
 454         struct acpi_ec_query_handler *handler, copy;
 455
 456         if (!ec || acpi_ec_query(ec, &value))
 457                 return;
 458         mutex_lock(&ec->lock);
 459         list_for_each_entry(handler, &ec->list, node) {
 460                 if (value == handler->query_bit) {
 461                         /* have custom handler for this bit */
 462                         memcpy(&copy, handler, sizeof(copy));
 463                         mutex_unlock(&ec->lock);
 464                         if (copy.func) {
 465                                 copy.func(copy.data);
 466                         } else if (copy.handle) {
 467                                 acpi_evaluate_object(copy.handle, NULL, NULL, NULL);
 468                         }
 469                         return;
 470                 }
 471         }
 472         mutex_unlock(&ec->lock);
 473 }
 474
 475 static u32 acpi_ec_gpe_handler(void *data)
 476 {
 477         acpi_status status = AE_OK;
 478         u8 value;
 479         struct acpi_ec *ec = data;
 480
 481         atomic_inc(&ec->event_count);
 482
 483         if (acpi_ec_mode == EC_INTR) {
 484                 wake_up(&ec->wait);
 485         }
 486
 487         value = acpi_ec_read_status(ec);
 488         if ((value & ACPI_EC_FLAG_SCI) && !atomic_read(&ec->query_pending)) {
 489                 atomic_set(&ec->query_pending, 1);
 490                 status =
 491                     acpi_os_execute(OSL_EC_BURST_HANDLER, acpi_ec_gpe_query, ec);
 492         }
 493
 494         return status == AE_OK ?
 495             ACPI_INTERRUPT_HANDLED : ACPI_INTERRUPT_NOT_HANDLED;
 496 }
 497
 498 /* --------------------------------------------------------------------------
 499                              Address Space Management
 500    -------------------------------------------------------------------------- */
 501
 502 static acpi_status
 503 acpi_ec_space_setup(acpi_handle region_handle,
 504                     u32 function, void *handler_context, void **return_context)
 505 {
 506         /*
 507          * The EC object is in the handler context and is needed
 508          * when calling the acpi_ec_space_handler.
 509          */
 510         *return_context = (function != ACPI_REGION_DEACTIVATE) ?
 511             handler_context : NULL;
 512
 513         return AE_OK;
 514 }
 515
 516 static acpi_status
 517 acpi_ec_space_handler(u32 function, acpi_physical_address address,
 518                       u32 bits, acpi_integer *value,
 519                       void *handler_context, void *region_context)
 520 {
 521         struct acpi_ec *ec = handler_context;
 522         int result = 0, i = 0;
 523         u8 temp = 0;
 524
 525         if ((address > 0xFF) || !value || !handler_context)
 526                 return AE_BAD_PARAMETER;
 527
 528         if (function != ACPI_READ && function != ACPI_WRITE)
 529                 return AE_BAD_PARAMETER;
 530
 531         if (bits != 8 && acpi_strict)
 532                 return AE_BAD_PARAMETER;
 533
 534         while (bits - i > 0) {
 535                 if (function == ACPI_READ) {
 536                         result = acpi_ec_read(ec, address, &temp);
 537                         (*value) |= ((acpi_integer)temp) << i;
 538                 } else {
 539                         temp = 0xff & ((*value) >> i);
 540                         result = acpi_ec_write(ec, address, temp);
 541                 }
 542                 i += 8;
 543                 ++address;
 544         }
 545
 546         switch (result) {
 547         case -EINVAL:
 548                 return AE_BAD_PARAMETER;
 549                 break;
 550         case -ENODEV:
 551                 return AE_NOT_FOUND;
 552                 break;
 553         case -ETIME:
 554                 return AE_TIME;
 555                 break;
 556         default:
 557                 return AE_OK;
 558         }
 559 }
 560
 561 /* --------------------------------------------------------------------------
 562                               FS Interface (/proc)
 563    -------------------------------------------------------------------------- */
 564
 565 static struct proc_dir_entry *acpi_ec_dir;
 566
 567 static int acpi_ec_read_info(struct seq_file *seq, void *offset)
 568 {
 569         struct acpi_ec *ec = seq->private;
 570
 571         if (!ec)
 572                 goto end;
 573
 574         seq_printf(seq, "gpe:\t\t\t0x%02x\n", (u32) ec->gpe);
 575         seq_printf(seq, "ports:\t\t\t0x%02x, 0x%02x\n",
 576                    (unsigned)ec->command_addr, (unsigned)ec->data_addr);
 577         seq_printf(seq, "use global lock:\t%s\n",
 578                    ec->global_lock ? "yes" : "no");
 579       end:
 580         return 0;
 581 }
 582
 583 static int acpi_ec_info_open_fs(struct inode *inode, struct file *file)
 584 {
 585         return single_open(file, acpi_ec_read_info, PDE(inode)->data);
 586 }
 587
 588 static struct file_operations acpi_ec_info_ops = {
 589         .open = acpi_ec_info_open_fs,
 590         .read = seq_read,
 591         .llseek = seq_lseek,
 592         .release = single_release,
 593         .owner = THIS_MODULE,
 594 };
 595
 596 static int acpi_ec_add_fs(struct acpi_device *device)
 597 {
 598         struct proc_dir_entry *entry = NULL;
 599
 600         if (!acpi_device_dir(device)) {
 601                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
 602                                                      acpi_ec_dir);
 603                 if (!acpi_device_dir(device))
 604                         return -ENODEV;
 605         }
 606
 607         entry = create_proc_entry(ACPI_EC_FILE_INFO, S_IRUGO,
 608                                   acpi_device_dir(device));
 609         if (!entry)
 610                 return -ENODEV;
 611         else {
 612                 entry->proc_fops = &acpi_ec_info_ops;
 613                 entry->data = acpi_driver_data(device);
 614                 entry->owner = THIS_MODULE;
 615         }
 616
 617         return 0;
 618 }
 619
 620 static int acpi_ec_remove_fs(struct acpi_device *device)
 621 {
 622
 623         if (acpi_device_dir(device)) {
 624                 remove_proc_entry(ACPI_EC_FILE_INFO, acpi_device_dir(device));
 625                 remove_proc_entry(acpi_device_bid(device), acpi_ec_dir);
 626                 acpi_device_dir(device) = NULL;
 627         }
 628
 629         return 0;
 630 }
 631
 632 /* --------------------------------------------------------------------------
 633                                Driver Interface
 634    -------------------------------------------------------------------------- */
 635 static acpi_status
 636 ec_parse_io_ports(struct acpi_resource *resource, void *context);
 637
 638 static struct acpi_ec *make_acpi_ec(void)
 639 {
 640         struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
 641         if (!ec)
 642                 return NULL;
 643
 644         atomic_set(&ec->query_pending, 1);
 645         atomic_set(&ec->event_count, 1);
 646         mutex_init(&ec->lock);
 647         init_waitqueue_head(&ec->wait);
 648         INIT_LIST_HEAD(&ec->list);
 649
 650         return ec;
 651 }
 652
 653 static acpi_status
 654 acpi_ec_register_query_methods(acpi_handle handle, u32 level,
 655                                void *context, void **return_value)
 656 {
 657         struct acpi_namespace_node *node = handle;
 658         struct acpi_ec *ec = context;
 659         int value = 0;
 660         if (sscanf(node->name.ascii, "_Q%x", &value) == 1) {
 661                 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL);
 662         }
 663         return AE_OK;
 664 }
 665
 666 static acpi_status
 667 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
 668 {
 669         acpi_status status;
 670
 671         struct acpi_ec *ec = context;
 672         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
 673                                      ec_parse_io_ports, ec);
 674         if (ACPI_FAILURE(status))
 675                 return status;
 676
 677         /* Get GPE bit assignment (EC events). */
 678         /* TODO: Add support for _GPE returning a package */
 679         status = acpi_evaluate_integer(handle, "_GPE", NULL, &ec->gpe);
 680         if (ACPI_FAILURE(status))
 681                 return status;
 682
 683         /* Find and register all query methods */
 684         acpi_walk_namespace(ACPI_TYPE_METHOD, handle, 1,
 685                             acpi_ec_register_query_methods, ec, NULL);
 686
 687         /* Use the global lock for all EC transactions? */
 688         acpi_evaluate_integer(handle, "_GLK", NULL, &ec->global_lock);
 689
 690         ec->handle = handle;
 691
 692         printk(KERN_INFO PREFIX "GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n",
 693                           ec->gpe, ec->command_addr, ec->data_addr);
 694
 695         return AE_CTRL_TERMINATE;
 696 }
 697
 698 static int acpi_ec_add(struct acpi_device *device)
 699 {
 700         struct acpi_ec *ec = NULL;
 701
 702         if (!device)
 703                 return -EINVAL;
 704
 705         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
 706         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
 707
 708         ec = make_acpi_ec();
 709         if (!ec)
 710                 return -ENOMEM;
 711
 712         if (ec_parse_device(device->handle, 0, ec, NULL) !=
 713             AE_CTRL_TERMINATE) {
 714                 kfree(ec);
 715                 return -EINVAL;
 716         }
 717
 718         /* Check if we found the boot EC */
 719         if (boot_ec) {
 720                 if (boot_ec->gpe == ec->gpe) {
 721                         /* We might have incorrect info for GL at boot time */
 722                         mutex_lock(&boot_ec->lock);
 723                         boot_ec->global_lock = ec->global_lock;
 724                         /* Copy handlers from new ec into boot ec */
 725                         list_splice(&ec->list, &boot_ec->list);
 726                         mutex_unlock(&boot_ec->lock);
 727                         kfree(ec);
 728                         ec = boot_ec;
 729                 }
 730         } else
 731                 first_ec = ec;
 732         ec->handle = device->handle;
 733         acpi_driver_data(device) = ec;
 734
 735         acpi_ec_add_fs(device);
 736         return 0;
 737 }
 738
 739 static int acpi_ec_remove(struct acpi_device *device, int type)
 740 {
 741         struct acpi_ec *ec;
 742         struct acpi_ec_query_handler *handler, *tmp;
 743
 744         if (!device)
 745                 return -EINVAL;
 746
 747         ec = acpi_driver_data(device);
 748         mutex_lock(&ec->lock);
 749         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
 750                 list_del(&handler->node);
 751                 kfree(handler);
 752         }
 753         mutex_unlock(&ec->lock);
 754         acpi_ec_remove_fs(device);
 755         acpi_driver_data(device) = NULL;
 756         if (ec == first_ec)
 757                 first_ec = NULL;
 758
 759         /* Don't touch boot EC */
 760         if (boot_ec != ec)
 761                 kfree(ec);
 762         return 0;
 763 }
 764
 765 static acpi_status
 766 ec_parse_io_ports(struct acpi_resource *resource, void *context)
 767 {
 768         struct acpi_ec *ec = context;
 769
 770         if (resource->type != ACPI_RESOURCE_TYPE_IO)
 771                 return AE_OK;
 772
 773         /*
 774          * The first address region returned is the data port, and
 775          * the second address region returned is the status/command
 776          * port.
 777          */
 778         if (ec->data_addr == 0)
 779                 ec->data_addr = resource->data.io.minimum;
 780         else if (ec->command_addr == 0)
 781                 ec->command_addr = resource->data.io.minimum;
 782         else
 783                 return AE_CTRL_TERMINATE;
 784
 785         return AE_OK;
 786 }
 787
 788 static int ec_install_handlers(struct acpi_ec *ec)
 789 {
 790         acpi_status status;
 791         status = acpi_install_gpe_handler(NULL, ec->gpe,
 792                                           ACPI_GPE_EDGE_TRIGGERED,
 793                                           &acpi_ec_gpe_handler, ec);
 794         if (ACPI_FAILURE(status))
 795                 return -ENODEV;
 796
 797         acpi_set_gpe_type(NULL, ec->gpe, ACPI_GPE_TYPE_RUNTIME);
 798         acpi_enable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
 799
 800         status = acpi_install_address_space_handler(ec->handle,
 801                                                     ACPI_ADR_SPACE_EC,
 802                                                     &acpi_ec_space_handler,
 803                                                     &acpi_ec_space_setup, ec);
 804         if (ACPI_FAILURE(status)) {
 805                 acpi_remove_gpe_handler(NULL, ec->gpe, &acpi_ec_gpe_handler);
 806                 return -ENODEV;
 807         }
 808
 809         return 0;
 810 }
 811
 812 static int acpi_ec_start(struct acpi_device *device)
 813 {
 814         struct acpi_ec *ec;
 815         int ret = 0;
 816
 817         if (!device)
 818                 return -EINVAL;
 819
 820         ec = acpi_driver_data(device);
 821
 822         if (!ec)
 823                 return -EINVAL;
 824
 825         /* Boot EC is already working */
 826         if (ec != boot_ec)
 827                 ret = ec_install_handlers(ec);
 828
 829         /* EC is fully operational, allow queries */
 830         atomic_set(&ec->query_pending, 0);
 831
 832         return ret;
 833 }
 834
 835 static int acpi_ec_stop(struct acpi_device *device, int type)
 836 {
 837         acpi_status status;
 838         struct acpi_ec *ec;
 839
 840         if (!device)
 841                 return -EINVAL;
 842
 843         ec = acpi_driver_data(device);
 844         if (!ec)
 845                 return -EINVAL;
 846
 847         /* Don't touch boot EC */
 848         if (ec == boot_ec)
 849                 return 0;
 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 = acpi_remove_gpe_handler(NULL, ec->gpe, &acpi_ec_gpe_handler);
 858         if (ACPI_FAILURE(status))
 859                 return -ENODEV;
 860
 861         return 0;
 862 }
 863
 864 int __init acpi_ec_ecdt_probe(void)
 865 {
 866         int ret;
 867         acpi_status status;
 868         struct acpi_table_ecdt *ecdt_ptr;
 869
 870         boot_ec = make_acpi_ec();
 871         if (!boot_ec)
 872                 return -ENOMEM;
 873         /*
 874          * Generate a boot ec context
 875          */
 876         status = acpi_get_table(ACPI_SIG_ECDT, 1,
 877                                 (struct acpi_table_header **)&ecdt_ptr);
 878         if (ACPI_SUCCESS(status)) {
 879                 printk(KERN_INFO PREFIX "EC description table is found, configuring boot EC\n\n");
 880                 boot_ec->command_addr = ecdt_ptr->control.address;
 881                 boot_ec->data_addr = ecdt_ptr->data.address;
 882                 boot_ec->gpe = ecdt_ptr->gpe;
 883                 boot_ec->handle = ACPI_ROOT_OBJECT;
 884         } else {
 885                 printk(KERN_DEBUG PREFIX "Look up EC in DSDT\n");
 886                 status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device,
 887                                                 boot_ec, NULL);
 888                 /* Check that acpi_get_devices actually find something */
 889                 if (ACPI_FAILURE(status) || !boot_ec->handle)
 890                         goto error;
 891         }
 892
 893         ret = ec_install_handlers(boot_ec);
 894         if (!ret) {
 895                 first_ec = boot_ec;
 896                 return 0;
 897         }
 898       error:
 899         kfree(boot_ec);
 900         boot_ec = NULL;
 901
 902         return -ENODEV;
 903 }
 904
 905 static int __init acpi_ec_init(void)
 906 {
 907         int result = 0;
 908
 909         if (acpi_disabled)
 910                 return 0;
 911
 912         acpi_ec_dir = proc_mkdir(ACPI_EC_CLASS, acpi_root_dir);
 913         if (!acpi_ec_dir)
 914                 return -ENODEV;
 915
 916         /* Now register the driver for the EC */
 917         result = acpi_bus_register_driver(&acpi_ec_driver);
 918         if (result < 0) {
 919                 remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
 920                 return -ENODEV;
 921         }
 922
 923         return result;
 924 }
 925
 926 subsys_initcall(acpi_ec_init);
 927
 928 /* EC driver currently not unloadable */
 929 #if 0
 930 static void __exit acpi_ec_exit(void)
 931 {
 932
 933         acpi_bus_unregister_driver(&acpi_ec_driver);
 934
 935         remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
 936
 937         return;
 938 }
 939 #endif                          /* 0 */
 940
 941 static int __init acpi_ec_set_intr_mode(char *str)
 942 {
 943         int intr;
 944
 945         if (!get_option(&str, &intr))
 946                 return 0;
 947
 948         acpi_ec_mode = (intr) ? EC_INTR : EC_POLL;
 949
 950         printk(KERN_NOTICE PREFIX "%s mode.\n", intr ? "interrupt" : "polling");
 951
 952         return 1;
 953 }
 954
 955 __setup("ec_intr=", acpi_ec_set_intr_mode);