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_tail(&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                         break;
 444                 }
 445         }
 446         mutex_unlock(&ec->lock);
 447 }
 448
 449 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler);
 450
 451 static void acpi_ec_gpe_query(void *ec_cxt)
 452 {
 453         struct acpi_ec *ec = ec_cxt;
 454         u8 value = 0;
 455         struct acpi_ec_query_handler *handler, copy;
 456
 457         if (!ec || acpi_ec_query(ec, &value))
 458                 return;
 459         mutex_lock(&ec->lock);
 460         list_for_each_entry(handler, &ec->list, node) {
 461                 if (value == handler->query_bit) {
 462                         /* have custom handler for this bit */
 463                         memcpy(&copy, handler, sizeof(copy));
 464                         mutex_unlock(&ec->lock);
 465                         if (copy.func) {
 466                                 copy.func(copy.data);
 467                         } else if (copy.handle) {
 468                                 acpi_evaluate_object(copy.handle, NULL, NULL, NULL);
 469                         }
 470                         return;
 471                 }
 472         }
 473         mutex_unlock(&ec->lock);
 474 }
 475
 476 static u32 acpi_ec_gpe_handler(void *data)
 477 {
 478         acpi_status status = AE_OK;
 479         u8 value;
 480         struct acpi_ec *ec = data;
 481
 482         atomic_inc(&ec->event_count);
 483
 484         if (acpi_ec_mode == EC_INTR) {
 485                 wake_up(&ec->wait);
 486         }
 487
 488         value = acpi_ec_read_status(ec);
 489         if ((value & ACPI_EC_FLAG_SCI) && !atomic_read(&ec->query_pending)) {
 490                 atomic_set(&ec->query_pending, 1);
 491                 status =
 492                     acpi_os_execute(OSL_EC_BURST_HANDLER, acpi_ec_gpe_query, ec);
 493         }
 494
 495         return status == AE_OK ?
 496             ACPI_INTERRUPT_HANDLED : ACPI_INTERRUPT_NOT_HANDLED;
 497 }
 498
 499 /* --------------------------------------------------------------------------
 500                              Address Space Management
 501    -------------------------------------------------------------------------- */
 502
 503 static acpi_status
 504 acpi_ec_space_setup(acpi_handle region_handle,
 505                     u32 function, void *handler_context, void **return_context)
 506 {
 507         /*
 508          * The EC object is in the handler context and is needed
 509          * when calling the acpi_ec_space_handler.
 510          */
 511         *return_context = (function != ACPI_REGION_DEACTIVATE) ?
 512             handler_context : NULL;
 513
 514         return AE_OK;
 515 }
 516
 517 static acpi_status
 518 acpi_ec_space_handler(u32 function, acpi_physical_address address,
 519                       u32 bits, acpi_integer *value,
 520                       void *handler_context, void *region_context)
 521 {
 522         struct acpi_ec *ec = handler_context;
 523         int result = 0, i = 0;
 524         u8 temp = 0;
 525
 526         if ((address > 0xFF) || !value || !handler_context)
 527                 return AE_BAD_PARAMETER;
 528
 529         if (function != ACPI_READ && function != ACPI_WRITE)
 530                 return AE_BAD_PARAMETER;
 531
 532         if (bits != 8 && acpi_strict)
 533                 return AE_BAD_PARAMETER;
 534
 535         while (bits - i > 0) {
 536                 if (function == ACPI_READ) {
 537                         result = acpi_ec_read(ec, address, &temp);
 538                         (*value) |= ((acpi_integer)temp) << i;
 539                 } else {
 540                         temp = 0xff & ((*value) >> i);
 541                         result = acpi_ec_write(ec, address, temp);
 542                 }
 543                 i += 8;
 544                 ++address;
 545         }
 546
 547         switch (result) {
 548         case -EINVAL:
 549                 return AE_BAD_PARAMETER;
 550                 break;
 551         case -ENODEV:
 552                 return AE_NOT_FOUND;
 553                 break;
 554         case -ETIME:
 555                 return AE_TIME;
 556                 break;
 557         default:
 558                 return AE_OK;
 559         }
 560 }
 561
 562 /* --------------------------------------------------------------------------
 563                               FS Interface (/proc)
 564    -------------------------------------------------------------------------- */
 565
 566 static struct proc_dir_entry *acpi_ec_dir;
 567
 568 static int acpi_ec_read_info(struct seq_file *seq, void *offset)
 569 {
 570         struct acpi_ec *ec = seq->private;
 571
 572         if (!ec)
 573                 goto end;
 574
 575         seq_printf(seq, "gpe:\t\t\t0x%02x\n", (u32) ec->gpe);
 576         seq_printf(seq, "ports:\t\t\t0x%02x, 0x%02x\n",
 577                    (unsigned)ec->command_addr, (unsigned)ec->data_addr);
 578         seq_printf(seq, "use global lock:\t%s\n",
 579                    ec->global_lock ? "yes" : "no");
 580       end:
 581         return 0;
 582 }
 583
 584 static int acpi_ec_info_open_fs(struct inode *inode, struct file *file)
 585 {
 586         return single_open(file, acpi_ec_read_info, PDE(inode)->data);
 587 }
 588
 589 static struct file_operations acpi_ec_info_ops = {
 590         .open = acpi_ec_info_open_fs,
 591         .read = seq_read,
 592         .llseek = seq_lseek,
 593         .release = single_release,
 594         .owner = THIS_MODULE,
 595 };
 596
 597 static int acpi_ec_add_fs(struct acpi_device *device)
 598 {
 599         struct proc_dir_entry *entry = NULL;
 600
 601         if (!acpi_device_dir(device)) {
 602                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
 603                                                      acpi_ec_dir);
 604                 if (!acpi_device_dir(device))
 605                         return -ENODEV;
 606         }
 607
 608         entry = create_proc_entry(ACPI_EC_FILE_INFO, S_IRUGO,
 609                                   acpi_device_dir(device));
 610         if (!entry)
 611                 return -ENODEV;
 612         else {
 613                 entry->proc_fops = &acpi_ec_info_ops;
 614                 entry->data = acpi_driver_data(device);
 615                 entry->owner = THIS_MODULE;
 616         }
 617
 618         return 0;
 619 }
 620
 621 static int acpi_ec_remove_fs(struct acpi_device *device)
 622 {
 623
 624         if (acpi_device_dir(device)) {
 625                 remove_proc_entry(ACPI_EC_FILE_INFO, acpi_device_dir(device));
 626                 remove_proc_entry(acpi_device_bid(device), acpi_ec_dir);
 627                 acpi_device_dir(device) = NULL;
 628         }
 629
 630         return 0;
 631 }
 632
 633 /* --------------------------------------------------------------------------
 634                                Driver Interface
 635    -------------------------------------------------------------------------- */
 636 static acpi_status
 637 ec_parse_io_ports(struct acpi_resource *resource, void *context);
 638
 639 static struct acpi_ec *make_acpi_ec(void)
 640 {
 641         struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
 642         if (!ec)
 643                 return NULL;
 644
 645         atomic_set(&ec->query_pending, 1);
 646         atomic_set(&ec->event_count, 1);
 647         mutex_init(&ec->lock);
 648         init_waitqueue_head(&ec->wait);
 649         INIT_LIST_HEAD(&ec->list);
 650
 651         return ec;
 652 }
 653
 654 static acpi_status
 655 acpi_ec_register_query_methods(acpi_handle handle, u32 level,
 656                                void *context, void **return_value)
 657 {
 658         struct acpi_namespace_node *node = handle;
 659         struct acpi_ec *ec = context;
 660         int value = 0;
 661         if (sscanf(node->name.ascii, "_Q%x", &value) == 1) {
 662                 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL);
 663         }
 664         return AE_OK;
 665 }
 666
 667 static acpi_status
 668 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
 669 {
 670         acpi_status status;
 671
 672         struct acpi_ec *ec = context;
 673         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
 674                                      ec_parse_io_ports, ec);
 675         if (ACPI_FAILURE(status))
 676                 return status;
 677
 678         /* Get GPE bit assignment (EC events). */
 679         /* TODO: Add support for _GPE returning a package */
 680         status = acpi_evaluate_integer(handle, "_GPE", NULL, &ec->gpe);
 681         if (ACPI_FAILURE(status))
 682                 return status;
 683
 684         /* Find and register all query methods */
 685         acpi_walk_namespace(ACPI_TYPE_METHOD, handle, 1,
 686                             acpi_ec_register_query_methods, ec, NULL);
 687
 688         /* Use the global lock for all EC transactions? */
 689         acpi_evaluate_integer(handle, "_GLK", NULL, &ec->global_lock);
 690
 691         ec->handle = handle;
 692
 693         printk(KERN_INFO PREFIX "GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n",
 694                           ec->gpe, ec->command_addr, ec->data_addr);
 695
 696         return AE_CTRL_TERMINATE;
 697 }
 698
 699 static int acpi_ec_add(struct acpi_device *device)
 700 {
 701         struct acpi_ec *ec = NULL;
 702
 703         if (!device)
 704                 return -EINVAL;
 705
 706         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
 707         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
 708
 709         ec = make_acpi_ec();
 710         if (!ec)
 711                 return -ENOMEM;
 712
 713         if (ec_parse_device(device->handle, 0, ec, NULL) !=
 714             AE_CTRL_TERMINATE) {
 715                 kfree(ec);
 716                 return -EINVAL;
 717         }
 718
 719         /* Check if we found the boot EC */
 720         if (boot_ec) {
 721                 if (boot_ec->gpe == ec->gpe) {
 722                         /* We might have incorrect info for GL at boot time */
 723                         mutex_lock(&boot_ec->lock);
 724                         boot_ec->global_lock = ec->global_lock;
 725                         /* Copy handlers from new ec into boot ec */
 726                         list_splice(&ec->list, &boot_ec->list);
 727                         mutex_unlock(&boot_ec->lock);
 728                         kfree(ec);
 729                         ec = boot_ec;
 730                 }
 731         } else
 732                 first_ec = ec;
 733         ec->handle = device->handle;
 734         acpi_driver_data(device) = ec;
 735
 736         acpi_ec_add_fs(device);
 737         return 0;
 738 }
 739
 740 static int acpi_ec_remove(struct acpi_device *device, int type)
 741 {
 742         struct acpi_ec *ec;
 743         struct acpi_ec_query_handler *handler, *tmp;
 744
 745         if (!device)
 746                 return -EINVAL;
 747
 748         ec = acpi_driver_data(device);
 749         mutex_lock(&ec->lock);
 750         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
 751                 list_del(&handler->node);
 752                 kfree(handler);
 753         }
 754         mutex_unlock(&ec->lock);
 755         acpi_ec_remove_fs(device);
 756         acpi_driver_data(device) = NULL;
 757         if (ec == first_ec)
 758                 first_ec = NULL;
 759
 760         /* Don't touch boot EC */
 761         if (boot_ec != ec)
 762                 kfree(ec);
 763         return 0;
 764 }
 765
 766 static acpi_status
 767 ec_parse_io_ports(struct acpi_resource *resource, void *context)
 768 {
 769         struct acpi_ec *ec = context;
 770
 771         if (resource->type != ACPI_RESOURCE_TYPE_IO)
 772                 return AE_OK;
 773
 774         /*
 775          * The first address region returned is the data port, and
 776          * the second address region returned is the status/command
 777          * port.
 778          */
 779         if (ec->data_addr == 0)
 780                 ec->data_addr = resource->data.io.minimum;
 781         else if (ec->command_addr == 0)
 782                 ec->command_addr = resource->data.io.minimum;
 783         else
 784                 return AE_CTRL_TERMINATE;
 785
 786         return AE_OK;
 787 }
 788
 789 static int ec_install_handlers(struct acpi_ec *ec)
 790 {
 791         acpi_status status;
 792         status = acpi_install_gpe_handler(NULL, ec->gpe,
 793                                           ACPI_GPE_EDGE_TRIGGERED,
 794                                           &acpi_ec_gpe_handler, ec);
 795         if (ACPI_FAILURE(status))
 796                 return -ENODEV;
 797
 798         acpi_set_gpe_type(NULL, ec->gpe, ACPI_GPE_TYPE_RUNTIME);
 799         acpi_enable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
 800
 801         status = acpi_install_address_space_handler(ec->handle,
 802                                                     ACPI_ADR_SPACE_EC,
 803                                                     &acpi_ec_space_handler,
 804                                                     &acpi_ec_space_setup, ec);
 805         if (ACPI_FAILURE(status)) {
 806                 acpi_remove_gpe_handler(NULL, ec->gpe, &acpi_ec_gpe_handler);
 807                 return -ENODEV;
 808         }
 809
 810         return 0;
 811 }
 812
 813 static int acpi_ec_start(struct acpi_device *device)
 814 {
 815         struct acpi_ec *ec;
 816         int ret = 0;
 817
 818         if (!device)
 819                 return -EINVAL;
 820
 821         ec = acpi_driver_data(device);
 822
 823         if (!ec)
 824                 return -EINVAL;
 825
 826         /* Boot EC is already working */
 827         if (ec != boot_ec)
 828                 ret = ec_install_handlers(ec);
 829
 830         /* EC is fully operational, allow queries */
 831         atomic_set(&ec->query_pending, 0);
 832
 833         return ret;
 834 }
 835
 836 static int acpi_ec_stop(struct acpi_device *device, int type)
 837 {
 838         acpi_status status;
 839         struct acpi_ec *ec;
 840
 841         if (!device)
 842                 return -EINVAL;
 843
 844         ec = acpi_driver_data(device);
 845         if (!ec)
 846                 return -EINVAL;
 847
 848         /* Don't touch boot EC */
 849         if (ec == boot_ec)
 850                 return 0;
 851
 852         status = acpi_remove_address_space_handler(ec->handle,
 853                                                    ACPI_ADR_SPACE_EC,
 854                                                    &acpi_ec_space_handler);
 855         if (ACPI_FAILURE(status))
 856                 return -ENODEV;
 857
 858         status = acpi_remove_gpe_handler(NULL, ec->gpe, &acpi_ec_gpe_handler);
 859         if (ACPI_FAILURE(status))
 860                 return -ENODEV;
 861
 862         return 0;
 863 }
 864
 865 int __init acpi_ec_ecdt_probe(void)
 866 {
 867         int ret;
 868         acpi_status status;
 869         struct acpi_table_ecdt *ecdt_ptr;
 870
 871         boot_ec = make_acpi_ec();
 872         if (!boot_ec)
 873                 return -ENOMEM;
 874         /*
 875          * Generate a boot ec context
 876          */
 877         status = acpi_get_table(ACPI_SIG_ECDT, 1,
 878                                 (struct acpi_table_header **)&ecdt_ptr);
 879         if (ACPI_SUCCESS(status)) {
 880                 printk(KERN_INFO PREFIX "EC description table is found, configuring boot EC\n\n");
 881                 boot_ec->command_addr = ecdt_ptr->control.address;
 882                 boot_ec->data_addr = ecdt_ptr->data.address;
 883                 boot_ec->gpe = ecdt_ptr->gpe;
 884                 boot_ec->handle = ACPI_ROOT_OBJECT;
 885         } else {
 886                 printk(KERN_DEBUG PREFIX "Look up EC in DSDT\n");
 887                 status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device,
 888                                                 boot_ec, NULL);
 889                 /* Check that acpi_get_devices actually find something */
 890                 if (ACPI_FAILURE(status) || !boot_ec->handle)
 891                         goto error;
 892         }
 893
 894         ret = ec_install_handlers(boot_ec);
 895         if (!ret) {
 896                 first_ec = boot_ec;
 897                 return 0;
 898         }
 899       error:
 900         kfree(boot_ec);
 901         boot_ec = NULL;
 902
 903         return -ENODEV;
 904 }
 905
 906 static int __init acpi_ec_init(void)
 907 {
 908         int result = 0;
 909
 910         if (acpi_disabled)
 911                 return 0;
 912
 913         acpi_ec_dir = proc_mkdir(ACPI_EC_CLASS, acpi_root_dir);
 914         if (!acpi_ec_dir)
 915                 return -ENODEV;
 916
 917         /* Now register the driver for the EC */
 918         result = acpi_bus_register_driver(&acpi_ec_driver);
 919         if (result < 0) {
 920                 remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
 921                 return -ENODEV;
 922         }
 923
 924         return result;
 925 }
 926
 927 subsys_initcall(acpi_ec_init);
 928
 929 /* EC driver currently not unloadable */
 930 #if 0
 931 static void __exit acpi_ec_exit(void)
 932 {
 933
 934         acpi_bus_unregister_driver(&acpi_ec_driver);
 935
 936         remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
 937
 938         return;
 939 }
 940 #endif                          /* 0 */
 941
 942 static int __init acpi_ec_set_intr_mode(char *str)
 943 {
 944         int intr;
 945
 946         if (!get_option(&str, &intr))
 947                 return 0;
 948
 949         acpi_ec_mode = (intr) ? EC_INTR : EC_POLL;
 950
 951         printk(KERN_NOTICE PREFIX "%s mode.\n", intr ? "interrupt" : "polling");
 952
 953         return 1;
 954 }
 955
 956 __setup("ec_intr=", acpi_ec_set_intr_mode);