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         u8 handlers_installed;
 125 } *boot_ec, *first_ec;
 126
 127 /* --------------------------------------------------------------------------
 128                              Transaction Management
 129    -------------------------------------------------------------------------- */
 130
 131 static inline u8 acpi_ec_read_status(struct acpi_ec *ec)
 132 {
 133         return inb(ec->command_addr);
 134 }
 135
 136 static inline u8 acpi_ec_read_data(struct acpi_ec *ec)
 137 {
 138         return inb(ec->data_addr);
 139 }
 140
 141 static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command)
 142 {
 143         outb(command, ec->command_addr);
 144 }
 145
 146 static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data)
 147 {
 148         outb(data, ec->data_addr);
 149 }
 150
 151 static inline int acpi_ec_check_status(struct acpi_ec *ec, enum ec_event event,
 152                                        unsigned old_count)
 153 {
 154         u8 status = acpi_ec_read_status(ec);
 155         if (old_count == atomic_read(&ec->event_count))
 156                 return 0;
 157         if (event == ACPI_EC_EVENT_OBF_1) {
 158                 if (status & ACPI_EC_FLAG_OBF)
 159                         return 1;
 160         } else if (event == ACPI_EC_EVENT_IBF_0) {
 161                 if (!(status & ACPI_EC_FLAG_IBF))
 162                         return 1;
 163         }
 164
 165         return 0;
 166 }
 167
 168 static int acpi_ec_wait(struct acpi_ec *ec, enum ec_event event,
 169                         unsigned count, int force_poll)
 170 {
 171         if (unlikely(force_poll) || acpi_ec_mode == EC_POLL) {
 172                 unsigned long delay = jiffies + msecs_to_jiffies(ACPI_EC_DELAY);
 173                 while (time_before(jiffies, delay)) {
 174                         if (acpi_ec_check_status(ec, event, 0))
 175                                 return 0;
 176                 }
 177         } else {
 178                 if (wait_event_timeout(ec->wait,
 179                                        acpi_ec_check_status(ec, event, count),
 180                                        msecs_to_jiffies(ACPI_EC_DELAY)) ||
 181                     acpi_ec_check_status(ec, event, 0)) {
 182                         return 0;
 183                 } else {
 184                         printk(KERN_ERR PREFIX "acpi_ec_wait timeout,"
 185                                " status = %d, expect_event = %d\n",
 186                                acpi_ec_read_status(ec), event);
 187                 }
 188         }
 189
 190         return -ETIME;
 191 }
 192
 193 static int acpi_ec_transaction_unlocked(struct acpi_ec *ec, u8 command,
 194                                         const u8 * wdata, unsigned wdata_len,
 195                                         u8 * rdata, unsigned rdata_len,
 196                                         int force_poll)
 197 {
 198         int result = 0;
 199         unsigned count = atomic_read(&ec->event_count);
 200         acpi_ec_write_cmd(ec, command);
 201
 202         for (; wdata_len > 0; --wdata_len) {
 203                 result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0, count, force_poll);
 204                 if (result) {
 205                         printk(KERN_ERR PREFIX
 206                                "write_cmd timeout, command = %d\n", command);
 207                         goto end;
 208                 }
 209                 count = atomic_read(&ec->event_count);
 210                 acpi_ec_write_data(ec, *(wdata++));
 211         }
 212
 213         if (!rdata_len) {
 214                 result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0, count, force_poll);
 215                 if (result) {
 216                         printk(KERN_ERR PREFIX
 217                                "finish-write timeout, command = %d\n", command);
 218                         goto end;
 219                 }
 220         } else if (command == ACPI_EC_COMMAND_QUERY) {
 221                 atomic_set(&ec->query_pending, 0);
 222         }
 223
 224         for (; rdata_len > 0; --rdata_len) {
 225                 result = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF_1, count, force_poll);
 226                 if (result) {
 227                         printk(KERN_ERR PREFIX "read timeout, command = %d\n",
 228                                command);
 229                         goto end;
 230                 }
 231                 count = atomic_read(&ec->event_count);
 232                 *(rdata++) = acpi_ec_read_data(ec);
 233         }
 234       end:
 235         return result;
 236 }
 237
 238 static int acpi_ec_transaction(struct acpi_ec *ec, u8 command,
 239                                const u8 * wdata, unsigned wdata_len,
 240                                u8 * rdata, unsigned rdata_len,
 241                                int force_poll)
 242 {
 243         int status;
 244         u32 glk;
 245
 246         if (!ec || (wdata_len && !wdata) || (rdata_len && !rdata))
 247                 return -EINVAL;
 248
 249         if (rdata)
 250                 memset(rdata, 0, rdata_len);
 251
 252         mutex_lock(&ec->lock);
 253         if (ec->global_lock) {
 254                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 255                 if (ACPI_FAILURE(status)) {
 256                         mutex_unlock(&ec->lock);
 257                         return -ENODEV;
 258                 }
 259         }
 260
 261         /* Make sure GPE is enabled before doing transaction */
 262         acpi_enable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
 263
 264         status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0, 0, 0);
 265         if (status) {
 266                 printk(KERN_ERR PREFIX
 267                        "input buffer is not empty, aborting transaction\n");
 268                 goto end;
 269         }
 270
 271         status = acpi_ec_transaction_unlocked(ec, command,
 272                                               wdata, wdata_len,
 273                                               rdata, rdata_len,
 274                                               force_poll);
 275
 276       end:
 277
 278         if (ec->global_lock)
 279                 acpi_release_global_lock(glk);
 280         mutex_unlock(&ec->lock);
 281
 282         return status;
 283 }
 284
 285 /*
 286  * Note: samsung nv5000 doesn't work with ec burst mode.
 287  * http://bugzilla.kernel.org/show_bug.cgi?id=4980
 288  */
 289 int acpi_ec_burst_enable(struct acpi_ec *ec)
 290 {
 291         u8 d;
 292         return acpi_ec_transaction(ec, ACPI_EC_BURST_ENABLE, NULL, 0, &d, 1, 0);
 293 }
 294
 295 int acpi_ec_burst_disable(struct acpi_ec *ec)
 296 {
 297         return acpi_ec_transaction(ec, ACPI_EC_BURST_DISABLE, NULL, 0, NULL, 0, 0);
 298 }
 299
 300 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 * data)
 301 {
 302         int result;
 303         u8 d;
 304
 305         result = acpi_ec_transaction(ec, ACPI_EC_COMMAND_READ,
 306                                      &address, 1, &d, 1, 0);
 307         *data = d;
 308         return result;
 309 }
 310
 311 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
 312 {
 313         u8 wdata[2] = { address, data };
 314         return acpi_ec_transaction(ec, ACPI_EC_COMMAND_WRITE,
 315                                    wdata, 2, NULL, 0, 0);
 316 }
 317
 318 /*
 319  * Externally callable EC access functions. For now, assume 1 EC only
 320  */
 321 int ec_burst_enable(void)
 322 {
 323         if (!first_ec)
 324                 return -ENODEV;
 325         return acpi_ec_burst_enable(first_ec);
 326 }
 327
 328 EXPORT_SYMBOL(ec_burst_enable);
 329
 330 int ec_burst_disable(void)
 331 {
 332         if (!first_ec)
 333                 return -ENODEV;
 334         return acpi_ec_burst_disable(first_ec);
 335 }
 336
 337 EXPORT_SYMBOL(ec_burst_disable);
 338
 339 int ec_read(u8 addr, u8 * val)
 340 {
 341         int err;
 342         u8 temp_data;
 343
 344         if (!first_ec)
 345                 return -ENODEV;
 346
 347         err = acpi_ec_read(first_ec, addr, &temp_data);
 348
 349         if (!err) {
 350                 *val = temp_data;
 351                 return 0;
 352         } else
 353                 return err;
 354 }
 355
 356 EXPORT_SYMBOL(ec_read);
 357
 358 int ec_write(u8 addr, u8 val)
 359 {
 360         int err;
 361
 362         if (!first_ec)
 363                 return -ENODEV;
 364
 365         err = acpi_ec_write(first_ec, addr, val);
 366
 367         return err;
 368 }
 369
 370 EXPORT_SYMBOL(ec_write);
 371
 372 int ec_transaction(u8 command,
 373                    const u8 * wdata, unsigned wdata_len,
 374                    u8 * rdata, unsigned rdata_len,
 375                    int force_poll)
 376 {
 377         if (!first_ec)
 378                 return -ENODEV;
 379
 380         return acpi_ec_transaction(first_ec, command, wdata,
 381                                    wdata_len, rdata, rdata_len,
 382                                    force_poll);
 383 }
 384
 385 EXPORT_SYMBOL(ec_transaction);
 386
 387 static int acpi_ec_query(struct acpi_ec *ec, u8 * data)
 388 {
 389         int result;
 390         u8 d;
 391
 392         if (!ec || !data)
 393                 return -EINVAL;
 394
 395         /*
 396          * Query the EC to find out which _Qxx method we need to evaluate.
 397          * Note that successful completion of the query causes the ACPI_EC_SCI
 398          * bit to be cleared (and thus clearing the interrupt source).
 399          */
 400
 401         result = acpi_ec_transaction(ec, ACPI_EC_COMMAND_QUERY, NULL, 0, &d, 1, 0);
 402         if (result)
 403                 return result;
 404
 405         if (!d)
 406                 return -ENODATA;
 407
 408         *data = d;
 409         return 0;
 410 }
 411
 412 /* --------------------------------------------------------------------------
 413                                 Event Management
 414    -------------------------------------------------------------------------- */
 415 int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
 416                               acpi_handle handle, acpi_ec_query_func func,
 417                               void *data)
 418 {
 419         struct acpi_ec_query_handler *handler =
 420             kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL);
 421         if (!handler)
 422                 return -ENOMEM;
 423
 424         handler->query_bit = query_bit;
 425         handler->handle = handle;
 426         handler->func = func;
 427         handler->data = data;
 428         mutex_lock(&ec->lock);
 429         list_add(&handler->node, &ec->list);
 430         mutex_unlock(&ec->lock);
 431         return 0;
 432 }
 433
 434 EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler);
 435
 436 void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit)
 437 {
 438         struct acpi_ec_query_handler *handler;
 439         mutex_lock(&ec->lock);
 440         list_for_each_entry(handler, &ec->list, node) {
 441                 if (query_bit == handler->query_bit) {
 442                         list_del(&handler->node);
 443                         kfree(handler);
 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         /* Find and register all query methods */
 684         acpi_walk_namespace(ACPI_TYPE_METHOD, handle, 1,
 685                             acpi_ec_register_query_methods, ec, NULL);
 686         /* Use the global lock for all EC transactions? */
 687         acpi_evaluate_integer(handle, "_GLK", NULL, &ec->global_lock);
 688         ec->handle = handle;
 689         return AE_CTRL_TERMINATE;
 690 }
 691
 692 static void ec_remove_handlers(struct acpi_ec *ec)
 693 {
 694         if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle,
 695                                 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler)))
 696                 printk(KERN_ERR PREFIX "failed to remove space handler\n");
 697         if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe,
 698                                 &acpi_ec_gpe_handler)))
 699                 printk(KERN_ERR PREFIX "failed to remove gpe handler\n");
 700         ec->handlers_installed = 0;
 701 }
 702
 703 static int acpi_ec_add(struct acpi_device *device)
 704 {
 705         struct acpi_ec *ec = NULL;
 706
 707         if (!device)
 708                 return -EINVAL;
 709         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
 710         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
 711
 712         /* Check for boot EC */
 713         if (boot_ec) {
 714                 if (boot_ec->handle == device->handle) {
 715                         /* Pre-loaded EC from DSDT, just move pointer */
 716                         ec = boot_ec;
 717                         boot_ec = NULL;
 718                         goto end;
 719                 } else if (boot_ec->handle == ACPI_ROOT_OBJECT) {
 720                         /* ECDT-based EC, time to shut it down */
 721                         ec_remove_handlers(boot_ec);
 722                         kfree(boot_ec);
 723                         first_ec = boot_ec = NULL;
 724                 }
 725         }
 726
 727         ec = make_acpi_ec();
 728         if (!ec)
 729                 return -ENOMEM;
 730
 731         if (ec_parse_device(device->handle, 0, ec, NULL) !=
 732             AE_CTRL_TERMINATE) {
 733                 kfree(ec);
 734                 return -EINVAL;
 735         }
 736         ec->handle = device->handle;
 737       end:
 738         if (!first_ec)
 739                 first_ec = ec;
 740         acpi_driver_data(device) = ec;
 741         acpi_ec_add_fs(device);
 742         printk(KERN_INFO PREFIX "GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n",
 743                           ec->gpe, ec->command_addr, ec->data_addr);
 744         return 0;
 745 }
 746
 747 static int acpi_ec_remove(struct acpi_device *device, int type)
 748 {
 749         struct acpi_ec *ec;
 750         struct acpi_ec_query_handler *handler, *tmp;
 751
 752         if (!device)
 753                 return -EINVAL;
 754
 755         ec = acpi_driver_data(device);
 756         mutex_lock(&ec->lock);
 757         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
 758                 list_del(&handler->node);
 759                 kfree(handler);
 760         }
 761         mutex_unlock(&ec->lock);
 762         acpi_ec_remove_fs(device);
 763         acpi_driver_data(device) = NULL;
 764         if (ec == first_ec)
 765                 first_ec = NULL;
 766         kfree(ec);
 767         return 0;
 768 }
 769
 770 static acpi_status
 771 ec_parse_io_ports(struct acpi_resource *resource, void *context)
 772 {
 773         struct acpi_ec *ec = context;
 774
 775         if (resource->type != ACPI_RESOURCE_TYPE_IO)
 776                 return AE_OK;
 777
 778         /*
 779          * The first address region returned is the data port, and
 780          * the second address region returned is the status/command
 781          * port.
 782          */
 783         if (ec->data_addr == 0)
 784                 ec->data_addr = resource->data.io.minimum;
 785         else if (ec->command_addr == 0)
 786                 ec->command_addr = resource->data.io.minimum;
 787         else
 788                 return AE_CTRL_TERMINATE;
 789
 790         return AE_OK;
 791 }
 792
 793 static int ec_install_handlers(struct acpi_ec *ec)
 794 {
 795         acpi_status status;
 796         if (ec->handlers_installed)
 797                 return 0;
 798         status = acpi_install_gpe_handler(NULL, ec->gpe,
 799                                           ACPI_GPE_EDGE_TRIGGERED,
 800                                           &acpi_ec_gpe_handler, ec);
 801         if (ACPI_FAILURE(status))
 802                 return -ENODEV;
 803
 804         acpi_set_gpe_type(NULL, ec->gpe, ACPI_GPE_TYPE_RUNTIME);
 805         acpi_enable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
 806
 807         status = acpi_install_address_space_handler(ec->handle,
 808                                                     ACPI_ADR_SPACE_EC,
 809                                                     &acpi_ec_space_handler,
 810                                                     &acpi_ec_space_setup, ec);
 811         if (ACPI_FAILURE(status)) {
 812                 acpi_remove_gpe_handler(NULL, ec->gpe, &acpi_ec_gpe_handler);
 813                 return -ENODEV;
 814         }
 815
 816         ec->handlers_installed = 1;
 817         return 0;
 818 }
 819
 820 static int acpi_ec_start(struct acpi_device *device)
 821 {
 822         struct acpi_ec *ec;
 823         int ret = 0;
 824
 825         if (!device)
 826                 return -EINVAL;
 827
 828         ec = acpi_driver_data(device);
 829
 830         if (!ec)
 831                 return -EINVAL;
 832
 833         ret = ec_install_handlers(ec);
 834
 835         /* EC is fully operational, allow queries */
 836         atomic_set(&ec->query_pending, 0);
 837         return ret;
 838 }
 839
 840 static int acpi_ec_stop(struct acpi_device *device, int type)
 841 {
 842         struct acpi_ec *ec;
 843         if (!device)
 844                 return -EINVAL;
 845         ec = acpi_driver_data(device);
 846         if (!ec)
 847                 return -EINVAL;
 848         ec_remove_handlers(ec);
 849
 850         return 0;
 851 }
 852
 853 int __init acpi_ec_ecdt_probe(void)
 854 {
 855         int ret;
 856         acpi_status status;
 857         struct acpi_table_ecdt *ecdt_ptr;
 858
 859         boot_ec = make_acpi_ec();
 860         if (!boot_ec)
 861                 return -ENOMEM;
 862         /*
 863          * Generate a boot ec context
 864          */
 865         status = acpi_get_table(ACPI_SIG_ECDT, 1,
 866                                 (struct acpi_table_header **)&ecdt_ptr);
 867         if (ACPI_SUCCESS(status)) {
 868                 printk(KERN_INFO PREFIX "EC description table is found, configuring boot EC\n");
 869                 boot_ec->command_addr = ecdt_ptr->control.address;
 870                 boot_ec->data_addr = ecdt_ptr->data.address;
 871                 boot_ec->gpe = ecdt_ptr->gpe;
 872                 boot_ec->handle = ACPI_ROOT_OBJECT;
 873         } else {
 874                 printk(KERN_DEBUG PREFIX "Look up EC in DSDT\n");
 875                 status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device,
 876                                                 boot_ec, NULL);
 877                 /* Check that acpi_get_devices actually find something */
 878                 if (ACPI_FAILURE(status) || !boot_ec->handle)
 879                         goto error;
 880         }
 881
 882         ret = ec_install_handlers(boot_ec);
 883         if (!ret) {
 884                 first_ec = boot_ec;
 885                 return 0;
 886         }
 887       error:
 888         kfree(boot_ec);
 889         boot_ec = NULL;
 890         return -ENODEV;
 891 }
 892
 893 static int __init acpi_ec_init(void)
 894 {
 895         int result = 0;
 896
 897         if (acpi_disabled)
 898                 return 0;
 899
 900         acpi_ec_dir = proc_mkdir(ACPI_EC_CLASS, acpi_root_dir);
 901         if (!acpi_ec_dir)
 902                 return -ENODEV;
 903
 904         /* Now register the driver for the EC */
 905         result = acpi_bus_register_driver(&acpi_ec_driver);
 906         if (result < 0) {
 907                 remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
 908                 return -ENODEV;
 909         }
 910
 911         return result;
 912 }
 913
 914 subsys_initcall(acpi_ec_init);
 915
 916 /* EC driver currently not unloadable */
 917 #if 0
 918 static void __exit acpi_ec_exit(void)
 919 {
 920
 921         acpi_bus_unregister_driver(&acpi_ec_driver);
 922
 923         remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
 924
 925         return;
 926 }
 927 #endif                          /* 0 */
 928
 929 static int __init acpi_ec_set_intr_mode(char *str)
 930 {
 931         int intr;
 932
 933         if (!get_option(&str, &intr))
 934                 return 0;
 935
 936         acpi_ec_mode = (intr) ? EC_INTR : EC_POLL;
 937
 938         printk(KERN_NOTICE PREFIX "%s mode.\n", intr ? "interrupt" : "polling");
 939
 940         return 1;
 941 }
 942
 943 __setup("ec_intr=", acpi_ec_set_intr_mode);