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 /* Uncomment next line to get verbose print outs*/
  51 /* #define DEBUG */
  52
  53 /* EC status register */
  54 #define ACPI_EC_FLAG_OBF        0x01    /* Output buffer full */
  55 #define ACPI_EC_FLAG_IBF        0x02    /* Input buffer full */
  56 #define ACPI_EC_FLAG_BURST      0x10    /* burst mode */
  57 #define ACPI_EC_FLAG_SCI        0x20    /* EC-SCI occurred */
  58
  59 /* EC commands */
  60 enum ec_command {
  61         ACPI_EC_COMMAND_READ = 0x80,
  62         ACPI_EC_COMMAND_WRITE = 0x81,
  63         ACPI_EC_BURST_ENABLE = 0x82,
  64         ACPI_EC_BURST_DISABLE = 0x83,
  65         ACPI_EC_COMMAND_QUERY = 0x84,
  66 };
  67
  68 /* EC events */
  69 enum ec_event {
  70         ACPI_EC_EVENT_OBF_1 = 1,        /* Output buffer full */
  71         ACPI_EC_EVENT_IBF_0,            /* Input buffer empty */
  72 };
  73
  74 #define ACPI_EC_DELAY           500     /* Wait 500ms max. during EC ops */
  75 #define ACPI_EC_UDELAY_GLK      1000    /* Wait 1ms max. to get global lock */
  76
  77 enum {
  78         EC_FLAGS_WAIT_GPE = 0,          /* Don't check status until GPE arrives */
  79         EC_FLAGS_QUERY_PENDING,         /* Query is pending */
  80         EC_FLAGS_GPE_MODE,              /* Expect GPE to be sent for status change */
  81         EC_FLAGS_NO_ADDRESS_GPE,        /* Expect GPE only for non-address event */
  82         EC_FLAGS_ADDRESS,               /* Address is being written */
  83         EC_FLAGS_NO_WDATA_GPE,          /* Don't expect WDATA GPE event */
  84         EC_FLAGS_WDATA,                 /* Data is being written */
  85 };
  86
  87 static int acpi_ec_remove(struct acpi_device *device, int type);
  88 static int acpi_ec_start(struct acpi_device *device);
  89 static int acpi_ec_stop(struct acpi_device *device, int type);
  90 static int acpi_ec_add(struct acpi_device *device);
  91
  92 static const struct acpi_device_id ec_device_ids[] = {
  93         {"PNP0C09", 0},
  94         {"", 0},
  95 };
  96
  97 static struct acpi_driver acpi_ec_driver = {
  98         .name = "ec",
  99         .class = ACPI_EC_CLASS,
 100         .ids = ec_device_ids,
 101         .ops = {
 102                 .add = acpi_ec_add,
 103                 .remove = acpi_ec_remove,
 104                 .start = acpi_ec_start,
 105                 .stop = acpi_ec_stop,
 106                 },
 107 };
 108
 109 /* If we find an EC via the ECDT, we need to keep a ptr to its context */
 110 /* External interfaces use first EC only, so remember */
 111 typedef int (*acpi_ec_query_func) (void *data);
 112
 113 struct acpi_ec_query_handler {
 114         struct list_head node;
 115         acpi_ec_query_func func;
 116         acpi_handle handle;
 117         void *data;
 118         u8 query_bit;
 119 };
 120
 121 static struct acpi_ec {
 122         acpi_handle handle;
 123         unsigned long gpe;
 124         unsigned long command_addr;
 125         unsigned long data_addr;
 126         unsigned long global_lock;
 127         unsigned long flags;
 128         struct mutex lock;
 129         wait_queue_head_t wait;
 130         struct list_head list;
 131         u8 handlers_installed;
 132 } *boot_ec, *first_ec;
 133
 134 /* --------------------------------------------------------------------------
 135                              Transaction Management
 136    -------------------------------------------------------------------------- */
 137
 138 static inline u8 acpi_ec_read_status(struct acpi_ec *ec)
 139 {
 140         u8 x = inb(ec->command_addr);
 141         pr_debug(PREFIX "---> status = 0x%2x\n", x);
 142         return x;
 143 }
 144
 145 static inline u8 acpi_ec_read_data(struct acpi_ec *ec)
 146 {
 147         u8 x = inb(ec->data_addr);
 148         pr_debug(PREFIX "---> data = 0x%2x\n", x);
 149         return inb(ec->data_addr);
 150 }
 151
 152 static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command)
 153 {
 154         pr_debug(PREFIX "<--- command = 0x%2x\n", command);
 155         outb(command, ec->command_addr);
 156 }
 157
 158 static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data)
 159 {
 160         pr_debug(PREFIX "<--- data = 0x%2x\n", data);
 161         outb(data, ec->data_addr);
 162 }
 163
 164 static inline int acpi_ec_check_status(struct acpi_ec *ec, enum ec_event event)
 165 {
 166         if (test_bit(EC_FLAGS_WAIT_GPE, &ec->flags))
 167                 return 0;
 168         if (event == ACPI_EC_EVENT_OBF_1) {
 169                 if (acpi_ec_read_status(ec) & ACPI_EC_FLAG_OBF)
 170                         return 1;
 171         } else if (event == ACPI_EC_EVENT_IBF_0) {
 172                 if (!(acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF))
 173                         return 1;
 174         }
 175
 176         return 0;
 177 }
 178
 179 static int acpi_ec_wait(struct acpi_ec *ec, enum ec_event event, int force_poll)
 180 {
 181         int ret = 0;
 182         if (unlikely(test_bit(EC_FLAGS_ADDRESS, &ec->flags) &&
 183                      test_bit(EC_FLAGS_NO_ADDRESS_GPE, &ec->flags)))
 184                 force_poll = 1;
 185         if (unlikely(test_bit(EC_FLAGS_WDATA, &ec->flags) &&
 186                      test_bit(EC_FLAGS_NO_WDATA_GPE, &ec->flags)))
 187                 force_poll = 1;
 188         if (likely(test_bit(EC_FLAGS_GPE_MODE, &ec->flags)) &&
 189             likely(!force_poll)) {
 190                 if (wait_event_timeout(ec->wait, acpi_ec_check_status(ec, event),
 191                                        msecs_to_jiffies(ACPI_EC_DELAY)))
 192                         goto end;
 193                 clear_bit(EC_FLAGS_WAIT_GPE, &ec->flags);
 194                 if (acpi_ec_check_status(ec, event)) {
 195                         if (test_bit(EC_FLAGS_ADDRESS, &ec->flags)) {
 196                                 /* miss address GPE, don't expect it anymore */
 197                                 pr_info(PREFIX "missing address confirmation, "
 198                                         "don't expect it any longer.\n");
 199                                 set_bit(EC_FLAGS_NO_ADDRESS_GPE, &ec->flags);
 200                         } else if (test_bit(EC_FLAGS_WDATA, &ec->flags)) {
 201                                 /* miss write data GPE, don't expect it */
 202                                 pr_info(PREFIX "missing write data confirmation, "
 203                                         "don't expect it any longer.\n");
 204                                 set_bit(EC_FLAGS_NO_WDATA_GPE, &ec->flags);
 205                         } else {
 206                                 /* missing GPEs, switch back to poll mode */
 207                                 if (printk_ratelimit())
 208                                         pr_info(PREFIX "missing confirmations, "
 209                                                 "switch off interrupt mode.\n");
 210                                 clear_bit(EC_FLAGS_GPE_MODE, &ec->flags);
 211                         }
 212                         goto end;
 213                 }
 214         } else {
 215                 unsigned long delay = jiffies + msecs_to_jiffies(ACPI_EC_DELAY);
 216                 clear_bit(EC_FLAGS_WAIT_GPE, &ec->flags);
 217                 while (time_before(jiffies, delay)) {
 218                         if (acpi_ec_check_status(ec, event))
 219                                 goto end;
 220                 }
 221         }
 222         pr_err(PREFIX "acpi_ec_wait timeout,"
 223                                " status = %d, expect_event = %d\n",
 224                                acpi_ec_read_status(ec), event);
 225         ret = -ETIME;
 226       end:
 227         clear_bit(EC_FLAGS_ADDRESS, &ec->flags);
 228         return ret;
 229 }
 230
 231 static int acpi_ec_transaction_unlocked(struct acpi_ec *ec, u8 command,
 232                                         const u8 * wdata, unsigned wdata_len,
 233                                         u8 * rdata, unsigned rdata_len,
 234                                         int force_poll)
 235 {
 236         int result = 0;
 237         set_bit(EC_FLAGS_WAIT_GPE, &ec->flags);
 238         acpi_ec_write_cmd(ec, command);
 239         pr_debug(PREFIX "transaction start\n");
 240         for (; wdata_len > 0; --wdata_len) {
 241                 result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0, force_poll);
 242                 if (result) {
 243                         pr_err(PREFIX
 244                                "write_cmd timeout, command = %d\n", command);
 245                         goto end;
 246                 }
 247                 /* mark the address byte written to EC */
 248                 if (rdata_len + wdata_len > 1)
 249                         set_bit(EC_FLAGS_ADDRESS, &ec->flags);
 250                 set_bit(EC_FLAGS_WAIT_GPE, &ec->flags);
 251                 acpi_ec_write_data(ec, *(wdata++));
 252         }
 253
 254         if (!rdata_len) {
 255                 set_bit(EC_FLAGS_WDATA, &ec->flags);
 256                 result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0, force_poll);
 257                 if (result) {
 258                         pr_err(PREFIX
 259                                "finish-write timeout, command = %d\n", command);
 260                         goto end;
 261                 }
 262         } else if (command == ACPI_EC_COMMAND_QUERY)
 263                 clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
 264
 265         for (; rdata_len > 0; --rdata_len) {
 266                 result = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF_1, force_poll);
 267                 if (result) {
 268                         pr_err(PREFIX "read timeout, command = %d\n", command);
 269                         goto end;
 270                 }
 271                 /* Don't expect GPE after last read */
 272                 if (rdata_len > 1)
 273                         set_bit(EC_FLAGS_WAIT_GPE, &ec->flags);
 274                 *(rdata++) = acpi_ec_read_data(ec);
 275         }
 276       end:
 277         pr_debug(PREFIX "transaction end\n");
 278         return result;
 279 }
 280
 281 static int acpi_ec_transaction(struct acpi_ec *ec, u8 command,
 282                                const u8 * wdata, unsigned wdata_len,
 283                                u8 * rdata, unsigned rdata_len,
 284                                int force_poll)
 285 {
 286         int status;
 287         u32 glk;
 288
 289         if (!ec || (wdata_len && !wdata) || (rdata_len && !rdata))
 290                 return -EINVAL;
 291
 292         if (rdata)
 293                 memset(rdata, 0, rdata_len);
 294
 295         mutex_lock(&ec->lock);
 296         if (ec->global_lock) {
 297                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 298                 if (ACPI_FAILURE(status)) {
 299                         mutex_unlock(&ec->lock);
 300                         return -ENODEV;
 301                 }
 302         }
 303
 304         status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0, 0);
 305         if (status) {
 306                 pr_err(PREFIX "input buffer is not empty, "
 307                                 "aborting transaction\n");
 308                 goto end;
 309         }
 310
 311         status = acpi_ec_transaction_unlocked(ec, command,
 312                                               wdata, wdata_len,
 313                                               rdata, rdata_len,
 314                                               force_poll);
 315
 316       end:
 317
 318         if (ec->global_lock)
 319                 acpi_release_global_lock(glk);
 320         mutex_unlock(&ec->lock);
 321
 322         return status;
 323 }
 324
 325 /*
 326  * Note: samsung nv5000 doesn't work with ec burst mode.
 327  * http://bugzilla.kernel.org/show_bug.cgi?id=4980
 328  */
 329 int acpi_ec_burst_enable(struct acpi_ec *ec)
 330 {
 331         u8 d;
 332         return acpi_ec_transaction(ec, ACPI_EC_BURST_ENABLE, NULL, 0, &d, 1, 0);
 333 }
 334
 335 int acpi_ec_burst_disable(struct acpi_ec *ec)
 336 {
 337         return acpi_ec_transaction(ec, ACPI_EC_BURST_DISABLE, NULL, 0, NULL, 0, 0);
 338 }
 339
 340 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 * data)
 341 {
 342         int result;
 343         u8 d;
 344
 345         result = acpi_ec_transaction(ec, ACPI_EC_COMMAND_READ,
 346                                      &address, 1, &d, 1, 0);
 347         *data = d;
 348         return result;
 349 }
 350
 351 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
 352 {
 353         u8 wdata[2] = { address, data };
 354         return acpi_ec_transaction(ec, ACPI_EC_COMMAND_WRITE,
 355                                    wdata, 2, NULL, 0, 0);
 356 }
 357
 358 /*
 359  * Externally callable EC access functions. For now, assume 1 EC only
 360  */
 361 int ec_burst_enable(void)
 362 {
 363         if (!first_ec)
 364                 return -ENODEV;
 365         return acpi_ec_burst_enable(first_ec);
 366 }
 367
 368 EXPORT_SYMBOL(ec_burst_enable);
 369
 370 int ec_burst_disable(void)
 371 {
 372         if (!first_ec)
 373                 return -ENODEV;
 374         return acpi_ec_burst_disable(first_ec);
 375 }
 376
 377 EXPORT_SYMBOL(ec_burst_disable);
 378
 379 int ec_read(u8 addr, u8 * val)
 380 {
 381         int err;
 382         u8 temp_data;
 383
 384         if (!first_ec)
 385                 return -ENODEV;
 386
 387         err = acpi_ec_read(first_ec, addr, &temp_data);
 388
 389         if (!err) {
 390                 *val = temp_data;
 391                 return 0;
 392         } else
 393                 return err;
 394 }
 395
 396 EXPORT_SYMBOL(ec_read);
 397
 398 int ec_write(u8 addr, u8 val)
 399 {
 400         int err;
 401
 402         if (!first_ec)
 403                 return -ENODEV;
 404
 405         err = acpi_ec_write(first_ec, addr, val);
 406
 407         return err;
 408 }
 409
 410 EXPORT_SYMBOL(ec_write);
 411
 412 int ec_transaction(u8 command,
 413                    const u8 * wdata, unsigned wdata_len,
 414                    u8 * rdata, unsigned rdata_len,
 415                    int force_poll)
 416 {
 417         if (!first_ec)
 418                 return -ENODEV;
 419
 420         return acpi_ec_transaction(first_ec, command, wdata,
 421                                    wdata_len, rdata, rdata_len,
 422                                    force_poll);
 423 }
 424
 425 EXPORT_SYMBOL(ec_transaction);
 426
 427 static int acpi_ec_query(struct acpi_ec *ec, u8 * data)
 428 {
 429         int result;
 430         u8 d;
 431
 432         if (!ec || !data)
 433                 return -EINVAL;
 434
 435         /*
 436          * Query the EC to find out which _Qxx method we need to evaluate.
 437          * Note that successful completion of the query causes the ACPI_EC_SCI
 438          * bit to be cleared (and thus clearing the interrupt source).
 439          */
 440
 441         result = acpi_ec_transaction(ec, ACPI_EC_COMMAND_QUERY, NULL, 0, &d, 1, 0);
 442         if (result)
 443                 return result;
 444
 445         if (!d)
 446                 return -ENODATA;
 447
 448         *data = d;
 449         return 0;
 450 }
 451
 452 /* --------------------------------------------------------------------------
 453                                 Event Management
 454    -------------------------------------------------------------------------- */
 455 int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
 456                               acpi_handle handle, acpi_ec_query_func func,
 457                               void *data)
 458 {
 459         struct acpi_ec_query_handler *handler =
 460             kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL);
 461         if (!handler)
 462                 return -ENOMEM;
 463
 464         handler->query_bit = query_bit;
 465         handler->handle = handle;
 466         handler->func = func;
 467         handler->data = data;
 468         mutex_lock(&ec->lock);
 469         list_add(&handler->node, &ec->list);
 470         mutex_unlock(&ec->lock);
 471         return 0;
 472 }
 473
 474 EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler);
 475
 476 void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit)
 477 {
 478         struct acpi_ec_query_handler *handler, *tmp;
 479         mutex_lock(&ec->lock);
 480         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
 481                 if (query_bit == handler->query_bit) {
 482                         list_del(&handler->node);
 483                         kfree(handler);
 484                 }
 485         }
 486         mutex_unlock(&ec->lock);
 487 }
 488
 489 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler);
 490
 491 static void acpi_ec_gpe_query(void *ec_cxt)
 492 {
 493         struct acpi_ec *ec = ec_cxt;
 494         u8 value = 0;
 495         struct acpi_ec_query_handler *handler, copy;
 496
 497         if (!ec || acpi_ec_query(ec, &value))
 498                 return;
 499         mutex_lock(&ec->lock);
 500         list_for_each_entry(handler, &ec->list, node) {
 501                 if (value == handler->query_bit) {
 502                         /* have custom handler for this bit */
 503                         memcpy(&copy, handler, sizeof(copy));
 504                         mutex_unlock(&ec->lock);
 505                         if (copy.func) {
 506                                 copy.func(copy.data);
 507                         } else if (copy.handle) {
 508                                 acpi_evaluate_object(copy.handle, NULL, NULL, NULL);
 509                         }
 510                         return;
 511                 }
 512         }
 513         mutex_unlock(&ec->lock);
 514 }
 515
 516 static u32 acpi_ec_gpe_handler(void *data)
 517 {
 518         acpi_status status = AE_OK;
 519         struct acpi_ec *ec = data;
 520
 521         pr_debug(PREFIX "~~~> interrupt\n");
 522         clear_bit(EC_FLAGS_WAIT_GPE, &ec->flags);
 523         if (test_bit(EC_FLAGS_GPE_MODE, &ec->flags))
 524                 wake_up(&ec->wait);
 525
 526         if (acpi_ec_read_status(ec) & ACPI_EC_FLAG_SCI) {
 527                 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags))
 528                         status = acpi_os_execute(OSL_EC_BURST_HANDLER,
 529                                 acpi_ec_gpe_query, ec);
 530         } else if (unlikely(!test_bit(EC_FLAGS_GPE_MODE, &ec->flags))) {
 531                 /* this is non-query, must be confirmation */
 532                 if (printk_ratelimit())
 533                         pr_info(PREFIX "non-query interrupt received,"
 534                                 " switching to interrupt mode\n");
 535                 set_bit(EC_FLAGS_GPE_MODE, &ec->flags);
 536         }
 537
 538         return ACPI_SUCCESS(status) ?
 539             ACPI_INTERRUPT_HANDLED : ACPI_INTERRUPT_NOT_HANDLED;
 540 }
 541
 542 /* --------------------------------------------------------------------------
 543                              Address Space Management
 544    -------------------------------------------------------------------------- */
 545
 546 static acpi_status
 547 acpi_ec_space_setup(acpi_handle region_handle,
 548                     u32 function, void *handler_context, void **return_context)
 549 {
 550         /*
 551          * The EC object is in the handler context and is needed
 552          * when calling the acpi_ec_space_handler.
 553          */
 554         *return_context = (function != ACPI_REGION_DEACTIVATE) ?
 555             handler_context : NULL;
 556
 557         return AE_OK;
 558 }
 559
 560 static acpi_status
 561 acpi_ec_space_handler(u32 function, acpi_physical_address address,
 562                       u32 bits, acpi_integer *value,
 563                       void *handler_context, void *region_context)
 564 {
 565         struct acpi_ec *ec = handler_context;
 566         int result = 0, i = 0;
 567         u8 temp = 0;
 568
 569         if ((address > 0xFF) || !value || !handler_context)
 570                 return AE_BAD_PARAMETER;
 571
 572         if (function != ACPI_READ && function != ACPI_WRITE)
 573                 return AE_BAD_PARAMETER;
 574
 575         if (bits != 8 && acpi_strict)
 576                 return AE_BAD_PARAMETER;
 577
 578         while (bits - i > 0) {
 579                 if (function == ACPI_READ) {
 580                         result = acpi_ec_read(ec, address, &temp);
 581                         (*value) |= ((acpi_integer)temp) << i;
 582                 } else {
 583                         temp = 0xff & ((*value) >> i);
 584                         result = acpi_ec_write(ec, address, temp);
 585                 }
 586                 i += 8;
 587                 ++address;
 588         }
 589
 590         switch (result) {
 591         case -EINVAL:
 592                 return AE_BAD_PARAMETER;
 593                 break;
 594         case -ENODEV:
 595                 return AE_NOT_FOUND;
 596                 break;
 597         case -ETIME:
 598                 return AE_TIME;
 599                 break;
 600         default:
 601                 return AE_OK;
 602         }
 603 }
 604
 605 /* --------------------------------------------------------------------------
 606                               FS Interface (/proc)
 607    -------------------------------------------------------------------------- */
 608
 609 static struct proc_dir_entry *acpi_ec_dir;
 610
 611 static int acpi_ec_read_info(struct seq_file *seq, void *offset)
 612 {
 613         struct acpi_ec *ec = seq->private;
 614
 615         if (!ec)
 616                 goto end;
 617
 618         seq_printf(seq, "gpe:\t\t\t0x%02x\n", (u32) ec->gpe);
 619         seq_printf(seq, "ports:\t\t\t0x%02x, 0x%02x\n",
 620                    (unsigned)ec->command_addr, (unsigned)ec->data_addr);
 621         seq_printf(seq, "use global lock:\t%s\n",
 622                    ec->global_lock ? "yes" : "no");
 623       end:
 624         return 0;
 625 }
 626
 627 static int acpi_ec_info_open_fs(struct inode *inode, struct file *file)
 628 {
 629         return single_open(file, acpi_ec_read_info, PDE(inode)->data);
 630 }
 631
 632 static struct file_operations acpi_ec_info_ops = {
 633         .open = acpi_ec_info_open_fs,
 634         .read = seq_read,
 635         .llseek = seq_lseek,
 636         .release = single_release,
 637         .owner = THIS_MODULE,
 638 };
 639
 640 static int acpi_ec_add_fs(struct acpi_device *device)
 641 {
 642         struct proc_dir_entry *entry = NULL;
 643
 644         if (!acpi_device_dir(device)) {
 645                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
 646                                                      acpi_ec_dir);
 647                 if (!acpi_device_dir(device))
 648                         return -ENODEV;
 649         }
 650
 651         entry = create_proc_entry(ACPI_EC_FILE_INFO, S_IRUGO,
 652                                   acpi_device_dir(device));
 653         if (!entry)
 654                 return -ENODEV;
 655         else {
 656                 entry->proc_fops = &acpi_ec_info_ops;
 657                 entry->data = acpi_driver_data(device);
 658                 entry->owner = THIS_MODULE;
 659         }
 660
 661         return 0;
 662 }
 663
 664 static int acpi_ec_remove_fs(struct acpi_device *device)
 665 {
 666
 667         if (acpi_device_dir(device)) {
 668                 remove_proc_entry(ACPI_EC_FILE_INFO, acpi_device_dir(device));
 669                 remove_proc_entry(acpi_device_bid(device), acpi_ec_dir);
 670                 acpi_device_dir(device) = NULL;
 671         }
 672
 673         return 0;
 674 }
 675
 676 /* --------------------------------------------------------------------------
 677                                Driver Interface
 678    -------------------------------------------------------------------------- */
 679 static acpi_status
 680 ec_parse_io_ports(struct acpi_resource *resource, void *context);
 681
 682 static struct acpi_ec *make_acpi_ec(void)
 683 {
 684         struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
 685         if (!ec)
 686                 return NULL;
 687         ec->flags = 1 << EC_FLAGS_QUERY_PENDING;
 688         mutex_init(&ec->lock);
 689         init_waitqueue_head(&ec->wait);
 690         INIT_LIST_HEAD(&ec->list);
 691         return ec;
 692 }
 693
 694 static acpi_status
 695 acpi_ec_register_query_methods(acpi_handle handle, u32 level,
 696                                void *context, void **return_value)
 697 {
 698         struct acpi_namespace_node *node = handle;
 699         struct acpi_ec *ec = context;
 700         int value = 0;
 701         if (sscanf(node->name.ascii, "_Q%x", &value) == 1) {
 702                 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL);
 703         }
 704         return AE_OK;
 705 }
 706
 707 static acpi_status
 708 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
 709 {
 710         acpi_status status;
 711
 712         struct acpi_ec *ec = context;
 713         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
 714                                      ec_parse_io_ports, ec);
 715         if (ACPI_FAILURE(status))
 716                 return status;
 717
 718         /* Get GPE bit assignment (EC events). */
 719         /* TODO: Add support for _GPE returning a package */
 720         status = acpi_evaluate_integer(handle, "_GPE", NULL, &ec->gpe);
 721         if (ACPI_FAILURE(status))
 722                 return status;
 723         /* Find and register all query methods */
 724         acpi_walk_namespace(ACPI_TYPE_METHOD, handle, 1,
 725                             acpi_ec_register_query_methods, ec, NULL);
 726         /* Use the global lock for all EC transactions? */
 727         acpi_evaluate_integer(handle, "_GLK", NULL, &ec->global_lock);
 728         ec->handle = handle;
 729         return AE_CTRL_TERMINATE;
 730 }
 731
 732 static void ec_remove_handlers(struct acpi_ec *ec)
 733 {
 734         if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle,
 735                                 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler)))
 736                 pr_err(PREFIX "failed to remove space handler\n");
 737         if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe,
 738                                 &acpi_ec_gpe_handler)))
 739                 pr_err(PREFIX "failed to remove gpe handler\n");
 740         ec->handlers_installed = 0;
 741 }
 742
 743 static int acpi_ec_add(struct acpi_device *device)
 744 {
 745         struct acpi_ec *ec = NULL;
 746
 747         if (!device)
 748                 return -EINVAL;
 749         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
 750         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
 751
 752         /* Check for boot EC */
 753         if (boot_ec) {
 754                 if (boot_ec->handle == device->handle) {
 755                         /* Pre-loaded EC from DSDT, just move pointer */
 756                         ec = boot_ec;
 757                         boot_ec = NULL;
 758                         goto end;
 759                 } else if (boot_ec->handle == ACPI_ROOT_OBJECT) {
 760                         /* ECDT-based EC, time to shut it down */
 761                         ec_remove_handlers(boot_ec);
 762                         kfree(boot_ec);
 763                         first_ec = boot_ec = NULL;
 764                 }
 765         }
 766
 767         ec = make_acpi_ec();
 768         if (!ec)
 769                 return -ENOMEM;
 770
 771         if (ec_parse_device(device->handle, 0, ec, NULL) !=
 772             AE_CTRL_TERMINATE) {
 773                 kfree(ec);
 774                 return -EINVAL;
 775         }
 776         ec->handle = device->handle;
 777       end:
 778         if (!first_ec)
 779                 first_ec = ec;
 780         acpi_driver_data(device) = ec;
 781         acpi_ec_add_fs(device);
 782         pr_info(PREFIX "GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n",
 783                           ec->gpe, ec->command_addr, ec->data_addr);
 784         pr_info(PREFIX "driver started in %s mode\n",
 785                 (test_bit(EC_FLAGS_GPE_MODE, &ec->flags))?"interrupt":"poll");
 786         return 0;
 787 }
 788
 789 static int acpi_ec_remove(struct acpi_device *device, int type)
 790 {
 791         struct acpi_ec *ec;
 792         struct acpi_ec_query_handler *handler, *tmp;
 793
 794         if (!device)
 795                 return -EINVAL;
 796
 797         ec = acpi_driver_data(device);
 798         mutex_lock(&ec->lock);
 799         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
 800                 list_del(&handler->node);
 801                 kfree(handler);
 802         }
 803         mutex_unlock(&ec->lock);
 804         acpi_ec_remove_fs(device);
 805         acpi_driver_data(device) = NULL;
 806         if (ec == first_ec)
 807                 first_ec = NULL;
 808         kfree(ec);
 809         return 0;
 810 }
 811
 812 static acpi_status
 813 ec_parse_io_ports(struct acpi_resource *resource, void *context)
 814 {
 815         struct acpi_ec *ec = context;
 816
 817         if (resource->type != ACPI_RESOURCE_TYPE_IO)
 818                 return AE_OK;
 819
 820         /*
 821          * The first address region returned is the data port, and
 822          * the second address region returned is the status/command
 823          * port.
 824          */
 825         if (ec->data_addr == 0)
 826                 ec->data_addr = resource->data.io.minimum;
 827         else if (ec->command_addr == 0)
 828                 ec->command_addr = resource->data.io.minimum;
 829         else
 830                 return AE_CTRL_TERMINATE;
 831
 832         return AE_OK;
 833 }
 834
 835 static int ec_install_handlers(struct acpi_ec *ec)
 836 {
 837         acpi_status status;
 838         if (ec->handlers_installed)
 839                 return 0;
 840         status = acpi_install_gpe_handler(NULL, ec->gpe,
 841                                           ACPI_GPE_EDGE_TRIGGERED,
 842                                           &acpi_ec_gpe_handler, ec);
 843         if (ACPI_FAILURE(status))
 844                 return -ENODEV;
 845
 846         acpi_set_gpe_type(NULL, ec->gpe, ACPI_GPE_TYPE_RUNTIME);
 847         acpi_enable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
 848
 849         status = acpi_install_address_space_handler(ec->handle,
 850                                                     ACPI_ADR_SPACE_EC,
 851                                                     &acpi_ec_space_handler,
 852                                                     &acpi_ec_space_setup, ec);
 853         if (ACPI_FAILURE(status)) {
 854                 acpi_remove_gpe_handler(NULL, ec->gpe, &acpi_ec_gpe_handler);
 855                 return -ENODEV;
 856         }
 857
 858         ec->handlers_installed = 1;
 859         return 0;
 860 }
 861
 862 static int acpi_ec_start(struct acpi_device *device)
 863 {
 864         struct acpi_ec *ec;
 865         int ret = 0;
 866
 867         if (!device)
 868                 return -EINVAL;
 869
 870         ec = acpi_driver_data(device);
 871
 872         if (!ec)
 873                 return -EINVAL;
 874
 875         ret = ec_install_handlers(ec);
 876
 877         /* EC is fully operational, allow queries */
 878         clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
 879         return ret;
 880 }
 881
 882 static int acpi_ec_stop(struct acpi_device *device, int type)
 883 {
 884         struct acpi_ec *ec;
 885         if (!device)
 886                 return -EINVAL;
 887         ec = acpi_driver_data(device);
 888         if (!ec)
 889                 return -EINVAL;
 890         ec_remove_handlers(ec);
 891
 892         return 0;
 893 }
 894
 895 int __init acpi_boot_ec_enable(void)
 896 {
 897         if (!boot_ec || boot_ec->handlers_installed)
 898                 return 0;
 899         if (!ec_install_handlers(boot_ec)) {
 900                 first_ec = boot_ec;
 901                 return 0;
 902         }
 903         return -EFAULT;
 904 }
 905
 906 int __init acpi_ec_ecdt_probe(void)
 907 {
 908         int ret;
 909         acpi_status status;
 910         struct acpi_table_ecdt *ecdt_ptr;
 911
 912         boot_ec = make_acpi_ec();
 913         if (!boot_ec)
 914                 return -ENOMEM;
 915         /*
 916          * Generate a boot ec context
 917          */
 918         status = acpi_get_table(ACPI_SIG_ECDT, 1,
 919                                 (struct acpi_table_header **)&ecdt_ptr);
 920         if (ACPI_SUCCESS(status)) {
 921                 pr_info(PREFIX "EC description table is found, configuring boot EC\n");
 922                 boot_ec->command_addr = ecdt_ptr->control.address;
 923                 boot_ec->data_addr = ecdt_ptr->data.address;
 924                 boot_ec->gpe = ecdt_ptr->gpe;
 925                 boot_ec->handle = ACPI_ROOT_OBJECT;
 926         } else {
 927                 /* This workaround is needed only on some broken machines,
 928                  * which require early EC, but fail to provide ECDT */
 929                 acpi_handle x;
 930                 printk(KERN_DEBUG PREFIX "Look up EC in DSDT\n");
 931                 status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device,
 932                                                 boot_ec, NULL);
 933                 /* Check that acpi_get_devices actually find something */
 934                 if (ACPI_FAILURE(status) || !boot_ec->handle)
 935                         goto error;
 936                 /* We really need to limit this workaround, the only ASUS,
 937                  * which needs it, has fake EC._INI method, so use it as flag.
 938                  * Keep boot_ec struct as it will be needed soon.
 939                  */
 940                 if (ACPI_FAILURE(acpi_get_handle(boot_ec->handle, "_INI", &x)))
 941                         return -ENODEV;
 942         }
 943
 944         ret = ec_install_handlers(boot_ec);
 945         if (!ret) {
 946                 first_ec = boot_ec;
 947                 return 0;
 948         }
 949       error:
 950         kfree(boot_ec);
 951         boot_ec = NULL;
 952         return -ENODEV;
 953 }
 954
 955 static int __init acpi_ec_init(void)
 956 {
 957         int result = 0;
 958
 959         if (acpi_disabled)
 960                 return 0;
 961
 962         acpi_ec_dir = proc_mkdir(ACPI_EC_CLASS, acpi_root_dir);
 963         if (!acpi_ec_dir)
 964                 return -ENODEV;
 965
 966         /* Now register the driver for the EC */
 967         result = acpi_bus_register_driver(&acpi_ec_driver);
 968         if (result < 0) {
 969                 remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
 970                 return -ENODEV;
 971         }
 972
 973         return result;
 974 }
 975
 976 subsys_initcall(acpi_ec_init);
 977
 978 /* EC driver currently not unloadable */
 979 #if 0
 980 static void __exit acpi_ec_exit(void)
 981 {
 982
 983         acpi_bus_unregister_driver(&acpi_ec_driver);
 984
 985         remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
 986
 987         return;
 988 }
 989 #endif  /* 0 */