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 /* Uncomment next line to get verbose print outs*/
  30 /* #define DEBUG */
  31
  32 #include <linux/kernel.h>
  33 #include <linux/module.h>
  34 #include <linux/init.h>
  35 #include <linux/types.h>
  36 #include <linux/delay.h>
  37 #include <linux/proc_fs.h>
  38 #include <linux/seq_file.h>
  39 #include <linux/interrupt.h>
  40 #include <linux/list.h>
  41 #include <asm/io.h>
  42 #include <acpi/acpi_bus.h>
  43 #include <acpi/acpi_drivers.h>
  44 #include <acpi/actypes.h>
  45
  46 #define ACPI_EC_CLASS                   "embedded_controller"
  47 #define ACPI_EC_DEVICE_NAME             "Embedded Controller"
  48 #define ACPI_EC_FILE_INFO               "info"
  49
  50 #undef PREFIX
  51 #define PREFIX                          "ACPI: EC: "
  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 #define ACPI_EC_UDELAY          100     /* Wait 100us before polling EC again */
  77
  78 enum {
  79         EC_FLAGS_WAIT_GPE = 0,          /* Don't check status until GPE arrives */
  80         EC_FLAGS_QUERY_PENDING,         /* Query is pending */
  81         EC_FLAGS_GPE_MODE,              /* Expect GPE to be sent for status change */
  82         EC_FLAGS_NO_GPE,                /* Don't use GPE mode */
  83         EC_FLAGS_RESCHEDULE_POLL        /* Re-schedule poll */
  84 };
  85
  86 /* If we find an EC via the ECDT, we need to keep a ptr to its context */
  87 /* External interfaces use first EC only, so remember */
  88 typedef int (*acpi_ec_query_func) (void *data);
  89
  90 struct acpi_ec_query_handler {
  91         struct list_head node;
  92         acpi_ec_query_func func;
  93         acpi_handle handle;
  94         void *data;
  95         u8 query_bit;
  96 };
  97
  98 static struct acpi_ec {
  99         acpi_handle handle;
 100         unsigned long gpe;
 101         unsigned long command_addr;
 102         unsigned long data_addr;
 103         unsigned long global_lock;
 104         unsigned long flags;
 105         struct mutex lock;
 106         wait_queue_head_t wait;
 107         struct list_head list;
 108         struct delayed_work work;
 109         atomic_t irq_count;
 110         u8 handlers_installed;
 111 } *boot_ec, *first_ec;
 112
 113 /*
 114  * Some Asus system have exchanged ECDT data/command IO addresses.
 115  */
 116 static int print_ecdt_error(const struct dmi_system_id *id)
 117 {
 118         printk(KERN_NOTICE PREFIX "%s detected - "
 119                 "ECDT has exchanged control/data I/O address\n",
 120                 id->ident);
 121         return 0;
 122 }
 123
 124 static struct dmi_system_id __cpuinitdata ec_dmi_table[] = {
 125         {
 126         print_ecdt_error, "Asus L4R", {
 127         DMI_MATCH(DMI_BIOS_VERSION, "1008.006"),
 128         DMI_MATCH(DMI_PRODUCT_NAME, "L4R"),
 129         DMI_MATCH(DMI_BOARD_NAME, "L4R") }, NULL},
 130         {
 131         print_ecdt_error, "Asus M6R", {
 132         DMI_MATCH(DMI_BIOS_VERSION, "0207"),
 133         DMI_MATCH(DMI_PRODUCT_NAME, "M6R"),
 134         DMI_MATCH(DMI_BOARD_NAME, "M6R") }, NULL},
 135         {},
 136 };
 137
 138 /* --------------------------------------------------------------------------
 139                              Transaction Management
 140    -------------------------------------------------------------------------- */
 141
 142 static inline u8 acpi_ec_read_status(struct acpi_ec *ec)
 143 {
 144         u8 x = inb(ec->command_addr);
 145         pr_debug(PREFIX "---> status = 0x%2.2x\n", x);
 146         return x;
 147 }
 148
 149 static inline u8 acpi_ec_read_data(struct acpi_ec *ec)
 150 {
 151         u8 x = inb(ec->data_addr);
 152         pr_debug(PREFIX "---> data = 0x%2.2x\n", x);
 153         return inb(ec->data_addr);
 154 }
 155
 156 static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command)
 157 {
 158         pr_debug(PREFIX "<--- command = 0x%2.2x\n", command);
 159         outb(command, ec->command_addr);
 160 }
 161
 162 static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data)
 163 {
 164         pr_debug(PREFIX "<--- data = 0x%2.2x\n", data);
 165         outb(data, ec->data_addr);
 166 }
 167
 168 static inline int acpi_ec_check_status(struct acpi_ec *ec, enum ec_event event)
 169 {
 170         if (test_bit(EC_FLAGS_WAIT_GPE, &ec->flags))
 171                 return 0;
 172         if (event == ACPI_EC_EVENT_OBF_1) {
 173                 if (acpi_ec_read_status(ec) & ACPI_EC_FLAG_OBF)
 174                         return 1;
 175         } else if (event == ACPI_EC_EVENT_IBF_0) {
 176                 if (!(acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF))
 177                         return 1;
 178         }
 179
 180         return 0;
 181 }
 182
 183 static void ec_schedule_ec_poll(struct acpi_ec *ec)
 184 {
 185         if (test_bit(EC_FLAGS_RESCHEDULE_POLL, &ec->flags))
 186                 schedule_delayed_work(&ec->work,
 187                                       msecs_to_jiffies(ACPI_EC_DELAY));
 188 }
 189
 190 static void ec_switch_to_poll_mode(struct acpi_ec *ec)
 191 {
 192         set_bit(EC_FLAGS_NO_GPE, &ec->flags);
 193         clear_bit(EC_FLAGS_GPE_MODE, &ec->flags);
 194         acpi_disable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
 195         set_bit(EC_FLAGS_RESCHEDULE_POLL, &ec->flags);
 196 }
 197
 198 static int acpi_ec_wait(struct acpi_ec *ec, enum ec_event event, int force_poll)
 199 {
 200         atomic_set(&ec->irq_count, 0);
 201         if (likely(test_bit(EC_FLAGS_GPE_MODE, &ec->flags)) &&
 202             likely(!force_poll)) {
 203                 if (wait_event_timeout(ec->wait, acpi_ec_check_status(ec, event),
 204                                        msecs_to_jiffies(ACPI_EC_DELAY)))
 205                         return 0;
 206                 clear_bit(EC_FLAGS_WAIT_GPE, &ec->flags);
 207                 if (acpi_ec_check_status(ec, event)) {
 208                         /* missing GPEs, switch back to poll mode */
 209                         if (printk_ratelimit())
 210                                 pr_info(PREFIX "missing confirmations, "
 211                                                 "switch off interrupt mode.\n");
 212                         ec_switch_to_poll_mode(ec);
 213                         ec_schedule_ec_poll(ec);
 214                         return 0;
 215                 }
 216         } else {
 217                 unsigned long delay = jiffies + msecs_to_jiffies(ACPI_EC_DELAY);
 218                 clear_bit(EC_FLAGS_WAIT_GPE, &ec->flags);
 219                 while (time_before(jiffies, delay)) {
 220                         if (acpi_ec_check_status(ec, event))
 221                                 return 0;
 222                         msleep(1);
 223                 }
 224                 if (acpi_ec_check_status(ec,event))
 225                         return 0;
 226         }
 227         pr_err(PREFIX "acpi_ec_wait timeout, status = 0x%2.2x, event = %s\n",
 228                 acpi_ec_read_status(ec),
 229                 (event == ACPI_EC_EVENT_OBF_1) ? "\"b0=1\"" : "\"b1=0\"");
 230         return -ETIME;
 231 }
 232
 233 static int acpi_ec_transaction_unlocked(struct acpi_ec *ec, u8 command,
 234                                         const u8 * wdata, unsigned wdata_len,
 235                                         u8 * rdata, unsigned rdata_len,
 236                                         int force_poll)
 237 {
 238         int result = 0;
 239         set_bit(EC_FLAGS_WAIT_GPE, &ec->flags);
 240         pr_debug(PREFIX "transaction start\n");
 241         acpi_ec_write_cmd(ec, command);
 242         for (; wdata_len > 0; --wdata_len) {
 243                 result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0, force_poll);
 244                 if (result) {
 245                         pr_err(PREFIX
 246                                "write_cmd timeout, command = %d\n", command);
 247                         goto end;
 248                 }
 249                 set_bit(EC_FLAGS_WAIT_GPE, &ec->flags);
 250                 acpi_ec_write_data(ec, *(wdata++));
 251         }
 252
 253         if (!rdata_len) {
 254                 result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0, force_poll);
 255                 if (result) {
 256                         pr_err(PREFIX
 257                                "finish-write timeout, command = %d\n", command);
 258                         goto end;
 259                 }
 260         } else if (command == ACPI_EC_COMMAND_QUERY)
 261                 clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
 262
 263         for (; rdata_len > 0; --rdata_len) {
 264                 result = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF_1, force_poll);
 265                 if (result) {
 266                         pr_err(PREFIX "read timeout, command = %d\n", command);
 267                         goto end;
 268                 }
 269                 /* Don't expect GPE after last read */
 270                 if (rdata_len > 1)
 271                         set_bit(EC_FLAGS_WAIT_GPE, &ec->flags);
 272                 *(rdata++) = acpi_ec_read_data(ec);
 273         }
 274       end:
 275         pr_debug(PREFIX "transaction end\n");
 276         return result;
 277 }
 278
 279 static int acpi_ec_transaction(struct acpi_ec *ec, u8 command,
 280                                const u8 * wdata, unsigned wdata_len,
 281                                u8 * rdata, unsigned rdata_len,
 282                                int force_poll)
 283 {
 284         int status;
 285         u32 glk;
 286
 287         if (!ec || (wdata_len && !wdata) || (rdata_len && !rdata))
 288                 return -EINVAL;
 289
 290         if (rdata)
 291                 memset(rdata, 0, rdata_len);
 292
 293         mutex_lock(&ec->lock);
 294         if (ec->global_lock) {
 295                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 296                 if (ACPI_FAILURE(status)) {
 297                         mutex_unlock(&ec->lock);
 298                         return -ENODEV;
 299                 }
 300         }
 301
 302         status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0, 0);
 303         if (status) {
 304                 pr_err(PREFIX "input buffer is not empty, "
 305                                 "aborting transaction\n");
 306                 goto end;
 307         }
 308
 309         status = acpi_ec_transaction_unlocked(ec, command,
 310                                               wdata, wdata_len,
 311                                               rdata, rdata_len,
 312                                               force_poll);
 313
 314       end:
 315
 316         if (ec->global_lock)
 317                 acpi_release_global_lock(glk);
 318         mutex_unlock(&ec->lock);
 319
 320         return status;
 321 }
 322
 323 /*
 324  * Note: samsung nv5000 doesn't work with ec burst mode.
 325  * http://bugzilla.kernel.org/show_bug.cgi?id=4980
 326  */
 327 int acpi_ec_burst_enable(struct acpi_ec *ec)
 328 {
 329         u8 d;
 330         return acpi_ec_transaction(ec, ACPI_EC_BURST_ENABLE, NULL, 0, &d, 1, 0);
 331 }
 332
 333 int acpi_ec_burst_disable(struct acpi_ec *ec)
 334 {
 335         return acpi_ec_transaction(ec, ACPI_EC_BURST_DISABLE, NULL, 0, NULL, 0, 0);
 336 }
 337
 338 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 * data)
 339 {
 340         int result;
 341         u8 d;
 342
 343         result = acpi_ec_transaction(ec, ACPI_EC_COMMAND_READ,
 344                                      &address, 1, &d, 1, 0);
 345         *data = d;
 346         return result;
 347 }
 348
 349 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
 350 {
 351         u8 wdata[2] = { address, data };
 352         return acpi_ec_transaction(ec, ACPI_EC_COMMAND_WRITE,
 353                                    wdata, 2, NULL, 0, 0);
 354 }
 355
 356 /*
 357  * Externally callable EC access functions. For now, assume 1 EC only
 358  */
 359 int ec_burst_enable(void)
 360 {
 361         if (!first_ec)
 362                 return -ENODEV;
 363         return acpi_ec_burst_enable(first_ec);
 364 }
 365
 366 EXPORT_SYMBOL(ec_burst_enable);
 367
 368 int ec_burst_disable(void)
 369 {
 370         if (!first_ec)
 371                 return -ENODEV;
 372         return acpi_ec_burst_disable(first_ec);
 373 }
 374
 375 EXPORT_SYMBOL(ec_burst_disable);
 376
 377 int ec_read(u8 addr, u8 * val)
 378 {
 379         int err;
 380         u8 temp_data;
 381
 382         if (!first_ec)
 383                 return -ENODEV;
 384
 385         err = acpi_ec_read(first_ec, addr, &temp_data);
 386
 387         if (!err) {
 388                 *val = temp_data;
 389                 return 0;
 390         } else
 391                 return err;
 392 }
 393
 394 EXPORT_SYMBOL(ec_read);
 395
 396 int ec_write(u8 addr, u8 val)
 397 {
 398         int err;
 399
 400         if (!first_ec)
 401                 return -ENODEV;
 402
 403         err = acpi_ec_write(first_ec, addr, val);
 404
 405         return err;
 406 }
 407
 408 EXPORT_SYMBOL(ec_write);
 409
 410 int ec_transaction(u8 command,
 411                    const u8 * wdata, unsigned wdata_len,
 412                    u8 * rdata, unsigned rdata_len,
 413                    int force_poll)
 414 {
 415         if (!first_ec)
 416                 return -ENODEV;
 417
 418         return acpi_ec_transaction(first_ec, command, wdata,
 419                                    wdata_len, rdata, rdata_len,
 420                                    force_poll);
 421 }
 422
 423 EXPORT_SYMBOL(ec_transaction);
 424
 425 static int acpi_ec_query(struct acpi_ec *ec, u8 * data)
 426 {
 427         int result;
 428         u8 d;
 429
 430         if (!ec || !data)
 431                 return -EINVAL;
 432
 433         /*
 434          * Query the EC to find out which _Qxx method we need to evaluate.
 435          * Note that successful completion of the query causes the ACPI_EC_SCI
 436          * bit to be cleared (and thus clearing the interrupt source).
 437          */
 438
 439         result = acpi_ec_transaction(ec, ACPI_EC_COMMAND_QUERY, NULL, 0, &d, 1, 0);
 440         if (result)
 441                 return result;
 442
 443         if (!d)
 444                 return -ENODATA;
 445
 446         *data = d;
 447         return 0;
 448 }
 449
 450 /* --------------------------------------------------------------------------
 451                                 Event Management
 452    -------------------------------------------------------------------------- */
 453 int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
 454                               acpi_handle handle, acpi_ec_query_func func,
 455                               void *data)
 456 {
 457         struct acpi_ec_query_handler *handler =
 458             kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL);
 459         if (!handler)
 460                 return -ENOMEM;
 461
 462         handler->query_bit = query_bit;
 463         handler->handle = handle;
 464         handler->func = func;
 465         handler->data = data;
 466         mutex_lock(&ec->lock);
 467         list_add(&handler->node, &ec->list);
 468         mutex_unlock(&ec->lock);
 469         return 0;
 470 }
 471
 472 EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler);
 473
 474 void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit)
 475 {
 476         struct acpi_ec_query_handler *handler, *tmp;
 477         mutex_lock(&ec->lock);
 478         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
 479                 if (query_bit == handler->query_bit) {
 480                         list_del(&handler->node);
 481                         kfree(handler);
 482                 }
 483         }
 484         mutex_unlock(&ec->lock);
 485 }
 486
 487 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler);
 488
 489 static void acpi_ec_gpe_query(void *ec_cxt)
 490 {
 491         struct acpi_ec *ec = ec_cxt;
 492         u8 value = 0;
 493         struct acpi_ec_query_handler *handler, copy;
 494
 495         if (!ec || acpi_ec_query(ec, &value))
 496                 return;
 497         mutex_lock(&ec->lock);
 498         list_for_each_entry(handler, &ec->list, node) {
 499                 if (value == handler->query_bit) {
 500                         /* have custom handler for this bit */
 501                         memcpy(&copy, handler, sizeof(copy));
 502                         mutex_unlock(&ec->lock);
 503                         if (copy.func) {
 504                                 copy.func(copy.data);
 505                         } else if (copy.handle) {
 506                                 acpi_evaluate_object(copy.handle, NULL, NULL, NULL);
 507                         }
 508                         return;
 509                 }
 510         }
 511         mutex_unlock(&ec->lock);
 512 }
 513
 514 static u32 acpi_ec_gpe_handler(void *data)
 515 {
 516         acpi_status status = AE_OK;
 517         struct acpi_ec *ec = data;
 518         u8 state = acpi_ec_read_status(ec);
 519
 520         pr_debug(PREFIX "~~~> interrupt\n");
 521         atomic_inc(&ec->irq_count);
 522         if (atomic_read(&ec->irq_count) > 5) {
 523                 pr_err(PREFIX "GPE storm detected, disabling EC GPE\n");
 524                 ec_switch_to_poll_mode(ec);
 525                 goto end;
 526         }
 527         clear_bit(EC_FLAGS_WAIT_GPE, &ec->flags);
 528         if (test_bit(EC_FLAGS_GPE_MODE, &ec->flags))
 529                 wake_up(&ec->wait);
 530
 531         if (state & ACPI_EC_FLAG_SCI) {
 532                 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags))
 533                         status = acpi_os_execute(OSL_EC_BURST_HANDLER,
 534                                 acpi_ec_gpe_query, ec);
 535         } else if (!test_bit(EC_FLAGS_GPE_MODE, &ec->flags) &&
 536                    !test_bit(EC_FLAGS_NO_GPE, &ec->flags) &&
 537                    in_interrupt()) {
 538                 /* this is non-query, must be confirmation */
 539                 if (printk_ratelimit())
 540                         pr_info(PREFIX "non-query interrupt received,"
 541                                 " switching to interrupt mode\n");
 542                 set_bit(EC_FLAGS_GPE_MODE, &ec->flags);
 543                 clear_bit(EC_FLAGS_RESCHEDULE_POLL, &ec->flags);
 544         }
 545 end:
 546         ec_schedule_ec_poll(ec);
 547         return ACPI_SUCCESS(status) ?
 548             ACPI_INTERRUPT_HANDLED : ACPI_INTERRUPT_NOT_HANDLED;
 549 }
 550
 551 static void do_ec_poll(struct work_struct *work)
 552 {
 553         struct acpi_ec *ec = container_of(work, struct acpi_ec, work.work);
 554         atomic_set(&ec->irq_count, 0);
 555         (void)acpi_ec_gpe_handler(ec);
 556 }
 557
 558 /* --------------------------------------------------------------------------
 559                              Address Space Management
 560    -------------------------------------------------------------------------- */
 561
 562 static acpi_status
 563 acpi_ec_space_handler(u32 function, acpi_physical_address address,
 564                       u32 bits, acpi_integer *value,
 565                       void *handler_context, void *region_context)
 566 {
 567         struct acpi_ec *ec = handler_context;
 568         int result = 0, i;
 569         u8 temp = 0;
 570
 571         if ((address > 0xFF) || !value || !handler_context)
 572                 return AE_BAD_PARAMETER;
 573
 574         if (function != ACPI_READ && function != ACPI_WRITE)
 575                 return AE_BAD_PARAMETER;
 576
 577         if (bits != 8 && acpi_strict)
 578                 return AE_BAD_PARAMETER;
 579
 580         acpi_ec_burst_enable(ec);
 581
 582         if (function == ACPI_READ) {
 583                 result = acpi_ec_read(ec, address, &temp);
 584                 *value = temp;
 585         } else {
 586                 temp = 0xff & (*value);
 587                 result = acpi_ec_write(ec, address, temp);
 588         }
 589
 590         for (i = 8; unlikely(bits - i > 0); i += 8) {
 591                 ++address;
 592                 if (function == ACPI_READ) {
 593                         result = acpi_ec_read(ec, address, &temp);
 594                         (*value) |= ((acpi_integer)temp) << i;
 595                 } else {
 596                         temp = 0xff & ((*value) >> i);
 597                         result = acpi_ec_write(ec, address, temp);
 598                 }
 599         }
 600
 601         acpi_ec_burst_disable(ec);
 602
 603         switch (result) {
 604         case -EINVAL:
 605                 return AE_BAD_PARAMETER;
 606                 break;
 607         case -ENODEV:
 608                 return AE_NOT_FOUND;
 609                 break;
 610         case -ETIME:
 611                 return AE_TIME;
 612                 break;
 613         default:
 614                 return AE_OK;
 615         }
 616 }
 617
 618 /* --------------------------------------------------------------------------
 619                               FS Interface (/proc)
 620    -------------------------------------------------------------------------- */
 621
 622 static struct proc_dir_entry *acpi_ec_dir;
 623
 624 static int acpi_ec_read_info(struct seq_file *seq, void *offset)
 625 {
 626         struct acpi_ec *ec = seq->private;
 627
 628         if (!ec)
 629                 goto end;
 630
 631         seq_printf(seq, "gpe:\t\t\t0x%02x\n", (u32) ec->gpe);
 632         seq_printf(seq, "ports:\t\t\t0x%02x, 0x%02x\n",
 633                    (unsigned)ec->command_addr, (unsigned)ec->data_addr);
 634         seq_printf(seq, "use global lock:\t%s\n",
 635                    ec->global_lock ? "yes" : "no");
 636       end:
 637         return 0;
 638 }
 639
 640 static int acpi_ec_info_open_fs(struct inode *inode, struct file *file)
 641 {
 642         return single_open(file, acpi_ec_read_info, PDE(inode)->data);
 643 }
 644
 645 static struct file_operations acpi_ec_info_ops = {
 646         .open = acpi_ec_info_open_fs,
 647         .read = seq_read,
 648         .llseek = seq_lseek,
 649         .release = single_release,
 650         .owner = THIS_MODULE,
 651 };
 652
 653 static int acpi_ec_add_fs(struct acpi_device *device)
 654 {
 655         struct proc_dir_entry *entry = NULL;
 656
 657         if (!acpi_device_dir(device)) {
 658                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
 659                                                      acpi_ec_dir);
 660                 if (!acpi_device_dir(device))
 661                         return -ENODEV;
 662         }
 663
 664         entry = proc_create_data(ACPI_EC_FILE_INFO, S_IRUGO,
 665                                  acpi_device_dir(device),
 666                                  &acpi_ec_info_ops, acpi_driver_data(device));
 667         if (!entry)
 668                 return -ENODEV;
 669         return 0;
 670 }
 671
 672 static int acpi_ec_remove_fs(struct acpi_device *device)
 673 {
 674
 675         if (acpi_device_dir(device)) {
 676                 remove_proc_entry(ACPI_EC_FILE_INFO, acpi_device_dir(device));
 677                 remove_proc_entry(acpi_device_bid(device), acpi_ec_dir);
 678                 acpi_device_dir(device) = NULL;
 679         }
 680
 681         return 0;
 682 }
 683
 684 /* --------------------------------------------------------------------------
 685                                Driver Interface
 686    -------------------------------------------------------------------------- */
 687 static acpi_status
 688 ec_parse_io_ports(struct acpi_resource *resource, void *context);
 689
 690 static struct acpi_ec *make_acpi_ec(void)
 691 {
 692         struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
 693         if (!ec)
 694                 return NULL;
 695         ec->flags = 1 << EC_FLAGS_QUERY_PENDING;
 696         mutex_init(&ec->lock);
 697         init_waitqueue_head(&ec->wait);
 698         INIT_LIST_HEAD(&ec->list);
 699         INIT_DELAYED_WORK_DEFERRABLE(&ec->work, do_ec_poll);
 700         atomic_set(&ec->irq_count, 0);
 701         return ec;
 702 }
 703
 704 static acpi_status
 705 acpi_ec_register_query_methods(acpi_handle handle, u32 level,
 706                                void *context, void **return_value)
 707 {
 708         struct acpi_namespace_node *node = handle;
 709         struct acpi_ec *ec = context;
 710         int value = 0;
 711         if (sscanf(node->name.ascii, "_Q%x", &value) == 1) {
 712                 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL);
 713         }
 714         return AE_OK;
 715 }
 716
 717 static acpi_status
 718 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
 719 {
 720         acpi_status status;
 721         unsigned long long tmp;
 722
 723         struct acpi_ec *ec = context;
 724         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
 725                                      ec_parse_io_ports, ec);
 726         if (ACPI_FAILURE(status))
 727                 return status;
 728
 729         /* Get GPE bit assignment (EC events). */
 730         /* TODO: Add support for _GPE returning a package */
 731         status = acpi_evaluate_integer(handle, "_GPE", NULL, &tmp);
 732         if (ACPI_FAILURE(status))
 733                 return status;
 734         ec->gpe = tmp;
 735         /* Use the global lock for all EC transactions? */
 736         acpi_evaluate_integer(handle, "_GLK", NULL, &tmp);
 737         ec->global_lock = tmp;
 738         ec->handle = handle;
 739         return AE_CTRL_TERMINATE;
 740 }
 741
 742 static void ec_poll_stop(struct acpi_ec *ec)
 743 {
 744         clear_bit(EC_FLAGS_RESCHEDULE_POLL, &ec->flags);
 745         cancel_delayed_work(&ec->work);
 746 }
 747
 748 static void ec_remove_handlers(struct acpi_ec *ec)
 749 {
 750         ec_poll_stop(ec);
 751         if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle,
 752                                 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler)))
 753                 pr_err(PREFIX "failed to remove space handler\n");
 754         if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe,
 755                                 &acpi_ec_gpe_handler)))
 756                 pr_err(PREFIX "failed to remove gpe handler\n");
 757         ec->handlers_installed = 0;
 758 }
 759
 760 static int acpi_ec_add(struct acpi_device *device)
 761 {
 762         struct acpi_ec *ec = NULL;
 763
 764         if (!device)
 765                 return -EINVAL;
 766         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
 767         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
 768
 769         /* Check for boot EC */
 770         if (boot_ec &&
 771             (boot_ec->handle == device->handle ||
 772              boot_ec->handle == ACPI_ROOT_OBJECT)) {
 773                 ec = boot_ec;
 774                 boot_ec = NULL;
 775         } else {
 776                 ec = make_acpi_ec();
 777                 if (!ec)
 778                         return -ENOMEM;
 779                 if (ec_parse_device(device->handle, 0, ec, NULL) !=
 780                     AE_CTRL_TERMINATE) {
 781                         kfree(ec);
 782                         return -EINVAL;
 783                 }
 784         }
 785
 786         ec->handle = device->handle;
 787
 788         /* Find and register all query methods */
 789         acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1,
 790                             acpi_ec_register_query_methods, ec, NULL);
 791
 792         if (!first_ec)
 793                 first_ec = ec;
 794         acpi_driver_data(device) = ec;
 795         acpi_ec_add_fs(device);
 796         pr_info(PREFIX "GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n",
 797                           ec->gpe, ec->command_addr, ec->data_addr);
 798         pr_info(PREFIX "driver started in %s mode\n",
 799                 (test_bit(EC_FLAGS_GPE_MODE, &ec->flags))?"interrupt":"poll");
 800         return 0;
 801 }
 802
 803 static int acpi_ec_remove(struct acpi_device *device, int type)
 804 {
 805         struct acpi_ec *ec;
 806         struct acpi_ec_query_handler *handler, *tmp;
 807
 808         if (!device)
 809                 return -EINVAL;
 810
 811         ec = acpi_driver_data(device);
 812         mutex_lock(&ec->lock);
 813         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
 814                 list_del(&handler->node);
 815                 kfree(handler);
 816         }
 817         mutex_unlock(&ec->lock);
 818         acpi_ec_remove_fs(device);
 819         acpi_driver_data(device) = NULL;
 820         if (ec == first_ec)
 821                 first_ec = NULL;
 822         kfree(ec);
 823         return 0;
 824 }
 825
 826 static acpi_status
 827 ec_parse_io_ports(struct acpi_resource *resource, void *context)
 828 {
 829         struct acpi_ec *ec = context;
 830
 831         if (resource->type != ACPI_RESOURCE_TYPE_IO)
 832                 return AE_OK;
 833
 834         /*
 835          * The first address region returned is the data port, and
 836          * the second address region returned is the status/command
 837          * port.
 838          */
 839         if (ec->data_addr == 0)
 840                 ec->data_addr = resource->data.io.minimum;
 841         else if (ec->command_addr == 0)
 842                 ec->command_addr = resource->data.io.minimum;
 843         else
 844                 return AE_CTRL_TERMINATE;
 845
 846         return AE_OK;
 847 }
 848
 849 static int ec_install_handlers(struct acpi_ec *ec)
 850 {
 851         acpi_status status;
 852         if (ec->handlers_installed)
 853                 return 0;
 854         status = acpi_install_gpe_handler(NULL, ec->gpe,
 855                                           ACPI_GPE_EDGE_TRIGGERED,
 856                                           &acpi_ec_gpe_handler, ec);
 857         if (ACPI_FAILURE(status))
 858                 return -ENODEV;
 859
 860         acpi_set_gpe_type(NULL, ec->gpe, ACPI_GPE_TYPE_RUNTIME);
 861         acpi_enable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
 862
 863         status = acpi_install_address_space_handler(ec->handle,
 864                                                     ACPI_ADR_SPACE_EC,
 865                                                     &acpi_ec_space_handler,
 866                                                     NULL, ec);
 867         if (ACPI_FAILURE(status)) {
 868                 acpi_remove_gpe_handler(NULL, ec->gpe, &acpi_ec_gpe_handler);
 869                 return -ENODEV;
 870         }
 871
 872         ec->handlers_installed = 1;
 873         return 0;
 874 }
 875
 876 static int acpi_ec_start(struct acpi_device *device)
 877 {
 878         struct acpi_ec *ec;
 879         int ret = 0;
 880
 881         if (!device)
 882                 return -EINVAL;
 883
 884         ec = acpi_driver_data(device);
 885
 886         if (!ec)
 887                 return -EINVAL;
 888
 889         ret = ec_install_handlers(ec);
 890
 891         /* EC is fully operational, allow queries */
 892         clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
 893         ec_schedule_ec_poll(ec);
 894         return ret;
 895 }
 896
 897 static int acpi_ec_stop(struct acpi_device *device, int type)
 898 {
 899         struct acpi_ec *ec;
 900         if (!device)
 901                 return -EINVAL;
 902         ec = acpi_driver_data(device);
 903         if (!ec)
 904                 return -EINVAL;
 905         ec_remove_handlers(ec);
 906
 907         return 0;
 908 }
 909
 910 int __init acpi_boot_ec_enable(void)
 911 {
 912         if (!boot_ec || boot_ec->handlers_installed)
 913                 return 0;
 914         if (!ec_install_handlers(boot_ec)) {
 915                 first_ec = boot_ec;
 916                 return 0;
 917         }
 918         return -EFAULT;
 919 }
 920
 921 static const struct acpi_device_id ec_device_ids[] = {
 922         {"PNP0C09", 0},
 923         {"", 0},
 924 };
 925
 926 int __init acpi_ec_ecdt_probe(void)
 927 {
 928         int ret;
 929         acpi_status status;
 930         struct acpi_table_ecdt *ecdt_ptr;
 931
 932         boot_ec = make_acpi_ec();
 933         if (!boot_ec)
 934                 return -ENOMEM;
 935         /*
 936          * Generate a boot ec context
 937          */
 938         status = acpi_get_table(ACPI_SIG_ECDT, 1,
 939                                 (struct acpi_table_header **)&ecdt_ptr);
 940         if (ACPI_SUCCESS(status)) {
 941                 pr_info(PREFIX "EC description table is found, configuring boot EC\n");
 942                 boot_ec->command_addr = ecdt_ptr->control.address;
 943                 boot_ec->data_addr = ecdt_ptr->data.address;
 944                 if (dmi_check_system(ec_dmi_table)) {
 945                         /*
 946                          * If the board falls into ec_dmi_table, it means
 947                          * that ECDT table gives the incorrect command/status
 948                          * & data I/O address. Just fix it.
 949                          */
 950                         boot_ec->data_addr = ecdt_ptr->control.address;
 951                         boot_ec->command_addr = ecdt_ptr->data.address;
 952                 }
 953                 boot_ec->gpe = ecdt_ptr->gpe;
 954                 boot_ec->handle = ACPI_ROOT_OBJECT;
 955                 acpi_get_handle(ACPI_ROOT_OBJECT, ecdt_ptr->id, &boot_ec->handle);
 956         } else {
 957                 /* This workaround is needed only on some broken machines,
 958                  * which require early EC, but fail to provide ECDT */
 959                 acpi_handle x;
 960                 printk(KERN_DEBUG PREFIX "Look up EC in DSDT\n");
 961                 status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device,
 962                                                 boot_ec, NULL);
 963                 /* Check that acpi_get_devices actually find something */
 964                 if (ACPI_FAILURE(status) || !boot_ec->handle)
 965                         goto error;
 966                 /* We really need to limit this workaround, the only ASUS,
 967                  * which needs it, has fake EC._INI method, so use it as flag.
 968                  * Keep boot_ec struct as it will be needed soon.
 969                  */
 970                 if (ACPI_FAILURE(acpi_get_handle(boot_ec->handle, "_INI", &x)))
 971                         return -ENODEV;
 972         }
 973
 974         ret = ec_install_handlers(boot_ec);
 975         if (!ret) {
 976                 first_ec = boot_ec;
 977                 return 0;
 978         }
 979       error:
 980         kfree(boot_ec);
 981         boot_ec = NULL;
 982         return -ENODEV;
 983 }
 984
 985 static int acpi_ec_suspend(struct acpi_device *device, pm_message_t state)
 986 {
 987         struct acpi_ec *ec = acpi_driver_data(device);
 988         /* Stop using GPE */
 989         set_bit(EC_FLAGS_NO_GPE, &ec->flags);
 990         clear_bit(EC_FLAGS_GPE_MODE, &ec->flags);
 991         acpi_disable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
 992         return 0;
 993 }
 994
 995 static int acpi_ec_resume(struct acpi_device *device)
 996 {
 997         struct acpi_ec *ec = acpi_driver_data(device);
 998         /* Enable use of GPE back */
 999         clear_bit(EC_FLAGS_NO_GPE, &ec->flags);
1000         acpi_enable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
1001         return 0;
1002 }
1003
1004 static struct acpi_driver acpi_ec_driver = {
1005         .name = "ec",
1006         .class = ACPI_EC_CLASS,
1007         .ids = ec_device_ids,
1008         .ops = {
1009                 .add = acpi_ec_add,
1010                 .remove = acpi_ec_remove,
1011                 .start = acpi_ec_start,
1012                 .stop = acpi_ec_stop,
1013                 .suspend = acpi_ec_suspend,
1014                 .resume = acpi_ec_resume,
1015                 },
1016 };
1017
1018 static int __init acpi_ec_init(void)
1019 {
1020         int result = 0;
1021
1022         if (acpi_disabled)
1023                 return 0;
1024
1025         acpi_ec_dir = proc_mkdir(ACPI_EC_CLASS, acpi_root_dir);
1026         if (!acpi_ec_dir)
1027                 return -ENODEV;
1028
1029         /* Now register the driver for the EC */
1030         result = acpi_bus_register_driver(&acpi_ec_driver);
1031         if (result < 0) {
1032                 remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1033                 return -ENODEV;
1034         }
1035
1036         return result;
1037 }
1038
1039 subsys_initcall(acpi_ec_init);
1040
1041 /* EC driver currently not unloadable */
1042 #if 0
1043 static void __exit acpi_ec_exit(void)
1044 {
1045
1046         acpi_bus_unregister_driver(&acpi_ec_driver);
1047
1048         remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1049
1050         return;
1051 }
1052 #endif  /* 0 */