git.oblomov.eu Git - linux-2.6/blob - 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;
 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         if (function == ACPI_READ) {
 579                 result = acpi_ec_read(ec, address, &temp);
 580                 *value = temp;
 581         } else {
 582                 temp = 0xff & (*value);
 583                 result = acpi_ec_write(ec, address, temp);
 584         }
 585
 586         for (i = 8; unlikely(bits - i > 0); i += 8) {
 587                 ++address;
 588                 if (function == ACPI_READ) {
 589                         result = acpi_ec_read(ec, address, &temp);
 590                         (*value) |= ((acpi_integer)temp) << i;
 591                 } else {
 592                         temp = 0xff & ((*value) >> i);
 593                         result = acpi_ec_write(ec, address, temp);
 594                 }
 595         }
 596
 597         switch (result) {
 598         case -EINVAL:
 599                 return AE_BAD_PARAMETER;
 600                 break;
 601         case -ENODEV:
 602                 return AE_NOT_FOUND;
 603                 break;
 604         case -ETIME:
 605                 return AE_TIME;
 606                 break;
 607         default:
 608                 return AE_OK;
 609         }
 610 }
 611
 612 /* --------------------------------------------------------------------------
 613                               FS Interface (/proc)
 614    -------------------------------------------------------------------------- */
 615
 616 static struct proc_dir_entry *acpi_ec_dir;
 617
 618 static int acpi_ec_read_info(struct seq_file *seq, void *offset)
 619 {
 620         struct acpi_ec *ec = seq->private;
 621
 622         if (!ec)
 623                 goto end;
 624
 625         seq_printf(seq, "gpe:\t\t\t0x%02x\n", (u32) ec->gpe);
 626         seq_printf(seq, "ports:\t\t\t0x%02x, 0x%02x\n",
 627                    (unsigned)ec->command_addr, (unsigned)ec->data_addr);
 628         seq_printf(seq, "use global lock:\t%s\n",
 629                    ec->global_lock ? "yes" : "no");
 630       end:
 631         return 0;
 632 }
 633
 634 static int acpi_ec_info_open_fs(struct inode *inode, struct file *file)
 635 {
 636         return single_open(file, acpi_ec_read_info, PDE(inode)->data);
 637 }
 638
 639 static struct file_operations acpi_ec_info_ops = {
 640         .open = acpi_ec_info_open_fs,
 641         .read = seq_read,
 642         .llseek = seq_lseek,
 643         .release = single_release,
 644         .owner = THIS_MODULE,
 645 };
 646
 647 static int acpi_ec_add_fs(struct acpi_device *device)
 648 {
 649         struct proc_dir_entry *entry = NULL;
 650
 651         if (!acpi_device_dir(device)) {
 652                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
 653                                                      acpi_ec_dir);
 654                 if (!acpi_device_dir(device))
 655                         return -ENODEV;
 656         }
 657
 658         entry = create_proc_entry(ACPI_EC_FILE_INFO, S_IRUGO,
 659                                   acpi_device_dir(device));
 660         if (!entry)
 661                 return -ENODEV;
 662         else {
 663                 entry->proc_fops = &acpi_ec_info_ops;
 664                 entry->data = acpi_driver_data(device);
 665                 entry->owner = THIS_MODULE;
 666         }
 667
 668         return 0;
 669 }
 670
 671 static int acpi_ec_remove_fs(struct acpi_device *device)
 672 {
 673
 674         if (acpi_device_dir(device)) {
 675                 remove_proc_entry(ACPI_EC_FILE_INFO, acpi_device_dir(device));
 676                 remove_proc_entry(acpi_device_bid(device), acpi_ec_dir);
 677                 acpi_device_dir(device) = NULL;
 678         }
 679
 680         return 0;
 681 }
 682
 683 /* --------------------------------------------------------------------------
 684                                Driver Interface
 685    -------------------------------------------------------------------------- */
 686 static acpi_status
 687 ec_parse_io_ports(struct acpi_resource *resource, void *context);
 688
 689 static struct acpi_ec *make_acpi_ec(void)
 690 {
 691         struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
 692         if (!ec)
 693                 return NULL;
 694         ec->flags = 1 << EC_FLAGS_QUERY_PENDING;
 695         mutex_init(&ec->lock);
 696         init_waitqueue_head(&ec->wait);
 697         INIT_LIST_HEAD(&ec->list);
 698         return ec;
 699 }
 700
 701 static acpi_status
 702 acpi_ec_register_query_methods(acpi_handle handle, u32 level,
 703                                void *context, void **return_value)
 704 {
 705         struct acpi_namespace_node *node = handle;
 706         struct acpi_ec *ec = context;
 707         int value = 0;
 708         if (sscanf(node->name.ascii, "_Q%x", &value) == 1) {
 709                 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL);
 710         }
 711         return AE_OK;
 712 }
 713
 714 static acpi_status
 715 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
 716 {
 717         acpi_status status;
 718
 719         struct acpi_ec *ec = context;
 720         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
 721                                      ec_parse_io_ports, ec);
 722         if (ACPI_FAILURE(status))
 723                 return status;
 724
 725         /* Get GPE bit assignment (EC events). */
 726         /* TODO: Add support for _GPE returning a package */
 727         status = acpi_evaluate_integer(handle, "_GPE", NULL, &ec->gpe);
 728         if (ACPI_FAILURE(status))
 729                 return status;
 730         /* Find and register all query methods */
 731         acpi_walk_namespace(ACPI_TYPE_METHOD, handle, 1,
 732                             acpi_ec_register_query_methods, ec, NULL);
 733         /* Use the global lock for all EC transactions? */
 734         acpi_evaluate_integer(handle, "_GLK", NULL, &ec->global_lock);
 735         ec->handle = handle;
 736         return AE_CTRL_TERMINATE;
 737 }
 738
 739 static void ec_remove_handlers(struct acpi_ec *ec)
 740 {
 741         if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle,
 742                                 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler)))
 743                 pr_err(PREFIX "failed to remove space handler\n");
 744         if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe,
 745                                 &acpi_ec_gpe_handler)))
 746                 pr_err(PREFIX "failed to remove gpe handler\n");
 747         ec->handlers_installed = 0;
 748 }
 749
 750 static int acpi_ec_add(struct acpi_device *device)
 751 {
 752         struct acpi_ec *ec = NULL;
 753
 754         if (!device)
 755                 return -EINVAL;
 756         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
 757         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
 758
 759         /* Check for boot EC */
 760         if (boot_ec) {
 761                 if (boot_ec->handle == device->handle) {
 762                         /* Pre-loaded EC from DSDT, just move pointer */
 763                         ec = boot_ec;
 764                         boot_ec = NULL;
 765                         goto end;
 766                 } else if (boot_ec->handle == ACPI_ROOT_OBJECT) {
 767                         /* ECDT-based EC, time to shut it down */
 768                         ec_remove_handlers(boot_ec);
 769                         kfree(boot_ec);
 770                         first_ec = boot_ec = NULL;
 771                 }
 772         }
 773
 774         ec = make_acpi_ec();
 775         if (!ec)
 776                 return -ENOMEM;
 777
 778         if (ec_parse_device(device->handle, 0, ec, NULL) !=
 779             AE_CTRL_TERMINATE) {
 780                 kfree(ec);
 781                 return -EINVAL;
 782         }
 783         ec->handle = device->handle;
 784       end:
 785         if (!first_ec)
 786                 first_ec = ec;
 787         acpi_driver_data(device) = ec;
 788         acpi_ec_add_fs(device);
 789         pr_info(PREFIX "GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n",
 790                           ec->gpe, ec->command_addr, ec->data_addr);
 791         pr_info(PREFIX "driver started in %s mode\n",
 792                 (test_bit(EC_FLAGS_GPE_MODE, &ec->flags))?"interrupt":"poll");
 793         return 0;
 794 }
 795
 796 static int acpi_ec_remove(struct acpi_device *device, int type)
 797 {
 798         struct acpi_ec *ec;
 799         struct acpi_ec_query_handler *handler, *tmp;
 800
 801         if (!device)
 802                 return -EINVAL;
 803
 804         ec = acpi_driver_data(device);
 805         mutex_lock(&ec->lock);
 806         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
 807                 list_del(&handler->node);
 808                 kfree(handler);
 809         }
 810         mutex_unlock(&ec->lock);
 811         acpi_ec_remove_fs(device);
 812         acpi_driver_data(device) = NULL;
 813         if (ec == first_ec)
 814                 first_ec = NULL;
 815         kfree(ec);
 816         return 0;
 817 }
 818
 819 static acpi_status
 820 ec_parse_io_ports(struct acpi_resource *resource, void *context)
 821 {
 822         struct acpi_ec *ec = context;
 823
 824         if (resource->type != ACPI_RESOURCE_TYPE_IO)
 825                 return AE_OK;
 826
 827         /*
 828          * The first address region returned is the data port, and
 829          * the second address region returned is the status/command
 830          * port.
 831          */
 832         if (ec->data_addr == 0)
 833                 ec->data_addr = resource->data.io.minimum;
 834         else if (ec->command_addr == 0)
 835                 ec->command_addr = resource->data.io.minimum;
 836         else
 837                 return AE_CTRL_TERMINATE;
 838
 839         return AE_OK;
 840 }
 841
 842 static int ec_install_handlers(struct acpi_ec *ec)
 843 {
 844         acpi_status status;
 845         if (ec->handlers_installed)
 846                 return 0;
 847         status = acpi_install_gpe_handler(NULL, ec->gpe,
 848                                           ACPI_GPE_EDGE_TRIGGERED,
 849                                           &acpi_ec_gpe_handler, ec);
 850         if (ACPI_FAILURE(status))
 851                 return -ENODEV;
 852
 853         acpi_set_gpe_type(NULL, ec->gpe, ACPI_GPE_TYPE_RUNTIME);
 854         acpi_enable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
 855
 856         status = acpi_install_address_space_handler(ec->handle,
 857                                                     ACPI_ADR_SPACE_EC,
 858                                                     &acpi_ec_space_handler,
 859                                                     &acpi_ec_space_setup, ec);
 860         if (ACPI_FAILURE(status)) {
 861                 acpi_remove_gpe_handler(NULL, ec->gpe, &acpi_ec_gpe_handler);
 862                 return -ENODEV;
 863         }
 864
 865         ec->handlers_installed = 1;
 866         return 0;
 867 }
 868
 869 static int acpi_ec_start(struct acpi_device *device)
 870 {
 871         struct acpi_ec *ec;
 872         int ret = 0;
 873
 874         if (!device)
 875                 return -EINVAL;
 876
 877         ec = acpi_driver_data(device);
 878
 879         if (!ec)
 880                 return -EINVAL;
 881
 882         ret = ec_install_handlers(ec);
 883
 884         /* EC is fully operational, allow queries */
 885         clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
 886         return ret;
 887 }
 888
 889 static int acpi_ec_stop(struct acpi_device *device, int type)
 890 {
 891         struct acpi_ec *ec;
 892         if (!device)
 893                 return -EINVAL;
 894         ec = acpi_driver_data(device);
 895         if (!ec)
 896                 return -EINVAL;
 897         ec_remove_handlers(ec);
 898
 899         return 0;
 900 }
 901
 902 int __init acpi_ec_ecdt_probe(void)
 903 {
 904         int ret;
 905         acpi_status status;
 906         struct acpi_table_ecdt *ecdt_ptr;
 907
 908         boot_ec = make_acpi_ec();
 909         if (!boot_ec)
 910                 return -ENOMEM;
 911         /*
 912          * Generate a boot ec context
 913          */
 914         status = acpi_get_table(ACPI_SIG_ECDT, 1,
 915                                 (struct acpi_table_header **)&ecdt_ptr);
 916         if (ACPI_SUCCESS(status)) {
 917                 pr_info(PREFIX "EC description table is found, configuring boot EC\n");
 918                 boot_ec->command_addr = ecdt_ptr->control.address;
 919                 boot_ec->data_addr = ecdt_ptr->data.address;
 920                 boot_ec->gpe = ecdt_ptr->gpe;
 921                 boot_ec->handle = ACPI_ROOT_OBJECT;
 922         } else {
 923                 /* This workaround is needed only on some broken machines,
 924                  * which require early EC, but fail to provide ECDT */
 925                 acpi_handle x;
 926                 printk(KERN_DEBUG PREFIX "Look up EC in DSDT\n");
 927                 status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device,
 928                                                 boot_ec, NULL);
 929                 /* Check that acpi_get_devices actually find something */
 930                 if (ACPI_FAILURE(status) || !boot_ec->handle)
 931                         goto error;
 932                 /* We really need to limit this workaround, the only ASUS,
 933                  * which needs it, has fake EC._INI method, so use it as flag.
 934                  */
 935                 if (ACPI_FAILURE(acpi_get_handle(boot_ec->handle, "_INI", &x)))
 936                         goto error;
 937         }
 938
 939         ret = ec_install_handlers(boot_ec);
 940         if (!ret) {
 941                 first_ec = boot_ec;
 942                 return 0;
 943         }
 944       error:
 945         kfree(boot_ec);
 946         boot_ec = NULL;
 947         return -ENODEV;
 948 }
 949
 950 static int __init acpi_ec_init(void)
 951 {
 952         int result = 0;
 953
 954         if (acpi_disabled)
 955                 return 0;
 956
 957         acpi_ec_dir = proc_mkdir(ACPI_EC_CLASS, acpi_root_dir);
 958         if (!acpi_ec_dir)
 959                 return -ENODEV;
 960
 961         /* Now register the driver for the EC */
 962         result = acpi_bus_register_driver(&acpi_ec_driver);
 963         if (result < 0) {
 964                 remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
 965                 return -ENODEV;
 966         }
 967
 968         return result;
 969 }
 970
 971 subsys_initcall(acpi_ec_init);
 972
 973 /* EC driver currently not unloadable */
 974 #if 0
 975 static void __exit acpi_ec_exit(void)
 976 {
 977
 978         acpi_bus_unregister_driver(&acpi_ec_driver);
 979
 980         remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
 981
 982         return;
 983 }
 984 #endif  /* 0 */