drivers/acpi/ec.c

   1 /*
   2  *  ec.c - ACPI Embedded Controller Driver (v2.1)
   3  *
   4  *  Copyright (C) 2006-2008 Alexey Starikovskiy <astarikovskiy@suse.de>
   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 printout */
  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 <linux/spinlock.h>
  42 #include <asm/io.h>
  43 #include <acpi/acpi_bus.h>
  44 #include <acpi/acpi_drivers.h>
  45 #include <linux/dmi.h>
  46
  47 #define ACPI_EC_CLASS                   "embedded_controller"
  48 #define ACPI_EC_DEVICE_NAME             "Embedded Controller"
  49 #define ACPI_EC_FILE_INFO               "info"
  50
  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 #define ACPI_EC_DELAY           500     /* Wait 500ms max. during EC ops */
  69 #define ACPI_EC_UDELAY_GLK      1000    /* Wait 1ms max. to get global lock */
  70 #define ACPI_EC_CDELAY          10      /* Wait 10us before polling EC */
  71 #define ACPI_EC_MSI_UDELAY      550     /* Wait 550us for MSI EC */
  72
  73 #define ACPI_EC_STORM_THRESHOLD 8       /* number of false interrupts
  74                                            per one transaction */
  75
  76 enum {
  77         EC_FLAGS_QUERY_PENDING,         /* Query is pending */
  78         EC_FLAGS_GPE_STORM,             /* GPE storm detected */
  79         EC_FLAGS_HANDLERS_INSTALLED,    /* Handlers for GPE and
  80                                          * OpReg are installed */
  81         EC_FLAGS_FROZEN,                /* Transactions are suspended */
  82 };
  83
  84 /* If we find an EC via the ECDT, we need to keep a ptr to its context */
  85 /* External interfaces use first EC only, so remember */
  86 typedef int (*acpi_ec_query_func) (void *data);
  87
  88 struct acpi_ec_query_handler {
  89         struct list_head node;
  90         acpi_ec_query_func func;
  91         acpi_handle handle;
  92         void *data;
  93         u8 query_bit;
  94 };
  95
  96 struct transaction {
  97         const u8 *wdata;
  98         u8 *rdata;
  99         unsigned short irq_count;
 100         u8 command;
 101         u8 wi;
 102         u8 ri;
 103         u8 wlen;
 104         u8 rlen;
 105         bool done;
 106 };
 107
 108 static struct acpi_ec {
 109         acpi_handle handle;
 110         unsigned long gpe;
 111         unsigned long command_addr;
 112         unsigned long data_addr;
 113         unsigned long global_lock;
 114         unsigned long flags;
 115         struct mutex lock;
 116         wait_queue_head_t wait;
 117         struct list_head list;
 118         struct transaction *curr;
 119         spinlock_t curr_lock;
 120 } *boot_ec, *first_ec;
 121
 122 static int EC_FLAGS_MSI; /* Out-of-spec MSI controller */
 123 static int EC_FLAGS_VALIDATE_ECDT; /* ASUStec ECDTs need to be validated */
 124 static int EC_FLAGS_SKIP_DSDT_SCAN; /* Not all BIOS survive early DSDT scan */
 125
 126 /* --------------------------------------------------------------------------
 127                              Transaction Management
 128    -------------------------------------------------------------------------- */
 129
 130 static inline u8 acpi_ec_read_status(struct acpi_ec *ec)
 131 {
 132         u8 x = inb(ec->command_addr);
 133         pr_debug(PREFIX "---> status = 0x%2.2x\n", x);
 134         return x;
 135 }
 136
 137 static inline u8 acpi_ec_read_data(struct acpi_ec *ec)
 138 {
 139         u8 x = inb(ec->data_addr);
 140         pr_debug(PREFIX "---> data = 0x%2.2x\n", x);
 141         return x;
 142 }
 143
 144 static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command)
 145 {
 146         pr_debug(PREFIX "<--- command = 0x%2.2x\n", command);
 147         outb(command, ec->command_addr);
 148 }
 149
 150 static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data)
 151 {
 152         pr_debug(PREFIX "<--- data = 0x%2.2x\n", data);
 153         outb(data, ec->data_addr);
 154 }
 155
 156 static int ec_transaction_done(struct acpi_ec *ec)
 157 {
 158         unsigned long flags;
 159         int ret = 0;
 160         spin_lock_irqsave(&ec->curr_lock, flags);
 161         if (!ec->curr || ec->curr->done)
 162                 ret = 1;
 163         spin_unlock_irqrestore(&ec->curr_lock, flags);
 164         return ret;
 165 }
 166
 167 static void start_transaction(struct acpi_ec *ec)
 168 {
 169         ec->curr->irq_count = ec->curr->wi = ec->curr->ri = 0;
 170         ec->curr->done = false;
 171         acpi_ec_write_cmd(ec, ec->curr->command);
 172 }
 173
 174 static void advance_transaction(struct acpi_ec *ec, u8 status)
 175 {
 176         unsigned long flags;
 177         spin_lock_irqsave(&ec->curr_lock, flags);
 178         if (!ec->curr)
 179                 goto unlock;
 180         if (ec->curr->wlen > ec->curr->wi) {
 181                 if ((status & ACPI_EC_FLAG_IBF) == 0)
 182                         acpi_ec_write_data(ec,
 183                                 ec->curr->wdata[ec->curr->wi++]);
 184                 else
 185                         goto err;
 186         } else if (ec->curr->rlen > ec->curr->ri) {
 187                 if ((status & ACPI_EC_FLAG_OBF) == 1) {
 188                         ec->curr->rdata[ec->curr->ri++] = acpi_ec_read_data(ec);
 189                         if (ec->curr->rlen == ec->curr->ri)
 190                                 ec->curr->done = true;
 191                 } else
 192                         goto err;
 193         } else if (ec->curr->wlen == ec->curr->wi &&
 194                    (status & ACPI_EC_FLAG_IBF) == 0)
 195                 ec->curr->done = true;
 196         goto unlock;
 197 err:
 198         /* false interrupt, state didn't change */
 199         if (in_interrupt())
 200                 ++ec->curr->irq_count;
 201 unlock:
 202         spin_unlock_irqrestore(&ec->curr_lock, flags);
 203 }
 204
 205 static int acpi_ec_sync_query(struct acpi_ec *ec);
 206
 207 static int ec_check_sci_sync(struct acpi_ec *ec, u8 state)
 208 {
 209         if (state & ACPI_EC_FLAG_SCI) {
 210                 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags))
 211                         return acpi_ec_sync_query(ec);
 212         }
 213         return 0;
 214 }
 215
 216 static int ec_poll(struct acpi_ec *ec)
 217 {
 218         unsigned long flags;
 219         int repeat = 2; /* number of command restarts */
 220         while (repeat--) {
 221                 unsigned long delay = jiffies +
 222                         msecs_to_jiffies(ACPI_EC_DELAY);
 223                 do {
 224                         /* don't sleep with disabled interrupts */
 225                         if (EC_FLAGS_MSI || irqs_disabled()) {
 226                                 udelay(ACPI_EC_MSI_UDELAY);
 227                                 if (ec_transaction_done(ec))
 228                                         return 0;
 229                         } else {
 230                                 if (wait_event_timeout(ec->wait,
 231                                                 ec_transaction_done(ec),
 232                                                 msecs_to_jiffies(1)))
 233                                         return 0;
 234                         }
 235                         advance_transaction(ec, acpi_ec_read_status(ec));
 236                 } while (time_before(jiffies, delay));
 237                 if (acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF)
 238                         break;
 239                 pr_debug(PREFIX "controller reset, restart transaction\n");
 240                 spin_lock_irqsave(&ec->curr_lock, flags);
 241                 start_transaction(ec);
 242                 spin_unlock_irqrestore(&ec->curr_lock, flags);
 243         }
 244         return -ETIME;
 245 }
 246
 247 static int acpi_ec_transaction_unlocked(struct acpi_ec *ec,
 248                                         struct transaction *t)
 249 {
 250         unsigned long tmp;
 251         int ret = 0;
 252         if (EC_FLAGS_MSI)
 253                 udelay(ACPI_EC_MSI_UDELAY);
 254         /* start transaction */
 255         spin_lock_irqsave(&ec->curr_lock, tmp);
 256         /* following two actions should be kept atomic */
 257         ec->curr = t;
 258         start_transaction(ec);
 259         if (ec->curr->command == ACPI_EC_COMMAND_QUERY)
 260                 clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
 261         spin_unlock_irqrestore(&ec->curr_lock, tmp);
 262         ret = ec_poll(ec);
 263         spin_lock_irqsave(&ec->curr_lock, tmp);
 264         ec->curr = NULL;
 265         spin_unlock_irqrestore(&ec->curr_lock, tmp);
 266         return ret;
 267 }
 268
 269 static int ec_check_ibf0(struct acpi_ec *ec)
 270 {
 271         u8 status = acpi_ec_read_status(ec);
 272         return (status & ACPI_EC_FLAG_IBF) == 0;
 273 }
 274
 275 static int ec_wait_ibf0(struct acpi_ec *ec)
 276 {
 277         unsigned long delay = jiffies + msecs_to_jiffies(ACPI_EC_DELAY);
 278         /* interrupt wait manually if GPE mode is not active */
 279         while (time_before(jiffies, delay))
 280                 if (wait_event_timeout(ec->wait, ec_check_ibf0(ec),
 281                                         msecs_to_jiffies(1)))
 282                         return 0;
 283         return -ETIME;
 284 }
 285
 286 static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t)
 287 {
 288         int status;
 289         u32 glk;
 290         if (!ec || (!t) || (t->wlen && !t->wdata) || (t->rlen && !t->rdata))
 291                 return -EINVAL;
 292         if (t->rdata)
 293                 memset(t->rdata, 0, t->rlen);
 294         mutex_lock(&ec->lock);
 295         if (test_bit(EC_FLAGS_FROZEN, &ec->flags)) {
 296                 status = -EINVAL;
 297                 goto unlock;
 298         }
 299         if (ec->global_lock) {
 300                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 301                 if (ACPI_FAILURE(status)) {
 302                         status = -ENODEV;
 303                         goto unlock;
 304                 }
 305         }
 306         if (ec_wait_ibf0(ec)) {
 307                 pr_err(PREFIX "input buffer is not empty, "
 308                                 "aborting transaction\n");
 309                 status = -ETIME;
 310                 goto end;
 311         }
 312         pr_debug(PREFIX "transaction start\n");
 313         /* disable GPE during transaction if storm is detected */
 314         if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
 315                 acpi_disable_gpe(NULL, ec->gpe);
 316         }
 317
 318         status = acpi_ec_transaction_unlocked(ec, t);
 319
 320         /* check if we received SCI during transaction */
 321         ec_check_sci_sync(ec, acpi_ec_read_status(ec));
 322         if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
 323                 msleep(1);
 324                 /* it is safe to enable GPE outside of transaction */
 325                 acpi_enable_gpe(NULL, ec->gpe);
 326         } else if (t->irq_count > ACPI_EC_STORM_THRESHOLD) {
 327                 pr_info(PREFIX "GPE storm detected, "
 328                         "transactions will use polling mode\n");
 329                 set_bit(EC_FLAGS_GPE_STORM, &ec->flags);
 330         }
 331         pr_debug(PREFIX "transaction end\n");
 332 end:
 333         if (ec->global_lock)
 334                 acpi_release_global_lock(glk);
 335 unlock:
 336         mutex_unlock(&ec->lock);
 337         return status;
 338 }
 339
 340 static int acpi_ec_burst_enable(struct acpi_ec *ec)
 341 {
 342         u8 d;
 343         struct transaction t = {.command = ACPI_EC_BURST_ENABLE,
 344                                 .wdata = NULL, .rdata = &d,
 345                                 .wlen = 0, .rlen = 1};
 346
 347         return acpi_ec_transaction(ec, &t);
 348 }
 349
 350 static int acpi_ec_burst_disable(struct acpi_ec *ec)
 351 {
 352         struct transaction t = {.command = ACPI_EC_BURST_DISABLE,
 353                                 .wdata = NULL, .rdata = NULL,
 354                                 .wlen = 0, .rlen = 0};
 355
 356         return (acpi_ec_read_status(ec) & ACPI_EC_FLAG_BURST) ?
 357                                 acpi_ec_transaction(ec, &t) : 0;
 358 }
 359
 360 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 * data)
 361 {
 362         int result;
 363         u8 d;
 364         struct transaction t = {.command = ACPI_EC_COMMAND_READ,
 365                                 .wdata = &address, .rdata = &d,
 366                                 .wlen = 1, .rlen = 1};
 367
 368         result = acpi_ec_transaction(ec, &t);
 369         *data = d;
 370         return result;
 371 }
 372
 373 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
 374 {
 375         u8 wdata[2] = { address, data };
 376         struct transaction t = {.command = ACPI_EC_COMMAND_WRITE,
 377                                 .wdata = wdata, .rdata = NULL,
 378                                 .wlen = 2, .rlen = 0};
 379
 380         return acpi_ec_transaction(ec, &t);
 381 }
 382
 383 /*
 384  * Externally callable EC access functions. For now, assume 1 EC only
 385  */
 386 int ec_burst_enable(void)
 387 {
 388         if (!first_ec)
 389                 return -ENODEV;
 390         return acpi_ec_burst_enable(first_ec);
 391 }
 392
 393 EXPORT_SYMBOL(ec_burst_enable);
 394
 395 int ec_burst_disable(void)
 396 {
 397         if (!first_ec)
 398                 return -ENODEV;
 399         return acpi_ec_burst_disable(first_ec);
 400 }
 401
 402 EXPORT_SYMBOL(ec_burst_disable);
 403
 404 int ec_read(u8 addr, u8 * val)
 405 {
 406         int err;
 407         u8 temp_data;
 408
 409         if (!first_ec)
 410                 return -ENODEV;
 411
 412         err = acpi_ec_read(first_ec, addr, &temp_data);
 413
 414         if (!err) {
 415                 *val = temp_data;
 416                 return 0;
 417         } else
 418                 return err;
 419 }
 420
 421 EXPORT_SYMBOL(ec_read);
 422
 423 int ec_write(u8 addr, u8 val)
 424 {
 425         int err;
 426
 427         if (!first_ec)
 428                 return -ENODEV;
 429
 430         err = acpi_ec_write(first_ec, addr, val);
 431
 432         return err;
 433 }
 434
 435 EXPORT_SYMBOL(ec_write);
 436
 437 int ec_transaction(u8 command,
 438                    const u8 * wdata, unsigned wdata_len,
 439                    u8 * rdata, unsigned rdata_len,
 440                    int force_poll)
 441 {
 442         struct transaction t = {.command = command,
 443                                 .wdata = wdata, .rdata = rdata,
 444                                 .wlen = wdata_len, .rlen = rdata_len};
 445         if (!first_ec)
 446                 return -ENODEV;
 447
 448         return acpi_ec_transaction(first_ec, &t);
 449 }
 450
 451 EXPORT_SYMBOL(ec_transaction);
 452
 453 void acpi_ec_suspend_transactions(void)
 454 {
 455         struct acpi_ec *ec = first_ec;
 456
 457         if (!ec)
 458                 return;
 459
 460         mutex_lock(&ec->lock);
 461         /* Prevent transactions from being carried out */
 462         set_bit(EC_FLAGS_FROZEN, &ec->flags);
 463         mutex_unlock(&ec->lock);
 464 }
 465
 466 void acpi_ec_resume_transactions(void)
 467 {
 468         struct acpi_ec *ec = first_ec;
 469
 470         if (!ec)
 471                 return;
 472
 473         mutex_lock(&ec->lock);
 474         /* Allow transactions to be carried out again */
 475         clear_bit(EC_FLAGS_FROZEN, &ec->flags);
 476         mutex_unlock(&ec->lock);
 477 }
 478
 479 static int acpi_ec_query_unlocked(struct acpi_ec *ec, u8 * data)
 480 {
 481         int result;
 482         u8 d;
 483         struct transaction t = {.command = ACPI_EC_COMMAND_QUERY,
 484                                 .wdata = NULL, .rdata = &d,
 485                                 .wlen = 0, .rlen = 1};
 486         if (!ec || !data)
 487                 return -EINVAL;
 488         /*
 489          * Query the EC to find out which _Qxx method we need to evaluate.
 490          * Note that successful completion of the query causes the ACPI_EC_SCI
 491          * bit to be cleared (and thus clearing the interrupt source).
 492          */
 493         result = acpi_ec_transaction_unlocked(ec, &t);
 494         if (result)
 495                 return result;
 496         if (!d)
 497                 return -ENODATA;
 498         *data = d;
 499         return 0;
 500 }
 501
 502 /* --------------------------------------------------------------------------
 503                                 Event Management
 504    -------------------------------------------------------------------------- */
 505 int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
 506                               acpi_handle handle, acpi_ec_query_func func,
 507                               void *data)
 508 {
 509         struct acpi_ec_query_handler *handler =
 510             kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL);
 511         if (!handler)
 512                 return -ENOMEM;
 513
 514         handler->query_bit = query_bit;
 515         handler->handle = handle;
 516         handler->func = func;
 517         handler->data = data;
 518         mutex_lock(&ec->lock);
 519         list_add(&handler->node, &ec->list);
 520         mutex_unlock(&ec->lock);
 521         return 0;
 522 }
 523
 524 EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler);
 525
 526 void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit)
 527 {
 528         struct acpi_ec_query_handler *handler, *tmp;
 529         mutex_lock(&ec->lock);
 530         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
 531                 if (query_bit == handler->query_bit) {
 532                         list_del(&handler->node);
 533                         kfree(handler);
 534                 }
 535         }
 536         mutex_unlock(&ec->lock);
 537 }
 538
 539 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler);
 540
 541 static void acpi_ec_run(void *cxt)
 542 {
 543         struct acpi_ec_query_handler *handler = cxt;
 544         if (!handler)
 545                 return;
 546         pr_debug(PREFIX "start query execution\n");
 547         if (handler->func)
 548                 handler->func(handler->data);
 549         else if (handler->handle)
 550                 acpi_evaluate_object(handler->handle, NULL, NULL, NULL);
 551         pr_debug(PREFIX "stop query execution\n");
 552         kfree(handler);
 553 }
 554
 555 static int acpi_ec_sync_query(struct acpi_ec *ec)
 556 {
 557         u8 value = 0;
 558         int status;
 559         struct acpi_ec_query_handler *handler, *copy;
 560         if ((status = acpi_ec_query_unlocked(ec, &value)))
 561                 return status;
 562         list_for_each_entry(handler, &ec->list, node) {
 563                 if (value == handler->query_bit) {
 564                         /* have custom handler for this bit */
 565                         copy = kmalloc(sizeof(*handler), GFP_KERNEL);
 566                         if (!copy)
 567                                 return -ENOMEM;
 568                         memcpy(copy, handler, sizeof(*copy));
 569                         pr_debug(PREFIX "push query execution (0x%2x) on queue\n", value);
 570                         return acpi_os_execute((copy->func) ?
 571                                 OSL_NOTIFY_HANDLER : OSL_GPE_HANDLER,
 572                                 acpi_ec_run, copy);
 573                 }
 574         }
 575         return 0;
 576 }
 577
 578 static void acpi_ec_gpe_query(void *ec_cxt)
 579 {
 580         struct acpi_ec *ec = ec_cxt;
 581         if (!ec)
 582                 return;
 583         mutex_lock(&ec->lock);
 584         acpi_ec_sync_query(ec);
 585         mutex_unlock(&ec->lock);
 586 }
 587
 588 static void acpi_ec_gpe_query(void *ec_cxt);
 589
 590 static int ec_check_sci(struct acpi_ec *ec, u8 state)
 591 {
 592         if (state & ACPI_EC_FLAG_SCI) {
 593                 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) {
 594                         pr_debug(PREFIX "push gpe query to the queue\n");
 595                         return acpi_os_execute(OSL_NOTIFY_HANDLER,
 596                                 acpi_ec_gpe_query, ec);
 597                 }
 598         }
 599         return 0;
 600 }
 601
 602 static u32 acpi_ec_gpe_handler(void *data)
 603 {
 604         struct acpi_ec *ec = data;
 605
 606         pr_debug(PREFIX "~~~> interrupt\n");
 607
 608         advance_transaction(ec, acpi_ec_read_status(ec));
 609         if (ec_transaction_done(ec) &&
 610             (acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF) == 0) {
 611                 wake_up(&ec->wait);
 612                 ec_check_sci(ec, acpi_ec_read_status(ec));
 613         }
 614         return ACPI_INTERRUPT_HANDLED;
 615 }
 616
 617 /* --------------------------------------------------------------------------
 618                              Address Space Management
 619    -------------------------------------------------------------------------- */
 620
 621 static acpi_status
 622 acpi_ec_space_handler(u32 function, acpi_physical_address address,
 623                       u32 bits, acpi_integer *value,
 624                       void *handler_context, void *region_context)
 625 {
 626         struct acpi_ec *ec = handler_context;
 627         int result = 0, i;
 628         u8 temp = 0;
 629
 630         if ((address > 0xFF) || !value || !handler_context)
 631                 return AE_BAD_PARAMETER;
 632
 633         if (function != ACPI_READ && function != ACPI_WRITE)
 634                 return AE_BAD_PARAMETER;
 635
 636         if (bits != 8 && acpi_strict)
 637                 return AE_BAD_PARAMETER;
 638
 639         if (EC_FLAGS_MSI)
 640                 acpi_ec_burst_enable(ec);
 641
 642         if (function == ACPI_READ) {
 643                 result = acpi_ec_read(ec, address, &temp);
 644                 *value = temp;
 645         } else {
 646                 temp = 0xff & (*value);
 647                 result = acpi_ec_write(ec, address, temp);
 648         }
 649
 650         for (i = 8; unlikely(bits - i > 0); i += 8) {
 651                 ++address;
 652                 if (function == ACPI_READ) {
 653                         result = acpi_ec_read(ec, address, &temp);
 654                         (*value) |= ((acpi_integer)temp) << i;
 655                 } else {
 656                         temp = 0xff & ((*value) >> i);
 657                         result = acpi_ec_write(ec, address, temp);
 658                 }
 659         }
 660
 661         if (EC_FLAGS_MSI)
 662                 acpi_ec_burst_disable(ec);
 663
 664         switch (result) {
 665         case -EINVAL:
 666                 return AE_BAD_PARAMETER;
 667                 break;
 668         case -ENODEV:
 669                 return AE_NOT_FOUND;
 670                 break;
 671         case -ETIME:
 672                 return AE_TIME;
 673                 break;
 674         default:
 675                 return AE_OK;
 676         }
 677 }
 678
 679 /* --------------------------------------------------------------------------
 680                               FS Interface (/proc)
 681    -------------------------------------------------------------------------- */
 682
 683 static struct proc_dir_entry *acpi_ec_dir;
 684
 685 static int acpi_ec_read_info(struct seq_file *seq, void *offset)
 686 {
 687         struct acpi_ec *ec = seq->private;
 688
 689         if (!ec)
 690                 goto end;
 691
 692         seq_printf(seq, "gpe:\t\t\t0x%02x\n", (u32) ec->gpe);
 693         seq_printf(seq, "ports:\t\t\t0x%02x, 0x%02x\n",
 694                    (unsigned)ec->command_addr, (unsigned)ec->data_addr);
 695         seq_printf(seq, "use global lock:\t%s\n",
 696                    ec->global_lock ? "yes" : "no");
 697       end:
 698         return 0;
 699 }
 700
 701 static int acpi_ec_info_open_fs(struct inode *inode, struct file *file)
 702 {
 703         return single_open(file, acpi_ec_read_info, PDE(inode)->data);
 704 }
 705
 706 static const struct file_operations acpi_ec_info_ops = {
 707         .open = acpi_ec_info_open_fs,
 708         .read = seq_read,
 709         .llseek = seq_lseek,
 710         .release = single_release,
 711         .owner = THIS_MODULE,
 712 };
 713
 714 static int acpi_ec_add_fs(struct acpi_device *device)
 715 {
 716         struct proc_dir_entry *entry = NULL;
 717
 718         if (!acpi_device_dir(device)) {
 719                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
 720                                                      acpi_ec_dir);
 721                 if (!acpi_device_dir(device))
 722                         return -ENODEV;
 723         }
 724
 725         entry = proc_create_data(ACPI_EC_FILE_INFO, S_IRUGO,
 726                                  acpi_device_dir(device),
 727                                  &acpi_ec_info_ops, acpi_driver_data(device));
 728         if (!entry)
 729                 return -ENODEV;
 730         return 0;
 731 }
 732
 733 static int acpi_ec_remove_fs(struct acpi_device *device)
 734 {
 735
 736         if (acpi_device_dir(device)) {
 737                 remove_proc_entry(ACPI_EC_FILE_INFO, acpi_device_dir(device));
 738                 remove_proc_entry(acpi_device_bid(device), acpi_ec_dir);
 739                 acpi_device_dir(device) = NULL;
 740         }
 741
 742         return 0;
 743 }
 744
 745 /* --------------------------------------------------------------------------
 746                                Driver Interface
 747    -------------------------------------------------------------------------- */
 748 static acpi_status
 749 ec_parse_io_ports(struct acpi_resource *resource, void *context);
 750
 751 static struct acpi_ec *make_acpi_ec(void)
 752 {
 753         struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
 754         if (!ec)
 755                 return NULL;
 756         ec->flags = 1 << EC_FLAGS_QUERY_PENDING;
 757         mutex_init(&ec->lock);
 758         init_waitqueue_head(&ec->wait);
 759         INIT_LIST_HEAD(&ec->list);
 760         spin_lock_init(&ec->curr_lock);
 761         return ec;
 762 }
 763
 764 static acpi_status
 765 acpi_ec_register_query_methods(acpi_handle handle, u32 level,
 766                                void *context, void **return_value)
 767 {
 768         char node_name[5];
 769         struct acpi_buffer buffer = { sizeof(node_name), node_name };
 770         struct acpi_ec *ec = context;
 771         int value = 0;
 772         acpi_status status;
 773
 774         status = acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
 775
 776         if (ACPI_SUCCESS(status) && sscanf(node_name, "_Q%x", &value) == 1) {
 777                 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL);
 778         }
 779         return AE_OK;
 780 }
 781
 782 static acpi_status
 783 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
 784 {
 785         acpi_status status;
 786         unsigned long long tmp = 0;
 787
 788         struct acpi_ec *ec = context;
 789
 790         /* clear addr values, ec_parse_io_ports depend on it */
 791         ec->command_addr = ec->data_addr = 0;
 792
 793         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
 794                                      ec_parse_io_ports, ec);
 795         if (ACPI_FAILURE(status))
 796                 return status;
 797
 798         /* Get GPE bit assignment (EC events). */
 799         /* TODO: Add support for _GPE returning a package */
 800         status = acpi_evaluate_integer(handle, "_GPE", NULL, &tmp);
 801         if (ACPI_FAILURE(status))
 802                 return status;
 803         ec->gpe = tmp;
 804         /* Use the global lock for all EC transactions? */
 805         tmp = 0;
 806         acpi_evaluate_integer(handle, "_GLK", NULL, &tmp);
 807         ec->global_lock = tmp;
 808         ec->handle = handle;
 809         return AE_CTRL_TERMINATE;
 810 }
 811
 812 static int ec_install_handlers(struct acpi_ec *ec)
 813 {
 814         acpi_status status;
 815         if (test_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags))
 816                 return 0;
 817         status = acpi_install_gpe_handler(NULL, ec->gpe,
 818                                   ACPI_GPE_EDGE_TRIGGERED,
 819                                   &acpi_ec_gpe_handler, ec);
 820         if (ACPI_FAILURE(status))
 821                 return -ENODEV;
 822         acpi_set_gpe_type(NULL, ec->gpe, ACPI_GPE_TYPE_RUNTIME);
 823         acpi_enable_gpe(NULL, ec->gpe);
 824         status = acpi_install_address_space_handler(ec->handle,
 825                                                     ACPI_ADR_SPACE_EC,
 826                                                     &acpi_ec_space_handler,
 827                                                     NULL, ec);
 828         if (ACPI_FAILURE(status)) {
 829                 if (status == AE_NOT_FOUND) {
 830                         /*
 831                          * Maybe OS fails in evaluating the _REG object.
 832                          * The AE_NOT_FOUND error will be ignored and OS
 833                          * continue to initialize EC.
 834                          */
 835                         printk(KERN_ERR "Fail in evaluating the _REG object"
 836                                 " of EC device. Broken bios is suspected.\n");
 837                 } else {
 838                         acpi_remove_gpe_handler(NULL, ec->gpe,
 839                                 &acpi_ec_gpe_handler);
 840                         return -ENODEV;
 841                 }
 842         }
 843
 844         set_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
 845         return 0;
 846 }
 847
 848 static void ec_remove_handlers(struct acpi_ec *ec)
 849 {
 850         if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle,
 851                                 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler)))
 852                 pr_err(PREFIX "failed to remove space handler\n");
 853         if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe,
 854                                 &acpi_ec_gpe_handler)))
 855                 pr_err(PREFIX "failed to remove gpe handler\n");
 856         clear_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
 857 }
 858
 859 static int acpi_ec_add(struct acpi_device *device)
 860 {
 861         struct acpi_ec *ec = NULL;
 862         int ret;
 863
 864         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
 865         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
 866
 867         /* Check for boot EC */
 868         if (boot_ec &&
 869             (boot_ec->handle == device->handle ||
 870              boot_ec->handle == ACPI_ROOT_OBJECT)) {
 871                 ec = boot_ec;
 872                 boot_ec = NULL;
 873         } else {
 874                 ec = make_acpi_ec();
 875                 if (!ec)
 876                         return -ENOMEM;
 877         }
 878         if (ec_parse_device(device->handle, 0, ec, NULL) !=
 879                 AE_CTRL_TERMINATE) {
 880                         kfree(ec);
 881                         return -EINVAL;
 882         }
 883
 884         ec->handle = device->handle;
 885
 886         /* Find and register all query methods */
 887         acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1,
 888                             acpi_ec_register_query_methods, NULL, ec, NULL);
 889
 890         if (!first_ec)
 891                 first_ec = ec;
 892         device->driver_data = ec;
 893         acpi_ec_add_fs(device);
 894         pr_info(PREFIX "GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n",
 895                           ec->gpe, ec->command_addr, ec->data_addr);
 896
 897         ret = ec_install_handlers(ec);
 898
 899         /* EC is fully operational, allow queries */
 900         clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
 901         return ret;
 902 }
 903
 904 static int acpi_ec_remove(struct acpi_device *device, int type)
 905 {
 906         struct acpi_ec *ec;
 907         struct acpi_ec_query_handler *handler, *tmp;
 908
 909         if (!device)
 910                 return -EINVAL;
 911
 912         ec = acpi_driver_data(device);
 913         ec_remove_handlers(ec);
 914         mutex_lock(&ec->lock);
 915         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
 916                 list_del(&handler->node);
 917                 kfree(handler);
 918         }
 919         mutex_unlock(&ec->lock);
 920         acpi_ec_remove_fs(device);
 921         device->driver_data = NULL;
 922         if (ec == first_ec)
 923                 first_ec = NULL;
 924         kfree(ec);
 925         return 0;
 926 }
 927
 928 static acpi_status
 929 ec_parse_io_ports(struct acpi_resource *resource, void *context)
 930 {
 931         struct acpi_ec *ec = context;
 932
 933         if (resource->type != ACPI_RESOURCE_TYPE_IO)
 934                 return AE_OK;
 935
 936         /*
 937          * The first address region returned is the data port, and
 938          * the second address region returned is the status/command
 939          * port.
 940          */
 941         if (ec->data_addr == 0)
 942                 ec->data_addr = resource->data.io.minimum;
 943         else if (ec->command_addr == 0)
 944                 ec->command_addr = resource->data.io.minimum;
 945         else
 946                 return AE_CTRL_TERMINATE;
 947
 948         return AE_OK;
 949 }
 950
 951 int __init acpi_boot_ec_enable(void)
 952 {
 953         if (!boot_ec || test_bit(EC_FLAGS_HANDLERS_INSTALLED, &boot_ec->flags))
 954                 return 0;
 955         if (!ec_install_handlers(boot_ec)) {
 956                 first_ec = boot_ec;
 957                 return 0;
 958         }
 959         return -EFAULT;
 960 }
 961
 962 static const struct acpi_device_id ec_device_ids[] = {
 963         {"PNP0C09", 0},
 964         {"", 0},
 965 };
 966
 967 /* Some BIOS do not survive early DSDT scan, skip it */
 968 static int ec_skip_dsdt_scan(const struct dmi_system_id *id)
 969 {
 970         EC_FLAGS_SKIP_DSDT_SCAN = 1;
 971         return 0;
 972 }
 973
 974 /* ASUStek often supplies us with broken ECDT, validate it */
 975 static int ec_validate_ecdt(const struct dmi_system_id *id)
 976 {
 977         EC_FLAGS_VALIDATE_ECDT = 1;
 978         return 0;
 979 }
 980
 981 /* MSI EC needs special treatment, enable it */
 982 static int ec_flag_msi(const struct dmi_system_id *id)
 983 {
 984         printk(KERN_DEBUG PREFIX "Detected MSI hardware, enabling workarounds.\n");
 985         EC_FLAGS_MSI = 1;
 986         EC_FLAGS_VALIDATE_ECDT = 1;
 987         return 0;
 988 }
 989
 990 static struct dmi_system_id __initdata ec_dmi_table[] = {
 991         {
 992         ec_skip_dsdt_scan, "Compal JFL92", {
 993         DMI_MATCH(DMI_BIOS_VENDOR, "COMPAL"),
 994         DMI_MATCH(DMI_BOARD_NAME, "JFL92") }, NULL},
 995         {
 996         ec_flag_msi, "MSI hardware", {
 997         DMI_MATCH(DMI_BIOS_VENDOR, "Micro-Star")}, NULL},
 998         {
 999         ec_flag_msi, "MSI hardware", {
1000         DMI_MATCH(DMI_SYS_VENDOR, "Micro-Star")}, NULL},
1001         {
1002         ec_flag_msi, "MSI hardware", {
1003         DMI_MATCH(DMI_CHASSIS_VENDOR, "MICRO-Star")}, NULL},
1004         {
1005         ec_validate_ecdt, "ASUS hardware", {
1006         DMI_MATCH(DMI_BIOS_VENDOR, "ASUS") }, NULL},
1007         {},
1008 };
1009
1010
1011 int __init acpi_ec_ecdt_probe(void)
1012 {
1013         acpi_status status;
1014         struct acpi_ec *saved_ec = NULL;
1015         struct acpi_table_ecdt *ecdt_ptr;
1016
1017         boot_ec = make_acpi_ec();
1018         if (!boot_ec)
1019                 return -ENOMEM;
1020         /*
1021          * Generate a boot ec context
1022          */
1023         dmi_check_system(ec_dmi_table);
1024         status = acpi_get_table(ACPI_SIG_ECDT, 1,
1025                                 (struct acpi_table_header **)&ecdt_ptr);
1026         if (ACPI_SUCCESS(status)) {
1027                 pr_info(PREFIX "EC description table is found, configuring boot EC\n");
1028                 boot_ec->command_addr = ecdt_ptr->control.address;
1029                 boot_ec->data_addr = ecdt_ptr->data.address;
1030                 boot_ec->gpe = ecdt_ptr->gpe;
1031                 boot_ec->handle = ACPI_ROOT_OBJECT;
1032                 acpi_get_handle(ACPI_ROOT_OBJECT, ecdt_ptr->id, &boot_ec->handle);
1033                 /* Don't trust ECDT, which comes from ASUSTek */
1034                 if (!EC_FLAGS_VALIDATE_ECDT)
1035                         goto install;
1036                 saved_ec = kmalloc(sizeof(struct acpi_ec), GFP_KERNEL);
1037                 if (!saved_ec)
1038                         return -ENOMEM;
1039                 memcpy(saved_ec, boot_ec, sizeof(struct acpi_ec));
1040         /* fall through */
1041         }
1042
1043         if (EC_FLAGS_SKIP_DSDT_SCAN)
1044                 return -ENODEV;
1045
1046         /* This workaround is needed only on some broken machines,
1047          * which require early EC, but fail to provide ECDT */
1048         printk(KERN_DEBUG PREFIX "Look up EC in DSDT\n");
1049         status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device,
1050                                         boot_ec, NULL);
1051         /* Check that acpi_get_devices actually find something */
1052         if (ACPI_FAILURE(status) || !boot_ec->handle)
1053                 goto error;
1054         if (saved_ec) {
1055                 /* try to find good ECDT from ASUSTek */
1056                 if (saved_ec->command_addr != boot_ec->command_addr ||
1057                     saved_ec->data_addr != boot_ec->data_addr ||
1058                     saved_ec->gpe != boot_ec->gpe ||
1059                     saved_ec->handle != boot_ec->handle)
1060                         pr_info(PREFIX "ASUSTek keeps feeding us with broken "
1061                         "ECDT tables, which are very hard to workaround. "
1062                         "Trying to use DSDT EC info instead. Please send "
1063                         "output of acpidump to linux-acpi@vger.kernel.org\n");
1064                 kfree(saved_ec);
1065                 saved_ec = NULL;
1066         } else {
1067                 /* We really need to limit this workaround, the only ASUS,
1068                 * which needs it, has fake EC._INI method, so use it as flag.
1069                 * Keep boot_ec struct as it will be needed soon.
1070                 */
1071                 acpi_handle dummy;
1072                 if (!dmi_name_in_vendors("ASUS") ||
1073                     ACPI_FAILURE(acpi_get_handle(boot_ec->handle, "_INI",
1074                                                         &dummy)))
1075                         return -ENODEV;
1076         }
1077 install:
1078         if (!ec_install_handlers(boot_ec)) {
1079                 first_ec = boot_ec;
1080                 return 0;
1081         }
1082 error:
1083         kfree(boot_ec);
1084         boot_ec = NULL;
1085         return -ENODEV;
1086 }
1087
1088 static int acpi_ec_suspend(struct acpi_device *device, pm_message_t state)
1089 {
1090         struct acpi_ec *ec = acpi_driver_data(device);
1091         /* Stop using GPE */
1092         acpi_disable_gpe(NULL, ec->gpe);
1093         return 0;
1094 }
1095
1096 static int acpi_ec_resume(struct acpi_device *device)
1097 {
1098         struct acpi_ec *ec = acpi_driver_data(device);
1099         /* Enable use of GPE back */
1100         acpi_enable_gpe(NULL, ec->gpe);
1101         return 0;
1102 }
1103
1104 static struct acpi_driver acpi_ec_driver = {
1105         .name = "ec",
1106         .class = ACPI_EC_CLASS,
1107         .ids = ec_device_ids,
1108         .ops = {
1109                 .add = acpi_ec_add,
1110                 .remove = acpi_ec_remove,
1111                 .suspend = acpi_ec_suspend,
1112                 .resume = acpi_ec_resume,
1113                 },
1114 };
1115
1116 int __init acpi_ec_init(void)
1117 {
1118         int result = 0;
1119
1120         acpi_ec_dir = proc_mkdir(ACPI_EC_CLASS, acpi_root_dir);
1121         if (!acpi_ec_dir)
1122                 return -ENODEV;
1123
1124         /* Now register the driver for the EC */
1125         result = acpi_bus_register_driver(&acpi_ec_driver);
1126         if (result < 0) {
1127                 remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1128                 return -ENODEV;
1129         }
1130
1131         return result;
1132 }
1133
1134 /* EC driver currently not unloadable */
1135 #if 0
1136 static void __exit acpi_ec_exit(void)
1137 {
1138
1139         acpi_bus_unregister_driver(&acpi_ec_driver);
1140
1141         remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1142
1143         return;
1144 }
1145 #endif  /* 0 */