Pileus Git - ~andy/linux/blob - 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/interrupt.h>
  38 #include <linux/list.h>
  39 #include <linux/spinlock.h>
  40 #include <linux/slab.h>
  41 #include <asm/io.h>
  42 #include <acpi/acpi_bus.h>
  43 #include <acpi/acpi_drivers.h>
  44 #include <linux/dmi.h>
  45
  46 #include "internal.h"
  47
  48 #define ACPI_EC_CLASS                   "embedded_controller"
  49 #define ACPI_EC_DEVICE_NAME             "Embedded Controller"
  50 #define ACPI_EC_FILE_INFO               "info"
  51
  52 #undef PREFIX
  53 #define PREFIX                          "ACPI: EC: "
  54
  55 /* EC status register */
  56 #define ACPI_EC_FLAG_OBF        0x01    /* Output buffer full */
  57 #define ACPI_EC_FLAG_IBF        0x02    /* Input buffer full */
  58 #define ACPI_EC_FLAG_BURST      0x10    /* burst mode */
  59 #define ACPI_EC_FLAG_SCI        0x20    /* EC-SCI occurred */
  60
  61 /* EC commands */
  62 enum ec_command {
  63         ACPI_EC_COMMAND_READ = 0x80,
  64         ACPI_EC_COMMAND_WRITE = 0x81,
  65         ACPI_EC_BURST_ENABLE = 0x82,
  66         ACPI_EC_BURST_DISABLE = 0x83,
  67         ACPI_EC_COMMAND_QUERY = 0x84,
  68 };
  69
  70 #define ACPI_EC_DELAY           500     /* Wait 500ms max. during EC ops */
  71 #define ACPI_EC_UDELAY_GLK      1000    /* Wait 1ms max. to get global lock */
  72 #define ACPI_EC_MSI_UDELAY      550     /* Wait 550us for MSI EC */
  73
  74 enum {
  75         EC_FLAGS_QUERY_PENDING,         /* Query is pending */
  76         EC_FLAGS_GPE_STORM,             /* GPE storm detected */
  77         EC_FLAGS_HANDLERS_INSTALLED,    /* Handlers for GPE and
  78                                          * OpReg are installed */
  79         EC_FLAGS_BLOCKED,               /* Transactions are blocked */
  80 };
  81
  82 /* ec.c is compiled in acpi namespace so this shows up as acpi.ec_delay param */
  83 static unsigned int ec_delay __read_mostly = ACPI_EC_DELAY;
  84 module_param(ec_delay, uint, 0644);
  85 MODULE_PARM_DESC(ec_delay, "Timeout(ms) waited until an EC command completes");
  86
  87 /*
  88  * If the number of false interrupts per one transaction exceeds
  89  * this threshold, will think there is a GPE storm happened and
  90  * will disable the GPE for normal transaction.
  91  */
  92 static unsigned int ec_storm_threshold  __read_mostly = 8;
  93 module_param(ec_storm_threshold, uint, 0644);
  94 MODULE_PARM_DESC(ec_storm_threshold, "Maxim false GPE numbers not considered as GPE storm");
  95
  96 /* If we find an EC via the ECDT, we need to keep a ptr to its context */
  97 /* External interfaces use first EC only, so remember */
  98 typedef int (*acpi_ec_query_func) (void *data);
  99
 100 struct acpi_ec_query_handler {
 101         struct list_head node;
 102         acpi_ec_query_func func;
 103         acpi_handle handle;
 104         void *data;
 105         u8 query_bit;
 106 };
 107
 108 struct transaction {
 109         const u8 *wdata;
 110         u8 *rdata;
 111         unsigned short irq_count;
 112         u8 command;
 113         u8 wi;
 114         u8 ri;
 115         u8 wlen;
 116         u8 rlen;
 117         bool done;
 118 };
 119
 120 struct acpi_ec *boot_ec, *first_ec;
 121 EXPORT_SYMBOL(first_ec);
 122
 123 static int EC_FLAGS_MSI; /* Out-of-spec MSI controller */
 124 static int EC_FLAGS_VALIDATE_ECDT; /* ASUStec ECDTs need to be validated */
 125 static int EC_FLAGS_SKIP_DSDT_SCAN; /* Not all BIOS survive early DSDT scan */
 126
 127 /* --------------------------------------------------------------------------
 128                              Transaction Management
 129    -------------------------------------------------------------------------- */
 130
 131 static inline u8 acpi_ec_read_status(struct acpi_ec *ec)
 132 {
 133         u8 x = inb(ec->command_addr);
 134         pr_debug(PREFIX "---> status = 0x%2.2x\n", x);
 135         return x;
 136 }
 137
 138 static inline u8 acpi_ec_read_data(struct acpi_ec *ec)
 139 {
 140         u8 x = inb(ec->data_addr);
 141         pr_debug(PREFIX "---> data = 0x%2.2x\n", x);
 142         return x;
 143 }
 144
 145 static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command)
 146 {
 147         pr_debug(PREFIX "<--- command = 0x%2.2x\n", command);
 148         outb(command, ec->command_addr);
 149 }
 150
 151 static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data)
 152 {
 153         pr_debug(PREFIX "<--- data = 0x%2.2x\n", data);
 154         outb(data, ec->data_addr);
 155 }
 156
 157 static int ec_transaction_done(struct acpi_ec *ec)
 158 {
 159         unsigned long flags;
 160         int ret = 0;
 161         spin_lock_irqsave(&ec->curr_lock, flags);
 162         if (!ec->curr || ec->curr->done)
 163                 ret = 1;
 164         spin_unlock_irqrestore(&ec->curr_lock, flags);
 165         return ret;
 166 }
 167
 168 static void start_transaction(struct acpi_ec *ec)
 169 {
 170         ec->curr->irq_count = ec->curr->wi = ec->curr->ri = 0;
 171         ec->curr->done = false;
 172         acpi_ec_write_cmd(ec, ec->curr->command);
 173 }
 174
 175 static void advance_transaction(struct acpi_ec *ec, u8 status)
 176 {
 177         unsigned long flags;
 178         spin_lock_irqsave(&ec->curr_lock, flags);
 179         if (!ec->curr)
 180                 goto unlock;
 181         if (ec->curr->wlen > ec->curr->wi) {
 182                 if ((status & ACPI_EC_FLAG_IBF) == 0)
 183                         acpi_ec_write_data(ec,
 184                                 ec->curr->wdata[ec->curr->wi++]);
 185                 else
 186                         goto err;
 187         } else if (ec->curr->rlen > ec->curr->ri) {
 188                 if ((status & ACPI_EC_FLAG_OBF) == 1) {
 189                         ec->curr->rdata[ec->curr->ri++] = acpi_ec_read_data(ec);
 190                         if (ec->curr->rlen == ec->curr->ri)
 191                                 ec->curr->done = true;
 192                 } else
 193                         goto err;
 194         } else if (ec->curr->wlen == ec->curr->wi &&
 195                    (status & ACPI_EC_FLAG_IBF) == 0)
 196                 ec->curr->done = true;
 197         goto unlock;
 198 err:
 199         /* false interrupt, state didn't change */
 200         if (in_interrupt())
 201                 ++ec->curr->irq_count;
 202 unlock:
 203         spin_unlock_irqrestore(&ec->curr_lock, flags);
 204 }
 205
 206 static int acpi_ec_sync_query(struct acpi_ec *ec);
 207
 208 static int ec_check_sci_sync(struct acpi_ec *ec, u8 state)
 209 {
 210         if (state & ACPI_EC_FLAG_SCI) {
 211                 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags))
 212                         return acpi_ec_sync_query(ec);
 213         }
 214         return 0;
 215 }
 216
 217 static int ec_poll(struct acpi_ec *ec)
 218 {
 219         unsigned long flags;
 220         int repeat = 2; /* number of command restarts */
 221         while (repeat--) {
 222                 unsigned long delay = jiffies +
 223                         msecs_to_jiffies(ec_delay);
 224                 do {
 225                         /* don't sleep with disabled interrupts */
 226                         if (EC_FLAGS_MSI || irqs_disabled()) {
 227                                 udelay(ACPI_EC_MSI_UDELAY);
 228                                 if (ec_transaction_done(ec))
 229                                         return 0;
 230                         } else {
 231                                 if (wait_event_timeout(ec->wait,
 232                                                 ec_transaction_done(ec),
 233                                                 msecs_to_jiffies(1)))
 234                                         return 0;
 235                         }
 236                         advance_transaction(ec, acpi_ec_read_status(ec));
 237                 } while (time_before(jiffies, delay));
 238                 if (acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF)
 239                         break;
 240                 pr_debug(PREFIX "controller reset, restart transaction\n");
 241                 spin_lock_irqsave(&ec->curr_lock, flags);
 242                 start_transaction(ec);
 243                 spin_unlock_irqrestore(&ec->curr_lock, flags);
 244         }
 245         return -ETIME;
 246 }
 247
 248 static int acpi_ec_transaction_unlocked(struct acpi_ec *ec,
 249                                         struct transaction *t)
 250 {
 251         unsigned long tmp;
 252         int ret = 0;
 253         if (EC_FLAGS_MSI)
 254                 udelay(ACPI_EC_MSI_UDELAY);
 255         /* start transaction */
 256         spin_lock_irqsave(&ec->curr_lock, tmp);
 257         /* following two actions should be kept atomic */
 258         ec->curr = t;
 259         start_transaction(ec);
 260         if (ec->curr->command == ACPI_EC_COMMAND_QUERY)
 261                 clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
 262         spin_unlock_irqrestore(&ec->curr_lock, tmp);
 263         ret = ec_poll(ec);
 264         spin_lock_irqsave(&ec->curr_lock, tmp);
 265         ec->curr = NULL;
 266         spin_unlock_irqrestore(&ec->curr_lock, tmp);
 267         return ret;
 268 }
 269
 270 static int ec_check_ibf0(struct acpi_ec *ec)
 271 {
 272         u8 status = acpi_ec_read_status(ec);
 273         return (status & ACPI_EC_FLAG_IBF) == 0;
 274 }
 275
 276 static int ec_wait_ibf0(struct acpi_ec *ec)
 277 {
 278         unsigned long delay = jiffies + msecs_to_jiffies(ec_delay);
 279         /* interrupt wait manually if GPE mode is not active */
 280         while (time_before(jiffies, delay))
 281                 if (wait_event_timeout(ec->wait, ec_check_ibf0(ec),
 282                                         msecs_to_jiffies(1)))
 283                         return 0;
 284         return -ETIME;
 285 }
 286
 287 static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t)
 288 {
 289         int status;
 290         u32 glk;
 291         if (!ec || (!t) || (t->wlen && !t->wdata) || (t->rlen && !t->rdata))
 292                 return -EINVAL;
 293         if (t->rdata)
 294                 memset(t->rdata, 0, t->rlen);
 295         mutex_lock(&ec->lock);
 296         if (test_bit(EC_FLAGS_BLOCKED, &ec->flags)) {
 297                 status = -EINVAL;
 298                 goto unlock;
 299         }
 300         if (ec->global_lock) {
 301                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 302                 if (ACPI_FAILURE(status)) {
 303                         status = -ENODEV;
 304                         goto unlock;
 305                 }
 306         }
 307         if (ec_wait_ibf0(ec)) {
 308                 pr_err(PREFIX "input buffer is not empty, "
 309                                 "aborting transaction\n");
 310                 status = -ETIME;
 311                 goto end;
 312         }
 313         pr_debug(PREFIX "transaction start\n");
 314         /* disable GPE during transaction if storm is detected */
 315         if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
 316                 /* It has to be disabled, so that it doesn't trigger. */
 317                 acpi_disable_gpe(NULL, ec->gpe);
 318         }
 319
 320         status = acpi_ec_transaction_unlocked(ec, t);
 321
 322         /* check if we received SCI during transaction */
 323         ec_check_sci_sync(ec, acpi_ec_read_status(ec));
 324         if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
 325                 msleep(1);
 326                 /* It is safe to enable the GPE outside of the transaction. */
 327                 acpi_enable_gpe(NULL, ec->gpe);
 328         } else if (t->irq_count > ec_storm_threshold) {
 329                 pr_info(PREFIX "GPE storm detected, "
 330                         "transactions will use polling mode\n");
 331                 set_bit(EC_FLAGS_GPE_STORM, &ec->flags);
 332         }
 333         pr_debug(PREFIX "transaction end\n");
 334 end:
 335         if (ec->global_lock)
 336                 acpi_release_global_lock(glk);
 337 unlock:
 338         mutex_unlock(&ec->lock);
 339         return status;
 340 }
 341
 342 static int acpi_ec_burst_enable(struct acpi_ec *ec)
 343 {
 344         u8 d;
 345         struct transaction t = {.command = ACPI_EC_BURST_ENABLE,
 346                                 .wdata = NULL, .rdata = &d,
 347                                 .wlen = 0, .rlen = 1};
 348
 349         return acpi_ec_transaction(ec, &t);
 350 }
 351
 352 static int acpi_ec_burst_disable(struct acpi_ec *ec)
 353 {
 354         struct transaction t = {.command = ACPI_EC_BURST_DISABLE,
 355                                 .wdata = NULL, .rdata = NULL,
 356                                 .wlen = 0, .rlen = 0};
 357
 358         return (acpi_ec_read_status(ec) & ACPI_EC_FLAG_BURST) ?
 359                                 acpi_ec_transaction(ec, &t) : 0;
 360 }
 361
 362 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 * data)
 363 {
 364         int result;
 365         u8 d;
 366         struct transaction t = {.command = ACPI_EC_COMMAND_READ,
 367                                 .wdata = &address, .rdata = &d,
 368                                 .wlen = 1, .rlen = 1};
 369
 370         result = acpi_ec_transaction(ec, &t);
 371         *data = d;
 372         return result;
 373 }
 374
 375 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
 376 {
 377         u8 wdata[2] = { address, data };
 378         struct transaction t = {.command = ACPI_EC_COMMAND_WRITE,
 379                                 .wdata = wdata, .rdata = NULL,
 380                                 .wlen = 2, .rlen = 0};
 381
 382         return acpi_ec_transaction(ec, &t);
 383 }
 384
 385 /*
 386  * Externally callable EC access functions. For now, assume 1 EC only
 387  */
 388 int ec_burst_enable(void)
 389 {
 390         if (!first_ec)
 391                 return -ENODEV;
 392         return acpi_ec_burst_enable(first_ec);
 393 }
 394
 395 EXPORT_SYMBOL(ec_burst_enable);
 396
 397 int ec_burst_disable(void)
 398 {
 399         if (!first_ec)
 400                 return -ENODEV;
 401         return acpi_ec_burst_disable(first_ec);
 402 }
 403
 404 EXPORT_SYMBOL(ec_burst_disable);
 405
 406 int ec_read(u8 addr, u8 * val)
 407 {
 408         int err;
 409         u8 temp_data;
 410
 411         if (!first_ec)
 412                 return -ENODEV;
 413
 414         err = acpi_ec_read(first_ec, addr, &temp_data);
 415
 416         if (!err) {
 417                 *val = temp_data;
 418                 return 0;
 419         } else
 420                 return err;
 421 }
 422
 423 EXPORT_SYMBOL(ec_read);
 424
 425 int ec_write(u8 addr, u8 val)
 426 {
 427         int err;
 428
 429         if (!first_ec)
 430                 return -ENODEV;
 431
 432         err = acpi_ec_write(first_ec, addr, val);
 433
 434         return err;
 435 }
 436
 437 EXPORT_SYMBOL(ec_write);
 438
 439 int ec_transaction(u8 command,
 440                    const u8 * wdata, unsigned wdata_len,
 441                    u8 * rdata, unsigned rdata_len)
 442 {
 443         struct transaction t = {.command = command,
 444                                 .wdata = wdata, .rdata = rdata,
 445                                 .wlen = wdata_len, .rlen = rdata_len};
 446         if (!first_ec)
 447                 return -ENODEV;
 448
 449         return acpi_ec_transaction(first_ec, &t);
 450 }
 451
 452 EXPORT_SYMBOL(ec_transaction);
 453
 454 /* Get the handle to the EC device */
 455 acpi_handle ec_get_handle(void)
 456 {
 457         if (!first_ec)
 458                 return NULL;
 459         return first_ec->handle;
 460 }
 461
 462 EXPORT_SYMBOL(ec_get_handle);
 463
 464 void acpi_ec_block_transactions(void)
 465 {
 466         struct acpi_ec *ec = first_ec;
 467
 468         if (!ec)
 469                 return;
 470
 471         mutex_lock(&ec->lock);
 472         /* Prevent transactions from being carried out */
 473         set_bit(EC_FLAGS_BLOCKED, &ec->flags);
 474         mutex_unlock(&ec->lock);
 475 }
 476
 477 void acpi_ec_unblock_transactions(void)
 478 {
 479         struct acpi_ec *ec = first_ec;
 480
 481         if (!ec)
 482                 return;
 483
 484         mutex_lock(&ec->lock);
 485         /* Allow transactions to be carried out again */
 486         clear_bit(EC_FLAGS_BLOCKED, &ec->flags);
 487         mutex_unlock(&ec->lock);
 488 }
 489
 490 void acpi_ec_unblock_transactions_early(void)
 491 {
 492         /*
 493          * Allow transactions to happen again (this function is called from
 494          * atomic context during wakeup, so we don't need to acquire the mutex).
 495          */
 496         if (first_ec)
 497                 clear_bit(EC_FLAGS_BLOCKED, &first_ec->flags);
 498 }
 499
 500 static int acpi_ec_query_unlocked(struct acpi_ec *ec, u8 * data)
 501 {
 502         int result;
 503         u8 d;
 504         struct transaction t = {.command = ACPI_EC_COMMAND_QUERY,
 505                                 .wdata = NULL, .rdata = &d,
 506                                 .wlen = 0, .rlen = 1};
 507         if (!ec || !data)
 508                 return -EINVAL;
 509         /*
 510          * Query the EC to find out which _Qxx method we need to evaluate.
 511          * Note that successful completion of the query causes the ACPI_EC_SCI
 512          * bit to be cleared (and thus clearing the interrupt source).
 513          */
 514         result = acpi_ec_transaction_unlocked(ec, &t);
 515         if (result)
 516                 return result;
 517         if (!d)
 518                 return -ENODATA;
 519         *data = d;
 520         return 0;
 521 }
 522
 523 /* --------------------------------------------------------------------------
 524                                 Event Management
 525    -------------------------------------------------------------------------- */
 526 int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
 527                               acpi_handle handle, acpi_ec_query_func func,
 528                               void *data)
 529 {
 530         struct acpi_ec_query_handler *handler =
 531             kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL);
 532         if (!handler)
 533                 return -ENOMEM;
 534
 535         handler->query_bit = query_bit;
 536         handler->handle = handle;
 537         handler->func = func;
 538         handler->data = data;
 539         mutex_lock(&ec->lock);
 540         list_add(&handler->node, &ec->list);
 541         mutex_unlock(&ec->lock);
 542         return 0;
 543 }
 544
 545 EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler);
 546
 547 void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit)
 548 {
 549         struct acpi_ec_query_handler *handler, *tmp;
 550         mutex_lock(&ec->lock);
 551         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
 552                 if (query_bit == handler->query_bit) {
 553                         list_del(&handler->node);
 554                         kfree(handler);
 555                 }
 556         }
 557         mutex_unlock(&ec->lock);
 558 }
 559
 560 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler);
 561
 562 static void acpi_ec_run(void *cxt)
 563 {
 564         struct acpi_ec_query_handler *handler = cxt;
 565         if (!handler)
 566                 return;
 567         pr_debug(PREFIX "start query execution\n");
 568         if (handler->func)
 569                 handler->func(handler->data);
 570         else if (handler->handle)
 571                 acpi_evaluate_object(handler->handle, NULL, NULL, NULL);
 572         pr_debug(PREFIX "stop query execution\n");
 573         kfree(handler);
 574 }
 575
 576 static int acpi_ec_sync_query(struct acpi_ec *ec)
 577 {
 578         u8 value = 0;
 579         int status;
 580         struct acpi_ec_query_handler *handler, *copy;
 581         if ((status = acpi_ec_query_unlocked(ec, &value)))
 582                 return status;
 583         list_for_each_entry(handler, &ec->list, node) {
 584                 if (value == handler->query_bit) {
 585                         /* have custom handler for this bit */
 586                         copy = kmalloc(sizeof(*handler), GFP_KERNEL);
 587                         if (!copy)
 588                                 return -ENOMEM;
 589                         memcpy(copy, handler, sizeof(*copy));
 590                         pr_debug(PREFIX "push query execution (0x%2x) on queue\n", value);
 591                         return acpi_os_execute((copy->func) ?
 592                                 OSL_NOTIFY_HANDLER : OSL_GPE_HANDLER,
 593                                 acpi_ec_run, copy);
 594                 }
 595         }
 596         return 0;
 597 }
 598
 599 static void acpi_ec_gpe_query(void *ec_cxt)
 600 {
 601         struct acpi_ec *ec = ec_cxt;
 602         if (!ec)
 603                 return;
 604         mutex_lock(&ec->lock);
 605         acpi_ec_sync_query(ec);
 606         mutex_unlock(&ec->lock);
 607 }
 608
 609 static int ec_check_sci(struct acpi_ec *ec, u8 state)
 610 {
 611         if (state & ACPI_EC_FLAG_SCI) {
 612                 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) {
 613                         pr_debug(PREFIX "push gpe query to the queue\n");
 614                         return acpi_os_execute(OSL_NOTIFY_HANDLER,
 615                                 acpi_ec_gpe_query, ec);
 616                 }
 617         }
 618         return 0;
 619 }
 620
 621 static u32 acpi_ec_gpe_handler(acpi_handle gpe_device,
 622         u32 gpe_number, void *data)
 623 {
 624         struct acpi_ec *ec = data;
 625
 626         pr_debug(PREFIX "~~~> interrupt\n");
 627
 628         advance_transaction(ec, acpi_ec_read_status(ec));
 629         if (ec_transaction_done(ec) &&
 630             (acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF) == 0) {
 631                 wake_up(&ec->wait);
 632                 ec_check_sci(ec, acpi_ec_read_status(ec));
 633         }
 634         return ACPI_INTERRUPT_HANDLED | ACPI_REENABLE_GPE;
 635 }
 636
 637 /* --------------------------------------------------------------------------
 638                              Address Space Management
 639    -------------------------------------------------------------------------- */
 640
 641 static acpi_status
 642 acpi_ec_space_handler(u32 function, acpi_physical_address address,
 643                       u32 bits, u64 *value64,
 644                       void *handler_context, void *region_context)
 645 {
 646         struct acpi_ec *ec = handler_context;
 647         int result = 0, i, bytes = bits / 8;
 648         u8 *value = (u8 *)value64;
 649
 650         if ((address > 0xFF) || !value || !handler_context)
 651                 return AE_BAD_PARAMETER;
 652
 653         if (function != ACPI_READ && function != ACPI_WRITE)
 654                 return AE_BAD_PARAMETER;
 655
 656         if (EC_FLAGS_MSI || bits > 8)
 657                 acpi_ec_burst_enable(ec);
 658
 659         for (i = 0; i < bytes; ++i, ++address, ++value)
 660                 result = (function == ACPI_READ) ?
 661                         acpi_ec_read(ec, address, value) :
 662                         acpi_ec_write(ec, address, *value);
 663
 664         if (EC_FLAGS_MSI || bits > 8)
 665                 acpi_ec_burst_disable(ec);
 666
 667         switch (result) {
 668         case -EINVAL:
 669                 return AE_BAD_PARAMETER;
 670                 break;
 671         case -ENODEV:
 672                 return AE_NOT_FOUND;
 673                 break;
 674         case -ETIME:
 675                 return AE_TIME;
 676                 break;
 677         default:
 678                 return AE_OK;
 679         }
 680 }
 681
 682 /* --------------------------------------------------------------------------
 683                                Driver Interface
 684    -------------------------------------------------------------------------- */
 685 static acpi_status
 686 ec_parse_io_ports(struct acpi_resource *resource, void *context);
 687
 688 static struct acpi_ec *make_acpi_ec(void)
 689 {
 690         struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
 691         if (!ec)
 692                 return NULL;
 693         ec->flags = 1 << EC_FLAGS_QUERY_PENDING;
 694         mutex_init(&ec->lock);
 695         init_waitqueue_head(&ec->wait);
 696         INIT_LIST_HEAD(&ec->list);
 697         spin_lock_init(&ec->curr_lock);
 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         char node_name[5];
 706         struct acpi_buffer buffer = { sizeof(node_name), node_name };
 707         struct acpi_ec *ec = context;
 708         int value = 0;
 709         acpi_status status;
 710
 711         status = acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
 712
 713         if (ACPI_SUCCESS(status) && sscanf(node_name, "_Q%x", &value) == 1) {
 714                 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL);
 715         }
 716         return AE_OK;
 717 }
 718
 719 static acpi_status
 720 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
 721 {
 722         acpi_status status;
 723         unsigned long long tmp = 0;
 724
 725         struct acpi_ec *ec = context;
 726
 727         /* clear addr values, ec_parse_io_ports depend on it */
 728         ec->command_addr = ec->data_addr = 0;
 729
 730         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
 731                                      ec_parse_io_ports, ec);
 732         if (ACPI_FAILURE(status))
 733                 return status;
 734
 735         /* Get GPE bit assignment (EC events). */
 736         /* TODO: Add support for _GPE returning a package */
 737         status = acpi_evaluate_integer(handle, "_GPE", NULL, &tmp);
 738         if (ACPI_FAILURE(status))
 739                 return status;
 740         ec->gpe = tmp;
 741         /* Use the global lock for all EC transactions? */
 742         tmp = 0;
 743         acpi_evaluate_integer(handle, "_GLK", NULL, &tmp);
 744         ec->global_lock = tmp;
 745         ec->handle = handle;
 746         return AE_CTRL_TERMINATE;
 747 }
 748
 749 static int ec_install_handlers(struct acpi_ec *ec)
 750 {
 751         acpi_status status;
 752         if (test_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags))
 753                 return 0;
 754         status = acpi_install_gpe_handler(NULL, ec->gpe,
 755                                   ACPI_GPE_EDGE_TRIGGERED,
 756                                   &acpi_ec_gpe_handler, ec);
 757         if (ACPI_FAILURE(status))
 758                 return -ENODEV;
 759
 760         acpi_enable_gpe(NULL, ec->gpe);
 761         status = acpi_install_address_space_handler(ec->handle,
 762                                                     ACPI_ADR_SPACE_EC,
 763                                                     &acpi_ec_space_handler,
 764                                                     NULL, ec);
 765         if (ACPI_FAILURE(status)) {
 766                 if (status == AE_NOT_FOUND) {
 767                         /*
 768                          * Maybe OS fails in evaluating the _REG object.
 769                          * The AE_NOT_FOUND error will be ignored and OS
 770                          * continue to initialize EC.
 771                          */
 772                         printk(KERN_ERR "Fail in evaluating the _REG object"
 773                                 " of EC device. Broken bios is suspected.\n");
 774                 } else {
 775                         acpi_remove_gpe_handler(NULL, ec->gpe,
 776                                 &acpi_ec_gpe_handler);
 777                         acpi_disable_gpe(NULL, ec->gpe);
 778                         return -ENODEV;
 779                 }
 780         }
 781
 782         set_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
 783         return 0;
 784 }
 785
 786 static void ec_remove_handlers(struct acpi_ec *ec)
 787 {
 788         acpi_disable_gpe(NULL, ec->gpe);
 789         if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle,
 790                                 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler)))
 791                 pr_err(PREFIX "failed to remove space handler\n");
 792         if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe,
 793                                 &acpi_ec_gpe_handler)))
 794                 pr_err(PREFIX "failed to remove gpe handler\n");
 795         clear_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
 796 }
 797
 798 static int acpi_ec_add(struct acpi_device *device)
 799 {
 800         struct acpi_ec *ec = NULL;
 801         int ret;
 802
 803         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
 804         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
 805
 806         /* Check for boot EC */
 807         if (boot_ec &&
 808             (boot_ec->handle == device->handle ||
 809              boot_ec->handle == ACPI_ROOT_OBJECT)) {
 810                 ec = boot_ec;
 811                 boot_ec = NULL;
 812         } else {
 813                 ec = make_acpi_ec();
 814                 if (!ec)
 815                         return -ENOMEM;
 816         }
 817         if (ec_parse_device(device->handle, 0, ec, NULL) !=
 818                 AE_CTRL_TERMINATE) {
 819                         kfree(ec);
 820                         return -EINVAL;
 821         }
 822
 823         /* Find and register all query methods */
 824         acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1,
 825                             acpi_ec_register_query_methods, NULL, ec, NULL);
 826
 827         if (!first_ec)
 828                 first_ec = ec;
 829         device->driver_data = ec;
 830
 831         ret = !!request_region(ec->data_addr, 1, "EC data");
 832         WARN(!ret, "Could not request EC data io port 0x%lx", ec->data_addr);
 833         ret = !!request_region(ec->command_addr, 1, "EC cmd");
 834         WARN(!ret, "Could not request EC cmd io port 0x%lx", ec->command_addr);
 835
 836         pr_info(PREFIX "GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n",
 837                           ec->gpe, ec->command_addr, ec->data_addr);
 838
 839         ret = ec_install_handlers(ec);
 840
 841         /* EC is fully operational, allow queries */
 842         clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
 843         return ret;
 844 }
 845
 846 static int acpi_ec_remove(struct acpi_device *device, int type)
 847 {
 848         struct acpi_ec *ec;
 849         struct acpi_ec_query_handler *handler, *tmp;
 850
 851         if (!device)
 852                 return -EINVAL;
 853
 854         ec = acpi_driver_data(device);
 855         ec_remove_handlers(ec);
 856         mutex_lock(&ec->lock);
 857         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
 858                 list_del(&handler->node);
 859                 kfree(handler);
 860         }
 861         mutex_unlock(&ec->lock);
 862         release_region(ec->data_addr, 1);
 863         release_region(ec->command_addr, 1);
 864         device->driver_data = NULL;
 865         if (ec == first_ec)
 866                 first_ec = NULL;
 867         kfree(ec);
 868         return 0;
 869 }
 870
 871 static acpi_status
 872 ec_parse_io_ports(struct acpi_resource *resource, void *context)
 873 {
 874         struct acpi_ec *ec = context;
 875
 876         if (resource->type != ACPI_RESOURCE_TYPE_IO)
 877                 return AE_OK;
 878
 879         /*
 880          * The first address region returned is the data port, and
 881          * the second address region returned is the status/command
 882          * port.
 883          */
 884         if (ec->data_addr == 0)
 885                 ec->data_addr = resource->data.io.minimum;
 886         else if (ec->command_addr == 0)
 887                 ec->command_addr = resource->data.io.minimum;
 888         else
 889                 return AE_CTRL_TERMINATE;
 890
 891         return AE_OK;
 892 }
 893
 894 int __init acpi_boot_ec_enable(void)
 895 {
 896         if (!boot_ec || test_bit(EC_FLAGS_HANDLERS_INSTALLED, &boot_ec->flags))
 897                 return 0;
 898         if (!ec_install_handlers(boot_ec)) {
 899                 first_ec = boot_ec;
 900                 return 0;
 901         }
 902         return -EFAULT;
 903 }
 904
 905 static const struct acpi_device_id ec_device_ids[] = {
 906         {"PNP0C09", 0},
 907         {"", 0},
 908 };
 909
 910 /* Some BIOS do not survive early DSDT scan, skip it */
 911 static int ec_skip_dsdt_scan(const struct dmi_system_id *id)
 912 {
 913         EC_FLAGS_SKIP_DSDT_SCAN = 1;
 914         return 0;
 915 }
 916
 917 /* ASUStek often supplies us with broken ECDT, validate it */
 918 static int ec_validate_ecdt(const struct dmi_system_id *id)
 919 {
 920         EC_FLAGS_VALIDATE_ECDT = 1;
 921         return 0;
 922 }
 923
 924 /* MSI EC needs special treatment, enable it */
 925 static int ec_flag_msi(const struct dmi_system_id *id)
 926 {
 927         printk(KERN_DEBUG PREFIX "Detected MSI hardware, enabling workarounds.\n");
 928         EC_FLAGS_MSI = 1;
 929         EC_FLAGS_VALIDATE_ECDT = 1;
 930         return 0;
 931 }
 932
 933 /*
 934  * Clevo M720 notebook actually works ok with IRQ mode, if we lifted
 935  * the GPE storm threshold back to 20
 936  */
 937 static int ec_enlarge_storm_threshold(const struct dmi_system_id *id)
 938 {
 939         pr_debug("Setting the EC GPE storm threshold to 20\n");
 940         ec_storm_threshold  = 20;
 941         return 0;
 942 }
 943
 944 static struct dmi_system_id __initdata ec_dmi_table[] = {
 945         {
 946         ec_skip_dsdt_scan, "Compal JFL92", {
 947         DMI_MATCH(DMI_BIOS_VENDOR, "COMPAL"),
 948         DMI_MATCH(DMI_BOARD_NAME, "JFL92") }, NULL},
 949         {
 950         ec_flag_msi, "MSI hardware", {
 951         DMI_MATCH(DMI_BIOS_VENDOR, "Micro-Star")}, NULL},
 952         {
 953         ec_flag_msi, "MSI hardware", {
 954         DMI_MATCH(DMI_SYS_VENDOR, "Micro-Star")}, NULL},
 955         {
 956         ec_flag_msi, "MSI hardware", {
 957         DMI_MATCH(DMI_CHASSIS_VENDOR, "MICRO-Star")}, NULL},
 958         {
 959         ec_flag_msi, "MSI hardware", {
 960         DMI_MATCH(DMI_CHASSIS_VENDOR, "MICRO-STAR")}, NULL},
 961         {
 962         ec_flag_msi, "Quanta hardware", {
 963         DMI_MATCH(DMI_SYS_VENDOR, "Quanta"),
 964         DMI_MATCH(DMI_PRODUCT_NAME, "TW8/SW8/DW8"),}, NULL},
 965         {
 966         ec_flag_msi, "Quanta hardware", {
 967         DMI_MATCH(DMI_SYS_VENDOR, "Quanta"),
 968         DMI_MATCH(DMI_PRODUCT_NAME, "TW9/SW9"),}, NULL},
 969         {
 970         ec_validate_ecdt, "ASUS hardware", {
 971         DMI_MATCH(DMI_BIOS_VENDOR, "ASUS") }, NULL},
 972         {
 973         ec_validate_ecdt, "ASUS hardware", {
 974         DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer Inc.") }, NULL},
 975         {
 976         ec_enlarge_storm_threshold, "CLEVO hardware", {
 977         DMI_MATCH(DMI_SYS_VENDOR, "CLEVO Co."),
 978         DMI_MATCH(DMI_PRODUCT_NAME, "M720T/M730T"),}, NULL},
 979         {},
 980 };
 981
 982 int __init acpi_ec_ecdt_probe(void)
 983 {
 984         acpi_status status;
 985         struct acpi_ec *saved_ec = NULL;
 986         struct acpi_table_ecdt *ecdt_ptr;
 987
 988         boot_ec = make_acpi_ec();
 989         if (!boot_ec)
 990                 return -ENOMEM;
 991         /*
 992          * Generate a boot ec context
 993          */
 994         dmi_check_system(ec_dmi_table);
 995         status = acpi_get_table(ACPI_SIG_ECDT, 1,
 996                                 (struct acpi_table_header **)&ecdt_ptr);
 997         if (ACPI_SUCCESS(status)) {
 998                 pr_info(PREFIX "EC description table is found, configuring boot EC\n");
 999                 boot_ec->command_addr = ecdt_ptr->control.address;
1000                 boot_ec->data_addr = ecdt_ptr->data.address;
1001                 boot_ec->gpe = ecdt_ptr->gpe;
1002                 boot_ec->handle = ACPI_ROOT_OBJECT;
1003                 acpi_get_handle(ACPI_ROOT_OBJECT, ecdt_ptr->id, &boot_ec->handle);
1004                 /* Don't trust ECDT, which comes from ASUSTek */
1005                 if (!EC_FLAGS_VALIDATE_ECDT)
1006                         goto install;
1007                 saved_ec = kmemdup(boot_ec, sizeof(struct acpi_ec), GFP_KERNEL);
1008                 if (!saved_ec)
1009                         return -ENOMEM;
1010         /* fall through */
1011         }
1012
1013         if (EC_FLAGS_SKIP_DSDT_SCAN)
1014                 return -ENODEV;
1015
1016         /* This workaround is needed only on some broken machines,
1017          * which require early EC, but fail to provide ECDT */
1018         printk(KERN_DEBUG PREFIX "Look up EC in DSDT\n");
1019         status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device,
1020                                         boot_ec, NULL);
1021         /* Check that acpi_get_devices actually find something */
1022         if (ACPI_FAILURE(status) || !boot_ec->handle)
1023                 goto error;
1024         if (saved_ec) {
1025                 /* try to find good ECDT from ASUSTek */
1026                 if (saved_ec->command_addr != boot_ec->command_addr ||
1027                     saved_ec->data_addr != boot_ec->data_addr ||
1028                     saved_ec->gpe != boot_ec->gpe ||
1029                     saved_ec->handle != boot_ec->handle)
1030                         pr_info(PREFIX "ASUSTek keeps feeding us with broken "
1031                         "ECDT tables, which are very hard to workaround. "
1032                         "Trying to use DSDT EC info instead. Please send "
1033                         "output of acpidump to linux-acpi@vger.kernel.org\n");
1034                 kfree(saved_ec);
1035                 saved_ec = NULL;
1036         } else {
1037                 /* We really need to limit this workaround, the only ASUS,
1038                 * which needs it, has fake EC._INI method, so use it as flag.
1039                 * Keep boot_ec struct as it will be needed soon.
1040                 */
1041                 acpi_handle dummy;
1042                 if (!dmi_name_in_vendors("ASUS") ||
1043                     ACPI_FAILURE(acpi_get_handle(boot_ec->handle, "_INI",
1044                                                         &dummy)))
1045                         return -ENODEV;
1046         }
1047 install:
1048         if (!ec_install_handlers(boot_ec)) {
1049                 first_ec = boot_ec;
1050                 return 0;
1051         }
1052 error:
1053         kfree(boot_ec);
1054         boot_ec = NULL;
1055         return -ENODEV;
1056 }
1057
1058 static struct acpi_driver acpi_ec_driver = {
1059         .name = "ec",
1060         .class = ACPI_EC_CLASS,
1061         .ids = ec_device_ids,
1062         .ops = {
1063                 .add = acpi_ec_add,
1064                 .remove = acpi_ec_remove,
1065                 },
1066 };
1067
1068 int __init acpi_ec_init(void)
1069 {
1070         int result = 0;
1071
1072         /* Now register the driver for the EC */
1073         result = acpi_bus_register_driver(&acpi_ec_driver);
1074         if (result < 0)
1075                 return -ENODEV;
1076
1077         return result;
1078 }
1079
1080 /* EC driver currently not unloadable */
1081 #if 0
1082 static void __exit acpi_ec_exit(void)
1083 {
1084
1085         acpi_bus_unregister_driver(&acpi_ec_driver);
1086         return;
1087 }
1088 #endif  /* 0 */