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 #define ACPI_EC_STORM_THRESHOLD 8       /* number of false interrupts
  75                                            per one transaction */
  76
  77 enum {
  78         EC_FLAGS_QUERY_PENDING,         /* Query is pending */
  79         EC_FLAGS_GPE_STORM,             /* GPE storm detected */
  80         EC_FLAGS_HANDLERS_INSTALLED,    /* Handlers for GPE and
  81                                          * OpReg are installed */
  82         EC_FLAGS_BLOCKED,               /* Transactions are blocked */
  83 };
  84
  85 /* ec.c is compiled in acpi namespace so this shows up as acpi.ec_delay param */
  86 static unsigned int ec_delay __read_mostly = ACPI_EC_DELAY;
  87 module_param(ec_delay, uint, 0644);
  88 MODULE_PARM_DESC(ec_delay, "Timeout(ms) waited until an EC command completes");
  89
  90 /* If we find an EC via the ECDT, we need to keep a ptr to its context */
  91 /* External interfaces use first EC only, so remember */
  92 typedef int (*acpi_ec_query_func) (void *data);
  93
  94 struct acpi_ec_query_handler {
  95         struct list_head node;
  96         acpi_ec_query_func func;
  97         acpi_handle handle;
  98         void *data;
  99         u8 query_bit;
 100 };
 101
 102 struct transaction {
 103         const u8 *wdata;
 104         u8 *rdata;
 105         unsigned short irq_count;
 106         u8 command;
 107         u8 wi;
 108         u8 ri;
 109         u8 wlen;
 110         u8 rlen;
 111         bool done;
 112 };
 113
 114 struct acpi_ec *boot_ec, *first_ec;
 115 EXPORT_SYMBOL(first_ec);
 116
 117 static int EC_FLAGS_MSI; /* Out-of-spec MSI controller */
 118 static int EC_FLAGS_VALIDATE_ECDT; /* ASUStec ECDTs need to be validated */
 119 static int EC_FLAGS_SKIP_DSDT_SCAN; /* Not all BIOS survive early DSDT scan */
 120
 121 /* --------------------------------------------------------------------------
 122                              Transaction Management
 123    -------------------------------------------------------------------------- */
 124
 125 static inline u8 acpi_ec_read_status(struct acpi_ec *ec)
 126 {
 127         u8 x = inb(ec->command_addr);
 128         pr_debug(PREFIX "---> status = 0x%2.2x\n", x);
 129         return x;
 130 }
 131
 132 static inline u8 acpi_ec_read_data(struct acpi_ec *ec)
 133 {
 134         u8 x = inb(ec->data_addr);
 135         pr_debug(PREFIX "---> data = 0x%2.2x\n", x);
 136         return x;
 137 }
 138
 139 static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command)
 140 {
 141         pr_debug(PREFIX "<--- command = 0x%2.2x\n", command);
 142         outb(command, ec->command_addr);
 143 }
 144
 145 static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data)
 146 {
 147         pr_debug(PREFIX "<--- data = 0x%2.2x\n", data);
 148         outb(data, ec->data_addr);
 149 }
 150
 151 static int ec_transaction_done(struct acpi_ec *ec)
 152 {
 153         unsigned long flags;
 154         int ret = 0;
 155         spin_lock_irqsave(&ec->curr_lock, flags);
 156         if (!ec->curr || ec->curr->done)
 157                 ret = 1;
 158         spin_unlock_irqrestore(&ec->curr_lock, flags);
 159         return ret;
 160 }
 161
 162 static void start_transaction(struct acpi_ec *ec)
 163 {
 164         ec->curr->irq_count = ec->curr->wi = ec->curr->ri = 0;
 165         ec->curr->done = false;
 166         acpi_ec_write_cmd(ec, ec->curr->command);
 167 }
 168
 169 static void advance_transaction(struct acpi_ec *ec, u8 status)
 170 {
 171         unsigned long flags;
 172         spin_lock_irqsave(&ec->curr_lock, flags);
 173         if (!ec->curr)
 174                 goto unlock;
 175         if (ec->curr->wlen > ec->curr->wi) {
 176                 if ((status & ACPI_EC_FLAG_IBF) == 0)
 177                         acpi_ec_write_data(ec,
 178                                 ec->curr->wdata[ec->curr->wi++]);
 179                 else
 180                         goto err;
 181         } else if (ec->curr->rlen > ec->curr->ri) {
 182                 if ((status & ACPI_EC_FLAG_OBF) == 1) {
 183                         ec->curr->rdata[ec->curr->ri++] = acpi_ec_read_data(ec);
 184                         if (ec->curr->rlen == ec->curr->ri)
 185                                 ec->curr->done = true;
 186                 } else
 187                         goto err;
 188         } else if (ec->curr->wlen == ec->curr->wi &&
 189                    (status & ACPI_EC_FLAG_IBF) == 0)
 190                 ec->curr->done = true;
 191         goto unlock;
 192 err:
 193         /* false interrupt, state didn't change */
 194         if (in_interrupt())
 195                 ++ec->curr->irq_count;
 196 unlock:
 197         spin_unlock_irqrestore(&ec->curr_lock, flags);
 198 }
 199
 200 static int acpi_ec_sync_query(struct acpi_ec *ec);
 201
 202 static int ec_check_sci_sync(struct acpi_ec *ec, u8 state)
 203 {
 204         if (state & ACPI_EC_FLAG_SCI) {
 205                 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags))
 206                         return acpi_ec_sync_query(ec);
 207         }
 208         return 0;
 209 }
 210
 211 static int ec_poll(struct acpi_ec *ec)
 212 {
 213         unsigned long flags;
 214         int repeat = 2; /* number of command restarts */
 215         while (repeat--) {
 216                 unsigned long delay = jiffies +
 217                         msecs_to_jiffies(ec_delay);
 218                 do {
 219                         /* don't sleep with disabled interrupts */
 220                         if (EC_FLAGS_MSI || irqs_disabled()) {
 221                                 udelay(ACPI_EC_MSI_UDELAY);
 222                                 if (ec_transaction_done(ec))
 223                                         return 0;
 224                         } else {
 225                                 if (wait_event_timeout(ec->wait,
 226                                                 ec_transaction_done(ec),
 227                                                 msecs_to_jiffies(1)))
 228                                         return 0;
 229                         }
 230                         advance_transaction(ec, acpi_ec_read_status(ec));
 231                 } while (time_before(jiffies, delay));
 232                 if (acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF)
 233                         break;
 234                 pr_debug(PREFIX "controller reset, restart transaction\n");
 235                 spin_lock_irqsave(&ec->curr_lock, flags);
 236                 start_transaction(ec);
 237                 spin_unlock_irqrestore(&ec->curr_lock, flags);
 238         }
 239         return -ETIME;
 240 }
 241
 242 static int acpi_ec_transaction_unlocked(struct acpi_ec *ec,
 243                                         struct transaction *t)
 244 {
 245         unsigned long tmp;
 246         int ret = 0;
 247         if (EC_FLAGS_MSI)
 248                 udelay(ACPI_EC_MSI_UDELAY);
 249         /* start transaction */
 250         spin_lock_irqsave(&ec->curr_lock, tmp);
 251         /* following two actions should be kept atomic */
 252         ec->curr = t;
 253         start_transaction(ec);
 254         if (ec->curr->command == ACPI_EC_COMMAND_QUERY)
 255                 clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
 256         spin_unlock_irqrestore(&ec->curr_lock, tmp);
 257         ret = ec_poll(ec);
 258         spin_lock_irqsave(&ec->curr_lock, tmp);
 259         ec->curr = NULL;
 260         spin_unlock_irqrestore(&ec->curr_lock, tmp);
 261         return ret;
 262 }
 263
 264 static int ec_check_ibf0(struct acpi_ec *ec)
 265 {
 266         u8 status = acpi_ec_read_status(ec);
 267         return (status & ACPI_EC_FLAG_IBF) == 0;
 268 }
 269
 270 static int ec_wait_ibf0(struct acpi_ec *ec)
 271 {
 272         unsigned long delay = jiffies + msecs_to_jiffies(ec_delay);
 273         /* interrupt wait manually if GPE mode is not active */
 274         while (time_before(jiffies, delay))
 275                 if (wait_event_timeout(ec->wait, ec_check_ibf0(ec),
 276                                         msecs_to_jiffies(1)))
 277                         return 0;
 278         return -ETIME;
 279 }
 280
 281 static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t)
 282 {
 283         int status;
 284         u32 glk;
 285         if (!ec || (!t) || (t->wlen && !t->wdata) || (t->rlen && !t->rdata))
 286                 return -EINVAL;
 287         if (t->rdata)
 288                 memset(t->rdata, 0, t->rlen);
 289         mutex_lock(&ec->lock);
 290         if (test_bit(EC_FLAGS_BLOCKED, &ec->flags)) {
 291                 status = -EINVAL;
 292                 goto unlock;
 293         }
 294         if (ec->global_lock) {
 295                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 296                 if (ACPI_FAILURE(status)) {
 297                         status = -ENODEV;
 298                         goto unlock;
 299                 }
 300         }
 301         if (ec_wait_ibf0(ec)) {
 302                 pr_err(PREFIX "input buffer is not empty, "
 303                                 "aborting transaction\n");
 304                 status = -ETIME;
 305                 goto end;
 306         }
 307         pr_debug(PREFIX "transaction start\n");
 308         /* disable GPE during transaction if storm is detected */
 309         if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
 310                 /* It has to be disabled, so that it doesn't trigger. */
 311                 acpi_disable_gpe(NULL, ec->gpe);
 312         }
 313
 314         status = acpi_ec_transaction_unlocked(ec, t);
 315
 316         /* check if we received SCI during transaction */
 317         ec_check_sci_sync(ec, acpi_ec_read_status(ec));
 318         if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
 319                 msleep(1);
 320                 /* It is safe to enable the GPE outside of the transaction. */
 321                 acpi_enable_gpe(NULL, ec->gpe);
 322         } else if (t->irq_count > ACPI_EC_STORM_THRESHOLD) {
 323                 pr_info(PREFIX "GPE storm detected, "
 324                         "transactions will use polling mode\n");
 325                 set_bit(EC_FLAGS_GPE_STORM, &ec->flags);
 326         }
 327         pr_debug(PREFIX "transaction end\n");
 328 end:
 329         if (ec->global_lock)
 330                 acpi_release_global_lock(glk);
 331 unlock:
 332         mutex_unlock(&ec->lock);
 333         return status;
 334 }
 335
 336 static int acpi_ec_burst_enable(struct acpi_ec *ec)
 337 {
 338         u8 d;
 339         struct transaction t = {.command = ACPI_EC_BURST_ENABLE,
 340                                 .wdata = NULL, .rdata = &d,
 341                                 .wlen = 0, .rlen = 1};
 342
 343         return acpi_ec_transaction(ec, &t);
 344 }
 345
 346 static int acpi_ec_burst_disable(struct acpi_ec *ec)
 347 {
 348         struct transaction t = {.command = ACPI_EC_BURST_DISABLE,
 349                                 .wdata = NULL, .rdata = NULL,
 350                                 .wlen = 0, .rlen = 0};
 351
 352         return (acpi_ec_read_status(ec) & ACPI_EC_FLAG_BURST) ?
 353                                 acpi_ec_transaction(ec, &t) : 0;
 354 }
 355
 356 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 * data)
 357 {
 358         int result;
 359         u8 d;
 360         struct transaction t = {.command = ACPI_EC_COMMAND_READ,
 361                                 .wdata = &address, .rdata = &d,
 362                                 .wlen = 1, .rlen = 1};
 363
 364         result = acpi_ec_transaction(ec, &t);
 365         *data = d;
 366         return result;
 367 }
 368
 369 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
 370 {
 371         u8 wdata[2] = { address, data };
 372         struct transaction t = {.command = ACPI_EC_COMMAND_WRITE,
 373                                 .wdata = wdata, .rdata = NULL,
 374                                 .wlen = 2, .rlen = 0};
 375
 376         return acpi_ec_transaction(ec, &t);
 377 }
 378
 379 /*
 380  * Externally callable EC access functions. For now, assume 1 EC only
 381  */
 382 int ec_burst_enable(void)
 383 {
 384         if (!first_ec)
 385                 return -ENODEV;
 386         return acpi_ec_burst_enable(first_ec);
 387 }
 388
 389 EXPORT_SYMBOL(ec_burst_enable);
 390
 391 int ec_burst_disable(void)
 392 {
 393         if (!first_ec)
 394                 return -ENODEV;
 395         return acpi_ec_burst_disable(first_ec);
 396 }
 397
 398 EXPORT_SYMBOL(ec_burst_disable);
 399
 400 int ec_read(u8 addr, u8 * val)
 401 {
 402         int err;
 403         u8 temp_data;
 404
 405         if (!first_ec)
 406                 return -ENODEV;
 407
 408         err = acpi_ec_read(first_ec, addr, &temp_data);
 409
 410         if (!err) {
 411                 *val = temp_data;
 412                 return 0;
 413         } else
 414                 return err;
 415 }
 416
 417 EXPORT_SYMBOL(ec_read);
 418
 419 int ec_write(u8 addr, u8 val)
 420 {
 421         int err;
 422
 423         if (!first_ec)
 424                 return -ENODEV;
 425
 426         err = acpi_ec_write(first_ec, addr, val);
 427
 428         return err;
 429 }
 430
 431 EXPORT_SYMBOL(ec_write);
 432
 433 int ec_transaction(u8 command,
 434                    const u8 * wdata, unsigned wdata_len,
 435                    u8 * rdata, unsigned rdata_len)
 436 {
 437         struct transaction t = {.command = command,
 438                                 .wdata = wdata, .rdata = rdata,
 439                                 .wlen = wdata_len, .rlen = rdata_len};
 440         if (!first_ec)
 441                 return -ENODEV;
 442
 443         return acpi_ec_transaction(first_ec, &t);
 444 }
 445
 446 EXPORT_SYMBOL(ec_transaction);
 447
 448 /* Get the handle to the EC device */
 449 acpi_handle ec_get_handle(void)
 450 {
 451         if (!first_ec)
 452                 return NULL;
 453         return first_ec->handle;
 454 }
 455
 456 EXPORT_SYMBOL(ec_get_handle);
 457
 458 void acpi_ec_block_transactions(void)
 459 {
 460         struct acpi_ec *ec = first_ec;
 461
 462         if (!ec)
 463                 return;
 464
 465         mutex_lock(&ec->lock);
 466         /* Prevent transactions from being carried out */
 467         set_bit(EC_FLAGS_BLOCKED, &ec->flags);
 468         mutex_unlock(&ec->lock);
 469 }
 470
 471 void acpi_ec_unblock_transactions(void)
 472 {
 473         struct acpi_ec *ec = first_ec;
 474
 475         if (!ec)
 476                 return;
 477
 478         mutex_lock(&ec->lock);
 479         /* Allow transactions to be carried out again */
 480         clear_bit(EC_FLAGS_BLOCKED, &ec->flags);
 481         mutex_unlock(&ec->lock);
 482 }
 483
 484 void acpi_ec_unblock_transactions_early(void)
 485 {
 486         /*
 487          * Allow transactions to happen again (this function is called from
 488          * atomic context during wakeup, so we don't need to acquire the mutex).
 489          */
 490         if (first_ec)
 491                 clear_bit(EC_FLAGS_BLOCKED, &first_ec->flags);
 492 }
 493
 494 static int acpi_ec_query_unlocked(struct acpi_ec *ec, u8 * data)
 495 {
 496         int result;
 497         u8 d;
 498         struct transaction t = {.command = ACPI_EC_COMMAND_QUERY,
 499                                 .wdata = NULL, .rdata = &d,
 500                                 .wlen = 0, .rlen = 1};
 501         if (!ec || !data)
 502                 return -EINVAL;
 503         /*
 504          * Query the EC to find out which _Qxx method we need to evaluate.
 505          * Note that successful completion of the query causes the ACPI_EC_SCI
 506          * bit to be cleared (and thus clearing the interrupt source).
 507          */
 508         result = acpi_ec_transaction_unlocked(ec, &t);
 509         if (result)
 510                 return result;
 511         if (!d)
 512                 return -ENODATA;
 513         *data = d;
 514         return 0;
 515 }
 516
 517 /* --------------------------------------------------------------------------
 518                                 Event Management
 519    -------------------------------------------------------------------------- */
 520 int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
 521                               acpi_handle handle, acpi_ec_query_func func,
 522                               void *data)
 523 {
 524         struct acpi_ec_query_handler *handler =
 525             kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL);
 526         if (!handler)
 527                 return -ENOMEM;
 528
 529         handler->query_bit = query_bit;
 530         handler->handle = handle;
 531         handler->func = func;
 532         handler->data = data;
 533         mutex_lock(&ec->lock);
 534         list_add(&handler->node, &ec->list);
 535         mutex_unlock(&ec->lock);
 536         return 0;
 537 }
 538
 539 EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler);
 540
 541 void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit)
 542 {
 543         struct acpi_ec_query_handler *handler, *tmp;
 544         mutex_lock(&ec->lock);
 545         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
 546                 if (query_bit == handler->query_bit) {
 547                         list_del(&handler->node);
 548                         kfree(handler);
 549                 }
 550         }
 551         mutex_unlock(&ec->lock);
 552 }
 553
 554 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler);
 555
 556 static void acpi_ec_run(void *cxt)
 557 {
 558         struct acpi_ec_query_handler *handler = cxt;
 559         if (!handler)
 560                 return;
 561         pr_debug(PREFIX "start query execution\n");
 562         if (handler->func)
 563                 handler->func(handler->data);
 564         else if (handler->handle)
 565                 acpi_evaluate_object(handler->handle, NULL, NULL, NULL);
 566         pr_debug(PREFIX "stop query execution\n");
 567         kfree(handler);
 568 }
 569
 570 static int acpi_ec_sync_query(struct acpi_ec *ec)
 571 {
 572         u8 value = 0;
 573         int status;
 574         struct acpi_ec_query_handler *handler, *copy;
 575         if ((status = acpi_ec_query_unlocked(ec, &value)))
 576                 return status;
 577         list_for_each_entry(handler, &ec->list, node) {
 578                 if (value == handler->query_bit) {
 579                         /* have custom handler for this bit */
 580                         copy = kmalloc(sizeof(*handler), GFP_KERNEL);
 581                         if (!copy)
 582                                 return -ENOMEM;
 583                         memcpy(copy, handler, sizeof(*copy));
 584                         pr_debug(PREFIX "push query execution (0x%2x) on queue\n", value);
 585                         return acpi_os_execute((copy->func) ?
 586                                 OSL_NOTIFY_HANDLER : OSL_GPE_HANDLER,
 587                                 acpi_ec_run, copy);
 588                 }
 589         }
 590         return 0;
 591 }
 592
 593 static void acpi_ec_gpe_query(void *ec_cxt)
 594 {
 595         struct acpi_ec *ec = ec_cxt;
 596         if (!ec)
 597                 return;
 598         mutex_lock(&ec->lock);
 599         acpi_ec_sync_query(ec);
 600         mutex_unlock(&ec->lock);
 601 }
 602
 603 static int ec_check_sci(struct acpi_ec *ec, u8 state)
 604 {
 605         if (state & ACPI_EC_FLAG_SCI) {
 606                 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) {
 607                         pr_debug(PREFIX "push gpe query to the queue\n");
 608                         return acpi_os_execute(OSL_NOTIFY_HANDLER,
 609                                 acpi_ec_gpe_query, ec);
 610                 }
 611         }
 612         return 0;
 613 }
 614
 615 static u32 acpi_ec_gpe_handler(acpi_handle gpe_device,
 616         u32 gpe_number, void *data)
 617 {
 618         struct acpi_ec *ec = data;
 619
 620         pr_debug(PREFIX "~~~> interrupt\n");
 621
 622         advance_transaction(ec, acpi_ec_read_status(ec));
 623         if (ec_transaction_done(ec) &&
 624             (acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF) == 0) {
 625                 wake_up(&ec->wait);
 626                 ec_check_sci(ec, acpi_ec_read_status(ec));
 627         }
 628         return ACPI_INTERRUPT_HANDLED | ACPI_REENABLE_GPE;
 629 }
 630
 631 /* --------------------------------------------------------------------------
 632                              Address Space Management
 633    -------------------------------------------------------------------------- */
 634
 635 static acpi_status
 636 acpi_ec_space_handler(u32 function, acpi_physical_address address,
 637                       u32 bits, u64 *value64,
 638                       void *handler_context, void *region_context)
 639 {
 640         struct acpi_ec *ec = handler_context;
 641         int result = 0, i, bytes = bits / 8;
 642         u8 *value = (u8 *)value64;
 643
 644         if ((address > 0xFF) || !value || !handler_context)
 645                 return AE_BAD_PARAMETER;
 646
 647         if (function != ACPI_READ && function != ACPI_WRITE)
 648                 return AE_BAD_PARAMETER;
 649
 650         if (EC_FLAGS_MSI || bits > 8)
 651                 acpi_ec_burst_enable(ec);
 652
 653         for (i = 0; i < bytes; ++i, ++address, ++value)
 654                 result = (function == ACPI_READ) ?
 655                         acpi_ec_read(ec, address, value) :
 656                         acpi_ec_write(ec, address, *value);
 657
 658         if (EC_FLAGS_MSI || bits > 8)
 659                 acpi_ec_burst_disable(ec);
 660
 661         switch (result) {
 662         case -EINVAL:
 663                 return AE_BAD_PARAMETER;
 664                 break;
 665         case -ENODEV:
 666                 return AE_NOT_FOUND;
 667                 break;
 668         case -ETIME:
 669                 return AE_TIME;
 670                 break;
 671         default:
 672                 return AE_OK;
 673         }
 674 }
 675
 676 /* --------------------------------------------------------------------------
 677                                Driver Interface
 678    -------------------------------------------------------------------------- */
 679 static acpi_status
 680 ec_parse_io_ports(struct acpi_resource *resource, void *context);
 681
 682 static struct acpi_ec *make_acpi_ec(void)
 683 {
 684         struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
 685         if (!ec)
 686                 return NULL;
 687         ec->flags = 1 << EC_FLAGS_QUERY_PENDING;
 688         mutex_init(&ec->lock);
 689         init_waitqueue_head(&ec->wait);
 690         INIT_LIST_HEAD(&ec->list);
 691         spin_lock_init(&ec->curr_lock);
 692         return ec;
 693 }
 694
 695 static acpi_status
 696 acpi_ec_register_query_methods(acpi_handle handle, u32 level,
 697                                void *context, void **return_value)
 698 {
 699         char node_name[5];
 700         struct acpi_buffer buffer = { sizeof(node_name), node_name };
 701         struct acpi_ec *ec = context;
 702         int value = 0;
 703         acpi_status status;
 704
 705         status = acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
 706
 707         if (ACPI_SUCCESS(status) && sscanf(node_name, "_Q%x", &value) == 1) {
 708                 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL);
 709         }
 710         return AE_OK;
 711 }
 712
 713 static acpi_status
 714 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
 715 {
 716         acpi_status status;
 717         unsigned long long tmp = 0;
 718
 719         struct acpi_ec *ec = context;
 720
 721         /* clear addr values, ec_parse_io_ports depend on it */
 722         ec->command_addr = ec->data_addr = 0;
 723
 724         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
 725                                      ec_parse_io_ports, ec);
 726         if (ACPI_FAILURE(status))
 727                 return status;
 728
 729         /* Get GPE bit assignment (EC events). */
 730         /* TODO: Add support for _GPE returning a package */
 731         status = acpi_evaluate_integer(handle, "_GPE", NULL, &tmp);
 732         if (ACPI_FAILURE(status))
 733                 return status;
 734         ec->gpe = tmp;
 735         /* Use the global lock for all EC transactions? */
 736         tmp = 0;
 737         acpi_evaluate_integer(handle, "_GLK", NULL, &tmp);
 738         ec->global_lock = tmp;
 739         ec->handle = handle;
 740         return AE_CTRL_TERMINATE;
 741 }
 742
 743 static int ec_install_handlers(struct acpi_ec *ec)
 744 {
 745         acpi_status status;
 746         if (test_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags))
 747                 return 0;
 748         status = acpi_install_gpe_handler(NULL, ec->gpe,
 749                                   ACPI_GPE_EDGE_TRIGGERED,
 750                                   &acpi_ec_gpe_handler, ec);
 751         if (ACPI_FAILURE(status))
 752                 return -ENODEV;
 753
 754         acpi_enable_gpe(NULL, ec->gpe);
 755         status = acpi_install_address_space_handler(ec->handle,
 756                                                     ACPI_ADR_SPACE_EC,
 757                                                     &acpi_ec_space_handler,
 758                                                     NULL, ec);
 759         if (ACPI_FAILURE(status)) {
 760                 if (status == AE_NOT_FOUND) {
 761                         /*
 762                          * Maybe OS fails in evaluating the _REG object.
 763                          * The AE_NOT_FOUND error will be ignored and OS
 764                          * continue to initialize EC.
 765                          */
 766                         printk(KERN_ERR "Fail in evaluating the _REG object"
 767                                 " of EC device. Broken bios is suspected.\n");
 768                 } else {
 769                         acpi_remove_gpe_handler(NULL, ec->gpe,
 770                                 &acpi_ec_gpe_handler);
 771                         acpi_disable_gpe(NULL, ec->gpe);
 772                         return -ENODEV;
 773                 }
 774         }
 775
 776         set_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
 777         return 0;
 778 }
 779
 780 static void ec_remove_handlers(struct acpi_ec *ec)
 781 {
 782         acpi_disable_gpe(NULL, ec->gpe);
 783         if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle,
 784                                 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler)))
 785                 pr_err(PREFIX "failed to remove space handler\n");
 786         if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe,
 787                                 &acpi_ec_gpe_handler)))
 788                 pr_err(PREFIX "failed to remove gpe handler\n");
 789         clear_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
 790 }
 791
 792 static int acpi_ec_add(struct acpi_device *device)
 793 {
 794         struct acpi_ec *ec = NULL;
 795         int ret;
 796
 797         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
 798         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
 799
 800         /* Check for boot EC */
 801         if (boot_ec &&
 802             (boot_ec->handle == device->handle ||
 803              boot_ec->handle == ACPI_ROOT_OBJECT)) {
 804                 ec = boot_ec;
 805                 boot_ec = NULL;
 806         } else {
 807                 ec = make_acpi_ec();
 808                 if (!ec)
 809                         return -ENOMEM;
 810         }
 811         if (ec_parse_device(device->handle, 0, ec, NULL) !=
 812                 AE_CTRL_TERMINATE) {
 813                         kfree(ec);
 814                         return -EINVAL;
 815         }
 816
 817         /* Find and register all query methods */
 818         acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1,
 819                             acpi_ec_register_query_methods, NULL, ec, NULL);
 820
 821         if (!first_ec)
 822                 first_ec = ec;
 823         device->driver_data = ec;
 824
 825         ret = !!request_region(ec->data_addr, 1, "EC data");
 826         WARN(!ret, "Could not request EC data io port 0x%lx", ec->data_addr);
 827         ret = !!request_region(ec->command_addr, 1, "EC cmd");
 828         WARN(!ret, "Could not request EC cmd io port 0x%lx", ec->command_addr);
 829
 830         pr_info(PREFIX "GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n",
 831                           ec->gpe, ec->command_addr, ec->data_addr);
 832
 833         ret = ec_install_handlers(ec);
 834
 835         /* EC is fully operational, allow queries */
 836         clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
 837         return ret;
 838 }
 839
 840 static int acpi_ec_remove(struct acpi_device *device, int type)
 841 {
 842         struct acpi_ec *ec;
 843         struct acpi_ec_query_handler *handler, *tmp;
 844
 845         if (!device)
 846                 return -EINVAL;
 847
 848         ec = acpi_driver_data(device);
 849         ec_remove_handlers(ec);
 850         mutex_lock(&ec->lock);
 851         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
 852                 list_del(&handler->node);
 853                 kfree(handler);
 854         }
 855         mutex_unlock(&ec->lock);
 856         release_region(ec->data_addr, 1);
 857         release_region(ec->command_addr, 1);
 858         device->driver_data = NULL;
 859         if (ec == first_ec)
 860                 first_ec = NULL;
 861         kfree(ec);
 862         return 0;
 863 }
 864
 865 static acpi_status
 866 ec_parse_io_ports(struct acpi_resource *resource, void *context)
 867 {
 868         struct acpi_ec *ec = context;
 869
 870         if (resource->type != ACPI_RESOURCE_TYPE_IO)
 871                 return AE_OK;
 872
 873         /*
 874          * The first address region returned is the data port, and
 875          * the second address region returned is the status/command
 876          * port.
 877          */
 878         if (ec->data_addr == 0)
 879                 ec->data_addr = resource->data.io.minimum;
 880         else if (ec->command_addr == 0)
 881                 ec->command_addr = resource->data.io.minimum;
 882         else
 883                 return AE_CTRL_TERMINATE;
 884
 885         return AE_OK;
 886 }
 887
 888 int __init acpi_boot_ec_enable(void)
 889 {
 890         if (!boot_ec || test_bit(EC_FLAGS_HANDLERS_INSTALLED, &boot_ec->flags))
 891                 return 0;
 892         if (!ec_install_handlers(boot_ec)) {
 893                 first_ec = boot_ec;
 894                 return 0;
 895         }
 896         return -EFAULT;
 897 }
 898
 899 static const struct acpi_device_id ec_device_ids[] = {
 900         {"PNP0C09", 0},
 901         {"", 0},
 902 };
 903
 904 /* Some BIOS do not survive early DSDT scan, skip it */
 905 static int ec_skip_dsdt_scan(const struct dmi_system_id *id)
 906 {
 907         EC_FLAGS_SKIP_DSDT_SCAN = 1;
 908         return 0;
 909 }
 910
 911 /* ASUStek often supplies us with broken ECDT, validate it */
 912 static int ec_validate_ecdt(const struct dmi_system_id *id)
 913 {
 914         EC_FLAGS_VALIDATE_ECDT = 1;
 915         return 0;
 916 }
 917
 918 /* MSI EC needs special treatment, enable it */
 919 static int ec_flag_msi(const struct dmi_system_id *id)
 920 {
 921         printk(KERN_DEBUG PREFIX "Detected MSI hardware, enabling workarounds.\n");
 922         EC_FLAGS_MSI = 1;
 923         EC_FLAGS_VALIDATE_ECDT = 1;
 924         return 0;
 925 }
 926
 927 static struct dmi_system_id __initdata ec_dmi_table[] = {
 928         {
 929         ec_skip_dsdt_scan, "Compal JFL92", {
 930         DMI_MATCH(DMI_BIOS_VENDOR, "COMPAL"),
 931         DMI_MATCH(DMI_BOARD_NAME, "JFL92") }, NULL},
 932         {
 933         ec_flag_msi, "MSI hardware", {
 934         DMI_MATCH(DMI_BIOS_VENDOR, "Micro-Star")}, NULL},
 935         {
 936         ec_flag_msi, "MSI hardware", {
 937         DMI_MATCH(DMI_SYS_VENDOR, "Micro-Star")}, NULL},
 938         {
 939         ec_flag_msi, "MSI hardware", {
 940         DMI_MATCH(DMI_CHASSIS_VENDOR, "MICRO-Star")}, NULL},
 941         {
 942         ec_flag_msi, "MSI hardware", {
 943         DMI_MATCH(DMI_CHASSIS_VENDOR, "MICRO-STAR")}, NULL},
 944         {
 945         ec_flag_msi, "Quanta hardware", {
 946         DMI_MATCH(DMI_SYS_VENDOR, "Quanta"),
 947         DMI_MATCH(DMI_PRODUCT_NAME, "TW8/SW8/DW8"),}, NULL},
 948         {
 949         ec_flag_msi, "Quanta hardware", {
 950         DMI_MATCH(DMI_SYS_VENDOR, "Quanta"),
 951         DMI_MATCH(DMI_PRODUCT_NAME, "TW9/SW9"),}, NULL},
 952         {
 953         ec_validate_ecdt, "ASUS hardware", {
 954         DMI_MATCH(DMI_BIOS_VENDOR, "ASUS") }, NULL},
 955         {
 956         ec_validate_ecdt, "ASUS hardware", {
 957         DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer Inc.") }, NULL},
 958         {},
 959 };
 960
 961
 962 int __init acpi_ec_ecdt_probe(void)
 963 {
 964         acpi_status status;
 965         struct acpi_ec *saved_ec = NULL;
 966         struct acpi_table_ecdt *ecdt_ptr;
 967
 968         boot_ec = make_acpi_ec();
 969         if (!boot_ec)
 970                 return -ENOMEM;
 971         /*
 972          * Generate a boot ec context
 973          */
 974         dmi_check_system(ec_dmi_table);
 975         status = acpi_get_table(ACPI_SIG_ECDT, 1,
 976                                 (struct acpi_table_header **)&ecdt_ptr);
 977         if (ACPI_SUCCESS(status)) {
 978                 pr_info(PREFIX "EC description table is found, configuring boot EC\n");
 979                 boot_ec->command_addr = ecdt_ptr->control.address;
 980                 boot_ec->data_addr = ecdt_ptr->data.address;
 981                 boot_ec->gpe = ecdt_ptr->gpe;
 982                 boot_ec->handle = ACPI_ROOT_OBJECT;
 983                 acpi_get_handle(ACPI_ROOT_OBJECT, ecdt_ptr->id, &boot_ec->handle);
 984                 /* Don't trust ECDT, which comes from ASUSTek */
 985                 if (!EC_FLAGS_VALIDATE_ECDT)
 986                         goto install;
 987                 saved_ec = kmemdup(boot_ec, sizeof(struct acpi_ec), GFP_KERNEL);
 988                 if (!saved_ec)
 989                         return -ENOMEM;
 990         /* fall through */
 991         }
 992
 993         if (EC_FLAGS_SKIP_DSDT_SCAN)
 994                 return -ENODEV;
 995
 996         /* This workaround is needed only on some broken machines,
 997          * which require early EC, but fail to provide ECDT */
 998         printk(KERN_DEBUG PREFIX "Look up EC in DSDT\n");
 999         status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device,
1000                                         boot_ec, NULL);
1001         /* Check that acpi_get_devices actually find something */
1002         if (ACPI_FAILURE(status) || !boot_ec->handle)
1003                 goto error;
1004         if (saved_ec) {
1005                 /* try to find good ECDT from ASUSTek */
1006                 if (saved_ec->command_addr != boot_ec->command_addr ||
1007                     saved_ec->data_addr != boot_ec->data_addr ||
1008                     saved_ec->gpe != boot_ec->gpe ||
1009                     saved_ec->handle != boot_ec->handle)
1010                         pr_info(PREFIX "ASUSTek keeps feeding us with broken "
1011                         "ECDT tables, which are very hard to workaround. "
1012                         "Trying to use DSDT EC info instead. Please send "
1013                         "output of acpidump to linux-acpi@vger.kernel.org\n");
1014                 kfree(saved_ec);
1015                 saved_ec = NULL;
1016         } else {
1017                 /* We really need to limit this workaround, the only ASUS,
1018                 * which needs it, has fake EC._INI method, so use it as flag.
1019                 * Keep boot_ec struct as it will be needed soon.
1020                 */
1021                 acpi_handle dummy;
1022                 if (!dmi_name_in_vendors("ASUS") ||
1023                     ACPI_FAILURE(acpi_get_handle(boot_ec->handle, "_INI",
1024                                                         &dummy)))
1025                         return -ENODEV;
1026         }
1027 install:
1028         if (!ec_install_handlers(boot_ec)) {
1029                 first_ec = boot_ec;
1030                 return 0;
1031         }
1032 error:
1033         kfree(boot_ec);
1034         boot_ec = NULL;
1035         return -ENODEV;
1036 }
1037
1038 static struct acpi_driver acpi_ec_driver = {
1039         .name = "ec",
1040         .class = ACPI_EC_CLASS,
1041         .ids = ec_device_ids,
1042         .ops = {
1043                 .add = acpi_ec_add,
1044                 .remove = acpi_ec_remove,
1045                 },
1046 };
1047
1048 int __init acpi_ec_init(void)
1049 {
1050         int result = 0;
1051
1052         /* Now register the driver for the EC */
1053         result = acpi_bus_register_driver(&acpi_ec_driver);
1054         if (result < 0)
1055                 return -ENODEV;
1056
1057         return result;
1058 }
1059
1060 /* EC driver currently not unloadable */
1061 #if 0
1062 static void __exit acpi_ec_exit(void)
1063 {
1064
1065         acpi_bus_unregister_driver(&acpi_ec_driver);
1066         return;
1067 }
1068 #endif  /* 0 */