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 <acpi/actypes.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 #undef PREFIX
  52 #define PREFIX                          "ACPI: EC: "
  53
  54 /* EC status register */
  55 #define ACPI_EC_FLAG_OBF        0x01    /* Output buffer full */
  56 #define ACPI_EC_FLAG_IBF        0x02    /* Input buffer full */
  57 #define ACPI_EC_FLAG_BURST      0x10    /* burst mode */
  58 #define ACPI_EC_FLAG_SCI        0x20    /* EC-SCI occurred */
  59
  60 /* EC commands */
  61 enum ec_command {
  62         ACPI_EC_COMMAND_READ = 0x80,
  63         ACPI_EC_COMMAND_WRITE = 0x81,
  64         ACPI_EC_BURST_ENABLE = 0x82,
  65         ACPI_EC_BURST_DISABLE = 0x83,
  66         ACPI_EC_COMMAND_QUERY = 0x84,
  67 };
  68
  69 #define ACPI_EC_DELAY           500     /* Wait 500ms max. during EC ops */
  70 #define ACPI_EC_UDELAY_GLK      1000    /* Wait 1ms max. to get global lock */
  71 #define ACPI_EC_UDELAY          100     /* Wait 100us before polling EC again */
  72
  73 #define ACPI_EC_STORM_THRESHOLD 20      /* number of false interrupts
  74                                            per one transaction */
  75
  76 enum {
  77         EC_FLAGS_QUERY_PENDING,         /* Query is pending */
  78         EC_FLAGS_GPE_MODE,              /* Expect GPE to be sent
  79                                          * for status change */
  80         EC_FLAGS_NO_GPE,                /* Don't use GPE mode */
  81         EC_FLAGS_GPE_STORM,             /* GPE storm detected */
  82         EC_FLAGS_HANDLERS_INSTALLED     /* Handlers for GPE and
  83                                          * OpReg are installed */
  84 };
  85
  86 /* If we find an EC via the ECDT, we need to keep a ptr to its context */
  87 /* External interfaces use first EC only, so remember */
  88 typedef int (*acpi_ec_query_func) (void *data);
  89
  90 struct acpi_ec_query_handler {
  91         struct list_head node;
  92         acpi_ec_query_func func;
  93         acpi_handle handle;
  94         void *data;
  95         u8 query_bit;
  96 };
  97
  98 struct transaction {
  99         const u8 *wdata;
 100         u8 *rdata;
 101         unsigned short irq_count;
 102         u8 command;
 103         u8 wi;
 104         u8 ri;
 105         u8 wlen;
 106         u8 rlen;
 107         bool done;
 108 };
 109
 110 static struct acpi_ec {
 111         acpi_handle handle;
 112         unsigned long gpe;
 113         unsigned long command_addr;
 114         unsigned long data_addr;
 115         unsigned long global_lock;
 116         unsigned long flags;
 117         struct mutex lock;
 118         wait_queue_head_t wait;
 119         struct list_head list;
 120         struct transaction *curr;
 121         spinlock_t curr_lock;
 122 } *boot_ec, *first_ec;
 123
 124 /*
 125  * Some Asus system have exchanged ECDT data/command IO addresses.
 126  */
 127 static int print_ecdt_error(const struct dmi_system_id *id)
 128 {
 129         printk(KERN_NOTICE PREFIX "%s detected - "
 130                 "ECDT has exchanged control/data I/O address\n",
 131                 id->ident);
 132         return 0;
 133 }
 134
 135 static struct dmi_system_id __cpuinitdata ec_dmi_table[] = {
 136         {
 137         print_ecdt_error, "Asus L4R", {
 138         DMI_MATCH(DMI_BIOS_VERSION, "1008.006"),
 139         DMI_MATCH(DMI_PRODUCT_NAME, "L4R"),
 140         DMI_MATCH(DMI_BOARD_NAME, "L4R") }, NULL},
 141         {
 142         print_ecdt_error, "Asus M6R", {
 143         DMI_MATCH(DMI_BIOS_VERSION, "0207"),
 144         DMI_MATCH(DMI_PRODUCT_NAME, "M6R"),
 145         DMI_MATCH(DMI_BOARD_NAME, "M6R") }, NULL},
 146         {},
 147 };
 148
 149 /* --------------------------------------------------------------------------
 150                              Transaction Management
 151    -------------------------------------------------------------------------- */
 152
 153 static inline u8 acpi_ec_read_status(struct acpi_ec *ec)
 154 {
 155         u8 x = inb(ec->command_addr);
 156         pr_debug(PREFIX "---> status = 0x%2.2x\n", x);
 157         return x;
 158 }
 159
 160 static inline u8 acpi_ec_read_data(struct acpi_ec *ec)
 161 {
 162         u8 x = inb(ec->data_addr);
 163         pr_debug(PREFIX "---> data = 0x%2.2x\n", x);
 164         return x;
 165 }
 166
 167 static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command)
 168 {
 169         pr_debug(PREFIX "<--- command = 0x%2.2x\n", command);
 170         outb(command, ec->command_addr);
 171 }
 172
 173 static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data)
 174 {
 175         pr_debug(PREFIX "<--- data = 0x%2.2x\n", data);
 176         outb(data, ec->data_addr);
 177 }
 178
 179 static int ec_transaction_done(struct acpi_ec *ec)
 180 {
 181         unsigned long flags;
 182         int ret = 0;
 183         spin_lock_irqsave(&ec->curr_lock, flags);
 184         if (!ec->curr || ec->curr->done)
 185                 ret = 1;
 186         spin_unlock_irqrestore(&ec->curr_lock, flags);
 187         return ret;
 188 }
 189
 190 static void start_transaction(struct acpi_ec *ec)
 191 {
 192         ec->curr->irq_count = ec->curr->wi = ec->curr->ri = 0;
 193         ec->curr->done = false;
 194         acpi_ec_write_cmd(ec, ec->curr->command);
 195 }
 196
 197 static void gpe_transaction(struct acpi_ec *ec, u8 status)
 198 {
 199         unsigned long flags;
 200         spin_lock_irqsave(&ec->curr_lock, flags);
 201         if (!ec->curr)
 202                 goto unlock;
 203         if (ec->curr->wlen > ec->curr->wi) {
 204                 if ((status & ACPI_EC_FLAG_IBF) == 0)
 205                         acpi_ec_write_data(ec,
 206                                 ec->curr->wdata[ec->curr->wi++]);
 207                 else
 208                         goto err;
 209         } else if (ec->curr->rlen > ec->curr->ri) {
 210                 if ((status & ACPI_EC_FLAG_OBF) == 1) {
 211                         ec->curr->rdata[ec->curr->ri++] = acpi_ec_read_data(ec);
 212                         if (ec->curr->rlen == ec->curr->ri)
 213                                 ec->curr->done = true;
 214                 } else
 215                         goto err;
 216         } else if (ec->curr->wlen == ec->curr->wi &&
 217                    (status & ACPI_EC_FLAG_IBF) == 0)
 218                 ec->curr->done = true;
 219         goto unlock;
 220 err:
 221         /* false interrupt, state didn't change */
 222         ++ec->curr->irq_count;
 223 unlock:
 224         spin_unlock_irqrestore(&ec->curr_lock, flags);
 225 }
 226
 227 static int acpi_ec_wait(struct acpi_ec *ec)
 228 {
 229         if (wait_event_timeout(ec->wait, ec_transaction_done(ec),
 230                                msecs_to_jiffies(ACPI_EC_DELAY)))
 231                 return 0;
 232         /* try restart command if we get any false interrupts */
 233         if (ec->curr->irq_count &&
 234             (acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF) == 0) {
 235                 pr_debug(PREFIX "controller reset, restart transaction\n");
 236                 start_transaction(ec);
 237                 if (wait_event_timeout(ec->wait, ec_transaction_done(ec),
 238                                         msecs_to_jiffies(ACPI_EC_DELAY)))
 239                         return 0;
 240         }
 241         /* missing GPEs, switch back to poll mode */
 242         if (printk_ratelimit())
 243                 pr_info(PREFIX "missing confirmations, "
 244                                 "switch off interrupt mode.\n");
 245         set_bit(EC_FLAGS_NO_GPE, &ec->flags);
 246         clear_bit(EC_FLAGS_GPE_MODE, &ec->flags);
 247         return 1;
 248 }
 249
 250 static void acpi_ec_gpe_query(void *ec_cxt);
 251
 252 static int ec_check_sci(struct acpi_ec *ec, u8 state)
 253 {
 254         if (state & ACPI_EC_FLAG_SCI) {
 255                 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags))
 256                         return acpi_os_execute(OSL_EC_BURST_HANDLER,
 257                                 acpi_ec_gpe_query, ec);
 258         }
 259         return 0;
 260 }
 261
 262 static int ec_poll(struct acpi_ec *ec)
 263 {
 264         unsigned long delay = jiffies + msecs_to_jiffies(ACPI_EC_DELAY);
 265         udelay(ACPI_EC_UDELAY);
 266         while (time_before(jiffies, delay)) {
 267                 gpe_transaction(ec, acpi_ec_read_status(ec));
 268                 udelay(ACPI_EC_UDELAY);
 269                 if (ec_transaction_done(ec))
 270                         return 0;
 271         }
 272         return -ETIME;
 273 }
 274
 275 static int acpi_ec_transaction_unlocked(struct acpi_ec *ec,
 276                                         struct transaction *t,
 277                                         int force_poll)
 278 {
 279         unsigned long tmp;
 280         int ret = 0;
 281         pr_debug(PREFIX "transaction start\n");
 282         /* disable GPE during transaction if storm is detected */
 283         if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
 284                 clear_bit(EC_FLAGS_GPE_MODE, &ec->flags);
 285                 acpi_disable_gpe(NULL, ec->gpe);
 286         }
 287         /* start transaction */
 288         spin_lock_irqsave(&ec->curr_lock, tmp);
 289         /* following two actions should be kept atomic */
 290         ec->curr = t;
 291         start_transaction(ec);
 292         if (ec->curr->command == ACPI_EC_COMMAND_QUERY)
 293                 clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
 294         spin_unlock_irqrestore(&ec->curr_lock, tmp);
 295         /* if we selected poll mode or failed in GPE-mode do a poll loop */
 296         if (force_poll ||
 297             !test_bit(EC_FLAGS_GPE_MODE, &ec->flags) ||
 298             acpi_ec_wait(ec))
 299                 ret = ec_poll(ec);
 300         pr_debug(PREFIX "transaction end\n");
 301         spin_lock_irqsave(&ec->curr_lock, tmp);
 302         ec->curr = NULL;
 303         spin_unlock_irqrestore(&ec->curr_lock, tmp);
 304         if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
 305                 /* check if we received SCI during transaction */
 306                 ec_check_sci(ec, acpi_ec_read_status(ec));
 307                 /* it is safe to enable GPE outside of transaction */
 308                 acpi_enable_gpe(NULL, ec->gpe);
 309         } else if (test_bit(EC_FLAGS_GPE_MODE, &ec->flags) &&
 310                    t->irq_count > ACPI_EC_STORM_THRESHOLD) {
 311                 pr_info(PREFIX "GPE storm detected, "
 312                         "transactions will use polling mode\n");
 313                 set_bit(EC_FLAGS_GPE_STORM, &ec->flags);
 314         }
 315         return ret;
 316 }
 317
 318 static int ec_check_ibf0(struct acpi_ec *ec)
 319 {
 320         u8 status = acpi_ec_read_status(ec);
 321         return (status & ACPI_EC_FLAG_IBF) == 0;
 322 }
 323
 324 static int ec_wait_ibf0(struct acpi_ec *ec)
 325 {
 326         unsigned long delay = jiffies + msecs_to_jiffies(ACPI_EC_DELAY);
 327         /* interrupt wait manually if GPE mode is not active */
 328         unsigned long timeout = test_bit(EC_FLAGS_GPE_MODE, &ec->flags) ?
 329                 msecs_to_jiffies(ACPI_EC_DELAY) : msecs_to_jiffies(1);
 330         while (time_before(jiffies, delay))
 331                 if (wait_event_timeout(ec->wait, ec_check_ibf0(ec), timeout))
 332                         return 0;
 333         return -ETIME;
 334 }
 335
 336 static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t,
 337                                int force_poll)
 338 {
 339         int status;
 340         u32 glk;
 341         if (!ec || (!t) || (t->wlen && !t->wdata) || (t->rlen && !t->rdata))
 342                 return -EINVAL;
 343         if (t->rdata)
 344                 memset(t->rdata, 0, t->rlen);
 345         mutex_lock(&ec->lock);
 346         if (ec->global_lock) {
 347                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 348                 if (ACPI_FAILURE(status)) {
 349                         status = -ENODEV;
 350                         goto unlock;
 351                 }
 352         }
 353         if (ec_wait_ibf0(ec)) {
 354                 pr_err(PREFIX "input buffer is not empty, "
 355                                 "aborting transaction\n");
 356                 status = -ETIME;
 357                 goto end;
 358         }
 359         status = acpi_ec_transaction_unlocked(ec, t, force_poll);
 360 end:
 361         if (ec->global_lock)
 362                 acpi_release_global_lock(glk);
 363 unlock:
 364         mutex_unlock(&ec->lock);
 365         return status;
 366 }
 367
 368 /*
 369  * Note: samsung nv5000 doesn't work with ec burst mode.
 370  * http://bugzilla.kernel.org/show_bug.cgi?id=4980
 371  */
 372 int acpi_ec_burst_enable(struct acpi_ec *ec)
 373 {
 374         u8 d;
 375         struct transaction t = {.command = ACPI_EC_BURST_ENABLE,
 376                                 .wdata = NULL, .rdata = &d,
 377                                 .wlen = 0, .rlen = 1};
 378
 379         return acpi_ec_transaction(ec, &t, 0);
 380 }
 381
 382 int acpi_ec_burst_disable(struct acpi_ec *ec)
 383 {
 384         struct transaction t = {.command = ACPI_EC_BURST_DISABLE,
 385                                 .wdata = NULL, .rdata = NULL,
 386                                 .wlen = 0, .rlen = 0};
 387
 388         return (acpi_ec_read_status(ec) & ACPI_EC_FLAG_BURST) ?
 389                                 acpi_ec_transaction(ec, &t, 0) : 0;
 390 }
 391
 392 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 * data)
 393 {
 394         int result;
 395         u8 d;
 396         struct transaction t = {.command = ACPI_EC_COMMAND_READ,
 397                                 .wdata = &address, .rdata = &d,
 398                                 .wlen = 1, .rlen = 1};
 399
 400         result = acpi_ec_transaction(ec, &t, 0);
 401         *data = d;
 402         return result;
 403 }
 404
 405 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
 406 {
 407         u8 wdata[2] = { address, data };
 408         struct transaction t = {.command = ACPI_EC_COMMAND_WRITE,
 409                                 .wdata = wdata, .rdata = NULL,
 410                                 .wlen = 2, .rlen = 0};
 411
 412         return acpi_ec_transaction(ec, &t, 0);
 413 }
 414
 415 /*
 416  * Externally callable EC access functions. For now, assume 1 EC only
 417  */
 418 int ec_burst_enable(void)
 419 {
 420         if (!first_ec)
 421                 return -ENODEV;
 422         return acpi_ec_burst_enable(first_ec);
 423 }
 424
 425 EXPORT_SYMBOL(ec_burst_enable);
 426
 427 int ec_burst_disable(void)
 428 {
 429         if (!first_ec)
 430                 return -ENODEV;
 431         return acpi_ec_burst_disable(first_ec);
 432 }
 433
 434 EXPORT_SYMBOL(ec_burst_disable);
 435
 436 int ec_read(u8 addr, u8 * val)
 437 {
 438         int err;
 439         u8 temp_data;
 440
 441         if (!first_ec)
 442                 return -ENODEV;
 443
 444         err = acpi_ec_read(first_ec, addr, &temp_data);
 445
 446         if (!err) {
 447                 *val = temp_data;
 448                 return 0;
 449         } else
 450                 return err;
 451 }
 452
 453 EXPORT_SYMBOL(ec_read);
 454
 455 int ec_write(u8 addr, u8 val)
 456 {
 457         int err;
 458
 459         if (!first_ec)
 460                 return -ENODEV;
 461
 462         err = acpi_ec_write(first_ec, addr, val);
 463
 464         return err;
 465 }
 466
 467 EXPORT_SYMBOL(ec_write);
 468
 469 int ec_transaction(u8 command,
 470                    const u8 * wdata, unsigned wdata_len,
 471                    u8 * rdata, unsigned rdata_len,
 472                    int force_poll)
 473 {
 474         struct transaction t = {.command = command,
 475                                 .wdata = wdata, .rdata = rdata,
 476                                 .wlen = wdata_len, .rlen = rdata_len};
 477         if (!first_ec)
 478                 return -ENODEV;
 479
 480         return acpi_ec_transaction(first_ec, &t, force_poll);
 481 }
 482
 483 EXPORT_SYMBOL(ec_transaction);
 484
 485 static int acpi_ec_query(struct acpi_ec *ec, u8 * data)
 486 {
 487         int result;
 488         u8 d;
 489         struct transaction t = {.command = ACPI_EC_COMMAND_QUERY,
 490                                 .wdata = NULL, .rdata = &d,
 491                                 .wlen = 0, .rlen = 1};
 492         if (!ec || !data)
 493                 return -EINVAL;
 494
 495         /*
 496          * Query the EC to find out which _Qxx method we need to evaluate.
 497          * Note that successful completion of the query causes the ACPI_EC_SCI
 498          * bit to be cleared (and thus clearing the interrupt source).
 499          */
 500
 501         result = acpi_ec_transaction(ec, &t, 0);
 502         if (result)
 503                 return result;
 504
 505         if (!d)
 506                 return -ENODATA;
 507
 508         *data = d;
 509         return 0;
 510 }
 511
 512 /* --------------------------------------------------------------------------
 513                                 Event Management
 514    -------------------------------------------------------------------------- */
 515 int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
 516                               acpi_handle handle, acpi_ec_query_func func,
 517                               void *data)
 518 {
 519         struct acpi_ec_query_handler *handler =
 520             kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL);
 521         if (!handler)
 522                 return -ENOMEM;
 523
 524         handler->query_bit = query_bit;
 525         handler->handle = handle;
 526         handler->func = func;
 527         handler->data = data;
 528         mutex_lock(&ec->lock);
 529         list_add(&handler->node, &ec->list);
 530         mutex_unlock(&ec->lock);
 531         return 0;
 532 }
 533
 534 EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler);
 535
 536 void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit)
 537 {
 538         struct acpi_ec_query_handler *handler, *tmp;
 539         mutex_lock(&ec->lock);
 540         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
 541                 if (query_bit == handler->query_bit) {
 542                         list_del(&handler->node);
 543                         kfree(handler);
 544                 }
 545         }
 546         mutex_unlock(&ec->lock);
 547 }
 548
 549 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler);
 550
 551 static void acpi_ec_gpe_query(void *ec_cxt)
 552 {
 553         struct acpi_ec *ec = ec_cxt;
 554         u8 value = 0;
 555         struct acpi_ec_query_handler *handler, copy;
 556
 557         if (!ec || acpi_ec_query(ec, &value))
 558                 return;
 559         mutex_lock(&ec->lock);
 560         list_for_each_entry(handler, &ec->list, node) {
 561                 if (value == handler->query_bit) {
 562                         /* have custom handler for this bit */
 563                         memcpy(&copy, handler, sizeof(copy));
 564                         mutex_unlock(&ec->lock);
 565                         if (copy.func) {
 566                                 copy.func(copy.data);
 567                         } else if (copy.handle) {
 568                                 acpi_evaluate_object(copy.handle, NULL, NULL, NULL);
 569                         }
 570                         return;
 571                 }
 572         }
 573         mutex_unlock(&ec->lock);
 574 }
 575
 576 static u32 acpi_ec_gpe_handler(void *data)
 577 {
 578         struct acpi_ec *ec = data;
 579         u8 status;
 580
 581         pr_debug(PREFIX "~~~> interrupt\n");
 582         status = acpi_ec_read_status(ec);
 583
 584         gpe_transaction(ec, status);
 585         if (ec_transaction_done(ec) && (status & ACPI_EC_FLAG_IBF) == 0)
 586                 wake_up(&ec->wait);
 587
 588         ec_check_sci(ec, status);
 589         if (!test_bit(EC_FLAGS_GPE_MODE, &ec->flags) &&
 590             !test_bit(EC_FLAGS_NO_GPE, &ec->flags)) {
 591                 /* this is non-query, must be confirmation */
 592                 if (!test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
 593                         if (printk_ratelimit())
 594                                 pr_info(PREFIX "non-query interrupt received,"
 595                                         " switching to interrupt mode\n");
 596                 } else {
 597                         /* hush, STORM switches the mode every transaction */
 598                         pr_debug(PREFIX "non-query interrupt received,"
 599                                 " switching to interrupt mode\n");
 600                 }
 601                 set_bit(EC_FLAGS_GPE_MODE, &ec->flags);
 602         }
 603         return ACPI_INTERRUPT_HANDLED;
 604 }
 605
 606 /* --------------------------------------------------------------------------
 607                              Address Space Management
 608    -------------------------------------------------------------------------- */
 609
 610 static acpi_status
 611 acpi_ec_space_handler(u32 function, acpi_physical_address address,
 612                       u32 bits, acpi_integer *value,
 613                       void *handler_context, void *region_context)
 614 {
 615         struct acpi_ec *ec = handler_context;
 616         int result = 0, i;
 617         u8 temp = 0;
 618
 619         if ((address > 0xFF) || !value || !handler_context)
 620                 return AE_BAD_PARAMETER;
 621
 622         if (function != ACPI_READ && function != ACPI_WRITE)
 623                 return AE_BAD_PARAMETER;
 624
 625         if (bits != 8 && acpi_strict)
 626                 return AE_BAD_PARAMETER;
 627
 628         acpi_ec_burst_enable(ec);
 629
 630         if (function == ACPI_READ) {
 631                 result = acpi_ec_read(ec, address, &temp);
 632                 *value = temp;
 633         } else {
 634                 temp = 0xff & (*value);
 635                 result = acpi_ec_write(ec, address, temp);
 636         }
 637
 638         for (i = 8; unlikely(bits - i > 0); i += 8) {
 639                 ++address;
 640                 if (function == ACPI_READ) {
 641                         result = acpi_ec_read(ec, address, &temp);
 642                         (*value) |= ((acpi_integer)temp) << i;
 643                 } else {
 644                         temp = 0xff & ((*value) >> i);
 645                         result = acpi_ec_write(ec, address, temp);
 646                 }
 647         }
 648
 649         acpi_ec_burst_disable(ec);
 650
 651         switch (result) {
 652         case -EINVAL:
 653                 return AE_BAD_PARAMETER;
 654                 break;
 655         case -ENODEV:
 656                 return AE_NOT_FOUND;
 657                 break;
 658         case -ETIME:
 659                 return AE_TIME;
 660                 break;
 661         default:
 662                 return AE_OK;
 663         }
 664 }
 665
 666 /* --------------------------------------------------------------------------
 667                               FS Interface (/proc)
 668    -------------------------------------------------------------------------- */
 669
 670 static struct proc_dir_entry *acpi_ec_dir;
 671
 672 static int acpi_ec_read_info(struct seq_file *seq, void *offset)
 673 {
 674         struct acpi_ec *ec = seq->private;
 675
 676         if (!ec)
 677                 goto end;
 678
 679         seq_printf(seq, "gpe:\t\t\t0x%02x\n", (u32) ec->gpe);
 680         seq_printf(seq, "ports:\t\t\t0x%02x, 0x%02x\n",
 681                    (unsigned)ec->command_addr, (unsigned)ec->data_addr);
 682         seq_printf(seq, "use global lock:\t%s\n",
 683                    ec->global_lock ? "yes" : "no");
 684       end:
 685         return 0;
 686 }
 687
 688 static int acpi_ec_info_open_fs(struct inode *inode, struct file *file)
 689 {
 690         return single_open(file, acpi_ec_read_info, PDE(inode)->data);
 691 }
 692
 693 static struct file_operations acpi_ec_info_ops = {
 694         .open = acpi_ec_info_open_fs,
 695         .read = seq_read,
 696         .llseek = seq_lseek,
 697         .release = single_release,
 698         .owner = THIS_MODULE,
 699 };
 700
 701 static int acpi_ec_add_fs(struct acpi_device *device)
 702 {
 703         struct proc_dir_entry *entry = NULL;
 704
 705         if (!acpi_device_dir(device)) {
 706                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
 707                                                      acpi_ec_dir);
 708                 if (!acpi_device_dir(device))
 709                         return -ENODEV;
 710         }
 711
 712         entry = proc_create_data(ACPI_EC_FILE_INFO, S_IRUGO,
 713                                  acpi_device_dir(device),
 714                                  &acpi_ec_info_ops, acpi_driver_data(device));
 715         if (!entry)
 716                 return -ENODEV;
 717         return 0;
 718 }
 719
 720 static int acpi_ec_remove_fs(struct acpi_device *device)
 721 {
 722
 723         if (acpi_device_dir(device)) {
 724                 remove_proc_entry(ACPI_EC_FILE_INFO, acpi_device_dir(device));
 725                 remove_proc_entry(acpi_device_bid(device), acpi_ec_dir);
 726                 acpi_device_dir(device) = NULL;
 727         }
 728
 729         return 0;
 730 }
 731
 732 /* --------------------------------------------------------------------------
 733                                Driver Interface
 734    -------------------------------------------------------------------------- */
 735 static acpi_status
 736 ec_parse_io_ports(struct acpi_resource *resource, void *context);
 737
 738 static struct acpi_ec *make_acpi_ec(void)
 739 {
 740         struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
 741         if (!ec)
 742                 return NULL;
 743         ec->flags = 1 << EC_FLAGS_QUERY_PENDING;
 744         mutex_init(&ec->lock);
 745         init_waitqueue_head(&ec->wait);
 746         INIT_LIST_HEAD(&ec->list);
 747         spin_lock_init(&ec->curr_lock);
 748         return ec;
 749 }
 750
 751 static acpi_status
 752 acpi_ec_register_query_methods(acpi_handle handle, u32 level,
 753                                void *context, void **return_value)
 754 {
 755         struct acpi_namespace_node *node = handle;
 756         struct acpi_ec *ec = context;
 757         int value = 0;
 758         if (sscanf(node->name.ascii, "_Q%x", &value) == 1) {
 759                 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL);
 760         }
 761         return AE_OK;
 762 }
 763
 764 static acpi_status
 765 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
 766 {
 767         acpi_status status;
 768         unsigned long long tmp;
 769
 770         struct acpi_ec *ec = context;
 771         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
 772                                      ec_parse_io_ports, ec);
 773         if (ACPI_FAILURE(status))
 774                 return status;
 775
 776         /* Get GPE bit assignment (EC events). */
 777         /* TODO: Add support for _GPE returning a package */
 778         status = acpi_evaluate_integer(handle, "_GPE", NULL, &tmp);
 779         if (ACPI_FAILURE(status))
 780                 return status;
 781         ec->gpe = tmp;
 782         /* Use the global lock for all EC transactions? */
 783         acpi_evaluate_integer(handle, "_GLK", NULL, &tmp);
 784         ec->global_lock = tmp;
 785         ec->handle = handle;
 786         return AE_CTRL_TERMINATE;
 787 }
 788
 789 static void ec_remove_handlers(struct acpi_ec *ec)
 790 {
 791         if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle,
 792                                 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler)))
 793                 pr_err(PREFIX "failed to remove space handler\n");
 794         if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe,
 795                                 &acpi_ec_gpe_handler)))
 796                 pr_err(PREFIX "failed to remove gpe handler\n");
 797         clear_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
 798 }
 799
 800 static int acpi_ec_add(struct acpi_device *device)
 801 {
 802         struct acpi_ec *ec = NULL;
 803
 804         if (!device)
 805                 return -EINVAL;
 806         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
 807         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
 808
 809         /* Check for boot EC */
 810         if (boot_ec &&
 811             (boot_ec->handle == device->handle ||
 812              boot_ec->handle == ACPI_ROOT_OBJECT)) {
 813                 ec = boot_ec;
 814                 boot_ec = NULL;
 815         } else {
 816                 ec = make_acpi_ec();
 817                 if (!ec)
 818                         return -ENOMEM;
 819                 if (ec_parse_device(device->handle, 0, ec, NULL) !=
 820                     AE_CTRL_TERMINATE) {
 821                         kfree(ec);
 822                         return -EINVAL;
 823                 }
 824         }
 825
 826         ec->handle = device->handle;
 827
 828         /* Find and register all query methods */
 829         acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1,
 830                             acpi_ec_register_query_methods, ec, NULL);
 831
 832         if (!first_ec)
 833                 first_ec = ec;
 834         device->driver_data = ec;
 835         acpi_ec_add_fs(device);
 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         pr_info(PREFIX "driver started in %s mode\n",
 839                 (test_bit(EC_FLAGS_GPE_MODE, &ec->flags))?"interrupt":"poll");
 840         return 0;
 841 }
 842
 843 static int acpi_ec_remove(struct acpi_device *device, int type)
 844 {
 845         struct acpi_ec *ec;
 846         struct acpi_ec_query_handler *handler, *tmp;
 847
 848         if (!device)
 849                 return -EINVAL;
 850
 851         ec = acpi_driver_data(device);
 852         mutex_lock(&ec->lock);
 853         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
 854                 list_del(&handler->node);
 855                 kfree(handler);
 856         }
 857         mutex_unlock(&ec->lock);
 858         acpi_ec_remove_fs(device);
 859         device->driver_data = NULL;
 860         if (ec == first_ec)
 861                 first_ec = NULL;
 862         kfree(ec);
 863         return 0;
 864 }
 865
 866 static acpi_status
 867 ec_parse_io_ports(struct acpi_resource *resource, void *context)
 868 {
 869         struct acpi_ec *ec = context;
 870
 871         if (resource->type != ACPI_RESOURCE_TYPE_IO)
 872                 return AE_OK;
 873
 874         /*
 875          * The first address region returned is the data port, and
 876          * the second address region returned is the status/command
 877          * port.
 878          */
 879         if (ec->data_addr == 0)
 880                 ec->data_addr = resource->data.io.minimum;
 881         else if (ec->command_addr == 0)
 882                 ec->command_addr = resource->data.io.minimum;
 883         else
 884                 return AE_CTRL_TERMINATE;
 885
 886         return AE_OK;
 887 }
 888
 889 static int ec_install_handlers(struct acpi_ec *ec)
 890 {
 891         acpi_status status;
 892         if (test_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags))
 893                 return 0;
 894         status = acpi_install_gpe_handler(NULL, ec->gpe,
 895                                   ACPI_GPE_EDGE_TRIGGERED,
 896                                   &acpi_ec_gpe_handler, ec);
 897         if (ACPI_FAILURE(status))
 898                 return -ENODEV;
 899         acpi_set_gpe_type(NULL, ec->gpe, ACPI_GPE_TYPE_RUNTIME);
 900         acpi_enable_gpe(NULL, ec->gpe);
 901         status = acpi_install_address_space_handler(ec->handle,
 902                                                     ACPI_ADR_SPACE_EC,
 903                                                     &acpi_ec_space_handler,
 904                                                     NULL, ec);
 905         if (ACPI_FAILURE(status)) {
 906                 if (status == AE_NOT_FOUND) {
 907                         /*
 908                          * Maybe OS fails in evaluating the _REG object.
 909                          * The AE_NOT_FOUND error will be ignored and OS
 910                          * continue to initialize EC.
 911                          */
 912                         printk(KERN_ERR "Fail in evaluating the _REG object"
 913                                 " of EC device. Broken bios is suspected.\n");
 914                 } else {
 915                         acpi_remove_gpe_handler(NULL, ec->gpe,
 916                                 &acpi_ec_gpe_handler);
 917                         return -ENODEV;
 918                 }
 919         }
 920
 921         set_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
 922         return 0;
 923 }
 924
 925 static int acpi_ec_start(struct acpi_device *device)
 926 {
 927         struct acpi_ec *ec;
 928         int ret = 0;
 929
 930         if (!device)
 931                 return -EINVAL;
 932
 933         ec = acpi_driver_data(device);
 934
 935         if (!ec)
 936                 return -EINVAL;
 937
 938         ret = ec_install_handlers(ec);
 939
 940         /* EC is fully operational, allow queries */
 941         clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
 942         return ret;
 943 }
 944
 945 static int acpi_ec_stop(struct acpi_device *device, int type)
 946 {
 947         struct acpi_ec *ec;
 948         if (!device)
 949                 return -EINVAL;
 950         ec = acpi_driver_data(device);
 951         if (!ec)
 952                 return -EINVAL;
 953         ec_remove_handlers(ec);
 954
 955         return 0;
 956 }
 957
 958 int __init acpi_boot_ec_enable(void)
 959 {
 960         if (!boot_ec || test_bit(EC_FLAGS_HANDLERS_INSTALLED, &boot_ec->flags))
 961                 return 0;
 962         if (!ec_install_handlers(boot_ec)) {
 963                 first_ec = boot_ec;
 964                 return 0;
 965         }
 966         return -EFAULT;
 967 }
 968
 969 static const struct acpi_device_id ec_device_ids[] = {
 970         {"PNP0C09", 0},
 971         {"", 0},
 972 };
 973
 974 int __init acpi_ec_ecdt_probe(void)
 975 {
 976         int ret;
 977         acpi_status status;
 978         struct acpi_table_ecdt *ecdt_ptr;
 979
 980         boot_ec = make_acpi_ec();
 981         if (!boot_ec)
 982                 return -ENOMEM;
 983         /*
 984          * Generate a boot ec context
 985          */
 986         status = acpi_get_table(ACPI_SIG_ECDT, 1,
 987                                 (struct acpi_table_header **)&ecdt_ptr);
 988         if (ACPI_SUCCESS(status)) {
 989                 pr_info(PREFIX "EC description table is found, configuring boot EC\n");
 990                 boot_ec->command_addr = ecdt_ptr->control.address;
 991                 boot_ec->data_addr = ecdt_ptr->data.address;
 992                 if (dmi_check_system(ec_dmi_table)) {
 993                         /*
 994                          * If the board falls into ec_dmi_table, it means
 995                          * that ECDT table gives the incorrect command/status
 996                          * & data I/O address. Just fix it.
 997                          */
 998                         boot_ec->data_addr = ecdt_ptr->control.address;
 999                         boot_ec->command_addr = ecdt_ptr->data.address;
1000                 }
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         } else {
1005                 /* This workaround is needed only on some broken machines,
1006                  * which require early EC, but fail to provide ECDT */
1007                 acpi_handle x;
1008                 printk(KERN_DEBUG PREFIX "Look up EC in DSDT\n");
1009                 status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device,
1010                                                 boot_ec, NULL);
1011                 /* Check that acpi_get_devices actually find something */
1012                 if (ACPI_FAILURE(status) || !boot_ec->handle)
1013                         goto error;
1014                 /* We really need to limit this workaround, the only ASUS,
1015                  * which needs it, has fake EC._INI method, so use it as flag.
1016                  * Keep boot_ec struct as it will be needed soon.
1017                  */
1018                 if (ACPI_FAILURE(acpi_get_handle(boot_ec->handle, "_INI", &x)))
1019                         return -ENODEV;
1020         }
1021
1022         ret = ec_install_handlers(boot_ec);
1023         if (!ret) {
1024                 first_ec = boot_ec;
1025                 return 0;
1026         }
1027       error:
1028         kfree(boot_ec);
1029         boot_ec = NULL;
1030         return -ENODEV;
1031 }
1032
1033 static int acpi_ec_suspend(struct acpi_device *device, pm_message_t state)
1034 {
1035         struct acpi_ec *ec = acpi_driver_data(device);
1036         /* Stop using GPE */
1037         set_bit(EC_FLAGS_NO_GPE, &ec->flags);
1038         clear_bit(EC_FLAGS_GPE_MODE, &ec->flags);
1039         acpi_disable_gpe(NULL, ec->gpe);
1040         return 0;
1041 }
1042
1043 static int acpi_ec_resume(struct acpi_device *device)
1044 {
1045         struct acpi_ec *ec = acpi_driver_data(device);
1046         /* Enable use of GPE back */
1047         clear_bit(EC_FLAGS_NO_GPE, &ec->flags);
1048         acpi_enable_gpe(NULL, ec->gpe);
1049         return 0;
1050 }
1051
1052 static struct acpi_driver acpi_ec_driver = {
1053         .name = "ec",
1054         .class = ACPI_EC_CLASS,
1055         .ids = ec_device_ids,
1056         .ops = {
1057                 .add = acpi_ec_add,
1058                 .remove = acpi_ec_remove,
1059                 .start = acpi_ec_start,
1060                 .stop = acpi_ec_stop,
1061                 .suspend = acpi_ec_suspend,
1062                 .resume = acpi_ec_resume,
1063                 },
1064 };
1065
1066 static int __init acpi_ec_init(void)
1067 {
1068         int result = 0;
1069
1070         if (acpi_disabled)
1071                 return 0;
1072
1073         acpi_ec_dir = proc_mkdir(ACPI_EC_CLASS, acpi_root_dir);
1074         if (!acpi_ec_dir)
1075                 return -ENODEV;
1076
1077         /* Now register the driver for the EC */
1078         result = acpi_bus_register_driver(&acpi_ec_driver);
1079         if (result < 0) {
1080                 remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1081                 return -ENODEV;
1082         }
1083
1084         return result;
1085 }
1086
1087 subsys_initcall(acpi_ec_init);
1088
1089 /* EC driver currently not unloadable */
1090 #if 0
1091 static void __exit acpi_ec_exit(void)
1092 {
1093
1094         acpi_bus_unregister_driver(&acpi_ec_driver);
1095
1096         remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1097
1098         return;
1099 }
1100 #endif  /* 0 */