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 wlen;
 104         u8 rlen;
 105 };
 106
 107 static struct acpi_ec {
 108         acpi_handle handle;
 109         unsigned long gpe;
 110         unsigned long command_addr;
 111         unsigned long data_addr;
 112         unsigned long global_lock;
 113         unsigned long flags;
 114         struct mutex lock;
 115         wait_queue_head_t wait;
 116         struct list_head list;
 117         struct transaction *curr;
 118         spinlock_t curr_lock;
 119 } *boot_ec, *first_ec;
 120
 121 /*
 122  * Some Asus system have exchanged ECDT data/command IO addresses.
 123  */
 124 static int print_ecdt_error(const struct dmi_system_id *id)
 125 {
 126         printk(KERN_NOTICE PREFIX "%s detected - "
 127                 "ECDT has exchanged control/data I/O address\n",
 128                 id->ident);
 129         return 0;
 130 }
 131
 132 static struct dmi_system_id __cpuinitdata ec_dmi_table[] = {
 133         {
 134         print_ecdt_error, "Asus L4R", {
 135         DMI_MATCH(DMI_BIOS_VERSION, "1008.006"),
 136         DMI_MATCH(DMI_PRODUCT_NAME, "L4R"),
 137         DMI_MATCH(DMI_BOARD_NAME, "L4R") }, NULL},
 138         {
 139         print_ecdt_error, "Asus M6R", {
 140         DMI_MATCH(DMI_BIOS_VERSION, "0207"),
 141         DMI_MATCH(DMI_PRODUCT_NAME, "M6R"),
 142         DMI_MATCH(DMI_BOARD_NAME, "M6R") }, NULL},
 143         {},
 144 };
 145
 146 /* --------------------------------------------------------------------------
 147                              Transaction Management
 148    -------------------------------------------------------------------------- */
 149
 150 static inline u8 acpi_ec_read_status(struct acpi_ec *ec)
 151 {
 152         u8 x = inb(ec->command_addr);
 153         pr_debug(PREFIX "---> status = 0x%2.2x\n", x);
 154         return x;
 155 }
 156
 157 static inline u8 acpi_ec_read_data(struct acpi_ec *ec)
 158 {
 159         u8 x = inb(ec->data_addr);
 160         pr_debug(PREFIX "---> data = 0x%2.2x\n", x);
 161         return x;
 162 }
 163
 164 static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command)
 165 {
 166         pr_debug(PREFIX "<--- command = 0x%2.2x\n", command);
 167         outb(command, ec->command_addr);
 168 }
 169
 170 static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data)
 171 {
 172         pr_debug(PREFIX "<--- data = 0x%2.2x\n", data);
 173         outb(data, ec->data_addr);
 174 }
 175
 176 static int ec_transaction_done(struct acpi_ec *ec)
 177 {
 178         unsigned long flags;
 179         int ret = 0;
 180         spin_lock_irqsave(&ec->curr_lock, flags);
 181         if (!ec->curr || (!ec->curr->wlen && !ec->curr->rlen))
 182                 ret = 1;
 183         spin_unlock_irqrestore(&ec->curr_lock, flags);
 184         return ret;
 185 }
 186
 187 static void gpe_transaction(struct acpi_ec *ec, u8 status)
 188 {
 189         unsigned long flags;
 190         spin_lock_irqsave(&ec->curr_lock, flags);
 191         if (!ec->curr)
 192                 goto unlock;
 193         if (ec->curr->wlen > 0) {
 194                 if ((status & ACPI_EC_FLAG_IBF) == 0) {
 195                         acpi_ec_write_data(ec, *(ec->curr->wdata++));
 196                         --ec->curr->wlen;
 197                 } else
 198                         /* false interrupt, state didn't change */
 199                         ++ec->curr->irq_count;
 200
 201         } else if (ec->curr->rlen > 0) {
 202                 if ((status & ACPI_EC_FLAG_OBF) == 1) {
 203                         *(ec->curr->rdata++) = acpi_ec_read_data(ec);
 204                         --ec->curr->rlen;
 205                 } else
 206                         /* false interrupt, state didn't change */
 207                         ++ec->curr->irq_count;
 208         }
 209 unlock:
 210         spin_unlock_irqrestore(&ec->curr_lock, flags);
 211 }
 212
 213 static int acpi_ec_wait(struct acpi_ec *ec)
 214 {
 215         if (wait_event_timeout(ec->wait, ec_transaction_done(ec),
 216                                msecs_to_jiffies(ACPI_EC_DELAY)))
 217                 return 0;
 218         /* missing GPEs, switch back to poll mode */
 219         if (printk_ratelimit())
 220                 pr_info(PREFIX "missing confirmations, "
 221                                 "switch off interrupt mode.\n");
 222         set_bit(EC_FLAGS_NO_GPE, &ec->flags);
 223         clear_bit(EC_FLAGS_GPE_MODE, &ec->flags);
 224         return 1;
 225 }
 226
 227 static void acpi_ec_gpe_query(void *ec_cxt);
 228
 229 static int ec_check_sci(struct acpi_ec *ec, u8 state)
 230 {
 231         if (state & ACPI_EC_FLAG_SCI) {
 232                 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags))
 233                         return acpi_os_execute(OSL_EC_BURST_HANDLER,
 234                                 acpi_ec_gpe_query, ec);
 235         }
 236         return 0;
 237 }
 238
 239 static int ec_poll(struct acpi_ec *ec)
 240 {
 241         unsigned long delay = jiffies + msecs_to_jiffies(ACPI_EC_DELAY);
 242         udelay(ACPI_EC_UDELAY);
 243         while (time_before(jiffies, delay)) {
 244                 gpe_transaction(ec, acpi_ec_read_status(ec));
 245                 udelay(ACPI_EC_UDELAY);
 246                 if (ec_transaction_done(ec))
 247                         return 0;
 248         }
 249         return -ETIME;
 250 }
 251
 252 static int acpi_ec_transaction_unlocked(struct acpi_ec *ec,
 253                                         struct transaction *t,
 254                                         int force_poll)
 255 {
 256         unsigned long tmp;
 257         int ret = 0;
 258         pr_debug(PREFIX "transaction start\n");
 259         /* disable GPE during transaction if storm is detected */
 260         if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
 261                 clear_bit(EC_FLAGS_GPE_MODE, &ec->flags);
 262                 acpi_disable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
 263         }
 264         /* start transaction */
 265         spin_lock_irqsave(&ec->curr_lock, tmp);
 266         /* following two actions should be kept atomic */
 267         t->irq_count = 0;
 268         ec->curr = t;
 269         acpi_ec_write_cmd(ec, ec->curr->command);
 270         if (ec->curr->command == ACPI_EC_COMMAND_QUERY)
 271                 clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
 272         spin_unlock_irqrestore(&ec->curr_lock, tmp);
 273         /* if we selected poll mode or failed in GPE-mode do a poll loop */
 274         if (force_poll ||
 275             !test_bit(EC_FLAGS_GPE_MODE, &ec->flags) ||
 276             acpi_ec_wait(ec))
 277                 ret = ec_poll(ec);
 278         pr_debug(PREFIX "transaction end\n");
 279         spin_lock_irqsave(&ec->curr_lock, tmp);
 280         ec->curr = NULL;
 281         spin_unlock_irqrestore(&ec->curr_lock, tmp);
 282         if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
 283                 /* check if we received SCI during transaction */
 284                 ec_check_sci(ec, acpi_ec_read_status(ec));
 285                 /* it is safe to enable GPE outside of transaction */
 286                 acpi_enable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
 287         } else if (test_bit(EC_FLAGS_GPE_MODE, &ec->flags) &&
 288                    t->irq_count > ACPI_EC_STORM_THRESHOLD) {
 289                 pr_info(PREFIX "GPE storm detected, "
 290                         "transactions will use polling mode\n");
 291                 set_bit(EC_FLAGS_GPE_STORM, &ec->flags);
 292         }
 293         return ret;
 294 }
 295
 296 static int ec_check_ibf0(struct acpi_ec *ec)
 297 {
 298         u8 status = acpi_ec_read_status(ec);
 299         return (status & ACPI_EC_FLAG_IBF) == 0;
 300 }
 301
 302 static int ec_wait_ibf0(struct acpi_ec *ec)
 303 {
 304         unsigned long delay = jiffies + msecs_to_jiffies(ACPI_EC_DELAY);
 305         /* interrupt wait manually if GPE mode is not active */
 306         unsigned long timeout = test_bit(EC_FLAGS_GPE_MODE, &ec->flags) ?
 307                 msecs_to_jiffies(ACPI_EC_DELAY) : msecs_to_jiffies(1);
 308         while (time_before(jiffies, delay))
 309                 if (wait_event_timeout(ec->wait, ec_check_ibf0(ec), timeout))
 310                         return 0;
 311         return -ETIME;
 312 }
 313
 314 static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t,
 315                                int force_poll)
 316 {
 317         int status;
 318         u32 glk;
 319         if (!ec || (!t) || (t->wlen && !t->wdata) || (t->rlen && !t->rdata))
 320                 return -EINVAL;
 321         if (t->rdata)
 322                 memset(t->rdata, 0, t->rlen);
 323         mutex_lock(&ec->lock);
 324         if (ec->global_lock) {
 325                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 326                 if (ACPI_FAILURE(status)) {
 327                         status = -ENODEV;
 328                         goto unlock;
 329                 }
 330         }
 331         if (ec_wait_ibf0(ec)) {
 332                 pr_err(PREFIX "input buffer is not empty, "
 333                                 "aborting transaction\n");
 334                 status = -ETIME;
 335                 goto end;
 336         }
 337         status = acpi_ec_transaction_unlocked(ec, t, force_poll);
 338 end:
 339         if (ec->global_lock)
 340                 acpi_release_global_lock(glk);
 341 unlock:
 342         mutex_unlock(&ec->lock);
 343         return status;
 344 }
 345
 346 /*
 347  * Note: samsung nv5000 doesn't work with ec burst mode.
 348  * http://bugzilla.kernel.org/show_bug.cgi?id=4980
 349  */
 350 int acpi_ec_burst_enable(struct acpi_ec *ec)
 351 {
 352         u8 d;
 353         struct transaction t = {.command = ACPI_EC_BURST_ENABLE,
 354                                 .wdata = NULL, .rdata = &d,
 355                                 .wlen = 0, .rlen = 1};
 356
 357         return acpi_ec_transaction(ec, &t, 0);
 358 }
 359
 360 int acpi_ec_burst_disable(struct acpi_ec *ec)
 361 {
 362         struct transaction t = {.command = ACPI_EC_BURST_DISABLE,
 363                                 .wdata = NULL, .rdata = NULL,
 364                                 .wlen = 0, .rlen = 0};
 365
 366         return (acpi_ec_read_status(ec) & ACPI_EC_FLAG_BURST) ?
 367                                 acpi_ec_transaction(ec, &t, 0) : 0;
 368 }
 369
 370 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 * data)
 371 {
 372         int result;
 373         u8 d;
 374         struct transaction t = {.command = ACPI_EC_COMMAND_READ,
 375                                 .wdata = &address, .rdata = &d,
 376                                 .wlen = 1, .rlen = 1};
 377
 378         result = acpi_ec_transaction(ec, &t, 0);
 379         *data = d;
 380         return result;
 381 }
 382
 383 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
 384 {
 385         u8 wdata[2] = { address, data };
 386         struct transaction t = {.command = ACPI_EC_COMMAND_WRITE,
 387                                 .wdata = wdata, .rdata = NULL,
 388                                 .wlen = 2, .rlen = 0};
 389
 390         return acpi_ec_transaction(ec, &t, 0);
 391 }
 392
 393 /*
 394  * Externally callable EC access functions. For now, assume 1 EC only
 395  */
 396 int ec_burst_enable(void)
 397 {
 398         if (!first_ec)
 399                 return -ENODEV;
 400         return acpi_ec_burst_enable(first_ec);
 401 }
 402
 403 EXPORT_SYMBOL(ec_burst_enable);
 404
 405 int ec_burst_disable(void)
 406 {
 407         if (!first_ec)
 408                 return -ENODEV;
 409         return acpi_ec_burst_disable(first_ec);
 410 }
 411
 412 EXPORT_SYMBOL(ec_burst_disable);
 413
 414 int ec_read(u8 addr, u8 * val)
 415 {
 416         int err;
 417         u8 temp_data;
 418
 419         if (!first_ec)
 420                 return -ENODEV;
 421
 422         err = acpi_ec_read(first_ec, addr, &temp_data);
 423
 424         if (!err) {
 425                 *val = temp_data;
 426                 return 0;
 427         } else
 428                 return err;
 429 }
 430
 431 EXPORT_SYMBOL(ec_read);
 432
 433 int ec_write(u8 addr, u8 val)
 434 {
 435         int err;
 436
 437         if (!first_ec)
 438                 return -ENODEV;
 439
 440         err = acpi_ec_write(first_ec, addr, val);
 441
 442         return err;
 443 }
 444
 445 EXPORT_SYMBOL(ec_write);
 446
 447 int ec_transaction(u8 command,
 448                    const u8 * wdata, unsigned wdata_len,
 449                    u8 * rdata, unsigned rdata_len,
 450                    int force_poll)
 451 {
 452         struct transaction t = {.command = command,
 453                                 .wdata = wdata, .rdata = rdata,
 454                                 .wlen = wdata_len, .rlen = rdata_len};
 455         if (!first_ec)
 456                 return -ENODEV;
 457
 458         return acpi_ec_transaction(first_ec, &t, force_poll);
 459 }
 460
 461 EXPORT_SYMBOL(ec_transaction);
 462
 463 static int acpi_ec_query(struct acpi_ec *ec, u8 * data)
 464 {
 465         int result;
 466         u8 d;
 467         struct transaction t = {.command = ACPI_EC_COMMAND_QUERY,
 468                                 .wdata = NULL, .rdata = &d,
 469                                 .wlen = 0, .rlen = 1};
 470         if (!ec || !data)
 471                 return -EINVAL;
 472
 473         /*
 474          * Query the EC to find out which _Qxx method we need to evaluate.
 475          * Note that successful completion of the query causes the ACPI_EC_SCI
 476          * bit to be cleared (and thus clearing the interrupt source).
 477          */
 478
 479         result = acpi_ec_transaction(ec, &t, 0);
 480         if (result)
 481                 return result;
 482
 483         if (!d)
 484                 return -ENODATA;
 485
 486         *data = d;
 487         return 0;
 488 }
 489
 490 /* --------------------------------------------------------------------------
 491                                 Event Management
 492    -------------------------------------------------------------------------- */
 493 int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
 494                               acpi_handle handle, acpi_ec_query_func func,
 495                               void *data)
 496 {
 497         struct acpi_ec_query_handler *handler =
 498             kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL);
 499         if (!handler)
 500                 return -ENOMEM;
 501
 502         handler->query_bit = query_bit;
 503         handler->handle = handle;
 504         handler->func = func;
 505         handler->data = data;
 506         mutex_lock(&ec->lock);
 507         list_add(&handler->node, &ec->list);
 508         mutex_unlock(&ec->lock);
 509         return 0;
 510 }
 511
 512 EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler);
 513
 514 void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit)
 515 {
 516         struct acpi_ec_query_handler *handler, *tmp;
 517         mutex_lock(&ec->lock);
 518         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
 519                 if (query_bit == handler->query_bit) {
 520                         list_del(&handler->node);
 521                         kfree(handler);
 522                 }
 523         }
 524         mutex_unlock(&ec->lock);
 525 }
 526
 527 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler);
 528
 529 static void acpi_ec_gpe_query(void *ec_cxt)
 530 {
 531         struct acpi_ec *ec = ec_cxt;
 532         u8 value = 0;
 533         struct acpi_ec_query_handler *handler, copy;
 534
 535         if (!ec || acpi_ec_query(ec, &value))
 536                 return;
 537         mutex_lock(&ec->lock);
 538         list_for_each_entry(handler, &ec->list, node) {
 539                 if (value == handler->query_bit) {
 540                         /* have custom handler for this bit */
 541                         memcpy(&copy, handler, sizeof(copy));
 542                         mutex_unlock(&ec->lock);
 543                         if (copy.func) {
 544                                 copy.func(copy.data);
 545                         } else if (copy.handle) {
 546                                 acpi_evaluate_object(copy.handle, NULL, NULL, NULL);
 547                         }
 548                         return;
 549                 }
 550         }
 551         mutex_unlock(&ec->lock);
 552 }
 553
 554 static u32 acpi_ec_gpe_handler(void *data)
 555 {
 556         struct acpi_ec *ec = data;
 557         u8 status;
 558
 559         pr_debug(PREFIX "~~~> interrupt\n");
 560         status = acpi_ec_read_status(ec);
 561
 562         gpe_transaction(ec, status);
 563         if (ec_transaction_done(ec) && (status & ACPI_EC_FLAG_IBF) == 0)
 564                 wake_up(&ec->wait);
 565
 566         ec_check_sci(ec, status);
 567         if (!test_bit(EC_FLAGS_GPE_MODE, &ec->flags) &&
 568             !test_bit(EC_FLAGS_NO_GPE, &ec->flags)) {
 569                 /* this is non-query, must be confirmation */
 570                 if (!test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
 571                         if (printk_ratelimit())
 572                                 pr_info(PREFIX "non-query interrupt received,"
 573                                         " switching to interrupt mode\n");
 574                 } else {
 575                         /* hush, STORM switches the mode every transaction */
 576                         pr_debug(PREFIX "non-query interrupt received,"
 577                                 " switching to interrupt mode\n");
 578                 }
 579                 set_bit(EC_FLAGS_GPE_MODE, &ec->flags);
 580         }
 581         return ACPI_INTERRUPT_HANDLED;
 582 }
 583
 584 /* --------------------------------------------------------------------------
 585                              Address Space Management
 586    -------------------------------------------------------------------------- */
 587
 588 static acpi_status
 589 acpi_ec_space_handler(u32 function, acpi_physical_address address,
 590                       u32 bits, acpi_integer *value,
 591                       void *handler_context, void *region_context)
 592 {
 593         struct acpi_ec *ec = handler_context;
 594         int result = 0, i;
 595         u8 temp = 0;
 596
 597         if ((address > 0xFF) || !value || !handler_context)
 598                 return AE_BAD_PARAMETER;
 599
 600         if (function != ACPI_READ && function != ACPI_WRITE)
 601                 return AE_BAD_PARAMETER;
 602
 603         if (bits != 8 && acpi_strict)
 604                 return AE_BAD_PARAMETER;
 605
 606         acpi_ec_burst_enable(ec);
 607
 608         if (function == ACPI_READ) {
 609                 result = acpi_ec_read(ec, address, &temp);
 610                 *value = temp;
 611         } else {
 612                 temp = 0xff & (*value);
 613                 result = acpi_ec_write(ec, address, temp);
 614         }
 615
 616         for (i = 8; unlikely(bits - i > 0); i += 8) {
 617                 ++address;
 618                 if (function == ACPI_READ) {
 619                         result = acpi_ec_read(ec, address, &temp);
 620                         (*value) |= ((acpi_integer)temp) << i;
 621                 } else {
 622                         temp = 0xff & ((*value) >> i);
 623                         result = acpi_ec_write(ec, address, temp);
 624                 }
 625         }
 626
 627         acpi_ec_burst_disable(ec);
 628
 629         switch (result) {
 630         case -EINVAL:
 631                 return AE_BAD_PARAMETER;
 632                 break;
 633         case -ENODEV:
 634                 return AE_NOT_FOUND;
 635                 break;
 636         case -ETIME:
 637                 return AE_TIME;
 638                 break;
 639         default:
 640                 return AE_OK;
 641         }
 642 }
 643
 644 /* --------------------------------------------------------------------------
 645                               FS Interface (/proc)
 646    -------------------------------------------------------------------------- */
 647
 648 static struct proc_dir_entry *acpi_ec_dir;
 649
 650 static int acpi_ec_read_info(struct seq_file *seq, void *offset)
 651 {
 652         struct acpi_ec *ec = seq->private;
 653
 654         if (!ec)
 655                 goto end;
 656
 657         seq_printf(seq, "gpe:\t\t\t0x%02x\n", (u32) ec->gpe);
 658         seq_printf(seq, "ports:\t\t\t0x%02x, 0x%02x\n",
 659                    (unsigned)ec->command_addr, (unsigned)ec->data_addr);
 660         seq_printf(seq, "use global lock:\t%s\n",
 661                    ec->global_lock ? "yes" : "no");
 662       end:
 663         return 0;
 664 }
 665
 666 static int acpi_ec_info_open_fs(struct inode *inode, struct file *file)
 667 {
 668         return single_open(file, acpi_ec_read_info, PDE(inode)->data);
 669 }
 670
 671 static struct file_operations acpi_ec_info_ops = {
 672         .open = acpi_ec_info_open_fs,
 673         .read = seq_read,
 674         .llseek = seq_lseek,
 675         .release = single_release,
 676         .owner = THIS_MODULE,
 677 };
 678
 679 static int acpi_ec_add_fs(struct acpi_device *device)
 680 {
 681         struct proc_dir_entry *entry = NULL;
 682
 683         if (!acpi_device_dir(device)) {
 684                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
 685                                                      acpi_ec_dir);
 686                 if (!acpi_device_dir(device))
 687                         return -ENODEV;
 688         }
 689
 690         entry = proc_create_data(ACPI_EC_FILE_INFO, S_IRUGO,
 691                                  acpi_device_dir(device),
 692                                  &acpi_ec_info_ops, acpi_driver_data(device));
 693         if (!entry)
 694                 return -ENODEV;
 695         return 0;
 696 }
 697
 698 static int acpi_ec_remove_fs(struct acpi_device *device)
 699 {
 700
 701         if (acpi_device_dir(device)) {
 702                 remove_proc_entry(ACPI_EC_FILE_INFO, acpi_device_dir(device));
 703                 remove_proc_entry(acpi_device_bid(device), acpi_ec_dir);
 704                 acpi_device_dir(device) = NULL;
 705         }
 706
 707         return 0;
 708 }
 709
 710 /* --------------------------------------------------------------------------
 711                                Driver Interface
 712    -------------------------------------------------------------------------- */
 713 static acpi_status
 714 ec_parse_io_ports(struct acpi_resource *resource, void *context);
 715
 716 static struct acpi_ec *make_acpi_ec(void)
 717 {
 718         struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
 719         if (!ec)
 720                 return NULL;
 721         ec->flags = 1 << EC_FLAGS_QUERY_PENDING;
 722         mutex_init(&ec->lock);
 723         init_waitqueue_head(&ec->wait);
 724         INIT_LIST_HEAD(&ec->list);
 725         spin_lock_init(&ec->curr_lock);
 726         return ec;
 727 }
 728
 729 static acpi_status
 730 acpi_ec_register_query_methods(acpi_handle handle, u32 level,
 731                                void *context, void **return_value)
 732 {
 733         struct acpi_namespace_node *node = handle;
 734         struct acpi_ec *ec = context;
 735         int value = 0;
 736         if (sscanf(node->name.ascii, "_Q%x", &value) == 1) {
 737                 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL);
 738         }
 739         return AE_OK;
 740 }
 741
 742 static acpi_status
 743 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
 744 {
 745         acpi_status status;
 746         unsigned long long tmp;
 747
 748         struct acpi_ec *ec = context;
 749         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
 750                                      ec_parse_io_ports, ec);
 751         if (ACPI_FAILURE(status))
 752                 return status;
 753
 754         /* Get GPE bit assignment (EC events). */
 755         /* TODO: Add support for _GPE returning a package */
 756         status = acpi_evaluate_integer(handle, "_GPE", NULL, &tmp);
 757         if (ACPI_FAILURE(status))
 758                 return status;
 759         ec->gpe = tmp;
 760         /* Use the global lock for all EC transactions? */
 761         acpi_evaluate_integer(handle, "_GLK", NULL, &tmp);
 762         ec->global_lock = tmp;
 763         ec->handle = handle;
 764         return AE_CTRL_TERMINATE;
 765 }
 766
 767 static void ec_remove_handlers(struct acpi_ec *ec)
 768 {
 769         if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle,
 770                                 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler)))
 771                 pr_err(PREFIX "failed to remove space handler\n");
 772         if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe,
 773                                 &acpi_ec_gpe_handler)))
 774                 pr_err(PREFIX "failed to remove gpe handler\n");
 775         clear_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
 776 }
 777
 778 static int acpi_ec_add(struct acpi_device *device)
 779 {
 780         struct acpi_ec *ec = NULL;
 781
 782         if (!device)
 783                 return -EINVAL;
 784         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
 785         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
 786
 787         /* Check for boot EC */
 788         if (boot_ec &&
 789             (boot_ec->handle == device->handle ||
 790              boot_ec->handle == ACPI_ROOT_OBJECT)) {
 791                 ec = boot_ec;
 792                 boot_ec = NULL;
 793         } else {
 794                 ec = make_acpi_ec();
 795                 if (!ec)
 796                         return -ENOMEM;
 797                 if (ec_parse_device(device->handle, 0, ec, NULL) !=
 798                     AE_CTRL_TERMINATE) {
 799                         kfree(ec);
 800                         return -EINVAL;
 801                 }
 802         }
 803
 804         ec->handle = device->handle;
 805
 806         /* Find and register all query methods */
 807         acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1,
 808                             acpi_ec_register_query_methods, ec, NULL);
 809
 810         if (!first_ec)
 811                 first_ec = ec;
 812         device->driver_data = ec;
 813         acpi_ec_add_fs(device);
 814         pr_info(PREFIX "GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n",
 815                           ec->gpe, ec->command_addr, ec->data_addr);
 816         pr_info(PREFIX "driver started in %s mode\n",
 817                 (test_bit(EC_FLAGS_GPE_MODE, &ec->flags))?"interrupt":"poll");
 818         return 0;
 819 }
 820
 821 static int acpi_ec_remove(struct acpi_device *device, int type)
 822 {
 823         struct acpi_ec *ec;
 824         struct acpi_ec_query_handler *handler, *tmp;
 825
 826         if (!device)
 827                 return -EINVAL;
 828
 829         ec = acpi_driver_data(device);
 830         mutex_lock(&ec->lock);
 831         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
 832                 list_del(&handler->node);
 833                 kfree(handler);
 834         }
 835         mutex_unlock(&ec->lock);
 836         acpi_ec_remove_fs(device);
 837         device->driver_data = NULL;
 838         if (ec == first_ec)
 839                 first_ec = NULL;
 840         kfree(ec);
 841         return 0;
 842 }
 843
 844 static acpi_status
 845 ec_parse_io_ports(struct acpi_resource *resource, void *context)
 846 {
 847         struct acpi_ec *ec = context;
 848
 849         if (resource->type != ACPI_RESOURCE_TYPE_IO)
 850                 return AE_OK;
 851
 852         /*
 853          * The first address region returned is the data port, and
 854          * the second address region returned is the status/command
 855          * port.
 856          */
 857         if (ec->data_addr == 0)
 858                 ec->data_addr = resource->data.io.minimum;
 859         else if (ec->command_addr == 0)
 860                 ec->command_addr = resource->data.io.minimum;
 861         else
 862                 return AE_CTRL_TERMINATE;
 863
 864         return AE_OK;
 865 }
 866
 867 static int ec_install_handlers(struct acpi_ec *ec)
 868 {
 869         acpi_status status;
 870         if (test_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags))
 871                 return 0;
 872         status = acpi_install_gpe_handler(NULL, ec->gpe,
 873                                   ACPI_GPE_EDGE_TRIGGERED,
 874                                   &acpi_ec_gpe_handler, ec);
 875         if (ACPI_FAILURE(status))
 876                 return -ENODEV;
 877         acpi_set_gpe_type(NULL, ec->gpe, ACPI_GPE_TYPE_RUNTIME);
 878         acpi_enable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
 879         status = acpi_install_address_space_handler(ec->handle,
 880                                                     ACPI_ADR_SPACE_EC,
 881                                                     &acpi_ec_space_handler,
 882                                                     NULL, ec);
 883         if (ACPI_FAILURE(status)) {
 884                 if (status == AE_NOT_FOUND) {
 885                         /*
 886                          * Maybe OS fails in evaluating the _REG object.
 887                          * The AE_NOT_FOUND error will be ignored and OS
 888                          * continue to initialize EC.
 889                          */
 890                         printk(KERN_ERR "Fail in evaluating the _REG object"
 891                                 " of EC device. Broken bios is suspected.\n");
 892                 } else {
 893                         acpi_remove_gpe_handler(NULL, ec->gpe,
 894                                 &acpi_ec_gpe_handler);
 895                         return -ENODEV;
 896                 }
 897         }
 898
 899         set_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
 900         return 0;
 901 }
 902
 903 static int acpi_ec_start(struct acpi_device *device)
 904 {
 905         struct acpi_ec *ec;
 906         int ret = 0;
 907
 908         if (!device)
 909                 return -EINVAL;
 910
 911         ec = acpi_driver_data(device);
 912
 913         if (!ec)
 914                 return -EINVAL;
 915
 916         ret = ec_install_handlers(ec);
 917
 918         /* EC is fully operational, allow queries */
 919         clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
 920         return ret;
 921 }
 922
 923 static int acpi_ec_stop(struct acpi_device *device, int type)
 924 {
 925         struct acpi_ec *ec;
 926         if (!device)
 927                 return -EINVAL;
 928         ec = acpi_driver_data(device);
 929         if (!ec)
 930                 return -EINVAL;
 931         ec_remove_handlers(ec);
 932
 933         return 0;
 934 }
 935
 936 int __init acpi_boot_ec_enable(void)
 937 {
 938         if (!boot_ec || test_bit(EC_FLAGS_HANDLERS_INSTALLED, &boot_ec->flags))
 939                 return 0;
 940         if (!ec_install_handlers(boot_ec)) {
 941                 first_ec = boot_ec;
 942                 return 0;
 943         }
 944         return -EFAULT;
 945 }
 946
 947 static const struct acpi_device_id ec_device_ids[] = {
 948         {"PNP0C09", 0},
 949         {"", 0},
 950 };
 951
 952 int __init acpi_ec_ecdt_probe(void)
 953 {
 954         int ret;
 955         acpi_status status;
 956         struct acpi_table_ecdt *ecdt_ptr;
 957
 958         boot_ec = make_acpi_ec();
 959         if (!boot_ec)
 960                 return -ENOMEM;
 961         /*
 962          * Generate a boot ec context
 963          */
 964         status = acpi_get_table(ACPI_SIG_ECDT, 1,
 965                                 (struct acpi_table_header **)&ecdt_ptr);
 966         if (ACPI_SUCCESS(status)) {
 967                 pr_info(PREFIX "EC description table is found, configuring boot EC\n");
 968                 boot_ec->command_addr = ecdt_ptr->control.address;
 969                 boot_ec->data_addr = ecdt_ptr->data.address;
 970                 if (dmi_check_system(ec_dmi_table)) {
 971                         /*
 972                          * If the board falls into ec_dmi_table, it means
 973                          * that ECDT table gives the incorrect command/status
 974                          * & data I/O address. Just fix it.
 975                          */
 976                         boot_ec->data_addr = ecdt_ptr->control.address;
 977                         boot_ec->command_addr = ecdt_ptr->data.address;
 978                 }
 979                 boot_ec->gpe = ecdt_ptr->gpe;
 980                 boot_ec->handle = ACPI_ROOT_OBJECT;
 981                 acpi_get_handle(ACPI_ROOT_OBJECT, ecdt_ptr->id, &boot_ec->handle);
 982         } else {
 983                 /* This workaround is needed only on some broken machines,
 984                  * which require early EC, but fail to provide ECDT */
 985                 acpi_handle x;
 986                 printk(KERN_DEBUG PREFIX "Look up EC in DSDT\n");
 987                 status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device,
 988                                                 boot_ec, NULL);
 989                 /* Check that acpi_get_devices actually find something */
 990                 if (ACPI_FAILURE(status) || !boot_ec->handle)
 991                         goto error;
 992                 /* We really need to limit this workaround, the only ASUS,
 993                  * which needs it, has fake EC._INI method, so use it as flag.
 994                  * Keep boot_ec struct as it will be needed soon.
 995                  */
 996                 if (ACPI_FAILURE(acpi_get_handle(boot_ec->handle, "_INI", &x)))
 997                         return -ENODEV;
 998         }
 999
1000         ret = ec_install_handlers(boot_ec);
1001         if (!ret) {
1002                 first_ec = boot_ec;
1003                 return 0;
1004         }
1005       error:
1006         kfree(boot_ec);
1007         boot_ec = NULL;
1008         return -ENODEV;
1009 }
1010
1011 static int acpi_ec_suspend(struct acpi_device *device, pm_message_t state)
1012 {
1013         struct acpi_ec *ec = acpi_driver_data(device);
1014         /* Stop using GPE */
1015         set_bit(EC_FLAGS_NO_GPE, &ec->flags);
1016         clear_bit(EC_FLAGS_GPE_MODE, &ec->flags);
1017         acpi_disable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
1018         return 0;
1019 }
1020
1021 static int acpi_ec_resume(struct acpi_device *device)
1022 {
1023         struct acpi_ec *ec = acpi_driver_data(device);
1024         /* Enable use of GPE back */
1025         clear_bit(EC_FLAGS_NO_GPE, &ec->flags);
1026         acpi_enable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
1027         return 0;
1028 }
1029
1030 static struct acpi_driver acpi_ec_driver = {
1031         .name = "ec",
1032         .class = ACPI_EC_CLASS,
1033         .ids = ec_device_ids,
1034         .ops = {
1035                 .add = acpi_ec_add,
1036                 .remove = acpi_ec_remove,
1037                 .start = acpi_ec_start,
1038                 .stop = acpi_ec_stop,
1039                 .suspend = acpi_ec_suspend,
1040                 .resume = acpi_ec_resume,
1041                 },
1042 };
1043
1044 static int __init acpi_ec_init(void)
1045 {
1046         int result = 0;
1047
1048         if (acpi_disabled)
1049                 return 0;
1050
1051         acpi_ec_dir = proc_mkdir(ACPI_EC_CLASS, acpi_root_dir);
1052         if (!acpi_ec_dir)
1053                 return -ENODEV;
1054
1055         /* Now register the driver for the EC */
1056         result = acpi_bus_register_driver(&acpi_ec_driver);
1057         if (result < 0) {
1058                 remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1059                 return -ENODEV;
1060         }
1061
1062         return result;
1063 }
1064
1065 subsys_initcall(acpi_ec_init);
1066
1067 /* EC driver currently not unloadable */
1068 #if 0
1069 static void __exit acpi_ec_exit(void)
1070 {
1071
1072         acpi_bus_unregister_driver(&acpi_ec_driver);
1073
1074         remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1075
1076         return;
1077 }
1078 #endif  /* 0 */