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   1 /*
   2  *  ec.c - ACPI Embedded Controller Driver (v2.0)
   3  *
   4  *  Copyright (C) 2006, 2007 Alexey Starikovskiy <alexey.y.starikovskiy@intel.com>
   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 print outs*/
  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 <asm/io.h>
  42 #include <acpi/acpi_bus.h>
  43 #include <acpi/acpi_drivers.h>
  44 #include <acpi/actypes.h>
  45
  46 #define ACPI_EC_CLASS                   "embedded_controller"
  47 #define ACPI_EC_DEVICE_NAME             "Embedded Controller"
  48 #define ACPI_EC_FILE_INFO               "info"
  49
  50 #undef PREFIX
  51 #define PREFIX                          "ACPI: EC: "
  52
  53 /* EC status register */
  54 #define ACPI_EC_FLAG_OBF        0x01    /* Output buffer full */
  55 #define ACPI_EC_FLAG_IBF        0x02    /* Input buffer full */
  56 #define ACPI_EC_FLAG_BURST      0x10    /* burst mode */
  57 #define ACPI_EC_FLAG_SCI        0x20    /* EC-SCI occurred */
  58
  59 /* EC commands */
  60 enum ec_command {
  61         ACPI_EC_COMMAND_READ = 0x80,
  62         ACPI_EC_COMMAND_WRITE = 0x81,
  63         ACPI_EC_BURST_ENABLE = 0x82,
  64         ACPI_EC_BURST_DISABLE = 0x83,
  65         ACPI_EC_COMMAND_QUERY = 0x84,
  66 };
  67
  68 /* EC events */
  69 enum ec_event {
  70         ACPI_EC_EVENT_OBF_1 = 1,        /* Output buffer full */
  71         ACPI_EC_EVENT_IBF_0,            /* Input buffer empty */
  72 };
  73
  74 #define ACPI_EC_DELAY           500     /* Wait 500ms max. during EC ops */
  75 #define ACPI_EC_UDELAY_GLK      1000    /* Wait 1ms max. to get global lock */
  76 #define ACPI_EC_UDELAY          100     /* Wait 100us before polling EC again */
  77
  78 enum {
  79         EC_FLAGS_WAIT_GPE = 0,          /* Don't check status until GPE arrives */
  80         EC_FLAGS_QUERY_PENDING,         /* Query is pending */
  81         EC_FLAGS_GPE_MODE,              /* Expect GPE to be sent for status change */
  82         EC_FLAGS_NO_GPE,                /* Don't use GPE mode */
  83         EC_FLAGS_RESCHEDULE_POLL        /* Re-schedule poll */
  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 static struct acpi_ec {
  99         acpi_handle handle;
 100         unsigned long gpe;
 101         unsigned long command_addr;
 102         unsigned long data_addr;
 103         unsigned long global_lock;
 104         unsigned long flags;
 105         struct mutex lock;
 106         wait_queue_head_t wait;
 107         struct list_head list;
 108         struct delayed_work work;
 109         atomic_t irq_count;
 110         u8 handlers_installed;
 111 } *boot_ec, *first_ec;
 112
 113 /* --------------------------------------------------------------------------
 114                              Transaction Management
 115    -------------------------------------------------------------------------- */
 116
 117 static inline u8 acpi_ec_read_status(struct acpi_ec *ec)
 118 {
 119         u8 x = inb(ec->command_addr);
 120         pr_debug(PREFIX "---> status = 0x%2.2x\n", x);
 121         return x;
 122 }
 123
 124 static inline u8 acpi_ec_read_data(struct acpi_ec *ec)
 125 {
 126         u8 x = inb(ec->data_addr);
 127         pr_debug(PREFIX "---> data = 0x%2.2x\n", x);
 128         return inb(ec->data_addr);
 129 }
 130
 131 static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command)
 132 {
 133         pr_debug(PREFIX "<--- command = 0x%2.2x\n", command);
 134         outb(command, ec->command_addr);
 135 }
 136
 137 static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data)
 138 {
 139         pr_debug(PREFIX "<--- data = 0x%2.2x\n", data);
 140         outb(data, ec->data_addr);
 141 }
 142
 143 static inline int acpi_ec_check_status(struct acpi_ec *ec, enum ec_event event)
 144 {
 145         if (test_bit(EC_FLAGS_WAIT_GPE, &ec->flags))
 146                 return 0;
 147         if (event == ACPI_EC_EVENT_OBF_1) {
 148                 if (acpi_ec_read_status(ec) & ACPI_EC_FLAG_OBF)
 149                         return 1;
 150         } else if (event == ACPI_EC_EVENT_IBF_0) {
 151                 if (!(acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF))
 152                         return 1;
 153         }
 154
 155         return 0;
 156 }
 157
 158 static void ec_schedule_ec_poll(struct acpi_ec *ec)
 159 {
 160         if (test_bit(EC_FLAGS_RESCHEDULE_POLL, &ec->flags))
 161                 schedule_delayed_work(&ec->work,
 162                                       msecs_to_jiffies(ACPI_EC_DELAY));
 163 }
 164
 165 static void ec_switch_to_poll_mode(struct acpi_ec *ec)
 166 {
 167         set_bit(EC_FLAGS_NO_GPE, &ec->flags);
 168         clear_bit(EC_FLAGS_GPE_MODE, &ec->flags);
 169         acpi_disable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
 170         set_bit(EC_FLAGS_RESCHEDULE_POLL, &ec->flags);
 171 }
 172
 173 static int acpi_ec_wait(struct acpi_ec *ec, enum ec_event event, int force_poll)
 174 {
 175         atomic_set(&ec->irq_count, 0);
 176         if (likely(test_bit(EC_FLAGS_GPE_MODE, &ec->flags)) &&
 177             likely(!force_poll)) {
 178                 if (wait_event_timeout(ec->wait, acpi_ec_check_status(ec, event),
 179                                        msecs_to_jiffies(ACPI_EC_DELAY)))
 180                         return 0;
 181                 clear_bit(EC_FLAGS_WAIT_GPE, &ec->flags);
 182                 if (acpi_ec_check_status(ec, event)) {
 183                         /* missing GPEs, switch back to poll mode */
 184                         if (printk_ratelimit())
 185                                 pr_info(PREFIX "missing confirmations, "
 186                                                 "switch off interrupt mode.\n");
 187                         ec_switch_to_poll_mode(ec);
 188                         ec_schedule_ec_poll(ec);
 189                         return 0;
 190                 }
 191         } else {
 192                 unsigned long delay = jiffies + msecs_to_jiffies(ACPI_EC_DELAY);
 193                 clear_bit(EC_FLAGS_WAIT_GPE, &ec->flags);
 194                 while (time_before(jiffies, delay)) {
 195                         if (acpi_ec_check_status(ec, event))
 196                                 return 0;
 197                         udelay(ACPI_EC_UDELAY);
 198                 }
 199         }
 200         pr_err(PREFIX "acpi_ec_wait timeout, status = 0x%2.2x, event = %s\n",
 201                 acpi_ec_read_status(ec),
 202                 (event == ACPI_EC_EVENT_OBF_1) ? "\"b0=1\"" : "\"b1=0\"");
 203         return -ETIME;
 204 }
 205
 206 static int acpi_ec_transaction_unlocked(struct acpi_ec *ec, u8 command,
 207                                         const u8 * wdata, unsigned wdata_len,
 208                                         u8 * rdata, unsigned rdata_len,
 209                                         int force_poll)
 210 {
 211         int result = 0;
 212         set_bit(EC_FLAGS_WAIT_GPE, &ec->flags);
 213         pr_debug(PREFIX "transaction start\n");
 214         acpi_ec_write_cmd(ec, command);
 215         for (; wdata_len > 0; --wdata_len) {
 216                 result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0, force_poll);
 217                 if (result) {
 218                         pr_err(PREFIX
 219                                "write_cmd timeout, command = %d\n", command);
 220                         goto end;
 221                 }
 222                 set_bit(EC_FLAGS_WAIT_GPE, &ec->flags);
 223                 acpi_ec_write_data(ec, *(wdata++));
 224         }
 225
 226         if (!rdata_len) {
 227                 result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0, force_poll);
 228                 if (result) {
 229                         pr_err(PREFIX
 230                                "finish-write timeout, command = %d\n", command);
 231                         goto end;
 232                 }
 233         } else if (command == ACPI_EC_COMMAND_QUERY)
 234                 clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
 235
 236         for (; rdata_len > 0; --rdata_len) {
 237                 result = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF_1, force_poll);
 238                 if (result) {
 239                         pr_err(PREFIX "read timeout, command = %d\n", command);
 240                         goto end;
 241                 }
 242                 /* Don't expect GPE after last read */
 243                 if (rdata_len > 1)
 244                         set_bit(EC_FLAGS_WAIT_GPE, &ec->flags);
 245                 *(rdata++) = acpi_ec_read_data(ec);
 246         }
 247       end:
 248         pr_debug(PREFIX "transaction end\n");
 249         return result;
 250 }
 251
 252 static int acpi_ec_transaction(struct acpi_ec *ec, u8 command,
 253                                const u8 * wdata, unsigned wdata_len,
 254                                u8 * rdata, unsigned rdata_len,
 255                                int force_poll)
 256 {
 257         int status;
 258         u32 glk;
 259
 260         if (!ec || (wdata_len && !wdata) || (rdata_len && !rdata))
 261                 return -EINVAL;
 262
 263         if (rdata)
 264                 memset(rdata, 0, rdata_len);
 265
 266         mutex_lock(&ec->lock);
 267         if (ec->global_lock) {
 268                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 269                 if (ACPI_FAILURE(status)) {
 270                         mutex_unlock(&ec->lock);
 271                         return -ENODEV;
 272                 }
 273         }
 274
 275         status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0, 0);
 276         if (status) {
 277                 pr_err(PREFIX "input buffer is not empty, "
 278                                 "aborting transaction\n");
 279                 goto end;
 280         }
 281
 282         status = acpi_ec_transaction_unlocked(ec, command,
 283                                               wdata, wdata_len,
 284                                               rdata, rdata_len,
 285                                               force_poll);
 286
 287       end:
 288
 289         if (ec->global_lock)
 290                 acpi_release_global_lock(glk);
 291         mutex_unlock(&ec->lock);
 292
 293         return status;
 294 }
 295
 296 /*
 297  * Note: samsung nv5000 doesn't work with ec burst mode.
 298  * http://bugzilla.kernel.org/show_bug.cgi?id=4980
 299  */
 300 int acpi_ec_burst_enable(struct acpi_ec *ec)
 301 {
 302         u8 d;
 303         return acpi_ec_transaction(ec, ACPI_EC_BURST_ENABLE, NULL, 0, &d, 1, 0);
 304 }
 305
 306 int acpi_ec_burst_disable(struct acpi_ec *ec)
 307 {
 308         return acpi_ec_transaction(ec, ACPI_EC_BURST_DISABLE, NULL, 0, NULL, 0, 0);
 309 }
 310
 311 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 * data)
 312 {
 313         int result;
 314         u8 d;
 315
 316         result = acpi_ec_transaction(ec, ACPI_EC_COMMAND_READ,
 317                                      &address, 1, &d, 1, 0);
 318         *data = d;
 319         return result;
 320 }
 321
 322 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
 323 {
 324         u8 wdata[2] = { address, data };
 325         return acpi_ec_transaction(ec, ACPI_EC_COMMAND_WRITE,
 326                                    wdata, 2, NULL, 0, 0);
 327 }
 328
 329 /*
 330  * Externally callable EC access functions. For now, assume 1 EC only
 331  */
 332 int ec_burst_enable(void)
 333 {
 334         if (!first_ec)
 335                 return -ENODEV;
 336         return acpi_ec_burst_enable(first_ec);
 337 }
 338
 339 EXPORT_SYMBOL(ec_burst_enable);
 340
 341 int ec_burst_disable(void)
 342 {
 343         if (!first_ec)
 344                 return -ENODEV;
 345         return acpi_ec_burst_disable(first_ec);
 346 }
 347
 348 EXPORT_SYMBOL(ec_burst_disable);
 349
 350 int ec_read(u8 addr, u8 * val)
 351 {
 352         int err;
 353         u8 temp_data;
 354
 355         if (!first_ec)
 356                 return -ENODEV;
 357
 358         err = acpi_ec_read(first_ec, addr, &temp_data);
 359
 360         if (!err) {
 361                 *val = temp_data;
 362                 return 0;
 363         } else
 364                 return err;
 365 }
 366
 367 EXPORT_SYMBOL(ec_read);
 368
 369 int ec_write(u8 addr, u8 val)
 370 {
 371         int err;
 372
 373         if (!first_ec)
 374                 return -ENODEV;
 375
 376         err = acpi_ec_write(first_ec, addr, val);
 377
 378         return err;
 379 }
 380
 381 EXPORT_SYMBOL(ec_write);
 382
 383 int ec_transaction(u8 command,
 384                    const u8 * wdata, unsigned wdata_len,
 385                    u8 * rdata, unsigned rdata_len,
 386                    int force_poll)
 387 {
 388         if (!first_ec)
 389                 return -ENODEV;
 390
 391         return acpi_ec_transaction(first_ec, command, wdata,
 392                                    wdata_len, rdata, rdata_len,
 393                                    force_poll);
 394 }
 395
 396 EXPORT_SYMBOL(ec_transaction);
 397
 398 static int acpi_ec_query(struct acpi_ec *ec, u8 * data)
 399 {
 400         int result;
 401         u8 d;
 402
 403         if (!ec || !data)
 404                 return -EINVAL;
 405
 406         /*
 407          * Query the EC to find out which _Qxx method we need to evaluate.
 408          * Note that successful completion of the query causes the ACPI_EC_SCI
 409          * bit to be cleared (and thus clearing the interrupt source).
 410          */
 411
 412         result = acpi_ec_transaction(ec, ACPI_EC_COMMAND_QUERY, NULL, 0, &d, 1, 0);
 413         if (result)
 414                 return result;
 415
 416         if (!d)
 417                 return -ENODATA;
 418
 419         *data = d;
 420         return 0;
 421 }
 422
 423 /* --------------------------------------------------------------------------
 424                                 Event Management
 425    -------------------------------------------------------------------------- */
 426 int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
 427                               acpi_handle handle, acpi_ec_query_func func,
 428                               void *data)
 429 {
 430         struct acpi_ec_query_handler *handler =
 431             kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL);
 432         if (!handler)
 433                 return -ENOMEM;
 434
 435         handler->query_bit = query_bit;
 436         handler->handle = handle;
 437         handler->func = func;
 438         handler->data = data;
 439         mutex_lock(&ec->lock);
 440         list_add(&handler->node, &ec->list);
 441         mutex_unlock(&ec->lock);
 442         return 0;
 443 }
 444
 445 EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler);
 446
 447 void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit)
 448 {
 449         struct acpi_ec_query_handler *handler, *tmp;
 450         mutex_lock(&ec->lock);
 451         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
 452                 if (query_bit == handler->query_bit) {
 453                         list_del(&handler->node);
 454                         kfree(handler);
 455                 }
 456         }
 457         mutex_unlock(&ec->lock);
 458 }
 459
 460 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler);
 461
 462 static void acpi_ec_gpe_query(void *ec_cxt)
 463 {
 464         struct acpi_ec *ec = ec_cxt;
 465         u8 value = 0;
 466         struct acpi_ec_query_handler *handler, copy;
 467
 468         if (!ec || acpi_ec_query(ec, &value))
 469                 return;
 470         mutex_lock(&ec->lock);
 471         list_for_each_entry(handler, &ec->list, node) {
 472                 if (value == handler->query_bit) {
 473                         /* have custom handler for this bit */
 474                         memcpy(&copy, handler, sizeof(copy));
 475                         mutex_unlock(&ec->lock);
 476                         if (copy.func) {
 477                                 copy.func(copy.data);
 478                         } else if (copy.handle) {
 479                                 acpi_evaluate_object(copy.handle, NULL, NULL, NULL);
 480                         }
 481                         return;
 482                 }
 483         }
 484         mutex_unlock(&ec->lock);
 485 }
 486
 487 static u32 acpi_ec_gpe_handler(void *data)
 488 {
 489         acpi_status status = AE_OK;
 490         struct acpi_ec *ec = data;
 491         u8 state = acpi_ec_read_status(ec);
 492
 493         pr_debug(PREFIX "~~~> interrupt\n");
 494         atomic_inc(&ec->irq_count);
 495         if (atomic_read(&ec->irq_count) > 5) {
 496                 pr_err(PREFIX "GPE storm detected, disabling EC GPE\n");
 497                 ec_switch_to_poll_mode(ec);
 498                 goto end;
 499         }
 500         clear_bit(EC_FLAGS_WAIT_GPE, &ec->flags);
 501         if (test_bit(EC_FLAGS_GPE_MODE, &ec->flags))
 502                 wake_up(&ec->wait);
 503
 504         if (state & ACPI_EC_FLAG_SCI) {
 505                 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags))
 506                         status = acpi_os_execute(OSL_EC_BURST_HANDLER,
 507                                 acpi_ec_gpe_query, ec);
 508         } else if (!test_bit(EC_FLAGS_GPE_MODE, &ec->flags) &&
 509                    !test_bit(EC_FLAGS_NO_GPE, &ec->flags) &&
 510                    in_interrupt()) {
 511                 /* this is non-query, must be confirmation */
 512                 if (printk_ratelimit())
 513                         pr_info(PREFIX "non-query interrupt received,"
 514                                 " switching to interrupt mode\n");
 515                 set_bit(EC_FLAGS_GPE_MODE, &ec->flags);
 516                 clear_bit(EC_FLAGS_RESCHEDULE_POLL, &ec->flags);
 517         }
 518 end:
 519         ec_schedule_ec_poll(ec);
 520         return ACPI_SUCCESS(status) ?
 521             ACPI_INTERRUPT_HANDLED : ACPI_INTERRUPT_NOT_HANDLED;
 522 }
 523
 524 static void do_ec_poll(struct work_struct *work)
 525 {
 526         struct acpi_ec *ec = container_of(work, struct acpi_ec, work.work);
 527         atomic_set(&ec->irq_count, 0);
 528         (void)acpi_ec_gpe_handler(ec);
 529 }
 530
 531 /* --------------------------------------------------------------------------
 532                              Address Space Management
 533    -------------------------------------------------------------------------- */
 534
 535 static acpi_status
 536 acpi_ec_space_setup(acpi_handle region_handle,
 537                     u32 function, void *handler_context, void **return_context)
 538 {
 539         /*
 540          * The EC object is in the handler context and is needed
 541          * when calling the acpi_ec_space_handler.
 542          */
 543         *return_context = (function != ACPI_REGION_DEACTIVATE) ?
 544             handler_context : NULL;
 545
 546         return AE_OK;
 547 }
 548
 549 static acpi_status
 550 acpi_ec_space_handler(u32 function, acpi_physical_address address,
 551                       u32 bits, acpi_integer *value,
 552                       void *handler_context, void *region_context)
 553 {
 554         struct acpi_ec *ec = handler_context;
 555         int result = 0, i;
 556         u8 temp = 0;
 557
 558         if ((address > 0xFF) || !value || !handler_context)
 559                 return AE_BAD_PARAMETER;
 560
 561         if (function != ACPI_READ && function != ACPI_WRITE)
 562                 return AE_BAD_PARAMETER;
 563
 564         if (bits != 8 && acpi_strict)
 565                 return AE_BAD_PARAMETER;
 566
 567         acpi_ec_burst_enable(ec);
 568
 569         if (function == ACPI_READ) {
 570                 result = acpi_ec_read(ec, address, &temp);
 571                 *value = temp;
 572         } else {
 573                 temp = 0xff & (*value);
 574                 result = acpi_ec_write(ec, address, temp);
 575         }
 576
 577         for (i = 8; unlikely(bits - i > 0); i += 8) {
 578                 ++address;
 579                 if (function == ACPI_READ) {
 580                         result = acpi_ec_read(ec, address, &temp);
 581                         (*value) |= ((acpi_integer)temp) << i;
 582                 } else {
 583                         temp = 0xff & ((*value) >> i);
 584                         result = acpi_ec_write(ec, address, temp);
 585                 }
 586         }
 587
 588         acpi_ec_burst_disable(ec);
 589
 590         switch (result) {
 591         case -EINVAL:
 592                 return AE_BAD_PARAMETER;
 593                 break;
 594         case -ENODEV:
 595                 return AE_NOT_FOUND;
 596                 break;
 597         case -ETIME:
 598                 return AE_TIME;
 599                 break;
 600         default:
 601                 return AE_OK;
 602         }
 603 }
 604
 605 /* --------------------------------------------------------------------------
 606                               FS Interface (/proc)
 607    -------------------------------------------------------------------------- */
 608
 609 static struct proc_dir_entry *acpi_ec_dir;
 610
 611 static int acpi_ec_read_info(struct seq_file *seq, void *offset)
 612 {
 613         struct acpi_ec *ec = seq->private;
 614
 615         if (!ec)
 616                 goto end;
 617
 618         seq_printf(seq, "gpe:\t\t\t0x%02x\n", (u32) ec->gpe);
 619         seq_printf(seq, "ports:\t\t\t0x%02x, 0x%02x\n",
 620                    (unsigned)ec->command_addr, (unsigned)ec->data_addr);
 621         seq_printf(seq, "use global lock:\t%s\n",
 622                    ec->global_lock ? "yes" : "no");
 623       end:
 624         return 0;
 625 }
 626
 627 static int acpi_ec_info_open_fs(struct inode *inode, struct file *file)
 628 {
 629         return single_open(file, acpi_ec_read_info, PDE(inode)->data);
 630 }
 631
 632 static struct file_operations acpi_ec_info_ops = {
 633         .open = acpi_ec_info_open_fs,
 634         .read = seq_read,
 635         .llseek = seq_lseek,
 636         .release = single_release,
 637         .owner = THIS_MODULE,
 638 };
 639
 640 static int acpi_ec_add_fs(struct acpi_device *device)
 641 {
 642         struct proc_dir_entry *entry = NULL;
 643
 644         if (!acpi_device_dir(device)) {
 645                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
 646                                                      acpi_ec_dir);
 647                 if (!acpi_device_dir(device))
 648                         return -ENODEV;
 649         }
 650
 651         entry = create_proc_entry(ACPI_EC_FILE_INFO, S_IRUGO,
 652                                   acpi_device_dir(device));
 653         if (!entry)
 654                 return -ENODEV;
 655         else {
 656                 entry->proc_fops = &acpi_ec_info_ops;
 657                 entry->data = acpi_driver_data(device);
 658                 entry->owner = THIS_MODULE;
 659         }
 660
 661         return 0;
 662 }
 663
 664 static int acpi_ec_remove_fs(struct acpi_device *device)
 665 {
 666
 667         if (acpi_device_dir(device)) {
 668                 remove_proc_entry(ACPI_EC_FILE_INFO, acpi_device_dir(device));
 669                 remove_proc_entry(acpi_device_bid(device), acpi_ec_dir);
 670                 acpi_device_dir(device) = NULL;
 671         }
 672
 673         return 0;
 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         INIT_DELAYED_WORK_DEFERRABLE(&ec->work, do_ec_poll);
 692         atomic_set(&ec->irq_count, 0);
 693         return ec;
 694 }
 695
 696 static acpi_status
 697 acpi_ec_register_query_methods(acpi_handle handle, u32 level,
 698                                void *context, void **return_value)
 699 {
 700         struct acpi_namespace_node *node = handle;
 701         struct acpi_ec *ec = context;
 702         int value = 0;
 703         if (sscanf(node->name.ascii, "_Q%x", &value) == 1) {
 704                 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL);
 705         }
 706         return AE_OK;
 707 }
 708
 709 static acpi_status
 710 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
 711 {
 712         acpi_status status;
 713
 714         struct acpi_ec *ec = context;
 715         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
 716                                      ec_parse_io_ports, ec);
 717         if (ACPI_FAILURE(status))
 718                 return status;
 719
 720         /* Get GPE bit assignment (EC events). */
 721         /* TODO: Add support for _GPE returning a package */
 722         status = acpi_evaluate_integer(handle, "_GPE", NULL, &ec->gpe);
 723         if (ACPI_FAILURE(status))
 724                 return status;
 725         /* Find and register all query methods */
 726         acpi_walk_namespace(ACPI_TYPE_METHOD, handle, 1,
 727                             acpi_ec_register_query_methods, ec, NULL);
 728         /* Use the global lock for all EC transactions? */
 729         acpi_evaluate_integer(handle, "_GLK", NULL, &ec->global_lock);
 730         ec->handle = handle;
 731         return AE_CTRL_TERMINATE;
 732 }
 733
 734 static void ec_poll_stop(struct acpi_ec *ec)
 735 {
 736         clear_bit(EC_FLAGS_RESCHEDULE_POLL, &ec->flags);
 737         cancel_delayed_work(&ec->work);
 738 }
 739
 740 static void ec_remove_handlers(struct acpi_ec *ec)
 741 {
 742         ec_poll_stop(ec);
 743         if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle,
 744                                 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler)))
 745                 pr_err(PREFIX "failed to remove space handler\n");
 746         if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe,
 747                                 &acpi_ec_gpe_handler)))
 748                 pr_err(PREFIX "failed to remove gpe handler\n");
 749         ec->handlers_installed = 0;
 750 }
 751
 752 static int acpi_ec_add(struct acpi_device *device)
 753 {
 754         struct acpi_ec *ec = NULL;
 755
 756         if (!device)
 757                 return -EINVAL;
 758         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
 759         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
 760
 761         /* Check for boot EC */
 762         if (boot_ec) {
 763                 if (boot_ec->handle == device->handle) {
 764                         /* Pre-loaded EC from DSDT, just move pointer */
 765                         ec = boot_ec;
 766                         boot_ec = NULL;
 767                         goto end;
 768                 } else if (boot_ec->handle == ACPI_ROOT_OBJECT) {
 769                         /* ECDT-based EC, time to shut it down */
 770                         ec_remove_handlers(boot_ec);
 771                         kfree(boot_ec);
 772                         first_ec = boot_ec = NULL;
 773                 }
 774         }
 775
 776         ec = make_acpi_ec();
 777         if (!ec)
 778                 return -ENOMEM;
 779
 780         if (ec_parse_device(device->handle, 0, ec, NULL) !=
 781             AE_CTRL_TERMINATE) {
 782                 kfree(ec);
 783                 return -EINVAL;
 784         }
 785         ec->handle = device->handle;
 786       end:
 787         if (!first_ec)
 788                 first_ec = ec;
 789         acpi_driver_data(device) = ec;
 790         acpi_ec_add_fs(device);
 791         pr_info(PREFIX "GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n",
 792                           ec->gpe, ec->command_addr, ec->data_addr);
 793         pr_info(PREFIX "driver started in %s mode\n",
 794                 (test_bit(EC_FLAGS_GPE_MODE, &ec->flags))?"interrupt":"poll");
 795         return 0;
 796 }
 797
 798 static int acpi_ec_remove(struct acpi_device *device, int type)
 799 {
 800         struct acpi_ec *ec;
 801         struct acpi_ec_query_handler *handler, *tmp;
 802
 803         if (!device)
 804                 return -EINVAL;
 805
 806         ec = acpi_driver_data(device);
 807         mutex_lock(&ec->lock);
 808         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
 809                 list_del(&handler->node);
 810                 kfree(handler);
 811         }
 812         mutex_unlock(&ec->lock);
 813         acpi_ec_remove_fs(device);
 814         acpi_driver_data(device) = NULL;
 815         if (ec == first_ec)
 816                 first_ec = NULL;
 817         kfree(ec);
 818         return 0;
 819 }
 820
 821 static acpi_status
 822 ec_parse_io_ports(struct acpi_resource *resource, void *context)
 823 {
 824         struct acpi_ec *ec = context;
 825
 826         if (resource->type != ACPI_RESOURCE_TYPE_IO)
 827                 return AE_OK;
 828
 829         /*
 830          * The first address region returned is the data port, and
 831          * the second address region returned is the status/command
 832          * port.
 833          */
 834         if (ec->data_addr == 0)
 835                 ec->data_addr = resource->data.io.minimum;
 836         else if (ec->command_addr == 0)
 837                 ec->command_addr = resource->data.io.minimum;
 838         else
 839                 return AE_CTRL_TERMINATE;
 840
 841         return AE_OK;
 842 }
 843
 844 static int ec_install_handlers(struct acpi_ec *ec)
 845 {
 846         acpi_status status;
 847         if (ec->handlers_installed)
 848                 return 0;
 849         status = acpi_install_gpe_handler(NULL, ec->gpe,
 850                                           ACPI_GPE_EDGE_TRIGGERED,
 851                                           &acpi_ec_gpe_handler, ec);
 852         if (ACPI_FAILURE(status))
 853                 return -ENODEV;
 854
 855         acpi_set_gpe_type(NULL, ec->gpe, ACPI_GPE_TYPE_RUNTIME);
 856         acpi_enable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
 857
 858         status = acpi_install_address_space_handler(ec->handle,
 859                                                     ACPI_ADR_SPACE_EC,
 860                                                     &acpi_ec_space_handler,
 861                                                     &acpi_ec_space_setup, ec);
 862         if (ACPI_FAILURE(status)) {
 863                 acpi_remove_gpe_handler(NULL, ec->gpe, &acpi_ec_gpe_handler);
 864                 return -ENODEV;
 865         }
 866
 867         ec->handlers_installed = 1;
 868         return 0;
 869 }
 870
 871 static int acpi_ec_start(struct acpi_device *device)
 872 {
 873         struct acpi_ec *ec;
 874         int ret = 0;
 875
 876         if (!device)
 877                 return -EINVAL;
 878
 879         ec = acpi_driver_data(device);
 880
 881         if (!ec)
 882                 return -EINVAL;
 883
 884         ret = ec_install_handlers(ec);
 885
 886         /* EC is fully operational, allow queries */
 887         clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
 888         ec_schedule_ec_poll(ec);
 889         return ret;
 890 }
 891
 892 static int acpi_ec_stop(struct acpi_device *device, int type)
 893 {
 894         struct acpi_ec *ec;
 895         if (!device)
 896                 return -EINVAL;
 897         ec = acpi_driver_data(device);
 898         if (!ec)
 899                 return -EINVAL;
 900         ec_remove_handlers(ec);
 901
 902         return 0;
 903 }
 904
 905 int __init acpi_boot_ec_enable(void)
 906 {
 907         if (!boot_ec || boot_ec->handlers_installed)
 908                 return 0;
 909         if (!ec_install_handlers(boot_ec)) {
 910                 first_ec = boot_ec;
 911                 return 0;
 912         }
 913         return -EFAULT;
 914 }
 915
 916 static const struct acpi_device_id ec_device_ids[] = {
 917         {"PNP0C09", 0},
 918         {"", 0},
 919 };
 920
 921 int __init acpi_ec_ecdt_probe(void)
 922 {
 923         int ret;
 924         acpi_status status;
 925         struct acpi_table_ecdt *ecdt_ptr;
 926
 927         boot_ec = make_acpi_ec();
 928         if (!boot_ec)
 929                 return -ENOMEM;
 930         /*
 931          * Generate a boot ec context
 932          */
 933         status = acpi_get_table(ACPI_SIG_ECDT, 1,
 934                                 (struct acpi_table_header **)&ecdt_ptr);
 935         if (ACPI_SUCCESS(status)) {
 936                 pr_info(PREFIX "EC description table is found, configuring boot EC\n");
 937                 boot_ec->command_addr = ecdt_ptr->control.address;
 938                 boot_ec->data_addr = ecdt_ptr->data.address;
 939                 boot_ec->gpe = ecdt_ptr->gpe;
 940                 boot_ec->handle = ACPI_ROOT_OBJECT;
 941         } else {
 942                 /* This workaround is needed only on some broken machines,
 943                  * which require early EC, but fail to provide ECDT */
 944                 acpi_handle x;
 945                 printk(KERN_DEBUG PREFIX "Look up EC in DSDT\n");
 946                 status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device,
 947                                                 boot_ec, NULL);
 948                 /* Check that acpi_get_devices actually find something */
 949                 if (ACPI_FAILURE(status) || !boot_ec->handle)
 950                         goto error;
 951                 /* We really need to limit this workaround, the only ASUS,
 952                  * which needs it, has fake EC._INI method, so use it as flag.
 953                  * Keep boot_ec struct as it will be needed soon.
 954                  */
 955                 if (ACPI_FAILURE(acpi_get_handle(boot_ec->handle, "_INI", &x)))
 956                         return -ENODEV;
 957         }
 958
 959         ret = ec_install_handlers(boot_ec);
 960         if (!ret) {
 961                 first_ec = boot_ec;
 962                 return 0;
 963         }
 964       error:
 965         kfree(boot_ec);
 966         boot_ec = NULL;
 967         return -ENODEV;
 968 }
 969
 970 static int acpi_ec_suspend(struct acpi_device *device, pm_message_t state)
 971 {
 972         struct acpi_ec *ec = acpi_driver_data(device);
 973         /* Stop using GPE */
 974         set_bit(EC_FLAGS_NO_GPE, &ec->flags);
 975         clear_bit(EC_FLAGS_GPE_MODE, &ec->flags);
 976         acpi_disable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
 977         return 0;
 978 }
 979
 980 static int acpi_ec_resume(struct acpi_device *device)
 981 {
 982         struct acpi_ec *ec = acpi_driver_data(device);
 983         /* Enable use of GPE back */
 984         clear_bit(EC_FLAGS_NO_GPE, &ec->flags);
 985         acpi_enable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
 986         return 0;
 987 }
 988
 989 static struct acpi_driver acpi_ec_driver = {
 990         .name = "ec",
 991         .class = ACPI_EC_CLASS,
 992         .ids = ec_device_ids,
 993         .ops = {
 994                 .add = acpi_ec_add,
 995                 .remove = acpi_ec_remove,
 996                 .start = acpi_ec_start,
 997                 .stop = acpi_ec_stop,
 998                 .suspend = acpi_ec_suspend,
 999                 .resume = acpi_ec_resume,
1000                 },
1001 };
1002
1003 static int __init acpi_ec_init(void)
1004 {
1005         int result = 0;
1006
1007         if (acpi_disabled)
1008                 return 0;
1009
1010         acpi_ec_dir = proc_mkdir(ACPI_EC_CLASS, acpi_root_dir);
1011         if (!acpi_ec_dir)
1012                 return -ENODEV;
1013
1014         /* Now register the driver for the EC */
1015         result = acpi_bus_register_driver(&acpi_ec_driver);
1016         if (result < 0) {
1017                 remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1018                 return -ENODEV;
1019         }
1020
1021         return result;
1022 }
1023
1024 subsys_initcall(acpi_ec_init);
1025
1026 /* EC driver currently not unloadable */
1027 #if 0
1028 static void __exit acpi_ec_exit(void)
1029 {
1030
1031         acpi_bus_unregister_driver(&acpi_ec_driver);
1032
1033         remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1034
1035         return;
1036 }
1037 #endif  /* 0 */