SAFE public projects git trees. - safe/jmp/linux-2.6/blob - drivers/acpi/ec.c

   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 #include <linux/kernel.h>
  30 #include <linux/module.h>
  31 #include <linux/init.h>
  32 #include <linux/types.h>
  33 #include <linux/delay.h>
  34 #include <linux/proc_fs.h>
  35 #include <linux/seq_file.h>
  36 #include <linux/interrupt.h>
  37 #include <linux/list.h>
  38 #include <asm/io.h>
  39 #include <acpi/acpi_bus.h>
  40 #include <acpi/acpi_drivers.h>
  41 #include <acpi/actypes.h>
  42
  43 #define ACPI_EC_CLASS                   "embedded_controller"
  44 #define ACPI_EC_DEVICE_NAME             "Embedded Controller"
  45 #define ACPI_EC_FILE_INFO               "info"
  46
  47 #undef PREFIX
  48 #define PREFIX                          "ACPI: EC: "
  49
  50 /* Uncomment next line to get verbose print outs*/
  51 /* #define DEBUG */
  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
  77 enum {
  78         EC_FLAGS_WAIT_GPE = 0,          /* Don't check status until GPE arrives */
  79         EC_FLAGS_QUERY_PENDING,         /* Query is pending */
  80         EC_FLAGS_GPE_MODE,              /* Expect GPE to be sent for status change */
  81         EC_FLAGS_ONLY_IBF_GPE,          /* Expect GPE only for IBF = 0 event */
  82 };
  83
  84 static int acpi_ec_remove(struct acpi_device *device, int type);
  85 static int acpi_ec_start(struct acpi_device *device);
  86 static int acpi_ec_stop(struct acpi_device *device, int type);
  87 static int acpi_ec_add(struct acpi_device *device);
  88
  89 static const struct acpi_device_id ec_device_ids[] = {
  90         {"PNP0C09", 0},
  91         {"", 0},
  92 };
  93
  94 static struct acpi_driver acpi_ec_driver = {
  95         .name = "ec",
  96         .class = ACPI_EC_CLASS,
  97         .ids = ec_device_ids,
  98         .ops = {
  99                 .add = acpi_ec_add,
 100                 .remove = acpi_ec_remove,
 101                 .start = acpi_ec_start,
 102                 .stop = acpi_ec_stop,
 103                 },
 104 };
 105
 106 /* If we find an EC via the ECDT, we need to keep a ptr to its context */
 107 /* External interfaces use first EC only, so remember */
 108 typedef int (*acpi_ec_query_func) (void *data);
 109
 110 struct acpi_ec_query_handler {
 111         struct list_head node;
 112         acpi_ec_query_func func;
 113         acpi_handle handle;
 114         void *data;
 115         u8 query_bit;
 116 };
 117
 118 static struct acpi_ec {
 119         acpi_handle handle;
 120         unsigned long gpe;
 121         unsigned long command_addr;
 122         unsigned long data_addr;
 123         unsigned long global_lock;
 124         unsigned long flags;
 125         struct mutex lock;
 126         wait_queue_head_t wait;
 127         struct list_head list;
 128         u8 handlers_installed;
 129 } *boot_ec, *first_ec;
 130
 131 /* --------------------------------------------------------------------------
 132                              Transaction Management
 133    -------------------------------------------------------------------------- */
 134
 135 static inline u8 acpi_ec_read_status(struct acpi_ec *ec)
 136 {
 137         u8 x = inb(ec->command_addr);
 138         pr_debug(PREFIX "---> status = 0x%2x\n", x);
 139         return x;
 140 }
 141
 142 static inline u8 acpi_ec_read_data(struct acpi_ec *ec)
 143 {
 144         u8 x = inb(ec->data_addr);
 145         pr_debug(PREFIX "---> data = 0x%2x\n", x);
 146         return inb(ec->data_addr);
 147 }
 148
 149 static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command)
 150 {
 151         pr_debug(PREFIX "<--- command = 0x%2x\n", command);
 152         outb(command, ec->command_addr);
 153 }
 154
 155 static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data)
 156 {
 157         pr_debug(PREFIX "<--- data = 0x%2x\n", data);
 158         outb(data, ec->data_addr);
 159 }
 160
 161 static inline int acpi_ec_check_status(struct acpi_ec *ec, enum ec_event event)
 162 {
 163         if (test_bit(EC_FLAGS_WAIT_GPE, &ec->flags))
 164                 return 0;
 165         if (event == ACPI_EC_EVENT_OBF_1) {
 166                 if (acpi_ec_read_status(ec) & ACPI_EC_FLAG_OBF)
 167                         return 1;
 168         } else if (event == ACPI_EC_EVENT_IBF_0) {
 169                 if (!(acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF))
 170                         return 1;
 171         }
 172
 173         return 0;
 174 }
 175
 176 static int acpi_ec_wait(struct acpi_ec *ec, enum ec_event event, int force_poll)
 177 {
 178         if (likely(test_bit(EC_FLAGS_GPE_MODE, &ec->flags)) &&
 179             likely(!force_poll)) {
 180                 if (wait_event_timeout(ec->wait, acpi_ec_check_status(ec, event),
 181                                        msecs_to_jiffies(ACPI_EC_DELAY)))
 182                         return 0;
 183                 clear_bit(EC_FLAGS_WAIT_GPE, &ec->flags);
 184                 if (acpi_ec_check_status(ec, event)) {
 185                         if (event == ACPI_EC_EVENT_OBF_1) {
 186                                 /* miss OBF = 1 GPE, don't expect it anymore */
 187                                 pr_info(PREFIX "missing OBF_1 confirmation,"
 188                                         "switching to degraded mode.\n");
 189                                 set_bit(EC_FLAGS_ONLY_IBF_GPE, &ec->flags);
 190                         } else {
 191                                 /* missing GPEs, switch back to poll mode */
 192                                 if (printk_ratelimit())
 193                                         pr_info(PREFIX "missing IBF_1 confirmations,"
 194                                                 "switch off interrupt mode.\n");
 195                                 clear_bit(EC_FLAGS_GPE_MODE, &ec->flags);
 196                         }
 197                         return 0;
 198                 }
 199         } else {
 200                 unsigned long delay = jiffies + msecs_to_jiffies(ACPI_EC_DELAY);
 201                 clear_bit(EC_FLAGS_WAIT_GPE, &ec->flags);
 202                 while (time_before(jiffies, delay)) {
 203                         if (acpi_ec_check_status(ec, event))
 204                                 return 0;
 205                 }
 206         }
 207         pr_err(PREFIX "acpi_ec_wait timeout,"
 208                                " status = %d, expect_event = %d\n",
 209                                acpi_ec_read_status(ec), event);
 210         return -ETIME;
 211 }
 212
 213 static int acpi_ec_transaction_unlocked(struct acpi_ec *ec, u8 command,
 214                                         const u8 * wdata, unsigned wdata_len,
 215                                         u8 * rdata, unsigned rdata_len,
 216                                         int force_poll)
 217 {
 218         int result = 0;
 219         set_bit(EC_FLAGS_WAIT_GPE, &ec->flags);
 220         acpi_ec_write_cmd(ec, command);
 221         pr_debug(PREFIX "transaction start\n");
 222         for (; wdata_len > 0; --wdata_len) {
 223                 result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0, force_poll);
 224                 if (result) {
 225                         pr_err(PREFIX
 226                                "write_cmd timeout, command = %d\n", command);
 227                         goto end;
 228                 }
 229                 set_bit(EC_FLAGS_WAIT_GPE, &ec->flags);
 230                 acpi_ec_write_data(ec, *(wdata++));
 231         }
 232
 233         if (!rdata_len) {
 234                 result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0, force_poll);
 235                 if (result) {
 236                         pr_err(PREFIX
 237                                "finish-write timeout, command = %d\n", command);
 238                         goto end;
 239                 }
 240         } else if (command == ACPI_EC_COMMAND_QUERY)
 241                 clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
 242
 243         for (; rdata_len > 0; --rdata_len) {
 244                 if (test_bit(EC_FLAGS_ONLY_IBF_GPE, &ec->flags))
 245                         force_poll = 1;
 246                 result = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF_1, force_poll);
 247                 if (result) {
 248                         pr_err(PREFIX "read timeout, command = %d\n", command);
 249                         goto end;
 250                 }
 251                 /* Don't expect GPE after last read */
 252                 if (rdata_len > 1)
 253                         set_bit(EC_FLAGS_WAIT_GPE, &ec->flags);
 254                 *(rdata++) = acpi_ec_read_data(ec);
 255         }
 256       end:
 257         pr_debug(PREFIX "transaction end\n");
 258         return result;
 259 }
 260
 261 static int acpi_ec_transaction(struct acpi_ec *ec, u8 command,
 262                                const u8 * wdata, unsigned wdata_len,
 263                                u8 * rdata, unsigned rdata_len,
 264                                int force_poll)
 265 {
 266         int status;
 267         u32 glk;
 268
 269         if (!ec || (wdata_len && !wdata) || (rdata_len && !rdata))
 270                 return -EINVAL;
 271
 272         if (rdata)
 273                 memset(rdata, 0, rdata_len);
 274
 275         mutex_lock(&ec->lock);
 276         if (ec->global_lock) {
 277                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 278                 if (ACPI_FAILURE(status)) {
 279                         mutex_unlock(&ec->lock);
 280                         return -ENODEV;
 281                 }
 282         }
 283
 284         status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0, 0);
 285         if (status) {
 286                 pr_err(PREFIX "input buffer is not empty, "
 287                                 "aborting transaction\n");
 288                 goto end;
 289         }
 290
 291         status = acpi_ec_transaction_unlocked(ec, command,
 292                                               wdata, wdata_len,
 293                                               rdata, rdata_len,
 294                                               force_poll);
 295
 296       end:
 297
 298         if (ec->global_lock)
 299                 acpi_release_global_lock(glk);
 300         mutex_unlock(&ec->lock);
 301
 302         return status;
 303 }
 304
 305 /*
 306  * Note: samsung nv5000 doesn't work with ec burst mode.
 307  * http://bugzilla.kernel.org/show_bug.cgi?id=4980
 308  */
 309 int acpi_ec_burst_enable(struct acpi_ec *ec)
 310 {
 311         u8 d;
 312         return acpi_ec_transaction(ec, ACPI_EC_BURST_ENABLE, NULL, 0, &d, 1, 0);
 313 }
 314
 315 int acpi_ec_burst_disable(struct acpi_ec *ec)
 316 {
 317         return acpi_ec_transaction(ec, ACPI_EC_BURST_DISABLE, NULL, 0, NULL, 0, 0);
 318 }
 319
 320 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 * data)
 321 {
 322         int result;
 323         u8 d;
 324
 325         result = acpi_ec_transaction(ec, ACPI_EC_COMMAND_READ,
 326                                      &address, 1, &d, 1, 0);
 327         *data = d;
 328         return result;
 329 }
 330
 331 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
 332 {
 333         u8 wdata[2] = { address, data };
 334         return acpi_ec_transaction(ec, ACPI_EC_COMMAND_WRITE,
 335                                    wdata, 2, NULL, 0, 0);
 336 }
 337
 338 /*
 339  * Externally callable EC access functions. For now, assume 1 EC only
 340  */
 341 int ec_burst_enable(void)
 342 {
 343         if (!first_ec)
 344                 return -ENODEV;
 345         return acpi_ec_burst_enable(first_ec);
 346 }
 347
 348 EXPORT_SYMBOL(ec_burst_enable);
 349
 350 int ec_burst_disable(void)
 351 {
 352         if (!first_ec)
 353                 return -ENODEV;
 354         return acpi_ec_burst_disable(first_ec);
 355 }
 356
 357 EXPORT_SYMBOL(ec_burst_disable);
 358
 359 int ec_read(u8 addr, u8 * val)
 360 {
 361         int err;
 362         u8 temp_data;
 363
 364         if (!first_ec)
 365                 return -ENODEV;
 366
 367         err = acpi_ec_read(first_ec, addr, &temp_data);
 368
 369         if (!err) {
 370                 *val = temp_data;
 371                 return 0;
 372         } else
 373                 return err;
 374 }
 375
 376 EXPORT_SYMBOL(ec_read);
 377
 378 int ec_write(u8 addr, u8 val)
 379 {
 380         int err;
 381
 382         if (!first_ec)
 383                 return -ENODEV;
 384
 385         err = acpi_ec_write(first_ec, addr, val);
 386
 387         return err;
 388 }
 389
 390 EXPORT_SYMBOL(ec_write);
 391
 392 int ec_transaction(u8 command,
 393                    const u8 * wdata, unsigned wdata_len,
 394                    u8 * rdata, unsigned rdata_len,
 395                    int force_poll)
 396 {
 397         if (!first_ec)
 398                 return -ENODEV;
 399
 400         return acpi_ec_transaction(first_ec, command, wdata,
 401                                    wdata_len, rdata, rdata_len,
 402                                    force_poll);
 403 }
 404
 405 EXPORT_SYMBOL(ec_transaction);
 406
 407 static int acpi_ec_query(struct acpi_ec *ec, u8 * data)
 408 {
 409         int result;
 410         u8 d;
 411
 412         if (!ec || !data)
 413                 return -EINVAL;
 414
 415         /*
 416          * Query the EC to find out which _Qxx method we need to evaluate.
 417          * Note that successful completion of the query causes the ACPI_EC_SCI
 418          * bit to be cleared (and thus clearing the interrupt source).
 419          */
 420
 421         result = acpi_ec_transaction(ec, ACPI_EC_COMMAND_QUERY, NULL, 0, &d, 1, 0);
 422         if (result)
 423                 return result;
 424
 425         if (!d)
 426                 return -ENODATA;
 427
 428         *data = d;
 429         return 0;
 430 }
 431
 432 /* --------------------------------------------------------------------------
 433                                 Event Management
 434    -------------------------------------------------------------------------- */
 435 int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
 436                               acpi_handle handle, acpi_ec_query_func func,
 437                               void *data)
 438 {
 439         struct acpi_ec_query_handler *handler =
 440             kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL);
 441         if (!handler)
 442                 return -ENOMEM;
 443
 444         handler->query_bit = query_bit;
 445         handler->handle = handle;
 446         handler->func = func;
 447         handler->data = data;
 448         mutex_lock(&ec->lock);
 449         list_add(&handler->node, &ec->list);
 450         mutex_unlock(&ec->lock);
 451         return 0;
 452 }
 453
 454 EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler);
 455
 456 void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit)
 457 {
 458         struct acpi_ec_query_handler *handler, *tmp;
 459         mutex_lock(&ec->lock);
 460         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
 461                 if (query_bit == handler->query_bit) {
 462                         list_del(&handler->node);
 463                         kfree(handler);
 464                 }
 465         }
 466         mutex_unlock(&ec->lock);
 467 }
 468
 469 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler);
 470
 471 static void acpi_ec_gpe_query(void *ec_cxt)
 472 {
 473         struct acpi_ec *ec = ec_cxt;
 474         u8 value = 0;
 475         struct acpi_ec_query_handler *handler, copy;
 476
 477         if (!ec || acpi_ec_query(ec, &value))
 478                 return;
 479         mutex_lock(&ec->lock);
 480         list_for_each_entry(handler, &ec->list, node) {
 481                 if (value == handler->query_bit) {
 482                         /* have custom handler for this bit */
 483                         memcpy(&copy, handler, sizeof(copy));
 484                         mutex_unlock(&ec->lock);
 485                         if (copy.func) {
 486                                 copy.func(copy.data);
 487                         } else if (copy.handle) {
 488                                 acpi_evaluate_object(copy.handle, NULL, NULL, NULL);
 489                         }
 490                         return;
 491                 }
 492         }
 493         mutex_unlock(&ec->lock);
 494 }
 495
 496 static u32 acpi_ec_gpe_handler(void *data)
 497 {
 498         acpi_status status = AE_OK;
 499         struct acpi_ec *ec = data;
 500
 501         pr_debug(PREFIX "~~~> interrupt\n");
 502         clear_bit(EC_FLAGS_WAIT_GPE, &ec->flags);
 503         if (test_bit(EC_FLAGS_GPE_MODE, &ec->flags))
 504                 wake_up(&ec->wait);
 505
 506         if (acpi_ec_read_status(ec) & ACPI_EC_FLAG_SCI) {
 507                 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags))
 508                         status = acpi_os_execute(OSL_EC_BURST_HANDLER,
 509                                 acpi_ec_gpe_query, ec);
 510         } else if (unlikely(!test_bit(EC_FLAGS_GPE_MODE, &ec->flags))) {
 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         }
 517
 518         return ACPI_SUCCESS(status) ?
 519             ACPI_INTERRUPT_HANDLED : ACPI_INTERRUPT_NOT_HANDLED;
 520 }
 521
 522 /* --------------------------------------------------------------------------
 523                              Address Space Management
 524    -------------------------------------------------------------------------- */
 525
 526 static acpi_status
 527 acpi_ec_space_setup(acpi_handle region_handle,
 528                     u32 function, void *handler_context, void **return_context)
 529 {
 530         /*
 531          * The EC object is in the handler context and is needed
 532          * when calling the acpi_ec_space_handler.
 533          */
 534         *return_context = (function != ACPI_REGION_DEACTIVATE) ?
 535             handler_context : NULL;
 536
 537         return AE_OK;
 538 }
 539
 540 static acpi_status
 541 acpi_ec_space_handler(u32 function, acpi_physical_address address,
 542                       u32 bits, acpi_integer *value,
 543                       void *handler_context, void *region_context)
 544 {
 545         struct acpi_ec *ec = handler_context;
 546         int result = 0, i = 0;
 547         u8 temp = 0;
 548
 549         if ((address > 0xFF) || !value || !handler_context)
 550                 return AE_BAD_PARAMETER;
 551
 552         if (function != ACPI_READ && function != ACPI_WRITE)
 553                 return AE_BAD_PARAMETER;
 554
 555         if (bits != 8 && acpi_strict)
 556                 return AE_BAD_PARAMETER;
 557
 558         while (bits - i > 0) {
 559                 if (function == ACPI_READ) {
 560                         result = acpi_ec_read(ec, address, &temp);
 561                         (*value) |= ((acpi_integer)temp) << i;
 562                 } else {
 563                         temp = 0xff & ((*value) >> i);
 564                         result = acpi_ec_write(ec, address, temp);
 565                 }
 566                 i += 8;
 567                 ++address;
 568         }
 569
 570         switch (result) {
 571         case -EINVAL:
 572                 return AE_BAD_PARAMETER;
 573                 break;
 574         case -ENODEV:
 575                 return AE_NOT_FOUND;
 576                 break;
 577         case -ETIME:
 578                 return AE_TIME;
 579                 break;
 580         default:
 581                 return AE_OK;
 582         }
 583 }
 584
 585 /* --------------------------------------------------------------------------
 586                               FS Interface (/proc)
 587    -------------------------------------------------------------------------- */
 588
 589 static struct proc_dir_entry *acpi_ec_dir;
 590
 591 static int acpi_ec_read_info(struct seq_file *seq, void *offset)
 592 {
 593         struct acpi_ec *ec = seq->private;
 594
 595         if (!ec)
 596                 goto end;
 597
 598         seq_printf(seq, "gpe:\t\t\t0x%02x\n", (u32) ec->gpe);
 599         seq_printf(seq, "ports:\t\t\t0x%02x, 0x%02x\n",
 600                    (unsigned)ec->command_addr, (unsigned)ec->data_addr);
 601         seq_printf(seq, "use global lock:\t%s\n",
 602                    ec->global_lock ? "yes" : "no");
 603       end:
 604         return 0;
 605 }
 606
 607 static int acpi_ec_info_open_fs(struct inode *inode, struct file *file)
 608 {
 609         return single_open(file, acpi_ec_read_info, PDE(inode)->data);
 610 }
 611
 612 static struct file_operations acpi_ec_info_ops = {
 613         .open = acpi_ec_info_open_fs,
 614         .read = seq_read,
 615         .llseek = seq_lseek,
 616         .release = single_release,
 617         .owner = THIS_MODULE,
 618 };
 619
 620 static int acpi_ec_add_fs(struct acpi_device *device)
 621 {
 622         struct proc_dir_entry *entry = NULL;
 623
 624         if (!acpi_device_dir(device)) {
 625                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
 626                                                      acpi_ec_dir);
 627                 if (!acpi_device_dir(device))
 628                         return -ENODEV;
 629         }
 630
 631         entry = create_proc_entry(ACPI_EC_FILE_INFO, S_IRUGO,
 632                                   acpi_device_dir(device));
 633         if (!entry)
 634                 return -ENODEV;
 635         else {
 636                 entry->proc_fops = &acpi_ec_info_ops;
 637                 entry->data = acpi_driver_data(device);
 638                 entry->owner = THIS_MODULE;
 639         }
 640
 641         return 0;
 642 }
 643
 644 static int acpi_ec_remove_fs(struct acpi_device *device)
 645 {
 646
 647         if (acpi_device_dir(device)) {
 648                 remove_proc_entry(ACPI_EC_FILE_INFO, acpi_device_dir(device));
 649                 remove_proc_entry(acpi_device_bid(device), acpi_ec_dir);
 650                 acpi_device_dir(device) = NULL;
 651         }
 652
 653         return 0;
 654 }
 655
 656 /* --------------------------------------------------------------------------
 657                                Driver Interface
 658    -------------------------------------------------------------------------- */
 659 static acpi_status
 660 ec_parse_io_ports(struct acpi_resource *resource, void *context);
 661
 662 static struct acpi_ec *make_acpi_ec(void)
 663 {
 664         struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
 665         if (!ec)
 666                 return NULL;
 667         ec->flags = 1 << EC_FLAGS_QUERY_PENDING;
 668         mutex_init(&ec->lock);
 669         init_waitqueue_head(&ec->wait);
 670         INIT_LIST_HEAD(&ec->list);
 671         return ec;
 672 }
 673
 674 static acpi_status
 675 acpi_ec_register_query_methods(acpi_handle handle, u32 level,
 676                                void *context, void **return_value)
 677 {
 678         struct acpi_namespace_node *node = handle;
 679         struct acpi_ec *ec = context;
 680         int value = 0;
 681         if (sscanf(node->name.ascii, "_Q%x", &value) == 1) {
 682                 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL);
 683         }
 684         return AE_OK;
 685 }
 686
 687 static acpi_status
 688 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
 689 {
 690         acpi_status status;
 691
 692         struct acpi_ec *ec = context;
 693         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
 694                                      ec_parse_io_ports, ec);
 695         if (ACPI_FAILURE(status))
 696                 return status;
 697
 698         /* Get GPE bit assignment (EC events). */
 699         /* TODO: Add support for _GPE returning a package */
 700         status = acpi_evaluate_integer(handle, "_GPE", NULL, &ec->gpe);
 701         if (ACPI_FAILURE(status))
 702                 return status;
 703         /* Find and register all query methods */
 704         acpi_walk_namespace(ACPI_TYPE_METHOD, handle, 1,
 705                             acpi_ec_register_query_methods, ec, NULL);
 706         /* Use the global lock for all EC transactions? */
 707         acpi_evaluate_integer(handle, "_GLK", NULL, &ec->global_lock);
 708         ec->handle = handle;
 709         return AE_CTRL_TERMINATE;
 710 }
 711
 712 static void ec_remove_handlers(struct acpi_ec *ec)
 713 {
 714         if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle,
 715                                 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler)))
 716                 pr_err(PREFIX "failed to remove space handler\n");
 717         if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe,
 718                                 &acpi_ec_gpe_handler)))
 719                 pr_err(PREFIX "failed to remove gpe handler\n");
 720         ec->handlers_installed = 0;
 721 }
 722
 723 static int acpi_ec_add(struct acpi_device *device)
 724 {
 725         struct acpi_ec *ec = NULL;
 726
 727         if (!device)
 728                 return -EINVAL;
 729         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
 730         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
 731
 732         /* Check for boot EC */
 733         if (boot_ec) {
 734                 if (boot_ec->handle == device->handle) {
 735                         /* Pre-loaded EC from DSDT, just move pointer */
 736                         ec = boot_ec;
 737                         boot_ec = NULL;
 738                         goto end;
 739                 } else if (boot_ec->handle == ACPI_ROOT_OBJECT) {
 740                         /* ECDT-based EC, time to shut it down */
 741                         ec_remove_handlers(boot_ec);
 742                         kfree(boot_ec);
 743                         first_ec = boot_ec = NULL;
 744                 }
 745         }
 746
 747         ec = make_acpi_ec();
 748         if (!ec)
 749                 return -ENOMEM;
 750
 751         if (ec_parse_device(device->handle, 0, ec, NULL) !=
 752             AE_CTRL_TERMINATE) {
 753                 kfree(ec);
 754                 return -EINVAL;
 755         }
 756         ec->handle = device->handle;
 757       end:
 758         if (!first_ec)
 759                 first_ec = ec;
 760         acpi_driver_data(device) = ec;
 761         acpi_ec_add_fs(device);
 762         pr_info(PREFIX "GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n",
 763                           ec->gpe, ec->command_addr, ec->data_addr);
 764         pr_info(PREFIX "driver started in %s mode\n",
 765                 (test_bit(EC_FLAGS_GPE_MODE, &ec->flags))?"interrupt":"poll");
 766         return 0;
 767 }
 768
 769 static int acpi_ec_remove(struct acpi_device *device, int type)
 770 {
 771         struct acpi_ec *ec;
 772         struct acpi_ec_query_handler *handler, *tmp;
 773
 774         if (!device)
 775                 return -EINVAL;
 776
 777         ec = acpi_driver_data(device);
 778         mutex_lock(&ec->lock);
 779         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
 780                 list_del(&handler->node);
 781                 kfree(handler);
 782         }
 783         mutex_unlock(&ec->lock);
 784         acpi_ec_remove_fs(device);
 785         acpi_driver_data(device) = NULL;
 786         if (ec == first_ec)
 787                 first_ec = NULL;
 788         kfree(ec);
 789         return 0;
 790 }
 791
 792 static acpi_status
 793 ec_parse_io_ports(struct acpi_resource *resource, void *context)
 794 {
 795         struct acpi_ec *ec = context;
 796
 797         if (resource->type != ACPI_RESOURCE_TYPE_IO)
 798                 return AE_OK;
 799
 800         /*
 801          * The first address region returned is the data port, and
 802          * the second address region returned is the status/command
 803          * port.
 804          */
 805         if (ec->data_addr == 0)
 806                 ec->data_addr = resource->data.io.minimum;
 807         else if (ec->command_addr == 0)
 808                 ec->command_addr = resource->data.io.minimum;
 809         else
 810                 return AE_CTRL_TERMINATE;
 811
 812         return AE_OK;
 813 }
 814
 815 static int ec_install_handlers(struct acpi_ec *ec)
 816 {
 817         acpi_status status;
 818         if (ec->handlers_installed)
 819                 return 0;
 820         status = acpi_install_gpe_handler(NULL, ec->gpe,
 821                                           ACPI_GPE_EDGE_TRIGGERED,
 822                                           &acpi_ec_gpe_handler, ec);
 823         if (ACPI_FAILURE(status))
 824                 return -ENODEV;
 825
 826         acpi_set_gpe_type(NULL, ec->gpe, ACPI_GPE_TYPE_RUNTIME);
 827         acpi_enable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
 828
 829         status = acpi_install_address_space_handler(ec->handle,
 830                                                     ACPI_ADR_SPACE_EC,
 831                                                     &acpi_ec_space_handler,
 832                                                     &acpi_ec_space_setup, ec);
 833         if (ACPI_FAILURE(status)) {
 834                 acpi_remove_gpe_handler(NULL, ec->gpe, &acpi_ec_gpe_handler);
 835                 return -ENODEV;
 836         }
 837
 838         ec->handlers_installed = 1;
 839         return 0;
 840 }
 841
 842 static int acpi_ec_start(struct acpi_device *device)
 843 {
 844         struct acpi_ec *ec;
 845         int ret = 0;
 846
 847         if (!device)
 848                 return -EINVAL;
 849
 850         ec = acpi_driver_data(device);
 851
 852         if (!ec)
 853                 return -EINVAL;
 854
 855         ret = ec_install_handlers(ec);
 856
 857         /* EC is fully operational, allow queries */
 858         clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
 859         return ret;
 860 }
 861
 862 static int acpi_ec_stop(struct acpi_device *device, int type)
 863 {
 864         struct acpi_ec *ec;
 865         if (!device)
 866                 return -EINVAL;
 867         ec = acpi_driver_data(device);
 868         if (!ec)
 869                 return -EINVAL;
 870         ec_remove_handlers(ec);
 871
 872         return 0;
 873 }
 874
 875 int __init acpi_ec_ecdt_probe(void)
 876 {
 877         int ret;
 878         acpi_status status;
 879         struct acpi_table_ecdt *ecdt_ptr;
 880
 881         boot_ec = make_acpi_ec();
 882         if (!boot_ec)
 883                 return -ENOMEM;
 884         /*
 885          * Generate a boot ec context
 886          */
 887         status = acpi_get_table(ACPI_SIG_ECDT, 1,
 888                                 (struct acpi_table_header **)&ecdt_ptr);
 889         if (ACPI_SUCCESS(status)) {
 890                 pr_info(PREFIX "EC description table is found, configuring boot EC\n");
 891                 boot_ec->command_addr = ecdt_ptr->control.address;
 892                 boot_ec->data_addr = ecdt_ptr->data.address;
 893                 boot_ec->gpe = ecdt_ptr->gpe;
 894                 boot_ec->handle = ACPI_ROOT_OBJECT;
 895         } else {
 896                 printk(KERN_DEBUG PREFIX "Look up EC in DSDT\n");
 897                 status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device,
 898                                                 boot_ec, NULL);
 899                 /* Check that acpi_get_devices actually find something */
 900                 if (ACPI_FAILURE(status) || !boot_ec->handle)
 901                         goto error;
 902         }
 903
 904         ret = ec_install_handlers(boot_ec);
 905         if (!ret) {
 906                 first_ec = boot_ec;
 907                 return 0;
 908         }
 909       error:
 910         kfree(boot_ec);
 911         boot_ec = NULL;
 912         return -ENODEV;
 913 }
 914
 915 static int __init acpi_ec_init(void)
 916 {
 917         int result = 0;
 918
 919         if (acpi_disabled)
 920                 return 0;
 921
 922         acpi_ec_dir = proc_mkdir(ACPI_EC_CLASS, acpi_root_dir);
 923         if (!acpi_ec_dir)
 924                 return -ENODEV;
 925
 926         /* Now register the driver for the EC */
 927         result = acpi_bus_register_driver(&acpi_ec_driver);
 928         if (result < 0) {
 929                 remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
 930                 return -ENODEV;
 931         }
 932
 933         return result;
 934 }
 935
 936 subsys_initcall(acpi_ec_init);
 937
 938 /* EC driver currently not unloadable */
 939 #if 0
 940 static void __exit acpi_ec_exit(void)
 941 {
 942
 943         acpi_bus_unregister_driver(&acpi_ec_driver);
 944
 945         remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
 946
 947         return;
 948 }
 949 #endif  /* 0 */