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 /* EC status register */
  51 #define ACPI_EC_FLAG_OBF        0x01    /* Output buffer full */
  52 #define ACPI_EC_FLAG_IBF        0x02    /* Input buffer full */
  53 #define ACPI_EC_FLAG_BURST      0x10    /* burst mode */
  54 #define ACPI_EC_FLAG_SCI        0x20    /* EC-SCI occurred */
  55
  56 /* EC commands */
  57 enum ec_command {
  58         ACPI_EC_COMMAND_READ = 0x80,
  59         ACPI_EC_COMMAND_WRITE = 0x81,
  60         ACPI_EC_BURST_ENABLE = 0x82,
  61         ACPI_EC_BURST_DISABLE = 0x83,
  62         ACPI_EC_COMMAND_QUERY = 0x84,
  63 };
  64
  65 /* EC events */
  66 enum ec_event {
  67         ACPI_EC_EVENT_OBF_1 = 1,        /* Output buffer full */
  68         ACPI_EC_EVENT_IBF_0,            /* Input buffer empty */
  69 };
  70
  71 #define ACPI_EC_DELAY           500     /* Wait 500ms max. during EC ops */
  72 #define ACPI_EC_UDELAY_GLK      1000    /* Wait 1ms max. to get global lock */
  73
  74 enum {
  75         EC_FLAGS_WAIT_GPE = 0,          /* Don't check status until GPE arrives */
  76         EC_FLAGS_QUERY_PENDING,         /* Query is pending */
  77         EC_FLAGS_GPE_MODE,              /* Expect GPE to be sent for status change */
  78 };
  79
  80 static int acpi_ec_remove(struct acpi_device *device, int type);
  81 static int acpi_ec_start(struct acpi_device *device);
  82 static int acpi_ec_stop(struct acpi_device *device, int type);
  83 static int acpi_ec_add(struct acpi_device *device);
  84
  85 static const struct acpi_device_id ec_device_ids[] = {
  86         {"PNP0C09", 0},
  87         {"", 0},
  88 };
  89
  90 static struct acpi_driver acpi_ec_driver = {
  91         .name = "ec",
  92         .class = ACPI_EC_CLASS,
  93         .ids = ec_device_ids,
  94         .ops = {
  95                 .add = acpi_ec_add,
  96                 .remove = acpi_ec_remove,
  97                 .start = acpi_ec_start,
  98                 .stop = acpi_ec_stop,
  99                 },
 100 };
 101
 102 /* If we find an EC via the ECDT, we need to keep a ptr to its context */
 103 /* External interfaces use first EC only, so remember */
 104 typedef int (*acpi_ec_query_func) (void *data);
 105
 106 struct acpi_ec_query_handler {
 107         struct list_head node;
 108         acpi_ec_query_func func;
 109         acpi_handle handle;
 110         void *data;
 111         u8 query_bit;
 112 };
 113
 114 static struct acpi_ec {
 115         acpi_handle handle;
 116         unsigned long gpe;
 117         unsigned long command_addr;
 118         unsigned long data_addr;
 119         unsigned long global_lock;
 120         unsigned long flags;
 121         struct mutex lock;
 122         wait_queue_head_t wait;
 123         struct list_head list;
 124         u8 handlers_installed;
 125 } *boot_ec, *first_ec;
 126
 127 /* --------------------------------------------------------------------------
 128                              Transaction Management
 129    -------------------------------------------------------------------------- */
 130
 131 static inline u8 acpi_ec_read_status(struct acpi_ec *ec)
 132 {
 133         return inb(ec->command_addr);
 134 }
 135
 136 static inline u8 acpi_ec_read_data(struct acpi_ec *ec)
 137 {
 138         return inb(ec->data_addr);
 139 }
 140
 141 static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command)
 142 {
 143         outb(command, ec->command_addr);
 144 }
 145
 146 static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data)
 147 {
 148         outb(data, ec->data_addr);
 149 }
 150
 151 static inline int acpi_ec_check_status(struct acpi_ec *ec, enum ec_event event)
 152 {
 153         if (test_bit(EC_FLAGS_WAIT_GPE, &ec->flags))
 154                 return 0;
 155         if (event == ACPI_EC_EVENT_OBF_1) {
 156                 if (acpi_ec_read_status(ec) & ACPI_EC_FLAG_OBF)
 157                         return 1;
 158         } else if (event == ACPI_EC_EVENT_IBF_0) {
 159                 if (!(acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF))
 160                         return 1;
 161         }
 162
 163         return 0;
 164 }
 165
 166 static int acpi_ec_wait(struct acpi_ec *ec, enum ec_event event, int force_poll)
 167 {
 168         if (likely(test_bit(EC_FLAGS_GPE_MODE, &ec->flags)) &&
 169             likely(!force_poll)) {
 170                 if (wait_event_timeout(ec->wait, acpi_ec_check_status(ec, event),
 171                                        msecs_to_jiffies(ACPI_EC_DELAY)))
 172                         return 0;
 173                 clear_bit(EC_FLAGS_WAIT_GPE, &ec->flags);
 174                 if (acpi_ec_check_status(ec, event)) {
 175                         clear_bit(EC_FLAGS_GPE_MODE, &ec->flags);
 176                         return 0;
 177                 }
 178         } else {
 179                 unsigned long delay = jiffies + msecs_to_jiffies(ACPI_EC_DELAY);
 180                 clear_bit(EC_FLAGS_WAIT_GPE, &ec->flags);
 181                 while (time_before(jiffies, delay)) {
 182                         if (acpi_ec_check_status(ec, event))
 183                                 return 0;
 184                 }
 185         }
 186         printk(KERN_ERR PREFIX "acpi_ec_wait timeout,"
 187                                " status = %d, expect_event = %d\n",
 188                                acpi_ec_read_status(ec), event);
 189         return -ETIME;
 190 }
 191
 192 static int acpi_ec_transaction_unlocked(struct acpi_ec *ec, u8 command,
 193                                         const u8 * wdata, unsigned wdata_len,
 194                                         u8 * rdata, unsigned rdata_len,
 195                                         int force_poll)
 196 {
 197         int result = 0;
 198         set_bit(EC_FLAGS_WAIT_GPE, &ec->flags);
 199         acpi_ec_write_cmd(ec, command);
 200
 201         for (; wdata_len > 0; --wdata_len) {
 202                 result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0, force_poll);
 203                 if (result) {
 204                         printk(KERN_ERR PREFIX
 205                                "write_cmd timeout, command = %d\n", command);
 206                         goto end;
 207                 }
 208                 set_bit(EC_FLAGS_WAIT_GPE, &ec->flags);
 209                 acpi_ec_write_data(ec, *(wdata++));
 210         }
 211
 212         if (!rdata_len) {
 213                 result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0, force_poll);
 214                 if (result) {
 215                         printk(KERN_ERR PREFIX
 216                                "finish-write timeout, command = %d\n", command);
 217                         goto end;
 218                 }
 219         } else if (command == ACPI_EC_COMMAND_QUERY)
 220                 clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
 221
 222         for (; rdata_len > 0; --rdata_len) {
 223                 result = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF_1, force_poll);
 224                 if (result) {
 225                         printk(KERN_ERR PREFIX "read timeout, command = %d\n",
 226                                command);
 227                         goto end;
 228                 }
 229                 /* Don't expect GPE after last read */
 230                 if (rdata_len > 1)
 231                         set_bit(EC_FLAGS_WAIT_GPE, &ec->flags);
 232                 *(rdata++) = acpi_ec_read_data(ec);
 233         }
 234       end:
 235         return result;
 236 }
 237
 238 static int acpi_ec_transaction(struct acpi_ec *ec, u8 command,
 239                                const u8 * wdata, unsigned wdata_len,
 240                                u8 * rdata, unsigned rdata_len,
 241                                int force_poll)
 242 {
 243         int status;
 244         u32 glk;
 245
 246         if (!ec || (wdata_len && !wdata) || (rdata_len && !rdata))
 247                 return -EINVAL;
 248
 249         if (rdata)
 250                 memset(rdata, 0, rdata_len);
 251
 252         mutex_lock(&ec->lock);
 253         if (ec->global_lock) {
 254                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 255                 if (ACPI_FAILURE(status)) {
 256                         mutex_unlock(&ec->lock);
 257                         return -ENODEV;
 258                 }
 259         }
 260
 261         status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0, 0);
 262         if (status) {
 263                 printk(KERN_ERR PREFIX
 264                        "input buffer is not empty, aborting transaction\n");
 265                 goto end;
 266         }
 267
 268         status = acpi_ec_transaction_unlocked(ec, command,
 269                                               wdata, wdata_len,
 270                                               rdata, rdata_len,
 271                                               force_poll);
 272
 273       end:
 274
 275         if (ec->global_lock)
 276                 acpi_release_global_lock(glk);
 277         mutex_unlock(&ec->lock);
 278
 279         return status;
 280 }
 281
 282 /*
 283  * Note: samsung nv5000 doesn't work with ec burst mode.
 284  * http://bugzilla.kernel.org/show_bug.cgi?id=4980
 285  */
 286 int acpi_ec_burst_enable(struct acpi_ec *ec)
 287 {
 288         u8 d;
 289         return acpi_ec_transaction(ec, ACPI_EC_BURST_ENABLE, NULL, 0, &d, 1, 0);
 290 }
 291
 292 int acpi_ec_burst_disable(struct acpi_ec *ec)
 293 {
 294         return acpi_ec_transaction(ec, ACPI_EC_BURST_DISABLE, NULL, 0, NULL, 0, 0);
 295 }
 296
 297 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 * data)
 298 {
 299         int result;
 300         u8 d;
 301
 302         result = acpi_ec_transaction(ec, ACPI_EC_COMMAND_READ,
 303                                      &address, 1, &d, 1, 0);
 304         *data = d;
 305         return result;
 306 }
 307
 308 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
 309 {
 310         u8 wdata[2] = { address, data };
 311         return acpi_ec_transaction(ec, ACPI_EC_COMMAND_WRITE,
 312                                    wdata, 2, NULL, 0, 0);
 313 }
 314
 315 /*
 316  * Externally callable EC access functions. For now, assume 1 EC only
 317  */
 318 int ec_burst_enable(void)
 319 {
 320         if (!first_ec)
 321                 return -ENODEV;
 322         return acpi_ec_burst_enable(first_ec);
 323 }
 324
 325 EXPORT_SYMBOL(ec_burst_enable);
 326
 327 int ec_burst_disable(void)
 328 {
 329         if (!first_ec)
 330                 return -ENODEV;
 331         return acpi_ec_burst_disable(first_ec);
 332 }
 333
 334 EXPORT_SYMBOL(ec_burst_disable);
 335
 336 int ec_read(u8 addr, u8 * val)
 337 {
 338         int err;
 339         u8 temp_data;
 340
 341         if (!first_ec)
 342                 return -ENODEV;
 343
 344         err = acpi_ec_read(first_ec, addr, &temp_data);
 345
 346         if (!err) {
 347                 *val = temp_data;
 348                 return 0;
 349         } else
 350                 return err;
 351 }
 352
 353 EXPORT_SYMBOL(ec_read);
 354
 355 int ec_write(u8 addr, u8 val)
 356 {
 357         int err;
 358
 359         if (!first_ec)
 360                 return -ENODEV;
 361
 362         err = acpi_ec_write(first_ec, addr, val);
 363
 364         return err;
 365 }
 366
 367 EXPORT_SYMBOL(ec_write);
 368
 369 int ec_transaction(u8 command,
 370                    const u8 * wdata, unsigned wdata_len,
 371                    u8 * rdata, unsigned rdata_len,
 372                    int force_poll)
 373 {
 374         if (!first_ec)
 375                 return -ENODEV;
 376
 377         return acpi_ec_transaction(first_ec, command, wdata,
 378                                    wdata_len, rdata, rdata_len,
 379                                    force_poll);
 380 }
 381
 382 EXPORT_SYMBOL(ec_transaction);
 383
 384 static int acpi_ec_query(struct acpi_ec *ec, u8 * data)
 385 {
 386         int result;
 387         u8 d;
 388
 389         if (!ec || !data)
 390                 return -EINVAL;
 391
 392         /*
 393          * Query the EC to find out which _Qxx method we need to evaluate.
 394          * Note that successful completion of the query causes the ACPI_EC_SCI
 395          * bit to be cleared (and thus clearing the interrupt source).
 396          */
 397
 398         result = acpi_ec_transaction(ec, ACPI_EC_COMMAND_QUERY, NULL, 0, &d, 1, 0);
 399         if (result)
 400                 return result;
 401
 402         if (!d)
 403                 return -ENODATA;
 404
 405         *data = d;
 406         return 0;
 407 }
 408
 409 /* --------------------------------------------------------------------------
 410                                 Event Management
 411    -------------------------------------------------------------------------- */
 412 int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
 413                               acpi_handle handle, acpi_ec_query_func func,
 414                               void *data)
 415 {
 416         struct acpi_ec_query_handler *handler =
 417             kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL);
 418         if (!handler)
 419                 return -ENOMEM;
 420
 421         handler->query_bit = query_bit;
 422         handler->handle = handle;
 423         handler->func = func;
 424         handler->data = data;
 425         mutex_lock(&ec->lock);
 426         list_add(&handler->node, &ec->list);
 427         mutex_unlock(&ec->lock);
 428         return 0;
 429 }
 430
 431 EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler);
 432
 433 void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit)
 434 {
 435         struct acpi_ec_query_handler *handler;
 436         mutex_lock(&ec->lock);
 437         list_for_each_entry(handler, &ec->list, node) {
 438                 if (query_bit == handler->query_bit) {
 439                         list_del(&handler->node);
 440                         kfree(handler);
 441                 }
 442         }
 443         mutex_unlock(&ec->lock);
 444 }
 445
 446 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler);
 447
 448 static void acpi_ec_gpe_query(void *ec_cxt)
 449 {
 450         struct acpi_ec *ec = ec_cxt;
 451         u8 value = 0;
 452         struct acpi_ec_query_handler *handler, copy;
 453
 454         if (!ec || acpi_ec_query(ec, &value))
 455                 return;
 456         mutex_lock(&ec->lock);
 457         list_for_each_entry(handler, &ec->list, node) {
 458                 if (value == handler->query_bit) {
 459                         /* have custom handler for this bit */
 460                         memcpy(&copy, handler, sizeof(copy));
 461                         mutex_unlock(&ec->lock);
 462                         if (copy.func) {
 463                                 copy.func(copy.data);
 464                         } else if (copy.handle) {
 465                                 acpi_evaluate_object(copy.handle, NULL, NULL, NULL);
 466                         }
 467                         return;
 468                 }
 469         }
 470         mutex_unlock(&ec->lock);
 471 }
 472
 473 static u32 acpi_ec_gpe_handler(void *data)
 474 {
 475         acpi_status status = AE_OK;
 476         struct acpi_ec *ec = data;
 477
 478         clear_bit(EC_FLAGS_WAIT_GPE, &ec->flags);
 479         if (test_bit(EC_FLAGS_GPE_MODE, &ec->flags))
 480                 wake_up(&ec->wait);
 481
 482         if (acpi_ec_read_status(ec) & ACPI_EC_FLAG_SCI) {
 483                 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags))
 484                         status = acpi_os_execute(OSL_EC_BURST_HANDLER,
 485                                 acpi_ec_gpe_query, ec);
 486         } else if (unlikely(!test_bit(EC_FLAGS_GPE_MODE, &ec->flags)))
 487                 set_bit(EC_FLAGS_GPE_MODE, &ec->flags);
 488
 489         return ACPI_SUCCESS(status) ?
 490             ACPI_INTERRUPT_HANDLED : ACPI_INTERRUPT_NOT_HANDLED;
 491 }
 492
 493 /* --------------------------------------------------------------------------
 494                              Address Space Management
 495    -------------------------------------------------------------------------- */
 496
 497 static acpi_status
 498 acpi_ec_space_setup(acpi_handle region_handle,
 499                     u32 function, void *handler_context, void **return_context)
 500 {
 501         /*
 502          * The EC object is in the handler context and is needed
 503          * when calling the acpi_ec_space_handler.
 504          */
 505         *return_context = (function != ACPI_REGION_DEACTIVATE) ?
 506             handler_context : NULL;
 507
 508         return AE_OK;
 509 }
 510
 511 static acpi_status
 512 acpi_ec_space_handler(u32 function, acpi_physical_address address,
 513                       u32 bits, acpi_integer *value,
 514                       void *handler_context, void *region_context)
 515 {
 516         struct acpi_ec *ec = handler_context;
 517         int result = 0, i = 0;
 518         u8 temp = 0;
 519
 520         if ((address > 0xFF) || !value || !handler_context)
 521                 return AE_BAD_PARAMETER;
 522
 523         if (function != ACPI_READ && function != ACPI_WRITE)
 524                 return AE_BAD_PARAMETER;
 525
 526         if (bits != 8 && acpi_strict)
 527                 return AE_BAD_PARAMETER;
 528
 529         while (bits - i > 0) {
 530                 if (function == ACPI_READ) {
 531                         result = acpi_ec_read(ec, address, &temp);
 532                         (*value) |= ((acpi_integer)temp) << i;
 533                 } else {
 534                         temp = 0xff & ((*value) >> i);
 535                         result = acpi_ec_write(ec, address, temp);
 536                 }
 537                 i += 8;
 538                 ++address;
 539         }
 540
 541         switch (result) {
 542         case -EINVAL:
 543                 return AE_BAD_PARAMETER;
 544                 break;
 545         case -ENODEV:
 546                 return AE_NOT_FOUND;
 547                 break;
 548         case -ETIME:
 549                 return AE_TIME;
 550                 break;
 551         default:
 552                 return AE_OK;
 553         }
 554 }
 555
 556 /* --------------------------------------------------------------------------
 557                               FS Interface (/proc)
 558    -------------------------------------------------------------------------- */
 559
 560 static struct proc_dir_entry *acpi_ec_dir;
 561
 562 static int acpi_ec_read_info(struct seq_file *seq, void *offset)
 563 {
 564         struct acpi_ec *ec = seq->private;
 565
 566         if (!ec)
 567                 goto end;
 568
 569         seq_printf(seq, "gpe:\t\t\t0x%02x\n", (u32) ec->gpe);
 570         seq_printf(seq, "ports:\t\t\t0x%02x, 0x%02x\n",
 571                    (unsigned)ec->command_addr, (unsigned)ec->data_addr);
 572         seq_printf(seq, "use global lock:\t%s\n",
 573                    ec->global_lock ? "yes" : "no");
 574       end:
 575         return 0;
 576 }
 577
 578 static int acpi_ec_info_open_fs(struct inode *inode, struct file *file)
 579 {
 580         return single_open(file, acpi_ec_read_info, PDE(inode)->data);
 581 }
 582
 583 static struct file_operations acpi_ec_info_ops = {
 584         .open = acpi_ec_info_open_fs,
 585         .read = seq_read,
 586         .llseek = seq_lseek,
 587         .release = single_release,
 588         .owner = THIS_MODULE,
 589 };
 590
 591 static int acpi_ec_add_fs(struct acpi_device *device)
 592 {
 593         struct proc_dir_entry *entry = NULL;
 594
 595         if (!acpi_device_dir(device)) {
 596                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
 597                                                      acpi_ec_dir);
 598                 if (!acpi_device_dir(device))
 599                         return -ENODEV;
 600         }
 601
 602         entry = create_proc_entry(ACPI_EC_FILE_INFO, S_IRUGO,
 603                                   acpi_device_dir(device));
 604         if (!entry)
 605                 return -ENODEV;
 606         else {
 607                 entry->proc_fops = &acpi_ec_info_ops;
 608                 entry->data = acpi_driver_data(device);
 609                 entry->owner = THIS_MODULE;
 610         }
 611
 612         return 0;
 613 }
 614
 615 static int acpi_ec_remove_fs(struct acpi_device *device)
 616 {
 617
 618         if (acpi_device_dir(device)) {
 619                 remove_proc_entry(ACPI_EC_FILE_INFO, acpi_device_dir(device));
 620                 remove_proc_entry(acpi_device_bid(device), acpi_ec_dir);
 621                 acpi_device_dir(device) = NULL;
 622         }
 623
 624         return 0;
 625 }
 626
 627 /* --------------------------------------------------------------------------
 628                                Driver Interface
 629    -------------------------------------------------------------------------- */
 630 static acpi_status
 631 ec_parse_io_ports(struct acpi_resource *resource, void *context);
 632
 633 static struct acpi_ec *make_acpi_ec(void)
 634 {
 635         struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
 636         if (!ec)
 637                 return NULL;
 638         ec->flags = 1 << EC_FLAGS_QUERY_PENDING;
 639         mutex_init(&ec->lock);
 640         init_waitqueue_head(&ec->wait);
 641         INIT_LIST_HEAD(&ec->list);
 642         return ec;
 643 }
 644
 645 static acpi_status
 646 acpi_ec_register_query_methods(acpi_handle handle, u32 level,
 647                                void *context, void **return_value)
 648 {
 649         struct acpi_namespace_node *node = handle;
 650         struct acpi_ec *ec = context;
 651         int value = 0;
 652         if (sscanf(node->name.ascii, "_Q%x", &value) == 1) {
 653                 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL);
 654         }
 655         return AE_OK;
 656 }
 657
 658 static acpi_status
 659 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
 660 {
 661         acpi_status status;
 662
 663         struct acpi_ec *ec = context;
 664         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
 665                                      ec_parse_io_ports, ec);
 666         if (ACPI_FAILURE(status))
 667                 return status;
 668
 669         /* Get GPE bit assignment (EC events). */
 670         /* TODO: Add support for _GPE returning a package */
 671         status = acpi_evaluate_integer(handle, "_GPE", NULL, &ec->gpe);
 672         if (ACPI_FAILURE(status))
 673                 return status;
 674         /* Find and register all query methods */
 675         acpi_walk_namespace(ACPI_TYPE_METHOD, handle, 1,
 676                             acpi_ec_register_query_methods, ec, NULL);
 677         /* Use the global lock for all EC transactions? */
 678         acpi_evaluate_integer(handle, "_GLK", NULL, &ec->global_lock);
 679         ec->handle = handle;
 680         return AE_CTRL_TERMINATE;
 681 }
 682
 683 static void ec_remove_handlers(struct acpi_ec *ec)
 684 {
 685         if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle,
 686                                 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler)))
 687                 printk(KERN_ERR PREFIX "failed to remove space handler\n");
 688         if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe,
 689                                 &acpi_ec_gpe_handler)))
 690                 printk(KERN_ERR PREFIX "failed to remove gpe handler\n");
 691         ec->handlers_installed = 0;
 692 }
 693
 694 static int acpi_ec_add(struct acpi_device *device)
 695 {
 696         struct acpi_ec *ec = NULL;
 697
 698         if (!device)
 699                 return -EINVAL;
 700         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
 701         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
 702
 703         /* Check for boot EC */
 704         if (boot_ec) {
 705                 if (boot_ec->handle == device->handle) {
 706                         /* Pre-loaded EC from DSDT, just move pointer */
 707                         ec = boot_ec;
 708                         boot_ec = NULL;
 709                         goto end;
 710                 } else if (boot_ec->handle == ACPI_ROOT_OBJECT) {
 711                         /* ECDT-based EC, time to shut it down */
 712                         ec_remove_handlers(boot_ec);
 713                         kfree(boot_ec);
 714                         first_ec = boot_ec = NULL;
 715                 }
 716         }
 717
 718         ec = make_acpi_ec();
 719         if (!ec)
 720                 return -ENOMEM;
 721
 722         if (ec_parse_device(device->handle, 0, ec, NULL) !=
 723             AE_CTRL_TERMINATE) {
 724                 kfree(ec);
 725                 return -EINVAL;
 726         }
 727         ec->handle = device->handle;
 728       end:
 729         if (!first_ec)
 730                 first_ec = ec;
 731         acpi_driver_data(device) = ec;
 732         acpi_ec_add_fs(device);
 733         printk(KERN_INFO PREFIX "GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n",
 734                           ec->gpe, ec->command_addr, ec->data_addr);
 735         return 0;
 736 }
 737
 738 static int acpi_ec_remove(struct acpi_device *device, int type)
 739 {
 740         struct acpi_ec *ec;
 741         struct acpi_ec_query_handler *handler, *tmp;
 742
 743         if (!device)
 744                 return -EINVAL;
 745
 746         ec = acpi_driver_data(device);
 747         mutex_lock(&ec->lock);
 748         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
 749                 list_del(&handler->node);
 750                 kfree(handler);
 751         }
 752         mutex_unlock(&ec->lock);
 753         acpi_ec_remove_fs(device);
 754         acpi_driver_data(device) = NULL;
 755         if (ec == first_ec)
 756                 first_ec = NULL;
 757         kfree(ec);
 758         return 0;
 759 }
 760
 761 static acpi_status
 762 ec_parse_io_ports(struct acpi_resource *resource, void *context)
 763 {
 764         struct acpi_ec *ec = context;
 765
 766         if (resource->type != ACPI_RESOURCE_TYPE_IO)
 767                 return AE_OK;
 768
 769         /*
 770          * The first address region returned is the data port, and
 771          * the second address region returned is the status/command
 772          * port.
 773          */
 774         if (ec->data_addr == 0)
 775                 ec->data_addr = resource->data.io.minimum;
 776         else if (ec->command_addr == 0)
 777                 ec->command_addr = resource->data.io.minimum;
 778         else
 779                 return AE_CTRL_TERMINATE;
 780
 781         return AE_OK;
 782 }
 783
 784 static int ec_install_handlers(struct acpi_ec *ec)
 785 {
 786         acpi_status status;
 787         if (ec->handlers_installed)
 788                 return 0;
 789         status = acpi_install_gpe_handler(NULL, ec->gpe,
 790                                           ACPI_GPE_EDGE_TRIGGERED,
 791                                           &acpi_ec_gpe_handler, ec);
 792         if (ACPI_FAILURE(status))
 793                 return -ENODEV;
 794
 795         acpi_set_gpe_type(NULL, ec->gpe, ACPI_GPE_TYPE_RUNTIME);
 796         acpi_enable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
 797
 798         status = acpi_install_address_space_handler(ec->handle,
 799                                                     ACPI_ADR_SPACE_EC,
 800                                                     &acpi_ec_space_handler,
 801                                                     &acpi_ec_space_setup, ec);
 802         if (ACPI_FAILURE(status)) {
 803                 acpi_remove_gpe_handler(NULL, ec->gpe, &acpi_ec_gpe_handler);
 804                 return -ENODEV;
 805         }
 806
 807         ec->handlers_installed = 1;
 808         return 0;
 809 }
 810
 811 static int acpi_ec_start(struct acpi_device *device)
 812 {
 813         struct acpi_ec *ec;
 814         int ret = 0;
 815
 816         if (!device)
 817                 return -EINVAL;
 818
 819         ec = acpi_driver_data(device);
 820
 821         if (!ec)
 822                 return -EINVAL;
 823
 824         ret = ec_install_handlers(ec);
 825
 826         /* EC is fully operational, allow queries */
 827         clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
 828         return ret;
 829 }
 830
 831 static int acpi_ec_stop(struct acpi_device *device, int type)
 832 {
 833         struct acpi_ec *ec;
 834         if (!device)
 835                 return -EINVAL;
 836         ec = acpi_driver_data(device);
 837         if (!ec)
 838                 return -EINVAL;
 839         ec_remove_handlers(ec);
 840
 841         return 0;
 842 }
 843
 844 int __init acpi_ec_ecdt_probe(void)
 845 {
 846         int ret;
 847         acpi_status status;
 848         struct acpi_table_ecdt *ecdt_ptr;
 849
 850         boot_ec = make_acpi_ec();
 851         if (!boot_ec)
 852                 return -ENOMEM;
 853         /*
 854          * Generate a boot ec context
 855          */
 856         status = acpi_get_table(ACPI_SIG_ECDT, 1,
 857                                 (struct acpi_table_header **)&ecdt_ptr);
 858         if (ACPI_SUCCESS(status)) {
 859                 printk(KERN_INFO PREFIX "EC description table is found, configuring boot EC\n");
 860                 boot_ec->command_addr = ecdt_ptr->control.address;
 861                 boot_ec->data_addr = ecdt_ptr->data.address;
 862                 boot_ec->gpe = ecdt_ptr->gpe;
 863                 boot_ec->handle = ACPI_ROOT_OBJECT;
 864         } else {
 865                 printk(KERN_DEBUG PREFIX "Look up EC in DSDT\n");
 866                 status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device,
 867                                                 boot_ec, NULL);
 868                 /* Check that acpi_get_devices actually find something */
 869                 if (ACPI_FAILURE(status) || !boot_ec->handle)
 870                         goto error;
 871         }
 872
 873         ret = ec_install_handlers(boot_ec);
 874         if (!ret) {
 875                 first_ec = boot_ec;
 876                 return 0;
 877         }
 878       error:
 879         kfree(boot_ec);
 880         boot_ec = NULL;
 881         return -ENODEV;
 882 }
 883
 884 static int __init acpi_ec_init(void)
 885 {
 886         int result = 0;
 887
 888         if (acpi_disabled)
 889                 return 0;
 890
 891         acpi_ec_dir = proc_mkdir(ACPI_EC_CLASS, acpi_root_dir);
 892         if (!acpi_ec_dir)
 893                 return -ENODEV;
 894
 895         /* Now register the driver for the EC */
 896         result = acpi_bus_register_driver(&acpi_ec_driver);
 897         if (result < 0) {
 898                 remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
 899                 return -ENODEV;
 900         }
 901
 902         return result;
 903 }
 904
 905 subsys_initcall(acpi_ec_init);
 906
 907 /* EC driver currently not unloadable */
 908 #if 0
 909 static void __exit acpi_ec_exit(void)
 910 {
 911
 912         acpi_bus_unregister_driver(&acpi_ec_driver);
 913
 914         remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
 915
 916         return;
 917 }
 918 #endif  /* 0 */