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         /* Make sure GPE is enabled before doing transaction */
 262         acpi_enable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
 263
 264         status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBF_0, 0);
 265         if (status) {
 266                 printk(KERN_ERR PREFIX
 267                        "input buffer is not empty, aborting transaction\n");
 268                 goto end;
 269         }
 270
 271         status = acpi_ec_transaction_unlocked(ec, command,
 272                                               wdata, wdata_len,
 273                                               rdata, rdata_len,
 274                                               force_poll);
 275
 276       end:
 277
 278         if (ec->global_lock)
 279                 acpi_release_global_lock(glk);
 280         mutex_unlock(&ec->lock);
 281
 282         return status;
 283 }
 284
 285 /*
 286  * Note: samsung nv5000 doesn't work with ec burst mode.
 287  * http://bugzilla.kernel.org/show_bug.cgi?id=4980
 288  */
 289 int acpi_ec_burst_enable(struct acpi_ec *ec)
 290 {
 291         u8 d;
 292         return acpi_ec_transaction(ec, ACPI_EC_BURST_ENABLE, NULL, 0, &d, 1, 0);
 293 }
 294
 295 int acpi_ec_burst_disable(struct acpi_ec *ec)
 296 {
 297         return acpi_ec_transaction(ec, ACPI_EC_BURST_DISABLE, NULL, 0, NULL, 0, 0);
 298 }
 299
 300 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 * data)
 301 {
 302         int result;
 303         u8 d;
 304
 305         result = acpi_ec_transaction(ec, ACPI_EC_COMMAND_READ,
 306                                      &address, 1, &d, 1, 0);
 307         *data = d;
 308         return result;
 309 }
 310
 311 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
 312 {
 313         u8 wdata[2] = { address, data };
 314         return acpi_ec_transaction(ec, ACPI_EC_COMMAND_WRITE,
 315                                    wdata, 2, NULL, 0, 0);
 316 }
 317
 318 /*
 319  * Externally callable EC access functions. For now, assume 1 EC only
 320  */
 321 int ec_burst_enable(void)
 322 {
 323         if (!first_ec)
 324                 return -ENODEV;
 325         return acpi_ec_burst_enable(first_ec);
 326 }
 327
 328 EXPORT_SYMBOL(ec_burst_enable);
 329
 330 int ec_burst_disable(void)
 331 {
 332         if (!first_ec)
 333                 return -ENODEV;
 334         return acpi_ec_burst_disable(first_ec);
 335 }
 336
 337 EXPORT_SYMBOL(ec_burst_disable);
 338
 339 int ec_read(u8 addr, u8 * val)
 340 {
 341         int err;
 342         u8 temp_data;
 343
 344         if (!first_ec)
 345                 return -ENODEV;
 346
 347         err = acpi_ec_read(first_ec, addr, &temp_data);
 348
 349         if (!err) {
 350                 *val = temp_data;
 351                 return 0;
 352         } else
 353                 return err;
 354 }
 355
 356 EXPORT_SYMBOL(ec_read);
 357
 358 int ec_write(u8 addr, u8 val)
 359 {
 360         int err;
 361
 362         if (!first_ec)
 363                 return -ENODEV;
 364
 365         err = acpi_ec_write(first_ec, addr, val);
 366
 367         return err;
 368 }
 369
 370 EXPORT_SYMBOL(ec_write);
 371
 372 int ec_transaction(u8 command,
 373                    const u8 * wdata, unsigned wdata_len,
 374                    u8 * rdata, unsigned rdata_len,
 375                    int force_poll)
 376 {
 377         if (!first_ec)
 378                 return -ENODEV;
 379
 380         return acpi_ec_transaction(first_ec, command, wdata,
 381                                    wdata_len, rdata, rdata_len,
 382                                    force_poll);
 383 }
 384
 385 EXPORT_SYMBOL(ec_transaction);
 386
 387 static int acpi_ec_query(struct acpi_ec *ec, u8 * data)
 388 {
 389         int result;
 390         u8 d;
 391
 392         if (!ec || !data)
 393                 return -EINVAL;
 394
 395         /*
 396          * Query the EC to find out which _Qxx method we need to evaluate.
 397          * Note that successful completion of the query causes the ACPI_EC_SCI
 398          * bit to be cleared (and thus clearing the interrupt source).
 399          */
 400
 401         result = acpi_ec_transaction(ec, ACPI_EC_COMMAND_QUERY, NULL, 0, &d, 1, 0);
 402         if (result)
 403                 return result;
 404
 405         if (!d)
 406                 return -ENODATA;
 407
 408         *data = d;
 409         return 0;
 410 }
 411
 412 /* --------------------------------------------------------------------------
 413                                 Event Management
 414    -------------------------------------------------------------------------- */
 415 int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
 416                               acpi_handle handle, acpi_ec_query_func func,
 417                               void *data)
 418 {
 419         struct acpi_ec_query_handler *handler =
 420             kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL);
 421         if (!handler)
 422                 return -ENOMEM;
 423
 424         handler->query_bit = query_bit;
 425         handler->handle = handle;
 426         handler->func = func;
 427         handler->data = data;
 428         mutex_lock(&ec->lock);
 429         list_add(&handler->node, &ec->list);
 430         mutex_unlock(&ec->lock);
 431         return 0;
 432 }
 433
 434 EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler);
 435
 436 void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit)
 437 {
 438         struct acpi_ec_query_handler *handler;
 439         mutex_lock(&ec->lock);
 440         list_for_each_entry(handler, &ec->list, node) {
 441                 if (query_bit == handler->query_bit) {
 442                         list_del(&handler->node);
 443                         kfree(handler);
 444                 }
 445         }
 446         mutex_unlock(&ec->lock);
 447 }
 448
 449 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler);
 450
 451 static void acpi_ec_gpe_query(void *ec_cxt)
 452 {
 453         struct acpi_ec *ec = ec_cxt;
 454         u8 value = 0;
 455         struct acpi_ec_query_handler *handler, copy;
 456
 457         if (!ec || acpi_ec_query(ec, &value))
 458                 return;
 459         mutex_lock(&ec->lock);
 460         list_for_each_entry(handler, &ec->list, node) {
 461                 if (value == handler->query_bit) {
 462                         /* have custom handler for this bit */
 463                         memcpy(&copy, handler, sizeof(copy));
 464                         mutex_unlock(&ec->lock);
 465                         if (copy.func) {
 466                                 copy.func(copy.data);
 467                         } else if (copy.handle) {
 468                                 acpi_evaluate_object(copy.handle, NULL, NULL, NULL);
 469                         }
 470                         return;
 471                 }
 472         }
 473         mutex_unlock(&ec->lock);
 474 }
 475
 476 static u32 acpi_ec_gpe_handler(void *data)
 477 {
 478         acpi_status status = AE_OK;
 479         struct acpi_ec *ec = data;
 480
 481         clear_bit(EC_FLAGS_WAIT_GPE, &ec->flags);
 482         if (test_bit(EC_FLAGS_GPE_MODE, &ec->flags))
 483                 wake_up(&ec->wait);
 484
 485         if (acpi_ec_read_status(ec) & ACPI_EC_FLAG_SCI) {
 486                 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags))
 487                         status = acpi_os_execute(OSL_EC_BURST_HANDLER,
 488                                 acpi_ec_gpe_query, ec);
 489         } else if (unlikely(!test_bit(EC_FLAGS_GPE_MODE, &ec->flags)))
 490                 set_bit(EC_FLAGS_GPE_MODE, &ec->flags);
 491
 492         return ACPI_SUCCESS(status) ?
 493             ACPI_INTERRUPT_HANDLED : ACPI_INTERRUPT_NOT_HANDLED;
 494 }
 495
 496 /* --------------------------------------------------------------------------
 497                              Address Space Management
 498    -------------------------------------------------------------------------- */
 499
 500 static acpi_status
 501 acpi_ec_space_setup(acpi_handle region_handle,
 502                     u32 function, void *handler_context, void **return_context)
 503 {
 504         /*
 505          * The EC object is in the handler context and is needed
 506          * when calling the acpi_ec_space_handler.
 507          */
 508         *return_context = (function != ACPI_REGION_DEACTIVATE) ?
 509             handler_context : NULL;
 510
 511         return AE_OK;
 512 }
 513
 514 static acpi_status
 515 acpi_ec_space_handler(u32 function, acpi_physical_address address,
 516                       u32 bits, acpi_integer *value,
 517                       void *handler_context, void *region_context)
 518 {
 519         struct acpi_ec *ec = handler_context;
 520         int result = 0, i = 0;
 521         u8 temp = 0;
 522
 523         if ((address > 0xFF) || !value || !handler_context)
 524                 return AE_BAD_PARAMETER;
 525
 526         if (function != ACPI_READ && function != ACPI_WRITE)
 527                 return AE_BAD_PARAMETER;
 528
 529         if (bits != 8 && acpi_strict)
 530                 return AE_BAD_PARAMETER;
 531
 532         while (bits - i > 0) {
 533                 if (function == ACPI_READ) {
 534                         result = acpi_ec_read(ec, address, &temp);
 535                         (*value) |= ((acpi_integer)temp) << i;
 536                 } else {
 537                         temp = 0xff & ((*value) >> i);
 538                         result = acpi_ec_write(ec, address, temp);
 539                 }
 540                 i += 8;
 541                 ++address;
 542         }
 543
 544         switch (result) {
 545         case -EINVAL:
 546                 return AE_BAD_PARAMETER;
 547                 break;
 548         case -ENODEV:
 549                 return AE_NOT_FOUND;
 550                 break;
 551         case -ETIME:
 552                 return AE_TIME;
 553                 break;
 554         default:
 555                 return AE_OK;
 556         }
 557 }
 558
 559 /* --------------------------------------------------------------------------
 560                               FS Interface (/proc)
 561    -------------------------------------------------------------------------- */
 562
 563 static struct proc_dir_entry *acpi_ec_dir;
 564
 565 static int acpi_ec_read_info(struct seq_file *seq, void *offset)
 566 {
 567         struct acpi_ec *ec = seq->private;
 568
 569         if (!ec)
 570                 goto end;
 571
 572         seq_printf(seq, "gpe:\t\t\t0x%02x\n", (u32) ec->gpe);
 573         seq_printf(seq, "ports:\t\t\t0x%02x, 0x%02x\n",
 574                    (unsigned)ec->command_addr, (unsigned)ec->data_addr);
 575         seq_printf(seq, "use global lock:\t%s\n",
 576                    ec->global_lock ? "yes" : "no");
 577       end:
 578         return 0;
 579 }
 580
 581 static int acpi_ec_info_open_fs(struct inode *inode, struct file *file)
 582 {
 583         return single_open(file, acpi_ec_read_info, PDE(inode)->data);
 584 }
 585
 586 static struct file_operations acpi_ec_info_ops = {
 587         .open = acpi_ec_info_open_fs,
 588         .read = seq_read,
 589         .llseek = seq_lseek,
 590         .release = single_release,
 591         .owner = THIS_MODULE,
 592 };
 593
 594 static int acpi_ec_add_fs(struct acpi_device *device)
 595 {
 596         struct proc_dir_entry *entry = NULL;
 597
 598         if (!acpi_device_dir(device)) {
 599                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
 600                                                      acpi_ec_dir);
 601                 if (!acpi_device_dir(device))
 602                         return -ENODEV;
 603         }
 604
 605         entry = create_proc_entry(ACPI_EC_FILE_INFO, S_IRUGO,
 606                                   acpi_device_dir(device));
 607         if (!entry)
 608                 return -ENODEV;
 609         else {
 610                 entry->proc_fops = &acpi_ec_info_ops;
 611                 entry->data = acpi_driver_data(device);
 612                 entry->owner = THIS_MODULE;
 613         }
 614
 615         return 0;
 616 }
 617
 618 static int acpi_ec_remove_fs(struct acpi_device *device)
 619 {
 620
 621         if (acpi_device_dir(device)) {
 622                 remove_proc_entry(ACPI_EC_FILE_INFO, acpi_device_dir(device));
 623                 remove_proc_entry(acpi_device_bid(device), acpi_ec_dir);
 624                 acpi_device_dir(device) = NULL;
 625         }
 626
 627         return 0;
 628 }
 629
 630 /* --------------------------------------------------------------------------
 631                                Driver Interface
 632    -------------------------------------------------------------------------- */
 633 static acpi_status
 634 ec_parse_io_ports(struct acpi_resource *resource, void *context);
 635
 636 static struct acpi_ec *make_acpi_ec(void)
 637 {
 638         struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
 639         if (!ec)
 640                 return NULL;
 641
 642         ec->flags = 1 << EC_FLAGS_QUERY_PENDING;
 643         mutex_init(&ec->lock);
 644         init_waitqueue_head(&ec->wait);
 645         INIT_LIST_HEAD(&ec->list);
 646
 647         return ec;
 648 }
 649
 650 static acpi_status
 651 acpi_ec_register_query_methods(acpi_handle handle, u32 level,
 652                                void *context, void **return_value)
 653 {
 654         struct acpi_namespace_node *node = handle;
 655         struct acpi_ec *ec = context;
 656         int value = 0;
 657         if (sscanf(node->name.ascii, "_Q%x", &value) == 1) {
 658                 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL);
 659         }
 660         return AE_OK;
 661 }
 662
 663 static acpi_status
 664 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
 665 {
 666         acpi_status status;
 667
 668         struct acpi_ec *ec = context;
 669         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
 670                                      ec_parse_io_ports, ec);
 671         if (ACPI_FAILURE(status))
 672                 return status;
 673
 674         /* Get GPE bit assignment (EC events). */
 675         /* TODO: Add support for _GPE returning a package */
 676         status = acpi_evaluate_integer(handle, "_GPE", NULL, &ec->gpe);
 677         if (ACPI_FAILURE(status))
 678                 return status;
 679         /* Find and register all query methods */
 680         acpi_walk_namespace(ACPI_TYPE_METHOD, handle, 1,
 681                             acpi_ec_register_query_methods, ec, NULL);
 682         /* Use the global lock for all EC transactions? */
 683         acpi_evaluate_integer(handle, "_GLK", NULL, &ec->global_lock);
 684         ec->handle = handle;
 685         return AE_CTRL_TERMINATE;
 686 }
 687
 688 static void ec_remove_handlers(struct acpi_ec *ec)
 689 {
 690         if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle,
 691                                 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler)))
 692                 printk(KERN_ERR PREFIX "failed to remove space handler\n");
 693         if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe,
 694                                 &acpi_ec_gpe_handler)))
 695                 printk(KERN_ERR PREFIX "failed to remove gpe handler\n");
 696         ec->handlers_installed = 0;
 697 }
 698
 699 static int acpi_ec_add(struct acpi_device *device)
 700 {
 701         struct acpi_ec *ec = NULL;
 702
 703         if (!device)
 704                 return -EINVAL;
 705         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
 706         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
 707
 708         /* Check for boot EC */
 709         if (boot_ec) {
 710                 if (boot_ec->handle == device->handle) {
 711                         /* Pre-loaded EC from DSDT, just move pointer */
 712                         ec = boot_ec;
 713                         boot_ec = NULL;
 714                         goto end;
 715                 } else if (boot_ec->handle == ACPI_ROOT_OBJECT) {
 716                         /* ECDT-based EC, time to shut it down */
 717                         ec_remove_handlers(boot_ec);
 718                         kfree(boot_ec);
 719                         first_ec = boot_ec = NULL;
 720                 }
 721         }
 722
 723         ec = make_acpi_ec();
 724         if (!ec)
 725                 return -ENOMEM;
 726
 727         if (ec_parse_device(device->handle, 0, ec, NULL) !=
 728             AE_CTRL_TERMINATE) {
 729                 kfree(ec);
 730                 return -EINVAL;
 731         }
 732         ec->handle = device->handle;
 733       end:
 734         if (!first_ec)
 735                 first_ec = ec;
 736         acpi_driver_data(device) = ec;
 737         acpi_ec_add_fs(device);
 738         printk(KERN_INFO PREFIX "GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n",
 739                           ec->gpe, ec->command_addr, ec->data_addr);
 740         return 0;
 741 }
 742
 743 static int acpi_ec_remove(struct acpi_device *device, int type)
 744 {
 745         struct acpi_ec *ec;
 746         struct acpi_ec_query_handler *handler, *tmp;
 747
 748         if (!device)
 749                 return -EINVAL;
 750
 751         ec = acpi_driver_data(device);
 752         mutex_lock(&ec->lock);
 753         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
 754                 list_del(&handler->node);
 755                 kfree(handler);
 756         }
 757         mutex_unlock(&ec->lock);
 758         acpi_ec_remove_fs(device);
 759         acpi_driver_data(device) = NULL;
 760         if (ec == first_ec)
 761                 first_ec = NULL;
 762         kfree(ec);
 763         return 0;
 764 }
 765
 766 static acpi_status
 767 ec_parse_io_ports(struct acpi_resource *resource, void *context)
 768 {
 769         struct acpi_ec *ec = context;
 770
 771         if (resource->type != ACPI_RESOURCE_TYPE_IO)
 772                 return AE_OK;
 773
 774         /*
 775          * The first address region returned is the data port, and
 776          * the second address region returned is the status/command
 777          * port.
 778          */
 779         if (ec->data_addr == 0)
 780                 ec->data_addr = resource->data.io.minimum;
 781         else if (ec->command_addr == 0)
 782                 ec->command_addr = resource->data.io.minimum;
 783         else
 784                 return AE_CTRL_TERMINATE;
 785
 786         return AE_OK;
 787 }
 788
 789 static int ec_install_handlers(struct acpi_ec *ec)
 790 {
 791         acpi_status status;
 792         if (ec->handlers_installed)
 793                 return 0;
 794         status = acpi_install_gpe_handler(NULL, ec->gpe,
 795                                           ACPI_GPE_EDGE_TRIGGERED,
 796                                           &acpi_ec_gpe_handler, ec);
 797         if (ACPI_FAILURE(status))
 798                 return -ENODEV;
 799
 800         acpi_set_gpe_type(NULL, ec->gpe, ACPI_GPE_TYPE_RUNTIME);
 801         acpi_enable_gpe(NULL, ec->gpe, ACPI_NOT_ISR);
 802
 803         status = acpi_install_address_space_handler(ec->handle,
 804                                                     ACPI_ADR_SPACE_EC,
 805                                                     &acpi_ec_space_handler,
 806                                                     &acpi_ec_space_setup, ec);
 807         if (ACPI_FAILURE(status)) {
 808                 acpi_remove_gpe_handler(NULL, ec->gpe, &acpi_ec_gpe_handler);
 809                 return -ENODEV;
 810         }
 811
 812         ec->handlers_installed = 1;
 813         return 0;
 814 }
 815
 816 static int acpi_ec_start(struct acpi_device *device)
 817 {
 818         struct acpi_ec *ec;
 819         int ret = 0;
 820
 821         if (!device)
 822                 return -EINVAL;
 823
 824         ec = acpi_driver_data(device);
 825
 826         if (!ec)
 827                 return -EINVAL;
 828
 829         ret = ec_install_handlers(ec);
 830
 831         /* EC is fully operational, allow queries */
 832         clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
 833         return ret;
 834 }
 835
 836 static int acpi_ec_stop(struct acpi_device *device, int type)
 837 {
 838         struct acpi_ec *ec;
 839         if (!device)
 840                 return -EINVAL;
 841         ec = acpi_driver_data(device);
 842         if (!ec)
 843                 return -EINVAL;
 844         ec_remove_handlers(ec);
 845
 846         return 0;
 847 }
 848
 849 int __init acpi_ec_ecdt_probe(void)
 850 {
 851         int ret;
 852         acpi_status status;
 853         struct acpi_table_ecdt *ecdt_ptr;
 854
 855         boot_ec = make_acpi_ec();
 856         if (!boot_ec)
 857                 return -ENOMEM;
 858         /*
 859          * Generate a boot ec context
 860          */
 861         status = acpi_get_table(ACPI_SIG_ECDT, 1,
 862                                 (struct acpi_table_header **)&ecdt_ptr);
 863         if (ACPI_SUCCESS(status)) {
 864                 printk(KERN_INFO PREFIX "EC description table is found, configuring boot EC\n");
 865                 boot_ec->command_addr = ecdt_ptr->control.address;
 866                 boot_ec->data_addr = ecdt_ptr->data.address;
 867                 boot_ec->gpe = ecdt_ptr->gpe;
 868                 boot_ec->handle = ACPI_ROOT_OBJECT;
 869         } else {
 870                 printk(KERN_DEBUG PREFIX "Look up EC in DSDT\n");
 871                 status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device,
 872                                                 boot_ec, NULL);
 873                 /* Check that acpi_get_devices actually find something */
 874                 if (ACPI_FAILURE(status) || !boot_ec->handle)
 875                         goto error;
 876         }
 877
 878         ret = ec_install_handlers(boot_ec);
 879         if (!ret) {
 880                 first_ec = boot_ec;
 881                 return 0;
 882         }
 883       error:
 884         kfree(boot_ec);
 885         boot_ec = NULL;
 886         return -ENODEV;
 887 }
 888
 889 static int __init acpi_ec_init(void)
 890 {
 891         int result = 0;
 892
 893         if (acpi_disabled)
 894                 return 0;
 895
 896         acpi_ec_dir = proc_mkdir(ACPI_EC_CLASS, acpi_root_dir);
 897         if (!acpi_ec_dir)
 898                 return -ENODEV;
 899
 900         /* Now register the driver for the EC */
 901         result = acpi_bus_register_driver(&acpi_ec_driver);
 902         if (result < 0) {
 903                 remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
 904                 return -ENODEV;
 905         }
 906
 907         return result;
 908 }
 909
 910 subsys_initcall(acpi_ec_init);
 911
 912 /* EC driver currently not unloadable */
 913 #if 0
 914 static void __exit acpi_ec_exit(void)
 915 {
 916
 917         acpi_bus_unregister_driver(&acpi_ec_driver);
 918
 919         remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
 920
 921         return;
 922 }
 923 #endif  /* 0 */