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   1 /*
   2  *  ec.c - ACPI Embedded Controller Driver (v2.1)
   3  *
   4  *  Copyright (C) 2006-2008 Alexey Starikovskiy <astarikovskiy@suse.de>
   5  *  Copyright (C) 2006 Denis Sadykov <denis.m.sadykov@intel.com>
   6  *  Copyright (C) 2004 Luming Yu <luming.yu@intel.com>
   7  *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
   8  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
   9  *
  10  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  11  *
  12  *  This program is free software; you can redistribute it and/or modify
  13  *  it under the terms of the GNU General Public License as published by
  14  *  the Free Software Foundation; either version 2 of the License, or (at
  15  *  your option) any later version.
  16  *
  17  *  This program is distributed in the hope that it will be useful, but
  18  *  WITHOUT ANY WARRANTY; without even the implied warranty of
  19  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  20  *  General Public License for more details.
  21  *
  22  *  You should have received a copy of the GNU General Public License along
  23  *  with this program; if not, write to the Free Software Foundation, Inc.,
  24  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
  25  *
  26  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  27  */
  28
  29 /* Uncomment next line to get verbose printout */
  30 /* #define DEBUG */
  31
  32 #include <linux/kernel.h>
  33 #include <linux/module.h>
  34 #include <linux/init.h>
  35 #include <linux/types.h>
  36 #include <linux/delay.h>
  37 #include <linux/proc_fs.h>
  38 #include <linux/seq_file.h>
  39 #include <linux/interrupt.h>
  40 #include <linux/list.h>
  41 #include <linux/spinlock.h>
  42 #include <asm/io.h>
  43 #include <acpi/acpi_bus.h>
  44 #include <acpi/acpi_drivers.h>
  45 #include <linux/dmi.h>
  46
  47 #define ACPI_EC_CLASS                   "embedded_controller"
  48 #define ACPI_EC_DEVICE_NAME             "Embedded Controller"
  49 #define ACPI_EC_FILE_INFO               "info"
  50
  51 #define PREFIX                          "ACPI: EC: "
  52
  53 /* EC status register */
  54 #define ACPI_EC_FLAG_OBF        0x01    /* Output buffer full */
  55 #define ACPI_EC_FLAG_IBF        0x02    /* Input buffer full */
  56 #define ACPI_EC_FLAG_BURST      0x10    /* burst mode */
  57 #define ACPI_EC_FLAG_SCI        0x20    /* EC-SCI occurred */
  58
  59 /* EC commands */
  60 enum ec_command {
  61         ACPI_EC_COMMAND_READ = 0x80,
  62         ACPI_EC_COMMAND_WRITE = 0x81,
  63         ACPI_EC_BURST_ENABLE = 0x82,
  64         ACPI_EC_BURST_DISABLE = 0x83,
  65         ACPI_EC_COMMAND_QUERY = 0x84,
  66 };
  67
  68 #define ACPI_EC_DELAY           500     /* Wait 500ms max. during EC ops */
  69 #define ACPI_EC_UDELAY_GLK      1000    /* Wait 1ms max. to get global lock */
  70 #define ACPI_EC_CDELAY          10      /* Wait 10us before polling EC */
  71 #define ACPI_EC_MSI_UDELAY      550     /* Wait 550us for MSI EC */
  72
  73 #define ACPI_EC_STORM_THRESHOLD 8       /* number of false interrupts
  74                                            per one transaction */
  75
  76 enum {
  77         EC_FLAGS_QUERY_PENDING,         /* Query is pending */
  78         EC_FLAGS_GPE_STORM,             /* GPE storm detected */
  79         EC_FLAGS_HANDLERS_INSTALLED     /* Handlers for GPE and
  80                                          * OpReg are installed */
  81 };
  82
  83 /* If we find an EC via the ECDT, we need to keep a ptr to its context */
  84 /* External interfaces use first EC only, so remember */
  85 typedef int (*acpi_ec_query_func) (void *data);
  86
  87 struct acpi_ec_query_handler {
  88         struct list_head node;
  89         acpi_ec_query_func func;
  90         acpi_handle handle;
  91         void *data;
  92         u8 query_bit;
  93 };
  94
  95 struct transaction {
  96         const u8 *wdata;
  97         u8 *rdata;
  98         unsigned short irq_count;
  99         u8 command;
 100         u8 wi;
 101         u8 ri;
 102         u8 wlen;
 103         u8 rlen;
 104         bool done;
 105 };
 106
 107 static struct acpi_ec {
 108         acpi_handle handle;
 109         unsigned long gpe;
 110         unsigned long command_addr;
 111         unsigned long data_addr;
 112         unsigned long global_lock;
 113         unsigned long flags;
 114         struct mutex lock;
 115         wait_queue_head_t wait;
 116         struct list_head list;
 117         struct transaction *curr;
 118         spinlock_t curr_lock;
 119 } *boot_ec, *first_ec;
 120
 121 static int EC_FLAGS_MSI; /* Out-of-spec MSI controller */
 122
 123 /* --------------------------------------------------------------------------
 124                              Transaction Management
 125    -------------------------------------------------------------------------- */
 126
 127 static inline u8 acpi_ec_read_status(struct acpi_ec *ec)
 128 {
 129         u8 x = inb(ec->command_addr);
 130         pr_debug(PREFIX "---> status = 0x%2.2x\n", x);
 131         return x;
 132 }
 133
 134 static inline u8 acpi_ec_read_data(struct acpi_ec *ec)
 135 {
 136         u8 x = inb(ec->data_addr);
 137         pr_debug(PREFIX "---> data = 0x%2.2x\n", x);
 138         return x;
 139 }
 140
 141 static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command)
 142 {
 143         pr_debug(PREFIX "<--- command = 0x%2.2x\n", command);
 144         outb(command, ec->command_addr);
 145 }
 146
 147 static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data)
 148 {
 149         pr_debug(PREFIX "<--- data = 0x%2.2x\n", data);
 150         outb(data, ec->data_addr);
 151 }
 152
 153 static int ec_transaction_done(struct acpi_ec *ec)
 154 {
 155         unsigned long flags;
 156         int ret = 0;
 157         spin_lock_irqsave(&ec->curr_lock, flags);
 158         if (!ec->curr || ec->curr->done)
 159                 ret = 1;
 160         spin_unlock_irqrestore(&ec->curr_lock, flags);
 161         return ret;
 162 }
 163
 164 static void start_transaction(struct acpi_ec *ec)
 165 {
 166         ec->curr->irq_count = ec->curr->wi = ec->curr->ri = 0;
 167         ec->curr->done = false;
 168         acpi_ec_write_cmd(ec, ec->curr->command);
 169 }
 170
 171 static void advance_transaction(struct acpi_ec *ec, u8 status)
 172 {
 173         unsigned long flags;
 174         spin_lock_irqsave(&ec->curr_lock, flags);
 175         if (!ec->curr)
 176                 goto unlock;
 177         if (ec->curr->wlen > ec->curr->wi) {
 178                 if ((status & ACPI_EC_FLAG_IBF) == 0)
 179                         acpi_ec_write_data(ec,
 180                                 ec->curr->wdata[ec->curr->wi++]);
 181                 else
 182                         goto err;
 183         } else if (ec->curr->rlen > ec->curr->ri) {
 184                 if ((status & ACPI_EC_FLAG_OBF) == 1) {
 185                         ec->curr->rdata[ec->curr->ri++] = acpi_ec_read_data(ec);
 186                         if (ec->curr->rlen == ec->curr->ri)
 187                                 ec->curr->done = true;
 188                 } else
 189                         goto err;
 190         } else if (ec->curr->wlen == ec->curr->wi &&
 191                    (status & ACPI_EC_FLAG_IBF) == 0)
 192                 ec->curr->done = true;
 193         goto unlock;
 194 err:
 195         /* false interrupt, state didn't change */
 196         if (in_interrupt())
 197                 ++ec->curr->irq_count;
 198 unlock:
 199         spin_unlock_irqrestore(&ec->curr_lock, flags);
 200 }
 201
 202 static void acpi_ec_gpe_query(void *ec_cxt);
 203
 204 static int ec_check_sci(struct acpi_ec *ec, u8 state)
 205 {
 206         if (state & ACPI_EC_FLAG_SCI) {
 207                 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags))
 208                         return acpi_os_execute(OSL_EC_BURST_HANDLER,
 209                                 acpi_ec_gpe_query, ec);
 210         }
 211         return 0;
 212 }
 213
 214 static int ec_poll(struct acpi_ec *ec)
 215 {
 216         unsigned long flags;
 217         int repeat = 2; /* number of command restarts */
 218         while (repeat--) {
 219                 unsigned long delay = jiffies +
 220                         msecs_to_jiffies(ACPI_EC_DELAY);
 221                 do {
 222                         /* don't sleep with disabled interrupts */
 223                         if (EC_FLAGS_MSI || irqs_disabled()) {
 224                                 udelay(ACPI_EC_MSI_UDELAY);
 225                                 if (ec_transaction_done(ec))
 226                                         return 0;
 227                         } else {
 228                                 if (wait_event_timeout(ec->wait,
 229                                                 ec_transaction_done(ec),
 230                                                 msecs_to_jiffies(1)))
 231                                         return 0;
 232                         }
 233                         advance_transaction(ec, acpi_ec_read_status(ec));
 234                 } while (time_before(jiffies, delay));
 235                 if (acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF)
 236                         break;
 237                 pr_debug(PREFIX "controller reset, restart transaction\n");
 238                 spin_lock_irqsave(&ec->curr_lock, flags);
 239                 start_transaction(ec);
 240                 spin_unlock_irqrestore(&ec->curr_lock, flags);
 241         }
 242         return -ETIME;
 243 }
 244
 245 static int acpi_ec_transaction_unlocked(struct acpi_ec *ec,
 246                                         struct transaction *t)
 247 {
 248         unsigned long tmp;
 249         int ret = 0;
 250         pr_debug(PREFIX "transaction start\n");
 251         /* disable GPE during transaction if storm is detected */
 252         if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
 253                 acpi_disable_gpe(NULL, ec->gpe);
 254         }
 255         if (EC_FLAGS_MSI)
 256                 udelay(ACPI_EC_MSI_UDELAY);
 257         /* start transaction */
 258         spin_lock_irqsave(&ec->curr_lock, tmp);
 259         /* following two actions should be kept atomic */
 260         ec->curr = t;
 261         start_transaction(ec);
 262         if (ec->curr->command == ACPI_EC_COMMAND_QUERY)
 263                 clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
 264         spin_unlock_irqrestore(&ec->curr_lock, tmp);
 265         ret = ec_poll(ec);
 266         pr_debug(PREFIX "transaction end\n");
 267         spin_lock_irqsave(&ec->curr_lock, tmp);
 268         ec->curr = NULL;
 269         spin_unlock_irqrestore(&ec->curr_lock, tmp);
 270         if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
 271                 /* check if we received SCI during transaction */
 272                 ec_check_sci(ec, acpi_ec_read_status(ec));
 273                 /* it is safe to enable GPE outside of transaction */
 274                 acpi_enable_gpe(NULL, ec->gpe);
 275         } else if (t->irq_count > ACPI_EC_STORM_THRESHOLD) {
 276                 pr_info(PREFIX "GPE storm detected, "
 277                         "transactions will use polling mode\n");
 278                 set_bit(EC_FLAGS_GPE_STORM, &ec->flags);
 279         }
 280         return ret;
 281 }
 282
 283 static int ec_check_ibf0(struct acpi_ec *ec)
 284 {
 285         u8 status = acpi_ec_read_status(ec);
 286         return (status & ACPI_EC_FLAG_IBF) == 0;
 287 }
 288
 289 static int ec_wait_ibf0(struct acpi_ec *ec)
 290 {
 291         unsigned long delay = jiffies + msecs_to_jiffies(ACPI_EC_DELAY);
 292         /* interrupt wait manually if GPE mode is not active */
 293         while (time_before(jiffies, delay))
 294                 if (wait_event_timeout(ec->wait, ec_check_ibf0(ec),
 295                                         msecs_to_jiffies(1)))
 296                         return 0;
 297         return -ETIME;
 298 }
 299
 300 static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t)
 301 {
 302         int status;
 303         u32 glk;
 304         if (!ec || (!t) || (t->wlen && !t->wdata) || (t->rlen && !t->rdata))
 305                 return -EINVAL;
 306         if (t->rdata)
 307                 memset(t->rdata, 0, t->rlen);
 308         mutex_lock(&ec->lock);
 309         if (ec->global_lock) {
 310                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
 311                 if (ACPI_FAILURE(status)) {
 312                         status = -ENODEV;
 313                         goto unlock;
 314                 }
 315         }
 316         if (ec_wait_ibf0(ec)) {
 317                 pr_err(PREFIX "input buffer is not empty, "
 318                                 "aborting transaction\n");
 319                 status = -ETIME;
 320                 goto end;
 321         }
 322         status = acpi_ec_transaction_unlocked(ec, t);
 323 end:
 324         if (ec->global_lock)
 325                 acpi_release_global_lock(glk);
 326 unlock:
 327         mutex_unlock(&ec->lock);
 328         return status;
 329 }
 330
 331 static int acpi_ec_burst_enable(struct acpi_ec *ec)
 332 {
 333         u8 d;
 334         struct transaction t = {.command = ACPI_EC_BURST_ENABLE,
 335                                 .wdata = NULL, .rdata = &d,
 336                                 .wlen = 0, .rlen = 1};
 337
 338         return acpi_ec_transaction(ec, &t);
 339 }
 340
 341 static int acpi_ec_burst_disable(struct acpi_ec *ec)
 342 {
 343         struct transaction t = {.command = ACPI_EC_BURST_DISABLE,
 344                                 .wdata = NULL, .rdata = NULL,
 345                                 .wlen = 0, .rlen = 0};
 346
 347         return (acpi_ec_read_status(ec) & ACPI_EC_FLAG_BURST) ?
 348                                 acpi_ec_transaction(ec, &t) : 0;
 349 }
 350
 351 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 * data)
 352 {
 353         int result;
 354         u8 d;
 355         struct transaction t = {.command = ACPI_EC_COMMAND_READ,
 356                                 .wdata = &address, .rdata = &d,
 357                                 .wlen = 1, .rlen = 1};
 358
 359         result = acpi_ec_transaction(ec, &t);
 360         *data = d;
 361         return result;
 362 }
 363
 364 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
 365 {
 366         u8 wdata[2] = { address, data };
 367         struct transaction t = {.command = ACPI_EC_COMMAND_WRITE,
 368                                 .wdata = wdata, .rdata = NULL,
 369                                 .wlen = 2, .rlen = 0};
 370
 371         return acpi_ec_transaction(ec, &t);
 372 }
 373
 374 /*
 375  * Externally callable EC access functions. For now, assume 1 EC only
 376  */
 377 int ec_burst_enable(void)
 378 {
 379         if (!first_ec)
 380                 return -ENODEV;
 381         return acpi_ec_burst_enable(first_ec);
 382 }
 383
 384 EXPORT_SYMBOL(ec_burst_enable);
 385
 386 int ec_burst_disable(void)
 387 {
 388         if (!first_ec)
 389                 return -ENODEV;
 390         return acpi_ec_burst_disable(first_ec);
 391 }
 392
 393 EXPORT_SYMBOL(ec_burst_disable);
 394
 395 int ec_read(u8 addr, u8 * val)
 396 {
 397         int err;
 398         u8 temp_data;
 399
 400         if (!first_ec)
 401                 return -ENODEV;
 402
 403         err = acpi_ec_read(first_ec, addr, &temp_data);
 404
 405         if (!err) {
 406                 *val = temp_data;
 407                 return 0;
 408         } else
 409                 return err;
 410 }
 411
 412 EXPORT_SYMBOL(ec_read);
 413
 414 int ec_write(u8 addr, u8 val)
 415 {
 416         int err;
 417
 418         if (!first_ec)
 419                 return -ENODEV;
 420
 421         err = acpi_ec_write(first_ec, addr, val);
 422
 423         return err;
 424 }
 425
 426 EXPORT_SYMBOL(ec_write);
 427
 428 int ec_transaction(u8 command,
 429                    const u8 * wdata, unsigned wdata_len,
 430                    u8 * rdata, unsigned rdata_len,
 431                    int force_poll)
 432 {
 433         struct transaction t = {.command = command,
 434                                 .wdata = wdata, .rdata = rdata,
 435                                 .wlen = wdata_len, .rlen = rdata_len};
 436         if (!first_ec)
 437                 return -ENODEV;
 438
 439         return acpi_ec_transaction(first_ec, &t);
 440 }
 441
 442 EXPORT_SYMBOL(ec_transaction);
 443
 444 static int acpi_ec_query(struct acpi_ec *ec, u8 * data)
 445 {
 446         int result;
 447         u8 d;
 448         struct transaction t = {.command = ACPI_EC_COMMAND_QUERY,
 449                                 .wdata = NULL, .rdata = &d,
 450                                 .wlen = 0, .rlen = 1};
 451         if (!ec || !data)
 452                 return -EINVAL;
 453
 454         /*
 455          * Query the EC to find out which _Qxx method we need to evaluate.
 456          * Note that successful completion of the query causes the ACPI_EC_SCI
 457          * bit to be cleared (and thus clearing the interrupt source).
 458          */
 459
 460         result = acpi_ec_transaction(ec, &t);
 461         if (result)
 462                 return result;
 463
 464         if (!d)
 465                 return -ENODATA;
 466
 467         *data = d;
 468         return 0;
 469 }
 470
 471 /* --------------------------------------------------------------------------
 472                                 Event Management
 473    -------------------------------------------------------------------------- */
 474 int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
 475                               acpi_handle handle, acpi_ec_query_func func,
 476                               void *data)
 477 {
 478         struct acpi_ec_query_handler *handler =
 479             kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL);
 480         if (!handler)
 481                 return -ENOMEM;
 482
 483         handler->query_bit = query_bit;
 484         handler->handle = handle;
 485         handler->func = func;
 486         handler->data = data;
 487         mutex_lock(&ec->lock);
 488         list_add(&handler->node, &ec->list);
 489         mutex_unlock(&ec->lock);
 490         return 0;
 491 }
 492
 493 EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler);
 494
 495 void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit)
 496 {
 497         struct acpi_ec_query_handler *handler, *tmp;
 498         mutex_lock(&ec->lock);
 499         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
 500                 if (query_bit == handler->query_bit) {
 501                         list_del(&handler->node);
 502                         kfree(handler);
 503                 }
 504         }
 505         mutex_unlock(&ec->lock);
 506 }
 507
 508 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler);
 509
 510 static void acpi_ec_gpe_query(void *ec_cxt)
 511 {
 512         struct acpi_ec *ec = ec_cxt;
 513         u8 value = 0;
 514         struct acpi_ec_query_handler *handler, copy;
 515
 516         if (!ec || acpi_ec_query(ec, &value))
 517                 return;
 518         mutex_lock(&ec->lock);
 519         list_for_each_entry(handler, &ec->list, node) {
 520                 if (value == handler->query_bit) {
 521                         /* have custom handler for this bit */
 522                         memcpy(&copy, handler, sizeof(copy));
 523                         mutex_unlock(&ec->lock);
 524                         if (copy.func) {
 525                                 copy.func(copy.data);
 526                         } else if (copy.handle) {
 527                                 acpi_evaluate_object(copy.handle, NULL, NULL, NULL);
 528                         }
 529                         return;
 530                 }
 531         }
 532         mutex_unlock(&ec->lock);
 533 }
 534
 535 static u32 acpi_ec_gpe_handler(void *data)
 536 {
 537         struct acpi_ec *ec = data;
 538         u8 status;
 539
 540         pr_debug(PREFIX "~~~> interrupt\n");
 541         status = acpi_ec_read_status(ec);
 542
 543         advance_transaction(ec, status);
 544         if (ec_transaction_done(ec) && (status & ACPI_EC_FLAG_IBF) == 0)
 545                 wake_up(&ec->wait);
 546         ec_check_sci(ec, status);
 547         return ACPI_INTERRUPT_HANDLED;
 548 }
 549
 550 /* --------------------------------------------------------------------------
 551                              Address Space Management
 552    -------------------------------------------------------------------------- */
 553
 554 static acpi_status
 555 acpi_ec_space_handler(u32 function, acpi_physical_address address,
 556                       u32 bits, acpi_integer *value,
 557                       void *handler_context, void *region_context)
 558 {
 559         struct acpi_ec *ec = handler_context;
 560         int result = 0, i;
 561         u8 temp = 0;
 562
 563         if ((address > 0xFF) || !value || !handler_context)
 564                 return AE_BAD_PARAMETER;
 565
 566         if (function != ACPI_READ && function != ACPI_WRITE)
 567                 return AE_BAD_PARAMETER;
 568
 569         if (bits != 8 && acpi_strict)
 570                 return AE_BAD_PARAMETER;
 571
 572         if (EC_FLAGS_MSI)
 573                 acpi_ec_burst_enable(ec);
 574
 575         if (function == ACPI_READ) {
 576                 result = acpi_ec_read(ec, address, &temp);
 577                 *value = temp;
 578         } else {
 579                 temp = 0xff & (*value);
 580                 result = acpi_ec_write(ec, address, temp);
 581         }
 582
 583         for (i = 8; unlikely(bits - i > 0); i += 8) {
 584                 ++address;
 585                 if (function == ACPI_READ) {
 586                         result = acpi_ec_read(ec, address, &temp);
 587                         (*value) |= ((acpi_integer)temp) << i;
 588                 } else {
 589                         temp = 0xff & ((*value) >> i);
 590                         result = acpi_ec_write(ec, address, temp);
 591                 }
 592         }
 593
 594         if (EC_FLAGS_MSI)
 595                 acpi_ec_burst_disable(ec);
 596
 597         switch (result) {
 598         case -EINVAL:
 599                 return AE_BAD_PARAMETER;
 600                 break;
 601         case -ENODEV:
 602                 return AE_NOT_FOUND;
 603                 break;
 604         case -ETIME:
 605                 return AE_TIME;
 606                 break;
 607         default:
 608                 return AE_OK;
 609         }
 610 }
 611
 612 /* --------------------------------------------------------------------------
 613                               FS Interface (/proc)
 614    -------------------------------------------------------------------------- */
 615
 616 static struct proc_dir_entry *acpi_ec_dir;
 617
 618 static int acpi_ec_read_info(struct seq_file *seq, void *offset)
 619 {
 620         struct acpi_ec *ec = seq->private;
 621
 622         if (!ec)
 623                 goto end;
 624
 625         seq_printf(seq, "gpe:\t\t\t0x%02x\n", (u32) ec->gpe);
 626         seq_printf(seq, "ports:\t\t\t0x%02x, 0x%02x\n",
 627                    (unsigned)ec->command_addr, (unsigned)ec->data_addr);
 628         seq_printf(seq, "use global lock:\t%s\n",
 629                    ec->global_lock ? "yes" : "no");
 630       end:
 631         return 0;
 632 }
 633
 634 static int acpi_ec_info_open_fs(struct inode *inode, struct file *file)
 635 {
 636         return single_open(file, acpi_ec_read_info, PDE(inode)->data);
 637 }
 638
 639 static const struct file_operations acpi_ec_info_ops = {
 640         .open = acpi_ec_info_open_fs,
 641         .read = seq_read,
 642         .llseek = seq_lseek,
 643         .release = single_release,
 644         .owner = THIS_MODULE,
 645 };
 646
 647 static int acpi_ec_add_fs(struct acpi_device *device)
 648 {
 649         struct proc_dir_entry *entry = NULL;
 650
 651         if (!acpi_device_dir(device)) {
 652                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
 653                                                      acpi_ec_dir);
 654                 if (!acpi_device_dir(device))
 655                         return -ENODEV;
 656         }
 657
 658         entry = proc_create_data(ACPI_EC_FILE_INFO, S_IRUGO,
 659                                  acpi_device_dir(device),
 660                                  &acpi_ec_info_ops, acpi_driver_data(device));
 661         if (!entry)
 662                 return -ENODEV;
 663         return 0;
 664 }
 665
 666 static int acpi_ec_remove_fs(struct acpi_device *device)
 667 {
 668
 669         if (acpi_device_dir(device)) {
 670                 remove_proc_entry(ACPI_EC_FILE_INFO, acpi_device_dir(device));
 671                 remove_proc_entry(acpi_device_bid(device), acpi_ec_dir);
 672                 acpi_device_dir(device) = NULL;
 673         }
 674
 675         return 0;
 676 }
 677
 678 /* --------------------------------------------------------------------------
 679                                Driver Interface
 680    -------------------------------------------------------------------------- */
 681 static acpi_status
 682 ec_parse_io_ports(struct acpi_resource *resource, void *context);
 683
 684 static struct acpi_ec *make_acpi_ec(void)
 685 {
 686         struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
 687         if (!ec)
 688                 return NULL;
 689         ec->flags = 1 << EC_FLAGS_QUERY_PENDING;
 690         mutex_init(&ec->lock);
 691         init_waitqueue_head(&ec->wait);
 692         INIT_LIST_HEAD(&ec->list);
 693         spin_lock_init(&ec->curr_lock);
 694         return ec;
 695 }
 696
 697 static acpi_status
 698 acpi_ec_register_query_methods(acpi_handle handle, u32 level,
 699                                void *context, void **return_value)
 700 {
 701         char node_name[5];
 702         struct acpi_buffer buffer = { sizeof(node_name), node_name };
 703         struct acpi_ec *ec = context;
 704         int value = 0;
 705         acpi_status status;
 706
 707         status = acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
 708
 709         if (ACPI_SUCCESS(status) && sscanf(node_name, "_Q%x", &value) == 1) {
 710                 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL);
 711         }
 712         return AE_OK;
 713 }
 714
 715 static acpi_status
 716 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
 717 {
 718         acpi_status status;
 719         unsigned long long tmp = 0;
 720
 721         struct acpi_ec *ec = context;
 722
 723         /* clear addr values, ec_parse_io_ports depend on it */
 724         ec->command_addr = ec->data_addr = 0;
 725
 726         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
 727                                      ec_parse_io_ports, ec);
 728         if (ACPI_FAILURE(status))
 729                 return status;
 730
 731         /* Get GPE bit assignment (EC events). */
 732         /* TODO: Add support for _GPE returning a package */
 733         status = acpi_evaluate_integer(handle, "_GPE", NULL, &tmp);
 734         if (ACPI_FAILURE(status))
 735                 return status;
 736         ec->gpe = tmp;
 737         /* Use the global lock for all EC transactions? */
 738         tmp = 0;
 739         acpi_evaluate_integer(handle, "_GLK", NULL, &tmp);
 740         ec->global_lock = tmp;
 741         ec->handle = handle;
 742         return AE_CTRL_TERMINATE;
 743 }
 744
 745 static int ec_install_handlers(struct acpi_ec *ec)
 746 {
 747         acpi_status status;
 748         if (test_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags))
 749                 return 0;
 750         status = acpi_install_gpe_handler(NULL, ec->gpe,
 751                                   ACPI_GPE_EDGE_TRIGGERED,
 752                                   &acpi_ec_gpe_handler, ec);
 753         if (ACPI_FAILURE(status))
 754                 return -ENODEV;
 755         acpi_set_gpe_type(NULL, ec->gpe, ACPI_GPE_TYPE_RUNTIME);
 756         acpi_enable_gpe(NULL, ec->gpe);
 757         status = acpi_install_address_space_handler(ec->handle,
 758                                                     ACPI_ADR_SPACE_EC,
 759                                                     &acpi_ec_space_handler,
 760                                                     NULL, ec);
 761         if (ACPI_FAILURE(status)) {
 762                 if (status == AE_NOT_FOUND) {
 763                         /*
 764                          * Maybe OS fails in evaluating the _REG object.
 765                          * The AE_NOT_FOUND error will be ignored and OS
 766                          * continue to initialize EC.
 767                          */
 768                         printk(KERN_ERR "Fail in evaluating the _REG object"
 769                                 " of EC device. Broken bios is suspected.\n");
 770                 } else {
 771                         acpi_remove_gpe_handler(NULL, ec->gpe,
 772                                 &acpi_ec_gpe_handler);
 773                         return -ENODEV;
 774                 }
 775         }
 776
 777         set_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
 778         return 0;
 779 }
 780
 781 static void ec_remove_handlers(struct acpi_ec *ec)
 782 {
 783         if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle,
 784                                 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler)))
 785                 pr_err(PREFIX "failed to remove space handler\n");
 786         if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe,
 787                                 &acpi_ec_gpe_handler)))
 788                 pr_err(PREFIX "failed to remove gpe handler\n");
 789         clear_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
 790 }
 791
 792 static int acpi_ec_add(struct acpi_device *device)
 793 {
 794         struct acpi_ec *ec = NULL;
 795         int ret;
 796
 797         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
 798         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
 799
 800         /* Check for boot EC */
 801         if (boot_ec &&
 802             (boot_ec->handle == device->handle ||
 803              boot_ec->handle == ACPI_ROOT_OBJECT)) {
 804                 ec = boot_ec;
 805                 boot_ec = NULL;
 806         } else {
 807                 ec = make_acpi_ec();
 808                 if (!ec)
 809                         return -ENOMEM;
 810         }
 811         if (ec_parse_device(device->handle, 0, ec, NULL) !=
 812                 AE_CTRL_TERMINATE) {
 813                         kfree(ec);
 814                         return -EINVAL;
 815         }
 816
 817         ec->handle = device->handle;
 818
 819         /* Find and register all query methods */
 820         acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1,
 821                             acpi_ec_register_query_methods, ec, NULL);
 822
 823         if (!first_ec)
 824                 first_ec = ec;
 825         device->driver_data = ec;
 826         acpi_ec_add_fs(device);
 827         pr_info(PREFIX "GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n",
 828                           ec->gpe, ec->command_addr, ec->data_addr);
 829
 830         ret = ec_install_handlers(ec);
 831
 832         /* EC is fully operational, allow queries */
 833         clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
 834         return ret;
 835 }
 836
 837 static int acpi_ec_remove(struct acpi_device *device, int type)
 838 {
 839         struct acpi_ec *ec;
 840         struct acpi_ec_query_handler *handler, *tmp;
 841
 842         if (!device)
 843                 return -EINVAL;
 844
 845         ec = acpi_driver_data(device);
 846         ec_remove_handlers(ec);
 847         mutex_lock(&ec->lock);
 848         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
 849                 list_del(&handler->node);
 850                 kfree(handler);
 851         }
 852         mutex_unlock(&ec->lock);
 853         acpi_ec_remove_fs(device);
 854         device->driver_data = NULL;
 855         if (ec == first_ec)
 856                 first_ec = NULL;
 857         kfree(ec);
 858         return 0;
 859 }
 860
 861 static acpi_status
 862 ec_parse_io_ports(struct acpi_resource *resource, void *context)
 863 {
 864         struct acpi_ec *ec = context;
 865
 866         if (resource->type != ACPI_RESOURCE_TYPE_IO)
 867                 return AE_OK;
 868
 869         /*
 870          * The first address region returned is the data port, and
 871          * the second address region returned is the status/command
 872          * port.
 873          */
 874         if (ec->data_addr == 0)
 875                 ec->data_addr = resource->data.io.minimum;
 876         else if (ec->command_addr == 0)
 877                 ec->command_addr = resource->data.io.minimum;
 878         else
 879                 return AE_CTRL_TERMINATE;
 880
 881         return AE_OK;
 882 }
 883
 884 int __init acpi_boot_ec_enable(void)
 885 {
 886         if (!boot_ec || test_bit(EC_FLAGS_HANDLERS_INSTALLED, &boot_ec->flags))
 887                 return 0;
 888         if (!ec_install_handlers(boot_ec)) {
 889                 first_ec = boot_ec;
 890                 return 0;
 891         }
 892         return -EFAULT;
 893 }
 894
 895 static const struct acpi_device_id ec_device_ids[] = {
 896         {"PNP0C09", 0},
 897         {"", 0},
 898 };
 899
 900 int __init acpi_ec_ecdt_probe(void)
 901 {
 902         acpi_status status;
 903         struct acpi_ec *saved_ec = NULL;
 904         struct acpi_table_ecdt *ecdt_ptr;
 905
 906         boot_ec = make_acpi_ec();
 907         if (!boot_ec)
 908                 return -ENOMEM;
 909         /*
 910          * Generate a boot ec context
 911          */
 912         if (dmi_name_in_vendors("Micro-Star") ||
 913             dmi_name_in_vendors("Notebook")) {
 914                 pr_info(PREFIX "Enabling special treatment for EC from MSI.\n");
 915                 EC_FLAGS_MSI = 1;
 916         }
 917         status = acpi_get_table(ACPI_SIG_ECDT, 1,
 918                                 (struct acpi_table_header **)&ecdt_ptr);
 919         if (ACPI_SUCCESS(status)) {
 920                 pr_info(PREFIX "EC description table is found, configuring boot EC\n");
 921                 boot_ec->command_addr = ecdt_ptr->control.address;
 922                 boot_ec->data_addr = ecdt_ptr->data.address;
 923                 boot_ec->gpe = ecdt_ptr->gpe;
 924                 boot_ec->handle = ACPI_ROOT_OBJECT;
 925                 acpi_get_handle(ACPI_ROOT_OBJECT, ecdt_ptr->id, &boot_ec->handle);
 926                 /* Don't trust ECDT, which comes from ASUSTek */
 927                 if (!dmi_name_in_vendors("ASUS") && EC_FLAGS_MSI == 0)
 928                         goto install;
 929                 saved_ec = kmalloc(sizeof(struct acpi_ec), GFP_KERNEL);
 930                 if (!saved_ec)
 931                         return -ENOMEM;
 932                 memcpy(saved_ec, boot_ec, sizeof(struct acpi_ec));
 933         /* fall through */
 934         }
 935         /* This workaround is needed only on some broken machines,
 936          * which require early EC, but fail to provide ECDT */
 937         printk(KERN_DEBUG PREFIX "Look up EC in DSDT\n");
 938         status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device,
 939                                         boot_ec, NULL);
 940         /* Check that acpi_get_devices actually find something */
 941         if (ACPI_FAILURE(status) || !boot_ec->handle)
 942                 goto error;
 943         if (saved_ec) {
 944                 /* try to find good ECDT from ASUSTek */
 945                 if (saved_ec->command_addr != boot_ec->command_addr ||
 946                     saved_ec->data_addr != boot_ec->data_addr ||
 947                     saved_ec->gpe != boot_ec->gpe ||
 948                     saved_ec->handle != boot_ec->handle)
 949                         pr_info(PREFIX "ASUSTek keeps feeding us with broken "
 950                         "ECDT tables, which are very hard to workaround. "
 951                         "Trying to use DSDT EC info instead. Please send "
 952                         "output of acpidump to linux-acpi@vger.kernel.org\n");
 953                 kfree(saved_ec);
 954                 saved_ec = NULL;
 955         } else {
 956                 /* We really need to limit this workaround, the only ASUS,
 957                 * which needs it, has fake EC._INI method, so use it as flag.
 958                 * Keep boot_ec struct as it will be needed soon.
 959                 */
 960                 acpi_handle dummy;
 961                 if (!dmi_name_in_vendors("ASUS") ||
 962                     ACPI_FAILURE(acpi_get_handle(boot_ec->handle, "_INI",
 963                                                         &dummy)))
 964                         return -ENODEV;
 965         }
 966 install:
 967         if (!ec_install_handlers(boot_ec)) {
 968                 first_ec = boot_ec;
 969                 return 0;
 970         }
 971 error:
 972         kfree(boot_ec);
 973         boot_ec = NULL;
 974         return -ENODEV;
 975 }
 976
 977 static int acpi_ec_suspend(struct acpi_device *device, pm_message_t state)
 978 {
 979         struct acpi_ec *ec = acpi_driver_data(device);
 980         /* Stop using GPE */
 981         acpi_disable_gpe(NULL, ec->gpe);
 982         return 0;
 983 }
 984
 985 static int acpi_ec_resume(struct acpi_device *device)
 986 {
 987         struct acpi_ec *ec = acpi_driver_data(device);
 988         /* Enable use of GPE back */
 989         acpi_enable_gpe(NULL, ec->gpe);
 990         return 0;
 991 }
 992
 993 static struct acpi_driver acpi_ec_driver = {
 994         .name = "ec",
 995         .class = ACPI_EC_CLASS,
 996         .ids = ec_device_ids,
 997         .ops = {
 998                 .add = acpi_ec_add,
 999                 .remove = acpi_ec_remove,
1000                 .suspend = acpi_ec_suspend,
1001                 .resume = acpi_ec_resume,
1002                 },
1003 };
1004
1005 int __init acpi_ec_init(void)
1006 {
1007         int result = 0;
1008
1009         acpi_ec_dir = proc_mkdir(ACPI_EC_CLASS, acpi_root_dir);
1010         if (!acpi_ec_dir)
1011                 return -ENODEV;
1012
1013         /* Now register the driver for the EC */
1014         result = acpi_bus_register_driver(&acpi_ec_driver);
1015         if (result < 0) {
1016                 remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1017                 return -ENODEV;
1018         }
1019
1020         return result;
1021 }
1022
1023 /* EC driver currently not unloadable */
1024 #if 0
1025 static void __exit acpi_ec_exit(void)
1026 {
1027
1028         acpi_bus_unregister_driver(&acpi_ec_driver);
1029
1030         remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1031
1032         return;
1033 }
1034 #endif  /* 0 */