1 /* 2 * ec.c - ACPI Embedded Controller Driver (v3) 3 * 4 * Copyright (C) 2001-2015 Intel Corporation 5 * Author: 2014, 2015 Lv Zheng <lv.zheng@intel.com> 6 * 2006, 2007 Alexey Starikovskiy <alexey.y.starikovskiy@intel.com> 7 * 2006 Denis Sadykov <denis.m.sadykov@intel.com> 8 * 2004 Luming Yu <luming.yu@intel.com> 9 * 2001, 2002 Andy Grover <andrew.grover@intel.com> 10 * 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com> 11 * Copyright (C) 2008 Alexey Starikovskiy <astarikovskiy@suse.de> 12 * 13 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 14 * 15 * This program is free software; you can redistribute it and/or modify 16 * it under the terms of the GNU General Public License as published by 17 * the Free Software Foundation; either version 2 of the License, or (at 18 * your option) any later version. 19 * 20 * This program is distributed in the hope that it will be useful, but 21 * WITHOUT ANY WARRANTY; without even the implied warranty of 22 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 23 * General Public License for more details. 24 * 25 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 26 */ 27 28 /* Uncomment next line to get verbose printout */ 29 /* #define DEBUG */ 30 #define pr_fmt(fmt) "ACPI : EC: " fmt 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/interrupt.h> 38 #include <linux/list.h> 39 #include <linux/spinlock.h> 40 #include <linux/slab.h> 41 #include <linux/acpi.h> 42 #include <linux/dmi.h> 43 #include <asm/io.h> 44 45 #include "internal.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 /* EC status register */ 52 #define ACPI_EC_FLAG_OBF 0x01 /* Output buffer full */ 53 #define ACPI_EC_FLAG_IBF 0x02 /* Input buffer full */ 54 #define ACPI_EC_FLAG_CMD 0x08 /* Input buffer contains a command */ 55 #define ACPI_EC_FLAG_BURST 0x10 /* burst mode */ 56 #define ACPI_EC_FLAG_SCI 0x20 /* EC-SCI occurred */ 57 58 /* 59 * The SCI_EVT clearing timing is not defined by the ACPI specification. 60 * This leads to lots of practical timing issues for the host EC driver. 61 * The following variations are defined (from the target EC firmware's 62 * perspective): 63 * STATUS: After indicating SCI_EVT edge triggered IRQ to the host, the 64 * target can clear SCI_EVT at any time so long as the host can see 65 * the indication by reading the status register (EC_SC). So the 66 * host should re-check SCI_EVT after the first time the SCI_EVT 67 * indication is seen, which is the same time the query request 68 * (QR_EC) is written to the command register (EC_CMD). SCI_EVT set 69 * at any later time could indicate another event. Normally such 70 * kind of EC firmware has implemented an event queue and will 71 * return 0x00 to indicate "no outstanding event". 72 * QUERY: After seeing the query request (QR_EC) written to the command 73 * register (EC_CMD) by the host and having prepared the responding 74 * event value in the data register (EC_DATA), the target can safely 75 * clear SCI_EVT because the target can confirm that the current 76 * event is being handled by the host. The host then should check 77 * SCI_EVT right after reading the event response from the data 78 * register (EC_DATA). 79 * EVENT: After seeing the event response read from the data register 80 * (EC_DATA) by the host, the target can clear SCI_EVT. As the 81 * target requires time to notice the change in the data register 82 * (EC_DATA), the host may be required to wait additional guarding 83 * time before checking the SCI_EVT again. Such guarding may not be 84 * necessary if the host is notified via another IRQ. 85 */ 86 #define ACPI_EC_EVT_TIMING_STATUS 0x00 87 #define ACPI_EC_EVT_TIMING_QUERY 0x01 88 #define ACPI_EC_EVT_TIMING_EVENT 0x02 89 90 /* EC commands */ 91 enum ec_command { 92 ACPI_EC_COMMAND_READ = 0x80, 93 ACPI_EC_COMMAND_WRITE = 0x81, 94 ACPI_EC_BURST_ENABLE = 0x82, 95 ACPI_EC_BURST_DISABLE = 0x83, 96 ACPI_EC_COMMAND_QUERY = 0x84, 97 }; 98 99 #define ACPI_EC_DELAY 500 /* Wait 500ms max. during EC ops */ 100 #define ACPI_EC_UDELAY_GLK 1000 /* Wait 1ms max. to get global lock */ 101 #define ACPI_EC_UDELAY_POLL 550 /* Wait 1ms for EC transaction polling */ 102 #define ACPI_EC_CLEAR_MAX 100 /* Maximum number of events to query 103 * when trying to clear the EC */ 104 105 enum { 106 EC_FLAGS_QUERY_PENDING, /* Query is pending */ 107 EC_FLAGS_QUERY_GUARDING, /* Guard for SCI_EVT check */ 108 EC_FLAGS_HANDLERS_INSTALLED, /* Handlers for GPE and 109 * OpReg are installed */ 110 EC_FLAGS_STARTED, /* Driver is started */ 111 EC_FLAGS_STOPPED, /* Driver is stopped */ 112 EC_FLAGS_COMMAND_STORM, /* GPE storms occurred to the 113 * current command processing */ 114 }; 115 116 #define ACPI_EC_COMMAND_POLL 0x01 /* Available for command byte */ 117 #define ACPI_EC_COMMAND_COMPLETE 0x02 /* Completed last byte */ 118 119 /* ec.c is compiled in acpi namespace so this shows up as acpi.ec_delay param */ 120 static unsigned int ec_delay __read_mostly = ACPI_EC_DELAY; 121 module_param(ec_delay, uint, 0644); 122 MODULE_PARM_DESC(ec_delay, "Timeout(ms) waited until an EC command completes"); 123 124 static bool ec_busy_polling __read_mostly; 125 module_param(ec_busy_polling, bool, 0644); 126 MODULE_PARM_DESC(ec_busy_polling, "Use busy polling to advance EC transaction"); 127 128 static unsigned int ec_polling_guard __read_mostly = ACPI_EC_UDELAY_POLL; 129 module_param(ec_polling_guard, uint, 0644); 130 MODULE_PARM_DESC(ec_polling_guard, "Guard time(us) between EC accesses in polling modes"); 131 132 static unsigned int ec_event_clearing __read_mostly = ACPI_EC_EVT_TIMING_QUERY; 133 134 /* 135 * If the number of false interrupts per one transaction exceeds 136 * this threshold, will think there is a GPE storm happened and 137 * will disable the GPE for normal transaction. 138 */ 139 static unsigned int ec_storm_threshold __read_mostly = 8; 140 module_param(ec_storm_threshold, uint, 0644); 141 MODULE_PARM_DESC(ec_storm_threshold, "Maxim false GPE numbers not considered as GPE storm"); 142 143 struct acpi_ec_query_handler { 144 struct list_head node; 145 acpi_ec_query_func func; 146 acpi_handle handle; 147 void *data; 148 u8 query_bit; 149 struct kref kref; 150 }; 151 152 struct transaction { 153 const u8 *wdata; 154 u8 *rdata; 155 unsigned short irq_count; 156 u8 command; 157 u8 wi; 158 u8 ri; 159 u8 wlen; 160 u8 rlen; 161 u8 flags; 162 }; 163 164 struct acpi_ec_query { 165 struct transaction transaction; 166 struct work_struct work; 167 struct acpi_ec_query_handler *handler; 168 }; 169 170 static int acpi_ec_query(struct acpi_ec *ec, u8 *data); 171 static void advance_transaction(struct acpi_ec *ec); 172 static void acpi_ec_event_handler(struct work_struct *work); 173 static void acpi_ec_event_processor(struct work_struct *work); 174 175 struct acpi_ec *boot_ec, *first_ec; 176 EXPORT_SYMBOL(first_ec); 177 178 static int EC_FLAGS_VALIDATE_ECDT; /* ASUStec ECDTs need to be validated */ 179 static int EC_FLAGS_SKIP_DSDT_SCAN; /* Not all BIOS survive early DSDT scan */ 180 static int EC_FLAGS_CLEAR_ON_RESUME; /* Needs acpi_ec_clear() on boot/resume */ 181 static int EC_FLAGS_QUERY_HANDSHAKE; /* Needs QR_EC issued when SCI_EVT set */ 182 183 /* -------------------------------------------------------------------------- 184 * Logging/Debugging 185 * -------------------------------------------------------------------------- */ 186 187 /* 188 * Splitters used by the developers to track the boundary of the EC 189 * handling processes. 190 */ 191 #ifdef DEBUG 192 #define EC_DBG_SEP " " 193 #define EC_DBG_DRV "+++++" 194 #define EC_DBG_STM "=====" 195 #define EC_DBG_REQ "*****" 196 #define EC_DBG_EVT "#####" 197 #else 198 #define EC_DBG_SEP "" 199 #define EC_DBG_DRV 200 #define EC_DBG_STM 201 #define EC_DBG_REQ 202 #define EC_DBG_EVT 203 #endif 204 205 #define ec_log_raw(fmt, ...) \ 206 pr_info(fmt "\n", ##__VA_ARGS__) 207 #define ec_dbg_raw(fmt, ...) \ 208 pr_debug(fmt "\n", ##__VA_ARGS__) 209 #define ec_log(filter, fmt, ...) \ 210 ec_log_raw(filter EC_DBG_SEP fmt EC_DBG_SEP filter, ##__VA_ARGS__) 211 #define ec_dbg(filter, fmt, ...) \ 212 ec_dbg_raw(filter EC_DBG_SEP fmt EC_DBG_SEP filter, ##__VA_ARGS__) 213 214 #define ec_log_drv(fmt, ...) \ 215 ec_log(EC_DBG_DRV, fmt, ##__VA_ARGS__) 216 #define ec_dbg_drv(fmt, ...) \ 217 ec_dbg(EC_DBG_DRV, fmt, ##__VA_ARGS__) 218 #define ec_dbg_stm(fmt, ...) \ 219 ec_dbg(EC_DBG_STM, fmt, ##__VA_ARGS__) 220 #define ec_dbg_req(fmt, ...) \ 221 ec_dbg(EC_DBG_REQ, fmt, ##__VA_ARGS__) 222 #define ec_dbg_evt(fmt, ...) \ 223 ec_dbg(EC_DBG_EVT, fmt, ##__VA_ARGS__) 224 #define ec_dbg_ref(ec, fmt, ...) \ 225 ec_dbg_raw("%lu: " fmt, ec->reference_count, ## __VA_ARGS__) 226 227 /* -------------------------------------------------------------------------- 228 * Device Flags 229 * -------------------------------------------------------------------------- */ 230 231 static bool acpi_ec_started(struct acpi_ec *ec) 232 { 233 return test_bit(EC_FLAGS_STARTED, &ec->flags) && 234 !test_bit(EC_FLAGS_STOPPED, &ec->flags); 235 } 236 237 static bool acpi_ec_flushed(struct acpi_ec *ec) 238 { 239 return ec->reference_count == 1; 240 } 241 242 /* -------------------------------------------------------------------------- 243 * EC Registers 244 * -------------------------------------------------------------------------- */ 245 246 static inline u8 acpi_ec_read_status(struct acpi_ec *ec) 247 { 248 u8 x = inb(ec->command_addr); 249 250 ec_dbg_raw("EC_SC(R) = 0x%2.2x " 251 "SCI_EVT=%d BURST=%d CMD=%d IBF=%d OBF=%d", 252 x, 253 !!(x & ACPI_EC_FLAG_SCI), 254 !!(x & ACPI_EC_FLAG_BURST), 255 !!(x & ACPI_EC_FLAG_CMD), 256 !!(x & ACPI_EC_FLAG_IBF), 257 !!(x & ACPI_EC_FLAG_OBF)); 258 return x; 259 } 260 261 static inline u8 acpi_ec_read_data(struct acpi_ec *ec) 262 { 263 u8 x = inb(ec->data_addr); 264 265 ec->timestamp = jiffies; 266 ec_dbg_raw("EC_DATA(R) = 0x%2.2x", x); 267 return x; 268 } 269 270 static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command) 271 { 272 ec_dbg_raw("EC_SC(W) = 0x%2.2x", command); 273 outb(command, ec->command_addr); 274 ec->timestamp = jiffies; 275 } 276 277 static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data) 278 { 279 ec_dbg_raw("EC_DATA(W) = 0x%2.2x", data); 280 outb(data, ec->data_addr); 281 ec->timestamp = jiffies; 282 } 283 284 #ifdef DEBUG 285 static const char *acpi_ec_cmd_string(u8 cmd) 286 { 287 switch (cmd) { 288 case 0x80: 289 return "RD_EC"; 290 case 0x81: 291 return "WR_EC"; 292 case 0x82: 293 return "BE_EC"; 294 case 0x83: 295 return "BD_EC"; 296 case 0x84: 297 return "QR_EC"; 298 } 299 return "UNKNOWN"; 300 } 301 #else 302 #define acpi_ec_cmd_string(cmd) "UNDEF" 303 #endif 304 305 /* -------------------------------------------------------------------------- 306 * GPE Registers 307 * -------------------------------------------------------------------------- */ 308 309 static inline bool acpi_ec_is_gpe_raised(struct acpi_ec *ec) 310 { 311 acpi_event_status gpe_status = 0; 312 313 (void)acpi_get_gpe_status(NULL, ec->gpe, &gpe_status); 314 return (gpe_status & ACPI_EVENT_FLAG_STATUS_SET) ? true : false; 315 } 316 317 static inline void acpi_ec_enable_gpe(struct acpi_ec *ec, bool open) 318 { 319 if (open) 320 acpi_enable_gpe(NULL, ec->gpe); 321 else { 322 BUG_ON(ec->reference_count < 1); 323 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_ENABLE); 324 } 325 if (acpi_ec_is_gpe_raised(ec)) { 326 /* 327 * On some platforms, EN=1 writes cannot trigger GPE. So 328 * software need to manually trigger a pseudo GPE event on 329 * EN=1 writes. 330 */ 331 ec_dbg_raw("Polling quirk"); 332 advance_transaction(ec); 333 } 334 } 335 336 static inline void acpi_ec_disable_gpe(struct acpi_ec *ec, bool close) 337 { 338 if (close) 339 acpi_disable_gpe(NULL, ec->gpe); 340 else { 341 BUG_ON(ec->reference_count < 1); 342 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_DISABLE); 343 } 344 } 345 346 static inline void acpi_ec_clear_gpe(struct acpi_ec *ec) 347 { 348 /* 349 * GPE STS is a W1C register, which means: 350 * 1. Software can clear it without worrying about clearing other 351 * GPEs' STS bits when the hardware sets them in parallel. 352 * 2. As long as software can ensure only clearing it when it is 353 * set, hardware won't set it in parallel. 354 * So software can clear GPE in any contexts. 355 * Warning: do not move the check into advance_transaction() as the 356 * EC commands will be sent without GPE raised. 357 */ 358 if (!acpi_ec_is_gpe_raised(ec)) 359 return; 360 acpi_clear_gpe(NULL, ec->gpe); 361 } 362 363 /* -------------------------------------------------------------------------- 364 * Transaction Management 365 * -------------------------------------------------------------------------- */ 366 367 static void acpi_ec_submit_request(struct acpi_ec *ec) 368 { 369 ec->reference_count++; 370 if (ec->reference_count == 1) 371 acpi_ec_enable_gpe(ec, true); 372 } 373 374 static void acpi_ec_complete_request(struct acpi_ec *ec) 375 { 376 bool flushed = false; 377 378 ec->reference_count--; 379 if (ec->reference_count == 0) 380 acpi_ec_disable_gpe(ec, true); 381 flushed = acpi_ec_flushed(ec); 382 if (flushed) 383 wake_up(&ec->wait); 384 } 385 386 static void acpi_ec_set_storm(struct acpi_ec *ec, u8 flag) 387 { 388 if (!test_bit(flag, &ec->flags)) { 389 acpi_ec_disable_gpe(ec, false); 390 ec_dbg_drv("Polling enabled"); 391 set_bit(flag, &ec->flags); 392 } 393 } 394 395 static void acpi_ec_clear_storm(struct acpi_ec *ec, u8 flag) 396 { 397 if (test_bit(flag, &ec->flags)) { 398 clear_bit(flag, &ec->flags); 399 acpi_ec_enable_gpe(ec, false); 400 ec_dbg_drv("Polling disabled"); 401 } 402 } 403 404 /* 405 * acpi_ec_submit_flushable_request() - Increase the reference count unless 406 * the flush operation is not in 407 * progress 408 * @ec: the EC device 409 * 410 * This function must be used before taking a new action that should hold 411 * the reference count. If this function returns false, then the action 412 * must be discarded or it will prevent the flush operation from being 413 * completed. 414 */ 415 static bool acpi_ec_submit_flushable_request(struct acpi_ec *ec) 416 { 417 if (!acpi_ec_started(ec)) 418 return false; 419 acpi_ec_submit_request(ec); 420 return true; 421 } 422 423 static void acpi_ec_submit_query(struct acpi_ec *ec) 424 { 425 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) { 426 ec_dbg_evt("Command(%s) submitted/blocked", 427 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY)); 428 ec->nr_pending_queries++; 429 schedule_work(&ec->work); 430 } 431 } 432 433 static void acpi_ec_complete_query(struct acpi_ec *ec) 434 { 435 if (test_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) { 436 clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags); 437 ec_dbg_evt("Command(%s) unblocked", 438 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY)); 439 } 440 } 441 442 static bool acpi_ec_guard_event(struct acpi_ec *ec) 443 { 444 bool guarded = true; 445 unsigned long flags; 446 447 spin_lock_irqsave(&ec->lock, flags); 448 /* 449 * If firmware SCI_EVT clearing timing is "event", we actually 450 * don't know when the SCI_EVT will be cleared by firmware after 451 * evaluating _Qxx, so we need to re-check SCI_EVT after waiting an 452 * acceptable period. 453 * 454 * The guarding period begins when EC_FLAGS_QUERY_PENDING is 455 * flagged, which means SCI_EVT check has just been performed. 456 * But if the current transaction is ACPI_EC_COMMAND_QUERY, the 457 * guarding should have already been performed (via 458 * EC_FLAGS_QUERY_GUARDING) and should not be applied so that the 459 * ACPI_EC_COMMAND_QUERY transaction can be transitioned into 460 * ACPI_EC_COMMAND_POLL state immediately. 461 */ 462 if (ec_event_clearing == ACPI_EC_EVT_TIMING_STATUS || 463 ec_event_clearing == ACPI_EC_EVT_TIMING_QUERY || 464 !test_bit(EC_FLAGS_QUERY_PENDING, &ec->flags) || 465 (ec->curr && ec->curr->command == ACPI_EC_COMMAND_QUERY)) 466 guarded = false; 467 spin_unlock_irqrestore(&ec->lock, flags); 468 return guarded; 469 } 470 471 static int ec_transaction_polled(struct acpi_ec *ec) 472 { 473 unsigned long flags; 474 int ret = 0; 475 476 spin_lock_irqsave(&ec->lock, flags); 477 if (ec->curr && (ec->curr->flags & ACPI_EC_COMMAND_POLL)) 478 ret = 1; 479 spin_unlock_irqrestore(&ec->lock, flags); 480 return ret; 481 } 482 483 static int ec_transaction_completed(struct acpi_ec *ec) 484 { 485 unsigned long flags; 486 int ret = 0; 487 488 spin_lock_irqsave(&ec->lock, flags); 489 if (ec->curr && (ec->curr->flags & ACPI_EC_COMMAND_COMPLETE)) 490 ret = 1; 491 spin_unlock_irqrestore(&ec->lock, flags); 492 return ret; 493 } 494 495 static inline void ec_transaction_transition(struct acpi_ec *ec, unsigned long flag) 496 { 497 ec->curr->flags |= flag; 498 if (ec->curr->command == ACPI_EC_COMMAND_QUERY) { 499 if (ec_event_clearing == ACPI_EC_EVT_TIMING_STATUS && 500 flag == ACPI_EC_COMMAND_POLL) 501 acpi_ec_complete_query(ec); 502 if (ec_event_clearing == ACPI_EC_EVT_TIMING_QUERY && 503 flag == ACPI_EC_COMMAND_COMPLETE) 504 acpi_ec_complete_query(ec); 505 if (ec_event_clearing == ACPI_EC_EVT_TIMING_EVENT && 506 flag == ACPI_EC_COMMAND_COMPLETE) 507 set_bit(EC_FLAGS_QUERY_GUARDING, &ec->flags); 508 } 509 } 510 511 static void advance_transaction(struct acpi_ec *ec) 512 { 513 struct transaction *t; 514 u8 status; 515 bool wakeup = false; 516 517 ec_dbg_stm("%s (%d)", in_interrupt() ? "IRQ" : "TASK", 518 smp_processor_id()); 519 /* 520 * By always clearing STS before handling all indications, we can 521 * ensure a hardware STS 0->1 change after this clearing can always 522 * trigger a GPE interrupt. 523 */ 524 acpi_ec_clear_gpe(ec); 525 status = acpi_ec_read_status(ec); 526 t = ec->curr; 527 /* 528 * Another IRQ or a guarded polling mode advancement is detected, 529 * the next QR_EC submission is then allowed. 530 */ 531 if (!t || !(t->flags & ACPI_EC_COMMAND_POLL)) { 532 if (ec_event_clearing == ACPI_EC_EVT_TIMING_EVENT && 533 (!ec->nr_pending_queries || 534 test_bit(EC_FLAGS_QUERY_GUARDING, &ec->flags))) { 535 clear_bit(EC_FLAGS_QUERY_GUARDING, &ec->flags); 536 acpi_ec_complete_query(ec); 537 } 538 } 539 if (!t) 540 goto err; 541 if (t->flags & ACPI_EC_COMMAND_POLL) { 542 if (t->wlen > t->wi) { 543 if ((status & ACPI_EC_FLAG_IBF) == 0) 544 acpi_ec_write_data(ec, t->wdata[t->wi++]); 545 else 546 goto err; 547 } else if (t->rlen > t->ri) { 548 if ((status & ACPI_EC_FLAG_OBF) == 1) { 549 t->rdata[t->ri++] = acpi_ec_read_data(ec); 550 if (t->rlen == t->ri) { 551 ec_transaction_transition(ec, ACPI_EC_COMMAND_COMPLETE); 552 if (t->command == ACPI_EC_COMMAND_QUERY) 553 ec_dbg_evt("Command(%s) completed by hardware", 554 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY)); 555 wakeup = true; 556 } 557 } else 558 goto err; 559 } else if (t->wlen == t->wi && 560 (status & ACPI_EC_FLAG_IBF) == 0) { 561 ec_transaction_transition(ec, ACPI_EC_COMMAND_COMPLETE); 562 wakeup = true; 563 } 564 goto out; 565 } else { 566 if (EC_FLAGS_QUERY_HANDSHAKE && 567 !(status & ACPI_EC_FLAG_SCI) && 568 (t->command == ACPI_EC_COMMAND_QUERY)) { 569 ec_transaction_transition(ec, ACPI_EC_COMMAND_POLL); 570 t->rdata[t->ri++] = 0x00; 571 ec_transaction_transition(ec, ACPI_EC_COMMAND_COMPLETE); 572 ec_dbg_evt("Command(%s) completed by software", 573 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY)); 574 wakeup = true; 575 } else if ((status & ACPI_EC_FLAG_IBF) == 0) { 576 acpi_ec_write_cmd(ec, t->command); 577 ec_transaction_transition(ec, ACPI_EC_COMMAND_POLL); 578 } else 579 goto err; 580 goto out; 581 } 582 err: 583 /* 584 * If SCI bit is set, then don't think it's a false IRQ 585 * otherwise will take a not handled IRQ as a false one. 586 */ 587 if (!(status & ACPI_EC_FLAG_SCI)) { 588 if (in_interrupt() && t) { 589 if (t->irq_count < ec_storm_threshold) 590 ++t->irq_count; 591 /* Allow triggering on 0 threshold */ 592 if (t->irq_count == ec_storm_threshold) 593 acpi_ec_set_storm(ec, EC_FLAGS_COMMAND_STORM); 594 } 595 } 596 out: 597 if (status & ACPI_EC_FLAG_SCI) 598 acpi_ec_submit_query(ec); 599 if (wakeup && in_interrupt()) 600 wake_up(&ec->wait); 601 } 602 603 static void start_transaction(struct acpi_ec *ec) 604 { 605 ec->curr->irq_count = ec->curr->wi = ec->curr->ri = 0; 606 ec->curr->flags = 0; 607 } 608 609 static int ec_guard(struct acpi_ec *ec) 610 { 611 unsigned long guard = usecs_to_jiffies(ec_polling_guard); 612 unsigned long timeout = ec->timestamp + guard; 613 614 /* Ensure guarding period before polling EC status */ 615 do { 616 if (ec_busy_polling) { 617 /* Perform busy polling */ 618 if (ec_transaction_completed(ec)) 619 return 0; 620 udelay(jiffies_to_usecs(guard)); 621 } else { 622 /* 623 * Perform wait polling 624 * 1. Wait the transaction to be completed by the 625 * GPE handler after the transaction enters 626 * ACPI_EC_COMMAND_POLL state. 627 * 2. A special guarding logic is also required 628 * for event clearing mode "event" before the 629 * transaction enters ACPI_EC_COMMAND_POLL 630 * state. 631 */ 632 if (!ec_transaction_polled(ec) && 633 !acpi_ec_guard_event(ec)) 634 break; 635 if (wait_event_timeout(ec->wait, 636 ec_transaction_completed(ec), 637 guard)) 638 return 0; 639 } 640 } while (time_before(jiffies, timeout)); 641 return -ETIME; 642 } 643 644 static int ec_poll(struct acpi_ec *ec) 645 { 646 unsigned long flags; 647 int repeat = 5; /* number of command restarts */ 648 649 while (repeat--) { 650 unsigned long delay = jiffies + 651 msecs_to_jiffies(ec_delay); 652 do { 653 if (!ec_guard(ec)) 654 return 0; 655 spin_lock_irqsave(&ec->lock, flags); 656 advance_transaction(ec); 657 spin_unlock_irqrestore(&ec->lock, flags); 658 } while (time_before(jiffies, delay)); 659 pr_debug("controller reset, restart transaction\n"); 660 spin_lock_irqsave(&ec->lock, flags); 661 start_transaction(ec); 662 spin_unlock_irqrestore(&ec->lock, flags); 663 } 664 return -ETIME; 665 } 666 667 static int acpi_ec_transaction_unlocked(struct acpi_ec *ec, 668 struct transaction *t) 669 { 670 unsigned long tmp; 671 int ret = 0; 672 673 /* start transaction */ 674 spin_lock_irqsave(&ec->lock, tmp); 675 /* Enable GPE for command processing (IBF=0/OBF=1) */ 676 if (!acpi_ec_submit_flushable_request(ec)) { 677 ret = -EINVAL; 678 goto unlock; 679 } 680 ec_dbg_ref(ec, "Increase command"); 681 /* following two actions should be kept atomic */ 682 ec->curr = t; 683 ec_dbg_req("Command(%s) started", acpi_ec_cmd_string(t->command)); 684 start_transaction(ec); 685 spin_unlock_irqrestore(&ec->lock, tmp); 686 687 ret = ec_poll(ec); 688 689 spin_lock_irqsave(&ec->lock, tmp); 690 if (t->irq_count == ec_storm_threshold) 691 acpi_ec_clear_storm(ec, EC_FLAGS_COMMAND_STORM); 692 ec_dbg_req("Command(%s) stopped", acpi_ec_cmd_string(t->command)); 693 ec->curr = NULL; 694 /* Disable GPE for command processing (IBF=0/OBF=1) */ 695 acpi_ec_complete_request(ec); 696 ec_dbg_ref(ec, "Decrease command"); 697 unlock: 698 spin_unlock_irqrestore(&ec->lock, tmp); 699 return ret; 700 } 701 702 static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t) 703 { 704 int status; 705 u32 glk; 706 707 if (!ec || (!t) || (t->wlen && !t->wdata) || (t->rlen && !t->rdata)) 708 return -EINVAL; 709 if (t->rdata) 710 memset(t->rdata, 0, t->rlen); 711 712 mutex_lock(&ec->mutex); 713 if (ec->global_lock) { 714 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk); 715 if (ACPI_FAILURE(status)) { 716 status = -ENODEV; 717 goto unlock; 718 } 719 } 720 721 status = acpi_ec_transaction_unlocked(ec, t); 722 723 if (ec->global_lock) 724 acpi_release_global_lock(glk); 725 unlock: 726 mutex_unlock(&ec->mutex); 727 return status; 728 } 729 730 static int acpi_ec_burst_enable(struct acpi_ec *ec) 731 { 732 u8 d; 733 struct transaction t = {.command = ACPI_EC_BURST_ENABLE, 734 .wdata = NULL, .rdata = &d, 735 .wlen = 0, .rlen = 1}; 736 737 return acpi_ec_transaction(ec, &t); 738 } 739 740 static int acpi_ec_burst_disable(struct acpi_ec *ec) 741 { 742 struct transaction t = {.command = ACPI_EC_BURST_DISABLE, 743 .wdata = NULL, .rdata = NULL, 744 .wlen = 0, .rlen = 0}; 745 746 return (acpi_ec_read_status(ec) & ACPI_EC_FLAG_BURST) ? 747 acpi_ec_transaction(ec, &t) : 0; 748 } 749 750 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 *data) 751 { 752 int result; 753 u8 d; 754 struct transaction t = {.command = ACPI_EC_COMMAND_READ, 755 .wdata = &address, .rdata = &d, 756 .wlen = 1, .rlen = 1}; 757 758 result = acpi_ec_transaction(ec, &t); 759 *data = d; 760 return result; 761 } 762 763 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data) 764 { 765 u8 wdata[2] = { address, data }; 766 struct transaction t = {.command = ACPI_EC_COMMAND_WRITE, 767 .wdata = wdata, .rdata = NULL, 768 .wlen = 2, .rlen = 0}; 769 770 return acpi_ec_transaction(ec, &t); 771 } 772 773 int ec_read(u8 addr, u8 *val) 774 { 775 int err; 776 u8 temp_data; 777 778 if (!first_ec) 779 return -ENODEV; 780 781 err = acpi_ec_read(first_ec, addr, &temp_data); 782 783 if (!err) { 784 *val = temp_data; 785 return 0; 786 } 787 return err; 788 } 789 EXPORT_SYMBOL(ec_read); 790 791 int ec_write(u8 addr, u8 val) 792 { 793 int err; 794 795 if (!first_ec) 796 return -ENODEV; 797 798 err = acpi_ec_write(first_ec, addr, val); 799 800 return err; 801 } 802 EXPORT_SYMBOL(ec_write); 803 804 int ec_transaction(u8 command, 805 const u8 *wdata, unsigned wdata_len, 806 u8 *rdata, unsigned rdata_len) 807 { 808 struct transaction t = {.command = command, 809 .wdata = wdata, .rdata = rdata, 810 .wlen = wdata_len, .rlen = rdata_len}; 811 812 if (!first_ec) 813 return -ENODEV; 814 815 return acpi_ec_transaction(first_ec, &t); 816 } 817 EXPORT_SYMBOL(ec_transaction); 818 819 /* Get the handle to the EC device */ 820 acpi_handle ec_get_handle(void) 821 { 822 if (!first_ec) 823 return NULL; 824 return first_ec->handle; 825 } 826 EXPORT_SYMBOL(ec_get_handle); 827 828 /* 829 * Process _Q events that might have accumulated in the EC. 830 * Run with locked ec mutex. 831 */ 832 static void acpi_ec_clear(struct acpi_ec *ec) 833 { 834 int i, status; 835 u8 value = 0; 836 837 for (i = 0; i < ACPI_EC_CLEAR_MAX; i++) { 838 status = acpi_ec_query(ec, &value); 839 if (status || !value) 840 break; 841 } 842 843 if (unlikely(i == ACPI_EC_CLEAR_MAX)) 844 pr_warn("Warning: Maximum of %d stale EC events cleared\n", i); 845 else 846 pr_info("%d stale EC events cleared\n", i); 847 } 848 849 static void acpi_ec_start(struct acpi_ec *ec, bool resuming) 850 { 851 unsigned long flags; 852 853 spin_lock_irqsave(&ec->lock, flags); 854 if (!test_and_set_bit(EC_FLAGS_STARTED, &ec->flags)) { 855 ec_dbg_drv("Starting EC"); 856 /* Enable GPE for event processing (SCI_EVT=1) */ 857 if (!resuming) { 858 acpi_ec_submit_request(ec); 859 ec_dbg_ref(ec, "Increase driver"); 860 } 861 ec_log_drv("EC started"); 862 } 863 spin_unlock_irqrestore(&ec->lock, flags); 864 } 865 866 static bool acpi_ec_stopped(struct acpi_ec *ec) 867 { 868 unsigned long flags; 869 bool flushed; 870 871 spin_lock_irqsave(&ec->lock, flags); 872 flushed = acpi_ec_flushed(ec); 873 spin_unlock_irqrestore(&ec->lock, flags); 874 return flushed; 875 } 876 877 static void acpi_ec_stop(struct acpi_ec *ec, bool suspending) 878 { 879 unsigned long flags; 880 881 spin_lock_irqsave(&ec->lock, flags); 882 if (acpi_ec_started(ec)) { 883 ec_dbg_drv("Stopping EC"); 884 set_bit(EC_FLAGS_STOPPED, &ec->flags); 885 spin_unlock_irqrestore(&ec->lock, flags); 886 wait_event(ec->wait, acpi_ec_stopped(ec)); 887 spin_lock_irqsave(&ec->lock, flags); 888 /* Disable GPE for event processing (SCI_EVT=1) */ 889 if (!suspending) { 890 acpi_ec_complete_request(ec); 891 ec_dbg_ref(ec, "Decrease driver"); 892 } 893 clear_bit(EC_FLAGS_STARTED, &ec->flags); 894 clear_bit(EC_FLAGS_STOPPED, &ec->flags); 895 ec_log_drv("EC stopped"); 896 } 897 spin_unlock_irqrestore(&ec->lock, flags); 898 } 899 900 void acpi_ec_block_transactions(void) 901 { 902 struct acpi_ec *ec = first_ec; 903 904 if (!ec) 905 return; 906 907 mutex_lock(&ec->mutex); 908 /* Prevent transactions from being carried out */ 909 acpi_ec_stop(ec, true); 910 mutex_unlock(&ec->mutex); 911 } 912 913 void acpi_ec_unblock_transactions(void) 914 { 915 struct acpi_ec *ec = first_ec; 916 917 if (!ec) 918 return; 919 920 /* Allow transactions to be carried out again */ 921 acpi_ec_start(ec, true); 922 923 if (EC_FLAGS_CLEAR_ON_RESUME) 924 acpi_ec_clear(ec); 925 } 926 927 void acpi_ec_unblock_transactions_early(void) 928 { 929 /* 930 * Allow transactions to happen again (this function is called from 931 * atomic context during wakeup, so we don't need to acquire the mutex). 932 */ 933 if (first_ec) 934 acpi_ec_start(first_ec, true); 935 } 936 937 /* -------------------------------------------------------------------------- 938 Event Management 939 -------------------------------------------------------------------------- */ 940 static struct acpi_ec_query_handler * 941 acpi_ec_get_query_handler(struct acpi_ec_query_handler *handler) 942 { 943 if (handler) 944 kref_get(&handler->kref); 945 return handler; 946 } 947 948 static struct acpi_ec_query_handler * 949 acpi_ec_get_query_handler_by_value(struct acpi_ec *ec, u8 value) 950 { 951 struct acpi_ec_query_handler *handler; 952 bool found = false; 953 954 mutex_lock(&ec->mutex); 955 list_for_each_entry(handler, &ec->list, node) { 956 if (value == handler->query_bit) { 957 found = true; 958 break; 959 } 960 } 961 mutex_unlock(&ec->mutex); 962 return found ? acpi_ec_get_query_handler(handler) : NULL; 963 } 964 965 static void acpi_ec_query_handler_release(struct kref *kref) 966 { 967 struct acpi_ec_query_handler *handler = 968 container_of(kref, struct acpi_ec_query_handler, kref); 969 970 kfree(handler); 971 } 972 973 static void acpi_ec_put_query_handler(struct acpi_ec_query_handler *handler) 974 { 975 kref_put(&handler->kref, acpi_ec_query_handler_release); 976 } 977 978 int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit, 979 acpi_handle handle, acpi_ec_query_func func, 980 void *data) 981 { 982 struct acpi_ec_query_handler *handler = 983 kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL); 984 985 if (!handler) 986 return -ENOMEM; 987 988 handler->query_bit = query_bit; 989 handler->handle = handle; 990 handler->func = func; 991 handler->data = data; 992 mutex_lock(&ec->mutex); 993 kref_init(&handler->kref); 994 list_add(&handler->node, &ec->list); 995 mutex_unlock(&ec->mutex); 996 return 0; 997 } 998 EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler); 999 1000 static void acpi_ec_remove_query_handlers(struct acpi_ec *ec, 1001 bool remove_all, u8 query_bit) 1002 { 1003 struct acpi_ec_query_handler *handler, *tmp; 1004 LIST_HEAD(free_list); 1005 1006 mutex_lock(&ec->mutex); 1007 list_for_each_entry_safe(handler, tmp, &ec->list, node) { 1008 if (remove_all || query_bit == handler->query_bit) { 1009 list_del_init(&handler->node); 1010 list_add(&handler->node, &free_list); 1011 } 1012 } 1013 mutex_unlock(&ec->mutex); 1014 list_for_each_entry_safe(handler, tmp, &free_list, node) 1015 acpi_ec_put_query_handler(handler); 1016 } 1017 1018 void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit) 1019 { 1020 acpi_ec_remove_query_handlers(ec, false, query_bit); 1021 } 1022 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler); 1023 1024 static struct acpi_ec_query *acpi_ec_create_query(u8 *pval) 1025 { 1026 struct acpi_ec_query *q; 1027 struct transaction *t; 1028 1029 q = kzalloc(sizeof (struct acpi_ec_query), GFP_KERNEL); 1030 if (!q) 1031 return NULL; 1032 INIT_WORK(&q->work, acpi_ec_event_processor); 1033 t = &q->transaction; 1034 t->command = ACPI_EC_COMMAND_QUERY; 1035 t->rdata = pval; 1036 t->rlen = 1; 1037 return q; 1038 } 1039 1040 static void acpi_ec_delete_query(struct acpi_ec_query *q) 1041 { 1042 if (q) { 1043 if (q->handler) 1044 acpi_ec_put_query_handler(q->handler); 1045 kfree(q); 1046 } 1047 } 1048 1049 static void acpi_ec_event_processor(struct work_struct *work) 1050 { 1051 struct acpi_ec_query *q = container_of(work, struct acpi_ec_query, work); 1052 struct acpi_ec_query_handler *handler = q->handler; 1053 1054 ec_dbg_evt("Query(0x%02x) started", handler->query_bit); 1055 if (handler->func) 1056 handler->func(handler->data); 1057 else if (handler->handle) 1058 acpi_evaluate_object(handler->handle, NULL, NULL, NULL); 1059 ec_dbg_evt("Query(0x%02x) stopped", handler->query_bit); 1060 acpi_ec_delete_query(q); 1061 } 1062 1063 static int acpi_ec_query(struct acpi_ec *ec, u8 *data) 1064 { 1065 u8 value = 0; 1066 int result; 1067 struct acpi_ec_query *q; 1068 1069 q = acpi_ec_create_query(&value); 1070 if (!q) 1071 return -ENOMEM; 1072 1073 /* 1074 * Query the EC to find out which _Qxx method we need to evaluate. 1075 * Note that successful completion of the query causes the ACPI_EC_SCI 1076 * bit to be cleared (and thus clearing the interrupt source). 1077 */ 1078 result = acpi_ec_transaction(ec, &q->transaction); 1079 if (!value) 1080 result = -ENODATA; 1081 if (result) 1082 goto err_exit; 1083 1084 q->handler = acpi_ec_get_query_handler_by_value(ec, value); 1085 if (!q->handler) { 1086 result = -ENODATA; 1087 goto err_exit; 1088 } 1089 1090 /* 1091 * It is reported that _Qxx are evaluated in a parallel way on 1092 * Windows: 1093 * https://bugzilla.kernel.org/show_bug.cgi?id=94411 1094 * 1095 * Put this log entry before schedule_work() in order to make 1096 * it appearing before any other log entries occurred during the 1097 * work queue execution. 1098 */ 1099 ec_dbg_evt("Query(0x%02x) scheduled", value); 1100 if (!schedule_work(&q->work)) { 1101 ec_dbg_evt("Query(0x%02x) overlapped", value); 1102 result = -EBUSY; 1103 } 1104 1105 err_exit: 1106 if (result) 1107 acpi_ec_delete_query(q); 1108 if (data) 1109 *data = value; 1110 return result; 1111 } 1112 1113 static void acpi_ec_check_event(struct acpi_ec *ec) 1114 { 1115 unsigned long flags; 1116 1117 if (ec_event_clearing == ACPI_EC_EVT_TIMING_EVENT) { 1118 if (ec_guard(ec)) { 1119 spin_lock_irqsave(&ec->lock, flags); 1120 /* 1121 * Take care of the SCI_EVT unless no one else is 1122 * taking care of it. 1123 */ 1124 if (!ec->curr) 1125 advance_transaction(ec); 1126 spin_unlock_irqrestore(&ec->lock, flags); 1127 } 1128 } 1129 } 1130 1131 static void acpi_ec_event_handler(struct work_struct *work) 1132 { 1133 unsigned long flags; 1134 struct acpi_ec *ec = container_of(work, struct acpi_ec, work); 1135 1136 ec_dbg_evt("Event started"); 1137 1138 spin_lock_irqsave(&ec->lock, flags); 1139 while (ec->nr_pending_queries) { 1140 spin_unlock_irqrestore(&ec->lock, flags); 1141 (void)acpi_ec_query(ec, NULL); 1142 spin_lock_irqsave(&ec->lock, flags); 1143 ec->nr_pending_queries--; 1144 /* 1145 * Before exit, make sure that this work item can be 1146 * scheduled again. There might be QR_EC failures, leaving 1147 * EC_FLAGS_QUERY_PENDING uncleared and preventing this work 1148 * item from being scheduled again. 1149 */ 1150 if (!ec->nr_pending_queries) { 1151 if (ec_event_clearing == ACPI_EC_EVT_TIMING_STATUS || 1152 ec_event_clearing == ACPI_EC_EVT_TIMING_QUERY) 1153 acpi_ec_complete_query(ec); 1154 } 1155 } 1156 spin_unlock_irqrestore(&ec->lock, flags); 1157 1158 ec_dbg_evt("Event stopped"); 1159 1160 acpi_ec_check_event(ec); 1161 } 1162 1163 static u32 acpi_ec_gpe_handler(acpi_handle gpe_device, 1164 u32 gpe_number, void *data) 1165 { 1166 unsigned long flags; 1167 struct acpi_ec *ec = data; 1168 1169 spin_lock_irqsave(&ec->lock, flags); 1170 advance_transaction(ec); 1171 spin_unlock_irqrestore(&ec->lock, flags); 1172 return ACPI_INTERRUPT_HANDLED; 1173 } 1174 1175 /* -------------------------------------------------------------------------- 1176 * Address Space Management 1177 * -------------------------------------------------------------------------- */ 1178 1179 static acpi_status 1180 acpi_ec_space_handler(u32 function, acpi_physical_address address, 1181 u32 bits, u64 *value64, 1182 void *handler_context, void *region_context) 1183 { 1184 struct acpi_ec *ec = handler_context; 1185 int result = 0, i, bytes = bits / 8; 1186 u8 *value = (u8 *)value64; 1187 1188 if ((address > 0xFF) || !value || !handler_context) 1189 return AE_BAD_PARAMETER; 1190 1191 if (function != ACPI_READ && function != ACPI_WRITE) 1192 return AE_BAD_PARAMETER; 1193 1194 if (ec_busy_polling || bits > 8) 1195 acpi_ec_burst_enable(ec); 1196 1197 for (i = 0; i < bytes; ++i, ++address, ++value) 1198 result = (function == ACPI_READ) ? 1199 acpi_ec_read(ec, address, value) : 1200 acpi_ec_write(ec, address, *value); 1201 1202 if (ec_busy_polling || bits > 8) 1203 acpi_ec_burst_disable(ec); 1204 1205 switch (result) { 1206 case -EINVAL: 1207 return AE_BAD_PARAMETER; 1208 case -ENODEV: 1209 return AE_NOT_FOUND; 1210 case -ETIME: 1211 return AE_TIME; 1212 default: 1213 return AE_OK; 1214 } 1215 } 1216 1217 /* -------------------------------------------------------------------------- 1218 * Driver Interface 1219 * -------------------------------------------------------------------------- */ 1220 1221 static acpi_status 1222 ec_parse_io_ports(struct acpi_resource *resource, void *context); 1223 1224 static struct acpi_ec *make_acpi_ec(void) 1225 { 1226 struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL); 1227 1228 if (!ec) 1229 return NULL; 1230 ec->flags = 1 << EC_FLAGS_QUERY_PENDING; 1231 mutex_init(&ec->mutex); 1232 init_waitqueue_head(&ec->wait); 1233 INIT_LIST_HEAD(&ec->list); 1234 spin_lock_init(&ec->lock); 1235 INIT_WORK(&ec->work, acpi_ec_event_handler); 1236 ec->timestamp = jiffies; 1237 return ec; 1238 } 1239 1240 static acpi_status 1241 acpi_ec_register_query_methods(acpi_handle handle, u32 level, 1242 void *context, void **return_value) 1243 { 1244 char node_name[5]; 1245 struct acpi_buffer buffer = { sizeof(node_name), node_name }; 1246 struct acpi_ec *ec = context; 1247 int value = 0; 1248 acpi_status status; 1249 1250 status = acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer); 1251 1252 if (ACPI_SUCCESS(status) && sscanf(node_name, "_Q%x", &value) == 1) 1253 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL); 1254 return AE_OK; 1255 } 1256 1257 static acpi_status 1258 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval) 1259 { 1260 acpi_status status; 1261 unsigned long long tmp = 0; 1262 struct acpi_ec *ec = context; 1263 1264 /* clear addr values, ec_parse_io_ports depend on it */ 1265 ec->command_addr = ec->data_addr = 0; 1266 1267 status = acpi_walk_resources(handle, METHOD_NAME__CRS, 1268 ec_parse_io_ports, ec); 1269 if (ACPI_FAILURE(status)) 1270 return status; 1271 1272 /* Get GPE bit assignment (EC events). */ 1273 /* TODO: Add support for _GPE returning a package */ 1274 status = acpi_evaluate_integer(handle, "_GPE", NULL, &tmp); 1275 if (ACPI_FAILURE(status)) 1276 return status; 1277 ec->gpe = tmp; 1278 /* Use the global lock for all EC transactions? */ 1279 tmp = 0; 1280 acpi_evaluate_integer(handle, "_GLK", NULL, &tmp); 1281 ec->global_lock = tmp; 1282 ec->handle = handle; 1283 return AE_CTRL_TERMINATE; 1284 } 1285 1286 static int ec_install_handlers(struct acpi_ec *ec) 1287 { 1288 acpi_status status; 1289 1290 if (test_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags)) 1291 return 0; 1292 status = acpi_install_gpe_raw_handler(NULL, ec->gpe, 1293 ACPI_GPE_EDGE_TRIGGERED, 1294 &acpi_ec_gpe_handler, ec); 1295 if (ACPI_FAILURE(status)) 1296 return -ENODEV; 1297 1298 acpi_ec_start(ec, false); 1299 status = acpi_install_address_space_handler(ec->handle, 1300 ACPI_ADR_SPACE_EC, 1301 &acpi_ec_space_handler, 1302 NULL, ec); 1303 if (ACPI_FAILURE(status)) { 1304 if (status == AE_NOT_FOUND) { 1305 /* 1306 * Maybe OS fails in evaluating the _REG object. 1307 * The AE_NOT_FOUND error will be ignored and OS 1308 * continue to initialize EC. 1309 */ 1310 pr_err("Fail in evaluating the _REG object" 1311 " of EC device. Broken bios is suspected.\n"); 1312 } else { 1313 acpi_ec_stop(ec, false); 1314 acpi_remove_gpe_handler(NULL, ec->gpe, 1315 &acpi_ec_gpe_handler); 1316 return -ENODEV; 1317 } 1318 } 1319 1320 set_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags); 1321 return 0; 1322 } 1323 1324 static void ec_remove_handlers(struct acpi_ec *ec) 1325 { 1326 if (!test_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags)) 1327 return; 1328 acpi_ec_stop(ec, false); 1329 if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle, 1330 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler))) 1331 pr_err("failed to remove space handler\n"); 1332 if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe, 1333 &acpi_ec_gpe_handler))) 1334 pr_err("failed to remove gpe handler\n"); 1335 clear_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags); 1336 } 1337 1338 static int acpi_ec_add(struct acpi_device *device) 1339 { 1340 struct acpi_ec *ec = NULL; 1341 int ret; 1342 1343 strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME); 1344 strcpy(acpi_device_class(device), ACPI_EC_CLASS); 1345 1346 /* Check for boot EC */ 1347 if (boot_ec && 1348 (boot_ec->handle == device->handle || 1349 boot_ec->handle == ACPI_ROOT_OBJECT)) { 1350 ec = boot_ec; 1351 boot_ec = NULL; 1352 } else { 1353 ec = make_acpi_ec(); 1354 if (!ec) 1355 return -ENOMEM; 1356 } 1357 if (ec_parse_device(device->handle, 0, ec, NULL) != 1358 AE_CTRL_TERMINATE) { 1359 kfree(ec); 1360 return -EINVAL; 1361 } 1362 1363 /* Find and register all query methods */ 1364 acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1, 1365 acpi_ec_register_query_methods, NULL, ec, NULL); 1366 1367 if (!first_ec) 1368 first_ec = ec; 1369 device->driver_data = ec; 1370 1371 ret = !!request_region(ec->data_addr, 1, "EC data"); 1372 WARN(!ret, "Could not request EC data io port 0x%lx", ec->data_addr); 1373 ret = !!request_region(ec->command_addr, 1, "EC cmd"); 1374 WARN(!ret, "Could not request EC cmd io port 0x%lx", ec->command_addr); 1375 1376 pr_info("GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n", 1377 ec->gpe, ec->command_addr, ec->data_addr); 1378 1379 ret = ec_install_handlers(ec); 1380 1381 /* Reprobe devices depending on the EC */ 1382 acpi_walk_dep_device_list(ec->handle); 1383 1384 /* EC is fully operational, allow queries */ 1385 clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags); 1386 1387 /* Clear stale _Q events if hardware might require that */ 1388 if (EC_FLAGS_CLEAR_ON_RESUME) 1389 acpi_ec_clear(ec); 1390 return ret; 1391 } 1392 1393 static int acpi_ec_remove(struct acpi_device *device) 1394 { 1395 struct acpi_ec *ec; 1396 1397 if (!device) 1398 return -EINVAL; 1399 1400 ec = acpi_driver_data(device); 1401 ec_remove_handlers(ec); 1402 acpi_ec_remove_query_handlers(ec, true, 0); 1403 release_region(ec->data_addr, 1); 1404 release_region(ec->command_addr, 1); 1405 device->driver_data = NULL; 1406 if (ec == first_ec) 1407 first_ec = NULL; 1408 kfree(ec); 1409 return 0; 1410 } 1411 1412 static acpi_status 1413 ec_parse_io_ports(struct acpi_resource *resource, void *context) 1414 { 1415 struct acpi_ec *ec = context; 1416 1417 if (resource->type != ACPI_RESOURCE_TYPE_IO) 1418 return AE_OK; 1419 1420 /* 1421 * The first address region returned is the data port, and 1422 * the second address region returned is the status/command 1423 * port. 1424 */ 1425 if (ec->data_addr == 0) 1426 ec->data_addr = resource->data.io.minimum; 1427 else if (ec->command_addr == 0) 1428 ec->command_addr = resource->data.io.minimum; 1429 else 1430 return AE_CTRL_TERMINATE; 1431 1432 return AE_OK; 1433 } 1434 1435 int __init acpi_boot_ec_enable(void) 1436 { 1437 if (!boot_ec || test_bit(EC_FLAGS_HANDLERS_INSTALLED, &boot_ec->flags)) 1438 return 0; 1439 if (!ec_install_handlers(boot_ec)) { 1440 first_ec = boot_ec; 1441 return 0; 1442 } 1443 return -EFAULT; 1444 } 1445 1446 static const struct acpi_device_id ec_device_ids[] = { 1447 {"PNP0C09", 0}, 1448 {"", 0}, 1449 }; 1450 1451 /* Some BIOS do not survive early DSDT scan, skip it */ 1452 static int ec_skip_dsdt_scan(const struct dmi_system_id *id) 1453 { 1454 EC_FLAGS_SKIP_DSDT_SCAN = 1; 1455 return 0; 1456 } 1457 1458 /* ASUStek often supplies us with broken ECDT, validate it */ 1459 static int ec_validate_ecdt(const struct dmi_system_id *id) 1460 { 1461 EC_FLAGS_VALIDATE_ECDT = 1; 1462 return 0; 1463 } 1464 1465 #if 0 1466 /* 1467 * Some EC firmware variations refuses to respond QR_EC when SCI_EVT is not 1468 * set, for which case, we complete the QR_EC without issuing it to the 1469 * firmware. 1470 * https://bugzilla.kernel.org/show_bug.cgi?id=82611 1471 * https://bugzilla.kernel.org/show_bug.cgi?id=97381 1472 */ 1473 static int ec_flag_query_handshake(const struct dmi_system_id *id) 1474 { 1475 pr_debug("Detected the EC firmware requiring QR_EC issued when SCI_EVT set\n"); 1476 EC_FLAGS_QUERY_HANDSHAKE = 1; 1477 return 0; 1478 } 1479 #endif 1480 1481 /* 1482 * On some hardware it is necessary to clear events accumulated by the EC during 1483 * sleep. These ECs stop reporting GPEs until they are manually polled, if too 1484 * many events are accumulated. (e.g. Samsung Series 5/9 notebooks) 1485 * 1486 * https://bugzilla.kernel.org/show_bug.cgi?id=44161 1487 * 1488 * Ideally, the EC should also be instructed NOT to accumulate events during 1489 * sleep (which Windows seems to do somehow), but the interface to control this 1490 * behaviour is not known at this time. 1491 * 1492 * Models known to be affected are Samsung 530Uxx/535Uxx/540Uxx/550Pxx/900Xxx, 1493 * however it is very likely that other Samsung models are affected. 1494 * 1495 * On systems which don't accumulate _Q events during sleep, this extra check 1496 * should be harmless. 1497 */ 1498 static int ec_clear_on_resume(const struct dmi_system_id *id) 1499 { 1500 pr_debug("Detected system needing EC poll on resume.\n"); 1501 EC_FLAGS_CLEAR_ON_RESUME = 1; 1502 ec_event_clearing = ACPI_EC_EVT_TIMING_STATUS; 1503 return 0; 1504 } 1505 1506 static struct dmi_system_id ec_dmi_table[] __initdata = { 1507 { 1508 ec_skip_dsdt_scan, "Compal JFL92", { 1509 DMI_MATCH(DMI_BIOS_VENDOR, "COMPAL"), 1510 DMI_MATCH(DMI_BOARD_NAME, "JFL92") }, NULL}, 1511 { 1512 ec_validate_ecdt, "MSI MS-171F", { 1513 DMI_MATCH(DMI_SYS_VENDOR, "Micro-Star"), 1514 DMI_MATCH(DMI_PRODUCT_NAME, "MS-171F"),}, NULL}, 1515 { 1516 ec_validate_ecdt, "ASUS hardware", { 1517 DMI_MATCH(DMI_BIOS_VENDOR, "ASUS") }, NULL}, 1518 { 1519 ec_validate_ecdt, "ASUS hardware", { 1520 DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer Inc.") }, NULL}, 1521 { 1522 ec_skip_dsdt_scan, "HP Folio 13", { 1523 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"), 1524 DMI_MATCH(DMI_PRODUCT_NAME, "HP Folio 13"),}, NULL}, 1525 { 1526 ec_validate_ecdt, "ASUS hardware", { 1527 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTek Computer Inc."), 1528 DMI_MATCH(DMI_PRODUCT_NAME, "L4R"),}, NULL}, 1529 { 1530 ec_clear_on_resume, "Samsung hardware", { 1531 DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD.")}, NULL}, 1532 {}, 1533 }; 1534 1535 int __init acpi_ec_ecdt_probe(void) 1536 { 1537 acpi_status status; 1538 struct acpi_ec *saved_ec = NULL; 1539 struct acpi_table_ecdt *ecdt_ptr; 1540 1541 boot_ec = make_acpi_ec(); 1542 if (!boot_ec) 1543 return -ENOMEM; 1544 /* 1545 * Generate a boot ec context 1546 */ 1547 dmi_check_system(ec_dmi_table); 1548 status = acpi_get_table(ACPI_SIG_ECDT, 1, 1549 (struct acpi_table_header **)&ecdt_ptr); 1550 if (ACPI_SUCCESS(status)) { 1551 pr_info("EC description table is found, configuring boot EC\n"); 1552 boot_ec->command_addr = ecdt_ptr->control.address; 1553 boot_ec->data_addr = ecdt_ptr->data.address; 1554 boot_ec->gpe = ecdt_ptr->gpe; 1555 boot_ec->handle = ACPI_ROOT_OBJECT; 1556 acpi_get_handle(ACPI_ROOT_OBJECT, ecdt_ptr->id, 1557 &boot_ec->handle); 1558 /* Don't trust ECDT, which comes from ASUSTek */ 1559 if (!EC_FLAGS_VALIDATE_ECDT) 1560 goto install; 1561 saved_ec = kmemdup(boot_ec, sizeof(struct acpi_ec), GFP_KERNEL); 1562 if (!saved_ec) 1563 return -ENOMEM; 1564 /* fall through */ 1565 } 1566 1567 if (EC_FLAGS_SKIP_DSDT_SCAN) { 1568 kfree(saved_ec); 1569 return -ENODEV; 1570 } 1571 1572 /* This workaround is needed only on some broken machines, 1573 * which require early EC, but fail to provide ECDT */ 1574 pr_debug("Look up EC in DSDT\n"); 1575 status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device, 1576 boot_ec, NULL); 1577 /* Check that acpi_get_devices actually find something */ 1578 if (ACPI_FAILURE(status) || !boot_ec->handle) 1579 goto error; 1580 if (saved_ec) { 1581 /* try to find good ECDT from ASUSTek */ 1582 if (saved_ec->command_addr != boot_ec->command_addr || 1583 saved_ec->data_addr != boot_ec->data_addr || 1584 saved_ec->gpe != boot_ec->gpe || 1585 saved_ec->handle != boot_ec->handle) 1586 pr_info("ASUSTek keeps feeding us with broken " 1587 "ECDT tables, which are very hard to workaround. " 1588 "Trying to use DSDT EC info instead. Please send " 1589 "output of acpidump to linux-acpi@vger.kernel.org\n"); 1590 kfree(saved_ec); 1591 saved_ec = NULL; 1592 } else { 1593 /* We really need to limit this workaround, the only ASUS, 1594 * which needs it, has fake EC._INI method, so use it as flag. 1595 * Keep boot_ec struct as it will be needed soon. 1596 */ 1597 if (!dmi_name_in_vendors("ASUS") || 1598 !acpi_has_method(boot_ec->handle, "_INI")) 1599 return -ENODEV; 1600 } 1601 install: 1602 if (!ec_install_handlers(boot_ec)) { 1603 first_ec = boot_ec; 1604 return 0; 1605 } 1606 error: 1607 kfree(boot_ec); 1608 kfree(saved_ec); 1609 boot_ec = NULL; 1610 return -ENODEV; 1611 } 1612 1613 static int param_set_event_clearing(const char *val, struct kernel_param *kp) 1614 { 1615 int result = 0; 1616 1617 if (!strncmp(val, "status", sizeof("status") - 1)) { 1618 ec_event_clearing = ACPI_EC_EVT_TIMING_STATUS; 1619 pr_info("Assuming SCI_EVT clearing on EC_SC accesses\n"); 1620 } else if (!strncmp(val, "query", sizeof("query") - 1)) { 1621 ec_event_clearing = ACPI_EC_EVT_TIMING_QUERY; 1622 pr_info("Assuming SCI_EVT clearing on QR_EC writes\n"); 1623 } else if (!strncmp(val, "event", sizeof("event") - 1)) { 1624 ec_event_clearing = ACPI_EC_EVT_TIMING_EVENT; 1625 pr_info("Assuming SCI_EVT clearing on event reads\n"); 1626 } else 1627 result = -EINVAL; 1628 return result; 1629 } 1630 1631 static int param_get_event_clearing(char *buffer, struct kernel_param *kp) 1632 { 1633 switch (ec_event_clearing) { 1634 case ACPI_EC_EVT_TIMING_STATUS: 1635 return sprintf(buffer, "status"); 1636 case ACPI_EC_EVT_TIMING_QUERY: 1637 return sprintf(buffer, "query"); 1638 case ACPI_EC_EVT_TIMING_EVENT: 1639 return sprintf(buffer, "event"); 1640 default: 1641 return sprintf(buffer, "invalid"); 1642 } 1643 return 0; 1644 } 1645 1646 module_param_call(ec_event_clearing, param_set_event_clearing, param_get_event_clearing, 1647 NULL, 0644); 1648 MODULE_PARM_DESC(ec_event_clearing, "Assumed SCI_EVT clearing timing"); 1649 1650 static struct acpi_driver acpi_ec_driver = { 1651 .name = "ec", 1652 .class = ACPI_EC_CLASS, 1653 .ids = ec_device_ids, 1654 .ops = { 1655 .add = acpi_ec_add, 1656 .remove = acpi_ec_remove, 1657 }, 1658 }; 1659 1660 int __init acpi_ec_init(void) 1661 { 1662 int result = 0; 1663 1664 /* Now register the driver for the EC */ 1665 result = acpi_bus_register_driver(&acpi_ec_driver); 1666 if (result < 0) 1667 return -ENODEV; 1668 1669 return result; 1670 } 1671 1672 /* EC driver currently not unloadable */ 1673 #if 0 1674 static void __exit acpi_ec_exit(void) 1675 { 1676 1677 acpi_bus_unregister_driver(&acpi_ec_driver); 1678 } 1679 #endif /* 0 */ 1680