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 #define ACPI_EC_MAX_QUERIES 16 /* Maximum number of parallel queries */ 105 106 enum { 107 EC_FLAGS_QUERY_ENABLED, /* Query is enabled */ 108 EC_FLAGS_QUERY_PENDING, /* Query is pending */ 109 EC_FLAGS_QUERY_GUARDING, /* Guard for SCI_EVT check */ 110 EC_FLAGS_GPE_HANDLER_INSTALLED, /* GPE handler installed */ 111 EC_FLAGS_EC_HANDLER_INSTALLED, /* OpReg handler installed */ 112 EC_FLAGS_EVT_HANDLER_INSTALLED, /* _Qxx handlers installed */ 113 EC_FLAGS_STARTED, /* Driver is started */ 114 EC_FLAGS_STOPPED, /* Driver is stopped */ 115 EC_FLAGS_GPE_MASKED, /* GPE masked */ 116 }; 117 118 #define ACPI_EC_COMMAND_POLL 0x01 /* Available for command byte */ 119 #define ACPI_EC_COMMAND_COMPLETE 0x02 /* Completed last byte */ 120 121 /* ec.c is compiled in acpi namespace so this shows up as acpi.ec_delay param */ 122 static unsigned int ec_delay __read_mostly = ACPI_EC_DELAY; 123 module_param(ec_delay, uint, 0644); 124 MODULE_PARM_DESC(ec_delay, "Timeout(ms) waited until an EC command completes"); 125 126 static unsigned int ec_max_queries __read_mostly = ACPI_EC_MAX_QUERIES; 127 module_param(ec_max_queries, uint, 0644); 128 MODULE_PARM_DESC(ec_max_queries, "Maximum parallel _Qxx evaluations"); 129 130 static bool ec_busy_polling __read_mostly; 131 module_param(ec_busy_polling, bool, 0644); 132 MODULE_PARM_DESC(ec_busy_polling, "Use busy polling to advance EC transaction"); 133 134 static unsigned int ec_polling_guard __read_mostly = ACPI_EC_UDELAY_POLL; 135 module_param(ec_polling_guard, uint, 0644); 136 MODULE_PARM_DESC(ec_polling_guard, "Guard time(us) between EC accesses in polling modes"); 137 138 static unsigned int ec_event_clearing __read_mostly = ACPI_EC_EVT_TIMING_QUERY; 139 140 /* 141 * If the number of false interrupts per one transaction exceeds 142 * this threshold, will think there is a GPE storm happened and 143 * will disable the GPE for normal transaction. 144 */ 145 static unsigned int ec_storm_threshold __read_mostly = 8; 146 module_param(ec_storm_threshold, uint, 0644); 147 MODULE_PARM_DESC(ec_storm_threshold, "Maxim false GPE numbers not considered as GPE storm"); 148 149 static bool ec_freeze_events __read_mostly = false; 150 module_param(ec_freeze_events, bool, 0644); 151 MODULE_PARM_DESC(ec_freeze_events, "Disabling event handling during suspend/resume"); 152 153 static bool ec_no_wakeup __read_mostly; 154 module_param(ec_no_wakeup, bool, 0644); 155 MODULE_PARM_DESC(ec_no_wakeup, "Do not wake up from suspend-to-idle"); 156 157 struct acpi_ec_query_handler { 158 struct list_head node; 159 acpi_ec_query_func func; 160 acpi_handle handle; 161 void *data; 162 u8 query_bit; 163 struct kref kref; 164 }; 165 166 struct transaction { 167 const u8 *wdata; 168 u8 *rdata; 169 unsigned short irq_count; 170 u8 command; 171 u8 wi; 172 u8 ri; 173 u8 wlen; 174 u8 rlen; 175 u8 flags; 176 }; 177 178 struct acpi_ec_query { 179 struct transaction transaction; 180 struct work_struct work; 181 struct acpi_ec_query_handler *handler; 182 }; 183 184 static int acpi_ec_query(struct acpi_ec *ec, u8 *data); 185 static void advance_transaction(struct acpi_ec *ec); 186 static void acpi_ec_event_handler(struct work_struct *work); 187 static void acpi_ec_event_processor(struct work_struct *work); 188 189 struct acpi_ec *first_ec; 190 EXPORT_SYMBOL(first_ec); 191 192 static struct acpi_ec *boot_ec; 193 static bool boot_ec_is_ecdt = false; 194 static struct workqueue_struct *ec_query_wq; 195 196 static int EC_FLAGS_QUERY_HANDSHAKE; /* Needs QR_EC issued when SCI_EVT set */ 197 static int EC_FLAGS_CORRECT_ECDT; /* Needs ECDT port address correction */ 198 static int EC_FLAGS_IGNORE_DSDT_GPE; /* Needs ECDT GPE as correction setting */ 199 static int EC_FLAGS_CLEAR_ON_RESUME; /* Needs acpi_ec_clear() on boot/resume */ 200 201 /* -------------------------------------------------------------------------- 202 * Logging/Debugging 203 * -------------------------------------------------------------------------- */ 204 205 /* 206 * Splitters used by the developers to track the boundary of the EC 207 * handling processes. 208 */ 209 #ifdef DEBUG 210 #define EC_DBG_SEP " " 211 #define EC_DBG_DRV "+++++" 212 #define EC_DBG_STM "=====" 213 #define EC_DBG_REQ "*****" 214 #define EC_DBG_EVT "#####" 215 #else 216 #define EC_DBG_SEP "" 217 #define EC_DBG_DRV 218 #define EC_DBG_STM 219 #define EC_DBG_REQ 220 #define EC_DBG_EVT 221 #endif 222 223 #define ec_log_raw(fmt, ...) \ 224 pr_info(fmt "\n", ##__VA_ARGS__) 225 #define ec_dbg_raw(fmt, ...) \ 226 pr_debug(fmt "\n", ##__VA_ARGS__) 227 #define ec_log(filter, fmt, ...) \ 228 ec_log_raw(filter EC_DBG_SEP fmt EC_DBG_SEP filter, ##__VA_ARGS__) 229 #define ec_dbg(filter, fmt, ...) \ 230 ec_dbg_raw(filter EC_DBG_SEP fmt EC_DBG_SEP filter, ##__VA_ARGS__) 231 232 #define ec_log_drv(fmt, ...) \ 233 ec_log(EC_DBG_DRV, fmt, ##__VA_ARGS__) 234 #define ec_dbg_drv(fmt, ...) \ 235 ec_dbg(EC_DBG_DRV, fmt, ##__VA_ARGS__) 236 #define ec_dbg_stm(fmt, ...) \ 237 ec_dbg(EC_DBG_STM, fmt, ##__VA_ARGS__) 238 #define ec_dbg_req(fmt, ...) \ 239 ec_dbg(EC_DBG_REQ, fmt, ##__VA_ARGS__) 240 #define ec_dbg_evt(fmt, ...) \ 241 ec_dbg(EC_DBG_EVT, fmt, ##__VA_ARGS__) 242 #define ec_dbg_ref(ec, fmt, ...) \ 243 ec_dbg_raw("%lu: " fmt, ec->reference_count, ## __VA_ARGS__) 244 245 /* -------------------------------------------------------------------------- 246 * Device Flags 247 * -------------------------------------------------------------------------- */ 248 249 static bool acpi_ec_started(struct acpi_ec *ec) 250 { 251 return test_bit(EC_FLAGS_STARTED, &ec->flags) && 252 !test_bit(EC_FLAGS_STOPPED, &ec->flags); 253 } 254 255 static bool acpi_ec_event_enabled(struct acpi_ec *ec) 256 { 257 /* 258 * There is an OSPM early stage logic. During the early stages 259 * (boot/resume), OSPMs shouldn't enable the event handling, only 260 * the EC transactions are allowed to be performed. 261 */ 262 if (!test_bit(EC_FLAGS_QUERY_ENABLED, &ec->flags)) 263 return false; 264 /* 265 * However, disabling the event handling is experimental for late 266 * stage (suspend), and is controlled by the boot parameter of 267 * "ec_freeze_events": 268 * 1. true: The EC event handling is disabled before entering 269 * the noirq stage. 270 * 2. false: The EC event handling is automatically disabled as 271 * soon as the EC driver is stopped. 272 */ 273 if (ec_freeze_events) 274 return acpi_ec_started(ec); 275 else 276 return test_bit(EC_FLAGS_STARTED, &ec->flags); 277 } 278 279 static bool acpi_ec_flushed(struct acpi_ec *ec) 280 { 281 return ec->reference_count == 1; 282 } 283 284 /* -------------------------------------------------------------------------- 285 * EC Registers 286 * -------------------------------------------------------------------------- */ 287 288 static inline u8 acpi_ec_read_status(struct acpi_ec *ec) 289 { 290 u8 x = inb(ec->command_addr); 291 292 ec_dbg_raw("EC_SC(R) = 0x%2.2x " 293 "SCI_EVT=%d BURST=%d CMD=%d IBF=%d OBF=%d", 294 x, 295 !!(x & ACPI_EC_FLAG_SCI), 296 !!(x & ACPI_EC_FLAG_BURST), 297 !!(x & ACPI_EC_FLAG_CMD), 298 !!(x & ACPI_EC_FLAG_IBF), 299 !!(x & ACPI_EC_FLAG_OBF)); 300 return x; 301 } 302 303 static inline u8 acpi_ec_read_data(struct acpi_ec *ec) 304 { 305 u8 x = inb(ec->data_addr); 306 307 ec->timestamp = jiffies; 308 ec_dbg_raw("EC_DATA(R) = 0x%2.2x", x); 309 return x; 310 } 311 312 static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command) 313 { 314 ec_dbg_raw("EC_SC(W) = 0x%2.2x", command); 315 outb(command, ec->command_addr); 316 ec->timestamp = jiffies; 317 } 318 319 static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data) 320 { 321 ec_dbg_raw("EC_DATA(W) = 0x%2.2x", data); 322 outb(data, ec->data_addr); 323 ec->timestamp = jiffies; 324 } 325 326 #if defined(DEBUG) || defined(CONFIG_DYNAMIC_DEBUG) 327 static const char *acpi_ec_cmd_string(u8 cmd) 328 { 329 switch (cmd) { 330 case 0x80: 331 return "RD_EC"; 332 case 0x81: 333 return "WR_EC"; 334 case 0x82: 335 return "BE_EC"; 336 case 0x83: 337 return "BD_EC"; 338 case 0x84: 339 return "QR_EC"; 340 } 341 return "UNKNOWN"; 342 } 343 #else 344 #define acpi_ec_cmd_string(cmd) "UNDEF" 345 #endif 346 347 /* -------------------------------------------------------------------------- 348 * GPE Registers 349 * -------------------------------------------------------------------------- */ 350 351 static inline bool acpi_ec_is_gpe_raised(struct acpi_ec *ec) 352 { 353 acpi_event_status gpe_status = 0; 354 355 (void)acpi_get_gpe_status(NULL, ec->gpe, &gpe_status); 356 return (gpe_status & ACPI_EVENT_FLAG_STATUS_SET) ? true : false; 357 } 358 359 static inline void acpi_ec_enable_gpe(struct acpi_ec *ec, bool open) 360 { 361 if (open) 362 acpi_enable_gpe(NULL, ec->gpe); 363 else { 364 BUG_ON(ec->reference_count < 1); 365 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_ENABLE); 366 } 367 if (acpi_ec_is_gpe_raised(ec)) { 368 /* 369 * On some platforms, EN=1 writes cannot trigger GPE. So 370 * software need to manually trigger a pseudo GPE event on 371 * EN=1 writes. 372 */ 373 ec_dbg_raw("Polling quirk"); 374 advance_transaction(ec); 375 } 376 } 377 378 static inline void acpi_ec_disable_gpe(struct acpi_ec *ec, bool close) 379 { 380 if (close) 381 acpi_disable_gpe(NULL, ec->gpe); 382 else { 383 BUG_ON(ec->reference_count < 1); 384 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_DISABLE); 385 } 386 } 387 388 static inline void acpi_ec_clear_gpe(struct acpi_ec *ec) 389 { 390 /* 391 * GPE STS is a W1C register, which means: 392 * 1. Software can clear it without worrying about clearing other 393 * GPEs' STS bits when the hardware sets them in parallel. 394 * 2. As long as software can ensure only clearing it when it is 395 * set, hardware won't set it in parallel. 396 * So software can clear GPE in any contexts. 397 * Warning: do not move the check into advance_transaction() as the 398 * EC commands will be sent without GPE raised. 399 */ 400 if (!acpi_ec_is_gpe_raised(ec)) 401 return; 402 acpi_clear_gpe(NULL, ec->gpe); 403 } 404 405 /* -------------------------------------------------------------------------- 406 * Transaction Management 407 * -------------------------------------------------------------------------- */ 408 409 static void acpi_ec_submit_request(struct acpi_ec *ec) 410 { 411 ec->reference_count++; 412 if (test_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags) && 413 ec->reference_count == 1) 414 acpi_ec_enable_gpe(ec, true); 415 } 416 417 static void acpi_ec_complete_request(struct acpi_ec *ec) 418 { 419 bool flushed = false; 420 421 ec->reference_count--; 422 if (test_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags) && 423 ec->reference_count == 0) 424 acpi_ec_disable_gpe(ec, true); 425 flushed = acpi_ec_flushed(ec); 426 if (flushed) 427 wake_up(&ec->wait); 428 } 429 430 static void acpi_ec_mask_gpe(struct acpi_ec *ec) 431 { 432 if (!test_bit(EC_FLAGS_GPE_MASKED, &ec->flags)) { 433 acpi_ec_disable_gpe(ec, false); 434 ec_dbg_drv("Polling enabled"); 435 set_bit(EC_FLAGS_GPE_MASKED, &ec->flags); 436 } 437 } 438 439 static void acpi_ec_unmask_gpe(struct acpi_ec *ec) 440 { 441 if (test_bit(EC_FLAGS_GPE_MASKED, &ec->flags)) { 442 clear_bit(EC_FLAGS_GPE_MASKED, &ec->flags); 443 acpi_ec_enable_gpe(ec, false); 444 ec_dbg_drv("Polling disabled"); 445 } 446 } 447 448 /* 449 * acpi_ec_submit_flushable_request() - Increase the reference count unless 450 * the flush operation is not in 451 * progress 452 * @ec: the EC device 453 * 454 * This function must be used before taking a new action that should hold 455 * the reference count. If this function returns false, then the action 456 * must be discarded or it will prevent the flush operation from being 457 * completed. 458 */ 459 static bool acpi_ec_submit_flushable_request(struct acpi_ec *ec) 460 { 461 if (!acpi_ec_started(ec)) 462 return false; 463 acpi_ec_submit_request(ec); 464 return true; 465 } 466 467 static void acpi_ec_submit_query(struct acpi_ec *ec) 468 { 469 acpi_ec_mask_gpe(ec); 470 if (!acpi_ec_event_enabled(ec)) 471 return; 472 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) { 473 ec_dbg_evt("Command(%s) submitted/blocked", 474 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY)); 475 ec->nr_pending_queries++; 476 schedule_work(&ec->work); 477 } 478 } 479 480 static void acpi_ec_complete_query(struct acpi_ec *ec) 481 { 482 if (test_and_clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) 483 ec_dbg_evt("Command(%s) unblocked", 484 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY)); 485 acpi_ec_unmask_gpe(ec); 486 } 487 488 static inline void __acpi_ec_enable_event(struct acpi_ec *ec) 489 { 490 if (!test_and_set_bit(EC_FLAGS_QUERY_ENABLED, &ec->flags)) 491 ec_log_drv("event unblocked"); 492 /* 493 * Unconditionally invoke this once after enabling the event 494 * handling mechanism to detect the pending events. 495 */ 496 advance_transaction(ec); 497 } 498 499 static inline void __acpi_ec_disable_event(struct acpi_ec *ec) 500 { 501 if (test_and_clear_bit(EC_FLAGS_QUERY_ENABLED, &ec->flags)) 502 ec_log_drv("event blocked"); 503 } 504 505 /* 506 * Process _Q events that might have accumulated in the EC. 507 * Run with locked ec mutex. 508 */ 509 static void acpi_ec_clear(struct acpi_ec *ec) 510 { 511 int i, status; 512 u8 value = 0; 513 514 for (i = 0; i < ACPI_EC_CLEAR_MAX; i++) { 515 status = acpi_ec_query(ec, &value); 516 if (status || !value) 517 break; 518 } 519 if (unlikely(i == ACPI_EC_CLEAR_MAX)) 520 pr_warn("Warning: Maximum of %d stale EC events cleared\n", i); 521 else 522 pr_info("%d stale EC events cleared\n", i); 523 } 524 525 static void acpi_ec_enable_event(struct acpi_ec *ec) 526 { 527 unsigned long flags; 528 529 spin_lock_irqsave(&ec->lock, flags); 530 if (acpi_ec_started(ec)) 531 __acpi_ec_enable_event(ec); 532 spin_unlock_irqrestore(&ec->lock, flags); 533 534 /* Drain additional events if hardware requires that */ 535 if (EC_FLAGS_CLEAR_ON_RESUME) 536 acpi_ec_clear(ec); 537 } 538 539 #ifdef CONFIG_PM_SLEEP 540 static bool acpi_ec_query_flushed(struct acpi_ec *ec) 541 { 542 bool flushed; 543 unsigned long flags; 544 545 spin_lock_irqsave(&ec->lock, flags); 546 flushed = !ec->nr_pending_queries; 547 spin_unlock_irqrestore(&ec->lock, flags); 548 return flushed; 549 } 550 551 static void __acpi_ec_flush_event(struct acpi_ec *ec) 552 { 553 /* 554 * When ec_freeze_events is true, we need to flush events in 555 * the proper position before entering the noirq stage. 556 */ 557 wait_event(ec->wait, acpi_ec_query_flushed(ec)); 558 if (ec_query_wq) 559 flush_workqueue(ec_query_wq); 560 } 561 562 static void acpi_ec_disable_event(struct acpi_ec *ec) 563 { 564 unsigned long flags; 565 566 spin_lock_irqsave(&ec->lock, flags); 567 __acpi_ec_disable_event(ec); 568 spin_unlock_irqrestore(&ec->lock, flags); 569 __acpi_ec_flush_event(ec); 570 } 571 572 void acpi_ec_flush_work(void) 573 { 574 if (first_ec) 575 __acpi_ec_flush_event(first_ec); 576 577 flush_scheduled_work(); 578 } 579 #endif /* CONFIG_PM_SLEEP */ 580 581 static bool acpi_ec_guard_event(struct acpi_ec *ec) 582 { 583 bool guarded = true; 584 unsigned long flags; 585 586 spin_lock_irqsave(&ec->lock, flags); 587 /* 588 * If firmware SCI_EVT clearing timing is "event", we actually 589 * don't know when the SCI_EVT will be cleared by firmware after 590 * evaluating _Qxx, so we need to re-check SCI_EVT after waiting an 591 * acceptable period. 592 * 593 * The guarding period begins when EC_FLAGS_QUERY_PENDING is 594 * flagged, which means SCI_EVT check has just been performed. 595 * But if the current transaction is ACPI_EC_COMMAND_QUERY, the 596 * guarding should have already been performed (via 597 * EC_FLAGS_QUERY_GUARDING) and should not be applied so that the 598 * ACPI_EC_COMMAND_QUERY transaction can be transitioned into 599 * ACPI_EC_COMMAND_POLL state immediately. 600 */ 601 if (ec_event_clearing == ACPI_EC_EVT_TIMING_STATUS || 602 ec_event_clearing == ACPI_EC_EVT_TIMING_QUERY || 603 !test_bit(EC_FLAGS_QUERY_PENDING, &ec->flags) || 604 (ec->curr && ec->curr->command == ACPI_EC_COMMAND_QUERY)) 605 guarded = false; 606 spin_unlock_irqrestore(&ec->lock, flags); 607 return guarded; 608 } 609 610 static int ec_transaction_polled(struct acpi_ec *ec) 611 { 612 unsigned long flags; 613 int ret = 0; 614 615 spin_lock_irqsave(&ec->lock, flags); 616 if (ec->curr && (ec->curr->flags & ACPI_EC_COMMAND_POLL)) 617 ret = 1; 618 spin_unlock_irqrestore(&ec->lock, flags); 619 return ret; 620 } 621 622 static int ec_transaction_completed(struct acpi_ec *ec) 623 { 624 unsigned long flags; 625 int ret = 0; 626 627 spin_lock_irqsave(&ec->lock, flags); 628 if (ec->curr && (ec->curr->flags & ACPI_EC_COMMAND_COMPLETE)) 629 ret = 1; 630 spin_unlock_irqrestore(&ec->lock, flags); 631 return ret; 632 } 633 634 static inline void ec_transaction_transition(struct acpi_ec *ec, unsigned long flag) 635 { 636 ec->curr->flags |= flag; 637 if (ec->curr->command == ACPI_EC_COMMAND_QUERY) { 638 if (ec_event_clearing == ACPI_EC_EVT_TIMING_STATUS && 639 flag == ACPI_EC_COMMAND_POLL) 640 acpi_ec_complete_query(ec); 641 if (ec_event_clearing == ACPI_EC_EVT_TIMING_QUERY && 642 flag == ACPI_EC_COMMAND_COMPLETE) 643 acpi_ec_complete_query(ec); 644 if (ec_event_clearing == ACPI_EC_EVT_TIMING_EVENT && 645 flag == ACPI_EC_COMMAND_COMPLETE) 646 set_bit(EC_FLAGS_QUERY_GUARDING, &ec->flags); 647 } 648 } 649 650 static void advance_transaction(struct acpi_ec *ec) 651 { 652 struct transaction *t; 653 u8 status; 654 bool wakeup = false; 655 656 ec_dbg_stm("%s (%d)", in_interrupt() ? "IRQ" : "TASK", 657 smp_processor_id()); 658 /* 659 * By always clearing STS before handling all indications, we can 660 * ensure a hardware STS 0->1 change after this clearing can always 661 * trigger a GPE interrupt. 662 */ 663 acpi_ec_clear_gpe(ec); 664 status = acpi_ec_read_status(ec); 665 t = ec->curr; 666 /* 667 * Another IRQ or a guarded polling mode advancement is detected, 668 * the next QR_EC submission is then allowed. 669 */ 670 if (!t || !(t->flags & ACPI_EC_COMMAND_POLL)) { 671 if (ec_event_clearing == ACPI_EC_EVT_TIMING_EVENT && 672 (!ec->nr_pending_queries || 673 test_bit(EC_FLAGS_QUERY_GUARDING, &ec->flags))) { 674 clear_bit(EC_FLAGS_QUERY_GUARDING, &ec->flags); 675 acpi_ec_complete_query(ec); 676 } 677 } 678 if (!t) 679 goto err; 680 if (t->flags & ACPI_EC_COMMAND_POLL) { 681 if (t->wlen > t->wi) { 682 if ((status & ACPI_EC_FLAG_IBF) == 0) 683 acpi_ec_write_data(ec, t->wdata[t->wi++]); 684 else 685 goto err; 686 } else if (t->rlen > t->ri) { 687 if ((status & ACPI_EC_FLAG_OBF) == 1) { 688 t->rdata[t->ri++] = acpi_ec_read_data(ec); 689 if (t->rlen == t->ri) { 690 ec_transaction_transition(ec, ACPI_EC_COMMAND_COMPLETE); 691 if (t->command == ACPI_EC_COMMAND_QUERY) 692 ec_dbg_evt("Command(%s) completed by hardware", 693 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY)); 694 wakeup = true; 695 } 696 } else 697 goto err; 698 } else if (t->wlen == t->wi && 699 (status & ACPI_EC_FLAG_IBF) == 0) { 700 ec_transaction_transition(ec, ACPI_EC_COMMAND_COMPLETE); 701 wakeup = true; 702 } 703 goto out; 704 } else { 705 if (EC_FLAGS_QUERY_HANDSHAKE && 706 !(status & ACPI_EC_FLAG_SCI) && 707 (t->command == ACPI_EC_COMMAND_QUERY)) { 708 ec_transaction_transition(ec, ACPI_EC_COMMAND_POLL); 709 t->rdata[t->ri++] = 0x00; 710 ec_transaction_transition(ec, ACPI_EC_COMMAND_COMPLETE); 711 ec_dbg_evt("Command(%s) completed by software", 712 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY)); 713 wakeup = true; 714 } else if ((status & ACPI_EC_FLAG_IBF) == 0) { 715 acpi_ec_write_cmd(ec, t->command); 716 ec_transaction_transition(ec, ACPI_EC_COMMAND_POLL); 717 } else 718 goto err; 719 goto out; 720 } 721 err: 722 /* 723 * If SCI bit is set, then don't think it's a false IRQ 724 * otherwise will take a not handled IRQ as a false one. 725 */ 726 if (!(status & ACPI_EC_FLAG_SCI)) { 727 if (in_interrupt() && t) { 728 if (t->irq_count < ec_storm_threshold) 729 ++t->irq_count; 730 /* Allow triggering on 0 threshold */ 731 if (t->irq_count == ec_storm_threshold) 732 acpi_ec_mask_gpe(ec); 733 } 734 } 735 out: 736 if (status & ACPI_EC_FLAG_SCI) 737 acpi_ec_submit_query(ec); 738 if (wakeup && in_interrupt()) 739 wake_up(&ec->wait); 740 } 741 742 static void start_transaction(struct acpi_ec *ec) 743 { 744 ec->curr->irq_count = ec->curr->wi = ec->curr->ri = 0; 745 ec->curr->flags = 0; 746 } 747 748 static int ec_guard(struct acpi_ec *ec) 749 { 750 unsigned long guard = usecs_to_jiffies(ec->polling_guard); 751 unsigned long timeout = ec->timestamp + guard; 752 753 /* Ensure guarding period before polling EC status */ 754 do { 755 if (ec->busy_polling) { 756 /* Perform busy polling */ 757 if (ec_transaction_completed(ec)) 758 return 0; 759 udelay(jiffies_to_usecs(guard)); 760 } else { 761 /* 762 * Perform wait polling 763 * 1. Wait the transaction to be completed by the 764 * GPE handler after the transaction enters 765 * ACPI_EC_COMMAND_POLL state. 766 * 2. A special guarding logic is also required 767 * for event clearing mode "event" before the 768 * transaction enters ACPI_EC_COMMAND_POLL 769 * state. 770 */ 771 if (!ec_transaction_polled(ec) && 772 !acpi_ec_guard_event(ec)) 773 break; 774 if (wait_event_timeout(ec->wait, 775 ec_transaction_completed(ec), 776 guard)) 777 return 0; 778 } 779 } while (time_before(jiffies, timeout)); 780 return -ETIME; 781 } 782 783 static int ec_poll(struct acpi_ec *ec) 784 { 785 unsigned long flags; 786 int repeat = 5; /* number of command restarts */ 787 788 while (repeat--) { 789 unsigned long delay = jiffies + 790 msecs_to_jiffies(ec_delay); 791 do { 792 if (!ec_guard(ec)) 793 return 0; 794 spin_lock_irqsave(&ec->lock, flags); 795 advance_transaction(ec); 796 spin_unlock_irqrestore(&ec->lock, flags); 797 } while (time_before(jiffies, delay)); 798 pr_debug("controller reset, restart transaction\n"); 799 spin_lock_irqsave(&ec->lock, flags); 800 start_transaction(ec); 801 spin_unlock_irqrestore(&ec->lock, flags); 802 } 803 return -ETIME; 804 } 805 806 static int acpi_ec_transaction_unlocked(struct acpi_ec *ec, 807 struct transaction *t) 808 { 809 unsigned long tmp; 810 int ret = 0; 811 812 /* start transaction */ 813 spin_lock_irqsave(&ec->lock, tmp); 814 /* Enable GPE for command processing (IBF=0/OBF=1) */ 815 if (!acpi_ec_submit_flushable_request(ec)) { 816 ret = -EINVAL; 817 goto unlock; 818 } 819 ec_dbg_ref(ec, "Increase command"); 820 /* following two actions should be kept atomic */ 821 ec->curr = t; 822 ec_dbg_req("Command(%s) started", acpi_ec_cmd_string(t->command)); 823 start_transaction(ec); 824 spin_unlock_irqrestore(&ec->lock, tmp); 825 826 ret = ec_poll(ec); 827 828 spin_lock_irqsave(&ec->lock, tmp); 829 if (t->irq_count == ec_storm_threshold) 830 acpi_ec_unmask_gpe(ec); 831 ec_dbg_req("Command(%s) stopped", acpi_ec_cmd_string(t->command)); 832 ec->curr = NULL; 833 /* Disable GPE for command processing (IBF=0/OBF=1) */ 834 acpi_ec_complete_request(ec); 835 ec_dbg_ref(ec, "Decrease command"); 836 unlock: 837 spin_unlock_irqrestore(&ec->lock, tmp); 838 return ret; 839 } 840 841 static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t) 842 { 843 int status; 844 u32 glk; 845 846 if (!ec || (!t) || (t->wlen && !t->wdata) || (t->rlen && !t->rdata)) 847 return -EINVAL; 848 if (t->rdata) 849 memset(t->rdata, 0, t->rlen); 850 851 mutex_lock(&ec->mutex); 852 if (ec->global_lock) { 853 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk); 854 if (ACPI_FAILURE(status)) { 855 status = -ENODEV; 856 goto unlock; 857 } 858 } 859 860 status = acpi_ec_transaction_unlocked(ec, t); 861 862 if (ec->global_lock) 863 acpi_release_global_lock(glk); 864 unlock: 865 mutex_unlock(&ec->mutex); 866 return status; 867 } 868 869 static int acpi_ec_burst_enable(struct acpi_ec *ec) 870 { 871 u8 d; 872 struct transaction t = {.command = ACPI_EC_BURST_ENABLE, 873 .wdata = NULL, .rdata = &d, 874 .wlen = 0, .rlen = 1}; 875 876 return acpi_ec_transaction(ec, &t); 877 } 878 879 static int acpi_ec_burst_disable(struct acpi_ec *ec) 880 { 881 struct transaction t = {.command = ACPI_EC_BURST_DISABLE, 882 .wdata = NULL, .rdata = NULL, 883 .wlen = 0, .rlen = 0}; 884 885 return (acpi_ec_read_status(ec) & ACPI_EC_FLAG_BURST) ? 886 acpi_ec_transaction(ec, &t) : 0; 887 } 888 889 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 *data) 890 { 891 int result; 892 u8 d; 893 struct transaction t = {.command = ACPI_EC_COMMAND_READ, 894 .wdata = &address, .rdata = &d, 895 .wlen = 1, .rlen = 1}; 896 897 result = acpi_ec_transaction(ec, &t); 898 *data = d; 899 return result; 900 } 901 902 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data) 903 { 904 u8 wdata[2] = { address, data }; 905 struct transaction t = {.command = ACPI_EC_COMMAND_WRITE, 906 .wdata = wdata, .rdata = NULL, 907 .wlen = 2, .rlen = 0}; 908 909 return acpi_ec_transaction(ec, &t); 910 } 911 912 int ec_read(u8 addr, u8 *val) 913 { 914 int err; 915 u8 temp_data; 916 917 if (!first_ec) 918 return -ENODEV; 919 920 err = acpi_ec_read(first_ec, addr, &temp_data); 921 922 if (!err) { 923 *val = temp_data; 924 return 0; 925 } 926 return err; 927 } 928 EXPORT_SYMBOL(ec_read); 929 930 int ec_write(u8 addr, u8 val) 931 { 932 int err; 933 934 if (!first_ec) 935 return -ENODEV; 936 937 err = acpi_ec_write(first_ec, addr, val); 938 939 return err; 940 } 941 EXPORT_SYMBOL(ec_write); 942 943 int ec_transaction(u8 command, 944 const u8 *wdata, unsigned wdata_len, 945 u8 *rdata, unsigned rdata_len) 946 { 947 struct transaction t = {.command = command, 948 .wdata = wdata, .rdata = rdata, 949 .wlen = wdata_len, .rlen = rdata_len}; 950 951 if (!first_ec) 952 return -ENODEV; 953 954 return acpi_ec_transaction(first_ec, &t); 955 } 956 EXPORT_SYMBOL(ec_transaction); 957 958 /* Get the handle to the EC device */ 959 acpi_handle ec_get_handle(void) 960 { 961 if (!first_ec) 962 return NULL; 963 return first_ec->handle; 964 } 965 EXPORT_SYMBOL(ec_get_handle); 966 967 static void acpi_ec_start(struct acpi_ec *ec, bool resuming) 968 { 969 unsigned long flags; 970 971 spin_lock_irqsave(&ec->lock, flags); 972 if (!test_and_set_bit(EC_FLAGS_STARTED, &ec->flags)) { 973 ec_dbg_drv("Starting EC"); 974 /* Enable GPE for event processing (SCI_EVT=1) */ 975 if (!resuming) { 976 acpi_ec_submit_request(ec); 977 ec_dbg_ref(ec, "Increase driver"); 978 } 979 ec_log_drv("EC started"); 980 } 981 spin_unlock_irqrestore(&ec->lock, flags); 982 } 983 984 static bool acpi_ec_stopped(struct acpi_ec *ec) 985 { 986 unsigned long flags; 987 bool flushed; 988 989 spin_lock_irqsave(&ec->lock, flags); 990 flushed = acpi_ec_flushed(ec); 991 spin_unlock_irqrestore(&ec->lock, flags); 992 return flushed; 993 } 994 995 static void acpi_ec_stop(struct acpi_ec *ec, bool suspending) 996 { 997 unsigned long flags; 998 999 spin_lock_irqsave(&ec->lock, flags); 1000 if (acpi_ec_started(ec)) { 1001 ec_dbg_drv("Stopping EC"); 1002 set_bit(EC_FLAGS_STOPPED, &ec->flags); 1003 spin_unlock_irqrestore(&ec->lock, flags); 1004 wait_event(ec->wait, acpi_ec_stopped(ec)); 1005 spin_lock_irqsave(&ec->lock, flags); 1006 /* Disable GPE for event processing (SCI_EVT=1) */ 1007 if (!suspending) { 1008 acpi_ec_complete_request(ec); 1009 ec_dbg_ref(ec, "Decrease driver"); 1010 } else if (!ec_freeze_events) 1011 __acpi_ec_disable_event(ec); 1012 clear_bit(EC_FLAGS_STARTED, &ec->flags); 1013 clear_bit(EC_FLAGS_STOPPED, &ec->flags); 1014 ec_log_drv("EC stopped"); 1015 } 1016 spin_unlock_irqrestore(&ec->lock, flags); 1017 } 1018 1019 static void acpi_ec_enter_noirq(struct acpi_ec *ec) 1020 { 1021 unsigned long flags; 1022 1023 spin_lock_irqsave(&ec->lock, flags); 1024 ec->busy_polling = true; 1025 ec->polling_guard = 0; 1026 ec_log_drv("interrupt blocked"); 1027 spin_unlock_irqrestore(&ec->lock, flags); 1028 } 1029 1030 static void acpi_ec_leave_noirq(struct acpi_ec *ec) 1031 { 1032 unsigned long flags; 1033 1034 spin_lock_irqsave(&ec->lock, flags); 1035 ec->busy_polling = ec_busy_polling; 1036 ec->polling_guard = ec_polling_guard; 1037 ec_log_drv("interrupt unblocked"); 1038 spin_unlock_irqrestore(&ec->lock, flags); 1039 } 1040 1041 void acpi_ec_block_transactions(void) 1042 { 1043 struct acpi_ec *ec = first_ec; 1044 1045 if (!ec) 1046 return; 1047 1048 mutex_lock(&ec->mutex); 1049 /* Prevent transactions from being carried out */ 1050 acpi_ec_stop(ec, true); 1051 mutex_unlock(&ec->mutex); 1052 } 1053 1054 void acpi_ec_unblock_transactions(void) 1055 { 1056 /* 1057 * Allow transactions to happen again (this function is called from 1058 * atomic context during wakeup, so we don't need to acquire the mutex). 1059 */ 1060 if (first_ec) 1061 acpi_ec_start(first_ec, true); 1062 } 1063 1064 void acpi_ec_mark_gpe_for_wake(void) 1065 { 1066 if (first_ec && !ec_no_wakeup) 1067 acpi_mark_gpe_for_wake(NULL, first_ec->gpe); 1068 } 1069 1070 void acpi_ec_set_gpe_wake_mask(u8 action) 1071 { 1072 if (first_ec && !ec_no_wakeup) 1073 acpi_set_gpe_wake_mask(NULL, first_ec->gpe, action); 1074 } 1075 1076 void acpi_ec_dispatch_gpe(void) 1077 { 1078 if (first_ec) 1079 acpi_dispatch_gpe(NULL, first_ec->gpe); 1080 } 1081 1082 /* -------------------------------------------------------------------------- 1083 Event Management 1084 -------------------------------------------------------------------------- */ 1085 static struct acpi_ec_query_handler * 1086 acpi_ec_get_query_handler(struct acpi_ec_query_handler *handler) 1087 { 1088 if (handler) 1089 kref_get(&handler->kref); 1090 return handler; 1091 } 1092 1093 static struct acpi_ec_query_handler * 1094 acpi_ec_get_query_handler_by_value(struct acpi_ec *ec, u8 value) 1095 { 1096 struct acpi_ec_query_handler *handler; 1097 bool found = false; 1098 1099 mutex_lock(&ec->mutex); 1100 list_for_each_entry(handler, &ec->list, node) { 1101 if (value == handler->query_bit) { 1102 found = true; 1103 break; 1104 } 1105 } 1106 mutex_unlock(&ec->mutex); 1107 return found ? acpi_ec_get_query_handler(handler) : NULL; 1108 } 1109 1110 static void acpi_ec_query_handler_release(struct kref *kref) 1111 { 1112 struct acpi_ec_query_handler *handler = 1113 container_of(kref, struct acpi_ec_query_handler, kref); 1114 1115 kfree(handler); 1116 } 1117 1118 static void acpi_ec_put_query_handler(struct acpi_ec_query_handler *handler) 1119 { 1120 kref_put(&handler->kref, acpi_ec_query_handler_release); 1121 } 1122 1123 int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit, 1124 acpi_handle handle, acpi_ec_query_func func, 1125 void *data) 1126 { 1127 struct acpi_ec_query_handler *handler = 1128 kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL); 1129 1130 if (!handler) 1131 return -ENOMEM; 1132 1133 handler->query_bit = query_bit; 1134 handler->handle = handle; 1135 handler->func = func; 1136 handler->data = data; 1137 mutex_lock(&ec->mutex); 1138 kref_init(&handler->kref); 1139 list_add(&handler->node, &ec->list); 1140 mutex_unlock(&ec->mutex); 1141 return 0; 1142 } 1143 EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler); 1144 1145 static void acpi_ec_remove_query_handlers(struct acpi_ec *ec, 1146 bool remove_all, u8 query_bit) 1147 { 1148 struct acpi_ec_query_handler *handler, *tmp; 1149 LIST_HEAD(free_list); 1150 1151 mutex_lock(&ec->mutex); 1152 list_for_each_entry_safe(handler, tmp, &ec->list, node) { 1153 if (remove_all || query_bit == handler->query_bit) { 1154 list_del_init(&handler->node); 1155 list_add(&handler->node, &free_list); 1156 } 1157 } 1158 mutex_unlock(&ec->mutex); 1159 list_for_each_entry_safe(handler, tmp, &free_list, node) 1160 acpi_ec_put_query_handler(handler); 1161 } 1162 1163 void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit) 1164 { 1165 acpi_ec_remove_query_handlers(ec, false, query_bit); 1166 } 1167 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler); 1168 1169 static struct acpi_ec_query *acpi_ec_create_query(u8 *pval) 1170 { 1171 struct acpi_ec_query *q; 1172 struct transaction *t; 1173 1174 q = kzalloc(sizeof (struct acpi_ec_query), GFP_KERNEL); 1175 if (!q) 1176 return NULL; 1177 INIT_WORK(&q->work, acpi_ec_event_processor); 1178 t = &q->transaction; 1179 t->command = ACPI_EC_COMMAND_QUERY; 1180 t->rdata = pval; 1181 t->rlen = 1; 1182 return q; 1183 } 1184 1185 static void acpi_ec_delete_query(struct acpi_ec_query *q) 1186 { 1187 if (q) { 1188 if (q->handler) 1189 acpi_ec_put_query_handler(q->handler); 1190 kfree(q); 1191 } 1192 } 1193 1194 static void acpi_ec_event_processor(struct work_struct *work) 1195 { 1196 struct acpi_ec_query *q = container_of(work, struct acpi_ec_query, work); 1197 struct acpi_ec_query_handler *handler = q->handler; 1198 1199 ec_dbg_evt("Query(0x%02x) started", handler->query_bit); 1200 if (handler->func) 1201 handler->func(handler->data); 1202 else if (handler->handle) 1203 acpi_evaluate_object(handler->handle, NULL, NULL, NULL); 1204 ec_dbg_evt("Query(0x%02x) stopped", handler->query_bit); 1205 acpi_ec_delete_query(q); 1206 } 1207 1208 static int acpi_ec_query(struct acpi_ec *ec, u8 *data) 1209 { 1210 u8 value = 0; 1211 int result; 1212 struct acpi_ec_query *q; 1213 1214 q = acpi_ec_create_query(&value); 1215 if (!q) 1216 return -ENOMEM; 1217 1218 /* 1219 * Query the EC to find out which _Qxx method we need to evaluate. 1220 * Note that successful completion of the query causes the ACPI_EC_SCI 1221 * bit to be cleared (and thus clearing the interrupt source). 1222 */ 1223 result = acpi_ec_transaction(ec, &q->transaction); 1224 if (!value) 1225 result = -ENODATA; 1226 if (result) 1227 goto err_exit; 1228 1229 q->handler = acpi_ec_get_query_handler_by_value(ec, value); 1230 if (!q->handler) { 1231 result = -ENODATA; 1232 goto err_exit; 1233 } 1234 1235 /* 1236 * It is reported that _Qxx are evaluated in a parallel way on 1237 * Windows: 1238 * https://bugzilla.kernel.org/show_bug.cgi?id=94411 1239 * 1240 * Put this log entry before schedule_work() in order to make 1241 * it appearing before any other log entries occurred during the 1242 * work queue execution. 1243 */ 1244 ec_dbg_evt("Query(0x%02x) scheduled", value); 1245 if (!queue_work(ec_query_wq, &q->work)) { 1246 ec_dbg_evt("Query(0x%02x) overlapped", value); 1247 result = -EBUSY; 1248 } 1249 1250 err_exit: 1251 if (result) 1252 acpi_ec_delete_query(q); 1253 if (data) 1254 *data = value; 1255 return result; 1256 } 1257 1258 static void acpi_ec_check_event(struct acpi_ec *ec) 1259 { 1260 unsigned long flags; 1261 1262 if (ec_event_clearing == ACPI_EC_EVT_TIMING_EVENT) { 1263 if (ec_guard(ec)) { 1264 spin_lock_irqsave(&ec->lock, flags); 1265 /* 1266 * Take care of the SCI_EVT unless no one else is 1267 * taking care of it. 1268 */ 1269 if (!ec->curr) 1270 advance_transaction(ec); 1271 spin_unlock_irqrestore(&ec->lock, flags); 1272 } 1273 } 1274 } 1275 1276 static void acpi_ec_event_handler(struct work_struct *work) 1277 { 1278 unsigned long flags; 1279 struct acpi_ec *ec = container_of(work, struct acpi_ec, work); 1280 1281 ec_dbg_evt("Event started"); 1282 1283 spin_lock_irqsave(&ec->lock, flags); 1284 while (ec->nr_pending_queries) { 1285 spin_unlock_irqrestore(&ec->lock, flags); 1286 (void)acpi_ec_query(ec, NULL); 1287 spin_lock_irqsave(&ec->lock, flags); 1288 ec->nr_pending_queries--; 1289 /* 1290 * Before exit, make sure that this work item can be 1291 * scheduled again. There might be QR_EC failures, leaving 1292 * EC_FLAGS_QUERY_PENDING uncleared and preventing this work 1293 * item from being scheduled again. 1294 */ 1295 if (!ec->nr_pending_queries) { 1296 if (ec_event_clearing == ACPI_EC_EVT_TIMING_STATUS || 1297 ec_event_clearing == ACPI_EC_EVT_TIMING_QUERY) 1298 acpi_ec_complete_query(ec); 1299 } 1300 } 1301 spin_unlock_irqrestore(&ec->lock, flags); 1302 1303 ec_dbg_evt("Event stopped"); 1304 1305 acpi_ec_check_event(ec); 1306 } 1307 1308 static u32 acpi_ec_gpe_handler(acpi_handle gpe_device, 1309 u32 gpe_number, void *data) 1310 { 1311 unsigned long flags; 1312 struct acpi_ec *ec = data; 1313 1314 spin_lock_irqsave(&ec->lock, flags); 1315 advance_transaction(ec); 1316 spin_unlock_irqrestore(&ec->lock, flags); 1317 return ACPI_INTERRUPT_HANDLED; 1318 } 1319 1320 /* -------------------------------------------------------------------------- 1321 * Address Space Management 1322 * -------------------------------------------------------------------------- */ 1323 1324 static acpi_status 1325 acpi_ec_space_handler(u32 function, acpi_physical_address address, 1326 u32 bits, u64 *value64, 1327 void *handler_context, void *region_context) 1328 { 1329 struct acpi_ec *ec = handler_context; 1330 int result = 0, i, bytes = bits / 8; 1331 u8 *value = (u8 *)value64; 1332 1333 if ((address > 0xFF) || !value || !handler_context) 1334 return AE_BAD_PARAMETER; 1335 1336 if (function != ACPI_READ && function != ACPI_WRITE) 1337 return AE_BAD_PARAMETER; 1338 1339 if (ec->busy_polling || bits > 8) 1340 acpi_ec_burst_enable(ec); 1341 1342 for (i = 0; i < bytes; ++i, ++address, ++value) 1343 result = (function == ACPI_READ) ? 1344 acpi_ec_read(ec, address, value) : 1345 acpi_ec_write(ec, address, *value); 1346 1347 if (ec->busy_polling || bits > 8) 1348 acpi_ec_burst_disable(ec); 1349 1350 switch (result) { 1351 case -EINVAL: 1352 return AE_BAD_PARAMETER; 1353 case -ENODEV: 1354 return AE_NOT_FOUND; 1355 case -ETIME: 1356 return AE_TIME; 1357 default: 1358 return AE_OK; 1359 } 1360 } 1361 1362 /* -------------------------------------------------------------------------- 1363 * Driver Interface 1364 * -------------------------------------------------------------------------- */ 1365 1366 static acpi_status 1367 ec_parse_io_ports(struct acpi_resource *resource, void *context); 1368 1369 static void acpi_ec_free(struct acpi_ec *ec) 1370 { 1371 if (first_ec == ec) 1372 first_ec = NULL; 1373 if (boot_ec == ec) 1374 boot_ec = NULL; 1375 kfree(ec); 1376 } 1377 1378 static struct acpi_ec *acpi_ec_alloc(void) 1379 { 1380 struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL); 1381 1382 if (!ec) 1383 return NULL; 1384 mutex_init(&ec->mutex); 1385 init_waitqueue_head(&ec->wait); 1386 INIT_LIST_HEAD(&ec->list); 1387 spin_lock_init(&ec->lock); 1388 INIT_WORK(&ec->work, acpi_ec_event_handler); 1389 ec->timestamp = jiffies; 1390 ec->busy_polling = true; 1391 ec->polling_guard = 0; 1392 return ec; 1393 } 1394 1395 static acpi_status 1396 acpi_ec_register_query_methods(acpi_handle handle, u32 level, 1397 void *context, void **return_value) 1398 { 1399 char node_name[5]; 1400 struct acpi_buffer buffer = { sizeof(node_name), node_name }; 1401 struct acpi_ec *ec = context; 1402 int value = 0; 1403 acpi_status status; 1404 1405 status = acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer); 1406 1407 if (ACPI_SUCCESS(status) && sscanf(node_name, "_Q%x", &value) == 1) 1408 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL); 1409 return AE_OK; 1410 } 1411 1412 static acpi_status 1413 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval) 1414 { 1415 acpi_status status; 1416 unsigned long long tmp = 0; 1417 struct acpi_ec *ec = context; 1418 1419 /* clear addr values, ec_parse_io_ports depend on it */ 1420 ec->command_addr = ec->data_addr = 0; 1421 1422 status = acpi_walk_resources(handle, METHOD_NAME__CRS, 1423 ec_parse_io_ports, ec); 1424 if (ACPI_FAILURE(status)) 1425 return status; 1426 if (ec->data_addr == 0 || ec->command_addr == 0) 1427 return AE_OK; 1428 1429 if (boot_ec && boot_ec_is_ecdt && EC_FLAGS_IGNORE_DSDT_GPE) { 1430 /* 1431 * Always inherit the GPE number setting from the ECDT 1432 * EC. 1433 */ 1434 ec->gpe = boot_ec->gpe; 1435 } else { 1436 /* Get GPE bit assignment (EC events). */ 1437 /* TODO: Add support for _GPE returning a package */ 1438 status = acpi_evaluate_integer(handle, "_GPE", NULL, &tmp); 1439 if (ACPI_FAILURE(status)) 1440 return status; 1441 ec->gpe = tmp; 1442 } 1443 /* Use the global lock for all EC transactions? */ 1444 tmp = 0; 1445 acpi_evaluate_integer(handle, "_GLK", NULL, &tmp); 1446 ec->global_lock = tmp; 1447 ec->handle = handle; 1448 return AE_CTRL_TERMINATE; 1449 } 1450 1451 /* 1452 * Note: This function returns an error code only when the address space 1453 * handler is not installed, which means "not able to handle 1454 * transactions". 1455 */ 1456 static int ec_install_handlers(struct acpi_ec *ec, bool handle_events) 1457 { 1458 acpi_status status; 1459 1460 acpi_ec_start(ec, false); 1461 1462 if (!test_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags)) { 1463 acpi_ec_enter_noirq(ec); 1464 status = acpi_install_address_space_handler(ec->handle, 1465 ACPI_ADR_SPACE_EC, 1466 &acpi_ec_space_handler, 1467 NULL, ec); 1468 if (ACPI_FAILURE(status)) { 1469 if (status == AE_NOT_FOUND) { 1470 /* 1471 * Maybe OS fails in evaluating the _REG 1472 * object. The AE_NOT_FOUND error will be 1473 * ignored and OS * continue to initialize 1474 * EC. 1475 */ 1476 pr_err("Fail in evaluating the _REG object" 1477 " of EC device. Broken bios is suspected.\n"); 1478 } else { 1479 acpi_ec_stop(ec, false); 1480 return -ENODEV; 1481 } 1482 } 1483 set_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags); 1484 } 1485 1486 if (!handle_events) 1487 return 0; 1488 1489 if (!test_bit(EC_FLAGS_EVT_HANDLER_INSTALLED, &ec->flags)) { 1490 /* Find and register all query methods */ 1491 acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1, 1492 acpi_ec_register_query_methods, 1493 NULL, ec, NULL); 1494 set_bit(EC_FLAGS_EVT_HANDLER_INSTALLED, &ec->flags); 1495 } 1496 if (!test_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags)) { 1497 status = acpi_install_gpe_raw_handler(NULL, ec->gpe, 1498 ACPI_GPE_EDGE_TRIGGERED, 1499 &acpi_ec_gpe_handler, ec); 1500 /* This is not fatal as we can poll EC events */ 1501 if (ACPI_SUCCESS(status)) { 1502 set_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags); 1503 acpi_ec_leave_noirq(ec); 1504 if (test_bit(EC_FLAGS_STARTED, &ec->flags) && 1505 ec->reference_count >= 1) 1506 acpi_ec_enable_gpe(ec, true); 1507 } 1508 } 1509 /* EC is fully operational, allow queries */ 1510 acpi_ec_enable_event(ec); 1511 1512 return 0; 1513 } 1514 1515 static void ec_remove_handlers(struct acpi_ec *ec) 1516 { 1517 if (test_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags)) { 1518 if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle, 1519 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler))) 1520 pr_err("failed to remove space handler\n"); 1521 clear_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags); 1522 } 1523 1524 /* 1525 * Stops handling the EC transactions after removing the operation 1526 * region handler. This is required because _REG(DISCONNECT) 1527 * invoked during the removal can result in new EC transactions. 1528 * 1529 * Flushes the EC requests and thus disables the GPE before 1530 * removing the GPE handler. This is required by the current ACPICA 1531 * GPE core. ACPICA GPE core will automatically disable a GPE when 1532 * it is indicated but there is no way to handle it. So the drivers 1533 * must disable the GPEs prior to removing the GPE handlers. 1534 */ 1535 acpi_ec_stop(ec, false); 1536 1537 if (test_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags)) { 1538 if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe, 1539 &acpi_ec_gpe_handler))) 1540 pr_err("failed to remove gpe handler\n"); 1541 clear_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags); 1542 } 1543 if (test_bit(EC_FLAGS_EVT_HANDLER_INSTALLED, &ec->flags)) { 1544 acpi_ec_remove_query_handlers(ec, true, 0); 1545 clear_bit(EC_FLAGS_EVT_HANDLER_INSTALLED, &ec->flags); 1546 } 1547 } 1548 1549 static int acpi_ec_setup(struct acpi_ec *ec, bool handle_events) 1550 { 1551 int ret; 1552 1553 ret = ec_install_handlers(ec, handle_events); 1554 if (ret) 1555 return ret; 1556 1557 /* First EC capable of handling transactions */ 1558 if (!first_ec) { 1559 first_ec = ec; 1560 acpi_handle_info(first_ec->handle, "Used as first EC\n"); 1561 } 1562 1563 acpi_handle_info(ec->handle, 1564 "GPE=0x%x, EC_CMD/EC_SC=0x%lx, EC_DATA=0x%lx\n", 1565 ec->gpe, ec->command_addr, ec->data_addr); 1566 return ret; 1567 } 1568 1569 static bool acpi_ec_ecdt_get_handle(acpi_handle *phandle) 1570 { 1571 struct acpi_table_ecdt *ecdt_ptr; 1572 acpi_status status; 1573 acpi_handle handle; 1574 1575 status = acpi_get_table(ACPI_SIG_ECDT, 1, 1576 (struct acpi_table_header **)&ecdt_ptr); 1577 if (ACPI_FAILURE(status)) 1578 return false; 1579 1580 status = acpi_get_handle(NULL, ecdt_ptr->id, &handle); 1581 if (ACPI_FAILURE(status)) 1582 return false; 1583 1584 *phandle = handle; 1585 return true; 1586 } 1587 1588 static int acpi_ec_add(struct acpi_device *device) 1589 { 1590 struct acpi_ec *ec = NULL; 1591 bool dep_update = true; 1592 acpi_status status; 1593 int ret; 1594 1595 strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME); 1596 strcpy(acpi_device_class(device), ACPI_EC_CLASS); 1597 1598 if (!strcmp(acpi_device_hid(device), ACPI_ECDT_HID)) { 1599 boot_ec_is_ecdt = true; 1600 ec = boot_ec; 1601 dep_update = false; 1602 } else { 1603 ec = acpi_ec_alloc(); 1604 if (!ec) 1605 return -ENOMEM; 1606 1607 status = ec_parse_device(device->handle, 0, ec, NULL); 1608 if (status != AE_CTRL_TERMINATE) { 1609 ret = -EINVAL; 1610 goto err_alloc; 1611 } 1612 1613 if (boot_ec && ec->command_addr == boot_ec->command_addr && 1614 ec->data_addr == boot_ec->data_addr) { 1615 boot_ec_is_ecdt = false; 1616 /* 1617 * Trust PNP0C09 namespace location rather than 1618 * ECDT ID. But trust ECDT GPE rather than _GPE 1619 * because of ASUS quirks, so do not change 1620 * boot_ec->gpe to ec->gpe. 1621 */ 1622 boot_ec->handle = ec->handle; 1623 acpi_handle_debug(ec->handle, "duplicated.\n"); 1624 acpi_ec_free(ec); 1625 ec = boot_ec; 1626 } 1627 } 1628 1629 ret = acpi_ec_setup(ec, true); 1630 if (ret) 1631 goto err_query; 1632 1633 if (ec == boot_ec) 1634 acpi_handle_info(boot_ec->handle, 1635 "Boot %s EC used to handle transactions and events\n", 1636 boot_ec_is_ecdt ? "ECDT" : "DSDT"); 1637 1638 device->driver_data = ec; 1639 1640 ret = !!request_region(ec->data_addr, 1, "EC data"); 1641 WARN(!ret, "Could not request EC data io port 0x%lx", ec->data_addr); 1642 ret = !!request_region(ec->command_addr, 1, "EC cmd"); 1643 WARN(!ret, "Could not request EC cmd io port 0x%lx", ec->command_addr); 1644 1645 if (dep_update) { 1646 /* Reprobe devices depending on the EC */ 1647 acpi_walk_dep_device_list(ec->handle); 1648 } 1649 acpi_handle_debug(ec->handle, "enumerated.\n"); 1650 return 0; 1651 1652 err_query: 1653 if (ec != boot_ec) 1654 acpi_ec_remove_query_handlers(ec, true, 0); 1655 err_alloc: 1656 if (ec != boot_ec) 1657 acpi_ec_free(ec); 1658 return ret; 1659 } 1660 1661 static int acpi_ec_remove(struct acpi_device *device) 1662 { 1663 struct acpi_ec *ec; 1664 1665 if (!device) 1666 return -EINVAL; 1667 1668 ec = acpi_driver_data(device); 1669 release_region(ec->data_addr, 1); 1670 release_region(ec->command_addr, 1); 1671 device->driver_data = NULL; 1672 if (ec != boot_ec) { 1673 ec_remove_handlers(ec); 1674 acpi_ec_free(ec); 1675 } 1676 return 0; 1677 } 1678 1679 static acpi_status 1680 ec_parse_io_ports(struct acpi_resource *resource, void *context) 1681 { 1682 struct acpi_ec *ec = context; 1683 1684 if (resource->type != ACPI_RESOURCE_TYPE_IO) 1685 return AE_OK; 1686 1687 /* 1688 * The first address region returned is the data port, and 1689 * the second address region returned is the status/command 1690 * port. 1691 */ 1692 if (ec->data_addr == 0) 1693 ec->data_addr = resource->data.io.minimum; 1694 else if (ec->command_addr == 0) 1695 ec->command_addr = resource->data.io.minimum; 1696 else 1697 return AE_CTRL_TERMINATE; 1698 1699 return AE_OK; 1700 } 1701 1702 static const struct acpi_device_id ec_device_ids[] = { 1703 {"PNP0C09", 0}, 1704 {ACPI_ECDT_HID, 0}, 1705 {"", 0}, 1706 }; 1707 1708 /* 1709 * This function is not Windows-compatible as Windows never enumerates the 1710 * namespace EC before the main ACPI device enumeration process. It is 1711 * retained for historical reason and will be deprecated in the future. 1712 */ 1713 void __init acpi_ec_dsdt_probe(void) 1714 { 1715 struct acpi_ec *ec; 1716 acpi_status status; 1717 int ret; 1718 1719 /* 1720 * If a platform has ECDT, there is no need to proceed as the 1721 * following probe is not a part of the ACPI device enumeration, 1722 * executing _STA is not safe, and thus this probe may risk of 1723 * picking up an invalid EC device. 1724 */ 1725 if (boot_ec) 1726 return; 1727 1728 ec = acpi_ec_alloc(); 1729 if (!ec) 1730 return; 1731 1732 /* 1733 * At this point, the namespace is initialized, so start to find 1734 * the namespace objects. 1735 */ 1736 status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device, ec, NULL); 1737 if (ACPI_FAILURE(status) || !ec->handle) { 1738 acpi_ec_free(ec); 1739 return; 1740 } 1741 1742 /* 1743 * When the DSDT EC is available, always re-configure boot EC to 1744 * have _REG evaluated. _REG can only be evaluated after the 1745 * namespace initialization. 1746 * At this point, the GPE is not fully initialized, so do not to 1747 * handle the events. 1748 */ 1749 ret = acpi_ec_setup(ec, false); 1750 if (ret) { 1751 acpi_ec_free(ec); 1752 return; 1753 } 1754 1755 boot_ec = ec; 1756 1757 acpi_handle_info(ec->handle, 1758 "Boot DSDT EC used to handle transactions\n"); 1759 } 1760 1761 /* 1762 * If the DSDT EC is not functioning, we still need to prepare a fully 1763 * functioning ECDT EC first in order to handle the events. 1764 * https://bugzilla.kernel.org/show_bug.cgi?id=115021 1765 */ 1766 static int __init acpi_ec_ecdt_start(void) 1767 { 1768 acpi_handle handle; 1769 1770 if (!boot_ec) 1771 return -ENODEV; 1772 /* In case acpi_ec_ecdt_start() is called after acpi_ec_add() */ 1773 if (!boot_ec_is_ecdt) 1774 return -ENODEV; 1775 1776 /* 1777 * At this point, the namespace and the GPE is initialized, so 1778 * start to find the namespace objects and handle the events. 1779 * 1780 * Note: ec->handle can be valid if this function is called after 1781 * acpi_ec_add(), hence the fast path. 1782 */ 1783 if (boot_ec->handle == ACPI_ROOT_OBJECT) { 1784 if (!acpi_ec_ecdt_get_handle(&handle)) 1785 return -ENODEV; 1786 boot_ec->handle = handle; 1787 } 1788 1789 /* Register to ACPI bus with PM ops attached */ 1790 return acpi_bus_register_early_device(ACPI_BUS_TYPE_ECDT_EC); 1791 } 1792 1793 #if 0 1794 /* 1795 * Some EC firmware variations refuses to respond QR_EC when SCI_EVT is not 1796 * set, for which case, we complete the QR_EC without issuing it to the 1797 * firmware. 1798 * https://bugzilla.kernel.org/show_bug.cgi?id=82611 1799 * https://bugzilla.kernel.org/show_bug.cgi?id=97381 1800 */ 1801 static int ec_flag_query_handshake(const struct dmi_system_id *id) 1802 { 1803 pr_debug("Detected the EC firmware requiring QR_EC issued when SCI_EVT set\n"); 1804 EC_FLAGS_QUERY_HANDSHAKE = 1; 1805 return 0; 1806 } 1807 #endif 1808 1809 /* 1810 * On some hardware it is necessary to clear events accumulated by the EC during 1811 * sleep. These ECs stop reporting GPEs until they are manually polled, if too 1812 * many events are accumulated. (e.g. Samsung Series 5/9 notebooks) 1813 * 1814 * https://bugzilla.kernel.org/show_bug.cgi?id=44161 1815 * 1816 * Ideally, the EC should also be instructed NOT to accumulate events during 1817 * sleep (which Windows seems to do somehow), but the interface to control this 1818 * behaviour is not known at this time. 1819 * 1820 * Models known to be affected are Samsung 530Uxx/535Uxx/540Uxx/550Pxx/900Xxx, 1821 * however it is very likely that other Samsung models are affected. 1822 * 1823 * On systems which don't accumulate _Q events during sleep, this extra check 1824 * should be harmless. 1825 */ 1826 static int ec_clear_on_resume(const struct dmi_system_id *id) 1827 { 1828 pr_debug("Detected system needing EC poll on resume.\n"); 1829 EC_FLAGS_CLEAR_ON_RESUME = 1; 1830 ec_event_clearing = ACPI_EC_EVT_TIMING_STATUS; 1831 return 0; 1832 } 1833 1834 /* 1835 * Some ECDTs contain wrong register addresses. 1836 * MSI MS-171F 1837 * https://bugzilla.kernel.org/show_bug.cgi?id=12461 1838 */ 1839 static int ec_correct_ecdt(const struct dmi_system_id *id) 1840 { 1841 pr_debug("Detected system needing ECDT address correction.\n"); 1842 EC_FLAGS_CORRECT_ECDT = 1; 1843 return 0; 1844 } 1845 1846 /* 1847 * Some DSDTs contain wrong GPE setting. 1848 * Asus FX502VD/VE, GL702VMK, X550VXK, X580VD 1849 * https://bugzilla.kernel.org/show_bug.cgi?id=195651 1850 */ 1851 static int ec_honor_ecdt_gpe(const struct dmi_system_id *id) 1852 { 1853 pr_debug("Detected system needing ignore DSDT GPE setting.\n"); 1854 EC_FLAGS_IGNORE_DSDT_GPE = 1; 1855 return 0; 1856 } 1857 1858 static const struct dmi_system_id ec_dmi_table[] __initconst = { 1859 { 1860 ec_correct_ecdt, "MSI MS-171F", { 1861 DMI_MATCH(DMI_SYS_VENDOR, "Micro-Star"), 1862 DMI_MATCH(DMI_PRODUCT_NAME, "MS-171F"),}, NULL}, 1863 { 1864 ec_honor_ecdt_gpe, "ASUS FX502VD", { 1865 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."), 1866 DMI_MATCH(DMI_PRODUCT_NAME, "FX502VD"),}, NULL}, 1867 { 1868 ec_honor_ecdt_gpe, "ASUS FX502VE", { 1869 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."), 1870 DMI_MATCH(DMI_PRODUCT_NAME, "FX502VE"),}, NULL}, 1871 { 1872 ec_honor_ecdt_gpe, "ASUS GL702VMK", { 1873 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."), 1874 DMI_MATCH(DMI_PRODUCT_NAME, "GL702VMK"),}, NULL}, 1875 { 1876 ec_honor_ecdt_gpe, "ASUS X550VXK", { 1877 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."), 1878 DMI_MATCH(DMI_PRODUCT_NAME, "X550VXK"),}, NULL}, 1879 { 1880 ec_honor_ecdt_gpe, "ASUS X580VD", { 1881 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."), 1882 DMI_MATCH(DMI_PRODUCT_NAME, "X580VD"),}, NULL}, 1883 { 1884 ec_clear_on_resume, "Samsung hardware", { 1885 DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD.")}, NULL}, 1886 {}, 1887 }; 1888 1889 void __init acpi_ec_ecdt_probe(void) 1890 { 1891 struct acpi_table_ecdt *ecdt_ptr; 1892 struct acpi_ec *ec; 1893 acpi_status status; 1894 int ret; 1895 1896 /* Generate a boot ec context. */ 1897 dmi_check_system(ec_dmi_table); 1898 status = acpi_get_table(ACPI_SIG_ECDT, 1, 1899 (struct acpi_table_header **)&ecdt_ptr); 1900 if (ACPI_FAILURE(status)) 1901 return; 1902 1903 if (!ecdt_ptr->control.address || !ecdt_ptr->data.address) { 1904 /* 1905 * Asus X50GL: 1906 * https://bugzilla.kernel.org/show_bug.cgi?id=11880 1907 */ 1908 return; 1909 } 1910 1911 ec = acpi_ec_alloc(); 1912 if (!ec) 1913 return; 1914 1915 if (EC_FLAGS_CORRECT_ECDT) { 1916 ec->command_addr = ecdt_ptr->data.address; 1917 ec->data_addr = ecdt_ptr->control.address; 1918 } else { 1919 ec->command_addr = ecdt_ptr->control.address; 1920 ec->data_addr = ecdt_ptr->data.address; 1921 } 1922 ec->gpe = ecdt_ptr->gpe; 1923 ec->handle = ACPI_ROOT_OBJECT; 1924 1925 /* 1926 * At this point, the namespace is not initialized, so do not find 1927 * the namespace objects, or handle the events. 1928 */ 1929 ret = acpi_ec_setup(ec, false); 1930 if (ret) { 1931 acpi_ec_free(ec); 1932 return; 1933 } 1934 1935 boot_ec = ec; 1936 boot_ec_is_ecdt = true; 1937 1938 pr_info("Boot ECDT EC used to handle transactions\n"); 1939 } 1940 1941 #ifdef CONFIG_PM_SLEEP 1942 static int acpi_ec_suspend(struct device *dev) 1943 { 1944 struct acpi_ec *ec = 1945 acpi_driver_data(to_acpi_device(dev)); 1946 1947 if (acpi_sleep_no_ec_events() && ec_freeze_events) 1948 acpi_ec_disable_event(ec); 1949 return 0; 1950 } 1951 1952 static int acpi_ec_suspend_noirq(struct device *dev) 1953 { 1954 struct acpi_ec *ec = acpi_driver_data(to_acpi_device(dev)); 1955 1956 /* 1957 * The SCI handler doesn't run at this point, so the GPE can be 1958 * masked at the low level without side effects. 1959 */ 1960 if (ec_no_wakeup && test_bit(EC_FLAGS_STARTED, &ec->flags) && 1961 ec->reference_count >= 1) 1962 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_DISABLE); 1963 1964 if (acpi_sleep_no_ec_events()) 1965 acpi_ec_enter_noirq(ec); 1966 1967 return 0; 1968 } 1969 1970 static int acpi_ec_resume_noirq(struct device *dev) 1971 { 1972 struct acpi_ec *ec = acpi_driver_data(to_acpi_device(dev)); 1973 1974 if (acpi_sleep_no_ec_events()) 1975 acpi_ec_leave_noirq(ec); 1976 1977 if (ec_no_wakeup && test_bit(EC_FLAGS_STARTED, &ec->flags) && 1978 ec->reference_count >= 1) 1979 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_ENABLE); 1980 1981 return 0; 1982 } 1983 1984 static int acpi_ec_resume(struct device *dev) 1985 { 1986 struct acpi_ec *ec = 1987 acpi_driver_data(to_acpi_device(dev)); 1988 1989 acpi_ec_enable_event(ec); 1990 return 0; 1991 } 1992 #endif 1993 1994 static const struct dev_pm_ops acpi_ec_pm = { 1995 SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(acpi_ec_suspend_noirq, acpi_ec_resume_noirq) 1996 SET_SYSTEM_SLEEP_PM_OPS(acpi_ec_suspend, acpi_ec_resume) 1997 }; 1998 1999 static int param_set_event_clearing(const char *val, 2000 const struct kernel_param *kp) 2001 { 2002 int result = 0; 2003 2004 if (!strncmp(val, "status", sizeof("status") - 1)) { 2005 ec_event_clearing = ACPI_EC_EVT_TIMING_STATUS; 2006 pr_info("Assuming SCI_EVT clearing on EC_SC accesses\n"); 2007 } else if (!strncmp(val, "query", sizeof("query") - 1)) { 2008 ec_event_clearing = ACPI_EC_EVT_TIMING_QUERY; 2009 pr_info("Assuming SCI_EVT clearing on QR_EC writes\n"); 2010 } else if (!strncmp(val, "event", sizeof("event") - 1)) { 2011 ec_event_clearing = ACPI_EC_EVT_TIMING_EVENT; 2012 pr_info("Assuming SCI_EVT clearing on event reads\n"); 2013 } else 2014 result = -EINVAL; 2015 return result; 2016 } 2017 2018 static int param_get_event_clearing(char *buffer, 2019 const struct kernel_param *kp) 2020 { 2021 switch (ec_event_clearing) { 2022 case ACPI_EC_EVT_TIMING_STATUS: 2023 return sprintf(buffer, "status"); 2024 case ACPI_EC_EVT_TIMING_QUERY: 2025 return sprintf(buffer, "query"); 2026 case ACPI_EC_EVT_TIMING_EVENT: 2027 return sprintf(buffer, "event"); 2028 default: 2029 return sprintf(buffer, "invalid"); 2030 } 2031 return 0; 2032 } 2033 2034 module_param_call(ec_event_clearing, param_set_event_clearing, param_get_event_clearing, 2035 NULL, 0644); 2036 MODULE_PARM_DESC(ec_event_clearing, "Assumed SCI_EVT clearing timing"); 2037 2038 static struct acpi_driver acpi_ec_driver = { 2039 .name = "ec", 2040 .class = ACPI_EC_CLASS, 2041 .ids = ec_device_ids, 2042 .ops = { 2043 .add = acpi_ec_add, 2044 .remove = acpi_ec_remove, 2045 }, 2046 .drv.pm = &acpi_ec_pm, 2047 }; 2048 2049 static inline int acpi_ec_query_init(void) 2050 { 2051 if (!ec_query_wq) { 2052 ec_query_wq = alloc_workqueue("kec_query", 0, 2053 ec_max_queries); 2054 if (!ec_query_wq) 2055 return -ENODEV; 2056 } 2057 return 0; 2058 } 2059 2060 static inline void acpi_ec_query_exit(void) 2061 { 2062 if (ec_query_wq) { 2063 destroy_workqueue(ec_query_wq); 2064 ec_query_wq = NULL; 2065 } 2066 } 2067 2068 static const struct dmi_system_id acpi_ec_no_wakeup[] = { 2069 { 2070 .ident = "Thinkpad X1 Carbon 6th", 2071 .matches = { 2072 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"), 2073 DMI_MATCH(DMI_PRODUCT_FAMILY, "Thinkpad X1 Carbon 6th"), 2074 }, 2075 }, 2076 { 2077 .ident = "ThinkPad X1 Carbon 6th", 2078 .matches = { 2079 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"), 2080 DMI_MATCH(DMI_PRODUCT_FAMILY, "ThinkPad X1 Carbon 6th"), 2081 }, 2082 }, 2083 { 2084 .ident = "ThinkPad X1 Yoga 3rd", 2085 .matches = { 2086 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"), 2087 DMI_MATCH(DMI_PRODUCT_FAMILY, "ThinkPad X1 Yoga 3rd"), 2088 }, 2089 }, 2090 { }, 2091 }; 2092 2093 int __init acpi_ec_init(void) 2094 { 2095 int result; 2096 int ecdt_fail, dsdt_fail; 2097 2098 /* register workqueue for _Qxx evaluations */ 2099 result = acpi_ec_query_init(); 2100 if (result) 2101 return result; 2102 2103 /* 2104 * Disable EC wakeup on following systems to prevent periodic 2105 * wakeup from EC GPE. 2106 */ 2107 if (dmi_check_system(acpi_ec_no_wakeup)) { 2108 ec_no_wakeup = true; 2109 pr_debug("Disabling EC wakeup on suspend-to-idle\n"); 2110 } 2111 2112 /* Drivers must be started after acpi_ec_query_init() */ 2113 dsdt_fail = acpi_bus_register_driver(&acpi_ec_driver); 2114 /* 2115 * Register ECDT to ACPI bus only when PNP0C09 probe fails. This is 2116 * useful for platforms (confirmed on ASUS X550ZE) with valid ECDT 2117 * settings but invalid DSDT settings. 2118 * https://bugzilla.kernel.org/show_bug.cgi?id=196847 2119 */ 2120 ecdt_fail = acpi_ec_ecdt_start(); 2121 return ecdt_fail && dsdt_fail ? -ENODEV : 0; 2122 } 2123 2124 /* EC driver currently not unloadable */ 2125 #if 0 2126 static void __exit acpi_ec_exit(void) 2127 { 2128 2129 acpi_bus_unregister_driver(&acpi_ec_driver); 2130 acpi_ec_query_exit(); 2131 } 2132 #endif /* 0 */ 2133