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