1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * ec.c - ACPI Embedded Controller Driver (v3) 4 * 5 * Copyright (C) 2001-2015 Intel Corporation 6 * Author: 2014, 2015 Lv Zheng <lv.zheng@intel.com> 7 * 2006, 2007 Alexey Starikovskiy <alexey.y.starikovskiy@intel.com> 8 * 2006 Denis Sadykov <denis.m.sadykov@intel.com> 9 * 2004 Luming Yu <luming.yu@intel.com> 10 * 2001, 2002 Andy Grover <andrew.grover@intel.com> 11 * 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com> 12 * Copyright (C) 2008 Alexey Starikovskiy <astarikovskiy@suse.de> 13 */ 14 15 /* Uncomment next line to get verbose printout */ 16 /* #define DEBUG */ 17 #define pr_fmt(fmt) "ACPI: EC: " fmt 18 19 #include <linux/kernel.h> 20 #include <linux/module.h> 21 #include <linux/init.h> 22 #include <linux/types.h> 23 #include <linux/delay.h> 24 #include <linux/interrupt.h> 25 #include <linux/list.h> 26 #include <linux/spinlock.h> 27 #include <linux/slab.h> 28 #include <linux/suspend.h> 29 #include <linux/acpi.h> 30 #include <linux/dmi.h> 31 #include <asm/io.h> 32 33 #include "internal.h" 34 35 #define ACPI_EC_CLASS "embedded_controller" 36 #define ACPI_EC_DEVICE_NAME "Embedded Controller" 37 38 /* EC status register */ 39 #define ACPI_EC_FLAG_OBF 0x01 /* Output buffer full */ 40 #define ACPI_EC_FLAG_IBF 0x02 /* Input buffer full */ 41 #define ACPI_EC_FLAG_CMD 0x08 /* Input buffer contains a command */ 42 #define ACPI_EC_FLAG_BURST 0x10 /* burst mode */ 43 #define ACPI_EC_FLAG_SCI 0x20 /* EC-SCI occurred */ 44 45 /* 46 * The SCI_EVT clearing timing is not defined by the ACPI specification. 47 * This leads to lots of practical timing issues for the host EC driver. 48 * The following variations are defined (from the target EC firmware's 49 * perspective): 50 * STATUS: After indicating SCI_EVT edge triggered IRQ to the host, the 51 * target can clear SCI_EVT at any time so long as the host can see 52 * the indication by reading the status register (EC_SC). So the 53 * host should re-check SCI_EVT after the first time the SCI_EVT 54 * indication is seen, which is the same time the query request 55 * (QR_EC) is written to the command register (EC_CMD). SCI_EVT set 56 * at any later time could indicate another event. Normally such 57 * kind of EC firmware has implemented an event queue and will 58 * return 0x00 to indicate "no outstanding event". 59 * QUERY: After seeing the query request (QR_EC) written to the command 60 * register (EC_CMD) by the host and having prepared the responding 61 * event value in the data register (EC_DATA), the target can safely 62 * clear SCI_EVT because the target can confirm that the current 63 * event is being handled by the host. The host then should check 64 * SCI_EVT right after reading the event response from the data 65 * register (EC_DATA). 66 * EVENT: After seeing the event response read from the data register 67 * (EC_DATA) by the host, the target can clear SCI_EVT. As the 68 * target requires time to notice the change in the data register 69 * (EC_DATA), the host may be required to wait additional guarding 70 * time before checking the SCI_EVT again. Such guarding may not be 71 * necessary if the host is notified via another IRQ. 72 */ 73 #define ACPI_EC_EVT_TIMING_STATUS 0x00 74 #define ACPI_EC_EVT_TIMING_QUERY 0x01 75 #define ACPI_EC_EVT_TIMING_EVENT 0x02 76 77 /* EC commands */ 78 enum ec_command { 79 ACPI_EC_COMMAND_READ = 0x80, 80 ACPI_EC_COMMAND_WRITE = 0x81, 81 ACPI_EC_BURST_ENABLE = 0x82, 82 ACPI_EC_BURST_DISABLE = 0x83, 83 ACPI_EC_COMMAND_QUERY = 0x84, 84 }; 85 86 #define ACPI_EC_DELAY 500 /* Wait 500ms max. during EC ops */ 87 #define ACPI_EC_UDELAY_GLK 1000 /* Wait 1ms max. to get global lock */ 88 #define ACPI_EC_UDELAY_POLL 550 /* Wait 1ms for EC transaction polling */ 89 #define ACPI_EC_CLEAR_MAX 100 /* Maximum number of events to query 90 * when trying to clear the EC */ 91 #define ACPI_EC_MAX_QUERIES 16 /* Maximum number of parallel queries */ 92 93 enum { 94 EC_FLAGS_QUERY_ENABLED, /* Query is enabled */ 95 EC_FLAGS_QUERY_PENDING, /* Query is pending */ 96 EC_FLAGS_QUERY_GUARDING, /* Guard for SCI_EVT check */ 97 EC_FLAGS_EVENT_HANDLER_INSTALLED, /* Event handler installed */ 98 EC_FLAGS_EC_HANDLER_INSTALLED, /* OpReg handler installed */ 99 EC_FLAGS_QUERY_METHODS_INSTALLED, /* _Qxx handlers installed */ 100 EC_FLAGS_STARTED, /* Driver is started */ 101 EC_FLAGS_STOPPED, /* Driver is stopped */ 102 EC_FLAGS_EVENTS_MASKED, /* Events masked */ 103 }; 104 105 #define ACPI_EC_COMMAND_POLL 0x01 /* Available for command byte */ 106 #define ACPI_EC_COMMAND_COMPLETE 0x02 /* Completed last byte */ 107 108 /* ec.c is compiled in acpi namespace so this shows up as acpi.ec_delay param */ 109 static unsigned int ec_delay __read_mostly = ACPI_EC_DELAY; 110 module_param(ec_delay, uint, 0644); 111 MODULE_PARM_DESC(ec_delay, "Timeout(ms) waited until an EC command completes"); 112 113 static unsigned int ec_max_queries __read_mostly = ACPI_EC_MAX_QUERIES; 114 module_param(ec_max_queries, uint, 0644); 115 MODULE_PARM_DESC(ec_max_queries, "Maximum parallel _Qxx evaluations"); 116 117 static bool ec_busy_polling __read_mostly; 118 module_param(ec_busy_polling, bool, 0644); 119 MODULE_PARM_DESC(ec_busy_polling, "Use busy polling to advance EC transaction"); 120 121 static unsigned int ec_polling_guard __read_mostly = ACPI_EC_UDELAY_POLL; 122 module_param(ec_polling_guard, uint, 0644); 123 MODULE_PARM_DESC(ec_polling_guard, "Guard time(us) between EC accesses in polling modes"); 124 125 static unsigned int ec_event_clearing __read_mostly = ACPI_EC_EVT_TIMING_QUERY; 126 127 /* 128 * If the number of false interrupts per one transaction exceeds 129 * this threshold, will think there is a GPE storm happened and 130 * will disable the GPE for normal transaction. 131 */ 132 static unsigned int ec_storm_threshold __read_mostly = 8; 133 module_param(ec_storm_threshold, uint, 0644); 134 MODULE_PARM_DESC(ec_storm_threshold, "Maxim false GPE numbers not considered as GPE storm"); 135 136 static bool ec_freeze_events __read_mostly = false; 137 module_param(ec_freeze_events, bool, 0644); 138 MODULE_PARM_DESC(ec_freeze_events, "Disabling event handling during suspend/resume"); 139 140 static bool ec_no_wakeup __read_mostly; 141 module_param(ec_no_wakeup, bool, 0644); 142 MODULE_PARM_DESC(ec_no_wakeup, "Do not wake up from suspend-to-idle"); 143 144 struct acpi_ec_query_handler { 145 struct list_head node; 146 acpi_ec_query_func func; 147 acpi_handle handle; 148 void *data; 149 u8 query_bit; 150 struct kref kref; 151 }; 152 153 struct transaction { 154 const u8 *wdata; 155 u8 *rdata; 156 unsigned short irq_count; 157 u8 command; 158 u8 wi; 159 u8 ri; 160 u8 wlen; 161 u8 rlen; 162 u8 flags; 163 }; 164 165 struct acpi_ec_query { 166 struct transaction transaction; 167 struct work_struct work; 168 struct acpi_ec_query_handler *handler; 169 }; 170 171 static int acpi_ec_query(struct acpi_ec *ec, u8 *data); 172 static void advance_transaction(struct acpi_ec *ec); 173 static void acpi_ec_event_handler(struct work_struct *work); 174 static void acpi_ec_event_processor(struct work_struct *work); 175 176 struct acpi_ec *first_ec; 177 EXPORT_SYMBOL(first_ec); 178 179 static struct acpi_ec *boot_ec; 180 static bool boot_ec_is_ecdt = false; 181 static struct workqueue_struct *ec_wq; 182 static struct workqueue_struct *ec_query_wq; 183 184 static int EC_FLAGS_CORRECT_ECDT; /* Needs ECDT port address correction */ 185 static int EC_FLAGS_IGNORE_DSDT_GPE; /* Needs ECDT GPE as correction setting */ 186 static int EC_FLAGS_CLEAR_ON_RESUME; /* Needs acpi_ec_clear() on boot/resume */ 187 188 /* -------------------------------------------------------------------------- 189 * Logging/Debugging 190 * -------------------------------------------------------------------------- */ 191 192 /* 193 * Splitters used by the developers to track the boundary of the EC 194 * handling processes. 195 */ 196 #ifdef DEBUG 197 #define EC_DBG_SEP " " 198 #define EC_DBG_DRV "+++++" 199 #define EC_DBG_STM "=====" 200 #define EC_DBG_REQ "*****" 201 #define EC_DBG_EVT "#####" 202 #else 203 #define EC_DBG_SEP "" 204 #define EC_DBG_DRV 205 #define EC_DBG_STM 206 #define EC_DBG_REQ 207 #define EC_DBG_EVT 208 #endif 209 210 #define ec_log_raw(fmt, ...) \ 211 pr_info(fmt "\n", ##__VA_ARGS__) 212 #define ec_dbg_raw(fmt, ...) \ 213 pr_debug(fmt "\n", ##__VA_ARGS__) 214 #define ec_log(filter, fmt, ...) \ 215 ec_log_raw(filter EC_DBG_SEP fmt EC_DBG_SEP filter, ##__VA_ARGS__) 216 #define ec_dbg(filter, fmt, ...) \ 217 ec_dbg_raw(filter EC_DBG_SEP fmt EC_DBG_SEP filter, ##__VA_ARGS__) 218 219 #define ec_log_drv(fmt, ...) \ 220 ec_log(EC_DBG_DRV, fmt, ##__VA_ARGS__) 221 #define ec_dbg_drv(fmt, ...) \ 222 ec_dbg(EC_DBG_DRV, fmt, ##__VA_ARGS__) 223 #define ec_dbg_stm(fmt, ...) \ 224 ec_dbg(EC_DBG_STM, fmt, ##__VA_ARGS__) 225 #define ec_dbg_req(fmt, ...) \ 226 ec_dbg(EC_DBG_REQ, fmt, ##__VA_ARGS__) 227 #define ec_dbg_evt(fmt, ...) \ 228 ec_dbg(EC_DBG_EVT, fmt, ##__VA_ARGS__) 229 #define ec_dbg_ref(ec, fmt, ...) \ 230 ec_dbg_raw("%lu: " fmt, ec->reference_count, ## __VA_ARGS__) 231 232 /* -------------------------------------------------------------------------- 233 * Device Flags 234 * -------------------------------------------------------------------------- */ 235 236 static bool acpi_ec_started(struct acpi_ec *ec) 237 { 238 return test_bit(EC_FLAGS_STARTED, &ec->flags) && 239 !test_bit(EC_FLAGS_STOPPED, &ec->flags); 240 } 241 242 static bool acpi_ec_event_enabled(struct acpi_ec *ec) 243 { 244 /* 245 * There is an OSPM early stage logic. During the early stages 246 * (boot/resume), OSPMs shouldn't enable the event handling, only 247 * the EC transactions are allowed to be performed. 248 */ 249 if (!test_bit(EC_FLAGS_QUERY_ENABLED, &ec->flags)) 250 return false; 251 /* 252 * However, disabling the event handling is experimental for late 253 * stage (suspend), and is controlled by the boot parameter of 254 * "ec_freeze_events": 255 * 1. true: The EC event handling is disabled before entering 256 * the noirq stage. 257 * 2. false: The EC event handling is automatically disabled as 258 * soon as the EC driver is stopped. 259 */ 260 if (ec_freeze_events) 261 return acpi_ec_started(ec); 262 else 263 return test_bit(EC_FLAGS_STARTED, &ec->flags); 264 } 265 266 static bool acpi_ec_flushed(struct acpi_ec *ec) 267 { 268 return ec->reference_count == 1; 269 } 270 271 /* -------------------------------------------------------------------------- 272 * EC Registers 273 * -------------------------------------------------------------------------- */ 274 275 static inline u8 acpi_ec_read_status(struct acpi_ec *ec) 276 { 277 u8 x = inb(ec->command_addr); 278 279 ec_dbg_raw("EC_SC(R) = 0x%2.2x " 280 "SCI_EVT=%d BURST=%d CMD=%d IBF=%d OBF=%d", 281 x, 282 !!(x & ACPI_EC_FLAG_SCI), 283 !!(x & ACPI_EC_FLAG_BURST), 284 !!(x & ACPI_EC_FLAG_CMD), 285 !!(x & ACPI_EC_FLAG_IBF), 286 !!(x & ACPI_EC_FLAG_OBF)); 287 return x; 288 } 289 290 static inline u8 acpi_ec_read_data(struct acpi_ec *ec) 291 { 292 u8 x = inb(ec->data_addr); 293 294 ec->timestamp = jiffies; 295 ec_dbg_raw("EC_DATA(R) = 0x%2.2x", x); 296 return x; 297 } 298 299 static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command) 300 { 301 ec_dbg_raw("EC_SC(W) = 0x%2.2x", command); 302 outb(command, ec->command_addr); 303 ec->timestamp = jiffies; 304 } 305 306 static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data) 307 { 308 ec_dbg_raw("EC_DATA(W) = 0x%2.2x", data); 309 outb(data, ec->data_addr); 310 ec->timestamp = jiffies; 311 } 312 313 #if defined(DEBUG) || defined(CONFIG_DYNAMIC_DEBUG) 314 static const char *acpi_ec_cmd_string(u8 cmd) 315 { 316 switch (cmd) { 317 case 0x80: 318 return "RD_EC"; 319 case 0x81: 320 return "WR_EC"; 321 case 0x82: 322 return "BE_EC"; 323 case 0x83: 324 return "BD_EC"; 325 case 0x84: 326 return "QR_EC"; 327 } 328 return "UNKNOWN"; 329 } 330 #else 331 #define acpi_ec_cmd_string(cmd) "UNDEF" 332 #endif 333 334 /* -------------------------------------------------------------------------- 335 * GPE Registers 336 * -------------------------------------------------------------------------- */ 337 338 static inline bool acpi_ec_is_gpe_raised(struct acpi_ec *ec) 339 { 340 acpi_event_status gpe_status = 0; 341 342 (void)acpi_get_gpe_status(NULL, ec->gpe, &gpe_status); 343 return (gpe_status & ACPI_EVENT_FLAG_STATUS_SET) ? true : false; 344 } 345 346 static inline void acpi_ec_enable_gpe(struct acpi_ec *ec, bool open) 347 { 348 if (open) 349 acpi_enable_gpe(NULL, ec->gpe); 350 else { 351 BUG_ON(ec->reference_count < 1); 352 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_ENABLE); 353 } 354 if (acpi_ec_is_gpe_raised(ec)) { 355 /* 356 * On some platforms, EN=1 writes cannot trigger GPE. So 357 * software need to manually trigger a pseudo GPE event on 358 * EN=1 writes. 359 */ 360 ec_dbg_raw("Polling quirk"); 361 advance_transaction(ec); 362 } 363 } 364 365 static inline void acpi_ec_disable_gpe(struct acpi_ec *ec, bool close) 366 { 367 if (close) 368 acpi_disable_gpe(NULL, ec->gpe); 369 else { 370 BUG_ON(ec->reference_count < 1); 371 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_DISABLE); 372 } 373 } 374 375 static inline void acpi_ec_clear_gpe(struct acpi_ec *ec) 376 { 377 /* 378 * GPE STS is a W1C register, which means: 379 * 1. Software can clear it without worrying about clearing other 380 * GPEs' STS bits when the hardware sets them in parallel. 381 * 2. As long as software can ensure only clearing it when it is 382 * set, hardware won't set it in parallel. 383 * So software can clear GPE in any contexts. 384 * Warning: do not move the check into advance_transaction() as the 385 * EC commands will be sent without GPE raised. 386 */ 387 if (!acpi_ec_is_gpe_raised(ec)) 388 return; 389 acpi_clear_gpe(NULL, ec->gpe); 390 } 391 392 /* -------------------------------------------------------------------------- 393 * Transaction Management 394 * -------------------------------------------------------------------------- */ 395 396 static void acpi_ec_submit_request(struct acpi_ec *ec) 397 { 398 ec->reference_count++; 399 if (test_bit(EC_FLAGS_EVENT_HANDLER_INSTALLED, &ec->flags) && 400 ec->gpe >= 0 && ec->reference_count == 1) 401 acpi_ec_enable_gpe(ec, true); 402 } 403 404 static void acpi_ec_complete_request(struct acpi_ec *ec) 405 { 406 bool flushed = false; 407 408 ec->reference_count--; 409 if (test_bit(EC_FLAGS_EVENT_HANDLER_INSTALLED, &ec->flags) && 410 ec->gpe >= 0 && ec->reference_count == 0) 411 acpi_ec_disable_gpe(ec, true); 412 flushed = acpi_ec_flushed(ec); 413 if (flushed) 414 wake_up(&ec->wait); 415 } 416 417 static void acpi_ec_mask_events(struct acpi_ec *ec) 418 { 419 if (!test_bit(EC_FLAGS_EVENTS_MASKED, &ec->flags)) { 420 if (ec->gpe >= 0) 421 acpi_ec_disable_gpe(ec, false); 422 else 423 disable_irq_nosync(ec->irq); 424 425 ec_dbg_drv("Polling enabled"); 426 set_bit(EC_FLAGS_EVENTS_MASKED, &ec->flags); 427 } 428 } 429 430 static void acpi_ec_unmask_events(struct acpi_ec *ec) 431 { 432 if (test_bit(EC_FLAGS_EVENTS_MASKED, &ec->flags)) { 433 clear_bit(EC_FLAGS_EVENTS_MASKED, &ec->flags); 434 if (ec->gpe >= 0) 435 acpi_ec_enable_gpe(ec, false); 436 else 437 enable_irq(ec->irq); 438 439 ec_dbg_drv("Polling disabled"); 440 } 441 } 442 443 /* 444 * acpi_ec_submit_flushable_request() - Increase the reference count unless 445 * the flush operation is not in 446 * progress 447 * @ec: the EC device 448 * 449 * This function must be used before taking a new action that should hold 450 * the reference count. If this function returns false, then the action 451 * must be discarded or it will prevent the flush operation from being 452 * completed. 453 */ 454 static bool acpi_ec_submit_flushable_request(struct acpi_ec *ec) 455 { 456 if (!acpi_ec_started(ec)) 457 return false; 458 acpi_ec_submit_request(ec); 459 return true; 460 } 461 462 static void acpi_ec_submit_query(struct acpi_ec *ec) 463 { 464 acpi_ec_mask_events(ec); 465 if (!acpi_ec_event_enabled(ec)) 466 return; 467 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) { 468 ec_dbg_evt("Command(%s) submitted/blocked", 469 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY)); 470 ec->nr_pending_queries++; 471 queue_work(ec_wq, &ec->work); 472 } 473 } 474 475 static void acpi_ec_complete_query(struct acpi_ec *ec) 476 { 477 if (test_and_clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) 478 ec_dbg_evt("Command(%s) unblocked", 479 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY)); 480 acpi_ec_unmask_events(ec); 481 } 482 483 static inline void __acpi_ec_enable_event(struct acpi_ec *ec) 484 { 485 if (!test_and_set_bit(EC_FLAGS_QUERY_ENABLED, &ec->flags)) 486 ec_log_drv("event unblocked"); 487 /* 488 * Unconditionally invoke this once after enabling the event 489 * handling mechanism to detect the pending events. 490 */ 491 advance_transaction(ec); 492 } 493 494 static inline void __acpi_ec_disable_event(struct acpi_ec *ec) 495 { 496 if (test_and_clear_bit(EC_FLAGS_QUERY_ENABLED, &ec->flags)) 497 ec_log_drv("event blocked"); 498 } 499 500 /* 501 * Process _Q events that might have accumulated in the EC. 502 * Run with locked ec mutex. 503 */ 504 static void acpi_ec_clear(struct acpi_ec *ec) 505 { 506 int i, status; 507 u8 value = 0; 508 509 for (i = 0; i < ACPI_EC_CLEAR_MAX; i++) { 510 status = acpi_ec_query(ec, &value); 511 if (status || !value) 512 break; 513 } 514 if (unlikely(i == ACPI_EC_CLEAR_MAX)) 515 pr_warn("Warning: Maximum of %d stale EC events cleared\n", i); 516 else 517 pr_info("%d stale EC events cleared\n", i); 518 } 519 520 static void acpi_ec_enable_event(struct acpi_ec *ec) 521 { 522 unsigned long flags; 523 524 spin_lock_irqsave(&ec->lock, flags); 525 if (acpi_ec_started(ec)) 526 __acpi_ec_enable_event(ec); 527 spin_unlock_irqrestore(&ec->lock, flags); 528 529 /* Drain additional events if hardware requires that */ 530 if (EC_FLAGS_CLEAR_ON_RESUME) 531 acpi_ec_clear(ec); 532 } 533 534 #ifdef CONFIG_PM_SLEEP 535 static void __acpi_ec_flush_work(void) 536 { 537 drain_workqueue(ec_wq); /* flush ec->work */ 538 flush_workqueue(ec_query_wq); /* flush queries */ 539 } 540 541 static void acpi_ec_disable_event(struct acpi_ec *ec) 542 { 543 unsigned long flags; 544 545 spin_lock_irqsave(&ec->lock, flags); 546 __acpi_ec_disable_event(ec); 547 spin_unlock_irqrestore(&ec->lock, flags); 548 549 /* 550 * When ec_freeze_events is true, we need to flush events in 551 * the proper position before entering the noirq stage. 552 */ 553 __acpi_ec_flush_work(); 554 } 555 556 void acpi_ec_flush_work(void) 557 { 558 /* Without ec_wq there is nothing to flush. */ 559 if (!ec_wq) 560 return; 561 562 __acpi_ec_flush_work(); 563 } 564 #endif /* CONFIG_PM_SLEEP */ 565 566 static bool acpi_ec_guard_event(struct acpi_ec *ec) 567 { 568 bool guarded = true; 569 unsigned long flags; 570 571 spin_lock_irqsave(&ec->lock, flags); 572 /* 573 * If firmware SCI_EVT clearing timing is "event", we actually 574 * don't know when the SCI_EVT will be cleared by firmware after 575 * evaluating _Qxx, so we need to re-check SCI_EVT after waiting an 576 * acceptable period. 577 * 578 * The guarding period begins when EC_FLAGS_QUERY_PENDING is 579 * flagged, which means SCI_EVT check has just been performed. 580 * But if the current transaction is ACPI_EC_COMMAND_QUERY, the 581 * guarding should have already been performed (via 582 * EC_FLAGS_QUERY_GUARDING) and should not be applied so that the 583 * ACPI_EC_COMMAND_QUERY transaction can be transitioned into 584 * ACPI_EC_COMMAND_POLL state immediately. 585 */ 586 if (ec_event_clearing == ACPI_EC_EVT_TIMING_STATUS || 587 ec_event_clearing == ACPI_EC_EVT_TIMING_QUERY || 588 !test_bit(EC_FLAGS_QUERY_PENDING, &ec->flags) || 589 (ec->curr && ec->curr->command == ACPI_EC_COMMAND_QUERY)) 590 guarded = false; 591 spin_unlock_irqrestore(&ec->lock, flags); 592 return guarded; 593 } 594 595 static int ec_transaction_polled(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_POLL)) 602 ret = 1; 603 spin_unlock_irqrestore(&ec->lock, flags); 604 return ret; 605 } 606 607 static int ec_transaction_completed(struct acpi_ec *ec) 608 { 609 unsigned long flags; 610 int ret = 0; 611 612 spin_lock_irqsave(&ec->lock, flags); 613 if (ec->curr && (ec->curr->flags & ACPI_EC_COMMAND_COMPLETE)) 614 ret = 1; 615 spin_unlock_irqrestore(&ec->lock, flags); 616 return ret; 617 } 618 619 static inline void ec_transaction_transition(struct acpi_ec *ec, unsigned long flag) 620 { 621 ec->curr->flags |= flag; 622 if (ec->curr->command == ACPI_EC_COMMAND_QUERY) { 623 if (ec_event_clearing == ACPI_EC_EVT_TIMING_STATUS && 624 flag == ACPI_EC_COMMAND_POLL) 625 acpi_ec_complete_query(ec); 626 if (ec_event_clearing == ACPI_EC_EVT_TIMING_QUERY && 627 flag == ACPI_EC_COMMAND_COMPLETE) 628 acpi_ec_complete_query(ec); 629 if (ec_event_clearing == ACPI_EC_EVT_TIMING_EVENT && 630 flag == ACPI_EC_COMMAND_COMPLETE) 631 set_bit(EC_FLAGS_QUERY_GUARDING, &ec->flags); 632 } 633 } 634 635 static void advance_transaction(struct acpi_ec *ec) 636 { 637 struct transaction *t; 638 u8 status; 639 bool wakeup = false; 640 641 ec_dbg_stm("%s (%d)", in_interrupt() ? "IRQ" : "TASK", 642 smp_processor_id()); 643 /* 644 * By always clearing STS before handling all indications, we can 645 * ensure a hardware STS 0->1 change after this clearing can always 646 * trigger a GPE interrupt. 647 */ 648 if (ec->gpe >= 0) 649 acpi_ec_clear_gpe(ec); 650 651 status = acpi_ec_read_status(ec); 652 t = ec->curr; 653 /* 654 * Another IRQ or a guarded polling mode advancement is detected, 655 * the next QR_EC submission is then allowed. 656 */ 657 if (!t || !(t->flags & ACPI_EC_COMMAND_POLL)) { 658 if (ec_event_clearing == ACPI_EC_EVT_TIMING_EVENT && 659 (!ec->nr_pending_queries || 660 test_bit(EC_FLAGS_QUERY_GUARDING, &ec->flags))) { 661 clear_bit(EC_FLAGS_QUERY_GUARDING, &ec->flags); 662 acpi_ec_complete_query(ec); 663 } 664 } 665 if (!t) 666 goto err; 667 if (t->flags & ACPI_EC_COMMAND_POLL) { 668 if (t->wlen > t->wi) { 669 if ((status & ACPI_EC_FLAG_IBF) == 0) 670 acpi_ec_write_data(ec, t->wdata[t->wi++]); 671 else 672 goto err; 673 } else if (t->rlen > t->ri) { 674 if ((status & ACPI_EC_FLAG_OBF) == 1) { 675 t->rdata[t->ri++] = acpi_ec_read_data(ec); 676 if (t->rlen == t->ri) { 677 ec_transaction_transition(ec, ACPI_EC_COMMAND_COMPLETE); 678 if (t->command == ACPI_EC_COMMAND_QUERY) 679 ec_dbg_evt("Command(%s) completed by hardware", 680 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY)); 681 wakeup = true; 682 } 683 } else 684 goto err; 685 } else if (t->wlen == t->wi && 686 (status & ACPI_EC_FLAG_IBF) == 0) { 687 ec_transaction_transition(ec, ACPI_EC_COMMAND_COMPLETE); 688 wakeup = true; 689 } 690 goto out; 691 } else if (!(status & ACPI_EC_FLAG_IBF)) { 692 acpi_ec_write_cmd(ec, t->command); 693 ec_transaction_transition(ec, ACPI_EC_COMMAND_POLL); 694 goto out; 695 } 696 err: 697 /* 698 * If SCI bit is set, then don't think it's a false IRQ 699 * otherwise will take a not handled IRQ as a false one. 700 */ 701 if (!(status & ACPI_EC_FLAG_SCI)) { 702 if (in_interrupt() && t) { 703 if (t->irq_count < ec_storm_threshold) 704 ++t->irq_count; 705 /* Allow triggering on 0 threshold */ 706 if (t->irq_count == ec_storm_threshold) 707 acpi_ec_mask_events(ec); 708 } 709 } 710 out: 711 if (status & ACPI_EC_FLAG_SCI) 712 acpi_ec_submit_query(ec); 713 if (wakeup && in_interrupt()) 714 wake_up(&ec->wait); 715 } 716 717 static void start_transaction(struct acpi_ec *ec) 718 { 719 ec->curr->irq_count = ec->curr->wi = ec->curr->ri = 0; 720 ec->curr->flags = 0; 721 } 722 723 static int ec_guard(struct acpi_ec *ec) 724 { 725 unsigned long guard = usecs_to_jiffies(ec->polling_guard); 726 unsigned long timeout = ec->timestamp + guard; 727 728 /* Ensure guarding period before polling EC status */ 729 do { 730 if (ec->busy_polling) { 731 /* Perform busy polling */ 732 if (ec_transaction_completed(ec)) 733 return 0; 734 udelay(jiffies_to_usecs(guard)); 735 } else { 736 /* 737 * Perform wait polling 738 * 1. Wait the transaction to be completed by the 739 * GPE handler after the transaction enters 740 * ACPI_EC_COMMAND_POLL state. 741 * 2. A special guarding logic is also required 742 * for event clearing mode "event" before the 743 * transaction enters ACPI_EC_COMMAND_POLL 744 * state. 745 */ 746 if (!ec_transaction_polled(ec) && 747 !acpi_ec_guard_event(ec)) 748 break; 749 if (wait_event_timeout(ec->wait, 750 ec_transaction_completed(ec), 751 guard)) 752 return 0; 753 } 754 } while (time_before(jiffies, timeout)); 755 return -ETIME; 756 } 757 758 static int ec_poll(struct acpi_ec *ec) 759 { 760 unsigned long flags; 761 int repeat = 5; /* number of command restarts */ 762 763 while (repeat--) { 764 unsigned long delay = jiffies + 765 msecs_to_jiffies(ec_delay); 766 do { 767 if (!ec_guard(ec)) 768 return 0; 769 spin_lock_irqsave(&ec->lock, flags); 770 advance_transaction(ec); 771 spin_unlock_irqrestore(&ec->lock, flags); 772 } while (time_before(jiffies, delay)); 773 pr_debug("controller reset, restart transaction\n"); 774 spin_lock_irqsave(&ec->lock, flags); 775 start_transaction(ec); 776 spin_unlock_irqrestore(&ec->lock, flags); 777 } 778 return -ETIME; 779 } 780 781 static int acpi_ec_transaction_unlocked(struct acpi_ec *ec, 782 struct transaction *t) 783 { 784 unsigned long tmp; 785 int ret = 0; 786 787 /* start transaction */ 788 spin_lock_irqsave(&ec->lock, tmp); 789 /* Enable GPE for command processing (IBF=0/OBF=1) */ 790 if (!acpi_ec_submit_flushable_request(ec)) { 791 ret = -EINVAL; 792 goto unlock; 793 } 794 ec_dbg_ref(ec, "Increase command"); 795 /* following two actions should be kept atomic */ 796 ec->curr = t; 797 ec_dbg_req("Command(%s) started", acpi_ec_cmd_string(t->command)); 798 start_transaction(ec); 799 spin_unlock_irqrestore(&ec->lock, tmp); 800 801 ret = ec_poll(ec); 802 803 spin_lock_irqsave(&ec->lock, tmp); 804 if (t->irq_count == ec_storm_threshold) 805 acpi_ec_unmask_events(ec); 806 ec_dbg_req("Command(%s) stopped", acpi_ec_cmd_string(t->command)); 807 ec->curr = NULL; 808 /* Disable GPE for command processing (IBF=0/OBF=1) */ 809 acpi_ec_complete_request(ec); 810 ec_dbg_ref(ec, "Decrease command"); 811 unlock: 812 spin_unlock_irqrestore(&ec->lock, tmp); 813 return ret; 814 } 815 816 static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t) 817 { 818 int status; 819 u32 glk; 820 821 if (!ec || (!t) || (t->wlen && !t->wdata) || (t->rlen && !t->rdata)) 822 return -EINVAL; 823 if (t->rdata) 824 memset(t->rdata, 0, t->rlen); 825 826 mutex_lock(&ec->mutex); 827 if (ec->global_lock) { 828 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk); 829 if (ACPI_FAILURE(status)) { 830 status = -ENODEV; 831 goto unlock; 832 } 833 } 834 835 status = acpi_ec_transaction_unlocked(ec, t); 836 837 if (ec->global_lock) 838 acpi_release_global_lock(glk); 839 unlock: 840 mutex_unlock(&ec->mutex); 841 return status; 842 } 843 844 static int acpi_ec_burst_enable(struct acpi_ec *ec) 845 { 846 u8 d; 847 struct transaction t = {.command = ACPI_EC_BURST_ENABLE, 848 .wdata = NULL, .rdata = &d, 849 .wlen = 0, .rlen = 1}; 850 851 return acpi_ec_transaction(ec, &t); 852 } 853 854 static int acpi_ec_burst_disable(struct acpi_ec *ec) 855 { 856 struct transaction t = {.command = ACPI_EC_BURST_DISABLE, 857 .wdata = NULL, .rdata = NULL, 858 .wlen = 0, .rlen = 0}; 859 860 return (acpi_ec_read_status(ec) & ACPI_EC_FLAG_BURST) ? 861 acpi_ec_transaction(ec, &t) : 0; 862 } 863 864 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 *data) 865 { 866 int result; 867 u8 d; 868 struct transaction t = {.command = ACPI_EC_COMMAND_READ, 869 .wdata = &address, .rdata = &d, 870 .wlen = 1, .rlen = 1}; 871 872 result = acpi_ec_transaction(ec, &t); 873 *data = d; 874 return result; 875 } 876 877 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data) 878 { 879 u8 wdata[2] = { address, data }; 880 struct transaction t = {.command = ACPI_EC_COMMAND_WRITE, 881 .wdata = wdata, .rdata = NULL, 882 .wlen = 2, .rlen = 0}; 883 884 return acpi_ec_transaction(ec, &t); 885 } 886 887 int ec_read(u8 addr, u8 *val) 888 { 889 int err; 890 u8 temp_data; 891 892 if (!first_ec) 893 return -ENODEV; 894 895 err = acpi_ec_read(first_ec, addr, &temp_data); 896 897 if (!err) { 898 *val = temp_data; 899 return 0; 900 } 901 return err; 902 } 903 EXPORT_SYMBOL(ec_read); 904 905 int ec_write(u8 addr, u8 val) 906 { 907 int err; 908 909 if (!first_ec) 910 return -ENODEV; 911 912 err = acpi_ec_write(first_ec, addr, val); 913 914 return err; 915 } 916 EXPORT_SYMBOL(ec_write); 917 918 int ec_transaction(u8 command, 919 const u8 *wdata, unsigned wdata_len, 920 u8 *rdata, unsigned rdata_len) 921 { 922 struct transaction t = {.command = command, 923 .wdata = wdata, .rdata = rdata, 924 .wlen = wdata_len, .rlen = rdata_len}; 925 926 if (!first_ec) 927 return -ENODEV; 928 929 return acpi_ec_transaction(first_ec, &t); 930 } 931 EXPORT_SYMBOL(ec_transaction); 932 933 /* Get the handle to the EC device */ 934 acpi_handle ec_get_handle(void) 935 { 936 if (!first_ec) 937 return NULL; 938 return first_ec->handle; 939 } 940 EXPORT_SYMBOL(ec_get_handle); 941 942 static void acpi_ec_start(struct acpi_ec *ec, bool resuming) 943 { 944 unsigned long flags; 945 946 spin_lock_irqsave(&ec->lock, flags); 947 if (!test_and_set_bit(EC_FLAGS_STARTED, &ec->flags)) { 948 ec_dbg_drv("Starting EC"); 949 /* Enable GPE for event processing (SCI_EVT=1) */ 950 if (!resuming) { 951 acpi_ec_submit_request(ec); 952 ec_dbg_ref(ec, "Increase driver"); 953 } 954 ec_log_drv("EC started"); 955 } 956 spin_unlock_irqrestore(&ec->lock, flags); 957 } 958 959 static bool acpi_ec_stopped(struct acpi_ec *ec) 960 { 961 unsigned long flags; 962 bool flushed; 963 964 spin_lock_irqsave(&ec->lock, flags); 965 flushed = acpi_ec_flushed(ec); 966 spin_unlock_irqrestore(&ec->lock, flags); 967 return flushed; 968 } 969 970 static void acpi_ec_stop(struct acpi_ec *ec, bool suspending) 971 { 972 unsigned long flags; 973 974 spin_lock_irqsave(&ec->lock, flags); 975 if (acpi_ec_started(ec)) { 976 ec_dbg_drv("Stopping EC"); 977 set_bit(EC_FLAGS_STOPPED, &ec->flags); 978 spin_unlock_irqrestore(&ec->lock, flags); 979 wait_event(ec->wait, acpi_ec_stopped(ec)); 980 spin_lock_irqsave(&ec->lock, flags); 981 /* Disable GPE for event processing (SCI_EVT=1) */ 982 if (!suspending) { 983 acpi_ec_complete_request(ec); 984 ec_dbg_ref(ec, "Decrease driver"); 985 } else if (!ec_freeze_events) 986 __acpi_ec_disable_event(ec); 987 clear_bit(EC_FLAGS_STARTED, &ec->flags); 988 clear_bit(EC_FLAGS_STOPPED, &ec->flags); 989 ec_log_drv("EC stopped"); 990 } 991 spin_unlock_irqrestore(&ec->lock, flags); 992 } 993 994 static void acpi_ec_enter_noirq(struct acpi_ec *ec) 995 { 996 unsigned long flags; 997 998 spin_lock_irqsave(&ec->lock, flags); 999 ec->busy_polling = true; 1000 ec->polling_guard = 0; 1001 ec_log_drv("interrupt blocked"); 1002 spin_unlock_irqrestore(&ec->lock, flags); 1003 } 1004 1005 static void acpi_ec_leave_noirq(struct acpi_ec *ec) 1006 { 1007 unsigned long flags; 1008 1009 spin_lock_irqsave(&ec->lock, flags); 1010 ec->busy_polling = ec_busy_polling; 1011 ec->polling_guard = ec_polling_guard; 1012 ec_log_drv("interrupt unblocked"); 1013 spin_unlock_irqrestore(&ec->lock, flags); 1014 } 1015 1016 void acpi_ec_block_transactions(void) 1017 { 1018 struct acpi_ec *ec = first_ec; 1019 1020 if (!ec) 1021 return; 1022 1023 mutex_lock(&ec->mutex); 1024 /* Prevent transactions from being carried out */ 1025 acpi_ec_stop(ec, true); 1026 mutex_unlock(&ec->mutex); 1027 } 1028 1029 void acpi_ec_unblock_transactions(void) 1030 { 1031 /* 1032 * Allow transactions to happen again (this function is called from 1033 * atomic context during wakeup, so we don't need to acquire the mutex). 1034 */ 1035 if (first_ec) 1036 acpi_ec_start(first_ec, true); 1037 } 1038 1039 /* -------------------------------------------------------------------------- 1040 Event Management 1041 -------------------------------------------------------------------------- */ 1042 static struct acpi_ec_query_handler * 1043 acpi_ec_get_query_handler_by_value(struct acpi_ec *ec, u8 value) 1044 { 1045 struct acpi_ec_query_handler *handler; 1046 1047 mutex_lock(&ec->mutex); 1048 list_for_each_entry(handler, &ec->list, node) { 1049 if (value == handler->query_bit) { 1050 kref_get(&handler->kref); 1051 mutex_unlock(&ec->mutex); 1052 return handler; 1053 } 1054 } 1055 mutex_unlock(&ec->mutex); 1056 return NULL; 1057 } 1058 1059 static void acpi_ec_query_handler_release(struct kref *kref) 1060 { 1061 struct acpi_ec_query_handler *handler = 1062 container_of(kref, struct acpi_ec_query_handler, kref); 1063 1064 kfree(handler); 1065 } 1066 1067 static void acpi_ec_put_query_handler(struct acpi_ec_query_handler *handler) 1068 { 1069 kref_put(&handler->kref, acpi_ec_query_handler_release); 1070 } 1071 1072 int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit, 1073 acpi_handle handle, acpi_ec_query_func func, 1074 void *data) 1075 { 1076 struct acpi_ec_query_handler *handler = 1077 kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL); 1078 1079 if (!handler) 1080 return -ENOMEM; 1081 1082 handler->query_bit = query_bit; 1083 handler->handle = handle; 1084 handler->func = func; 1085 handler->data = data; 1086 mutex_lock(&ec->mutex); 1087 kref_init(&handler->kref); 1088 list_add(&handler->node, &ec->list); 1089 mutex_unlock(&ec->mutex); 1090 return 0; 1091 } 1092 EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler); 1093 1094 static void acpi_ec_remove_query_handlers(struct acpi_ec *ec, 1095 bool remove_all, u8 query_bit) 1096 { 1097 struct acpi_ec_query_handler *handler, *tmp; 1098 LIST_HEAD(free_list); 1099 1100 mutex_lock(&ec->mutex); 1101 list_for_each_entry_safe(handler, tmp, &ec->list, node) { 1102 if (remove_all || query_bit == handler->query_bit) { 1103 list_del_init(&handler->node); 1104 list_add(&handler->node, &free_list); 1105 } 1106 } 1107 mutex_unlock(&ec->mutex); 1108 list_for_each_entry_safe(handler, tmp, &free_list, node) 1109 acpi_ec_put_query_handler(handler); 1110 } 1111 1112 void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit) 1113 { 1114 acpi_ec_remove_query_handlers(ec, false, query_bit); 1115 } 1116 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler); 1117 1118 static struct acpi_ec_query *acpi_ec_create_query(u8 *pval) 1119 { 1120 struct acpi_ec_query *q; 1121 struct transaction *t; 1122 1123 q = kzalloc(sizeof (struct acpi_ec_query), GFP_KERNEL); 1124 if (!q) 1125 return NULL; 1126 INIT_WORK(&q->work, acpi_ec_event_processor); 1127 t = &q->transaction; 1128 t->command = ACPI_EC_COMMAND_QUERY; 1129 t->rdata = pval; 1130 t->rlen = 1; 1131 return q; 1132 } 1133 1134 static void acpi_ec_delete_query(struct acpi_ec_query *q) 1135 { 1136 if (q) { 1137 if (q->handler) 1138 acpi_ec_put_query_handler(q->handler); 1139 kfree(q); 1140 } 1141 } 1142 1143 static void acpi_ec_event_processor(struct work_struct *work) 1144 { 1145 struct acpi_ec_query *q = container_of(work, struct acpi_ec_query, work); 1146 struct acpi_ec_query_handler *handler = q->handler; 1147 1148 ec_dbg_evt("Query(0x%02x) started", handler->query_bit); 1149 if (handler->func) 1150 handler->func(handler->data); 1151 else if (handler->handle) 1152 acpi_evaluate_object(handler->handle, NULL, NULL, NULL); 1153 ec_dbg_evt("Query(0x%02x) stopped", handler->query_bit); 1154 acpi_ec_delete_query(q); 1155 } 1156 1157 static int acpi_ec_query(struct acpi_ec *ec, u8 *data) 1158 { 1159 u8 value = 0; 1160 int result; 1161 struct acpi_ec_query *q; 1162 1163 q = acpi_ec_create_query(&value); 1164 if (!q) 1165 return -ENOMEM; 1166 1167 /* 1168 * Query the EC to find out which _Qxx method we need to evaluate. 1169 * Note that successful completion of the query causes the ACPI_EC_SCI 1170 * bit to be cleared (and thus clearing the interrupt source). 1171 */ 1172 result = acpi_ec_transaction(ec, &q->transaction); 1173 if (!value) 1174 result = -ENODATA; 1175 if (result) 1176 goto err_exit; 1177 1178 q->handler = acpi_ec_get_query_handler_by_value(ec, value); 1179 if (!q->handler) { 1180 result = -ENODATA; 1181 goto err_exit; 1182 } 1183 1184 /* 1185 * It is reported that _Qxx are evaluated in a parallel way on 1186 * Windows: 1187 * https://bugzilla.kernel.org/show_bug.cgi?id=94411 1188 * 1189 * Put this log entry before schedule_work() in order to make 1190 * it appearing before any other log entries occurred during the 1191 * work queue execution. 1192 */ 1193 ec_dbg_evt("Query(0x%02x) scheduled", value); 1194 if (!queue_work(ec_query_wq, &q->work)) { 1195 ec_dbg_evt("Query(0x%02x) overlapped", value); 1196 result = -EBUSY; 1197 } 1198 1199 err_exit: 1200 if (result) 1201 acpi_ec_delete_query(q); 1202 if (data) 1203 *data = value; 1204 return result; 1205 } 1206 1207 static void acpi_ec_check_event(struct acpi_ec *ec) 1208 { 1209 unsigned long flags; 1210 1211 if (ec_event_clearing == ACPI_EC_EVT_TIMING_EVENT) { 1212 if (ec_guard(ec)) { 1213 spin_lock_irqsave(&ec->lock, flags); 1214 /* 1215 * Take care of the SCI_EVT unless no one else is 1216 * taking care of it. 1217 */ 1218 if (!ec->curr) 1219 advance_transaction(ec); 1220 spin_unlock_irqrestore(&ec->lock, flags); 1221 } 1222 } 1223 } 1224 1225 static void acpi_ec_event_handler(struct work_struct *work) 1226 { 1227 unsigned long flags; 1228 struct acpi_ec *ec = container_of(work, struct acpi_ec, work); 1229 1230 ec_dbg_evt("Event started"); 1231 1232 spin_lock_irqsave(&ec->lock, flags); 1233 while (ec->nr_pending_queries) { 1234 spin_unlock_irqrestore(&ec->lock, flags); 1235 (void)acpi_ec_query(ec, NULL); 1236 spin_lock_irqsave(&ec->lock, flags); 1237 ec->nr_pending_queries--; 1238 /* 1239 * Before exit, make sure that this work item can be 1240 * scheduled again. There might be QR_EC failures, leaving 1241 * EC_FLAGS_QUERY_PENDING uncleared and preventing this work 1242 * item from being scheduled again. 1243 */ 1244 if (!ec->nr_pending_queries) { 1245 if (ec_event_clearing == ACPI_EC_EVT_TIMING_STATUS || 1246 ec_event_clearing == ACPI_EC_EVT_TIMING_QUERY) 1247 acpi_ec_complete_query(ec); 1248 } 1249 } 1250 spin_unlock_irqrestore(&ec->lock, flags); 1251 1252 ec_dbg_evt("Event stopped"); 1253 1254 acpi_ec_check_event(ec); 1255 } 1256 1257 static void acpi_ec_handle_interrupt(struct acpi_ec *ec) 1258 { 1259 unsigned long flags; 1260 1261 spin_lock_irqsave(&ec->lock, flags); 1262 advance_transaction(ec); 1263 spin_unlock_irqrestore(&ec->lock, flags); 1264 } 1265 1266 static u32 acpi_ec_gpe_handler(acpi_handle gpe_device, 1267 u32 gpe_number, void *data) 1268 { 1269 acpi_ec_handle_interrupt(data); 1270 return ACPI_INTERRUPT_HANDLED; 1271 } 1272 1273 static irqreturn_t acpi_ec_irq_handler(int irq, void *data) 1274 { 1275 acpi_ec_handle_interrupt(data); 1276 return IRQ_HANDLED; 1277 } 1278 1279 /* -------------------------------------------------------------------------- 1280 * Address Space Management 1281 * -------------------------------------------------------------------------- */ 1282 1283 static acpi_status 1284 acpi_ec_space_handler(u32 function, acpi_physical_address address, 1285 u32 bits, u64 *value64, 1286 void *handler_context, void *region_context) 1287 { 1288 struct acpi_ec *ec = handler_context; 1289 int result = 0, i, bytes = bits / 8; 1290 u8 *value = (u8 *)value64; 1291 1292 if ((address > 0xFF) || !value || !handler_context) 1293 return AE_BAD_PARAMETER; 1294 1295 if (function != ACPI_READ && function != ACPI_WRITE) 1296 return AE_BAD_PARAMETER; 1297 1298 if (ec->busy_polling || bits > 8) 1299 acpi_ec_burst_enable(ec); 1300 1301 for (i = 0; i < bytes; ++i, ++address, ++value) 1302 result = (function == ACPI_READ) ? 1303 acpi_ec_read(ec, address, value) : 1304 acpi_ec_write(ec, address, *value); 1305 1306 if (ec->busy_polling || bits > 8) 1307 acpi_ec_burst_disable(ec); 1308 1309 switch (result) { 1310 case -EINVAL: 1311 return AE_BAD_PARAMETER; 1312 case -ENODEV: 1313 return AE_NOT_FOUND; 1314 case -ETIME: 1315 return AE_TIME; 1316 default: 1317 return AE_OK; 1318 } 1319 } 1320 1321 /* -------------------------------------------------------------------------- 1322 * Driver Interface 1323 * -------------------------------------------------------------------------- */ 1324 1325 static acpi_status 1326 ec_parse_io_ports(struct acpi_resource *resource, void *context); 1327 1328 static void acpi_ec_free(struct acpi_ec *ec) 1329 { 1330 if (first_ec == ec) 1331 first_ec = NULL; 1332 if (boot_ec == ec) 1333 boot_ec = NULL; 1334 kfree(ec); 1335 } 1336 1337 static struct acpi_ec *acpi_ec_alloc(void) 1338 { 1339 struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL); 1340 1341 if (!ec) 1342 return NULL; 1343 mutex_init(&ec->mutex); 1344 init_waitqueue_head(&ec->wait); 1345 INIT_LIST_HEAD(&ec->list); 1346 spin_lock_init(&ec->lock); 1347 INIT_WORK(&ec->work, acpi_ec_event_handler); 1348 ec->timestamp = jiffies; 1349 ec->busy_polling = true; 1350 ec->polling_guard = 0; 1351 ec->gpe = -1; 1352 ec->irq = -1; 1353 return ec; 1354 } 1355 1356 static acpi_status 1357 acpi_ec_register_query_methods(acpi_handle handle, u32 level, 1358 void *context, void **return_value) 1359 { 1360 char node_name[5]; 1361 struct acpi_buffer buffer = { sizeof(node_name), node_name }; 1362 struct acpi_ec *ec = context; 1363 int value = 0; 1364 acpi_status status; 1365 1366 status = acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer); 1367 1368 if (ACPI_SUCCESS(status) && sscanf(node_name, "_Q%x", &value) == 1) 1369 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL); 1370 return AE_OK; 1371 } 1372 1373 static acpi_status 1374 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval) 1375 { 1376 acpi_status status; 1377 unsigned long long tmp = 0; 1378 struct acpi_ec *ec = context; 1379 1380 /* clear addr values, ec_parse_io_ports depend on it */ 1381 ec->command_addr = ec->data_addr = 0; 1382 1383 status = acpi_walk_resources(handle, METHOD_NAME__CRS, 1384 ec_parse_io_ports, ec); 1385 if (ACPI_FAILURE(status)) 1386 return status; 1387 if (ec->data_addr == 0 || ec->command_addr == 0) 1388 return AE_OK; 1389 1390 if (boot_ec && boot_ec_is_ecdt && EC_FLAGS_IGNORE_DSDT_GPE) { 1391 /* 1392 * Always inherit the GPE number setting from the ECDT 1393 * EC. 1394 */ 1395 ec->gpe = boot_ec->gpe; 1396 } else { 1397 /* Get GPE bit assignment (EC events). */ 1398 /* TODO: Add support for _GPE returning a package */ 1399 status = acpi_evaluate_integer(handle, "_GPE", NULL, &tmp); 1400 if (ACPI_SUCCESS(status)) 1401 ec->gpe = tmp; 1402 1403 /* 1404 * Errors are non-fatal, allowing for ACPI Reduced Hardware 1405 * platforms which use GpioInt instead of GPE. 1406 */ 1407 } 1408 /* Use the global lock for all EC transactions? */ 1409 tmp = 0; 1410 acpi_evaluate_integer(handle, "_GLK", NULL, &tmp); 1411 ec->global_lock = tmp; 1412 ec->handle = handle; 1413 return AE_CTRL_TERMINATE; 1414 } 1415 1416 static bool install_gpe_event_handler(struct acpi_ec *ec) 1417 { 1418 acpi_status status; 1419 1420 status = acpi_install_gpe_raw_handler(NULL, ec->gpe, 1421 ACPI_GPE_EDGE_TRIGGERED, 1422 &acpi_ec_gpe_handler, ec); 1423 if (ACPI_FAILURE(status)) 1424 return false; 1425 1426 if (test_bit(EC_FLAGS_STARTED, &ec->flags) && ec->reference_count >= 1) 1427 acpi_ec_enable_gpe(ec, true); 1428 1429 return true; 1430 } 1431 1432 static bool install_gpio_irq_event_handler(struct acpi_ec *ec) 1433 { 1434 return request_irq(ec->irq, acpi_ec_irq_handler, IRQF_SHARED, 1435 "ACPI EC", ec) >= 0; 1436 } 1437 1438 /** 1439 * ec_install_handlers - Install service callbacks and register query methods. 1440 * @ec: Target EC. 1441 * @device: ACPI device object corresponding to @ec. 1442 * 1443 * Install a handler for the EC address space type unless it has been installed 1444 * already. If @device is not NULL, also look for EC query methods in the 1445 * namespace and register them, and install an event (either GPE or GPIO IRQ) 1446 * handler for the EC, if possible. 1447 * 1448 * Return: 1449 * -ENODEV if the address space handler cannot be installed, which means 1450 * "unable to handle transactions", 1451 * -EPROBE_DEFER if GPIO IRQ acquisition needs to be deferred, 1452 * or 0 (success) otherwise. 1453 */ 1454 static int ec_install_handlers(struct acpi_ec *ec, struct acpi_device *device) 1455 { 1456 acpi_status status; 1457 1458 acpi_ec_start(ec, false); 1459 1460 if (!test_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags)) { 1461 acpi_ec_enter_noirq(ec); 1462 status = acpi_install_address_space_handler(ec->handle, 1463 ACPI_ADR_SPACE_EC, 1464 &acpi_ec_space_handler, 1465 NULL, ec); 1466 if (ACPI_FAILURE(status)) { 1467 acpi_ec_stop(ec, false); 1468 return -ENODEV; 1469 } 1470 set_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags); 1471 } 1472 1473 if (!device) 1474 return 0; 1475 1476 if (ec->gpe < 0) { 1477 /* ACPI reduced hardware platforms use a GpioInt from _CRS. */ 1478 int irq = acpi_dev_gpio_irq_get(device, 0); 1479 /* 1480 * Bail out right away for deferred probing or complete the 1481 * initialization regardless of any other errors. 1482 */ 1483 if (irq == -EPROBE_DEFER) 1484 return -EPROBE_DEFER; 1485 else if (irq >= 0) 1486 ec->irq = irq; 1487 } 1488 1489 if (!test_bit(EC_FLAGS_QUERY_METHODS_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_QUERY_METHODS_INSTALLED, &ec->flags); 1495 } 1496 if (!test_bit(EC_FLAGS_EVENT_HANDLER_INSTALLED, &ec->flags)) { 1497 bool ready = false; 1498 1499 if (ec->gpe >= 0) 1500 ready = install_gpe_event_handler(ec); 1501 else if (ec->irq >= 0) 1502 ready = install_gpio_irq_event_handler(ec); 1503 1504 if (ready) { 1505 set_bit(EC_FLAGS_EVENT_HANDLER_INSTALLED, &ec->flags); 1506 acpi_ec_leave_noirq(ec); 1507 } 1508 /* 1509 * Failures to install an event handler are not fatal, because 1510 * the EC can be polled for events. 1511 */ 1512 } 1513 /* EC is fully operational, allow queries */ 1514 acpi_ec_enable_event(ec); 1515 1516 return 0; 1517 } 1518 1519 static void ec_remove_handlers(struct acpi_ec *ec) 1520 { 1521 if (test_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags)) { 1522 if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle, 1523 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler))) 1524 pr_err("failed to remove space handler\n"); 1525 clear_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags); 1526 } 1527 1528 /* 1529 * Stops handling the EC transactions after removing the operation 1530 * region handler. This is required because _REG(DISCONNECT) 1531 * invoked during the removal can result in new EC transactions. 1532 * 1533 * Flushes the EC requests and thus disables the GPE before 1534 * removing the GPE handler. This is required by the current ACPICA 1535 * GPE core. ACPICA GPE core will automatically disable a GPE when 1536 * it is indicated but there is no way to handle it. So the drivers 1537 * must disable the GPEs prior to removing the GPE handlers. 1538 */ 1539 acpi_ec_stop(ec, false); 1540 1541 if (test_bit(EC_FLAGS_EVENT_HANDLER_INSTALLED, &ec->flags)) { 1542 if (ec->gpe >= 0 && 1543 ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe, 1544 &acpi_ec_gpe_handler))) 1545 pr_err("failed to remove gpe handler\n"); 1546 1547 if (ec->irq >= 0) 1548 free_irq(ec->irq, ec); 1549 1550 clear_bit(EC_FLAGS_EVENT_HANDLER_INSTALLED, &ec->flags); 1551 } 1552 if (test_bit(EC_FLAGS_QUERY_METHODS_INSTALLED, &ec->flags)) { 1553 acpi_ec_remove_query_handlers(ec, true, 0); 1554 clear_bit(EC_FLAGS_QUERY_METHODS_INSTALLED, &ec->flags); 1555 } 1556 } 1557 1558 static int acpi_ec_setup(struct acpi_ec *ec, struct acpi_device *device) 1559 { 1560 int ret; 1561 1562 ret = ec_install_handlers(ec, device); 1563 if (ret) 1564 return ret; 1565 1566 /* First EC capable of handling transactions */ 1567 if (!first_ec) 1568 first_ec = ec; 1569 1570 pr_info("EC_CMD/EC_SC=0x%lx, EC_DATA=0x%lx\n", ec->command_addr, 1571 ec->data_addr); 1572 1573 if (test_bit(EC_FLAGS_EVENT_HANDLER_INSTALLED, &ec->flags)) { 1574 if (ec->gpe >= 0) 1575 pr_info("GPE=0x%x\n", ec->gpe); 1576 else 1577 pr_info("IRQ=%d\n", ec->irq); 1578 } 1579 1580 return ret; 1581 } 1582 1583 static int acpi_ec_add(struct acpi_device *device) 1584 { 1585 struct acpi_ec *ec; 1586 int ret; 1587 1588 strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME); 1589 strcpy(acpi_device_class(device), ACPI_EC_CLASS); 1590 1591 if (boot_ec && (boot_ec->handle == device->handle || 1592 !strcmp(acpi_device_hid(device), ACPI_ECDT_HID))) { 1593 /* Fast path: this device corresponds to the boot EC. */ 1594 ec = boot_ec; 1595 } else { 1596 acpi_status status; 1597 1598 ec = acpi_ec_alloc(); 1599 if (!ec) 1600 return -ENOMEM; 1601 1602 status = ec_parse_device(device->handle, 0, ec, NULL); 1603 if (status != AE_CTRL_TERMINATE) { 1604 ret = -EINVAL; 1605 goto err; 1606 } 1607 1608 if (boot_ec && ec->command_addr == boot_ec->command_addr && 1609 ec->data_addr == boot_ec->data_addr) { 1610 /* 1611 * Trust PNP0C09 namespace location rather than 1612 * ECDT ID. But trust ECDT GPE rather than _GPE 1613 * because of ASUS quirks, so do not change 1614 * boot_ec->gpe to ec->gpe. 1615 */ 1616 boot_ec->handle = ec->handle; 1617 acpi_handle_debug(ec->handle, "duplicated.\n"); 1618 acpi_ec_free(ec); 1619 ec = boot_ec; 1620 } 1621 } 1622 1623 ret = acpi_ec_setup(ec, device); 1624 if (ret) 1625 goto err; 1626 1627 if (ec == boot_ec) 1628 acpi_handle_info(boot_ec->handle, 1629 "Boot %s EC initialization complete\n", 1630 boot_ec_is_ecdt ? "ECDT" : "DSDT"); 1631 1632 acpi_handle_info(ec->handle, 1633 "EC: Used to handle transactions and events\n"); 1634 1635 device->driver_data = ec; 1636 1637 ret = !!request_region(ec->data_addr, 1, "EC data"); 1638 WARN(!ret, "Could not request EC data io port 0x%lx", ec->data_addr); 1639 ret = !!request_region(ec->command_addr, 1, "EC cmd"); 1640 WARN(!ret, "Could not request EC cmd io port 0x%lx", ec->command_addr); 1641 1642 /* Reprobe devices depending on the EC */ 1643 acpi_walk_dep_device_list(ec->handle); 1644 1645 acpi_handle_debug(ec->handle, "enumerated.\n"); 1646 return 0; 1647 1648 err: 1649 if (ec != boot_ec) 1650 acpi_ec_free(ec); 1651 1652 return ret; 1653 } 1654 1655 static int acpi_ec_remove(struct acpi_device *device) 1656 { 1657 struct acpi_ec *ec; 1658 1659 if (!device) 1660 return -EINVAL; 1661 1662 ec = acpi_driver_data(device); 1663 release_region(ec->data_addr, 1); 1664 release_region(ec->command_addr, 1); 1665 device->driver_data = NULL; 1666 if (ec != boot_ec) { 1667 ec_remove_handlers(ec); 1668 acpi_ec_free(ec); 1669 } 1670 return 0; 1671 } 1672 1673 static acpi_status 1674 ec_parse_io_ports(struct acpi_resource *resource, void *context) 1675 { 1676 struct acpi_ec *ec = context; 1677 1678 if (resource->type != ACPI_RESOURCE_TYPE_IO) 1679 return AE_OK; 1680 1681 /* 1682 * The first address region returned is the data port, and 1683 * the second address region returned is the status/command 1684 * port. 1685 */ 1686 if (ec->data_addr == 0) 1687 ec->data_addr = resource->data.io.minimum; 1688 else if (ec->command_addr == 0) 1689 ec->command_addr = resource->data.io.minimum; 1690 else 1691 return AE_CTRL_TERMINATE; 1692 1693 return AE_OK; 1694 } 1695 1696 static const struct acpi_device_id ec_device_ids[] = { 1697 {"PNP0C09", 0}, 1698 {ACPI_ECDT_HID, 0}, 1699 {"", 0}, 1700 }; 1701 1702 /* 1703 * This function is not Windows-compatible as Windows never enumerates the 1704 * namespace EC before the main ACPI device enumeration process. It is 1705 * retained for historical reason and will be deprecated in the future. 1706 */ 1707 void __init acpi_ec_dsdt_probe(void) 1708 { 1709 struct acpi_ec *ec; 1710 acpi_status status; 1711 int ret; 1712 1713 /* 1714 * If a platform has ECDT, there is no need to proceed as the 1715 * following probe is not a part of the ACPI device enumeration, 1716 * executing _STA is not safe, and thus this probe may risk of 1717 * picking up an invalid EC device. 1718 */ 1719 if (boot_ec) 1720 return; 1721 1722 ec = acpi_ec_alloc(); 1723 if (!ec) 1724 return; 1725 1726 /* 1727 * At this point, the namespace is initialized, so start to find 1728 * the namespace objects. 1729 */ 1730 status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device, ec, NULL); 1731 if (ACPI_FAILURE(status) || !ec->handle) { 1732 acpi_ec_free(ec); 1733 return; 1734 } 1735 1736 /* 1737 * When the DSDT EC is available, always re-configure boot EC to 1738 * have _REG evaluated. _REG can only be evaluated after the 1739 * namespace initialization. 1740 * At this point, the GPE is not fully initialized, so do not to 1741 * handle the events. 1742 */ 1743 ret = acpi_ec_setup(ec, NULL); 1744 if (ret) { 1745 acpi_ec_free(ec); 1746 return; 1747 } 1748 1749 boot_ec = ec; 1750 1751 acpi_handle_info(ec->handle, 1752 "Boot DSDT EC used to handle transactions\n"); 1753 } 1754 1755 /* 1756 * acpi_ec_ecdt_start - Finalize the boot ECDT EC initialization. 1757 * 1758 * First, look for an ACPI handle for the boot ECDT EC if acpi_ec_add() has not 1759 * found a matching object in the namespace. 1760 * 1761 * Next, in case the DSDT EC is not functioning, it is still necessary to 1762 * provide a functional ECDT EC to handle events, so add an extra device object 1763 * to represent it (see https://bugzilla.kernel.org/show_bug.cgi?id=115021). 1764 * 1765 * This is useful on platforms with valid ECDT and invalid DSDT EC settings, 1766 * like ASUS X550ZE (see https://bugzilla.kernel.org/show_bug.cgi?id=196847). 1767 */ 1768 static void __init acpi_ec_ecdt_start(void) 1769 { 1770 struct acpi_table_ecdt *ecdt_ptr; 1771 acpi_handle handle; 1772 acpi_status status; 1773 1774 /* Bail out if a matching EC has been found in the namespace. */ 1775 if (!boot_ec || boot_ec->handle != ACPI_ROOT_OBJECT) 1776 return; 1777 1778 /* Look up the object pointed to from the ECDT in the namespace. */ 1779 status = acpi_get_table(ACPI_SIG_ECDT, 1, 1780 (struct acpi_table_header **)&ecdt_ptr); 1781 if (ACPI_FAILURE(status)) 1782 return; 1783 1784 status = acpi_get_handle(NULL, ecdt_ptr->id, &handle); 1785 if (ACPI_SUCCESS(status)) { 1786 boot_ec->handle = handle; 1787 1788 /* Add a special ACPI device object to represent the boot EC. */ 1789 acpi_bus_register_early_device(ACPI_BUS_TYPE_ECDT_EC); 1790 } 1791 1792 acpi_put_table((struct acpi_table_header *)ecdt_ptr); 1793 } 1794 1795 /* 1796 * On some hardware it is necessary to clear events accumulated by the EC during 1797 * sleep. These ECs stop reporting GPEs until they are manually polled, if too 1798 * many events are accumulated. (e.g. Samsung Series 5/9 notebooks) 1799 * 1800 * https://bugzilla.kernel.org/show_bug.cgi?id=44161 1801 * 1802 * Ideally, the EC should also be instructed NOT to accumulate events during 1803 * sleep (which Windows seems to do somehow), but the interface to control this 1804 * behaviour is not known at this time. 1805 * 1806 * Models known to be affected are Samsung 530Uxx/535Uxx/540Uxx/550Pxx/900Xxx, 1807 * however it is very likely that other Samsung models are affected. 1808 * 1809 * On systems which don't accumulate _Q events during sleep, this extra check 1810 * should be harmless. 1811 */ 1812 static int ec_clear_on_resume(const struct dmi_system_id *id) 1813 { 1814 pr_debug("Detected system needing EC poll on resume.\n"); 1815 EC_FLAGS_CLEAR_ON_RESUME = 1; 1816 ec_event_clearing = ACPI_EC_EVT_TIMING_STATUS; 1817 return 0; 1818 } 1819 1820 /* 1821 * Some ECDTs contain wrong register addresses. 1822 * MSI MS-171F 1823 * https://bugzilla.kernel.org/show_bug.cgi?id=12461 1824 */ 1825 static int ec_correct_ecdt(const struct dmi_system_id *id) 1826 { 1827 pr_debug("Detected system needing ECDT address correction.\n"); 1828 EC_FLAGS_CORRECT_ECDT = 1; 1829 return 0; 1830 } 1831 1832 /* 1833 * Some DSDTs contain wrong GPE setting. 1834 * Asus FX502VD/VE, GL702VMK, X550VXK, X580VD 1835 * https://bugzilla.kernel.org/show_bug.cgi?id=195651 1836 */ 1837 static int ec_honor_ecdt_gpe(const struct dmi_system_id *id) 1838 { 1839 pr_debug("Detected system needing ignore DSDT GPE setting.\n"); 1840 EC_FLAGS_IGNORE_DSDT_GPE = 1; 1841 return 0; 1842 } 1843 1844 static const struct dmi_system_id ec_dmi_table[] __initconst = { 1845 { 1846 ec_correct_ecdt, "MSI MS-171F", { 1847 DMI_MATCH(DMI_SYS_VENDOR, "Micro-Star"), 1848 DMI_MATCH(DMI_PRODUCT_NAME, "MS-171F"),}, NULL}, 1849 { 1850 ec_honor_ecdt_gpe, "ASUS FX502VD", { 1851 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."), 1852 DMI_MATCH(DMI_PRODUCT_NAME, "FX502VD"),}, NULL}, 1853 { 1854 ec_honor_ecdt_gpe, "ASUS FX502VE", { 1855 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."), 1856 DMI_MATCH(DMI_PRODUCT_NAME, "FX502VE"),}, NULL}, 1857 { 1858 ec_honor_ecdt_gpe, "ASUS GL702VMK", { 1859 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."), 1860 DMI_MATCH(DMI_PRODUCT_NAME, "GL702VMK"),}, NULL}, 1861 { 1862 ec_honor_ecdt_gpe, "ASUS X550VXK", { 1863 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."), 1864 DMI_MATCH(DMI_PRODUCT_NAME, "X550VXK"),}, NULL}, 1865 { 1866 ec_honor_ecdt_gpe, "ASUS X580VD", { 1867 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."), 1868 DMI_MATCH(DMI_PRODUCT_NAME, "X580VD"),}, NULL}, 1869 { 1870 ec_clear_on_resume, "Samsung hardware", { 1871 DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD.")}, NULL}, 1872 {}, 1873 }; 1874 1875 void __init acpi_ec_ecdt_probe(void) 1876 { 1877 struct acpi_table_ecdt *ecdt_ptr; 1878 struct acpi_ec *ec; 1879 acpi_status status; 1880 int ret; 1881 1882 /* Generate a boot ec context. */ 1883 dmi_check_system(ec_dmi_table); 1884 status = acpi_get_table(ACPI_SIG_ECDT, 1, 1885 (struct acpi_table_header **)&ecdt_ptr); 1886 if (ACPI_FAILURE(status)) 1887 return; 1888 1889 if (!ecdt_ptr->control.address || !ecdt_ptr->data.address) { 1890 /* 1891 * Asus X50GL: 1892 * https://bugzilla.kernel.org/show_bug.cgi?id=11880 1893 */ 1894 goto out; 1895 } 1896 1897 ec = acpi_ec_alloc(); 1898 if (!ec) 1899 goto out; 1900 1901 if (EC_FLAGS_CORRECT_ECDT) { 1902 ec->command_addr = ecdt_ptr->data.address; 1903 ec->data_addr = ecdt_ptr->control.address; 1904 } else { 1905 ec->command_addr = ecdt_ptr->control.address; 1906 ec->data_addr = ecdt_ptr->data.address; 1907 } 1908 1909 /* 1910 * Ignore the GPE value on Reduced Hardware platforms. 1911 * Some products have this set to an erroneous value. 1912 */ 1913 if (!acpi_gbl_reduced_hardware) 1914 ec->gpe = ecdt_ptr->gpe; 1915 1916 ec->handle = ACPI_ROOT_OBJECT; 1917 1918 /* 1919 * At this point, the namespace is not initialized, so do not find 1920 * the namespace objects, or handle the events. 1921 */ 1922 ret = acpi_ec_setup(ec, NULL); 1923 if (ret) { 1924 acpi_ec_free(ec); 1925 goto out; 1926 } 1927 1928 boot_ec = ec; 1929 boot_ec_is_ecdt = true; 1930 1931 pr_info("Boot ECDT EC used to handle transactions\n"); 1932 1933 out: 1934 acpi_put_table((struct acpi_table_header *)ecdt_ptr); 1935 } 1936 1937 #ifdef CONFIG_PM_SLEEP 1938 static int acpi_ec_suspend(struct device *dev) 1939 { 1940 struct acpi_ec *ec = 1941 acpi_driver_data(to_acpi_device(dev)); 1942 1943 if (!pm_suspend_no_platform() && ec_freeze_events) 1944 acpi_ec_disable_event(ec); 1945 return 0; 1946 } 1947 1948 static int acpi_ec_suspend_noirq(struct device *dev) 1949 { 1950 struct acpi_ec *ec = acpi_driver_data(to_acpi_device(dev)); 1951 1952 /* 1953 * The SCI handler doesn't run at this point, so the GPE can be 1954 * masked at the low level without side effects. 1955 */ 1956 if (ec_no_wakeup && test_bit(EC_FLAGS_STARTED, &ec->flags) && 1957 ec->gpe >= 0 && ec->reference_count >= 1) 1958 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_DISABLE); 1959 1960 acpi_ec_enter_noirq(ec); 1961 1962 return 0; 1963 } 1964 1965 static int acpi_ec_resume_noirq(struct device *dev) 1966 { 1967 struct acpi_ec *ec = acpi_driver_data(to_acpi_device(dev)); 1968 1969 acpi_ec_leave_noirq(ec); 1970 1971 if (ec_no_wakeup && test_bit(EC_FLAGS_STARTED, &ec->flags) && 1972 ec->gpe >= 0 && ec->reference_count >= 1) 1973 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_ENABLE); 1974 1975 return 0; 1976 } 1977 1978 static int acpi_ec_resume(struct device *dev) 1979 { 1980 struct acpi_ec *ec = 1981 acpi_driver_data(to_acpi_device(dev)); 1982 1983 acpi_ec_enable_event(ec); 1984 return 0; 1985 } 1986 1987 void acpi_ec_mark_gpe_for_wake(void) 1988 { 1989 if (first_ec && !ec_no_wakeup) 1990 acpi_mark_gpe_for_wake(NULL, first_ec->gpe); 1991 } 1992 EXPORT_SYMBOL_GPL(acpi_ec_mark_gpe_for_wake); 1993 1994 void acpi_ec_set_gpe_wake_mask(u8 action) 1995 { 1996 if (pm_suspend_no_platform() && first_ec && !ec_no_wakeup) 1997 acpi_set_gpe_wake_mask(NULL, first_ec->gpe, action); 1998 } 1999 2000 bool acpi_ec_dispatch_gpe(void) 2001 { 2002 u32 ret; 2003 2004 if (!first_ec) 2005 return acpi_any_gpe_status_set(U32_MAX); 2006 2007 /* 2008 * Report wakeup if the status bit is set for any enabled GPE other 2009 * than the EC one. 2010 */ 2011 if (acpi_any_gpe_status_set(first_ec->gpe)) 2012 return true; 2013 2014 /* 2015 * Dispatch the EC GPE in-band, but do not report wakeup in any case 2016 * to allow the caller to process events properly after that. 2017 */ 2018 ret = acpi_dispatch_gpe(NULL, first_ec->gpe); 2019 if (ret == ACPI_INTERRUPT_HANDLED) 2020 pm_pr_dbg("ACPI EC GPE dispatched\n"); 2021 2022 /* Flush the event and query workqueues. */ 2023 acpi_ec_flush_work(); 2024 2025 return false; 2026 } 2027 #endif /* CONFIG_PM_SLEEP */ 2028 2029 static const struct dev_pm_ops acpi_ec_pm = { 2030 SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(acpi_ec_suspend_noirq, acpi_ec_resume_noirq) 2031 SET_SYSTEM_SLEEP_PM_OPS(acpi_ec_suspend, acpi_ec_resume) 2032 }; 2033 2034 static int param_set_event_clearing(const char *val, 2035 const struct kernel_param *kp) 2036 { 2037 int result = 0; 2038 2039 if (!strncmp(val, "status", sizeof("status") - 1)) { 2040 ec_event_clearing = ACPI_EC_EVT_TIMING_STATUS; 2041 pr_info("Assuming SCI_EVT clearing on EC_SC accesses\n"); 2042 } else if (!strncmp(val, "query", sizeof("query") - 1)) { 2043 ec_event_clearing = ACPI_EC_EVT_TIMING_QUERY; 2044 pr_info("Assuming SCI_EVT clearing on QR_EC writes\n"); 2045 } else if (!strncmp(val, "event", sizeof("event") - 1)) { 2046 ec_event_clearing = ACPI_EC_EVT_TIMING_EVENT; 2047 pr_info("Assuming SCI_EVT clearing on event reads\n"); 2048 } else 2049 result = -EINVAL; 2050 return result; 2051 } 2052 2053 static int param_get_event_clearing(char *buffer, 2054 const struct kernel_param *kp) 2055 { 2056 switch (ec_event_clearing) { 2057 case ACPI_EC_EVT_TIMING_STATUS: 2058 return sprintf(buffer, "status\n"); 2059 case ACPI_EC_EVT_TIMING_QUERY: 2060 return sprintf(buffer, "query\n"); 2061 case ACPI_EC_EVT_TIMING_EVENT: 2062 return sprintf(buffer, "event\n"); 2063 default: 2064 return sprintf(buffer, "invalid\n"); 2065 } 2066 return 0; 2067 } 2068 2069 module_param_call(ec_event_clearing, param_set_event_clearing, param_get_event_clearing, 2070 NULL, 0644); 2071 MODULE_PARM_DESC(ec_event_clearing, "Assumed SCI_EVT clearing timing"); 2072 2073 static struct acpi_driver acpi_ec_driver = { 2074 .name = "ec", 2075 .class = ACPI_EC_CLASS, 2076 .ids = ec_device_ids, 2077 .ops = { 2078 .add = acpi_ec_add, 2079 .remove = acpi_ec_remove, 2080 }, 2081 .drv.pm = &acpi_ec_pm, 2082 }; 2083 2084 static void acpi_ec_destroy_workqueues(void) 2085 { 2086 if (ec_wq) { 2087 destroy_workqueue(ec_wq); 2088 ec_wq = NULL; 2089 } 2090 if (ec_query_wq) { 2091 destroy_workqueue(ec_query_wq); 2092 ec_query_wq = NULL; 2093 } 2094 } 2095 2096 static int acpi_ec_init_workqueues(void) 2097 { 2098 if (!ec_wq) 2099 ec_wq = alloc_ordered_workqueue("kec", 0); 2100 2101 if (!ec_query_wq) 2102 ec_query_wq = alloc_workqueue("kec_query", 0, ec_max_queries); 2103 2104 if (!ec_wq || !ec_query_wq) { 2105 acpi_ec_destroy_workqueues(); 2106 return -ENODEV; 2107 } 2108 return 0; 2109 } 2110 2111 static const struct dmi_system_id acpi_ec_no_wakeup[] = { 2112 { 2113 .ident = "Thinkpad X1 Carbon 6th", 2114 .matches = { 2115 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"), 2116 DMI_MATCH(DMI_PRODUCT_FAMILY, "Thinkpad X1 Carbon 6th"), 2117 }, 2118 }, 2119 { 2120 .ident = "ThinkPad X1 Carbon 6th", 2121 .matches = { 2122 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"), 2123 DMI_MATCH(DMI_PRODUCT_FAMILY, "ThinkPad X1 Carbon 6th"), 2124 }, 2125 }, 2126 { 2127 .ident = "ThinkPad X1 Yoga 3rd", 2128 .matches = { 2129 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"), 2130 DMI_MATCH(DMI_PRODUCT_FAMILY, "ThinkPad X1 Yoga 3rd"), 2131 }, 2132 }, 2133 { }, 2134 }; 2135 2136 void __init acpi_ec_init(void) 2137 { 2138 int result; 2139 2140 result = acpi_ec_init_workqueues(); 2141 if (result) 2142 return; 2143 2144 /* 2145 * Disable EC wakeup on following systems to prevent periodic 2146 * wakeup from EC GPE. 2147 */ 2148 if (dmi_check_system(acpi_ec_no_wakeup)) { 2149 ec_no_wakeup = true; 2150 pr_debug("Disabling EC wakeup on suspend-to-idle\n"); 2151 } 2152 2153 /* Driver must be registered after acpi_ec_init_workqueues(). */ 2154 acpi_bus_register_driver(&acpi_ec_driver); 2155 2156 acpi_ec_ecdt_start(); 2157 } 2158 2159 /* EC driver currently not unloadable */ 2160 #if 0 2161 static void __exit acpi_ec_exit(void) 2162 { 2163 2164 acpi_bus_unregister_driver(&acpi_ec_driver); 2165 acpi_ec_destroy_workqueues(); 2166 } 2167 #endif /* 0 */ 2168