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_EVENT_HANDLER_INSTALLED, /* Event handler installed */ 96 EC_FLAGS_EC_HANDLER_INSTALLED, /* OpReg handler installed */ 97 EC_FLAGS_EC_REG_CALLED, /* OpReg ACPI _REG method called */ 98 EC_FLAGS_QUERY_METHODS_INSTALLED, /* _Qxx handlers installed */ 99 EC_FLAGS_STARTED, /* Driver is started */ 100 EC_FLAGS_STOPPED, /* Driver is stopped */ 101 EC_FLAGS_EVENTS_MASKED, /* Events masked */ 102 }; 103 104 #define ACPI_EC_COMMAND_POLL 0x01 /* Available for command byte */ 105 #define ACPI_EC_COMMAND_COMPLETE 0x02 /* Completed last byte */ 106 107 /* ec.c is compiled in acpi namespace so this shows up as acpi.ec_delay param */ 108 static unsigned int ec_delay __read_mostly = ACPI_EC_DELAY; 109 module_param(ec_delay, uint, 0644); 110 MODULE_PARM_DESC(ec_delay, "Timeout(ms) waited until an EC command completes"); 111 112 static unsigned int ec_max_queries __read_mostly = ACPI_EC_MAX_QUERIES; 113 module_param(ec_max_queries, uint, 0644); 114 MODULE_PARM_DESC(ec_max_queries, "Maximum parallel _Qxx evaluations"); 115 116 static bool ec_busy_polling __read_mostly; 117 module_param(ec_busy_polling, bool, 0644); 118 MODULE_PARM_DESC(ec_busy_polling, "Use busy polling to advance EC transaction"); 119 120 static unsigned int ec_polling_guard __read_mostly = ACPI_EC_UDELAY_POLL; 121 module_param(ec_polling_guard, uint, 0644); 122 MODULE_PARM_DESC(ec_polling_guard, "Guard time(us) between EC accesses in polling modes"); 123 124 static unsigned int ec_event_clearing __read_mostly = ACPI_EC_EVT_TIMING_QUERY; 125 126 /* 127 * If the number of false interrupts per one transaction exceeds 128 * this threshold, will think there is a GPE storm happened and 129 * will disable the GPE for normal transaction. 130 */ 131 static unsigned int ec_storm_threshold __read_mostly = 8; 132 module_param(ec_storm_threshold, uint, 0644); 133 MODULE_PARM_DESC(ec_storm_threshold, "Maxim false GPE numbers not considered as GPE storm"); 134 135 static bool ec_freeze_events __read_mostly; 136 module_param(ec_freeze_events, bool, 0644); 137 MODULE_PARM_DESC(ec_freeze_events, "Disabling event handling during suspend/resume"); 138 139 static bool ec_no_wakeup __read_mostly; 140 module_param(ec_no_wakeup, bool, 0644); 141 MODULE_PARM_DESC(ec_no_wakeup, "Do not wake up from suspend-to-idle"); 142 143 struct acpi_ec_query_handler { 144 struct list_head node; 145 acpi_ec_query_func func; 146 acpi_handle handle; 147 void *data; 148 u8 query_bit; 149 struct kref kref; 150 }; 151 152 struct transaction { 153 const u8 *wdata; 154 u8 *rdata; 155 unsigned short irq_count; 156 u8 command; 157 u8 wi; 158 u8 ri; 159 u8 wlen; 160 u8 rlen; 161 u8 flags; 162 }; 163 164 struct acpi_ec_query { 165 struct transaction transaction; 166 struct work_struct work; 167 struct acpi_ec_query_handler *handler; 168 struct acpi_ec *ec; 169 }; 170 171 static int acpi_ec_submit_query(struct acpi_ec *ec); 172 static void advance_transaction(struct acpi_ec *ec, bool interrupt); 173 static void acpi_ec_event_handler(struct work_struct *work); 174 175 struct acpi_ec *first_ec; 176 EXPORT_SYMBOL(first_ec); 177 178 static struct acpi_ec *boot_ec; 179 static bool boot_ec_is_ecdt; 180 static struct workqueue_struct *ec_wq; 181 static struct workqueue_struct *ec_query_wq; 182 183 static int EC_FLAGS_CORRECT_ECDT; /* Needs ECDT port address correction */ 184 static int EC_FLAGS_TRUST_DSDT_GPE; /* Needs DSDT GPE as correction setting */ 185 static int EC_FLAGS_CLEAR_ON_RESUME; /* Needs acpi_ec_clear() on boot/resume */ 186 187 /* -------------------------------------------------------------------------- 188 * Logging/Debugging 189 * -------------------------------------------------------------------------- */ 190 191 /* 192 * Splitters used by the developers to track the boundary of the EC 193 * handling processes. 194 */ 195 #ifdef DEBUG 196 #define EC_DBG_SEP " " 197 #define EC_DBG_DRV "+++++" 198 #define EC_DBG_STM "=====" 199 #define EC_DBG_REQ "*****" 200 #define EC_DBG_EVT "#####" 201 #else 202 #define EC_DBG_SEP "" 203 #define EC_DBG_DRV 204 #define EC_DBG_STM 205 #define EC_DBG_REQ 206 #define EC_DBG_EVT 207 #endif 208 209 #define ec_log_raw(fmt, ...) \ 210 pr_info(fmt "\n", ##__VA_ARGS__) 211 #define ec_dbg_raw(fmt, ...) \ 212 pr_debug(fmt "\n", ##__VA_ARGS__) 213 #define ec_log(filter, fmt, ...) \ 214 ec_log_raw(filter EC_DBG_SEP fmt EC_DBG_SEP filter, ##__VA_ARGS__) 215 #define ec_dbg(filter, fmt, ...) \ 216 ec_dbg_raw(filter EC_DBG_SEP fmt EC_DBG_SEP filter, ##__VA_ARGS__) 217 218 #define ec_log_drv(fmt, ...) \ 219 ec_log(EC_DBG_DRV, fmt, ##__VA_ARGS__) 220 #define ec_dbg_drv(fmt, ...) \ 221 ec_dbg(EC_DBG_DRV, fmt, ##__VA_ARGS__) 222 #define ec_dbg_stm(fmt, ...) \ 223 ec_dbg(EC_DBG_STM, fmt, ##__VA_ARGS__) 224 #define ec_dbg_req(fmt, ...) \ 225 ec_dbg(EC_DBG_REQ, fmt, ##__VA_ARGS__) 226 #define ec_dbg_evt(fmt, ...) \ 227 ec_dbg(EC_DBG_EVT, fmt, ##__VA_ARGS__) 228 #define ec_dbg_ref(ec, fmt, ...) \ 229 ec_dbg_raw("%lu: " fmt, ec->reference_count, ## __VA_ARGS__) 230 231 /* -------------------------------------------------------------------------- 232 * Device Flags 233 * -------------------------------------------------------------------------- */ 234 235 static bool acpi_ec_started(struct acpi_ec *ec) 236 { 237 return test_bit(EC_FLAGS_STARTED, &ec->flags) && 238 !test_bit(EC_FLAGS_STOPPED, &ec->flags); 239 } 240 241 static bool acpi_ec_event_enabled(struct acpi_ec *ec) 242 { 243 /* 244 * There is an OSPM early stage logic. During the early stages 245 * (boot/resume), OSPMs shouldn't enable the event handling, only 246 * the EC transactions are allowed to be performed. 247 */ 248 if (!test_bit(EC_FLAGS_QUERY_ENABLED, &ec->flags)) 249 return false; 250 /* 251 * However, disabling the event handling is experimental for late 252 * stage (suspend), and is controlled by the boot parameter of 253 * "ec_freeze_events": 254 * 1. true: The EC event handling is disabled before entering 255 * the noirq stage. 256 * 2. false: The EC event handling is automatically disabled as 257 * soon as the EC driver is stopped. 258 */ 259 if (ec_freeze_events) 260 return acpi_ec_started(ec); 261 else 262 return test_bit(EC_FLAGS_STARTED, &ec->flags); 263 } 264 265 static bool acpi_ec_flushed(struct acpi_ec *ec) 266 { 267 return ec->reference_count == 1; 268 } 269 270 /* -------------------------------------------------------------------------- 271 * EC Registers 272 * -------------------------------------------------------------------------- */ 273 274 static inline u8 acpi_ec_read_status(struct acpi_ec *ec) 275 { 276 u8 x = inb(ec->command_addr); 277 278 ec_dbg_raw("EC_SC(R) = 0x%2.2x " 279 "SCI_EVT=%d BURST=%d CMD=%d IBF=%d OBF=%d", 280 x, 281 !!(x & ACPI_EC_FLAG_SCI), 282 !!(x & ACPI_EC_FLAG_BURST), 283 !!(x & ACPI_EC_FLAG_CMD), 284 !!(x & ACPI_EC_FLAG_IBF), 285 !!(x & ACPI_EC_FLAG_OBF)); 286 return x; 287 } 288 289 static inline u8 acpi_ec_read_data(struct acpi_ec *ec) 290 { 291 u8 x = inb(ec->data_addr); 292 293 ec->timestamp = jiffies; 294 ec_dbg_raw("EC_DATA(R) = 0x%2.2x", x); 295 return x; 296 } 297 298 static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command) 299 { 300 ec_dbg_raw("EC_SC(W) = 0x%2.2x", command); 301 outb(command, ec->command_addr); 302 ec->timestamp = jiffies; 303 } 304 305 static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data) 306 { 307 ec_dbg_raw("EC_DATA(W) = 0x%2.2x", data); 308 outb(data, ec->data_addr); 309 ec->timestamp = jiffies; 310 } 311 312 #if defined(DEBUG) || defined(CONFIG_DYNAMIC_DEBUG) 313 static const char *acpi_ec_cmd_string(u8 cmd) 314 { 315 switch (cmd) { 316 case 0x80: 317 return "RD_EC"; 318 case 0x81: 319 return "WR_EC"; 320 case 0x82: 321 return "BE_EC"; 322 case 0x83: 323 return "BD_EC"; 324 case 0x84: 325 return "QR_EC"; 326 } 327 return "UNKNOWN"; 328 } 329 #else 330 #define acpi_ec_cmd_string(cmd) "UNDEF" 331 #endif 332 333 /* -------------------------------------------------------------------------- 334 * GPE Registers 335 * -------------------------------------------------------------------------- */ 336 337 static inline bool acpi_ec_gpe_status_set(struct acpi_ec *ec) 338 { 339 acpi_event_status gpe_status = 0; 340 341 (void)acpi_get_gpe_status(NULL, ec->gpe, &gpe_status); 342 return !!(gpe_status & ACPI_EVENT_FLAG_STATUS_SET); 343 } 344 345 static inline void acpi_ec_enable_gpe(struct acpi_ec *ec, bool open) 346 { 347 if (open) 348 acpi_enable_gpe(NULL, ec->gpe); 349 else { 350 BUG_ON(ec->reference_count < 1); 351 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_ENABLE); 352 } 353 if (acpi_ec_gpe_status_set(ec)) { 354 /* 355 * On some platforms, EN=1 writes cannot trigger GPE. So 356 * software need to manually trigger a pseudo GPE event on 357 * EN=1 writes. 358 */ 359 ec_dbg_raw("Polling quirk"); 360 advance_transaction(ec, false); 361 } 362 } 363 364 static inline void acpi_ec_disable_gpe(struct acpi_ec *ec, bool close) 365 { 366 if (close) 367 acpi_disable_gpe(NULL, ec->gpe); 368 else { 369 BUG_ON(ec->reference_count < 1); 370 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_DISABLE); 371 } 372 } 373 374 /* -------------------------------------------------------------------------- 375 * Transaction Management 376 * -------------------------------------------------------------------------- */ 377 378 static void acpi_ec_submit_request(struct acpi_ec *ec) 379 { 380 ec->reference_count++; 381 if (test_bit(EC_FLAGS_EVENT_HANDLER_INSTALLED, &ec->flags) && 382 ec->gpe >= 0 && ec->reference_count == 1) 383 acpi_ec_enable_gpe(ec, true); 384 } 385 386 static void acpi_ec_complete_request(struct acpi_ec *ec) 387 { 388 bool flushed = false; 389 390 ec->reference_count--; 391 if (test_bit(EC_FLAGS_EVENT_HANDLER_INSTALLED, &ec->flags) && 392 ec->gpe >= 0 && ec->reference_count == 0) 393 acpi_ec_disable_gpe(ec, true); 394 flushed = acpi_ec_flushed(ec); 395 if (flushed) 396 wake_up(&ec->wait); 397 } 398 399 static void acpi_ec_mask_events(struct acpi_ec *ec) 400 { 401 if (!test_bit(EC_FLAGS_EVENTS_MASKED, &ec->flags)) { 402 if (ec->gpe >= 0) 403 acpi_ec_disable_gpe(ec, false); 404 else 405 disable_irq_nosync(ec->irq); 406 407 ec_dbg_drv("Polling enabled"); 408 set_bit(EC_FLAGS_EVENTS_MASKED, &ec->flags); 409 } 410 } 411 412 static void acpi_ec_unmask_events(struct acpi_ec *ec) 413 { 414 if (test_bit(EC_FLAGS_EVENTS_MASKED, &ec->flags)) { 415 clear_bit(EC_FLAGS_EVENTS_MASKED, &ec->flags); 416 if (ec->gpe >= 0) 417 acpi_ec_enable_gpe(ec, false); 418 else 419 enable_irq(ec->irq); 420 421 ec_dbg_drv("Polling disabled"); 422 } 423 } 424 425 /* 426 * acpi_ec_submit_flushable_request() - Increase the reference count unless 427 * the flush operation is not in 428 * progress 429 * @ec: the EC device 430 * 431 * This function must be used before taking a new action that should hold 432 * the reference count. If this function returns false, then the action 433 * must be discarded or it will prevent the flush operation from being 434 * completed. 435 */ 436 static bool acpi_ec_submit_flushable_request(struct acpi_ec *ec) 437 { 438 if (!acpi_ec_started(ec)) 439 return false; 440 acpi_ec_submit_request(ec); 441 return true; 442 } 443 444 static void acpi_ec_submit_event(struct acpi_ec *ec) 445 { 446 /* 447 * It is safe to mask the events here, because acpi_ec_close_event() 448 * will run at least once after this. 449 */ 450 acpi_ec_mask_events(ec); 451 if (!acpi_ec_event_enabled(ec)) 452 return; 453 454 if (ec->event_state != EC_EVENT_READY) 455 return; 456 457 ec_dbg_evt("Command(%s) submitted/blocked", 458 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY)); 459 460 ec->event_state = EC_EVENT_IN_PROGRESS; 461 /* 462 * If events_to_process is greater than 0 at this point, the while () 463 * loop in acpi_ec_event_handler() is still running and incrementing 464 * events_to_process will cause it to invoke acpi_ec_submit_query() once 465 * more, so it is not necessary to queue up the event work to start the 466 * same loop again. 467 */ 468 if (ec->events_to_process++ > 0) 469 return; 470 471 ec->events_in_progress++; 472 queue_work(ec_wq, &ec->work); 473 } 474 475 static void acpi_ec_complete_event(struct acpi_ec *ec) 476 { 477 if (ec->event_state == EC_EVENT_IN_PROGRESS) 478 ec->event_state = EC_EVENT_COMPLETE; 479 } 480 481 static void acpi_ec_close_event(struct acpi_ec *ec) 482 { 483 if (ec->event_state != EC_EVENT_READY) 484 ec_dbg_evt("Command(%s) unblocked", 485 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY)); 486 487 ec->event_state = EC_EVENT_READY; 488 acpi_ec_unmask_events(ec); 489 } 490 491 static inline void __acpi_ec_enable_event(struct acpi_ec *ec) 492 { 493 if (!test_and_set_bit(EC_FLAGS_QUERY_ENABLED, &ec->flags)) 494 ec_log_drv("event unblocked"); 495 /* 496 * Unconditionally invoke this once after enabling the event 497 * handling mechanism to detect the pending events. 498 */ 499 advance_transaction(ec, false); 500 } 501 502 static inline void __acpi_ec_disable_event(struct acpi_ec *ec) 503 { 504 if (test_and_clear_bit(EC_FLAGS_QUERY_ENABLED, &ec->flags)) 505 ec_log_drv("event blocked"); 506 } 507 508 /* 509 * Process _Q events that might have accumulated in the EC. 510 * Run with locked ec mutex. 511 */ 512 static void acpi_ec_clear(struct acpi_ec *ec) 513 { 514 int i; 515 516 for (i = 0; i < ACPI_EC_CLEAR_MAX; i++) { 517 if (acpi_ec_submit_query(ec)) 518 break; 519 } 520 if (unlikely(i == ACPI_EC_CLEAR_MAX)) 521 pr_warn("Warning: Maximum of %d stale EC events cleared\n", i); 522 else 523 pr_info("%d stale EC events cleared\n", i); 524 } 525 526 static void acpi_ec_enable_event(struct acpi_ec *ec) 527 { 528 unsigned long flags; 529 530 spin_lock_irqsave(&ec->lock, flags); 531 if (acpi_ec_started(ec)) 532 __acpi_ec_enable_event(ec); 533 spin_unlock_irqrestore(&ec->lock, flags); 534 535 /* Drain additional events if hardware requires that */ 536 if (EC_FLAGS_CLEAR_ON_RESUME) 537 acpi_ec_clear(ec); 538 } 539 540 #ifdef CONFIG_PM_SLEEP 541 static void __acpi_ec_flush_work(void) 542 { 543 flush_workqueue(ec_wq); /* flush ec->work */ 544 flush_workqueue(ec_query_wq); /* flush queries */ 545 } 546 547 static void acpi_ec_disable_event(struct acpi_ec *ec) 548 { 549 unsigned long flags; 550 551 spin_lock_irqsave(&ec->lock, flags); 552 __acpi_ec_disable_event(ec); 553 spin_unlock_irqrestore(&ec->lock, flags); 554 555 /* 556 * When ec_freeze_events is true, we need to flush events in 557 * the proper position before entering the noirq stage. 558 */ 559 __acpi_ec_flush_work(); 560 } 561 562 void acpi_ec_flush_work(void) 563 { 564 /* Without ec_wq there is nothing to flush. */ 565 if (!ec_wq) 566 return; 567 568 __acpi_ec_flush_work(); 569 } 570 #endif /* CONFIG_PM_SLEEP */ 571 572 static bool acpi_ec_guard_event(struct acpi_ec *ec) 573 { 574 unsigned long flags; 575 bool guarded; 576 577 spin_lock_irqsave(&ec->lock, flags); 578 /* 579 * If firmware SCI_EVT clearing timing is "event", we actually 580 * don't know when the SCI_EVT will be cleared by firmware after 581 * evaluating _Qxx, so we need to re-check SCI_EVT after waiting an 582 * acceptable period. 583 * 584 * The guarding period is applicable if the event state is not 585 * EC_EVENT_READY, but otherwise if the current transaction is of the 586 * ACPI_EC_COMMAND_QUERY type, the guarding should have elapsed already 587 * and it should not be applied to let the transaction transition into 588 * the ACPI_EC_COMMAND_POLL state immediately. 589 */ 590 guarded = ec_event_clearing == ACPI_EC_EVT_TIMING_EVENT && 591 ec->event_state != EC_EVENT_READY && 592 (!ec->curr || ec->curr->command != ACPI_EC_COMMAND_QUERY); 593 spin_unlock_irqrestore(&ec->lock, flags); 594 return guarded; 595 } 596 597 static int ec_transaction_polled(struct acpi_ec *ec) 598 { 599 unsigned long flags; 600 int ret = 0; 601 602 spin_lock_irqsave(&ec->lock, flags); 603 if (ec->curr && (ec->curr->flags & ACPI_EC_COMMAND_POLL)) 604 ret = 1; 605 spin_unlock_irqrestore(&ec->lock, flags); 606 return ret; 607 } 608 609 static int ec_transaction_completed(struct acpi_ec *ec) 610 { 611 unsigned long flags; 612 int ret = 0; 613 614 spin_lock_irqsave(&ec->lock, flags); 615 if (ec->curr && (ec->curr->flags & ACPI_EC_COMMAND_COMPLETE)) 616 ret = 1; 617 spin_unlock_irqrestore(&ec->lock, flags); 618 return ret; 619 } 620 621 static inline void ec_transaction_transition(struct acpi_ec *ec, unsigned long flag) 622 { 623 ec->curr->flags |= flag; 624 625 if (ec->curr->command != ACPI_EC_COMMAND_QUERY) 626 return; 627 628 switch (ec_event_clearing) { 629 case ACPI_EC_EVT_TIMING_STATUS: 630 if (flag == ACPI_EC_COMMAND_POLL) 631 acpi_ec_close_event(ec); 632 633 return; 634 635 case ACPI_EC_EVT_TIMING_QUERY: 636 if (flag == ACPI_EC_COMMAND_COMPLETE) 637 acpi_ec_close_event(ec); 638 639 return; 640 641 case ACPI_EC_EVT_TIMING_EVENT: 642 if (flag == ACPI_EC_COMMAND_COMPLETE) 643 acpi_ec_complete_event(ec); 644 } 645 } 646 647 static void acpi_ec_spurious_interrupt(struct acpi_ec *ec, struct transaction *t) 648 { 649 if (t->irq_count < ec_storm_threshold) 650 ++t->irq_count; 651 652 /* Trigger if the threshold is 0 too. */ 653 if (t->irq_count == ec_storm_threshold) 654 acpi_ec_mask_events(ec); 655 } 656 657 static void advance_transaction(struct acpi_ec *ec, bool interrupt) 658 { 659 struct transaction *t = ec->curr; 660 bool wakeup = false; 661 u8 status; 662 663 ec_dbg_stm("%s (%d)", interrupt ? "IRQ" : "TASK", smp_processor_id()); 664 665 status = acpi_ec_read_status(ec); 666 667 /* 668 * Another IRQ or a guarded polling mode advancement is detected, 669 * the next QR_EC submission is then allowed. 670 */ 671 if (!t || !(t->flags & ACPI_EC_COMMAND_POLL)) { 672 if (ec_event_clearing == ACPI_EC_EVT_TIMING_EVENT && 673 ec->event_state == EC_EVENT_COMPLETE) 674 acpi_ec_close_event(ec); 675 676 if (!t) 677 goto out; 678 } 679 680 if (t->flags & ACPI_EC_COMMAND_POLL) { 681 if (t->wlen > t->wi) { 682 if (!(status & ACPI_EC_FLAG_IBF)) 683 acpi_ec_write_data(ec, t->wdata[t->wi++]); 684 else if (interrupt && !(status & ACPI_EC_FLAG_SCI)) 685 acpi_ec_spurious_interrupt(ec, t); 686 } else if (t->rlen > t->ri) { 687 if (status & ACPI_EC_FLAG_OBF) { 688 t->rdata[t->ri++] = acpi_ec_read_data(ec); 689 if (t->rlen == t->ri) { 690 ec_transaction_transition(ec, ACPI_EC_COMMAND_COMPLETE); 691 wakeup = true; 692 if (t->command == ACPI_EC_COMMAND_QUERY) 693 ec_dbg_evt("Command(%s) completed by hardware", 694 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY)); 695 } 696 } else if (interrupt && !(status & ACPI_EC_FLAG_SCI)) { 697 acpi_ec_spurious_interrupt(ec, t); 698 } 699 } else if (t->wlen == t->wi && !(status & ACPI_EC_FLAG_IBF)) { 700 ec_transaction_transition(ec, ACPI_EC_COMMAND_COMPLETE); 701 wakeup = true; 702 } 703 } else if (!(status & ACPI_EC_FLAG_IBF)) { 704 acpi_ec_write_cmd(ec, t->command); 705 ec_transaction_transition(ec, ACPI_EC_COMMAND_POLL); 706 } 707 708 out: 709 if (status & ACPI_EC_FLAG_SCI) 710 acpi_ec_submit_event(ec); 711 712 if (wakeup && interrupt) 713 wake_up(&ec->wait); 714 } 715 716 static void start_transaction(struct acpi_ec *ec) 717 { 718 ec->curr->irq_count = ec->curr->wi = ec->curr->ri = 0; 719 ec->curr->flags = 0; 720 } 721 722 static int ec_guard(struct acpi_ec *ec) 723 { 724 unsigned long guard = usecs_to_jiffies(ec->polling_guard); 725 unsigned long timeout = ec->timestamp + guard; 726 727 /* Ensure guarding period before polling EC status */ 728 do { 729 if (ec->busy_polling) { 730 /* Perform busy polling */ 731 if (ec_transaction_completed(ec)) 732 return 0; 733 udelay(jiffies_to_usecs(guard)); 734 } else { 735 /* 736 * Perform wait polling 737 * 1. Wait the transaction to be completed by the 738 * GPE handler after the transaction enters 739 * ACPI_EC_COMMAND_POLL state. 740 * 2. A special guarding logic is also required 741 * for event clearing mode "event" before the 742 * transaction enters ACPI_EC_COMMAND_POLL 743 * state. 744 */ 745 if (!ec_transaction_polled(ec) && 746 !acpi_ec_guard_event(ec)) 747 break; 748 if (wait_event_timeout(ec->wait, 749 ec_transaction_completed(ec), 750 guard)) 751 return 0; 752 } 753 } while (time_before(jiffies, timeout)); 754 return -ETIME; 755 } 756 757 static int ec_poll(struct acpi_ec *ec) 758 { 759 unsigned long flags; 760 int repeat = 5; /* number of command restarts */ 761 762 while (repeat--) { 763 unsigned long delay = jiffies + 764 msecs_to_jiffies(ec_delay); 765 do { 766 if (!ec_guard(ec)) 767 return 0; 768 spin_lock_irqsave(&ec->lock, flags); 769 advance_transaction(ec, false); 770 spin_unlock_irqrestore(&ec->lock, flags); 771 } while (time_before(jiffies, delay)); 772 pr_debug("controller reset, restart transaction\n"); 773 spin_lock_irqsave(&ec->lock, flags); 774 start_transaction(ec); 775 spin_unlock_irqrestore(&ec->lock, flags); 776 } 777 return -ETIME; 778 } 779 780 static int acpi_ec_transaction_unlocked(struct acpi_ec *ec, 781 struct transaction *t) 782 { 783 unsigned long tmp; 784 int ret = 0; 785 786 /* start transaction */ 787 spin_lock_irqsave(&ec->lock, tmp); 788 /* Enable GPE for command processing (IBF=0/OBF=1) */ 789 if (!acpi_ec_submit_flushable_request(ec)) { 790 ret = -EINVAL; 791 goto unlock; 792 } 793 ec_dbg_ref(ec, "Increase command"); 794 /* following two actions should be kept atomic */ 795 ec->curr = t; 796 ec_dbg_req("Command(%s) started", acpi_ec_cmd_string(t->command)); 797 start_transaction(ec); 798 spin_unlock_irqrestore(&ec->lock, tmp); 799 800 ret = ec_poll(ec); 801 802 spin_lock_irqsave(&ec->lock, tmp); 803 if (t->irq_count == ec_storm_threshold) 804 acpi_ec_unmask_events(ec); 805 ec_dbg_req("Command(%s) stopped", acpi_ec_cmd_string(t->command)); 806 ec->curr = NULL; 807 /* Disable GPE for command processing (IBF=0/OBF=1) */ 808 acpi_ec_complete_request(ec); 809 ec_dbg_ref(ec, "Decrease command"); 810 unlock: 811 spin_unlock_irqrestore(&ec->lock, tmp); 812 return ret; 813 } 814 815 static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t) 816 { 817 int status; 818 u32 glk; 819 820 if (!ec || (!t) || (t->wlen && !t->wdata) || (t->rlen && !t->rdata)) 821 return -EINVAL; 822 if (t->rdata) 823 memset(t->rdata, 0, t->rlen); 824 825 mutex_lock(&ec->mutex); 826 if (ec->global_lock) { 827 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk); 828 if (ACPI_FAILURE(status)) { 829 status = -ENODEV; 830 goto unlock; 831 } 832 } 833 834 status = acpi_ec_transaction_unlocked(ec, t); 835 836 if (ec->global_lock) 837 acpi_release_global_lock(glk); 838 unlock: 839 mutex_unlock(&ec->mutex); 840 return status; 841 } 842 843 static int acpi_ec_burst_enable(struct acpi_ec *ec) 844 { 845 u8 d; 846 struct transaction t = {.command = ACPI_EC_BURST_ENABLE, 847 .wdata = NULL, .rdata = &d, 848 .wlen = 0, .rlen = 1}; 849 850 return acpi_ec_transaction(ec, &t); 851 } 852 853 static int acpi_ec_burst_disable(struct acpi_ec *ec) 854 { 855 struct transaction t = {.command = ACPI_EC_BURST_DISABLE, 856 .wdata = NULL, .rdata = NULL, 857 .wlen = 0, .rlen = 0}; 858 859 return (acpi_ec_read_status(ec) & ACPI_EC_FLAG_BURST) ? 860 acpi_ec_transaction(ec, &t) : 0; 861 } 862 863 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 *data) 864 { 865 int result; 866 u8 d; 867 struct transaction t = {.command = ACPI_EC_COMMAND_READ, 868 .wdata = &address, .rdata = &d, 869 .wlen = 1, .rlen = 1}; 870 871 result = acpi_ec_transaction(ec, &t); 872 *data = d; 873 return result; 874 } 875 876 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data) 877 { 878 u8 wdata[2] = { address, data }; 879 struct transaction t = {.command = ACPI_EC_COMMAND_WRITE, 880 .wdata = wdata, .rdata = NULL, 881 .wlen = 2, .rlen = 0}; 882 883 return acpi_ec_transaction(ec, &t); 884 } 885 886 int ec_read(u8 addr, u8 *val) 887 { 888 int err; 889 u8 temp_data; 890 891 if (!first_ec) 892 return -ENODEV; 893 894 err = acpi_ec_read(first_ec, addr, &temp_data); 895 896 if (!err) { 897 *val = temp_data; 898 return 0; 899 } 900 return err; 901 } 902 EXPORT_SYMBOL(ec_read); 903 904 int ec_write(u8 addr, u8 val) 905 { 906 if (!first_ec) 907 return -ENODEV; 908 909 return acpi_ec_write(first_ec, addr, val); 910 } 911 EXPORT_SYMBOL(ec_write); 912 913 int ec_transaction(u8 command, 914 const u8 *wdata, unsigned wdata_len, 915 u8 *rdata, unsigned rdata_len) 916 { 917 struct transaction t = {.command = command, 918 .wdata = wdata, .rdata = rdata, 919 .wlen = wdata_len, .rlen = rdata_len}; 920 921 if (!first_ec) 922 return -ENODEV; 923 924 return acpi_ec_transaction(first_ec, &t); 925 } 926 EXPORT_SYMBOL(ec_transaction); 927 928 /* Get the handle to the EC device */ 929 acpi_handle ec_get_handle(void) 930 { 931 if (!first_ec) 932 return NULL; 933 return first_ec->handle; 934 } 935 EXPORT_SYMBOL(ec_get_handle); 936 937 static void acpi_ec_start(struct acpi_ec *ec, bool resuming) 938 { 939 unsigned long flags; 940 941 spin_lock_irqsave(&ec->lock, flags); 942 if (!test_and_set_bit(EC_FLAGS_STARTED, &ec->flags)) { 943 ec_dbg_drv("Starting EC"); 944 /* Enable GPE for event processing (SCI_EVT=1) */ 945 if (!resuming) { 946 acpi_ec_submit_request(ec); 947 ec_dbg_ref(ec, "Increase driver"); 948 } 949 ec_log_drv("EC started"); 950 } 951 spin_unlock_irqrestore(&ec->lock, flags); 952 } 953 954 static bool acpi_ec_stopped(struct acpi_ec *ec) 955 { 956 unsigned long flags; 957 bool flushed; 958 959 spin_lock_irqsave(&ec->lock, flags); 960 flushed = acpi_ec_flushed(ec); 961 spin_unlock_irqrestore(&ec->lock, flags); 962 return flushed; 963 } 964 965 static void acpi_ec_stop(struct acpi_ec *ec, bool suspending) 966 { 967 unsigned long flags; 968 969 spin_lock_irqsave(&ec->lock, flags); 970 if (acpi_ec_started(ec)) { 971 ec_dbg_drv("Stopping EC"); 972 set_bit(EC_FLAGS_STOPPED, &ec->flags); 973 spin_unlock_irqrestore(&ec->lock, flags); 974 wait_event(ec->wait, acpi_ec_stopped(ec)); 975 spin_lock_irqsave(&ec->lock, flags); 976 /* Disable GPE for event processing (SCI_EVT=1) */ 977 if (!suspending) { 978 acpi_ec_complete_request(ec); 979 ec_dbg_ref(ec, "Decrease driver"); 980 } else if (!ec_freeze_events) 981 __acpi_ec_disable_event(ec); 982 clear_bit(EC_FLAGS_STARTED, &ec->flags); 983 clear_bit(EC_FLAGS_STOPPED, &ec->flags); 984 ec_log_drv("EC stopped"); 985 } 986 spin_unlock_irqrestore(&ec->lock, flags); 987 } 988 989 static void acpi_ec_enter_noirq(struct acpi_ec *ec) 990 { 991 unsigned long flags; 992 993 spin_lock_irqsave(&ec->lock, flags); 994 ec->busy_polling = true; 995 ec->polling_guard = 0; 996 ec_log_drv("interrupt blocked"); 997 spin_unlock_irqrestore(&ec->lock, flags); 998 } 999 1000 static void acpi_ec_leave_noirq(struct acpi_ec *ec) 1001 { 1002 unsigned long flags; 1003 1004 spin_lock_irqsave(&ec->lock, flags); 1005 ec->busy_polling = ec_busy_polling; 1006 ec->polling_guard = ec_polling_guard; 1007 ec_log_drv("interrupt unblocked"); 1008 spin_unlock_irqrestore(&ec->lock, flags); 1009 } 1010 1011 void acpi_ec_block_transactions(void) 1012 { 1013 struct acpi_ec *ec = first_ec; 1014 1015 if (!ec) 1016 return; 1017 1018 mutex_lock(&ec->mutex); 1019 /* Prevent transactions from being carried out */ 1020 acpi_ec_stop(ec, true); 1021 mutex_unlock(&ec->mutex); 1022 } 1023 1024 void acpi_ec_unblock_transactions(void) 1025 { 1026 /* 1027 * Allow transactions to happen again (this function is called from 1028 * atomic context during wakeup, so we don't need to acquire the mutex). 1029 */ 1030 if (first_ec) 1031 acpi_ec_start(first_ec, true); 1032 } 1033 1034 /* -------------------------------------------------------------------------- 1035 Event Management 1036 -------------------------------------------------------------------------- */ 1037 static struct acpi_ec_query_handler * 1038 acpi_ec_get_query_handler_by_value(struct acpi_ec *ec, u8 value) 1039 { 1040 struct acpi_ec_query_handler *handler; 1041 1042 mutex_lock(&ec->mutex); 1043 list_for_each_entry(handler, &ec->list, node) { 1044 if (value == handler->query_bit) { 1045 kref_get(&handler->kref); 1046 mutex_unlock(&ec->mutex); 1047 return handler; 1048 } 1049 } 1050 mutex_unlock(&ec->mutex); 1051 return NULL; 1052 } 1053 1054 static void acpi_ec_query_handler_release(struct kref *kref) 1055 { 1056 struct acpi_ec_query_handler *handler = 1057 container_of(kref, struct acpi_ec_query_handler, kref); 1058 1059 kfree(handler); 1060 } 1061 1062 static void acpi_ec_put_query_handler(struct acpi_ec_query_handler *handler) 1063 { 1064 kref_put(&handler->kref, acpi_ec_query_handler_release); 1065 } 1066 1067 int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit, 1068 acpi_handle handle, acpi_ec_query_func func, 1069 void *data) 1070 { 1071 struct acpi_ec_query_handler *handler; 1072 1073 if (!handle && !func) 1074 return -EINVAL; 1075 1076 handler = kzalloc(sizeof(*handler), GFP_KERNEL); 1077 if (!handler) 1078 return -ENOMEM; 1079 1080 handler->query_bit = query_bit; 1081 handler->handle = handle; 1082 handler->func = func; 1083 handler->data = data; 1084 mutex_lock(&ec->mutex); 1085 kref_init(&handler->kref); 1086 list_add(&handler->node, &ec->list); 1087 mutex_unlock(&ec->mutex); 1088 1089 return 0; 1090 } 1091 EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler); 1092 1093 static void acpi_ec_remove_query_handlers(struct acpi_ec *ec, 1094 bool remove_all, u8 query_bit) 1095 { 1096 struct acpi_ec_query_handler *handler, *tmp; 1097 LIST_HEAD(free_list); 1098 1099 mutex_lock(&ec->mutex); 1100 list_for_each_entry_safe(handler, tmp, &ec->list, node) { 1101 /* 1102 * When remove_all is false, only remove custom query handlers 1103 * which have handler->func set. This is done to preserve query 1104 * handlers discovered thru ACPI, as they should continue handling 1105 * EC queries. 1106 */ 1107 if (remove_all || (handler->func && handler->query_bit == query_bit)) { 1108 list_del_init(&handler->node); 1109 list_add(&handler->node, &free_list); 1110 1111 } 1112 } 1113 mutex_unlock(&ec->mutex); 1114 list_for_each_entry_safe(handler, tmp, &free_list, node) 1115 acpi_ec_put_query_handler(handler); 1116 } 1117 1118 void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit) 1119 { 1120 acpi_ec_remove_query_handlers(ec, false, query_bit); 1121 flush_workqueue(ec_query_wq); 1122 } 1123 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler); 1124 1125 static void acpi_ec_event_processor(struct work_struct *work) 1126 { 1127 struct acpi_ec_query *q = container_of(work, struct acpi_ec_query, work); 1128 struct acpi_ec_query_handler *handler = q->handler; 1129 struct acpi_ec *ec = q->ec; 1130 1131 ec_dbg_evt("Query(0x%02x) started", handler->query_bit); 1132 1133 if (handler->func) 1134 handler->func(handler->data); 1135 else if (handler->handle) 1136 acpi_evaluate_object(handler->handle, NULL, NULL, NULL); 1137 1138 ec_dbg_evt("Query(0x%02x) stopped", handler->query_bit); 1139 1140 spin_lock_irq(&ec->lock); 1141 ec->queries_in_progress--; 1142 spin_unlock_irq(&ec->lock); 1143 1144 acpi_ec_put_query_handler(handler); 1145 kfree(q); 1146 } 1147 1148 static struct acpi_ec_query *acpi_ec_create_query(struct acpi_ec *ec, u8 *pval) 1149 { 1150 struct acpi_ec_query *q; 1151 struct transaction *t; 1152 1153 q = kzalloc(sizeof (struct acpi_ec_query), GFP_KERNEL); 1154 if (!q) 1155 return NULL; 1156 1157 INIT_WORK(&q->work, acpi_ec_event_processor); 1158 t = &q->transaction; 1159 t->command = ACPI_EC_COMMAND_QUERY; 1160 t->rdata = pval; 1161 t->rlen = 1; 1162 q->ec = ec; 1163 return q; 1164 } 1165 1166 static int acpi_ec_submit_query(struct acpi_ec *ec) 1167 { 1168 struct acpi_ec_query *q; 1169 u8 value = 0; 1170 int result; 1171 1172 q = acpi_ec_create_query(ec, &value); 1173 if (!q) 1174 return -ENOMEM; 1175 1176 /* 1177 * Query the EC to find out which _Qxx method we need to evaluate. 1178 * Note that successful completion of the query causes the ACPI_EC_SCI 1179 * bit to be cleared (and thus clearing the interrupt source). 1180 */ 1181 result = acpi_ec_transaction(ec, &q->transaction); 1182 if (result) 1183 goto err_exit; 1184 1185 if (!value) { 1186 result = -ENODATA; 1187 goto err_exit; 1188 } 1189 1190 q->handler = acpi_ec_get_query_handler_by_value(ec, value); 1191 if (!q->handler) { 1192 result = -ENODATA; 1193 goto err_exit; 1194 } 1195 1196 /* 1197 * It is reported that _Qxx are evaluated in a parallel way on Windows: 1198 * https://bugzilla.kernel.org/show_bug.cgi?id=94411 1199 * 1200 * Put this log entry before queue_work() to make it appear in the log 1201 * before any other messages emitted during workqueue handling. 1202 */ 1203 ec_dbg_evt("Query(0x%02x) scheduled", value); 1204 1205 spin_lock_irq(&ec->lock); 1206 1207 ec->queries_in_progress++; 1208 queue_work(ec_query_wq, &q->work); 1209 1210 spin_unlock_irq(&ec->lock); 1211 1212 return 0; 1213 1214 err_exit: 1215 kfree(q); 1216 1217 return result; 1218 } 1219 1220 static void acpi_ec_event_handler(struct work_struct *work) 1221 { 1222 struct acpi_ec *ec = container_of(work, struct acpi_ec, work); 1223 1224 ec_dbg_evt("Event started"); 1225 1226 spin_lock_irq(&ec->lock); 1227 1228 while (ec->events_to_process) { 1229 spin_unlock_irq(&ec->lock); 1230 1231 acpi_ec_submit_query(ec); 1232 1233 spin_lock_irq(&ec->lock); 1234 1235 ec->events_to_process--; 1236 } 1237 1238 /* 1239 * Before exit, make sure that the it will be possible to queue up the 1240 * event handling work again regardless of whether or not the query 1241 * queued up above is processed successfully. 1242 */ 1243 if (ec_event_clearing == ACPI_EC_EVT_TIMING_EVENT) { 1244 bool guard_timeout; 1245 1246 acpi_ec_complete_event(ec); 1247 1248 ec_dbg_evt("Event stopped"); 1249 1250 spin_unlock_irq(&ec->lock); 1251 1252 guard_timeout = !!ec_guard(ec); 1253 1254 spin_lock_irq(&ec->lock); 1255 1256 /* Take care of SCI_EVT unless someone else is doing that. */ 1257 if (guard_timeout && !ec->curr) 1258 advance_transaction(ec, false); 1259 } else { 1260 acpi_ec_close_event(ec); 1261 1262 ec_dbg_evt("Event stopped"); 1263 } 1264 1265 ec->events_in_progress--; 1266 1267 spin_unlock_irq(&ec->lock); 1268 } 1269 1270 static void clear_gpe_and_advance_transaction(struct acpi_ec *ec, bool interrupt) 1271 { 1272 /* 1273 * Clear GPE_STS upfront to allow subsequent hardware GPE_STS 0->1 1274 * changes to always trigger a GPE interrupt. 1275 * 1276 * GPE STS is a W1C register, which means: 1277 * 1278 * 1. Software can clear it without worrying about clearing the other 1279 * GPEs' STS bits when the hardware sets them in parallel. 1280 * 1281 * 2. As long as software can ensure only clearing it when it is set, 1282 * hardware won't set it in parallel. 1283 */ 1284 if (ec->gpe >= 0 && acpi_ec_gpe_status_set(ec)) 1285 acpi_clear_gpe(NULL, ec->gpe); 1286 1287 advance_transaction(ec, true); 1288 } 1289 1290 static void acpi_ec_handle_interrupt(struct acpi_ec *ec) 1291 { 1292 unsigned long flags; 1293 1294 spin_lock_irqsave(&ec->lock, flags); 1295 1296 clear_gpe_and_advance_transaction(ec, true); 1297 1298 spin_unlock_irqrestore(&ec->lock, flags); 1299 } 1300 1301 static u32 acpi_ec_gpe_handler(acpi_handle gpe_device, 1302 u32 gpe_number, void *data) 1303 { 1304 acpi_ec_handle_interrupt(data); 1305 return ACPI_INTERRUPT_HANDLED; 1306 } 1307 1308 static irqreturn_t acpi_ec_irq_handler(int irq, void *data) 1309 { 1310 acpi_ec_handle_interrupt(data); 1311 return IRQ_HANDLED; 1312 } 1313 1314 /* -------------------------------------------------------------------------- 1315 * Address Space Management 1316 * -------------------------------------------------------------------------- */ 1317 1318 static acpi_status 1319 acpi_ec_space_handler(u32 function, acpi_physical_address address, 1320 u32 bits, u64 *value64, 1321 void *handler_context, void *region_context) 1322 { 1323 struct acpi_ec *ec = handler_context; 1324 int result = 0, i, bytes = bits / 8; 1325 u8 *value = (u8 *)value64; 1326 1327 if ((address > 0xFF) || !value || !handler_context) 1328 return AE_BAD_PARAMETER; 1329 1330 if (function != ACPI_READ && function != ACPI_WRITE) 1331 return AE_BAD_PARAMETER; 1332 1333 if (ec->busy_polling || bits > 8) 1334 acpi_ec_burst_enable(ec); 1335 1336 for (i = 0; i < bytes; ++i, ++address, ++value) 1337 result = (function == ACPI_READ) ? 1338 acpi_ec_read(ec, address, value) : 1339 acpi_ec_write(ec, address, *value); 1340 1341 if (ec->busy_polling || bits > 8) 1342 acpi_ec_burst_disable(ec); 1343 1344 switch (result) { 1345 case -EINVAL: 1346 return AE_BAD_PARAMETER; 1347 case -ENODEV: 1348 return AE_NOT_FOUND; 1349 case -ETIME: 1350 return AE_TIME; 1351 default: 1352 return AE_OK; 1353 } 1354 } 1355 1356 /* -------------------------------------------------------------------------- 1357 * Driver Interface 1358 * -------------------------------------------------------------------------- */ 1359 1360 static acpi_status 1361 ec_parse_io_ports(struct acpi_resource *resource, void *context); 1362 1363 static void acpi_ec_free(struct acpi_ec *ec) 1364 { 1365 if (first_ec == ec) 1366 first_ec = NULL; 1367 if (boot_ec == ec) 1368 boot_ec = NULL; 1369 kfree(ec); 1370 } 1371 1372 static struct acpi_ec *acpi_ec_alloc(void) 1373 { 1374 struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL); 1375 1376 if (!ec) 1377 return NULL; 1378 mutex_init(&ec->mutex); 1379 init_waitqueue_head(&ec->wait); 1380 INIT_LIST_HEAD(&ec->list); 1381 spin_lock_init(&ec->lock); 1382 INIT_WORK(&ec->work, acpi_ec_event_handler); 1383 ec->timestamp = jiffies; 1384 ec->busy_polling = true; 1385 ec->polling_guard = 0; 1386 ec->gpe = -1; 1387 ec->irq = -1; 1388 return ec; 1389 } 1390 1391 static acpi_status 1392 acpi_ec_register_query_methods(acpi_handle handle, u32 level, 1393 void *context, void **return_value) 1394 { 1395 char node_name[5]; 1396 struct acpi_buffer buffer = { sizeof(node_name), node_name }; 1397 struct acpi_ec *ec = context; 1398 int value = 0; 1399 acpi_status status; 1400 1401 status = acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer); 1402 1403 if (ACPI_SUCCESS(status) && sscanf(node_name, "_Q%x", &value) == 1) 1404 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL); 1405 return AE_OK; 1406 } 1407 1408 static acpi_status 1409 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval) 1410 { 1411 acpi_status status; 1412 unsigned long long tmp = 0; 1413 struct acpi_ec *ec = context; 1414 1415 /* clear addr values, ec_parse_io_ports depend on it */ 1416 ec->command_addr = ec->data_addr = 0; 1417 1418 status = acpi_walk_resources(handle, METHOD_NAME__CRS, 1419 ec_parse_io_ports, ec); 1420 if (ACPI_FAILURE(status)) 1421 return status; 1422 if (ec->data_addr == 0 || ec->command_addr == 0) 1423 return AE_OK; 1424 1425 /* Get GPE bit assignment (EC events). */ 1426 /* TODO: Add support for _GPE returning a package */ 1427 status = acpi_evaluate_integer(handle, "_GPE", NULL, &tmp); 1428 if (ACPI_SUCCESS(status)) 1429 ec->gpe = tmp; 1430 /* 1431 * Errors are non-fatal, allowing for ACPI Reduced Hardware 1432 * platforms which use GpioInt instead of GPE. 1433 */ 1434 1435 /* Use the global lock for all EC transactions? */ 1436 tmp = 0; 1437 acpi_evaluate_integer(handle, "_GLK", NULL, &tmp); 1438 ec->global_lock = tmp; 1439 ec->handle = handle; 1440 return AE_CTRL_TERMINATE; 1441 } 1442 1443 static bool install_gpe_event_handler(struct acpi_ec *ec) 1444 { 1445 acpi_status status; 1446 1447 status = acpi_install_gpe_raw_handler(NULL, ec->gpe, 1448 ACPI_GPE_EDGE_TRIGGERED, 1449 &acpi_ec_gpe_handler, ec); 1450 if (ACPI_FAILURE(status)) 1451 return false; 1452 1453 if (test_bit(EC_FLAGS_STARTED, &ec->flags) && ec->reference_count >= 1) 1454 acpi_ec_enable_gpe(ec, true); 1455 1456 return true; 1457 } 1458 1459 static bool install_gpio_irq_event_handler(struct acpi_ec *ec) 1460 { 1461 return request_threaded_irq(ec->irq, NULL, acpi_ec_irq_handler, 1462 IRQF_SHARED | IRQF_ONESHOT, "ACPI EC", ec) >= 0; 1463 } 1464 1465 /** 1466 * ec_install_handlers - Install service callbacks and register query methods. 1467 * @ec: Target EC. 1468 * @device: ACPI device object corresponding to @ec. 1469 * @call_reg: If _REG should be called to notify OpRegion availability 1470 * 1471 * Install a handler for the EC address space type unless it has been installed 1472 * already. If @device is not NULL, also look for EC query methods in the 1473 * namespace and register them, and install an event (either GPE or GPIO IRQ) 1474 * handler for the EC, if possible. 1475 * 1476 * Return: 1477 * -ENODEV if the address space handler cannot be installed, which means 1478 * "unable to handle transactions", 1479 * -EPROBE_DEFER if GPIO IRQ acquisition needs to be deferred, 1480 * or 0 (success) otherwise. 1481 */ 1482 static int ec_install_handlers(struct acpi_ec *ec, struct acpi_device *device, 1483 bool call_reg) 1484 { 1485 acpi_status status; 1486 1487 acpi_ec_start(ec, false); 1488 1489 if (!test_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags)) { 1490 acpi_ec_enter_noirq(ec); 1491 status = acpi_install_address_space_handler_no_reg(ec->handle, 1492 ACPI_ADR_SPACE_EC, 1493 &acpi_ec_space_handler, 1494 NULL, ec); 1495 if (ACPI_FAILURE(status)) { 1496 acpi_ec_stop(ec, false); 1497 return -ENODEV; 1498 } 1499 set_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags); 1500 ec->address_space_handler_holder = ec->handle; 1501 } 1502 1503 if (call_reg && !test_bit(EC_FLAGS_EC_REG_CALLED, &ec->flags)) { 1504 acpi_execute_reg_methods(ec->handle, ACPI_ADR_SPACE_EC); 1505 set_bit(EC_FLAGS_EC_REG_CALLED, &ec->flags); 1506 } 1507 1508 if (!device) 1509 return 0; 1510 1511 if (ec->gpe < 0) { 1512 /* ACPI reduced hardware platforms use a GpioInt from _CRS. */ 1513 int irq = acpi_dev_gpio_irq_get(device, 0); 1514 /* 1515 * Bail out right away for deferred probing or complete the 1516 * initialization regardless of any other errors. 1517 */ 1518 if (irq == -EPROBE_DEFER) 1519 return -EPROBE_DEFER; 1520 else if (irq >= 0) 1521 ec->irq = irq; 1522 } 1523 1524 if (!test_bit(EC_FLAGS_QUERY_METHODS_INSTALLED, &ec->flags)) { 1525 /* Find and register all query methods */ 1526 acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1, 1527 acpi_ec_register_query_methods, 1528 NULL, ec, NULL); 1529 set_bit(EC_FLAGS_QUERY_METHODS_INSTALLED, &ec->flags); 1530 } 1531 if (!test_bit(EC_FLAGS_EVENT_HANDLER_INSTALLED, &ec->flags)) { 1532 bool ready = false; 1533 1534 if (ec->gpe >= 0) 1535 ready = install_gpe_event_handler(ec); 1536 else if (ec->irq >= 0) 1537 ready = install_gpio_irq_event_handler(ec); 1538 1539 if (ready) { 1540 set_bit(EC_FLAGS_EVENT_HANDLER_INSTALLED, &ec->flags); 1541 acpi_ec_leave_noirq(ec); 1542 } 1543 /* 1544 * Failures to install an event handler are not fatal, because 1545 * the EC can be polled for events. 1546 */ 1547 } 1548 /* EC is fully operational, allow queries */ 1549 acpi_ec_enable_event(ec); 1550 1551 return 0; 1552 } 1553 1554 static void ec_remove_handlers(struct acpi_ec *ec) 1555 { 1556 if (test_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags)) { 1557 if (ACPI_FAILURE(acpi_remove_address_space_handler( 1558 ec->address_space_handler_holder, 1559 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler))) 1560 pr_err("failed to remove space handler\n"); 1561 clear_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags); 1562 } 1563 1564 /* 1565 * Stops handling the EC transactions after removing the operation 1566 * region handler. This is required because _REG(DISCONNECT) 1567 * invoked during the removal can result in new EC transactions. 1568 * 1569 * Flushes the EC requests and thus disables the GPE before 1570 * removing the GPE handler. This is required by the current ACPICA 1571 * GPE core. ACPICA GPE core will automatically disable a GPE when 1572 * it is indicated but there is no way to handle it. So the drivers 1573 * must disable the GPEs prior to removing the GPE handlers. 1574 */ 1575 acpi_ec_stop(ec, false); 1576 1577 if (test_bit(EC_FLAGS_EVENT_HANDLER_INSTALLED, &ec->flags)) { 1578 if (ec->gpe >= 0 && 1579 ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe, 1580 &acpi_ec_gpe_handler))) 1581 pr_err("failed to remove gpe handler\n"); 1582 1583 if (ec->irq >= 0) 1584 free_irq(ec->irq, ec); 1585 1586 clear_bit(EC_FLAGS_EVENT_HANDLER_INSTALLED, &ec->flags); 1587 } 1588 if (test_bit(EC_FLAGS_QUERY_METHODS_INSTALLED, &ec->flags)) { 1589 acpi_ec_remove_query_handlers(ec, true, 0); 1590 clear_bit(EC_FLAGS_QUERY_METHODS_INSTALLED, &ec->flags); 1591 } 1592 } 1593 1594 static int acpi_ec_setup(struct acpi_ec *ec, struct acpi_device *device, bool call_reg) 1595 { 1596 int ret; 1597 1598 ret = ec_install_handlers(ec, device, call_reg); 1599 if (ret) 1600 return ret; 1601 1602 /* First EC capable of handling transactions */ 1603 if (!first_ec) 1604 first_ec = ec; 1605 1606 pr_info("EC_CMD/EC_SC=0x%lx, EC_DATA=0x%lx\n", ec->command_addr, 1607 ec->data_addr); 1608 1609 if (test_bit(EC_FLAGS_EVENT_HANDLER_INSTALLED, &ec->flags)) { 1610 if (ec->gpe >= 0) 1611 pr_info("GPE=0x%x\n", ec->gpe); 1612 else 1613 pr_info("IRQ=%d\n", ec->irq); 1614 } 1615 1616 return ret; 1617 } 1618 1619 static int acpi_ec_add(struct acpi_device *device) 1620 { 1621 struct acpi_ec *ec; 1622 int ret; 1623 1624 strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME); 1625 strcpy(acpi_device_class(device), ACPI_EC_CLASS); 1626 1627 if (boot_ec && (boot_ec->handle == device->handle || 1628 !strcmp(acpi_device_hid(device), ACPI_ECDT_HID))) { 1629 /* Fast path: this device corresponds to the boot EC. */ 1630 ec = boot_ec; 1631 } else { 1632 acpi_status status; 1633 1634 ec = acpi_ec_alloc(); 1635 if (!ec) 1636 return -ENOMEM; 1637 1638 status = ec_parse_device(device->handle, 0, ec, NULL); 1639 if (status != AE_CTRL_TERMINATE) { 1640 ret = -EINVAL; 1641 goto err; 1642 } 1643 1644 if (boot_ec && ec->command_addr == boot_ec->command_addr && 1645 ec->data_addr == boot_ec->data_addr) { 1646 /* 1647 * Trust PNP0C09 namespace location rather than ECDT ID. 1648 * But trust ECDT GPE rather than _GPE because of ASUS 1649 * quirks. So do not change boot_ec->gpe to ec->gpe, 1650 * except when the TRUST_DSDT_GPE quirk is set. 1651 */ 1652 boot_ec->handle = ec->handle; 1653 1654 if (EC_FLAGS_TRUST_DSDT_GPE) 1655 boot_ec->gpe = ec->gpe; 1656 1657 acpi_handle_debug(ec->handle, "duplicated.\n"); 1658 acpi_ec_free(ec); 1659 ec = boot_ec; 1660 } 1661 } 1662 1663 ret = acpi_ec_setup(ec, device, true); 1664 if (ret) 1665 goto err; 1666 1667 if (ec == boot_ec) 1668 acpi_handle_info(boot_ec->handle, 1669 "Boot %s EC initialization complete\n", 1670 boot_ec_is_ecdt ? "ECDT" : "DSDT"); 1671 1672 acpi_handle_info(ec->handle, 1673 "EC: Used to handle transactions and events\n"); 1674 1675 device->driver_data = ec; 1676 1677 ret = !!request_region(ec->data_addr, 1, "EC data"); 1678 WARN(!ret, "Could not request EC data io port 0x%lx", ec->data_addr); 1679 ret = !!request_region(ec->command_addr, 1, "EC cmd"); 1680 WARN(!ret, "Could not request EC cmd io port 0x%lx", ec->command_addr); 1681 1682 /* Reprobe devices depending on the EC */ 1683 acpi_dev_clear_dependencies(device); 1684 1685 acpi_handle_debug(ec->handle, "enumerated.\n"); 1686 return 0; 1687 1688 err: 1689 if (ec != boot_ec) 1690 acpi_ec_free(ec); 1691 1692 return ret; 1693 } 1694 1695 static void acpi_ec_remove(struct acpi_device *device) 1696 { 1697 struct acpi_ec *ec; 1698 1699 if (!device) 1700 return; 1701 1702 ec = acpi_driver_data(device); 1703 release_region(ec->data_addr, 1); 1704 release_region(ec->command_addr, 1); 1705 device->driver_data = NULL; 1706 if (ec != boot_ec) { 1707 ec_remove_handlers(ec); 1708 acpi_ec_free(ec); 1709 } 1710 } 1711 1712 static acpi_status 1713 ec_parse_io_ports(struct acpi_resource *resource, void *context) 1714 { 1715 struct acpi_ec *ec = context; 1716 1717 if (resource->type != ACPI_RESOURCE_TYPE_IO) 1718 return AE_OK; 1719 1720 /* 1721 * The first address region returned is the data port, and 1722 * the second address region returned is the status/command 1723 * port. 1724 */ 1725 if (ec->data_addr == 0) 1726 ec->data_addr = resource->data.io.minimum; 1727 else if (ec->command_addr == 0) 1728 ec->command_addr = resource->data.io.minimum; 1729 else 1730 return AE_CTRL_TERMINATE; 1731 1732 return AE_OK; 1733 } 1734 1735 static const struct acpi_device_id ec_device_ids[] = { 1736 {"PNP0C09", 0}, 1737 {ACPI_ECDT_HID, 0}, 1738 {"", 0}, 1739 }; 1740 1741 /* 1742 * This function is not Windows-compatible as Windows never enumerates the 1743 * namespace EC before the main ACPI device enumeration process. It is 1744 * retained for historical reason and will be deprecated in the future. 1745 */ 1746 void __init acpi_ec_dsdt_probe(void) 1747 { 1748 struct acpi_ec *ec; 1749 acpi_status status; 1750 int ret; 1751 1752 /* 1753 * If a platform has ECDT, there is no need to proceed as the 1754 * following probe is not a part of the ACPI device enumeration, 1755 * executing _STA is not safe, and thus this probe may risk of 1756 * picking up an invalid EC device. 1757 */ 1758 if (boot_ec) 1759 return; 1760 1761 ec = acpi_ec_alloc(); 1762 if (!ec) 1763 return; 1764 1765 /* 1766 * At this point, the namespace is initialized, so start to find 1767 * the namespace objects. 1768 */ 1769 status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device, ec, NULL); 1770 if (ACPI_FAILURE(status) || !ec->handle) { 1771 acpi_ec_free(ec); 1772 return; 1773 } 1774 1775 /* 1776 * When the DSDT EC is available, always re-configure boot EC to 1777 * have _REG evaluated. _REG can only be evaluated after the 1778 * namespace initialization. 1779 * At this point, the GPE is not fully initialized, so do not to 1780 * handle the events. 1781 */ 1782 ret = acpi_ec_setup(ec, NULL, true); 1783 if (ret) { 1784 acpi_ec_free(ec); 1785 return; 1786 } 1787 1788 boot_ec = ec; 1789 1790 acpi_handle_info(ec->handle, 1791 "Boot DSDT EC used to handle transactions\n"); 1792 } 1793 1794 /* 1795 * acpi_ec_ecdt_start - Finalize the boot ECDT EC initialization. 1796 * 1797 * First, look for an ACPI handle for the boot ECDT EC if acpi_ec_add() has not 1798 * found a matching object in the namespace. 1799 * 1800 * Next, in case the DSDT EC is not functioning, it is still necessary to 1801 * provide a functional ECDT EC to handle events, so add an extra device object 1802 * to represent it (see https://bugzilla.kernel.org/show_bug.cgi?id=115021). 1803 * 1804 * This is useful on platforms with valid ECDT and invalid DSDT EC settings, 1805 * like ASUS X550ZE (see https://bugzilla.kernel.org/show_bug.cgi?id=196847). 1806 */ 1807 static void __init acpi_ec_ecdt_start(void) 1808 { 1809 struct acpi_table_ecdt *ecdt_ptr; 1810 acpi_handle handle; 1811 acpi_status status; 1812 1813 /* Bail out if a matching EC has been found in the namespace. */ 1814 if (!boot_ec || boot_ec->handle != ACPI_ROOT_OBJECT) 1815 return; 1816 1817 /* Look up the object pointed to from the ECDT in the namespace. */ 1818 status = acpi_get_table(ACPI_SIG_ECDT, 1, 1819 (struct acpi_table_header **)&ecdt_ptr); 1820 if (ACPI_FAILURE(status)) 1821 return; 1822 1823 status = acpi_get_handle(NULL, ecdt_ptr->id, &handle); 1824 if (ACPI_SUCCESS(status)) { 1825 boot_ec->handle = handle; 1826 1827 /* Add a special ACPI device object to represent the boot EC. */ 1828 acpi_bus_register_early_device(ACPI_BUS_TYPE_ECDT_EC); 1829 } 1830 1831 acpi_put_table((struct acpi_table_header *)ecdt_ptr); 1832 } 1833 1834 /* 1835 * On some hardware it is necessary to clear events accumulated by the EC during 1836 * sleep. These ECs stop reporting GPEs until they are manually polled, if too 1837 * many events are accumulated. (e.g. Samsung Series 5/9 notebooks) 1838 * 1839 * https://bugzilla.kernel.org/show_bug.cgi?id=44161 1840 * 1841 * Ideally, the EC should also be instructed NOT to accumulate events during 1842 * sleep (which Windows seems to do somehow), but the interface to control this 1843 * behaviour is not known at this time. 1844 * 1845 * Models known to be affected are Samsung 530Uxx/535Uxx/540Uxx/550Pxx/900Xxx, 1846 * however it is very likely that other Samsung models are affected. 1847 * 1848 * On systems which don't accumulate _Q events during sleep, this extra check 1849 * should be harmless. 1850 */ 1851 static int ec_clear_on_resume(const struct dmi_system_id *id) 1852 { 1853 pr_debug("Detected system needing EC poll on resume.\n"); 1854 EC_FLAGS_CLEAR_ON_RESUME = 1; 1855 ec_event_clearing = ACPI_EC_EVT_TIMING_STATUS; 1856 return 0; 1857 } 1858 1859 /* 1860 * Some ECDTs contain wrong register addresses. 1861 * MSI MS-171F 1862 * https://bugzilla.kernel.org/show_bug.cgi?id=12461 1863 */ 1864 static int ec_correct_ecdt(const struct dmi_system_id *id) 1865 { 1866 pr_debug("Detected system needing ECDT address correction.\n"); 1867 EC_FLAGS_CORRECT_ECDT = 1; 1868 return 0; 1869 } 1870 1871 /* 1872 * Some ECDTs contain wrong GPE setting, but they share the same port addresses 1873 * with DSDT EC, don't duplicate the DSDT EC with ECDT EC in this case. 1874 * https://bugzilla.kernel.org/show_bug.cgi?id=209989 1875 */ 1876 static int ec_honor_dsdt_gpe(const struct dmi_system_id *id) 1877 { 1878 pr_debug("Detected system needing DSDT GPE setting.\n"); 1879 EC_FLAGS_TRUST_DSDT_GPE = 1; 1880 return 0; 1881 } 1882 1883 static const struct dmi_system_id ec_dmi_table[] __initconst = { 1884 { 1885 /* 1886 * MSI MS-171F 1887 * https://bugzilla.kernel.org/show_bug.cgi?id=12461 1888 */ 1889 .callback = ec_correct_ecdt, 1890 .matches = { 1891 DMI_MATCH(DMI_SYS_VENDOR, "Micro-Star"), 1892 DMI_MATCH(DMI_PRODUCT_NAME, "MS-171F"), 1893 }, 1894 }, 1895 { 1896 /* 1897 * HP Pavilion Gaming Laptop 15-cx0xxx 1898 * https://bugzilla.kernel.org/show_bug.cgi?id=209989 1899 */ 1900 .callback = ec_honor_dsdt_gpe, 1901 .matches = { 1902 DMI_MATCH(DMI_SYS_VENDOR, "HP"), 1903 DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion Gaming Laptop 15-cx0xxx"), 1904 }, 1905 }, 1906 { 1907 /* 1908 * HP Pavilion Gaming Laptop 15-cx0041ur 1909 */ 1910 .callback = ec_honor_dsdt_gpe, 1911 .matches = { 1912 DMI_MATCH(DMI_SYS_VENDOR, "HP"), 1913 DMI_MATCH(DMI_PRODUCT_NAME, "HP 15-cx0041ur"), 1914 }, 1915 }, 1916 { 1917 /* 1918 * HP Pavilion Gaming Laptop 15-dk1xxx 1919 * https://github.com/systemd/systemd/issues/28942 1920 */ 1921 .callback = ec_honor_dsdt_gpe, 1922 .matches = { 1923 DMI_MATCH(DMI_SYS_VENDOR, "HP"), 1924 DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion Gaming Laptop 15-dk1xxx"), 1925 }, 1926 }, 1927 { 1928 /* 1929 * HP 250 G7 Notebook PC 1930 */ 1931 .callback = ec_honor_dsdt_gpe, 1932 .matches = { 1933 DMI_MATCH(DMI_SYS_VENDOR, "HP"), 1934 DMI_MATCH(DMI_PRODUCT_NAME, "HP 250 G7 Notebook PC"), 1935 }, 1936 }, 1937 { 1938 /* 1939 * Samsung hardware 1940 * https://bugzilla.kernel.org/show_bug.cgi?id=44161 1941 */ 1942 .callback = ec_clear_on_resume, 1943 .matches = { 1944 DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."), 1945 }, 1946 }, 1947 {} 1948 }; 1949 1950 void __init acpi_ec_ecdt_probe(void) 1951 { 1952 struct acpi_table_ecdt *ecdt_ptr; 1953 struct acpi_ec *ec; 1954 acpi_status status; 1955 int ret; 1956 1957 /* Generate a boot ec context. */ 1958 dmi_check_system(ec_dmi_table); 1959 status = acpi_get_table(ACPI_SIG_ECDT, 1, 1960 (struct acpi_table_header **)&ecdt_ptr); 1961 if (ACPI_FAILURE(status)) 1962 return; 1963 1964 if (!ecdt_ptr->control.address || !ecdt_ptr->data.address) { 1965 /* 1966 * Asus X50GL: 1967 * https://bugzilla.kernel.org/show_bug.cgi?id=11880 1968 */ 1969 goto out; 1970 } 1971 1972 ec = acpi_ec_alloc(); 1973 if (!ec) 1974 goto out; 1975 1976 if (EC_FLAGS_CORRECT_ECDT) { 1977 ec->command_addr = ecdt_ptr->data.address; 1978 ec->data_addr = ecdt_ptr->control.address; 1979 } else { 1980 ec->command_addr = ecdt_ptr->control.address; 1981 ec->data_addr = ecdt_ptr->data.address; 1982 } 1983 1984 /* 1985 * Ignore the GPE value on Reduced Hardware platforms. 1986 * Some products have this set to an erroneous value. 1987 */ 1988 if (!acpi_gbl_reduced_hardware) 1989 ec->gpe = ecdt_ptr->gpe; 1990 1991 ec->handle = ACPI_ROOT_OBJECT; 1992 1993 /* 1994 * At this point, the namespace is not initialized, so do not find 1995 * the namespace objects, or handle the events. 1996 */ 1997 ret = acpi_ec_setup(ec, NULL, false); 1998 if (ret) { 1999 acpi_ec_free(ec); 2000 goto out; 2001 } 2002 2003 boot_ec = ec; 2004 boot_ec_is_ecdt = true; 2005 2006 pr_info("Boot ECDT EC used to handle transactions\n"); 2007 2008 out: 2009 acpi_put_table((struct acpi_table_header *)ecdt_ptr); 2010 } 2011 2012 #ifdef CONFIG_PM_SLEEP 2013 static int acpi_ec_suspend(struct device *dev) 2014 { 2015 struct acpi_ec *ec = 2016 acpi_driver_data(to_acpi_device(dev)); 2017 2018 if (!pm_suspend_no_platform() && ec_freeze_events) 2019 acpi_ec_disable_event(ec); 2020 return 0; 2021 } 2022 2023 static int acpi_ec_suspend_noirq(struct device *dev) 2024 { 2025 struct acpi_ec *ec = acpi_driver_data(to_acpi_device(dev)); 2026 2027 /* 2028 * The SCI handler doesn't run at this point, so the GPE can be 2029 * masked at the low level without side effects. 2030 */ 2031 if (ec_no_wakeup && test_bit(EC_FLAGS_STARTED, &ec->flags) && 2032 ec->gpe >= 0 && ec->reference_count >= 1) 2033 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_DISABLE); 2034 2035 acpi_ec_enter_noirq(ec); 2036 2037 return 0; 2038 } 2039 2040 static int acpi_ec_resume_noirq(struct device *dev) 2041 { 2042 struct acpi_ec *ec = acpi_driver_data(to_acpi_device(dev)); 2043 2044 acpi_ec_leave_noirq(ec); 2045 2046 if (ec_no_wakeup && test_bit(EC_FLAGS_STARTED, &ec->flags) && 2047 ec->gpe >= 0 && ec->reference_count >= 1) 2048 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_ENABLE); 2049 2050 return 0; 2051 } 2052 2053 static int acpi_ec_resume(struct device *dev) 2054 { 2055 struct acpi_ec *ec = 2056 acpi_driver_data(to_acpi_device(dev)); 2057 2058 acpi_ec_enable_event(ec); 2059 return 0; 2060 } 2061 2062 void acpi_ec_mark_gpe_for_wake(void) 2063 { 2064 if (first_ec && !ec_no_wakeup) 2065 acpi_mark_gpe_for_wake(NULL, first_ec->gpe); 2066 } 2067 EXPORT_SYMBOL_GPL(acpi_ec_mark_gpe_for_wake); 2068 2069 void acpi_ec_set_gpe_wake_mask(u8 action) 2070 { 2071 if (pm_suspend_no_platform() && first_ec && !ec_no_wakeup) 2072 acpi_set_gpe_wake_mask(NULL, first_ec->gpe, action); 2073 } 2074 2075 static bool acpi_ec_work_in_progress(struct acpi_ec *ec) 2076 { 2077 return ec->events_in_progress + ec->queries_in_progress > 0; 2078 } 2079 2080 bool acpi_ec_dispatch_gpe(void) 2081 { 2082 bool work_in_progress = false; 2083 2084 if (!first_ec) 2085 return acpi_any_gpe_status_set(U32_MAX); 2086 2087 /* 2088 * Report wakeup if the status bit is set for any enabled GPE other 2089 * than the EC one. 2090 */ 2091 if (acpi_any_gpe_status_set(first_ec->gpe)) 2092 return true; 2093 2094 /* 2095 * Cancel the SCI wakeup and process all pending events in case there 2096 * are any wakeup ones in there. 2097 * 2098 * Note that if any non-EC GPEs are active at this point, the SCI will 2099 * retrigger after the rearming in acpi_s2idle_wake(), so no events 2100 * should be missed by canceling the wakeup here. 2101 */ 2102 pm_system_cancel_wakeup(); 2103 2104 /* 2105 * Dispatch the EC GPE in-band, but do not report wakeup in any case 2106 * to allow the caller to process events properly after that. 2107 */ 2108 spin_lock_irq(&first_ec->lock); 2109 2110 if (acpi_ec_gpe_status_set(first_ec)) { 2111 pm_pr_dbg("ACPI EC GPE status set\n"); 2112 2113 clear_gpe_and_advance_transaction(first_ec, false); 2114 work_in_progress = acpi_ec_work_in_progress(first_ec); 2115 } 2116 2117 spin_unlock_irq(&first_ec->lock); 2118 2119 if (!work_in_progress) 2120 return false; 2121 2122 pm_pr_dbg("ACPI EC GPE dispatched\n"); 2123 2124 /* Drain EC work. */ 2125 do { 2126 acpi_ec_flush_work(); 2127 2128 pm_pr_dbg("ACPI EC work flushed\n"); 2129 2130 spin_lock_irq(&first_ec->lock); 2131 2132 work_in_progress = acpi_ec_work_in_progress(first_ec); 2133 2134 spin_unlock_irq(&first_ec->lock); 2135 } while (work_in_progress && !pm_wakeup_pending()); 2136 2137 return false; 2138 } 2139 #endif /* CONFIG_PM_SLEEP */ 2140 2141 static const struct dev_pm_ops acpi_ec_pm = { 2142 SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(acpi_ec_suspend_noirq, acpi_ec_resume_noirq) 2143 SET_SYSTEM_SLEEP_PM_OPS(acpi_ec_suspend, acpi_ec_resume) 2144 }; 2145 2146 static int param_set_event_clearing(const char *val, 2147 const struct kernel_param *kp) 2148 { 2149 int result = 0; 2150 2151 if (!strncmp(val, "status", sizeof("status") - 1)) { 2152 ec_event_clearing = ACPI_EC_EVT_TIMING_STATUS; 2153 pr_info("Assuming SCI_EVT clearing on EC_SC accesses\n"); 2154 } else if (!strncmp(val, "query", sizeof("query") - 1)) { 2155 ec_event_clearing = ACPI_EC_EVT_TIMING_QUERY; 2156 pr_info("Assuming SCI_EVT clearing on QR_EC writes\n"); 2157 } else if (!strncmp(val, "event", sizeof("event") - 1)) { 2158 ec_event_clearing = ACPI_EC_EVT_TIMING_EVENT; 2159 pr_info("Assuming SCI_EVT clearing on event reads\n"); 2160 } else 2161 result = -EINVAL; 2162 return result; 2163 } 2164 2165 static int param_get_event_clearing(char *buffer, 2166 const struct kernel_param *kp) 2167 { 2168 switch (ec_event_clearing) { 2169 case ACPI_EC_EVT_TIMING_STATUS: 2170 return sprintf(buffer, "status\n"); 2171 case ACPI_EC_EVT_TIMING_QUERY: 2172 return sprintf(buffer, "query\n"); 2173 case ACPI_EC_EVT_TIMING_EVENT: 2174 return sprintf(buffer, "event\n"); 2175 default: 2176 return sprintf(buffer, "invalid\n"); 2177 } 2178 return 0; 2179 } 2180 2181 module_param_call(ec_event_clearing, param_set_event_clearing, param_get_event_clearing, 2182 NULL, 0644); 2183 MODULE_PARM_DESC(ec_event_clearing, "Assumed SCI_EVT clearing timing"); 2184 2185 static struct acpi_driver acpi_ec_driver = { 2186 .name = "ec", 2187 .class = ACPI_EC_CLASS, 2188 .ids = ec_device_ids, 2189 .ops = { 2190 .add = acpi_ec_add, 2191 .remove = acpi_ec_remove, 2192 }, 2193 .drv.pm = &acpi_ec_pm, 2194 }; 2195 2196 static void acpi_ec_destroy_workqueues(void) 2197 { 2198 if (ec_wq) { 2199 destroy_workqueue(ec_wq); 2200 ec_wq = NULL; 2201 } 2202 if (ec_query_wq) { 2203 destroy_workqueue(ec_query_wq); 2204 ec_query_wq = NULL; 2205 } 2206 } 2207 2208 static int acpi_ec_init_workqueues(void) 2209 { 2210 if (!ec_wq) 2211 ec_wq = alloc_ordered_workqueue("kec", 0); 2212 2213 if (!ec_query_wq) 2214 ec_query_wq = alloc_workqueue("kec_query", 0, ec_max_queries); 2215 2216 if (!ec_wq || !ec_query_wq) { 2217 acpi_ec_destroy_workqueues(); 2218 return -ENODEV; 2219 } 2220 return 0; 2221 } 2222 2223 static const struct dmi_system_id acpi_ec_no_wakeup[] = { 2224 { 2225 .matches = { 2226 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"), 2227 DMI_MATCH(DMI_PRODUCT_FAMILY, "Thinkpad X1 Carbon 6th"), 2228 }, 2229 }, 2230 { 2231 .matches = { 2232 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"), 2233 DMI_MATCH(DMI_PRODUCT_FAMILY, "ThinkPad X1 Yoga 3rd"), 2234 }, 2235 }, 2236 { 2237 .matches = { 2238 DMI_MATCH(DMI_SYS_VENDOR, "HP"), 2239 DMI_MATCH(DMI_PRODUCT_FAMILY, "103C_5336AN HP ZHAN 66 Pro"), 2240 }, 2241 }, 2242 { }, 2243 }; 2244 2245 void __init acpi_ec_init(void) 2246 { 2247 int result; 2248 2249 result = acpi_ec_init_workqueues(); 2250 if (result) 2251 return; 2252 2253 /* 2254 * Disable EC wakeup on following systems to prevent periodic 2255 * wakeup from EC GPE. 2256 */ 2257 if (dmi_check_system(acpi_ec_no_wakeup)) { 2258 ec_no_wakeup = true; 2259 pr_debug("Disabling EC wakeup on suspend-to-idle\n"); 2260 } 2261 2262 /* Driver must be registered after acpi_ec_init_workqueues(). */ 2263 acpi_bus_register_driver(&acpi_ec_driver); 2264 2265 acpi_ec_ecdt_start(); 2266 } 2267 2268 /* EC driver currently not unloadable */ 2269 #if 0 2270 static void __exit acpi_ec_exit(void) 2271 { 2272 2273 acpi_bus_unregister_driver(&acpi_ec_driver); 2274 acpi_ec_destroy_workqueues(); 2275 } 2276 #endif /* 0 */ 2277