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/platform_device.h> 27 #include <linux/printk.h> 28 #include <linux/spinlock.h> 29 #include <linux/slab.h> 30 #include <linux/string.h> 31 #include <linux/suspend.h> 32 #include <linux/acpi.h> 33 #include <linux/dmi.h> 34 #include <asm/io.h> 35 36 #include "internal.h" 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 if (t->rdata) 787 memset(t->rdata, 0, t->rlen); 788 789 /* start transaction */ 790 spin_lock_irqsave(&ec->lock, tmp); 791 /* Enable GPE for command processing (IBF=0/OBF=1) */ 792 if (!acpi_ec_submit_flushable_request(ec)) { 793 ret = -EINVAL; 794 goto unlock; 795 } 796 ec_dbg_ref(ec, "Increase command"); 797 /* following two actions should be kept atomic */ 798 ec->curr = t; 799 ec_dbg_req("Command(%s) started", acpi_ec_cmd_string(t->command)); 800 start_transaction(ec); 801 spin_unlock_irqrestore(&ec->lock, tmp); 802 803 ret = ec_poll(ec); 804 805 spin_lock_irqsave(&ec->lock, tmp); 806 if (t->irq_count == ec_storm_threshold) 807 acpi_ec_unmask_events(ec); 808 ec_dbg_req("Command(%s) stopped", acpi_ec_cmd_string(t->command)); 809 ec->curr = NULL; 810 /* Disable GPE for command processing (IBF=0/OBF=1) */ 811 acpi_ec_complete_request(ec); 812 ec_dbg_ref(ec, "Decrease command"); 813 unlock: 814 spin_unlock_irqrestore(&ec->lock, tmp); 815 return ret; 816 } 817 818 static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t) 819 { 820 int status; 821 u32 glk; 822 823 if (!ec || (!t) || (t->wlen && !t->wdata) || (t->rlen && !t->rdata)) 824 return -EINVAL; 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_unlocked(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_unlocked(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_read_unlocked(struct acpi_ec *ec, u8 address, u8 *data) 878 { 879 int result; 880 u8 d; 881 struct transaction t = {.command = ACPI_EC_COMMAND_READ, 882 .wdata = &address, .rdata = &d, 883 .wlen = 1, .rlen = 1}; 884 885 result = acpi_ec_transaction_unlocked(ec, &t); 886 *data = d; 887 return result; 888 } 889 890 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data) 891 { 892 u8 wdata[2] = { address, data }; 893 struct transaction t = {.command = ACPI_EC_COMMAND_WRITE, 894 .wdata = wdata, .rdata = NULL, 895 .wlen = 2, .rlen = 0}; 896 897 return acpi_ec_transaction(ec, &t); 898 } 899 900 static int acpi_ec_write_unlocked(struct acpi_ec *ec, u8 address, u8 data) 901 { 902 u8 wdata[2] = { address, data }; 903 struct transaction t = {.command = ACPI_EC_COMMAND_WRITE, 904 .wdata = wdata, .rdata = NULL, 905 .wlen = 2, .rlen = 0}; 906 907 return acpi_ec_transaction_unlocked(ec, &t); 908 } 909 910 int ec_read(u8 addr, u8 *val) 911 { 912 int err; 913 u8 temp_data; 914 915 if (!first_ec) 916 return -ENODEV; 917 918 err = acpi_ec_read(first_ec, addr, &temp_data); 919 920 if (!err) { 921 *val = temp_data; 922 return 0; 923 } 924 return err; 925 } 926 EXPORT_SYMBOL(ec_read); 927 928 int ec_write(u8 addr, u8 val) 929 { 930 if (!first_ec) 931 return -ENODEV; 932 933 return acpi_ec_write(first_ec, addr, val); 934 } 935 EXPORT_SYMBOL(ec_write); 936 937 int ec_transaction(u8 command, 938 const u8 *wdata, unsigned wdata_len, 939 u8 *rdata, unsigned rdata_len) 940 { 941 struct transaction t = {.command = command, 942 .wdata = wdata, .rdata = rdata, 943 .wlen = wdata_len, .rlen = rdata_len}; 944 945 if (!first_ec) 946 return -ENODEV; 947 948 return acpi_ec_transaction(first_ec, &t); 949 } 950 EXPORT_SYMBOL(ec_transaction); 951 952 /* Get the handle to the EC device */ 953 acpi_handle ec_get_handle(void) 954 { 955 if (!first_ec) 956 return NULL; 957 return first_ec->handle; 958 } 959 EXPORT_SYMBOL(ec_get_handle); 960 961 static void acpi_ec_start(struct acpi_ec *ec, bool resuming) 962 { 963 unsigned long flags; 964 965 spin_lock_irqsave(&ec->lock, flags); 966 if (!test_and_set_bit(EC_FLAGS_STARTED, &ec->flags)) { 967 ec_dbg_drv("Starting EC"); 968 /* Enable GPE for event processing (SCI_EVT=1) */ 969 if (!resuming) { 970 acpi_ec_submit_request(ec); 971 ec_dbg_ref(ec, "Increase driver"); 972 } 973 ec_log_drv("EC started"); 974 } 975 spin_unlock_irqrestore(&ec->lock, flags); 976 } 977 978 static bool acpi_ec_stopped(struct acpi_ec *ec) 979 { 980 unsigned long flags; 981 bool flushed; 982 983 spin_lock_irqsave(&ec->lock, flags); 984 flushed = acpi_ec_flushed(ec); 985 spin_unlock_irqrestore(&ec->lock, flags); 986 return flushed; 987 } 988 989 static void acpi_ec_stop(struct acpi_ec *ec, bool suspending) 990 { 991 unsigned long flags; 992 993 spin_lock_irqsave(&ec->lock, flags); 994 if (acpi_ec_started(ec)) { 995 ec_dbg_drv("Stopping EC"); 996 set_bit(EC_FLAGS_STOPPED, &ec->flags); 997 spin_unlock_irqrestore(&ec->lock, flags); 998 wait_event(ec->wait, acpi_ec_stopped(ec)); 999 spin_lock_irqsave(&ec->lock, flags); 1000 /* Disable GPE for event processing (SCI_EVT=1) */ 1001 if (!suspending) { 1002 acpi_ec_complete_request(ec); 1003 ec_dbg_ref(ec, "Decrease driver"); 1004 } else if (!ec_freeze_events) 1005 __acpi_ec_disable_event(ec); 1006 clear_bit(EC_FLAGS_STARTED, &ec->flags); 1007 clear_bit(EC_FLAGS_STOPPED, &ec->flags); 1008 ec_log_drv("EC stopped"); 1009 } 1010 spin_unlock_irqrestore(&ec->lock, flags); 1011 } 1012 1013 static void acpi_ec_enter_noirq(struct acpi_ec *ec) 1014 { 1015 unsigned long flags; 1016 1017 spin_lock_irqsave(&ec->lock, flags); 1018 ec->busy_polling = true; 1019 ec->polling_guard = 0; 1020 ec_log_drv("interrupt blocked"); 1021 spin_unlock_irqrestore(&ec->lock, flags); 1022 } 1023 1024 static void acpi_ec_leave_noirq(struct acpi_ec *ec) 1025 { 1026 unsigned long flags; 1027 1028 spin_lock_irqsave(&ec->lock, flags); 1029 ec->busy_polling = ec_busy_polling; 1030 ec->polling_guard = ec_polling_guard; 1031 ec_log_drv("interrupt unblocked"); 1032 spin_unlock_irqrestore(&ec->lock, flags); 1033 } 1034 1035 void acpi_ec_block_transactions(void) 1036 { 1037 struct acpi_ec *ec = first_ec; 1038 1039 if (!ec) 1040 return; 1041 1042 mutex_lock(&ec->mutex); 1043 /* Prevent transactions from being carried out */ 1044 acpi_ec_stop(ec, true); 1045 mutex_unlock(&ec->mutex); 1046 } 1047 1048 void acpi_ec_unblock_transactions(void) 1049 { 1050 /* 1051 * Allow transactions to happen again (this function is called from 1052 * atomic context during wakeup, so we don't need to acquire the mutex). 1053 */ 1054 if (first_ec) 1055 acpi_ec_start(first_ec, true); 1056 } 1057 1058 /* -------------------------------------------------------------------------- 1059 Event Management 1060 -------------------------------------------------------------------------- */ 1061 static struct acpi_ec_query_handler * 1062 acpi_ec_get_query_handler_by_value(struct acpi_ec *ec, u8 value) 1063 { 1064 struct acpi_ec_query_handler *handler; 1065 1066 mutex_lock(&ec->mutex); 1067 list_for_each_entry(handler, &ec->list, node) { 1068 if (value == handler->query_bit) { 1069 kref_get(&handler->kref); 1070 mutex_unlock(&ec->mutex); 1071 return handler; 1072 } 1073 } 1074 mutex_unlock(&ec->mutex); 1075 return NULL; 1076 } 1077 1078 static void acpi_ec_query_handler_release(struct kref *kref) 1079 { 1080 struct acpi_ec_query_handler *handler = 1081 container_of(kref, struct acpi_ec_query_handler, kref); 1082 1083 kfree(handler); 1084 } 1085 1086 static void acpi_ec_put_query_handler(struct acpi_ec_query_handler *handler) 1087 { 1088 kref_put(&handler->kref, acpi_ec_query_handler_release); 1089 } 1090 1091 int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit, 1092 acpi_handle handle, acpi_ec_query_func func, 1093 void *data) 1094 { 1095 struct acpi_ec_query_handler *handler; 1096 1097 if (!handle && !func) 1098 return -EINVAL; 1099 1100 handler = kzalloc_obj(*handler); 1101 if (!handler) 1102 return -ENOMEM; 1103 1104 handler->query_bit = query_bit; 1105 handler->handle = handle; 1106 handler->func = func; 1107 handler->data = data; 1108 mutex_lock(&ec->mutex); 1109 kref_init(&handler->kref); 1110 list_add(&handler->node, &ec->list); 1111 mutex_unlock(&ec->mutex); 1112 1113 return 0; 1114 } 1115 EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler); 1116 1117 static void acpi_ec_remove_query_handlers(struct acpi_ec *ec, 1118 bool remove_all, u8 query_bit) 1119 { 1120 struct acpi_ec_query_handler *handler, *tmp; 1121 LIST_HEAD(free_list); 1122 1123 mutex_lock(&ec->mutex); 1124 list_for_each_entry_safe(handler, tmp, &ec->list, node) { 1125 /* 1126 * When remove_all is false, only remove custom query handlers 1127 * which have handler->func set. This is done to preserve query 1128 * handlers discovered thru ACPI, as they should continue handling 1129 * EC queries. 1130 */ 1131 if (remove_all || (handler->func && handler->query_bit == query_bit)) { 1132 list_del_init(&handler->node); 1133 list_add(&handler->node, &free_list); 1134 1135 } 1136 } 1137 mutex_unlock(&ec->mutex); 1138 list_for_each_entry_safe(handler, tmp, &free_list, node) 1139 acpi_ec_put_query_handler(handler); 1140 } 1141 1142 void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit) 1143 { 1144 acpi_ec_remove_query_handlers(ec, false, query_bit); 1145 flush_workqueue(ec_query_wq); 1146 } 1147 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler); 1148 1149 static void acpi_ec_event_processor(struct work_struct *work) 1150 { 1151 struct acpi_ec_query *q = container_of(work, struct acpi_ec_query, work); 1152 struct acpi_ec_query_handler *handler = q->handler; 1153 struct acpi_ec *ec = q->ec; 1154 1155 ec_dbg_evt("Query(0x%02x) started", handler->query_bit); 1156 1157 if (handler->func) 1158 handler->func(handler->data); 1159 else if (handler->handle) 1160 acpi_evaluate_object(handler->handle, NULL, NULL, NULL); 1161 1162 ec_dbg_evt("Query(0x%02x) stopped", handler->query_bit); 1163 1164 spin_lock_irq(&ec->lock); 1165 ec->queries_in_progress--; 1166 spin_unlock_irq(&ec->lock); 1167 1168 acpi_ec_put_query_handler(handler); 1169 kfree(q); 1170 } 1171 1172 static struct acpi_ec_query *acpi_ec_create_query(struct acpi_ec *ec, u8 *pval) 1173 { 1174 struct acpi_ec_query *q; 1175 struct transaction *t; 1176 1177 q = kzalloc_obj(struct acpi_ec_query); 1178 if (!q) 1179 return NULL; 1180 1181 INIT_WORK(&q->work, acpi_ec_event_processor); 1182 t = &q->transaction; 1183 t->command = ACPI_EC_COMMAND_QUERY; 1184 t->rdata = pval; 1185 t->rlen = 1; 1186 q->ec = ec; 1187 return q; 1188 } 1189 1190 static int acpi_ec_submit_query(struct acpi_ec *ec) 1191 { 1192 struct acpi_ec_query *q; 1193 u8 value = 0; 1194 int result; 1195 1196 q = acpi_ec_create_query(ec, &value); 1197 if (!q) 1198 return -ENOMEM; 1199 1200 /* 1201 * Query the EC to find out which _Qxx method we need to evaluate. 1202 * Note that successful completion of the query causes the ACPI_EC_SCI 1203 * bit to be cleared (and thus clearing the interrupt source). 1204 */ 1205 result = acpi_ec_transaction(ec, &q->transaction); 1206 if (result) 1207 goto err_exit; 1208 1209 if (!value) { 1210 result = -ENODATA; 1211 goto err_exit; 1212 } 1213 1214 q->handler = acpi_ec_get_query_handler_by_value(ec, value); 1215 if (!q->handler) { 1216 result = -ENODATA; 1217 goto err_exit; 1218 } 1219 1220 /* 1221 * It is reported that _Qxx are evaluated in a parallel way on Windows: 1222 * https://bugzilla.kernel.org/show_bug.cgi?id=94411 1223 * 1224 * Put this log entry before queue_work() to make it appear in the log 1225 * before any other messages emitted during workqueue handling. 1226 */ 1227 ec_dbg_evt("Query(0x%02x) scheduled", value); 1228 1229 spin_lock_irq(&ec->lock); 1230 1231 ec->queries_in_progress++; 1232 queue_work(ec_query_wq, &q->work); 1233 1234 spin_unlock_irq(&ec->lock); 1235 1236 return 0; 1237 1238 err_exit: 1239 kfree(q); 1240 1241 return result; 1242 } 1243 1244 static void acpi_ec_event_handler(struct work_struct *work) 1245 { 1246 struct acpi_ec *ec = container_of(work, struct acpi_ec, work); 1247 1248 ec_dbg_evt("Event started"); 1249 1250 spin_lock_irq(&ec->lock); 1251 1252 while (ec->events_to_process) { 1253 spin_unlock_irq(&ec->lock); 1254 1255 acpi_ec_submit_query(ec); 1256 1257 spin_lock_irq(&ec->lock); 1258 1259 ec->events_to_process--; 1260 } 1261 1262 /* 1263 * Before exit, make sure that the it will be possible to queue up the 1264 * event handling work again regardless of whether or not the query 1265 * queued up above is processed successfully. 1266 */ 1267 if (ec_event_clearing == ACPI_EC_EVT_TIMING_EVENT) { 1268 bool guard_timeout; 1269 1270 acpi_ec_complete_event(ec); 1271 1272 ec_dbg_evt("Event stopped"); 1273 1274 spin_unlock_irq(&ec->lock); 1275 1276 guard_timeout = !!ec_guard(ec); 1277 1278 spin_lock_irq(&ec->lock); 1279 1280 /* Take care of SCI_EVT unless someone else is doing that. */ 1281 if (guard_timeout && !ec->curr) 1282 advance_transaction(ec, false); 1283 } else { 1284 acpi_ec_close_event(ec); 1285 1286 ec_dbg_evt("Event stopped"); 1287 } 1288 1289 ec->events_in_progress--; 1290 1291 spin_unlock_irq(&ec->lock); 1292 } 1293 1294 static void clear_gpe_and_advance_transaction(struct acpi_ec *ec, bool interrupt) 1295 { 1296 /* 1297 * Clear GPE_STS upfront to allow subsequent hardware GPE_STS 0->1 1298 * changes to always trigger a GPE interrupt. 1299 * 1300 * GPE STS is a W1C register, which means: 1301 * 1302 * 1. Software can clear it without worrying about clearing the other 1303 * GPEs' STS bits when the hardware sets them in parallel. 1304 * 1305 * 2. As long as software can ensure only clearing it when it is set, 1306 * hardware won't set it in parallel. 1307 */ 1308 if (ec->gpe >= 0 && acpi_ec_gpe_status_set(ec)) 1309 acpi_clear_gpe(NULL, ec->gpe); 1310 1311 advance_transaction(ec, true); 1312 } 1313 1314 static void acpi_ec_handle_interrupt(struct acpi_ec *ec) 1315 { 1316 unsigned long flags; 1317 1318 spin_lock_irqsave(&ec->lock, flags); 1319 1320 clear_gpe_and_advance_transaction(ec, true); 1321 1322 spin_unlock_irqrestore(&ec->lock, flags); 1323 } 1324 1325 static u32 acpi_ec_gpe_handler(acpi_handle gpe_device, 1326 u32 gpe_number, void *data) 1327 { 1328 acpi_ec_handle_interrupt(data); 1329 return ACPI_INTERRUPT_HANDLED; 1330 } 1331 1332 static irqreturn_t acpi_ec_irq_handler(int irq, void *data) 1333 { 1334 acpi_ec_handle_interrupt(data); 1335 return IRQ_HANDLED; 1336 } 1337 1338 /* -------------------------------------------------------------------------- 1339 * Address Space Management 1340 * -------------------------------------------------------------------------- */ 1341 1342 static acpi_status 1343 acpi_ec_space_handler(u32 function, acpi_physical_address address, 1344 u32 bits, u64 *value64, 1345 void *handler_context, void *region_context) 1346 { 1347 struct acpi_ec *ec = handler_context; 1348 int result = 0, i, bytes = bits / 8; 1349 u8 *value = (u8 *)value64; 1350 u32 glk; 1351 1352 if ((address > 0xFF) || !value || !handler_context) 1353 return AE_BAD_PARAMETER; 1354 1355 if (function != ACPI_READ && function != ACPI_WRITE) 1356 return AE_BAD_PARAMETER; 1357 1358 mutex_lock(&ec->mutex); 1359 1360 if (ec->global_lock) { 1361 acpi_status status; 1362 1363 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk); 1364 if (ACPI_FAILURE(status)) { 1365 result = -ENODEV; 1366 goto unlock; 1367 } 1368 } 1369 1370 if (ec->busy_polling || bits > 8) 1371 acpi_ec_burst_enable(ec); 1372 1373 for (i = 0; i < bytes; ++i, ++address, ++value) { 1374 result = (function == ACPI_READ) ? 1375 acpi_ec_read_unlocked(ec, address, value) : 1376 acpi_ec_write_unlocked(ec, address, *value); 1377 if (result < 0) 1378 break; 1379 } 1380 1381 if (ec->busy_polling || bits > 8) 1382 acpi_ec_burst_disable(ec); 1383 1384 if (ec->global_lock) 1385 acpi_release_global_lock(glk); 1386 1387 unlock: 1388 mutex_unlock(&ec->mutex); 1389 1390 switch (result) { 1391 case -EINVAL: 1392 return AE_BAD_PARAMETER; 1393 case -ENODEV: 1394 return AE_NOT_FOUND; 1395 case -ETIME: 1396 return AE_TIME; 1397 case 0: 1398 return AE_OK; 1399 default: 1400 return AE_ERROR; 1401 } 1402 } 1403 1404 /* -------------------------------------------------------------------------- 1405 * Driver Interface 1406 * -------------------------------------------------------------------------- */ 1407 1408 static acpi_status 1409 ec_parse_io_ports(struct acpi_resource *resource, void *context); 1410 1411 static void acpi_ec_free(struct acpi_ec *ec) 1412 { 1413 if (first_ec == ec) 1414 first_ec = NULL; 1415 if (boot_ec == ec) 1416 boot_ec = NULL; 1417 kfree(ec); 1418 } 1419 1420 static struct acpi_ec *acpi_ec_alloc(void) 1421 { 1422 struct acpi_ec *ec = kzalloc_obj(struct acpi_ec); 1423 1424 if (!ec) 1425 return NULL; 1426 mutex_init(&ec->mutex); 1427 init_waitqueue_head(&ec->wait); 1428 INIT_LIST_HEAD(&ec->list); 1429 spin_lock_init(&ec->lock); 1430 INIT_WORK(&ec->work, acpi_ec_event_handler); 1431 ec->timestamp = jiffies; 1432 ec->busy_polling = true; 1433 ec->polling_guard = 0; 1434 ec->gpe = -1; 1435 ec->irq = -1; 1436 return ec; 1437 } 1438 1439 static acpi_status 1440 acpi_ec_register_query_methods(acpi_handle handle, u32 level, 1441 void *context, void **return_value) 1442 { 1443 char node_name[5]; 1444 struct acpi_buffer buffer = { sizeof(node_name), node_name }; 1445 struct acpi_ec *ec = context; 1446 int value = 0; 1447 acpi_status status; 1448 1449 status = acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer); 1450 1451 if (ACPI_SUCCESS(status) && sscanf(node_name, "_Q%x", &value) == 1) 1452 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL); 1453 return AE_OK; 1454 } 1455 1456 static acpi_status 1457 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval) 1458 { 1459 acpi_status status; 1460 unsigned long long tmp = 0; 1461 struct acpi_ec *ec = context; 1462 1463 /* clear addr values, ec_parse_io_ports depend on it */ 1464 ec->command_addr = ec->data_addr = 0; 1465 1466 status = acpi_walk_resources(handle, METHOD_NAME__CRS, 1467 ec_parse_io_ports, ec); 1468 if (ACPI_FAILURE(status)) 1469 return status; 1470 if (ec->data_addr == 0 || ec->command_addr == 0) 1471 return AE_OK; 1472 1473 /* Get GPE bit assignment (EC events). */ 1474 /* TODO: Add support for _GPE returning a package */ 1475 status = acpi_evaluate_integer(handle, "_GPE", NULL, &tmp); 1476 if (ACPI_SUCCESS(status)) 1477 ec->gpe = tmp; 1478 /* 1479 * Errors are non-fatal, allowing for ACPI Reduced Hardware 1480 * platforms which use GpioInt instead of GPE. 1481 */ 1482 1483 /* Use the global lock for all EC transactions? */ 1484 tmp = 0; 1485 acpi_evaluate_integer(handle, "_GLK", NULL, &tmp); 1486 ec->global_lock = tmp; 1487 ec->handle = handle; 1488 return AE_CTRL_TERMINATE; 1489 } 1490 1491 static bool install_gpe_event_handler(struct acpi_ec *ec) 1492 { 1493 acpi_status status; 1494 1495 status = acpi_install_gpe_raw_handler(NULL, ec->gpe, 1496 ACPI_GPE_EDGE_TRIGGERED, 1497 &acpi_ec_gpe_handler, ec); 1498 if (ACPI_FAILURE(status)) 1499 return false; 1500 1501 if (test_bit(EC_FLAGS_STARTED, &ec->flags) && ec->reference_count >= 1) 1502 acpi_ec_enable_gpe(ec, true); 1503 1504 return true; 1505 } 1506 1507 static bool install_gpio_irq_event_handler(struct acpi_ec *ec) 1508 { 1509 return request_threaded_irq(ec->irq, NULL, acpi_ec_irq_handler, 1510 IRQF_SHARED | IRQF_ONESHOT, "ACPI EC", ec) >= 0; 1511 } 1512 1513 /** 1514 * ec_install_handlers - Install service callbacks and register query methods. 1515 * @ec: Target EC. 1516 * @device: ACPI device object corresponding to @ec. 1517 * @call_reg: If _REG should be called to notify OpRegion availability 1518 * 1519 * Install a handler for the EC address space type unless it has been installed 1520 * already. If @device is not NULL, also look for EC query methods in the 1521 * namespace and register them, and install an event (either GPE or GPIO IRQ) 1522 * handler for the EC, if possible. 1523 * 1524 * Return: 1525 * -ENODEV if the address space handler cannot be installed, which means 1526 * "unable to handle transactions", 1527 * -EPROBE_DEFER if GPIO IRQ acquisition needs to be deferred, 1528 * or 0 (success) otherwise. 1529 */ 1530 static int ec_install_handlers(struct acpi_ec *ec, struct acpi_device *device, 1531 bool call_reg) 1532 { 1533 acpi_status status; 1534 1535 acpi_ec_start(ec, false); 1536 1537 if (!test_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags)) { 1538 acpi_handle scope_handle = ec == first_ec ? ACPI_ROOT_OBJECT : ec->handle; 1539 1540 acpi_ec_enter_noirq(ec); 1541 status = acpi_install_address_space_handler_no_reg(scope_handle, 1542 ACPI_ADR_SPACE_EC, 1543 &acpi_ec_space_handler, 1544 NULL, ec); 1545 if (ACPI_FAILURE(status)) { 1546 acpi_ec_stop(ec, false); 1547 return -ENODEV; 1548 } 1549 set_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags); 1550 } 1551 1552 if (call_reg && !test_bit(EC_FLAGS_EC_REG_CALLED, &ec->flags)) { 1553 acpi_execute_reg_methods(ec->handle, ACPI_UINT32_MAX, ACPI_ADR_SPACE_EC); 1554 set_bit(EC_FLAGS_EC_REG_CALLED, &ec->flags); 1555 } 1556 1557 if (!device) 1558 return 0; 1559 1560 if (ec->gpe < 0) { 1561 /* ACPI reduced hardware platforms use a GpioInt from _CRS. */ 1562 int irq = acpi_dev_gpio_irq_get(device, 0); 1563 /* 1564 * Bail out right away for deferred probing or complete the 1565 * initialization regardless of any other errors. 1566 */ 1567 if (irq == -EPROBE_DEFER) 1568 return -EPROBE_DEFER; 1569 else if (irq >= 0) 1570 ec->irq = irq; 1571 } 1572 1573 if (!test_bit(EC_FLAGS_QUERY_METHODS_INSTALLED, &ec->flags)) { 1574 /* Find and register all query methods */ 1575 acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1, 1576 acpi_ec_register_query_methods, 1577 NULL, ec, NULL); 1578 set_bit(EC_FLAGS_QUERY_METHODS_INSTALLED, &ec->flags); 1579 } 1580 if (!test_bit(EC_FLAGS_EVENT_HANDLER_INSTALLED, &ec->flags)) { 1581 bool ready = false; 1582 1583 if (ec->gpe >= 0) 1584 ready = install_gpe_event_handler(ec); 1585 else if (ec->irq >= 0) 1586 ready = install_gpio_irq_event_handler(ec); 1587 1588 if (ready) { 1589 set_bit(EC_FLAGS_EVENT_HANDLER_INSTALLED, &ec->flags); 1590 acpi_ec_leave_noirq(ec); 1591 } 1592 /* 1593 * Failures to install an event handler are not fatal, because 1594 * the EC can be polled for events. 1595 */ 1596 } 1597 /* EC is fully operational, allow queries */ 1598 acpi_ec_enable_event(ec); 1599 1600 return 0; 1601 } 1602 1603 static void ec_remove_handlers(struct acpi_ec *ec) 1604 { 1605 acpi_handle scope_handle = ec == first_ec ? ACPI_ROOT_OBJECT : ec->handle; 1606 1607 if (test_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags)) { 1608 if (ACPI_FAILURE(acpi_remove_address_space_handler( 1609 scope_handle, 1610 ACPI_ADR_SPACE_EC, 1611 &acpi_ec_space_handler))) 1612 pr_err("failed to remove space handler\n"); 1613 clear_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags); 1614 } 1615 1616 /* 1617 * Stops handling the EC transactions after removing the operation 1618 * region handler. This is required because _REG(DISCONNECT) 1619 * invoked during the removal can result in new EC transactions. 1620 * 1621 * Flushes the EC requests and thus disables the GPE before 1622 * removing the GPE handler. This is required by the current ACPICA 1623 * GPE core. ACPICA GPE core will automatically disable a GPE when 1624 * it is indicated but there is no way to handle it. So the drivers 1625 * must disable the GPEs prior to removing the GPE handlers. 1626 */ 1627 acpi_ec_stop(ec, false); 1628 1629 if (test_bit(EC_FLAGS_EVENT_HANDLER_INSTALLED, &ec->flags)) { 1630 if (ec->gpe >= 0 && 1631 ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe, 1632 &acpi_ec_gpe_handler))) 1633 pr_err("failed to remove gpe handler\n"); 1634 1635 if (ec->irq >= 0) 1636 free_irq(ec->irq, ec); 1637 1638 clear_bit(EC_FLAGS_EVENT_HANDLER_INSTALLED, &ec->flags); 1639 } 1640 if (test_bit(EC_FLAGS_QUERY_METHODS_INSTALLED, &ec->flags)) { 1641 acpi_ec_remove_query_handlers(ec, true, 0); 1642 clear_bit(EC_FLAGS_QUERY_METHODS_INSTALLED, &ec->flags); 1643 } 1644 } 1645 1646 static int acpi_ec_setup(struct acpi_ec *ec, struct acpi_device *device, bool call_reg) 1647 { 1648 int ret; 1649 1650 /* First EC capable of handling transactions */ 1651 if (!first_ec) 1652 first_ec = ec; 1653 1654 ret = ec_install_handlers(ec, device, call_reg); 1655 if (ret) { 1656 ec_remove_handlers(ec); 1657 1658 if (ec == first_ec) 1659 first_ec = NULL; 1660 1661 return ret; 1662 } 1663 1664 pr_info("EC_CMD/EC_SC=0x%lx, EC_DATA=0x%lx\n", ec->command_addr, 1665 ec->data_addr); 1666 1667 if (test_bit(EC_FLAGS_EVENT_HANDLER_INSTALLED, &ec->flags)) { 1668 if (ec->gpe >= 0) 1669 pr_info("GPE=0x%x\n", ec->gpe); 1670 else 1671 pr_info("IRQ=%d\n", ec->irq); 1672 } 1673 1674 return ret; 1675 } 1676 1677 static int acpi_ec_probe(struct platform_device *pdev) 1678 { 1679 struct acpi_device *device = ACPI_COMPANION(&pdev->dev); 1680 struct acpi_ec *ec; 1681 int ret; 1682 1683 if (boot_ec && (boot_ec->handle == device->handle || 1684 !strcmp(acpi_device_hid(device), ACPI_ECDT_HID))) { 1685 /* Fast path: this device corresponds to the boot EC. */ 1686 ec = boot_ec; 1687 } else { 1688 acpi_status status; 1689 1690 ec = acpi_ec_alloc(); 1691 if (!ec) 1692 return -ENOMEM; 1693 1694 status = ec_parse_device(device->handle, 0, ec, NULL); 1695 if (status != AE_CTRL_TERMINATE) { 1696 ret = -EINVAL; 1697 goto err; 1698 } 1699 1700 if (boot_ec && ec->command_addr == boot_ec->command_addr && 1701 ec->data_addr == boot_ec->data_addr) { 1702 /* 1703 * Trust PNP0C09 namespace location rather than ECDT ID. 1704 * But trust ECDT GPE rather than _GPE because of ASUS 1705 * quirks. So do not change boot_ec->gpe to ec->gpe, 1706 * except when the TRUST_DSDT_GPE quirk is set. 1707 */ 1708 boot_ec->handle = ec->handle; 1709 1710 if (EC_FLAGS_TRUST_DSDT_GPE) 1711 boot_ec->gpe = ec->gpe; 1712 1713 acpi_handle_debug(ec->handle, "duplicated.\n"); 1714 acpi_ec_free(ec); 1715 ec = boot_ec; 1716 } 1717 } 1718 1719 ret = acpi_ec_setup(ec, device, true); 1720 if (ret) 1721 goto err; 1722 1723 if (ec == boot_ec) 1724 acpi_handle_info(boot_ec->handle, 1725 "Boot %s EC initialization complete\n", 1726 boot_ec_is_ecdt ? "ECDT" : "DSDT"); 1727 1728 acpi_handle_info(ec->handle, 1729 "EC: Used to handle transactions and events\n"); 1730 1731 platform_set_drvdata(pdev, ec); 1732 1733 ret = !!request_region(ec->data_addr, 1, "EC data"); 1734 WARN(!ret, "Could not request EC data io port 0x%lx", ec->data_addr); 1735 ret = !!request_region(ec->command_addr, 1, "EC cmd"); 1736 WARN(!ret, "Could not request EC cmd io port 0x%lx", ec->command_addr); 1737 1738 /* Reprobe devices depending on the EC */ 1739 acpi_dev_clear_dependencies(device); 1740 1741 acpi_handle_debug(ec->handle, "enumerated.\n"); 1742 return 0; 1743 1744 err: 1745 if (ec != boot_ec) 1746 acpi_ec_free(ec); 1747 1748 return ret; 1749 } 1750 1751 static void acpi_ec_remove(struct platform_device *pdev) 1752 { 1753 struct acpi_ec *ec = platform_get_drvdata(pdev); 1754 1755 release_region(ec->data_addr, 1); 1756 release_region(ec->command_addr, 1); 1757 if (ec != boot_ec) { 1758 ec_remove_handlers(ec); 1759 acpi_ec_free(ec); 1760 } 1761 } 1762 1763 void acpi_ec_register_opregions(struct acpi_device *adev) 1764 { 1765 if (first_ec && first_ec->handle != adev->handle) 1766 acpi_execute_reg_methods(adev->handle, 1, ACPI_ADR_SPACE_EC); 1767 } 1768 1769 static acpi_status 1770 ec_parse_io_ports(struct acpi_resource *resource, void *context) 1771 { 1772 struct acpi_ec *ec = context; 1773 1774 if (resource->type != ACPI_RESOURCE_TYPE_IO) 1775 return AE_OK; 1776 1777 /* 1778 * The first address region returned is the data port, and 1779 * the second address region returned is the status/command 1780 * port. 1781 */ 1782 if (ec->data_addr == 0) 1783 ec->data_addr = resource->data.io.minimum; 1784 else if (ec->command_addr == 0) 1785 ec->command_addr = resource->data.io.minimum; 1786 else 1787 return AE_CTRL_TERMINATE; 1788 1789 return AE_OK; 1790 } 1791 1792 static const struct acpi_device_id ec_device_ids[] = { 1793 {"PNP0C09", 0}, 1794 {ACPI_ECDT_HID, 0}, 1795 {"", 0}, 1796 }; 1797 1798 /* 1799 * This function is not Windows-compatible as Windows never enumerates the 1800 * namespace EC before the main ACPI device enumeration process. It is 1801 * retained for historical reason and will be deprecated in the future. 1802 */ 1803 void __init acpi_ec_dsdt_probe(void) 1804 { 1805 struct acpi_ec *ec; 1806 acpi_status status; 1807 int ret; 1808 1809 /* 1810 * If a platform has ECDT, there is no need to proceed as the 1811 * following probe is not a part of the ACPI device enumeration, 1812 * executing _STA is not safe, and thus this probe may risk of 1813 * picking up an invalid EC device. 1814 */ 1815 if (boot_ec) 1816 return; 1817 1818 ec = acpi_ec_alloc(); 1819 if (!ec) 1820 return; 1821 1822 /* 1823 * At this point, the namespace is initialized, so start to find 1824 * the namespace objects. 1825 */ 1826 status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device, ec, NULL); 1827 if (ACPI_FAILURE(status) || !ec->handle) { 1828 acpi_ec_free(ec); 1829 return; 1830 } 1831 1832 /* 1833 * When the DSDT EC is available, always re-configure boot EC to 1834 * have _REG evaluated. _REG can only be evaluated after the 1835 * namespace initialization. 1836 * At this point, the GPE is not fully initialized, so do not to 1837 * handle the events. 1838 */ 1839 ret = acpi_ec_setup(ec, NULL, true); 1840 if (ret) { 1841 acpi_ec_free(ec); 1842 return; 1843 } 1844 1845 boot_ec = ec; 1846 1847 acpi_handle_info(ec->handle, 1848 "Boot DSDT EC used to handle transactions\n"); 1849 } 1850 1851 /* 1852 * acpi_ec_ecdt_start - Finalize the boot ECDT EC initialization. 1853 * 1854 * First, look for an ACPI handle for the boot ECDT EC if acpi_ec_add() has not 1855 * found a matching object in the namespace. 1856 * 1857 * Next, in case the DSDT EC is not functioning, it is still necessary to 1858 * provide a functional ECDT EC to handle events, so add an extra device object 1859 * to represent it (see https://bugzilla.kernel.org/show_bug.cgi?id=115021). 1860 * 1861 * This is useful on platforms with valid ECDT and invalid DSDT EC settings, 1862 * like ASUS X550ZE (see https://bugzilla.kernel.org/show_bug.cgi?id=196847). 1863 */ 1864 static void __init acpi_ec_ecdt_start(void) 1865 { 1866 struct acpi_table_ecdt *ecdt_ptr; 1867 acpi_handle handle; 1868 acpi_status status; 1869 1870 /* Bail out if a matching EC has been found in the namespace. */ 1871 if (!boot_ec || boot_ec->handle != ACPI_ROOT_OBJECT) 1872 return; 1873 1874 /* Look up the object pointed to from the ECDT in the namespace. */ 1875 status = acpi_get_table(ACPI_SIG_ECDT, 1, 1876 (struct acpi_table_header **)&ecdt_ptr); 1877 if (ACPI_FAILURE(status)) 1878 return; 1879 1880 status = acpi_get_handle(NULL, ecdt_ptr->id, &handle); 1881 if (ACPI_SUCCESS(status)) { 1882 boot_ec->handle = handle; 1883 1884 /* Add a special ACPI device object to represent the boot EC. */ 1885 acpi_bus_register_early_device(ACPI_BUS_TYPE_ECDT_EC); 1886 } 1887 1888 acpi_put_table((struct acpi_table_header *)ecdt_ptr); 1889 } 1890 1891 /* 1892 * On some hardware it is necessary to clear events accumulated by the EC during 1893 * sleep. These ECs stop reporting GPEs until they are manually polled, if too 1894 * many events are accumulated. (e.g. Samsung Series 5/9 notebooks) 1895 * 1896 * https://bugzilla.kernel.org/show_bug.cgi?id=44161 1897 * 1898 * Ideally, the EC should also be instructed NOT to accumulate events during 1899 * sleep (which Windows seems to do somehow), but the interface to control this 1900 * behaviour is not known at this time. 1901 * 1902 * Models known to be affected are Samsung 530Uxx/535Uxx/540Uxx/550Pxx/900Xxx, 1903 * however it is very likely that other Samsung models are affected. 1904 * 1905 * On systems which don't accumulate _Q events during sleep, this extra check 1906 * should be harmless. 1907 */ 1908 static int ec_clear_on_resume(const struct dmi_system_id *id) 1909 { 1910 pr_debug("Detected system needing EC poll on resume.\n"); 1911 EC_FLAGS_CLEAR_ON_RESUME = 1; 1912 ec_event_clearing = ACPI_EC_EVT_TIMING_STATUS; 1913 return 0; 1914 } 1915 1916 /* 1917 * Some ECDTs contain wrong register addresses. 1918 * MSI MS-171F 1919 * https://bugzilla.kernel.org/show_bug.cgi?id=12461 1920 */ 1921 static int ec_correct_ecdt(const struct dmi_system_id *id) 1922 { 1923 pr_debug("Detected system needing ECDT address correction.\n"); 1924 EC_FLAGS_CORRECT_ECDT = 1; 1925 return 0; 1926 } 1927 1928 /* 1929 * Some ECDTs contain wrong GPE setting, but they share the same port addresses 1930 * with DSDT EC, don't duplicate the DSDT EC with ECDT EC in this case. 1931 * https://bugzilla.kernel.org/show_bug.cgi?id=209989 1932 */ 1933 static int ec_honor_dsdt_gpe(const struct dmi_system_id *id) 1934 { 1935 pr_debug("Detected system needing DSDT GPE setting.\n"); 1936 EC_FLAGS_TRUST_DSDT_GPE = 1; 1937 return 0; 1938 } 1939 1940 static const struct dmi_system_id ec_dmi_table[] __initconst = { 1941 { 1942 /* 1943 * MSI MS-171F 1944 * https://bugzilla.kernel.org/show_bug.cgi?id=12461 1945 */ 1946 .callback = ec_correct_ecdt, 1947 .matches = { 1948 DMI_MATCH(DMI_SYS_VENDOR, "Micro-Star"), 1949 DMI_MATCH(DMI_PRODUCT_NAME, "MS-171F"), 1950 }, 1951 }, 1952 { 1953 /* 1954 * HP Pavilion Gaming Laptop 15-cx0xxx 1955 * https://bugzilla.kernel.org/show_bug.cgi?id=209989 1956 */ 1957 .callback = ec_honor_dsdt_gpe, 1958 .matches = { 1959 DMI_MATCH(DMI_SYS_VENDOR, "HP"), 1960 DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion Gaming Laptop 15-cx0xxx"), 1961 }, 1962 }, 1963 { 1964 /* 1965 * HP Pavilion Gaming Laptop 15-cx0041ur 1966 */ 1967 .callback = ec_honor_dsdt_gpe, 1968 .matches = { 1969 DMI_MATCH(DMI_SYS_VENDOR, "HP"), 1970 DMI_MATCH(DMI_PRODUCT_NAME, "HP 15-cx0041ur"), 1971 }, 1972 }, 1973 { 1974 /* 1975 * HP Pavilion Gaming Laptop 15-dk1xxx 1976 * https://github.com/systemd/systemd/issues/28942 1977 */ 1978 .callback = ec_honor_dsdt_gpe, 1979 .matches = { 1980 DMI_MATCH(DMI_SYS_VENDOR, "HP"), 1981 DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion Gaming Laptop 15-dk1xxx"), 1982 }, 1983 }, 1984 { 1985 /* 1986 * HP 250 G7 Notebook PC 1987 */ 1988 .callback = ec_honor_dsdt_gpe, 1989 .matches = { 1990 DMI_MATCH(DMI_SYS_VENDOR, "HP"), 1991 DMI_MATCH(DMI_PRODUCT_NAME, "HP 250 G7 Notebook PC"), 1992 }, 1993 }, 1994 { 1995 /* 1996 * Samsung hardware 1997 * https://bugzilla.kernel.org/show_bug.cgi?id=44161 1998 */ 1999 .callback = ec_clear_on_resume, 2000 .matches = { 2001 DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."), 2002 }, 2003 }, 2004 {} 2005 }; 2006 2007 void __init acpi_ec_ecdt_probe(void) 2008 { 2009 struct acpi_table_ecdt *ecdt_ptr; 2010 struct acpi_ec *ec; 2011 acpi_status status; 2012 int ret; 2013 2014 /* Generate a boot ec context. */ 2015 dmi_check_system(ec_dmi_table); 2016 status = acpi_get_table(ACPI_SIG_ECDT, 1, 2017 (struct acpi_table_header **)&ecdt_ptr); 2018 if (ACPI_FAILURE(status)) 2019 return; 2020 2021 if (!ecdt_ptr->control.address || !ecdt_ptr->data.address) { 2022 /* 2023 * Asus X50GL: 2024 * https://bugzilla.kernel.org/show_bug.cgi?id=11880 2025 */ 2026 goto out; 2027 } 2028 2029 if (!strlen(ecdt_ptr->id)) { 2030 /* 2031 * The ECDT table on some MSI notebooks contains invalid data, together 2032 * with an empty ID string (""). 2033 * 2034 * Section 5.2.15 of the ACPI specification requires the ID string to be 2035 * a "fully qualified reference to the (...) embedded controller device", 2036 * so this string always has to start with a backslash. 2037 * 2038 * However some ThinkBook machines have a ECDT table with a valid EC 2039 * description but an invalid ID string ("_SB.PC00.LPCB.EC0"). 2040 * 2041 * Because of this we only check if the ID string is empty in order to 2042 * avoid the obvious cases. 2043 */ 2044 pr_err(FW_BUG "Ignoring ECDT due to empty ID string\n"); 2045 goto out; 2046 } 2047 2048 ec = acpi_ec_alloc(); 2049 if (!ec) 2050 goto out; 2051 2052 if (EC_FLAGS_CORRECT_ECDT) { 2053 ec->command_addr = ecdt_ptr->data.address; 2054 ec->data_addr = ecdt_ptr->control.address; 2055 } else { 2056 ec->command_addr = ecdt_ptr->control.address; 2057 ec->data_addr = ecdt_ptr->data.address; 2058 } 2059 2060 /* 2061 * Ignore the GPE value on Reduced Hardware platforms. 2062 * Some products have this set to an erroneous value. 2063 */ 2064 if (!acpi_gbl_reduced_hardware) 2065 ec->gpe = ecdt_ptr->gpe; 2066 2067 ec->handle = ACPI_ROOT_OBJECT; 2068 2069 /* 2070 * At this point, the namespace is not initialized, so do not find 2071 * the namespace objects, or handle the events. 2072 */ 2073 ret = acpi_ec_setup(ec, NULL, false); 2074 if (ret) { 2075 acpi_ec_free(ec); 2076 goto out; 2077 } 2078 2079 boot_ec = ec; 2080 boot_ec_is_ecdt = true; 2081 2082 pr_info("Boot ECDT EC used to handle transactions\n"); 2083 2084 out: 2085 acpi_put_table((struct acpi_table_header *)ecdt_ptr); 2086 } 2087 2088 #ifdef CONFIG_PM_SLEEP 2089 static int acpi_ec_suspend(struct device *dev) 2090 { 2091 struct acpi_ec *ec = dev_get_drvdata(dev); 2092 2093 if (!pm_suspend_no_platform() && ec_freeze_events) 2094 acpi_ec_disable_event(ec); 2095 return 0; 2096 } 2097 2098 static int acpi_ec_suspend_noirq(struct device *dev) 2099 { 2100 struct acpi_ec *ec = dev_get_drvdata(dev); 2101 2102 /* 2103 * The SCI handler doesn't run at this point, so the GPE can be 2104 * masked at the low level without side effects. 2105 */ 2106 if (ec_no_wakeup && test_bit(EC_FLAGS_STARTED, &ec->flags) && 2107 ec->gpe >= 0 && ec->reference_count >= 1) 2108 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_DISABLE); 2109 2110 acpi_ec_enter_noirq(ec); 2111 2112 return 0; 2113 } 2114 2115 static int acpi_ec_resume_noirq(struct device *dev) 2116 { 2117 struct acpi_ec *ec = dev_get_drvdata(dev); 2118 2119 acpi_ec_leave_noirq(ec); 2120 2121 if (ec_no_wakeup && test_bit(EC_FLAGS_STARTED, &ec->flags) && 2122 ec->gpe >= 0 && ec->reference_count >= 1) 2123 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_ENABLE); 2124 2125 return 0; 2126 } 2127 2128 static int acpi_ec_resume(struct device *dev) 2129 { 2130 struct acpi_ec *ec = dev_get_drvdata(dev); 2131 2132 acpi_ec_enable_event(ec); 2133 return 0; 2134 } 2135 2136 void acpi_ec_mark_gpe_for_wake(void) 2137 { 2138 if (first_ec && !ec_no_wakeup) 2139 acpi_mark_gpe_for_wake(NULL, first_ec->gpe); 2140 } 2141 EXPORT_SYMBOL_GPL(acpi_ec_mark_gpe_for_wake); 2142 2143 void acpi_ec_set_gpe_wake_mask(u8 action) 2144 { 2145 if (pm_suspend_no_platform() && first_ec && !ec_no_wakeup) 2146 acpi_set_gpe_wake_mask(NULL, first_ec->gpe, action); 2147 } 2148 2149 static bool acpi_ec_work_in_progress(struct acpi_ec *ec) 2150 { 2151 return ec->events_in_progress + ec->queries_in_progress > 0; 2152 } 2153 2154 bool acpi_ec_dispatch_gpe(void) 2155 { 2156 bool work_in_progress = false; 2157 2158 if (!first_ec) 2159 return acpi_any_gpe_status_set(U32_MAX); 2160 2161 /* 2162 * Report wakeup if the status bit is set for any enabled GPE other 2163 * than the EC one. 2164 */ 2165 if (acpi_any_gpe_status_set(first_ec->gpe)) 2166 return true; 2167 2168 /* 2169 * Cancel the SCI wakeup and process all pending events in case there 2170 * are any wakeup ones in there. 2171 * 2172 * Note that if any non-EC GPEs are active at this point, the SCI will 2173 * retrigger after the rearming in acpi_s2idle_wake(), so no events 2174 * should be missed by canceling the wakeup here. 2175 */ 2176 pm_system_cancel_wakeup(); 2177 2178 /* 2179 * Dispatch the EC GPE in-band, but do not report wakeup in any case 2180 * to allow the caller to process events properly after that. 2181 */ 2182 spin_lock_irq(&first_ec->lock); 2183 2184 if (acpi_ec_gpe_status_set(first_ec)) { 2185 pm_pr_dbg("ACPI EC GPE status set\n"); 2186 2187 clear_gpe_and_advance_transaction(first_ec, false); 2188 work_in_progress = acpi_ec_work_in_progress(first_ec); 2189 } 2190 2191 spin_unlock_irq(&first_ec->lock); 2192 2193 if (!work_in_progress) 2194 return false; 2195 2196 pm_pr_dbg("ACPI EC GPE dispatched\n"); 2197 2198 /* Drain EC work. */ 2199 do { 2200 acpi_ec_flush_work(); 2201 2202 pm_pr_dbg("ACPI EC work flushed\n"); 2203 2204 spin_lock_irq(&first_ec->lock); 2205 2206 work_in_progress = acpi_ec_work_in_progress(first_ec); 2207 2208 spin_unlock_irq(&first_ec->lock); 2209 } while (work_in_progress && !pm_wakeup_pending()); 2210 2211 return false; 2212 } 2213 #endif /* CONFIG_PM_SLEEP */ 2214 2215 static const struct dev_pm_ops acpi_ec_pm = { 2216 SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(acpi_ec_suspend_noirq, acpi_ec_resume_noirq) 2217 SET_SYSTEM_SLEEP_PM_OPS(acpi_ec_suspend, acpi_ec_resume) 2218 }; 2219 2220 static int param_set_event_clearing(const char *val, 2221 const struct kernel_param *kp) 2222 { 2223 int result = 0; 2224 2225 if (!strncmp(val, "status", sizeof("status") - 1)) { 2226 ec_event_clearing = ACPI_EC_EVT_TIMING_STATUS; 2227 pr_info("Assuming SCI_EVT clearing on EC_SC accesses\n"); 2228 } else if (!strncmp(val, "query", sizeof("query") - 1)) { 2229 ec_event_clearing = ACPI_EC_EVT_TIMING_QUERY; 2230 pr_info("Assuming SCI_EVT clearing on QR_EC writes\n"); 2231 } else if (!strncmp(val, "event", sizeof("event") - 1)) { 2232 ec_event_clearing = ACPI_EC_EVT_TIMING_EVENT; 2233 pr_info("Assuming SCI_EVT clearing on event reads\n"); 2234 } else 2235 result = -EINVAL; 2236 return result; 2237 } 2238 2239 static int param_get_event_clearing(char *buffer, 2240 const struct kernel_param *kp) 2241 { 2242 switch (ec_event_clearing) { 2243 case ACPI_EC_EVT_TIMING_STATUS: 2244 return sprintf(buffer, "status\n"); 2245 case ACPI_EC_EVT_TIMING_QUERY: 2246 return sprintf(buffer, "query\n"); 2247 case ACPI_EC_EVT_TIMING_EVENT: 2248 return sprintf(buffer, "event\n"); 2249 default: 2250 return sprintf(buffer, "invalid\n"); 2251 } 2252 return 0; 2253 } 2254 2255 module_param_call(ec_event_clearing, param_set_event_clearing, param_get_event_clearing, 2256 NULL, 0644); 2257 MODULE_PARM_DESC(ec_event_clearing, "Assumed SCI_EVT clearing timing"); 2258 2259 static struct platform_driver acpi_ec_driver = { 2260 .probe = acpi_ec_probe, 2261 .remove = acpi_ec_remove, 2262 .driver = { 2263 .name = "acpi-ec", 2264 .acpi_match_table = ec_device_ids, 2265 .pm = &acpi_ec_pm, 2266 }, 2267 }; 2268 2269 static void acpi_ec_destroy_workqueues(void) 2270 { 2271 if (ec_wq) { 2272 destroy_workqueue(ec_wq); 2273 ec_wq = NULL; 2274 } 2275 if (ec_query_wq) { 2276 destroy_workqueue(ec_query_wq); 2277 ec_query_wq = NULL; 2278 } 2279 } 2280 2281 static int acpi_ec_init_workqueues(void) 2282 { 2283 if (!ec_wq) 2284 ec_wq = alloc_ordered_workqueue("kec", 0); 2285 2286 if (!ec_query_wq) 2287 ec_query_wq = alloc_workqueue("kec_query", WQ_PERCPU, 2288 ec_max_queries); 2289 2290 if (!ec_wq || !ec_query_wq) { 2291 acpi_ec_destroy_workqueues(); 2292 return -ENODEV; 2293 } 2294 return 0; 2295 } 2296 2297 static const struct dmi_system_id acpi_ec_no_wakeup[] = { 2298 { 2299 .matches = { 2300 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"), 2301 DMI_MATCH(DMI_PRODUCT_FAMILY, "Thinkpad X1 Carbon 6th"), 2302 }, 2303 }, 2304 { 2305 .matches = { 2306 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"), 2307 DMI_MATCH(DMI_PRODUCT_FAMILY, "ThinkPad X1 Yoga 3rd"), 2308 }, 2309 }, 2310 { 2311 .matches = { 2312 DMI_MATCH(DMI_SYS_VENDOR, "HP"), 2313 DMI_MATCH(DMI_PRODUCT_FAMILY, "103C_5336AN HP ZHAN 66 Pro"), 2314 }, 2315 }, 2316 /* 2317 * Lenovo Legion Go S; touchscreen blocks HW sleep when woken up from EC 2318 * https://gitlab.freedesktop.org/drm/amd/-/issues/3929 2319 */ 2320 { 2321 .matches = { 2322 DMI_MATCH(DMI_BOARD_VENDOR, "LENOVO"), 2323 DMI_MATCH(DMI_PRODUCT_NAME, "83L3"), 2324 } 2325 }, 2326 { 2327 .matches = { 2328 DMI_MATCH(DMI_BOARD_VENDOR, "LENOVO"), 2329 DMI_MATCH(DMI_PRODUCT_NAME, "83N6"), 2330 } 2331 }, 2332 { 2333 .matches = { 2334 DMI_MATCH(DMI_BOARD_VENDOR, "LENOVO"), 2335 DMI_MATCH(DMI_PRODUCT_NAME, "83Q2"), 2336 } 2337 }, 2338 { 2339 .matches = { 2340 DMI_MATCH(DMI_BOARD_VENDOR, "LENOVO"), 2341 DMI_MATCH(DMI_PRODUCT_NAME, "83Q3"), 2342 } 2343 }, 2344 { 2345 // TUXEDO InfinityBook Pro AMD Gen9 2346 .matches = { 2347 DMI_MATCH(DMI_BOARD_NAME, "GXxHRXx"), 2348 }, 2349 }, 2350 { }, 2351 }; 2352 2353 void __init acpi_ec_init(void) 2354 { 2355 int result; 2356 2357 result = acpi_ec_init_workqueues(); 2358 if (result) 2359 return; 2360 2361 /* 2362 * Disable EC wakeup on following systems to prevent periodic 2363 * wakeup from EC GPE. 2364 */ 2365 if (dmi_check_system(acpi_ec_no_wakeup)) { 2366 ec_no_wakeup = true; 2367 pr_debug("Disabling EC wakeup on suspend-to-idle\n"); 2368 } 2369 2370 /* Driver must be registered after acpi_ec_init_workqueues(). */ 2371 platform_driver_register(&acpi_ec_driver); 2372 2373 acpi_ec_ecdt_start(); 2374 } 2375