1 /* 2 * ec.c - ACPI Embedded Controller Driver (v3) 3 * 4 * Copyright (C) 2001-2015 Intel Corporation 5 * Author: 2014, 2015 Lv Zheng <lv.zheng@intel.com> 6 * 2006, 2007 Alexey Starikovskiy <alexey.y.starikovskiy@intel.com> 7 * 2006 Denis Sadykov <denis.m.sadykov@intel.com> 8 * 2004 Luming Yu <luming.yu@intel.com> 9 * 2001, 2002 Andy Grover <andrew.grover@intel.com> 10 * 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com> 11 * Copyright (C) 2008 Alexey Starikovskiy <astarikovskiy@suse.de> 12 * 13 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 14 * 15 * This program is free software; you can redistribute it and/or modify 16 * it under the terms of the GNU General Public License as published by 17 * the Free Software Foundation; either version 2 of the License, or (at 18 * your option) any later version. 19 * 20 * This program is distributed in the hope that it will be useful, but 21 * WITHOUT ANY WARRANTY; without even the implied warranty of 22 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 23 * General Public License for more details. 24 * 25 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 26 */ 27 28 /* Uncomment next line to get verbose printout */ 29 /* #define DEBUG */ 30 #define pr_fmt(fmt) "ACPI : EC: " fmt 31 32 #include <linux/kernel.h> 33 #include <linux/module.h> 34 #include <linux/init.h> 35 #include <linux/types.h> 36 #include <linux/delay.h> 37 #include <linux/interrupt.h> 38 #include <linux/list.h> 39 #include <linux/spinlock.h> 40 #include <linux/slab.h> 41 #include <linux/acpi.h> 42 #include <linux/dmi.h> 43 #include <asm/io.h> 44 45 #include "internal.h" 46 47 #define ACPI_EC_CLASS "embedded_controller" 48 #define ACPI_EC_DEVICE_NAME "Embedded Controller" 49 #define ACPI_EC_FILE_INFO "info" 50 51 /* EC status register */ 52 #define ACPI_EC_FLAG_OBF 0x01 /* Output buffer full */ 53 #define ACPI_EC_FLAG_IBF 0x02 /* Input buffer full */ 54 #define ACPI_EC_FLAG_CMD 0x08 /* Input buffer contains a command */ 55 #define ACPI_EC_FLAG_BURST 0x10 /* burst mode */ 56 #define ACPI_EC_FLAG_SCI 0x20 /* EC-SCI occurred */ 57 58 /* 59 * The SCI_EVT clearing timing is not defined by the ACPI specification. 60 * This leads to lots of practical timing issues for the host EC driver. 61 * The following variations are defined (from the target EC firmware's 62 * perspective): 63 * STATUS: After indicating SCI_EVT edge triggered IRQ to the host, the 64 * target can clear SCI_EVT at any time so long as the host can see 65 * the indication by reading the status register (EC_SC). So the 66 * host should re-check SCI_EVT after the first time the SCI_EVT 67 * indication is seen, which is the same time the query request 68 * (QR_EC) is written to the command register (EC_CMD). SCI_EVT set 69 * at any later time could indicate another event. Normally such 70 * kind of EC firmware has implemented an event queue and will 71 * return 0x00 to indicate "no outstanding event". 72 * QUERY: After seeing the query request (QR_EC) written to the command 73 * register (EC_CMD) by the host and having prepared the responding 74 * event value in the data register (EC_DATA), the target can safely 75 * clear SCI_EVT because the target can confirm that the current 76 * event is being handled by the host. The host then should check 77 * SCI_EVT right after reading the event response from the data 78 * register (EC_DATA). 79 * EVENT: After seeing the event response read from the data register 80 * (EC_DATA) by the host, the target can clear SCI_EVT. As the 81 * target requires time to notice the change in the data register 82 * (EC_DATA), the host may be required to wait additional guarding 83 * time before checking the SCI_EVT again. Such guarding may not be 84 * necessary if the host is notified via another IRQ. 85 */ 86 #define ACPI_EC_EVT_TIMING_STATUS 0x00 87 #define ACPI_EC_EVT_TIMING_QUERY 0x01 88 #define ACPI_EC_EVT_TIMING_EVENT 0x02 89 90 /* EC commands */ 91 enum ec_command { 92 ACPI_EC_COMMAND_READ = 0x80, 93 ACPI_EC_COMMAND_WRITE = 0x81, 94 ACPI_EC_BURST_ENABLE = 0x82, 95 ACPI_EC_BURST_DISABLE = 0x83, 96 ACPI_EC_COMMAND_QUERY = 0x84, 97 }; 98 99 #define ACPI_EC_DELAY 500 /* Wait 500ms max. during EC ops */ 100 #define ACPI_EC_UDELAY_GLK 1000 /* Wait 1ms max. to get global lock */ 101 #define ACPI_EC_UDELAY_POLL 550 /* Wait 1ms for EC transaction polling */ 102 #define ACPI_EC_CLEAR_MAX 100 /* Maximum number of events to query 103 * when trying to clear the EC */ 104 #define ACPI_EC_MAX_QUERIES 16 /* Maximum number of parallel queries */ 105 106 enum { 107 EC_FLAGS_QUERY_PENDING, /* Query is pending */ 108 EC_FLAGS_QUERY_GUARDING, /* Guard for SCI_EVT check */ 109 EC_FLAGS_GPE_HANDLER_INSTALLED, /* GPE handler installed */ 110 EC_FLAGS_EC_HANDLER_INSTALLED, /* OpReg handler installed */ 111 EC_FLAGS_STARTED, /* Driver is started */ 112 EC_FLAGS_STOPPED, /* Driver is stopped */ 113 EC_FLAGS_COMMAND_STORM, /* GPE storms occurred to the 114 * current command processing */ 115 }; 116 117 #define ACPI_EC_COMMAND_POLL 0x01 /* Available for command byte */ 118 #define ACPI_EC_COMMAND_COMPLETE 0x02 /* Completed last byte */ 119 120 /* ec.c is compiled in acpi namespace so this shows up as acpi.ec_delay param */ 121 static unsigned int ec_delay __read_mostly = ACPI_EC_DELAY; 122 module_param(ec_delay, uint, 0644); 123 MODULE_PARM_DESC(ec_delay, "Timeout(ms) waited until an EC command completes"); 124 125 static unsigned int ec_max_queries __read_mostly = ACPI_EC_MAX_QUERIES; 126 module_param(ec_max_queries, uint, 0644); 127 MODULE_PARM_DESC(ec_max_queries, "Maximum parallel _Qxx evaluations"); 128 129 static bool ec_busy_polling __read_mostly; 130 module_param(ec_busy_polling, bool, 0644); 131 MODULE_PARM_DESC(ec_busy_polling, "Use busy polling to advance EC transaction"); 132 133 static unsigned int ec_polling_guard __read_mostly = ACPI_EC_UDELAY_POLL; 134 module_param(ec_polling_guard, uint, 0644); 135 MODULE_PARM_DESC(ec_polling_guard, "Guard time(us) between EC accesses in polling modes"); 136 137 static unsigned int ec_event_clearing __read_mostly = ACPI_EC_EVT_TIMING_QUERY; 138 139 /* 140 * If the number of false interrupts per one transaction exceeds 141 * this threshold, will think there is a GPE storm happened and 142 * will disable the GPE for normal transaction. 143 */ 144 static unsigned int ec_storm_threshold __read_mostly = 8; 145 module_param(ec_storm_threshold, uint, 0644); 146 MODULE_PARM_DESC(ec_storm_threshold, "Maxim false GPE numbers not considered as GPE storm"); 147 148 struct acpi_ec_query_handler { 149 struct list_head node; 150 acpi_ec_query_func func; 151 acpi_handle handle; 152 void *data; 153 u8 query_bit; 154 struct kref kref; 155 }; 156 157 struct transaction { 158 const u8 *wdata; 159 u8 *rdata; 160 unsigned short irq_count; 161 u8 command; 162 u8 wi; 163 u8 ri; 164 u8 wlen; 165 u8 rlen; 166 u8 flags; 167 }; 168 169 struct acpi_ec_query { 170 struct transaction transaction; 171 struct work_struct work; 172 struct acpi_ec_query_handler *handler; 173 }; 174 175 static int acpi_ec_query(struct acpi_ec *ec, u8 *data); 176 static void advance_transaction(struct acpi_ec *ec); 177 static void acpi_ec_event_handler(struct work_struct *work); 178 static void acpi_ec_event_processor(struct work_struct *work); 179 180 struct acpi_ec *boot_ec, *first_ec; 181 EXPORT_SYMBOL(first_ec); 182 static struct workqueue_struct *ec_query_wq; 183 184 static int EC_FLAGS_CLEAR_ON_RESUME; /* Needs acpi_ec_clear() on boot/resume */ 185 static int EC_FLAGS_QUERY_HANDSHAKE; /* Needs QR_EC issued when SCI_EVT set */ 186 static int EC_FLAGS_CORRECT_ECDT; /* Needs ECDT port address correction */ 187 188 /* -------------------------------------------------------------------------- 189 * Logging/Debugging 190 * -------------------------------------------------------------------------- */ 191 192 /* 193 * Splitters used by the developers to track the boundary of the EC 194 * handling processes. 195 */ 196 #ifdef DEBUG 197 #define EC_DBG_SEP " " 198 #define EC_DBG_DRV "+++++" 199 #define EC_DBG_STM "=====" 200 #define EC_DBG_REQ "*****" 201 #define EC_DBG_EVT "#####" 202 #else 203 #define EC_DBG_SEP "" 204 #define EC_DBG_DRV 205 #define EC_DBG_STM 206 #define EC_DBG_REQ 207 #define EC_DBG_EVT 208 #endif 209 210 #define ec_log_raw(fmt, ...) \ 211 pr_info(fmt "\n", ##__VA_ARGS__) 212 #define ec_dbg_raw(fmt, ...) \ 213 pr_debug(fmt "\n", ##__VA_ARGS__) 214 #define ec_log(filter, fmt, ...) \ 215 ec_log_raw(filter EC_DBG_SEP fmt EC_DBG_SEP filter, ##__VA_ARGS__) 216 #define ec_dbg(filter, fmt, ...) \ 217 ec_dbg_raw(filter EC_DBG_SEP fmt EC_DBG_SEP filter, ##__VA_ARGS__) 218 219 #define ec_log_drv(fmt, ...) \ 220 ec_log(EC_DBG_DRV, fmt, ##__VA_ARGS__) 221 #define ec_dbg_drv(fmt, ...) \ 222 ec_dbg(EC_DBG_DRV, fmt, ##__VA_ARGS__) 223 #define ec_dbg_stm(fmt, ...) \ 224 ec_dbg(EC_DBG_STM, fmt, ##__VA_ARGS__) 225 #define ec_dbg_req(fmt, ...) \ 226 ec_dbg(EC_DBG_REQ, fmt, ##__VA_ARGS__) 227 #define ec_dbg_evt(fmt, ...) \ 228 ec_dbg(EC_DBG_EVT, fmt, ##__VA_ARGS__) 229 #define ec_dbg_ref(ec, fmt, ...) \ 230 ec_dbg_raw("%lu: " fmt, ec->reference_count, ## __VA_ARGS__) 231 232 /* -------------------------------------------------------------------------- 233 * Device Flags 234 * -------------------------------------------------------------------------- */ 235 236 static bool acpi_ec_started(struct acpi_ec *ec) 237 { 238 return test_bit(EC_FLAGS_STARTED, &ec->flags) && 239 !test_bit(EC_FLAGS_STOPPED, &ec->flags); 240 } 241 242 static bool acpi_ec_flushed(struct acpi_ec *ec) 243 { 244 return ec->reference_count == 1; 245 } 246 247 /* -------------------------------------------------------------------------- 248 * EC Registers 249 * -------------------------------------------------------------------------- */ 250 251 static inline u8 acpi_ec_read_status(struct acpi_ec *ec) 252 { 253 u8 x = inb(ec->command_addr); 254 255 ec_dbg_raw("EC_SC(R) = 0x%2.2x " 256 "SCI_EVT=%d BURST=%d CMD=%d IBF=%d OBF=%d", 257 x, 258 !!(x & ACPI_EC_FLAG_SCI), 259 !!(x & ACPI_EC_FLAG_BURST), 260 !!(x & ACPI_EC_FLAG_CMD), 261 !!(x & ACPI_EC_FLAG_IBF), 262 !!(x & ACPI_EC_FLAG_OBF)); 263 return x; 264 } 265 266 static inline u8 acpi_ec_read_data(struct acpi_ec *ec) 267 { 268 u8 x = inb(ec->data_addr); 269 270 ec->timestamp = jiffies; 271 ec_dbg_raw("EC_DATA(R) = 0x%2.2x", x); 272 return x; 273 } 274 275 static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command) 276 { 277 ec_dbg_raw("EC_SC(W) = 0x%2.2x", command); 278 outb(command, ec->command_addr); 279 ec->timestamp = jiffies; 280 } 281 282 static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data) 283 { 284 ec_dbg_raw("EC_DATA(W) = 0x%2.2x", data); 285 outb(data, ec->data_addr); 286 ec->timestamp = jiffies; 287 } 288 289 #ifdef DEBUG 290 static const char *acpi_ec_cmd_string(u8 cmd) 291 { 292 switch (cmd) { 293 case 0x80: 294 return "RD_EC"; 295 case 0x81: 296 return "WR_EC"; 297 case 0x82: 298 return "BE_EC"; 299 case 0x83: 300 return "BD_EC"; 301 case 0x84: 302 return "QR_EC"; 303 } 304 return "UNKNOWN"; 305 } 306 #else 307 #define acpi_ec_cmd_string(cmd) "UNDEF" 308 #endif 309 310 /* -------------------------------------------------------------------------- 311 * GPE Registers 312 * -------------------------------------------------------------------------- */ 313 314 static inline bool acpi_ec_is_gpe_raised(struct acpi_ec *ec) 315 { 316 acpi_event_status gpe_status = 0; 317 318 (void)acpi_get_gpe_status(NULL, ec->gpe, &gpe_status); 319 return (gpe_status & ACPI_EVENT_FLAG_STATUS_SET) ? true : false; 320 } 321 322 static inline void acpi_ec_enable_gpe(struct acpi_ec *ec, bool open) 323 { 324 if (open) 325 acpi_enable_gpe(NULL, ec->gpe); 326 else { 327 BUG_ON(ec->reference_count < 1); 328 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_ENABLE); 329 } 330 if (acpi_ec_is_gpe_raised(ec)) { 331 /* 332 * On some platforms, EN=1 writes cannot trigger GPE. So 333 * software need to manually trigger a pseudo GPE event on 334 * EN=1 writes. 335 */ 336 ec_dbg_raw("Polling quirk"); 337 advance_transaction(ec); 338 } 339 } 340 341 static inline void acpi_ec_disable_gpe(struct acpi_ec *ec, bool close) 342 { 343 if (close) 344 acpi_disable_gpe(NULL, ec->gpe); 345 else { 346 BUG_ON(ec->reference_count < 1); 347 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_DISABLE); 348 } 349 } 350 351 static inline void acpi_ec_clear_gpe(struct acpi_ec *ec) 352 { 353 /* 354 * GPE STS is a W1C register, which means: 355 * 1. Software can clear it without worrying about clearing other 356 * GPEs' STS bits when the hardware sets them in parallel. 357 * 2. As long as software can ensure only clearing it when it is 358 * set, hardware won't set it in parallel. 359 * So software can clear GPE in any contexts. 360 * Warning: do not move the check into advance_transaction() as the 361 * EC commands will be sent without GPE raised. 362 */ 363 if (!acpi_ec_is_gpe_raised(ec)) 364 return; 365 acpi_clear_gpe(NULL, ec->gpe); 366 } 367 368 /* -------------------------------------------------------------------------- 369 * Transaction Management 370 * -------------------------------------------------------------------------- */ 371 372 static void acpi_ec_submit_request(struct acpi_ec *ec) 373 { 374 ec->reference_count++; 375 if (test_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags) && 376 ec->reference_count == 1) 377 acpi_ec_enable_gpe(ec, true); 378 } 379 380 static void acpi_ec_complete_request(struct acpi_ec *ec) 381 { 382 bool flushed = false; 383 384 ec->reference_count--; 385 if (test_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags) && 386 ec->reference_count == 0) 387 acpi_ec_disable_gpe(ec, true); 388 flushed = acpi_ec_flushed(ec); 389 if (flushed) 390 wake_up(&ec->wait); 391 } 392 393 static void acpi_ec_set_storm(struct acpi_ec *ec, u8 flag) 394 { 395 if (!test_bit(flag, &ec->flags)) { 396 acpi_ec_disable_gpe(ec, false); 397 ec_dbg_drv("Polling enabled"); 398 set_bit(flag, &ec->flags); 399 } 400 } 401 402 static void acpi_ec_clear_storm(struct acpi_ec *ec, u8 flag) 403 { 404 if (test_bit(flag, &ec->flags)) { 405 clear_bit(flag, &ec->flags); 406 acpi_ec_enable_gpe(ec, false); 407 ec_dbg_drv("Polling disabled"); 408 } 409 } 410 411 /* 412 * acpi_ec_submit_flushable_request() - Increase the reference count unless 413 * the flush operation is not in 414 * progress 415 * @ec: the EC device 416 * 417 * This function must be used before taking a new action that should hold 418 * the reference count. If this function returns false, then the action 419 * must be discarded or it will prevent the flush operation from being 420 * completed. 421 */ 422 static bool acpi_ec_submit_flushable_request(struct acpi_ec *ec) 423 { 424 if (!acpi_ec_started(ec)) 425 return false; 426 acpi_ec_submit_request(ec); 427 return true; 428 } 429 430 static void acpi_ec_submit_query(struct acpi_ec *ec) 431 { 432 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) { 433 ec_dbg_evt("Command(%s) submitted/blocked", 434 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY)); 435 ec->nr_pending_queries++; 436 schedule_work(&ec->work); 437 } 438 } 439 440 static void acpi_ec_complete_query(struct acpi_ec *ec) 441 { 442 if (test_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) { 443 clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags); 444 ec_dbg_evt("Command(%s) unblocked", 445 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY)); 446 } 447 } 448 449 static bool acpi_ec_guard_event(struct acpi_ec *ec) 450 { 451 bool guarded = true; 452 unsigned long flags; 453 454 spin_lock_irqsave(&ec->lock, flags); 455 /* 456 * If firmware SCI_EVT clearing timing is "event", we actually 457 * don't know when the SCI_EVT will be cleared by firmware after 458 * evaluating _Qxx, so we need to re-check SCI_EVT after waiting an 459 * acceptable period. 460 * 461 * The guarding period begins when EC_FLAGS_QUERY_PENDING is 462 * flagged, which means SCI_EVT check has just been performed. 463 * But if the current transaction is ACPI_EC_COMMAND_QUERY, the 464 * guarding should have already been performed (via 465 * EC_FLAGS_QUERY_GUARDING) and should not be applied so that the 466 * ACPI_EC_COMMAND_QUERY transaction can be transitioned into 467 * ACPI_EC_COMMAND_POLL state immediately. 468 */ 469 if (ec_event_clearing == ACPI_EC_EVT_TIMING_STATUS || 470 ec_event_clearing == ACPI_EC_EVT_TIMING_QUERY || 471 !test_bit(EC_FLAGS_QUERY_PENDING, &ec->flags) || 472 (ec->curr && ec->curr->command == ACPI_EC_COMMAND_QUERY)) 473 guarded = false; 474 spin_unlock_irqrestore(&ec->lock, flags); 475 return guarded; 476 } 477 478 static int ec_transaction_polled(struct acpi_ec *ec) 479 { 480 unsigned long flags; 481 int ret = 0; 482 483 spin_lock_irqsave(&ec->lock, flags); 484 if (ec->curr && (ec->curr->flags & ACPI_EC_COMMAND_POLL)) 485 ret = 1; 486 spin_unlock_irqrestore(&ec->lock, flags); 487 return ret; 488 } 489 490 static int ec_transaction_completed(struct acpi_ec *ec) 491 { 492 unsigned long flags; 493 int ret = 0; 494 495 spin_lock_irqsave(&ec->lock, flags); 496 if (ec->curr && (ec->curr->flags & ACPI_EC_COMMAND_COMPLETE)) 497 ret = 1; 498 spin_unlock_irqrestore(&ec->lock, flags); 499 return ret; 500 } 501 502 static inline void ec_transaction_transition(struct acpi_ec *ec, unsigned long flag) 503 { 504 ec->curr->flags |= flag; 505 if (ec->curr->command == ACPI_EC_COMMAND_QUERY) { 506 if (ec_event_clearing == ACPI_EC_EVT_TIMING_STATUS && 507 flag == ACPI_EC_COMMAND_POLL) 508 acpi_ec_complete_query(ec); 509 if (ec_event_clearing == ACPI_EC_EVT_TIMING_QUERY && 510 flag == ACPI_EC_COMMAND_COMPLETE) 511 acpi_ec_complete_query(ec); 512 if (ec_event_clearing == ACPI_EC_EVT_TIMING_EVENT && 513 flag == ACPI_EC_COMMAND_COMPLETE) 514 set_bit(EC_FLAGS_QUERY_GUARDING, &ec->flags); 515 } 516 } 517 518 static void advance_transaction(struct acpi_ec *ec) 519 { 520 struct transaction *t; 521 u8 status; 522 bool wakeup = false; 523 524 ec_dbg_stm("%s (%d)", in_interrupt() ? "IRQ" : "TASK", 525 smp_processor_id()); 526 /* 527 * By always clearing STS before handling all indications, we can 528 * ensure a hardware STS 0->1 change after this clearing can always 529 * trigger a GPE interrupt. 530 */ 531 acpi_ec_clear_gpe(ec); 532 status = acpi_ec_read_status(ec); 533 t = ec->curr; 534 /* 535 * Another IRQ or a guarded polling mode advancement is detected, 536 * the next QR_EC submission is then allowed. 537 */ 538 if (!t || !(t->flags & ACPI_EC_COMMAND_POLL)) { 539 if (ec_event_clearing == ACPI_EC_EVT_TIMING_EVENT && 540 (!ec->nr_pending_queries || 541 test_bit(EC_FLAGS_QUERY_GUARDING, &ec->flags))) { 542 clear_bit(EC_FLAGS_QUERY_GUARDING, &ec->flags); 543 acpi_ec_complete_query(ec); 544 } 545 } 546 if (!t) 547 goto err; 548 if (t->flags & ACPI_EC_COMMAND_POLL) { 549 if (t->wlen > t->wi) { 550 if ((status & ACPI_EC_FLAG_IBF) == 0) 551 acpi_ec_write_data(ec, t->wdata[t->wi++]); 552 else 553 goto err; 554 } else if (t->rlen > t->ri) { 555 if ((status & ACPI_EC_FLAG_OBF) == 1) { 556 t->rdata[t->ri++] = acpi_ec_read_data(ec); 557 if (t->rlen == t->ri) { 558 ec_transaction_transition(ec, ACPI_EC_COMMAND_COMPLETE); 559 if (t->command == ACPI_EC_COMMAND_QUERY) 560 ec_dbg_evt("Command(%s) completed by hardware", 561 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY)); 562 wakeup = true; 563 } 564 } else 565 goto err; 566 } else if (t->wlen == t->wi && 567 (status & ACPI_EC_FLAG_IBF) == 0) { 568 ec_transaction_transition(ec, ACPI_EC_COMMAND_COMPLETE); 569 wakeup = true; 570 } 571 goto out; 572 } else { 573 if (EC_FLAGS_QUERY_HANDSHAKE && 574 !(status & ACPI_EC_FLAG_SCI) && 575 (t->command == ACPI_EC_COMMAND_QUERY)) { 576 ec_transaction_transition(ec, ACPI_EC_COMMAND_POLL); 577 t->rdata[t->ri++] = 0x00; 578 ec_transaction_transition(ec, ACPI_EC_COMMAND_COMPLETE); 579 ec_dbg_evt("Command(%s) completed by software", 580 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY)); 581 wakeup = true; 582 } else if ((status & ACPI_EC_FLAG_IBF) == 0) { 583 acpi_ec_write_cmd(ec, t->command); 584 ec_transaction_transition(ec, ACPI_EC_COMMAND_POLL); 585 } else 586 goto err; 587 goto out; 588 } 589 err: 590 /* 591 * If SCI bit is set, then don't think it's a false IRQ 592 * otherwise will take a not handled IRQ as a false one. 593 */ 594 if (!(status & ACPI_EC_FLAG_SCI)) { 595 if (in_interrupt() && t) { 596 if (t->irq_count < ec_storm_threshold) 597 ++t->irq_count; 598 /* Allow triggering on 0 threshold */ 599 if (t->irq_count == ec_storm_threshold) 600 acpi_ec_set_storm(ec, EC_FLAGS_COMMAND_STORM); 601 } 602 } 603 out: 604 if (status & ACPI_EC_FLAG_SCI) 605 acpi_ec_submit_query(ec); 606 if (wakeup && in_interrupt()) 607 wake_up(&ec->wait); 608 } 609 610 static void start_transaction(struct acpi_ec *ec) 611 { 612 ec->curr->irq_count = ec->curr->wi = ec->curr->ri = 0; 613 ec->curr->flags = 0; 614 } 615 616 static int ec_guard(struct acpi_ec *ec) 617 { 618 unsigned long guard = usecs_to_jiffies(ec_polling_guard); 619 unsigned long timeout = ec->timestamp + guard; 620 621 /* Ensure guarding period before polling EC status */ 622 do { 623 if (ec_busy_polling) { 624 /* Perform busy polling */ 625 if (ec_transaction_completed(ec)) 626 return 0; 627 udelay(jiffies_to_usecs(guard)); 628 } else { 629 /* 630 * Perform wait polling 631 * 1. Wait the transaction to be completed by the 632 * GPE handler after the transaction enters 633 * ACPI_EC_COMMAND_POLL state. 634 * 2. A special guarding logic is also required 635 * for event clearing mode "event" before the 636 * transaction enters ACPI_EC_COMMAND_POLL 637 * state. 638 */ 639 if (!ec_transaction_polled(ec) && 640 !acpi_ec_guard_event(ec)) 641 break; 642 if (wait_event_timeout(ec->wait, 643 ec_transaction_completed(ec), 644 guard)) 645 return 0; 646 } 647 } while (time_before(jiffies, timeout)); 648 return -ETIME; 649 } 650 651 static int ec_poll(struct acpi_ec *ec) 652 { 653 unsigned long flags; 654 int repeat = 5; /* number of command restarts */ 655 656 while (repeat--) { 657 unsigned long delay = jiffies + 658 msecs_to_jiffies(ec_delay); 659 do { 660 if (!ec_guard(ec)) 661 return 0; 662 spin_lock_irqsave(&ec->lock, flags); 663 advance_transaction(ec); 664 spin_unlock_irqrestore(&ec->lock, flags); 665 } while (time_before(jiffies, delay)); 666 pr_debug("controller reset, restart transaction\n"); 667 spin_lock_irqsave(&ec->lock, flags); 668 start_transaction(ec); 669 spin_unlock_irqrestore(&ec->lock, flags); 670 } 671 return -ETIME; 672 } 673 674 static int acpi_ec_transaction_unlocked(struct acpi_ec *ec, 675 struct transaction *t) 676 { 677 unsigned long tmp; 678 int ret = 0; 679 680 /* start transaction */ 681 spin_lock_irqsave(&ec->lock, tmp); 682 /* Enable GPE for command processing (IBF=0/OBF=1) */ 683 if (!acpi_ec_submit_flushable_request(ec)) { 684 ret = -EINVAL; 685 goto unlock; 686 } 687 ec_dbg_ref(ec, "Increase command"); 688 /* following two actions should be kept atomic */ 689 ec->curr = t; 690 ec_dbg_req("Command(%s) started", acpi_ec_cmd_string(t->command)); 691 start_transaction(ec); 692 spin_unlock_irqrestore(&ec->lock, tmp); 693 694 ret = ec_poll(ec); 695 696 spin_lock_irqsave(&ec->lock, tmp); 697 if (t->irq_count == ec_storm_threshold) 698 acpi_ec_clear_storm(ec, EC_FLAGS_COMMAND_STORM); 699 ec_dbg_req("Command(%s) stopped", acpi_ec_cmd_string(t->command)); 700 ec->curr = NULL; 701 /* Disable GPE for command processing (IBF=0/OBF=1) */ 702 acpi_ec_complete_request(ec); 703 ec_dbg_ref(ec, "Decrease command"); 704 unlock: 705 spin_unlock_irqrestore(&ec->lock, tmp); 706 return ret; 707 } 708 709 static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t) 710 { 711 int status; 712 u32 glk; 713 714 if (!ec || (!t) || (t->wlen && !t->wdata) || (t->rlen && !t->rdata)) 715 return -EINVAL; 716 if (t->rdata) 717 memset(t->rdata, 0, t->rlen); 718 719 mutex_lock(&ec->mutex); 720 if (ec->global_lock) { 721 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk); 722 if (ACPI_FAILURE(status)) { 723 status = -ENODEV; 724 goto unlock; 725 } 726 } 727 728 status = acpi_ec_transaction_unlocked(ec, t); 729 730 if (ec->global_lock) 731 acpi_release_global_lock(glk); 732 unlock: 733 mutex_unlock(&ec->mutex); 734 return status; 735 } 736 737 static int acpi_ec_burst_enable(struct acpi_ec *ec) 738 { 739 u8 d; 740 struct transaction t = {.command = ACPI_EC_BURST_ENABLE, 741 .wdata = NULL, .rdata = &d, 742 .wlen = 0, .rlen = 1}; 743 744 return acpi_ec_transaction(ec, &t); 745 } 746 747 static int acpi_ec_burst_disable(struct acpi_ec *ec) 748 { 749 struct transaction t = {.command = ACPI_EC_BURST_DISABLE, 750 .wdata = NULL, .rdata = NULL, 751 .wlen = 0, .rlen = 0}; 752 753 return (acpi_ec_read_status(ec) & ACPI_EC_FLAG_BURST) ? 754 acpi_ec_transaction(ec, &t) : 0; 755 } 756 757 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 *data) 758 { 759 int result; 760 u8 d; 761 struct transaction t = {.command = ACPI_EC_COMMAND_READ, 762 .wdata = &address, .rdata = &d, 763 .wlen = 1, .rlen = 1}; 764 765 result = acpi_ec_transaction(ec, &t); 766 *data = d; 767 return result; 768 } 769 770 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data) 771 { 772 u8 wdata[2] = { address, data }; 773 struct transaction t = {.command = ACPI_EC_COMMAND_WRITE, 774 .wdata = wdata, .rdata = NULL, 775 .wlen = 2, .rlen = 0}; 776 777 return acpi_ec_transaction(ec, &t); 778 } 779 780 int ec_read(u8 addr, u8 *val) 781 { 782 int err; 783 u8 temp_data; 784 785 if (!first_ec) 786 return -ENODEV; 787 788 err = acpi_ec_read(first_ec, addr, &temp_data); 789 790 if (!err) { 791 *val = temp_data; 792 return 0; 793 } 794 return err; 795 } 796 EXPORT_SYMBOL(ec_read); 797 798 int ec_write(u8 addr, u8 val) 799 { 800 int err; 801 802 if (!first_ec) 803 return -ENODEV; 804 805 err = acpi_ec_write(first_ec, addr, val); 806 807 return err; 808 } 809 EXPORT_SYMBOL(ec_write); 810 811 int ec_transaction(u8 command, 812 const u8 *wdata, unsigned wdata_len, 813 u8 *rdata, unsigned rdata_len) 814 { 815 struct transaction t = {.command = command, 816 .wdata = wdata, .rdata = rdata, 817 .wlen = wdata_len, .rlen = rdata_len}; 818 819 if (!first_ec) 820 return -ENODEV; 821 822 return acpi_ec_transaction(first_ec, &t); 823 } 824 EXPORT_SYMBOL(ec_transaction); 825 826 /* Get the handle to the EC device */ 827 acpi_handle ec_get_handle(void) 828 { 829 if (!first_ec) 830 return NULL; 831 return first_ec->handle; 832 } 833 EXPORT_SYMBOL(ec_get_handle); 834 835 /* 836 * Process _Q events that might have accumulated in the EC. 837 * Run with locked ec mutex. 838 */ 839 static void acpi_ec_clear(struct acpi_ec *ec) 840 { 841 int i, status; 842 u8 value = 0; 843 844 for (i = 0; i < ACPI_EC_CLEAR_MAX; i++) { 845 status = acpi_ec_query(ec, &value); 846 if (status || !value) 847 break; 848 } 849 850 if (unlikely(i == ACPI_EC_CLEAR_MAX)) 851 pr_warn("Warning: Maximum of %d stale EC events cleared\n", i); 852 else 853 pr_info("%d stale EC events cleared\n", i); 854 } 855 856 static void acpi_ec_start(struct acpi_ec *ec, bool resuming) 857 { 858 unsigned long flags; 859 860 spin_lock_irqsave(&ec->lock, flags); 861 if (!test_and_set_bit(EC_FLAGS_STARTED, &ec->flags)) { 862 ec_dbg_drv("Starting EC"); 863 /* Enable GPE for event processing (SCI_EVT=1) */ 864 if (!resuming) { 865 acpi_ec_submit_request(ec); 866 ec_dbg_ref(ec, "Increase driver"); 867 } 868 ec_log_drv("EC started"); 869 } 870 spin_unlock_irqrestore(&ec->lock, flags); 871 } 872 873 static bool acpi_ec_stopped(struct acpi_ec *ec) 874 { 875 unsigned long flags; 876 bool flushed; 877 878 spin_lock_irqsave(&ec->lock, flags); 879 flushed = acpi_ec_flushed(ec); 880 spin_unlock_irqrestore(&ec->lock, flags); 881 return flushed; 882 } 883 884 static void acpi_ec_stop(struct acpi_ec *ec, bool suspending) 885 { 886 unsigned long flags; 887 888 spin_lock_irqsave(&ec->lock, flags); 889 if (acpi_ec_started(ec)) { 890 ec_dbg_drv("Stopping EC"); 891 set_bit(EC_FLAGS_STOPPED, &ec->flags); 892 spin_unlock_irqrestore(&ec->lock, flags); 893 wait_event(ec->wait, acpi_ec_stopped(ec)); 894 spin_lock_irqsave(&ec->lock, flags); 895 /* Disable GPE for event processing (SCI_EVT=1) */ 896 if (!suspending) { 897 acpi_ec_complete_request(ec); 898 ec_dbg_ref(ec, "Decrease driver"); 899 } 900 clear_bit(EC_FLAGS_STARTED, &ec->flags); 901 clear_bit(EC_FLAGS_STOPPED, &ec->flags); 902 ec_log_drv("EC stopped"); 903 } 904 spin_unlock_irqrestore(&ec->lock, flags); 905 } 906 907 void acpi_ec_block_transactions(void) 908 { 909 struct acpi_ec *ec = first_ec; 910 911 if (!ec) 912 return; 913 914 mutex_lock(&ec->mutex); 915 /* Prevent transactions from being carried out */ 916 acpi_ec_stop(ec, true); 917 mutex_unlock(&ec->mutex); 918 } 919 920 void acpi_ec_unblock_transactions(void) 921 { 922 struct acpi_ec *ec = first_ec; 923 924 if (!ec) 925 return; 926 927 /* Allow transactions to be carried out again */ 928 acpi_ec_start(ec, true); 929 930 if (EC_FLAGS_CLEAR_ON_RESUME) 931 acpi_ec_clear(ec); 932 } 933 934 void acpi_ec_unblock_transactions_early(void) 935 { 936 /* 937 * Allow transactions to happen again (this function is called from 938 * atomic context during wakeup, so we don't need to acquire the mutex). 939 */ 940 if (first_ec) 941 acpi_ec_start(first_ec, true); 942 } 943 944 /* -------------------------------------------------------------------------- 945 Event Management 946 -------------------------------------------------------------------------- */ 947 static struct acpi_ec_query_handler * 948 acpi_ec_get_query_handler(struct acpi_ec_query_handler *handler) 949 { 950 if (handler) 951 kref_get(&handler->kref); 952 return handler; 953 } 954 955 static struct acpi_ec_query_handler * 956 acpi_ec_get_query_handler_by_value(struct acpi_ec *ec, u8 value) 957 { 958 struct acpi_ec_query_handler *handler; 959 bool found = false; 960 961 mutex_lock(&ec->mutex); 962 list_for_each_entry(handler, &ec->list, node) { 963 if (value == handler->query_bit) { 964 found = true; 965 break; 966 } 967 } 968 mutex_unlock(&ec->mutex); 969 return found ? acpi_ec_get_query_handler(handler) : NULL; 970 } 971 972 static void acpi_ec_query_handler_release(struct kref *kref) 973 { 974 struct acpi_ec_query_handler *handler = 975 container_of(kref, struct acpi_ec_query_handler, kref); 976 977 kfree(handler); 978 } 979 980 static void acpi_ec_put_query_handler(struct acpi_ec_query_handler *handler) 981 { 982 kref_put(&handler->kref, acpi_ec_query_handler_release); 983 } 984 985 int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit, 986 acpi_handle handle, acpi_ec_query_func func, 987 void *data) 988 { 989 struct acpi_ec_query_handler *handler = 990 kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL); 991 992 if (!handler) 993 return -ENOMEM; 994 995 handler->query_bit = query_bit; 996 handler->handle = handle; 997 handler->func = func; 998 handler->data = data; 999 mutex_lock(&ec->mutex); 1000 kref_init(&handler->kref); 1001 list_add(&handler->node, &ec->list); 1002 mutex_unlock(&ec->mutex); 1003 return 0; 1004 } 1005 EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler); 1006 1007 static void acpi_ec_remove_query_handlers(struct acpi_ec *ec, 1008 bool remove_all, u8 query_bit) 1009 { 1010 struct acpi_ec_query_handler *handler, *tmp; 1011 LIST_HEAD(free_list); 1012 1013 mutex_lock(&ec->mutex); 1014 list_for_each_entry_safe(handler, tmp, &ec->list, node) { 1015 if (remove_all || query_bit == handler->query_bit) { 1016 list_del_init(&handler->node); 1017 list_add(&handler->node, &free_list); 1018 } 1019 } 1020 mutex_unlock(&ec->mutex); 1021 list_for_each_entry_safe(handler, tmp, &free_list, node) 1022 acpi_ec_put_query_handler(handler); 1023 } 1024 1025 void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit) 1026 { 1027 acpi_ec_remove_query_handlers(ec, false, query_bit); 1028 } 1029 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler); 1030 1031 static struct acpi_ec_query *acpi_ec_create_query(u8 *pval) 1032 { 1033 struct acpi_ec_query *q; 1034 struct transaction *t; 1035 1036 q = kzalloc(sizeof (struct acpi_ec_query), GFP_KERNEL); 1037 if (!q) 1038 return NULL; 1039 INIT_WORK(&q->work, acpi_ec_event_processor); 1040 t = &q->transaction; 1041 t->command = ACPI_EC_COMMAND_QUERY; 1042 t->rdata = pval; 1043 t->rlen = 1; 1044 return q; 1045 } 1046 1047 static void acpi_ec_delete_query(struct acpi_ec_query *q) 1048 { 1049 if (q) { 1050 if (q->handler) 1051 acpi_ec_put_query_handler(q->handler); 1052 kfree(q); 1053 } 1054 } 1055 1056 static void acpi_ec_event_processor(struct work_struct *work) 1057 { 1058 struct acpi_ec_query *q = container_of(work, struct acpi_ec_query, work); 1059 struct acpi_ec_query_handler *handler = q->handler; 1060 1061 ec_dbg_evt("Query(0x%02x) started", handler->query_bit); 1062 if (handler->func) 1063 handler->func(handler->data); 1064 else if (handler->handle) 1065 acpi_evaluate_object(handler->handle, NULL, NULL, NULL); 1066 ec_dbg_evt("Query(0x%02x) stopped", handler->query_bit); 1067 acpi_ec_delete_query(q); 1068 } 1069 1070 static int acpi_ec_query(struct acpi_ec *ec, u8 *data) 1071 { 1072 u8 value = 0; 1073 int result; 1074 struct acpi_ec_query *q; 1075 1076 q = acpi_ec_create_query(&value); 1077 if (!q) 1078 return -ENOMEM; 1079 1080 /* 1081 * Query the EC to find out which _Qxx method we need to evaluate. 1082 * Note that successful completion of the query causes the ACPI_EC_SCI 1083 * bit to be cleared (and thus clearing the interrupt source). 1084 */ 1085 result = acpi_ec_transaction(ec, &q->transaction); 1086 if (!value) 1087 result = -ENODATA; 1088 if (result) 1089 goto err_exit; 1090 1091 q->handler = acpi_ec_get_query_handler_by_value(ec, value); 1092 if (!q->handler) { 1093 result = -ENODATA; 1094 goto err_exit; 1095 } 1096 1097 /* 1098 * It is reported that _Qxx are evaluated in a parallel way on 1099 * Windows: 1100 * https://bugzilla.kernel.org/show_bug.cgi?id=94411 1101 * 1102 * Put this log entry before schedule_work() in order to make 1103 * it appearing before any other log entries occurred during the 1104 * work queue execution. 1105 */ 1106 ec_dbg_evt("Query(0x%02x) scheduled", value); 1107 if (!queue_work(ec_query_wq, &q->work)) { 1108 ec_dbg_evt("Query(0x%02x) overlapped", value); 1109 result = -EBUSY; 1110 } 1111 1112 err_exit: 1113 if (result) 1114 acpi_ec_delete_query(q); 1115 if (data) 1116 *data = value; 1117 return result; 1118 } 1119 1120 static void acpi_ec_check_event(struct acpi_ec *ec) 1121 { 1122 unsigned long flags; 1123 1124 if (ec_event_clearing == ACPI_EC_EVT_TIMING_EVENT) { 1125 if (ec_guard(ec)) { 1126 spin_lock_irqsave(&ec->lock, flags); 1127 /* 1128 * Take care of the SCI_EVT unless no one else is 1129 * taking care of it. 1130 */ 1131 if (!ec->curr) 1132 advance_transaction(ec); 1133 spin_unlock_irqrestore(&ec->lock, flags); 1134 } 1135 } 1136 } 1137 1138 static void acpi_ec_event_handler(struct work_struct *work) 1139 { 1140 unsigned long flags; 1141 struct acpi_ec *ec = container_of(work, struct acpi_ec, work); 1142 1143 ec_dbg_evt("Event started"); 1144 1145 spin_lock_irqsave(&ec->lock, flags); 1146 while (ec->nr_pending_queries) { 1147 spin_unlock_irqrestore(&ec->lock, flags); 1148 (void)acpi_ec_query(ec, NULL); 1149 spin_lock_irqsave(&ec->lock, flags); 1150 ec->nr_pending_queries--; 1151 /* 1152 * Before exit, make sure that this work item can be 1153 * scheduled again. There might be QR_EC failures, leaving 1154 * EC_FLAGS_QUERY_PENDING uncleared and preventing this work 1155 * item from being scheduled again. 1156 */ 1157 if (!ec->nr_pending_queries) { 1158 if (ec_event_clearing == ACPI_EC_EVT_TIMING_STATUS || 1159 ec_event_clearing == ACPI_EC_EVT_TIMING_QUERY) 1160 acpi_ec_complete_query(ec); 1161 } 1162 } 1163 spin_unlock_irqrestore(&ec->lock, flags); 1164 1165 ec_dbg_evt("Event stopped"); 1166 1167 acpi_ec_check_event(ec); 1168 } 1169 1170 static u32 acpi_ec_gpe_handler(acpi_handle gpe_device, 1171 u32 gpe_number, void *data) 1172 { 1173 unsigned long flags; 1174 struct acpi_ec *ec = data; 1175 1176 spin_lock_irqsave(&ec->lock, flags); 1177 advance_transaction(ec); 1178 spin_unlock_irqrestore(&ec->lock, flags); 1179 return ACPI_INTERRUPT_HANDLED; 1180 } 1181 1182 /* -------------------------------------------------------------------------- 1183 * Address Space Management 1184 * -------------------------------------------------------------------------- */ 1185 1186 static acpi_status 1187 acpi_ec_space_handler(u32 function, acpi_physical_address address, 1188 u32 bits, u64 *value64, 1189 void *handler_context, void *region_context) 1190 { 1191 struct acpi_ec *ec = handler_context; 1192 int result = 0, i, bytes = bits / 8; 1193 u8 *value = (u8 *)value64; 1194 1195 if ((address > 0xFF) || !value || !handler_context) 1196 return AE_BAD_PARAMETER; 1197 1198 if (function != ACPI_READ && function != ACPI_WRITE) 1199 return AE_BAD_PARAMETER; 1200 1201 if (ec_busy_polling || bits > 8) 1202 acpi_ec_burst_enable(ec); 1203 1204 for (i = 0; i < bytes; ++i, ++address, ++value) 1205 result = (function == ACPI_READ) ? 1206 acpi_ec_read(ec, address, value) : 1207 acpi_ec_write(ec, address, *value); 1208 1209 if (ec_busy_polling || bits > 8) 1210 acpi_ec_burst_disable(ec); 1211 1212 switch (result) { 1213 case -EINVAL: 1214 return AE_BAD_PARAMETER; 1215 case -ENODEV: 1216 return AE_NOT_FOUND; 1217 case -ETIME: 1218 return AE_TIME; 1219 default: 1220 return AE_OK; 1221 } 1222 } 1223 1224 /* -------------------------------------------------------------------------- 1225 * Driver Interface 1226 * -------------------------------------------------------------------------- */ 1227 1228 static acpi_status 1229 ec_parse_io_ports(struct acpi_resource *resource, void *context); 1230 1231 static struct acpi_ec *make_acpi_ec(void) 1232 { 1233 struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL); 1234 1235 if (!ec) 1236 return NULL; 1237 ec->flags = 1 << EC_FLAGS_QUERY_PENDING; 1238 mutex_init(&ec->mutex); 1239 init_waitqueue_head(&ec->wait); 1240 INIT_LIST_HEAD(&ec->list); 1241 spin_lock_init(&ec->lock); 1242 INIT_WORK(&ec->work, acpi_ec_event_handler); 1243 ec->timestamp = jiffies; 1244 return ec; 1245 } 1246 1247 static acpi_status 1248 acpi_ec_register_query_methods(acpi_handle handle, u32 level, 1249 void *context, void **return_value) 1250 { 1251 char node_name[5]; 1252 struct acpi_buffer buffer = { sizeof(node_name), node_name }; 1253 struct acpi_ec *ec = context; 1254 int value = 0; 1255 acpi_status status; 1256 1257 status = acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer); 1258 1259 if (ACPI_SUCCESS(status) && sscanf(node_name, "_Q%x", &value) == 1) 1260 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL); 1261 return AE_OK; 1262 } 1263 1264 static acpi_status 1265 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval) 1266 { 1267 acpi_status status; 1268 unsigned long long tmp = 0; 1269 struct acpi_ec *ec = context; 1270 1271 /* clear addr values, ec_parse_io_ports depend on it */ 1272 ec->command_addr = ec->data_addr = 0; 1273 1274 status = acpi_walk_resources(handle, METHOD_NAME__CRS, 1275 ec_parse_io_ports, ec); 1276 if (ACPI_FAILURE(status)) 1277 return status; 1278 1279 /* Get GPE bit assignment (EC events). */ 1280 /* TODO: Add support for _GPE returning a package */ 1281 status = acpi_evaluate_integer(handle, "_GPE", NULL, &tmp); 1282 if (ACPI_FAILURE(status)) 1283 return status; 1284 ec->gpe = tmp; 1285 /* Use the global lock for all EC transactions? */ 1286 tmp = 0; 1287 acpi_evaluate_integer(handle, "_GLK", NULL, &tmp); 1288 ec->global_lock = tmp; 1289 ec->handle = handle; 1290 return AE_CTRL_TERMINATE; 1291 } 1292 1293 static int ec_install_handlers(struct acpi_ec *ec) 1294 { 1295 acpi_status status; 1296 1297 acpi_ec_start(ec, false); 1298 1299 if (!test_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags)) { 1300 status = acpi_install_address_space_handler(ec->handle, 1301 ACPI_ADR_SPACE_EC, 1302 &acpi_ec_space_handler, 1303 NULL, ec); 1304 if (ACPI_FAILURE(status)) { 1305 if (status == AE_NOT_FOUND) { 1306 /* 1307 * Maybe OS fails in evaluating the _REG 1308 * object. The AE_NOT_FOUND error will be 1309 * ignored and OS * continue to initialize 1310 * EC. 1311 */ 1312 pr_err("Fail in evaluating the _REG object" 1313 " of EC device. Broken bios is suspected.\n"); 1314 } else { 1315 acpi_ec_stop(ec, false); 1316 return -ENODEV; 1317 } 1318 } 1319 set_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags); 1320 } 1321 1322 if (!test_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags)) { 1323 status = acpi_install_gpe_raw_handler(NULL, ec->gpe, 1324 ACPI_GPE_EDGE_TRIGGERED, 1325 &acpi_ec_gpe_handler, ec); 1326 /* This is not fatal as we can poll EC events */ 1327 if (ACPI_SUCCESS(status)) { 1328 set_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags); 1329 if (test_bit(EC_FLAGS_STARTED, &ec->flags) && 1330 ec->reference_count >= 1) 1331 acpi_ec_enable_gpe(ec, true); 1332 } 1333 } 1334 1335 return 0; 1336 } 1337 1338 static void ec_remove_handlers(struct acpi_ec *ec) 1339 { 1340 if (test_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags)) { 1341 if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle, 1342 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler))) 1343 pr_err("failed to remove space handler\n"); 1344 clear_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags); 1345 } 1346 1347 /* 1348 * Stops handling the EC transactions after removing the operation 1349 * region handler. This is required because _REG(DISCONNECT) 1350 * invoked during the removal can result in new EC transactions. 1351 * 1352 * Flushes the EC requests and thus disables the GPE before 1353 * removing the GPE handler. This is required by the current ACPICA 1354 * GPE core. ACPICA GPE core will automatically disable a GPE when 1355 * it is indicated but there is no way to handle it. So the drivers 1356 * must disable the GPEs prior to removing the GPE handlers. 1357 */ 1358 acpi_ec_stop(ec, false); 1359 1360 if (test_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags)) { 1361 if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe, 1362 &acpi_ec_gpe_handler))) 1363 pr_err("failed to remove gpe handler\n"); 1364 clear_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags); 1365 } 1366 } 1367 1368 static struct acpi_ec *acpi_ec_alloc(void) 1369 { 1370 struct acpi_ec *ec; 1371 1372 /* Check for boot EC */ 1373 if (boot_ec) { 1374 ec = boot_ec; 1375 boot_ec = NULL; 1376 ec_remove_handlers(ec); 1377 if (first_ec == ec) 1378 first_ec = NULL; 1379 } else { 1380 ec = make_acpi_ec(); 1381 } 1382 return ec; 1383 } 1384 1385 static int acpi_ec_add(struct acpi_device *device) 1386 { 1387 struct acpi_ec *ec = NULL; 1388 int ret; 1389 1390 strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME); 1391 strcpy(acpi_device_class(device), ACPI_EC_CLASS); 1392 1393 ec = acpi_ec_alloc(); 1394 if (!ec) 1395 return -ENOMEM; 1396 if (ec_parse_device(device->handle, 0, ec, NULL) != 1397 AE_CTRL_TERMINATE) { 1398 kfree(ec); 1399 return -EINVAL; 1400 } 1401 1402 /* Find and register all query methods */ 1403 acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1, 1404 acpi_ec_register_query_methods, NULL, ec, NULL); 1405 1406 if (!first_ec) 1407 first_ec = ec; 1408 device->driver_data = ec; 1409 1410 ret = !!request_region(ec->data_addr, 1, "EC data"); 1411 WARN(!ret, "Could not request EC data io port 0x%lx", ec->data_addr); 1412 ret = !!request_region(ec->command_addr, 1, "EC cmd"); 1413 WARN(!ret, "Could not request EC cmd io port 0x%lx", ec->command_addr); 1414 1415 pr_info("GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n", 1416 ec->gpe, ec->command_addr, ec->data_addr); 1417 1418 ret = ec_install_handlers(ec); 1419 1420 /* Reprobe devices depending on the EC */ 1421 acpi_walk_dep_device_list(ec->handle); 1422 1423 /* EC is fully operational, allow queries */ 1424 clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags); 1425 1426 /* Clear stale _Q events if hardware might require that */ 1427 if (EC_FLAGS_CLEAR_ON_RESUME) 1428 acpi_ec_clear(ec); 1429 return ret; 1430 } 1431 1432 static int acpi_ec_remove(struct acpi_device *device) 1433 { 1434 struct acpi_ec *ec; 1435 1436 if (!device) 1437 return -EINVAL; 1438 1439 ec = acpi_driver_data(device); 1440 ec_remove_handlers(ec); 1441 acpi_ec_remove_query_handlers(ec, true, 0); 1442 release_region(ec->data_addr, 1); 1443 release_region(ec->command_addr, 1); 1444 device->driver_data = NULL; 1445 if (ec == first_ec) 1446 first_ec = NULL; 1447 kfree(ec); 1448 return 0; 1449 } 1450 1451 static acpi_status 1452 ec_parse_io_ports(struct acpi_resource *resource, void *context) 1453 { 1454 struct acpi_ec *ec = context; 1455 1456 if (resource->type != ACPI_RESOURCE_TYPE_IO) 1457 return AE_OK; 1458 1459 /* 1460 * The first address region returned is the data port, and 1461 * the second address region returned is the status/command 1462 * port. 1463 */ 1464 if (ec->data_addr == 0) 1465 ec->data_addr = resource->data.io.minimum; 1466 else if (ec->command_addr == 0) 1467 ec->command_addr = resource->data.io.minimum; 1468 else 1469 return AE_CTRL_TERMINATE; 1470 1471 return AE_OK; 1472 } 1473 1474 static const struct acpi_device_id ec_device_ids[] = { 1475 {"PNP0C09", 0}, 1476 {"", 0}, 1477 }; 1478 1479 int __init acpi_ec_dsdt_probe(void) 1480 { 1481 acpi_status status; 1482 struct acpi_ec *ec; 1483 int ret; 1484 1485 ec = acpi_ec_alloc(); 1486 if (!ec) 1487 return -ENOMEM; 1488 /* 1489 * Finding EC from DSDT if there is no ECDT EC available. When this 1490 * function is invoked, ACPI tables have been fully loaded, we can 1491 * walk namespace now. 1492 */ 1493 status = acpi_get_devices(ec_device_ids[0].id, 1494 ec_parse_device, ec, NULL); 1495 if (ACPI_FAILURE(status) || !ec->handle) { 1496 ret = -ENODEV; 1497 goto error; 1498 } 1499 ret = ec_install_handlers(ec); 1500 1501 error: 1502 if (ret) 1503 kfree(ec); 1504 else 1505 first_ec = boot_ec = ec; 1506 return ret; 1507 } 1508 1509 #if 0 1510 /* 1511 * Some EC firmware variations refuses to respond QR_EC when SCI_EVT is not 1512 * set, for which case, we complete the QR_EC without issuing it to the 1513 * firmware. 1514 * https://bugzilla.kernel.org/show_bug.cgi?id=82611 1515 * https://bugzilla.kernel.org/show_bug.cgi?id=97381 1516 */ 1517 static int ec_flag_query_handshake(const struct dmi_system_id *id) 1518 { 1519 pr_debug("Detected the EC firmware requiring QR_EC issued when SCI_EVT set\n"); 1520 EC_FLAGS_QUERY_HANDSHAKE = 1; 1521 return 0; 1522 } 1523 #endif 1524 1525 /* 1526 * On some hardware it is necessary to clear events accumulated by the EC during 1527 * sleep. These ECs stop reporting GPEs until they are manually polled, if too 1528 * many events are accumulated. (e.g. Samsung Series 5/9 notebooks) 1529 * 1530 * https://bugzilla.kernel.org/show_bug.cgi?id=44161 1531 * 1532 * Ideally, the EC should also be instructed NOT to accumulate events during 1533 * sleep (which Windows seems to do somehow), but the interface to control this 1534 * behaviour is not known at this time. 1535 * 1536 * Models known to be affected are Samsung 530Uxx/535Uxx/540Uxx/550Pxx/900Xxx, 1537 * however it is very likely that other Samsung models are affected. 1538 * 1539 * On systems which don't accumulate _Q events during sleep, this extra check 1540 * should be harmless. 1541 */ 1542 static int ec_clear_on_resume(const struct dmi_system_id *id) 1543 { 1544 pr_debug("Detected system needing EC poll on resume.\n"); 1545 EC_FLAGS_CLEAR_ON_RESUME = 1; 1546 ec_event_clearing = ACPI_EC_EVT_TIMING_STATUS; 1547 return 0; 1548 } 1549 1550 /* 1551 * Some ECDTs contain wrong register addresses. 1552 * MSI MS-171F 1553 * https://bugzilla.kernel.org/show_bug.cgi?id=12461 1554 */ 1555 static int ec_correct_ecdt(const struct dmi_system_id *id) 1556 { 1557 pr_debug("Detected system needing ECDT address correction.\n"); 1558 EC_FLAGS_CORRECT_ECDT = 1; 1559 return 0; 1560 } 1561 1562 static struct dmi_system_id ec_dmi_table[] __initdata = { 1563 { 1564 ec_correct_ecdt, "MSI MS-171F", { 1565 DMI_MATCH(DMI_SYS_VENDOR, "Micro-Star"), 1566 DMI_MATCH(DMI_PRODUCT_NAME, "MS-171F"),}, NULL}, 1567 { 1568 ec_clear_on_resume, "Samsung hardware", { 1569 DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD.")}, NULL}, 1570 {}, 1571 }; 1572 1573 int __init acpi_ec_ecdt_probe(void) 1574 { 1575 int ret; 1576 acpi_status status; 1577 struct acpi_table_ecdt *ecdt_ptr; 1578 struct acpi_ec *ec; 1579 1580 ec = acpi_ec_alloc(); 1581 if (!ec) 1582 return -ENOMEM; 1583 /* 1584 * Generate a boot ec context 1585 */ 1586 dmi_check_system(ec_dmi_table); 1587 status = acpi_get_table(ACPI_SIG_ECDT, 1, 1588 (struct acpi_table_header **)&ecdt_ptr); 1589 if (ACPI_FAILURE(status)) { 1590 ret = -ENODEV; 1591 goto error; 1592 } 1593 1594 if (!ecdt_ptr->control.address || !ecdt_ptr->data.address) { 1595 /* 1596 * Asus X50GL: 1597 * https://bugzilla.kernel.org/show_bug.cgi?id=11880 1598 */ 1599 ret = -ENODEV; 1600 goto error; 1601 } 1602 1603 pr_info("EC description table is found, configuring boot EC\n"); 1604 if (EC_FLAGS_CORRECT_ECDT) { 1605 ec->command_addr = ecdt_ptr->data.address; 1606 ec->data_addr = ecdt_ptr->control.address; 1607 } else { 1608 ec->command_addr = ecdt_ptr->control.address; 1609 ec->data_addr = ecdt_ptr->data.address; 1610 } 1611 ec->gpe = ecdt_ptr->gpe; 1612 ec->handle = ACPI_ROOT_OBJECT; 1613 ret = ec_install_handlers(ec); 1614 error: 1615 if (ret) 1616 kfree(ec); 1617 else 1618 first_ec = boot_ec = ec; 1619 return ret; 1620 } 1621 1622 static int param_set_event_clearing(const char *val, struct kernel_param *kp) 1623 { 1624 int result = 0; 1625 1626 if (!strncmp(val, "status", sizeof("status") - 1)) { 1627 ec_event_clearing = ACPI_EC_EVT_TIMING_STATUS; 1628 pr_info("Assuming SCI_EVT clearing on EC_SC accesses\n"); 1629 } else if (!strncmp(val, "query", sizeof("query") - 1)) { 1630 ec_event_clearing = ACPI_EC_EVT_TIMING_QUERY; 1631 pr_info("Assuming SCI_EVT clearing on QR_EC writes\n"); 1632 } else if (!strncmp(val, "event", sizeof("event") - 1)) { 1633 ec_event_clearing = ACPI_EC_EVT_TIMING_EVENT; 1634 pr_info("Assuming SCI_EVT clearing on event reads\n"); 1635 } else 1636 result = -EINVAL; 1637 return result; 1638 } 1639 1640 static int param_get_event_clearing(char *buffer, struct kernel_param *kp) 1641 { 1642 switch (ec_event_clearing) { 1643 case ACPI_EC_EVT_TIMING_STATUS: 1644 return sprintf(buffer, "status"); 1645 case ACPI_EC_EVT_TIMING_QUERY: 1646 return sprintf(buffer, "query"); 1647 case ACPI_EC_EVT_TIMING_EVENT: 1648 return sprintf(buffer, "event"); 1649 default: 1650 return sprintf(buffer, "invalid"); 1651 } 1652 return 0; 1653 } 1654 1655 module_param_call(ec_event_clearing, param_set_event_clearing, param_get_event_clearing, 1656 NULL, 0644); 1657 MODULE_PARM_DESC(ec_event_clearing, "Assumed SCI_EVT clearing timing"); 1658 1659 static struct acpi_driver acpi_ec_driver = { 1660 .name = "ec", 1661 .class = ACPI_EC_CLASS, 1662 .ids = ec_device_ids, 1663 .ops = { 1664 .add = acpi_ec_add, 1665 .remove = acpi_ec_remove, 1666 }, 1667 }; 1668 1669 static inline int acpi_ec_query_init(void) 1670 { 1671 if (!ec_query_wq) { 1672 ec_query_wq = alloc_workqueue("kec_query", 0, 1673 ec_max_queries); 1674 if (!ec_query_wq) 1675 return -ENODEV; 1676 } 1677 return 0; 1678 } 1679 1680 static inline void acpi_ec_query_exit(void) 1681 { 1682 if (ec_query_wq) { 1683 destroy_workqueue(ec_query_wq); 1684 ec_query_wq = NULL; 1685 } 1686 } 1687 1688 int __init acpi_ec_init(void) 1689 { 1690 int result; 1691 1692 /* register workqueue for _Qxx evaluations */ 1693 result = acpi_ec_query_init(); 1694 if (result) 1695 goto err_exit; 1696 /* Now register the driver for the EC */ 1697 result = acpi_bus_register_driver(&acpi_ec_driver); 1698 if (result) 1699 goto err_exit; 1700 1701 err_exit: 1702 if (result) 1703 acpi_ec_query_exit(); 1704 return result; 1705 } 1706 1707 /* EC driver currently not unloadable */ 1708 #if 0 1709 static void __exit acpi_ec_exit(void) 1710 { 1711 1712 acpi_bus_unregister_driver(&acpi_ec_driver); 1713 acpi_ec_query_exit(); 1714 } 1715 #endif /* 0 */ 1716