2 * ec.c - ACPI Embedded Controller Driver (v3)
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>
13 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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.
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.
25 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
28 /* Uncomment next line to get verbose printout */
30 #define pr_fmt(fmt) "ACPI: EC: " fmt
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>
47 #define ACPI_EC_CLASS "embedded_controller"
48 #define ACPI_EC_DEVICE_NAME "Embedded Controller"
49 #define ACPI_EC_FILE_INFO "info"
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 */
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
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
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.
86 #define ACPI_EC_EVT_TIMING_STATUS 0x00
87 #define ACPI_EC_EVT_TIMING_QUERY 0x01
88 #define ACPI_EC_EVT_TIMING_EVENT 0x02
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,
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 */
107 EC_FLAGS_QUERY_ENABLED, /* Query is enabled */
108 EC_FLAGS_QUERY_PENDING, /* Query is pending */
109 EC_FLAGS_QUERY_GUARDING, /* Guard for SCI_EVT check */
110 EC_FLAGS_GPE_HANDLER_INSTALLED, /* GPE handler installed */
111 EC_FLAGS_EC_HANDLER_INSTALLED, /* OpReg handler installed */
112 EC_FLAGS_EVT_HANDLER_INSTALLED, /* _Qxx handlers installed */
113 EC_FLAGS_STARTED, /* Driver is started */
114 EC_FLAGS_STOPPED, /* Driver is stopped */
115 EC_FLAGS_GPE_MASKED, /* GPE masked */
118 #define ACPI_EC_COMMAND_POLL 0x01 /* Available for command byte */
119 #define ACPI_EC_COMMAND_COMPLETE 0x02 /* Completed last byte */
121 /* ec.c is compiled in acpi namespace so this shows up as acpi.ec_delay param */
122 static unsigned int ec_delay __read_mostly = ACPI_EC_DELAY;
123 module_param(ec_delay, uint, 0644);
124 MODULE_PARM_DESC(ec_delay, "Timeout(ms) waited until an EC command completes");
126 static unsigned int ec_max_queries __read_mostly = ACPI_EC_MAX_QUERIES;
127 module_param(ec_max_queries, uint, 0644);
128 MODULE_PARM_DESC(ec_max_queries, "Maximum parallel _Qxx evaluations");
130 static bool ec_busy_polling __read_mostly;
131 module_param(ec_busy_polling, bool, 0644);
132 MODULE_PARM_DESC(ec_busy_polling, "Use busy polling to advance EC transaction");
134 static unsigned int ec_polling_guard __read_mostly = ACPI_EC_UDELAY_POLL;
135 module_param(ec_polling_guard, uint, 0644);
136 MODULE_PARM_DESC(ec_polling_guard, "Guard time(us) between EC accesses in polling modes");
138 static unsigned int ec_event_clearing __read_mostly = ACPI_EC_EVT_TIMING_QUERY;
141 * If the number of false interrupts per one transaction exceeds
142 * this threshold, will think there is a GPE storm happened and
143 * will disable the GPE for normal transaction.
145 static unsigned int ec_storm_threshold __read_mostly = 8;
146 module_param(ec_storm_threshold, uint, 0644);
147 MODULE_PARM_DESC(ec_storm_threshold, "Maxim false GPE numbers not considered as GPE storm");
149 static bool ec_freeze_events __read_mostly = false;
150 module_param(ec_freeze_events, bool, 0644);
151 MODULE_PARM_DESC(ec_freeze_events, "Disabling event handling during suspend/resume");
153 static bool ec_no_wakeup __read_mostly;
154 module_param(ec_no_wakeup, bool, 0644);
155 MODULE_PARM_DESC(ec_no_wakeup, "Do not wake up from suspend-to-idle");
157 struct acpi_ec_query_handler {
158 struct list_head node;
159 acpi_ec_query_func func;
169 unsigned short irq_count;
178 struct acpi_ec_query {
179 struct transaction transaction;
180 struct work_struct work;
181 struct acpi_ec_query_handler *handler;
184 static int acpi_ec_query(struct acpi_ec *ec, u8 *data);
185 static void advance_transaction(struct acpi_ec *ec);
186 static void acpi_ec_event_handler(struct work_struct *work);
187 static void acpi_ec_event_processor(struct work_struct *work);
189 struct acpi_ec *boot_ec, *first_ec;
190 EXPORT_SYMBOL(first_ec);
191 static bool boot_ec_is_ecdt = false;
192 static struct workqueue_struct *ec_query_wq;
194 static int EC_FLAGS_QUERY_HANDSHAKE; /* Needs QR_EC issued when SCI_EVT set */
195 static int EC_FLAGS_CORRECT_ECDT; /* Needs ECDT port address correction */
196 static int EC_FLAGS_IGNORE_DSDT_GPE; /* Needs ECDT GPE as correction setting */
197 static int EC_FLAGS_CLEAR_ON_RESUME; /* Needs acpi_ec_clear() on boot/resume */
199 /* --------------------------------------------------------------------------
201 * -------------------------------------------------------------------------- */
204 * Splitters used by the developers to track the boundary of the EC
205 * handling processes.
208 #define EC_DBG_SEP " "
209 #define EC_DBG_DRV "+++++"
210 #define EC_DBG_STM "====="
211 #define EC_DBG_REQ "*****"
212 #define EC_DBG_EVT "#####"
214 #define EC_DBG_SEP ""
221 #define ec_log_raw(fmt, ...) \
222 pr_info(fmt "\n", ##__VA_ARGS__)
223 #define ec_dbg_raw(fmt, ...) \
224 pr_debug(fmt "\n", ##__VA_ARGS__)
225 #define ec_log(filter, fmt, ...) \
226 ec_log_raw(filter EC_DBG_SEP fmt EC_DBG_SEP filter, ##__VA_ARGS__)
227 #define ec_dbg(filter, fmt, ...) \
228 ec_dbg_raw(filter EC_DBG_SEP fmt EC_DBG_SEP filter, ##__VA_ARGS__)
230 #define ec_log_drv(fmt, ...) \
231 ec_log(EC_DBG_DRV, fmt, ##__VA_ARGS__)
232 #define ec_dbg_drv(fmt, ...) \
233 ec_dbg(EC_DBG_DRV, fmt, ##__VA_ARGS__)
234 #define ec_dbg_stm(fmt, ...) \
235 ec_dbg(EC_DBG_STM, fmt, ##__VA_ARGS__)
236 #define ec_dbg_req(fmt, ...) \
237 ec_dbg(EC_DBG_REQ, fmt, ##__VA_ARGS__)
238 #define ec_dbg_evt(fmt, ...) \
239 ec_dbg(EC_DBG_EVT, fmt, ##__VA_ARGS__)
240 #define ec_dbg_ref(ec, fmt, ...) \
241 ec_dbg_raw("%lu: " fmt, ec->reference_count, ## __VA_ARGS__)
243 /* --------------------------------------------------------------------------
245 * -------------------------------------------------------------------------- */
247 static bool acpi_ec_started(struct acpi_ec *ec)
249 return test_bit(EC_FLAGS_STARTED, &ec->flags) &&
250 !test_bit(EC_FLAGS_STOPPED, &ec->flags);
253 static bool acpi_ec_event_enabled(struct acpi_ec *ec)
256 * There is an OSPM early stage logic. During the early stages
257 * (boot/resume), OSPMs shouldn't enable the event handling, only
258 * the EC transactions are allowed to be performed.
260 if (!test_bit(EC_FLAGS_QUERY_ENABLED, &ec->flags))
263 * However, disabling the event handling is experimental for late
264 * stage (suspend), and is controlled by the boot parameter of
265 * "ec_freeze_events":
266 * 1. true: The EC event handling is disabled before entering
268 * 2. false: The EC event handling is automatically disabled as
269 * soon as the EC driver is stopped.
271 if (ec_freeze_events)
272 return acpi_ec_started(ec);
274 return test_bit(EC_FLAGS_STARTED, &ec->flags);
277 static bool acpi_ec_flushed(struct acpi_ec *ec)
279 return ec->reference_count == 1;
282 /* --------------------------------------------------------------------------
284 * -------------------------------------------------------------------------- */
286 static inline u8 acpi_ec_read_status(struct acpi_ec *ec)
288 u8 x = inb(ec->command_addr);
290 ec_dbg_raw("EC_SC(R) = 0x%2.2x "
291 "SCI_EVT=%d BURST=%d CMD=%d IBF=%d OBF=%d",
293 !!(x & ACPI_EC_FLAG_SCI),
294 !!(x & ACPI_EC_FLAG_BURST),
295 !!(x & ACPI_EC_FLAG_CMD),
296 !!(x & ACPI_EC_FLAG_IBF),
297 !!(x & ACPI_EC_FLAG_OBF));
301 static inline u8 acpi_ec_read_data(struct acpi_ec *ec)
303 u8 x = inb(ec->data_addr);
305 ec->timestamp = jiffies;
306 ec_dbg_raw("EC_DATA(R) = 0x%2.2x", x);
310 static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command)
312 ec_dbg_raw("EC_SC(W) = 0x%2.2x", command);
313 outb(command, ec->command_addr);
314 ec->timestamp = jiffies;
317 static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data)
319 ec_dbg_raw("EC_DATA(W) = 0x%2.2x", data);
320 outb(data, ec->data_addr);
321 ec->timestamp = jiffies;
324 #if defined(DEBUG) || defined(CONFIG_DYNAMIC_DEBUG)
325 static const char *acpi_ec_cmd_string(u8 cmd)
342 #define acpi_ec_cmd_string(cmd) "UNDEF"
345 /* --------------------------------------------------------------------------
347 * -------------------------------------------------------------------------- */
349 static inline bool acpi_ec_is_gpe_raised(struct acpi_ec *ec)
351 acpi_event_status gpe_status = 0;
353 (void)acpi_get_gpe_status(NULL, ec->gpe, &gpe_status);
354 return (gpe_status & ACPI_EVENT_FLAG_STATUS_SET) ? true : false;
357 static inline void acpi_ec_enable_gpe(struct acpi_ec *ec, bool open)
360 acpi_enable_gpe(NULL, ec->gpe);
362 BUG_ON(ec->reference_count < 1);
363 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_ENABLE);
365 if (acpi_ec_is_gpe_raised(ec)) {
367 * On some platforms, EN=1 writes cannot trigger GPE. So
368 * software need to manually trigger a pseudo GPE event on
371 ec_dbg_raw("Polling quirk");
372 advance_transaction(ec);
376 static inline void acpi_ec_disable_gpe(struct acpi_ec *ec, bool close)
379 acpi_disable_gpe(NULL, ec->gpe);
381 BUG_ON(ec->reference_count < 1);
382 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_DISABLE);
386 static inline void acpi_ec_clear_gpe(struct acpi_ec *ec)
389 * GPE STS is a W1C register, which means:
390 * 1. Software can clear it without worrying about clearing other
391 * GPEs' STS bits when the hardware sets them in parallel.
392 * 2. As long as software can ensure only clearing it when it is
393 * set, hardware won't set it in parallel.
394 * So software can clear GPE in any contexts.
395 * Warning: do not move the check into advance_transaction() as the
396 * EC commands will be sent without GPE raised.
398 if (!acpi_ec_is_gpe_raised(ec))
400 acpi_clear_gpe(NULL, ec->gpe);
403 /* --------------------------------------------------------------------------
404 * Transaction Management
405 * -------------------------------------------------------------------------- */
407 static void acpi_ec_submit_request(struct acpi_ec *ec)
409 ec->reference_count++;
410 if (test_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags) &&
411 ec->reference_count == 1)
412 acpi_ec_enable_gpe(ec, true);
415 static void acpi_ec_complete_request(struct acpi_ec *ec)
417 bool flushed = false;
419 ec->reference_count--;
420 if (test_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags) &&
421 ec->reference_count == 0)
422 acpi_ec_disable_gpe(ec, true);
423 flushed = acpi_ec_flushed(ec);
428 static void acpi_ec_mask_gpe(struct acpi_ec *ec)
430 if (!test_bit(EC_FLAGS_GPE_MASKED, &ec->flags)) {
431 acpi_ec_disable_gpe(ec, false);
432 ec_dbg_drv("Polling enabled");
433 set_bit(EC_FLAGS_GPE_MASKED, &ec->flags);
437 static void acpi_ec_unmask_gpe(struct acpi_ec *ec)
439 if (test_bit(EC_FLAGS_GPE_MASKED, &ec->flags)) {
440 clear_bit(EC_FLAGS_GPE_MASKED, &ec->flags);
441 acpi_ec_enable_gpe(ec, false);
442 ec_dbg_drv("Polling disabled");
447 * acpi_ec_submit_flushable_request() - Increase the reference count unless
448 * the flush operation is not in
452 * This function must be used before taking a new action that should hold
453 * the reference count. If this function returns false, then the action
454 * must be discarded or it will prevent the flush operation from being
457 static bool acpi_ec_submit_flushable_request(struct acpi_ec *ec)
459 if (!acpi_ec_started(ec))
461 acpi_ec_submit_request(ec);
465 static void acpi_ec_submit_query(struct acpi_ec *ec)
467 acpi_ec_mask_gpe(ec);
468 if (!acpi_ec_event_enabled(ec))
470 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) {
471 ec_dbg_evt("Command(%s) submitted/blocked",
472 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY));
473 ec->nr_pending_queries++;
474 schedule_work(&ec->work);
478 static void acpi_ec_complete_query(struct acpi_ec *ec)
480 if (test_and_clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags))
481 ec_dbg_evt("Command(%s) unblocked",
482 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY));
483 acpi_ec_unmask_gpe(ec);
486 static inline void __acpi_ec_enable_event(struct acpi_ec *ec)
488 if (!test_and_set_bit(EC_FLAGS_QUERY_ENABLED, &ec->flags))
489 ec_log_drv("event unblocked");
491 * Unconditionally invoke this once after enabling the event
492 * handling mechanism to detect the pending events.
494 advance_transaction(ec);
497 static inline void __acpi_ec_disable_event(struct acpi_ec *ec)
499 if (test_and_clear_bit(EC_FLAGS_QUERY_ENABLED, &ec->flags))
500 ec_log_drv("event blocked");
504 * Process _Q events that might have accumulated in the EC.
505 * Run with locked ec mutex.
507 static void acpi_ec_clear(struct acpi_ec *ec)
512 for (i = 0; i < ACPI_EC_CLEAR_MAX; i++) {
513 status = acpi_ec_query(ec, &value);
514 if (status || !value)
517 if (unlikely(i == ACPI_EC_CLEAR_MAX))
518 pr_warn("Warning: Maximum of %d stale EC events cleared\n", i);
520 pr_info("%d stale EC events cleared\n", i);
523 static void acpi_ec_enable_event(struct acpi_ec *ec)
527 spin_lock_irqsave(&ec->lock, flags);
528 if (acpi_ec_started(ec))
529 __acpi_ec_enable_event(ec);
530 spin_unlock_irqrestore(&ec->lock, flags);
532 /* Drain additional events if hardware requires that */
533 if (EC_FLAGS_CLEAR_ON_RESUME)
537 #ifdef CONFIG_PM_SLEEP
538 static bool acpi_ec_query_flushed(struct acpi_ec *ec)
543 spin_lock_irqsave(&ec->lock, flags);
544 flushed = !ec->nr_pending_queries;
545 spin_unlock_irqrestore(&ec->lock, flags);
549 static void __acpi_ec_flush_event(struct acpi_ec *ec)
552 * When ec_freeze_events is true, we need to flush events in
553 * the proper position before entering the noirq stage.
555 wait_event(ec->wait, acpi_ec_query_flushed(ec));
557 flush_workqueue(ec_query_wq);
560 static void acpi_ec_disable_event(struct acpi_ec *ec)
564 spin_lock_irqsave(&ec->lock, flags);
565 __acpi_ec_disable_event(ec);
566 spin_unlock_irqrestore(&ec->lock, flags);
567 __acpi_ec_flush_event(ec);
570 void acpi_ec_flush_work(void)
573 __acpi_ec_flush_event(first_ec);
575 flush_scheduled_work();
577 #endif /* CONFIG_PM_SLEEP */
579 static bool acpi_ec_guard_event(struct acpi_ec *ec)
584 spin_lock_irqsave(&ec->lock, flags);
586 * If firmware SCI_EVT clearing timing is "event", we actually
587 * don't know when the SCI_EVT will be cleared by firmware after
588 * evaluating _Qxx, so we need to re-check SCI_EVT after waiting an
591 * The guarding period begins when EC_FLAGS_QUERY_PENDING is
592 * flagged, which means SCI_EVT check has just been performed.
593 * But if the current transaction is ACPI_EC_COMMAND_QUERY, the
594 * guarding should have already been performed (via
595 * EC_FLAGS_QUERY_GUARDING) and should not be applied so that the
596 * ACPI_EC_COMMAND_QUERY transaction can be transitioned into
597 * ACPI_EC_COMMAND_POLL state immediately.
599 if (ec_event_clearing == ACPI_EC_EVT_TIMING_STATUS ||
600 ec_event_clearing == ACPI_EC_EVT_TIMING_QUERY ||
601 !test_bit(EC_FLAGS_QUERY_PENDING, &ec->flags) ||
602 (ec->curr && ec->curr->command == ACPI_EC_COMMAND_QUERY))
604 spin_unlock_irqrestore(&ec->lock, flags);
608 static int ec_transaction_polled(struct acpi_ec *ec)
613 spin_lock_irqsave(&ec->lock, flags);
614 if (ec->curr && (ec->curr->flags & ACPI_EC_COMMAND_POLL))
616 spin_unlock_irqrestore(&ec->lock, flags);
620 static int ec_transaction_completed(struct acpi_ec *ec)
625 spin_lock_irqsave(&ec->lock, flags);
626 if (ec->curr && (ec->curr->flags & ACPI_EC_COMMAND_COMPLETE))
628 spin_unlock_irqrestore(&ec->lock, flags);
632 static inline void ec_transaction_transition(struct acpi_ec *ec, unsigned long flag)
634 ec->curr->flags |= flag;
635 if (ec->curr->command == ACPI_EC_COMMAND_QUERY) {
636 if (ec_event_clearing == ACPI_EC_EVT_TIMING_STATUS &&
637 flag == ACPI_EC_COMMAND_POLL)
638 acpi_ec_complete_query(ec);
639 if (ec_event_clearing == ACPI_EC_EVT_TIMING_QUERY &&
640 flag == ACPI_EC_COMMAND_COMPLETE)
641 acpi_ec_complete_query(ec);
642 if (ec_event_clearing == ACPI_EC_EVT_TIMING_EVENT &&
643 flag == ACPI_EC_COMMAND_COMPLETE)
644 set_bit(EC_FLAGS_QUERY_GUARDING, &ec->flags);
648 static void advance_transaction(struct acpi_ec *ec)
650 struct transaction *t;
654 ec_dbg_stm("%s (%d)", in_interrupt() ? "IRQ" : "TASK",
657 * By always clearing STS before handling all indications, we can
658 * ensure a hardware STS 0->1 change after this clearing can always
659 * trigger a GPE interrupt.
661 acpi_ec_clear_gpe(ec);
662 status = acpi_ec_read_status(ec);
665 * Another IRQ or a guarded polling mode advancement is detected,
666 * the next QR_EC submission is then allowed.
668 if (!t || !(t->flags & ACPI_EC_COMMAND_POLL)) {
669 if (ec_event_clearing == ACPI_EC_EVT_TIMING_EVENT &&
670 (!ec->nr_pending_queries ||
671 test_bit(EC_FLAGS_QUERY_GUARDING, &ec->flags))) {
672 clear_bit(EC_FLAGS_QUERY_GUARDING, &ec->flags);
673 acpi_ec_complete_query(ec);
678 if (t->flags & ACPI_EC_COMMAND_POLL) {
679 if (t->wlen > t->wi) {
680 if ((status & ACPI_EC_FLAG_IBF) == 0)
681 acpi_ec_write_data(ec, t->wdata[t->wi++]);
684 } else if (t->rlen > t->ri) {
685 if ((status & ACPI_EC_FLAG_OBF) == 1) {
686 t->rdata[t->ri++] = acpi_ec_read_data(ec);
687 if (t->rlen == t->ri) {
688 ec_transaction_transition(ec, ACPI_EC_COMMAND_COMPLETE);
689 if (t->command == ACPI_EC_COMMAND_QUERY)
690 ec_dbg_evt("Command(%s) completed by hardware",
691 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY));
696 } else if (t->wlen == t->wi &&
697 (status & ACPI_EC_FLAG_IBF) == 0) {
698 ec_transaction_transition(ec, ACPI_EC_COMMAND_COMPLETE);
703 if (EC_FLAGS_QUERY_HANDSHAKE &&
704 !(status & ACPI_EC_FLAG_SCI) &&
705 (t->command == ACPI_EC_COMMAND_QUERY)) {
706 ec_transaction_transition(ec, ACPI_EC_COMMAND_POLL);
707 t->rdata[t->ri++] = 0x00;
708 ec_transaction_transition(ec, ACPI_EC_COMMAND_COMPLETE);
709 ec_dbg_evt("Command(%s) completed by software",
710 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY));
712 } else if ((status & ACPI_EC_FLAG_IBF) == 0) {
713 acpi_ec_write_cmd(ec, t->command);
714 ec_transaction_transition(ec, ACPI_EC_COMMAND_POLL);
721 * If SCI bit is set, then don't think it's a false IRQ
722 * otherwise will take a not handled IRQ as a false one.
724 if (!(status & ACPI_EC_FLAG_SCI)) {
725 if (in_interrupt() && t) {
726 if (t->irq_count < ec_storm_threshold)
728 /* Allow triggering on 0 threshold */
729 if (t->irq_count == ec_storm_threshold)
730 acpi_ec_mask_gpe(ec);
734 if (status & ACPI_EC_FLAG_SCI)
735 acpi_ec_submit_query(ec);
736 if (wakeup && in_interrupt())
740 static void start_transaction(struct acpi_ec *ec)
742 ec->curr->irq_count = ec->curr->wi = ec->curr->ri = 0;
746 static int ec_guard(struct acpi_ec *ec)
748 unsigned long guard = usecs_to_jiffies(ec->polling_guard);
749 unsigned long timeout = ec->timestamp + guard;
751 /* Ensure guarding period before polling EC status */
753 if (ec->busy_polling) {
754 /* Perform busy polling */
755 if (ec_transaction_completed(ec))
757 udelay(jiffies_to_usecs(guard));
760 * Perform wait polling
761 * 1. Wait the transaction to be completed by the
762 * GPE handler after the transaction enters
763 * ACPI_EC_COMMAND_POLL state.
764 * 2. A special guarding logic is also required
765 * for event clearing mode "event" before the
766 * transaction enters ACPI_EC_COMMAND_POLL
769 if (!ec_transaction_polled(ec) &&
770 !acpi_ec_guard_event(ec))
772 if (wait_event_timeout(ec->wait,
773 ec_transaction_completed(ec),
777 } while (time_before(jiffies, timeout));
781 static int ec_poll(struct acpi_ec *ec)
784 int repeat = 5; /* number of command restarts */
787 unsigned long delay = jiffies +
788 msecs_to_jiffies(ec_delay);
792 spin_lock_irqsave(&ec->lock, flags);
793 advance_transaction(ec);
794 spin_unlock_irqrestore(&ec->lock, flags);
795 } while (time_before(jiffies, delay));
796 pr_debug("controller reset, restart transaction\n");
797 spin_lock_irqsave(&ec->lock, flags);
798 start_transaction(ec);
799 spin_unlock_irqrestore(&ec->lock, flags);
804 static int acpi_ec_transaction_unlocked(struct acpi_ec *ec,
805 struct transaction *t)
810 /* start transaction */
811 spin_lock_irqsave(&ec->lock, tmp);
812 /* Enable GPE for command processing (IBF=0/OBF=1) */
813 if (!acpi_ec_submit_flushable_request(ec)) {
817 ec_dbg_ref(ec, "Increase command");
818 /* following two actions should be kept atomic */
820 ec_dbg_req("Command(%s) started", acpi_ec_cmd_string(t->command));
821 start_transaction(ec);
822 spin_unlock_irqrestore(&ec->lock, tmp);
826 spin_lock_irqsave(&ec->lock, tmp);
827 if (t->irq_count == ec_storm_threshold)
828 acpi_ec_unmask_gpe(ec);
829 ec_dbg_req("Command(%s) stopped", acpi_ec_cmd_string(t->command));
831 /* Disable GPE for command processing (IBF=0/OBF=1) */
832 acpi_ec_complete_request(ec);
833 ec_dbg_ref(ec, "Decrease command");
835 spin_unlock_irqrestore(&ec->lock, tmp);
839 static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t)
844 if (!ec || (!t) || (t->wlen && !t->wdata) || (t->rlen && !t->rdata))
847 memset(t->rdata, 0, t->rlen);
849 mutex_lock(&ec->mutex);
850 if (ec->global_lock) {
851 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
852 if (ACPI_FAILURE(status)) {
858 status = acpi_ec_transaction_unlocked(ec, t);
861 acpi_release_global_lock(glk);
863 mutex_unlock(&ec->mutex);
867 static int acpi_ec_burst_enable(struct acpi_ec *ec)
870 struct transaction t = {.command = ACPI_EC_BURST_ENABLE,
871 .wdata = NULL, .rdata = &d,
872 .wlen = 0, .rlen = 1};
874 return acpi_ec_transaction(ec, &t);
877 static int acpi_ec_burst_disable(struct acpi_ec *ec)
879 struct transaction t = {.command = ACPI_EC_BURST_DISABLE,
880 .wdata = NULL, .rdata = NULL,
881 .wlen = 0, .rlen = 0};
883 return (acpi_ec_read_status(ec) & ACPI_EC_FLAG_BURST) ?
884 acpi_ec_transaction(ec, &t) : 0;
887 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 *data)
891 struct transaction t = {.command = ACPI_EC_COMMAND_READ,
892 .wdata = &address, .rdata = &d,
893 .wlen = 1, .rlen = 1};
895 result = acpi_ec_transaction(ec, &t);
900 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
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};
907 return acpi_ec_transaction(ec, &t);
910 int ec_read(u8 addr, u8 *val)
918 err = acpi_ec_read(first_ec, addr, &temp_data);
926 EXPORT_SYMBOL(ec_read);
928 int ec_write(u8 addr, u8 val)
935 err = acpi_ec_write(first_ec, addr, val);
939 EXPORT_SYMBOL(ec_write);
941 int ec_transaction(u8 command,
942 const u8 *wdata, unsigned wdata_len,
943 u8 *rdata, unsigned rdata_len)
945 struct transaction t = {.command = command,
946 .wdata = wdata, .rdata = rdata,
947 .wlen = wdata_len, .rlen = rdata_len};
952 return acpi_ec_transaction(first_ec, &t);
954 EXPORT_SYMBOL(ec_transaction);
956 /* Get the handle to the EC device */
957 acpi_handle ec_get_handle(void)
961 return first_ec->handle;
963 EXPORT_SYMBOL(ec_get_handle);
965 static void acpi_ec_start(struct acpi_ec *ec, bool resuming)
969 spin_lock_irqsave(&ec->lock, flags);
970 if (!test_and_set_bit(EC_FLAGS_STARTED, &ec->flags)) {
971 ec_dbg_drv("Starting EC");
972 /* Enable GPE for event processing (SCI_EVT=1) */
974 acpi_ec_submit_request(ec);
975 ec_dbg_ref(ec, "Increase driver");
977 ec_log_drv("EC started");
979 spin_unlock_irqrestore(&ec->lock, flags);
982 static bool acpi_ec_stopped(struct acpi_ec *ec)
987 spin_lock_irqsave(&ec->lock, flags);
988 flushed = acpi_ec_flushed(ec);
989 spin_unlock_irqrestore(&ec->lock, flags);
993 static void acpi_ec_stop(struct acpi_ec *ec, bool suspending)
997 spin_lock_irqsave(&ec->lock, flags);
998 if (acpi_ec_started(ec)) {
999 ec_dbg_drv("Stopping EC");
1000 set_bit(EC_FLAGS_STOPPED, &ec->flags);
1001 spin_unlock_irqrestore(&ec->lock, flags);
1002 wait_event(ec->wait, acpi_ec_stopped(ec));
1003 spin_lock_irqsave(&ec->lock, flags);
1004 /* Disable GPE for event processing (SCI_EVT=1) */
1006 acpi_ec_complete_request(ec);
1007 ec_dbg_ref(ec, "Decrease driver");
1008 } else if (!ec_freeze_events)
1009 __acpi_ec_disable_event(ec);
1010 clear_bit(EC_FLAGS_STARTED, &ec->flags);
1011 clear_bit(EC_FLAGS_STOPPED, &ec->flags);
1012 ec_log_drv("EC stopped");
1014 spin_unlock_irqrestore(&ec->lock, flags);
1017 static void acpi_ec_enter_noirq(struct acpi_ec *ec)
1019 unsigned long flags;
1021 spin_lock_irqsave(&ec->lock, flags);
1022 ec->busy_polling = true;
1023 ec->polling_guard = 0;
1024 ec_log_drv("interrupt blocked");
1025 spin_unlock_irqrestore(&ec->lock, flags);
1028 static void acpi_ec_leave_noirq(struct acpi_ec *ec)
1030 unsigned long flags;
1032 spin_lock_irqsave(&ec->lock, flags);
1033 ec->busy_polling = ec_busy_polling;
1034 ec->polling_guard = ec_polling_guard;
1035 ec_log_drv("interrupt unblocked");
1036 spin_unlock_irqrestore(&ec->lock, flags);
1039 void acpi_ec_block_transactions(void)
1041 struct acpi_ec *ec = first_ec;
1046 mutex_lock(&ec->mutex);
1047 /* Prevent transactions from being carried out */
1048 acpi_ec_stop(ec, true);
1049 mutex_unlock(&ec->mutex);
1052 void acpi_ec_unblock_transactions(void)
1055 * Allow transactions to happen again (this function is called from
1056 * atomic context during wakeup, so we don't need to acquire the mutex).
1059 acpi_ec_start(first_ec, true);
1062 void acpi_ec_mark_gpe_for_wake(void)
1064 if (first_ec && !ec_no_wakeup)
1065 acpi_mark_gpe_for_wake(NULL, first_ec->gpe);
1068 void acpi_ec_set_gpe_wake_mask(u8 action)
1070 if (first_ec && !ec_no_wakeup)
1071 acpi_set_gpe_wake_mask(NULL, first_ec->gpe, action);
1074 void acpi_ec_dispatch_gpe(void)
1077 acpi_dispatch_gpe(NULL, first_ec->gpe);
1080 /* --------------------------------------------------------------------------
1082 -------------------------------------------------------------------------- */
1083 static struct acpi_ec_query_handler *
1084 acpi_ec_get_query_handler_by_value(struct acpi_ec *ec, u8 value)
1086 struct acpi_ec_query_handler *handler;
1088 mutex_lock(&ec->mutex);
1089 list_for_each_entry(handler, &ec->list, node) {
1090 if (value == handler->query_bit) {
1091 kref_get(&handler->kref);
1092 mutex_unlock(&ec->mutex);
1096 mutex_unlock(&ec->mutex);
1100 static void acpi_ec_query_handler_release(struct kref *kref)
1102 struct acpi_ec_query_handler *handler =
1103 container_of(kref, struct acpi_ec_query_handler, kref);
1108 static void acpi_ec_put_query_handler(struct acpi_ec_query_handler *handler)
1110 kref_put(&handler->kref, acpi_ec_query_handler_release);
1113 int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
1114 acpi_handle handle, acpi_ec_query_func func,
1117 struct acpi_ec_query_handler *handler =
1118 kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL);
1123 handler->query_bit = query_bit;
1124 handler->handle = handle;
1125 handler->func = func;
1126 handler->data = data;
1127 mutex_lock(&ec->mutex);
1128 kref_init(&handler->kref);
1129 list_add(&handler->node, &ec->list);
1130 mutex_unlock(&ec->mutex);
1133 EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler);
1135 static void acpi_ec_remove_query_handlers(struct acpi_ec *ec,
1136 bool remove_all, u8 query_bit)
1138 struct acpi_ec_query_handler *handler, *tmp;
1139 LIST_HEAD(free_list);
1141 mutex_lock(&ec->mutex);
1142 list_for_each_entry_safe(handler, tmp, &ec->list, node) {
1143 if (remove_all || query_bit == handler->query_bit) {
1144 list_del_init(&handler->node);
1145 list_add(&handler->node, &free_list);
1148 mutex_unlock(&ec->mutex);
1149 list_for_each_entry_safe(handler, tmp, &free_list, node)
1150 acpi_ec_put_query_handler(handler);
1153 void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit)
1155 acpi_ec_remove_query_handlers(ec, false, query_bit);
1157 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler);
1159 static struct acpi_ec_query *acpi_ec_create_query(u8 *pval)
1161 struct acpi_ec_query *q;
1162 struct transaction *t;
1164 q = kzalloc(sizeof (struct acpi_ec_query), GFP_KERNEL);
1167 INIT_WORK(&q->work, acpi_ec_event_processor);
1168 t = &q->transaction;
1169 t->command = ACPI_EC_COMMAND_QUERY;
1175 static void acpi_ec_delete_query(struct acpi_ec_query *q)
1179 acpi_ec_put_query_handler(q->handler);
1184 static void acpi_ec_event_processor(struct work_struct *work)
1186 struct acpi_ec_query *q = container_of(work, struct acpi_ec_query, work);
1187 struct acpi_ec_query_handler *handler = q->handler;
1189 ec_dbg_evt("Query(0x%02x) started", handler->query_bit);
1191 handler->func(handler->data);
1192 else if (handler->handle)
1193 acpi_evaluate_object(handler->handle, NULL, NULL, NULL);
1194 ec_dbg_evt("Query(0x%02x) stopped", handler->query_bit);
1195 acpi_ec_delete_query(q);
1198 static int acpi_ec_query(struct acpi_ec *ec, u8 *data)
1202 struct acpi_ec_query *q;
1204 q = acpi_ec_create_query(&value);
1209 * Query the EC to find out which _Qxx method we need to evaluate.
1210 * Note that successful completion of the query causes the ACPI_EC_SCI
1211 * bit to be cleared (and thus clearing the interrupt source).
1213 result = acpi_ec_transaction(ec, &q->transaction);
1219 q->handler = acpi_ec_get_query_handler_by_value(ec, value);
1226 * It is reported that _Qxx are evaluated in a parallel way on
1228 * https://bugzilla.kernel.org/show_bug.cgi?id=94411
1230 * Put this log entry before schedule_work() in order to make
1231 * it appearing before any other log entries occurred during the
1232 * work queue execution.
1234 ec_dbg_evt("Query(0x%02x) scheduled", value);
1235 if (!queue_work(ec_query_wq, &q->work)) {
1236 ec_dbg_evt("Query(0x%02x) overlapped", value);
1242 acpi_ec_delete_query(q);
1248 static void acpi_ec_check_event(struct acpi_ec *ec)
1250 unsigned long flags;
1252 if (ec_event_clearing == ACPI_EC_EVT_TIMING_EVENT) {
1254 spin_lock_irqsave(&ec->lock, flags);
1256 * Take care of the SCI_EVT unless no one else is
1257 * taking care of it.
1260 advance_transaction(ec);
1261 spin_unlock_irqrestore(&ec->lock, flags);
1266 static void acpi_ec_event_handler(struct work_struct *work)
1268 unsigned long flags;
1269 struct acpi_ec *ec = container_of(work, struct acpi_ec, work);
1271 ec_dbg_evt("Event started");
1273 spin_lock_irqsave(&ec->lock, flags);
1274 while (ec->nr_pending_queries) {
1275 spin_unlock_irqrestore(&ec->lock, flags);
1276 (void)acpi_ec_query(ec, NULL);
1277 spin_lock_irqsave(&ec->lock, flags);
1278 ec->nr_pending_queries--;
1280 * Before exit, make sure that this work item can be
1281 * scheduled again. There might be QR_EC failures, leaving
1282 * EC_FLAGS_QUERY_PENDING uncleared and preventing this work
1283 * item from being scheduled again.
1285 if (!ec->nr_pending_queries) {
1286 if (ec_event_clearing == ACPI_EC_EVT_TIMING_STATUS ||
1287 ec_event_clearing == ACPI_EC_EVT_TIMING_QUERY)
1288 acpi_ec_complete_query(ec);
1291 spin_unlock_irqrestore(&ec->lock, flags);
1293 ec_dbg_evt("Event stopped");
1295 acpi_ec_check_event(ec);
1298 static u32 acpi_ec_gpe_handler(acpi_handle gpe_device,
1299 u32 gpe_number, void *data)
1301 unsigned long flags;
1302 struct acpi_ec *ec = data;
1304 spin_lock_irqsave(&ec->lock, flags);
1305 advance_transaction(ec);
1306 spin_unlock_irqrestore(&ec->lock, flags);
1307 return ACPI_INTERRUPT_HANDLED;
1310 /* --------------------------------------------------------------------------
1311 * Address Space Management
1312 * -------------------------------------------------------------------------- */
1315 acpi_ec_space_handler(u32 function, acpi_physical_address address,
1316 u32 bits, u64 *value64,
1317 void *handler_context, void *region_context)
1319 struct acpi_ec *ec = handler_context;
1320 int result = 0, i, bytes = bits / 8;
1321 u8 *value = (u8 *)value64;
1323 if ((address > 0xFF) || !value || !handler_context)
1324 return AE_BAD_PARAMETER;
1326 if (function != ACPI_READ && function != ACPI_WRITE)
1327 return AE_BAD_PARAMETER;
1329 if (ec->busy_polling || bits > 8)
1330 acpi_ec_burst_enable(ec);
1332 for (i = 0; i < bytes; ++i, ++address, ++value)
1333 result = (function == ACPI_READ) ?
1334 acpi_ec_read(ec, address, value) :
1335 acpi_ec_write(ec, address, *value);
1337 if (ec->busy_polling || bits > 8)
1338 acpi_ec_burst_disable(ec);
1342 return AE_BAD_PARAMETER;
1344 return AE_NOT_FOUND;
1352 /* --------------------------------------------------------------------------
1354 * -------------------------------------------------------------------------- */
1357 ec_parse_io_ports(struct acpi_resource *resource, void *context);
1359 static void acpi_ec_free(struct acpi_ec *ec)
1368 static struct acpi_ec *acpi_ec_alloc(void)
1370 struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
1374 mutex_init(&ec->mutex);
1375 init_waitqueue_head(&ec->wait);
1376 INIT_LIST_HEAD(&ec->list);
1377 spin_lock_init(&ec->lock);
1378 INIT_WORK(&ec->work, acpi_ec_event_handler);
1379 ec->timestamp = jiffies;
1380 ec->busy_polling = true;
1381 ec->polling_guard = 0;
1386 acpi_ec_register_query_methods(acpi_handle handle, u32 level,
1387 void *context, void **return_value)
1390 struct acpi_buffer buffer = { sizeof(node_name), node_name };
1391 struct acpi_ec *ec = context;
1395 status = acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
1397 if (ACPI_SUCCESS(status) && sscanf(node_name, "_Q%x", &value) == 1)
1398 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL);
1403 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
1406 unsigned long long tmp = 0;
1407 struct acpi_ec *ec = context;
1409 /* clear addr values, ec_parse_io_ports depend on it */
1410 ec->command_addr = ec->data_addr = 0;
1412 status = acpi_walk_resources(handle, METHOD_NAME__CRS,
1413 ec_parse_io_ports, ec);
1414 if (ACPI_FAILURE(status))
1416 if (ec->data_addr == 0 || ec->command_addr == 0)
1419 if (boot_ec && boot_ec_is_ecdt && EC_FLAGS_IGNORE_DSDT_GPE) {
1421 * Always inherit the GPE number setting from the ECDT
1424 ec->gpe = boot_ec->gpe;
1426 /* Get GPE bit assignment (EC events). */
1427 /* TODO: Add support for _GPE returning a package */
1428 status = acpi_evaluate_integer(handle, "_GPE", NULL, &tmp);
1429 if (ACPI_FAILURE(status))
1433 /* Use the global lock for all EC transactions? */
1435 acpi_evaluate_integer(handle, "_GLK", NULL, &tmp);
1436 ec->global_lock = tmp;
1437 ec->handle = handle;
1438 return AE_CTRL_TERMINATE;
1442 * Note: This function returns an error code only when the address space
1443 * handler is not installed, which means "not able to handle
1446 static int ec_install_handlers(struct acpi_ec *ec, bool handle_events)
1450 acpi_ec_start(ec, false);
1452 if (!test_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags)) {
1453 acpi_ec_enter_noirq(ec);
1454 status = acpi_install_address_space_handler(ec->handle,
1456 &acpi_ec_space_handler,
1458 if (ACPI_FAILURE(status)) {
1459 if (status == AE_NOT_FOUND) {
1461 * Maybe OS fails in evaluating the _REG
1462 * object. The AE_NOT_FOUND error will be
1463 * ignored and OS * continue to initialize
1466 pr_err("Fail in evaluating the _REG object"
1467 " of EC device. Broken bios is suspected.\n");
1469 acpi_ec_stop(ec, false);
1473 set_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags);
1479 if (!test_bit(EC_FLAGS_EVT_HANDLER_INSTALLED, &ec->flags)) {
1480 /* Find and register all query methods */
1481 acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1,
1482 acpi_ec_register_query_methods,
1484 set_bit(EC_FLAGS_EVT_HANDLER_INSTALLED, &ec->flags);
1486 if (!test_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags)) {
1487 status = acpi_install_gpe_raw_handler(NULL, ec->gpe,
1488 ACPI_GPE_EDGE_TRIGGERED,
1489 &acpi_ec_gpe_handler, ec);
1490 /* This is not fatal as we can poll EC events */
1491 if (ACPI_SUCCESS(status)) {
1492 set_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags);
1493 acpi_ec_leave_noirq(ec);
1494 if (test_bit(EC_FLAGS_STARTED, &ec->flags) &&
1495 ec->reference_count >= 1)
1496 acpi_ec_enable_gpe(ec, true);
1499 /* EC is fully operational, allow queries */
1500 acpi_ec_enable_event(ec);
1505 static void ec_remove_handlers(struct acpi_ec *ec)
1507 if (test_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags)) {
1508 if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle,
1509 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler)))
1510 pr_err("failed to remove space handler\n");
1511 clear_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags);
1515 * Stops handling the EC transactions after removing the operation
1516 * region handler. This is required because _REG(DISCONNECT)
1517 * invoked during the removal can result in new EC transactions.
1519 * Flushes the EC requests and thus disables the GPE before
1520 * removing the GPE handler. This is required by the current ACPICA
1521 * GPE core. ACPICA GPE core will automatically disable a GPE when
1522 * it is indicated but there is no way to handle it. So the drivers
1523 * must disable the GPEs prior to removing the GPE handlers.
1525 acpi_ec_stop(ec, false);
1527 if (test_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags)) {
1528 if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe,
1529 &acpi_ec_gpe_handler)))
1530 pr_err("failed to remove gpe handler\n");
1531 clear_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags);
1533 if (test_bit(EC_FLAGS_EVT_HANDLER_INSTALLED, &ec->flags)) {
1534 acpi_ec_remove_query_handlers(ec, true, 0);
1535 clear_bit(EC_FLAGS_EVT_HANDLER_INSTALLED, &ec->flags);
1539 static int acpi_ec_setup(struct acpi_ec *ec, bool handle_events)
1543 ret = ec_install_handlers(ec, handle_events);
1547 /* First EC capable of handling transactions */
1550 acpi_handle_info(first_ec->handle, "Used as first EC\n");
1553 acpi_handle_info(ec->handle,
1554 "GPE=0x%x, EC_CMD/EC_SC=0x%lx, EC_DATA=0x%lx\n",
1555 ec->gpe, ec->command_addr, ec->data_addr);
1559 static int acpi_config_boot_ec(struct acpi_ec *ec, acpi_handle handle,
1560 bool handle_events, bool is_ecdt)
1565 * Changing the ACPI handle results in a re-configuration of the
1566 * boot EC. And if it happens after the namespace initialization,
1567 * it causes _REG evaluations.
1569 if (boot_ec && boot_ec->handle != handle)
1570 ec_remove_handlers(boot_ec);
1572 /* Unset old boot EC */
1574 acpi_ec_free(boot_ec);
1577 * ECDT device creation is split into acpi_ec_ecdt_probe() and
1578 * acpi_ec_ecdt_start(). This function takes care of completing the
1579 * ECDT parsing logic as the handle update should be performed
1580 * between the installation/uninstallation of the handlers.
1582 if (ec->handle != handle)
1583 ec->handle = handle;
1585 ret = acpi_ec_setup(ec, handle_events);
1589 /* Set new boot EC */
1592 boot_ec_is_ecdt = is_ecdt;
1595 acpi_handle_info(boot_ec->handle,
1596 "Used as boot %s EC to handle transactions%s\n",
1597 is_ecdt ? "ECDT" : "DSDT",
1598 handle_events ? " and events" : "");
1602 static bool acpi_ec_ecdt_get_handle(acpi_handle *phandle)
1604 struct acpi_table_ecdt *ecdt_ptr;
1608 status = acpi_get_table(ACPI_SIG_ECDT, 1,
1609 (struct acpi_table_header **)&ecdt_ptr);
1610 if (ACPI_FAILURE(status))
1613 status = acpi_get_handle(NULL, ecdt_ptr->id, &handle);
1614 if (ACPI_FAILURE(status))
1621 static bool acpi_is_boot_ec(struct acpi_ec *ec)
1625 if (ec->command_addr == boot_ec->command_addr &&
1626 ec->data_addr == boot_ec->data_addr)
1631 static int acpi_ec_add(struct acpi_device *device)
1633 struct acpi_ec *ec = NULL;
1635 bool is_ecdt = false;
1638 strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
1639 strcpy(acpi_device_class(device), ACPI_EC_CLASS);
1641 if (!strcmp(acpi_device_hid(device), ACPI_ECDT_HID)) {
1645 ec = acpi_ec_alloc();
1648 status = ec_parse_device(device->handle, 0, ec, NULL);
1649 if (status != AE_CTRL_TERMINATE) {
1655 if (acpi_is_boot_ec(ec)) {
1656 boot_ec_is_ecdt = is_ecdt;
1659 * Trust PNP0C09 namespace location rather than
1660 * ECDT ID. But trust ECDT GPE rather than _GPE
1661 * because of ASUS quirks, so do not change
1662 * boot_ec->gpe to ec->gpe.
1664 boot_ec->handle = ec->handle;
1665 acpi_handle_debug(ec->handle, "duplicated.\n");
1669 ret = acpi_config_boot_ec(ec, ec->handle, true, is_ecdt);
1671 ret = acpi_ec_setup(ec, true);
1675 device->driver_data = ec;
1677 ret = !!request_region(ec->data_addr, 1, "EC data");
1678 WARN(!ret, "Could not request EC data io port 0x%lx", ec->data_addr);
1679 ret = !!request_region(ec->command_addr, 1, "EC cmd");
1680 WARN(!ret, "Could not request EC cmd io port 0x%lx", ec->command_addr);
1683 /* Reprobe devices depending on the EC */
1684 acpi_walk_dep_device_list(ec->handle);
1686 acpi_handle_debug(ec->handle, "enumerated.\n");
1691 acpi_ec_remove_query_handlers(ec, true, 0);
1698 static int acpi_ec_remove(struct acpi_device *device)
1705 ec = acpi_driver_data(device);
1706 release_region(ec->data_addr, 1);
1707 release_region(ec->command_addr, 1);
1708 device->driver_data = NULL;
1709 if (ec != boot_ec) {
1710 ec_remove_handlers(ec);
1717 ec_parse_io_ports(struct acpi_resource *resource, void *context)
1719 struct acpi_ec *ec = context;
1721 if (resource->type != ACPI_RESOURCE_TYPE_IO)
1725 * The first address region returned is the data port, and
1726 * the second address region returned is the status/command
1729 if (ec->data_addr == 0)
1730 ec->data_addr = resource->data.io.minimum;
1731 else if (ec->command_addr == 0)
1732 ec->command_addr = resource->data.io.minimum;
1734 return AE_CTRL_TERMINATE;
1739 static const struct acpi_device_id ec_device_ids[] = {
1746 * This function is not Windows-compatible as Windows never enumerates the
1747 * namespace EC before the main ACPI device enumeration process. It is
1748 * retained for historical reason and will be deprecated in the future.
1750 int __init acpi_ec_dsdt_probe(void)
1757 * If a platform has ECDT, there is no need to proceed as the
1758 * following probe is not a part of the ACPI device enumeration,
1759 * executing _STA is not safe, and thus this probe may risk of
1760 * picking up an invalid EC device.
1765 ec = acpi_ec_alloc();
1769 * At this point, the namespace is initialized, so start to find
1770 * the namespace objects.
1772 status = acpi_get_devices(ec_device_ids[0].id,
1773 ec_parse_device, ec, NULL);
1774 if (ACPI_FAILURE(status) || !ec->handle) {
1779 * When the DSDT EC is available, always re-configure boot EC to
1780 * have _REG evaluated. _REG can only be evaluated after the
1781 * namespace initialization.
1782 * At this point, the GPE is not fully initialized, so do not to
1783 * handle the events.
1785 ret = acpi_config_boot_ec(ec, ec->handle, false, false);
1793 * If the DSDT EC is not functioning, we still need to prepare a fully
1794 * functioning ECDT EC first in order to handle the events.
1795 * https://bugzilla.kernel.org/show_bug.cgi?id=115021
1797 static int __init acpi_ec_ecdt_start(void)
1803 /* In case acpi_ec_ecdt_start() is called after acpi_ec_add() */
1804 if (!boot_ec_is_ecdt)
1808 * At this point, the namespace and the GPE is initialized, so
1809 * start to find the namespace objects and handle the events.
1811 * Note: ec->handle can be valid if this function is called after
1812 * acpi_ec_add(), hence the fast path.
1814 if (boot_ec->handle == ACPI_ROOT_OBJECT) {
1815 if (!acpi_ec_ecdt_get_handle(&handle))
1817 boot_ec->handle = handle;
1820 /* Register to ACPI bus with PM ops attached */
1821 return acpi_bus_register_early_device(ACPI_BUS_TYPE_ECDT_EC);
1826 * Some EC firmware variations refuses to respond QR_EC when SCI_EVT is not
1827 * set, for which case, we complete the QR_EC without issuing it to the
1829 * https://bugzilla.kernel.org/show_bug.cgi?id=82611
1830 * https://bugzilla.kernel.org/show_bug.cgi?id=97381
1832 static int ec_flag_query_handshake(const struct dmi_system_id *id)
1834 pr_debug("Detected the EC firmware requiring QR_EC issued when SCI_EVT set\n");
1835 EC_FLAGS_QUERY_HANDSHAKE = 1;
1841 * On some hardware it is necessary to clear events accumulated by the EC during
1842 * sleep. These ECs stop reporting GPEs until they are manually polled, if too
1843 * many events are accumulated. (e.g. Samsung Series 5/9 notebooks)
1845 * https://bugzilla.kernel.org/show_bug.cgi?id=44161
1847 * Ideally, the EC should also be instructed NOT to accumulate events during
1848 * sleep (which Windows seems to do somehow), but the interface to control this
1849 * behaviour is not known at this time.
1851 * Models known to be affected are Samsung 530Uxx/535Uxx/540Uxx/550Pxx/900Xxx,
1852 * however it is very likely that other Samsung models are affected.
1854 * On systems which don't accumulate _Q events during sleep, this extra check
1855 * should be harmless.
1857 static int ec_clear_on_resume(const struct dmi_system_id *id)
1859 pr_debug("Detected system needing EC poll on resume.\n");
1860 EC_FLAGS_CLEAR_ON_RESUME = 1;
1861 ec_event_clearing = ACPI_EC_EVT_TIMING_STATUS;
1866 * Some ECDTs contain wrong register addresses.
1868 * https://bugzilla.kernel.org/show_bug.cgi?id=12461
1870 static int ec_correct_ecdt(const struct dmi_system_id *id)
1872 pr_debug("Detected system needing ECDT address correction.\n");
1873 EC_FLAGS_CORRECT_ECDT = 1;
1878 * Some DSDTs contain wrong GPE setting.
1879 * Asus FX502VD/VE, GL702VMK, X550VXK, X580VD
1880 * https://bugzilla.kernel.org/show_bug.cgi?id=195651
1882 static int ec_honor_ecdt_gpe(const struct dmi_system_id *id)
1884 pr_debug("Detected system needing ignore DSDT GPE setting.\n");
1885 EC_FLAGS_IGNORE_DSDT_GPE = 1;
1889 static const struct dmi_system_id ec_dmi_table[] __initconst = {
1891 ec_correct_ecdt, "MSI MS-171F", {
1892 DMI_MATCH(DMI_SYS_VENDOR, "Micro-Star"),
1893 DMI_MATCH(DMI_PRODUCT_NAME, "MS-171F"),}, NULL},
1895 ec_honor_ecdt_gpe, "ASUS FX502VD", {
1896 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
1897 DMI_MATCH(DMI_PRODUCT_NAME, "FX502VD"),}, NULL},
1899 ec_honor_ecdt_gpe, "ASUS FX502VE", {
1900 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
1901 DMI_MATCH(DMI_PRODUCT_NAME, "FX502VE"),}, NULL},
1903 ec_honor_ecdt_gpe, "ASUS GL702VMK", {
1904 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
1905 DMI_MATCH(DMI_PRODUCT_NAME, "GL702VMK"),}, NULL},
1907 ec_honor_ecdt_gpe, "ASUSTeK COMPUTER INC. X505BA", {
1908 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
1909 DMI_MATCH(DMI_PRODUCT_NAME, "X505BA"),}, NULL},
1911 ec_honor_ecdt_gpe, "ASUSTeK COMPUTER INC. X505BP", {
1912 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
1913 DMI_MATCH(DMI_PRODUCT_NAME, "X505BP"),}, NULL},
1915 ec_honor_ecdt_gpe, "ASUSTeK COMPUTER INC. X542BA", {
1916 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
1917 DMI_MATCH(DMI_PRODUCT_NAME, "X542BA"),}, NULL},
1919 ec_honor_ecdt_gpe, "ASUSTeK COMPUTER INC. X542BP", {
1920 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
1921 DMI_MATCH(DMI_PRODUCT_NAME, "X542BP"),}, NULL},
1923 ec_honor_ecdt_gpe, "ASUS X550VXK", {
1924 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
1925 DMI_MATCH(DMI_PRODUCT_NAME, "X550VXK"),}, NULL},
1927 ec_honor_ecdt_gpe, "ASUS X580VD", {
1928 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
1929 DMI_MATCH(DMI_PRODUCT_NAME, "X580VD"),}, NULL},
1931 ec_clear_on_resume, "Samsung hardware", {
1932 DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD.")}, NULL},
1936 int __init acpi_ec_ecdt_probe(void)
1940 struct acpi_table_ecdt *ecdt_ptr;
1943 ec = acpi_ec_alloc();
1947 * Generate a boot ec context
1949 dmi_check_system(ec_dmi_table);
1950 status = acpi_get_table(ACPI_SIG_ECDT, 1,
1951 (struct acpi_table_header **)&ecdt_ptr);
1952 if (ACPI_FAILURE(status)) {
1957 if (!ecdt_ptr->control.address || !ecdt_ptr->data.address) {
1960 * https://bugzilla.kernel.org/show_bug.cgi?id=11880
1966 if (EC_FLAGS_CORRECT_ECDT) {
1967 ec->command_addr = ecdt_ptr->data.address;
1968 ec->data_addr = ecdt_ptr->control.address;
1970 ec->command_addr = ecdt_ptr->control.address;
1971 ec->data_addr = ecdt_ptr->data.address;
1973 ec->gpe = ecdt_ptr->gpe;
1976 * At this point, the namespace is not initialized, so do not find
1977 * the namespace objects, or handle the events.
1979 ret = acpi_config_boot_ec(ec, ACPI_ROOT_OBJECT, false, true);
1986 #ifdef CONFIG_PM_SLEEP
1987 static int acpi_ec_suspend(struct device *dev)
1989 struct acpi_ec *ec =
1990 acpi_driver_data(to_acpi_device(dev));
1992 if (acpi_sleep_no_ec_events() && ec_freeze_events)
1993 acpi_ec_disable_event(ec);
1997 static int acpi_ec_suspend_noirq(struct device *dev)
1999 struct acpi_ec *ec = acpi_driver_data(to_acpi_device(dev));
2002 * The SCI handler doesn't run at this point, so the GPE can be
2003 * masked at the low level without side effects.
2005 if (ec_no_wakeup && test_bit(EC_FLAGS_STARTED, &ec->flags) &&
2006 ec->reference_count >= 1)
2007 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_DISABLE);
2009 if (acpi_sleep_no_ec_events())
2010 acpi_ec_enter_noirq(ec);
2015 static int acpi_ec_resume_noirq(struct device *dev)
2017 struct acpi_ec *ec = acpi_driver_data(to_acpi_device(dev));
2019 if (acpi_sleep_no_ec_events())
2020 acpi_ec_leave_noirq(ec);
2022 if (ec_no_wakeup && test_bit(EC_FLAGS_STARTED, &ec->flags) &&
2023 ec->reference_count >= 1)
2024 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_ENABLE);
2029 static int acpi_ec_resume(struct device *dev)
2031 struct acpi_ec *ec =
2032 acpi_driver_data(to_acpi_device(dev));
2034 acpi_ec_enable_event(ec);
2039 static const struct dev_pm_ops acpi_ec_pm = {
2040 SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(acpi_ec_suspend_noirq, acpi_ec_resume_noirq)
2041 SET_SYSTEM_SLEEP_PM_OPS(acpi_ec_suspend, acpi_ec_resume)
2044 static int param_set_event_clearing(const char *val,
2045 const struct kernel_param *kp)
2049 if (!strncmp(val, "status", sizeof("status") - 1)) {
2050 ec_event_clearing = ACPI_EC_EVT_TIMING_STATUS;
2051 pr_info("Assuming SCI_EVT clearing on EC_SC accesses\n");
2052 } else if (!strncmp(val, "query", sizeof("query") - 1)) {
2053 ec_event_clearing = ACPI_EC_EVT_TIMING_QUERY;
2054 pr_info("Assuming SCI_EVT clearing on QR_EC writes\n");
2055 } else if (!strncmp(val, "event", sizeof("event") - 1)) {
2056 ec_event_clearing = ACPI_EC_EVT_TIMING_EVENT;
2057 pr_info("Assuming SCI_EVT clearing on event reads\n");
2063 static int param_get_event_clearing(char *buffer,
2064 const struct kernel_param *kp)
2066 switch (ec_event_clearing) {
2067 case ACPI_EC_EVT_TIMING_STATUS:
2068 return sprintf(buffer, "status");
2069 case ACPI_EC_EVT_TIMING_QUERY:
2070 return sprintf(buffer, "query");
2071 case ACPI_EC_EVT_TIMING_EVENT:
2072 return sprintf(buffer, "event");
2074 return sprintf(buffer, "invalid");
2079 module_param_call(ec_event_clearing, param_set_event_clearing, param_get_event_clearing,
2081 MODULE_PARM_DESC(ec_event_clearing, "Assumed SCI_EVT clearing timing");
2083 static struct acpi_driver acpi_ec_driver = {
2085 .class = ACPI_EC_CLASS,
2086 .ids = ec_device_ids,
2089 .remove = acpi_ec_remove,
2091 .drv.pm = &acpi_ec_pm,
2094 static inline int acpi_ec_query_init(void)
2097 ec_query_wq = alloc_workqueue("kec_query", 0,
2105 static inline void acpi_ec_query_exit(void)
2108 destroy_workqueue(ec_query_wq);
2113 static const struct dmi_system_id acpi_ec_no_wakeup[] = {
2115 .ident = "Thinkpad X1 Carbon 6th",
2117 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
2118 DMI_MATCH(DMI_PRODUCT_FAMILY, "Thinkpad X1 Carbon 6th"),
2122 .ident = "ThinkPad X1 Carbon 6th",
2124 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
2125 DMI_MATCH(DMI_PRODUCT_FAMILY, "ThinkPad X1 Carbon 6th"),
2129 .ident = "ThinkPad X1 Yoga 3rd",
2131 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
2132 DMI_MATCH(DMI_PRODUCT_FAMILY, "ThinkPad X1 Yoga 3rd"),
2138 int __init acpi_ec_init(void)
2141 int ecdt_fail, dsdt_fail;
2143 /* register workqueue for _Qxx evaluations */
2144 result = acpi_ec_query_init();
2149 * Disable EC wakeup on following systems to prevent periodic
2150 * wakeup from EC GPE.
2152 if (dmi_check_system(acpi_ec_no_wakeup)) {
2153 ec_no_wakeup = true;
2154 pr_debug("Disabling EC wakeup on suspend-to-idle\n");
2157 /* Drivers must be started after acpi_ec_query_init() */
2158 dsdt_fail = acpi_bus_register_driver(&acpi_ec_driver);
2160 * Register ECDT to ACPI bus only when PNP0C09 probe fails. This is
2161 * useful for platforms (confirmed on ASUS X550ZE) with valid ECDT
2162 * settings but invalid DSDT settings.
2163 * https://bugzilla.kernel.org/show_bug.cgi?id=196847
2165 ecdt_fail = acpi_ec_ecdt_start();
2166 return ecdt_fail && dsdt_fail ? -ENODEV : 0;
2169 /* EC driver currently not unloadable */
2171 static void __exit acpi_ec_exit(void)
2174 acpi_bus_unregister_driver(&acpi_ec_driver);
2175 acpi_ec_query_exit();