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 */
91enum 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
106enum {
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 */
116};
117
118#define ACPI_EC_COMMAND_POLL 0x01 /* Available for command byte */
119#define ACPI_EC_COMMAND_COMPLETE 0x02 /* Completed last byte */
120
121/* ec.c is compiled in acpi namespace so this shows up as acpi.ec_delay param */
122static unsigned int ec_delay __read_mostly = ACPI_EC_DELAY;
123module_param(ec_delay, uint, 0644);
124MODULE_PARM_DESC(ec_delay, "Timeout(ms) waited until an EC command completes");
125
126static unsigned int ec_max_queries __read_mostly = ACPI_EC_MAX_QUERIES;
127module_param(ec_max_queries, uint, 0644);
128MODULE_PARM_DESC(ec_max_queries, "Maximum parallel _Qxx evaluations");
129
130static bool ec_busy_polling __read_mostly;
131module_param(ec_busy_polling, bool, 0644);
132MODULE_PARM_DESC(ec_busy_polling, "Use busy polling to advance EC transaction");
133
134static unsigned int ec_polling_guard __read_mostly = ACPI_EC_UDELAY_POLL;
135module_param(ec_polling_guard, uint, 0644);
136MODULE_PARM_DESC(ec_polling_guard, "Guard time(us) between EC accesses in polling modes");
137
138static unsigned int ec_event_clearing __read_mostly = ACPI_EC_EVT_TIMING_QUERY;
139
140/*
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.
144 */
145static unsigned int ec_storm_threshold __read_mostly = 8;
146module_param(ec_storm_threshold, uint, 0644);
147MODULE_PARM_DESC(ec_storm_threshold, "Maxim false GPE numbers not considered as GPE storm");
148
149static bool ec_freeze_events __read_mostly = false;
150module_param(ec_freeze_events, bool, 0644);
151MODULE_PARM_DESC(ec_freeze_events, "Disabling event handling during suspend/resume");
152
153static bool ec_no_wakeup __read_mostly;
154module_param(ec_no_wakeup, bool, 0644);
155MODULE_PARM_DESC(ec_no_wakeup, "Do not wake up from suspend-to-idle");
156
157struct acpi_ec_query_handler {
158 struct list_head node;
159 acpi_ec_query_func func;
160 acpi_handle handle;
161 void *data;
162 u8 query_bit;
163 struct kref kref;
164};
165
166struct transaction {
167 const u8 *wdata;
168 u8 *rdata;
169 unsigned short irq_count;
170 u8 command;
171 u8 wi;
172 u8 ri;
173 u8 wlen;
174 u8 rlen;
175 u8 flags;
176};
177
178struct acpi_ec_query {
179 struct transaction transaction;
180 struct work_struct work;
181 struct acpi_ec_query_handler *handler;
182};
183
184static int acpi_ec_query(struct acpi_ec *ec, u8 *data);
185static void advance_transaction(struct acpi_ec *ec);
186static void acpi_ec_event_handler(struct work_struct *work);
187static void acpi_ec_event_processor(struct work_struct *work);
188
189struct acpi_ec *first_ec;
190EXPORT_SYMBOL(first_ec);
191
192static struct acpi_ec *boot_ec;
193static bool boot_ec_is_ecdt = false;
194static struct workqueue_struct *ec_query_wq;
195
196static int EC_FLAGS_QUERY_HANDSHAKE; /* Needs QR_EC issued when SCI_EVT set */
197static int EC_FLAGS_CORRECT_ECDT; /* Needs ECDT port address correction */
198static int EC_FLAGS_IGNORE_DSDT_GPE; /* Needs ECDT GPE as correction setting */
199static int EC_FLAGS_CLEAR_ON_RESUME; /* Needs acpi_ec_clear() on boot/resume */
200
201/* --------------------------------------------------------------------------
202 * Logging/Debugging
203 * -------------------------------------------------------------------------- */
204
205/*
206 * Splitters used by the developers to track the boundary of the EC
207 * handling processes.
208 */
209#ifdef DEBUG
210#define EC_DBG_SEP " "
211#define EC_DBG_DRV "+++++"
212#define EC_DBG_STM "====="
213#define EC_DBG_REQ "*****"
214#define EC_DBG_EVT "#####"
215#else
216#define EC_DBG_SEP ""
217#define EC_DBG_DRV
218#define EC_DBG_STM
219#define EC_DBG_REQ
220#define EC_DBG_EVT
221#endif
222
223#define ec_log_raw(fmt, ...) \
224 pr_info(fmt "\n", ##__VA_ARGS__)
225#define ec_dbg_raw(fmt, ...) \
226 pr_debug(fmt "\n", ##__VA_ARGS__)
227#define ec_log(filter, fmt, ...) \
228 ec_log_raw(filter EC_DBG_SEP fmt EC_DBG_SEP filter, ##__VA_ARGS__)
229#define ec_dbg(filter, fmt, ...) \
230 ec_dbg_raw(filter EC_DBG_SEP fmt EC_DBG_SEP filter, ##__VA_ARGS__)
231
232#define ec_log_drv(fmt, ...) \
233 ec_log(EC_DBG_DRV, fmt, ##__VA_ARGS__)
234#define ec_dbg_drv(fmt, ...) \
235 ec_dbg(EC_DBG_DRV, fmt, ##__VA_ARGS__)
236#define ec_dbg_stm(fmt, ...) \
237 ec_dbg(EC_DBG_STM, fmt, ##__VA_ARGS__)
238#define ec_dbg_req(fmt, ...) \
239 ec_dbg(EC_DBG_REQ, fmt, ##__VA_ARGS__)
240#define ec_dbg_evt(fmt, ...) \
241 ec_dbg(EC_DBG_EVT, fmt, ##__VA_ARGS__)
242#define ec_dbg_ref(ec, fmt, ...) \
243 ec_dbg_raw("%lu: " fmt, ec->reference_count, ## __VA_ARGS__)
244
245/* --------------------------------------------------------------------------
246 * Device Flags
247 * -------------------------------------------------------------------------- */
248
249static bool acpi_ec_started(struct acpi_ec *ec)
250{
251 return test_bit(EC_FLAGS_STARTED, &ec->flags) &&
252 !test_bit(EC_FLAGS_STOPPED, &ec->flags);
253}
254
255static bool acpi_ec_event_enabled(struct acpi_ec *ec)
256{
257 /*
258 * There is an OSPM early stage logic. During the early stages
259 * (boot/resume), OSPMs shouldn't enable the event handling, only
260 * the EC transactions are allowed to be performed.
261 */
262 if (!test_bit(EC_FLAGS_QUERY_ENABLED, &ec->flags))
263 return false;
264 /*
265 * However, disabling the event handling is experimental for late
266 * stage (suspend), and is controlled by the boot parameter of
267 * "ec_freeze_events":
268 * 1. true: The EC event handling is disabled before entering
269 * the noirq stage.
270 * 2. false: The EC event handling is automatically disabled as
271 * soon as the EC driver is stopped.
272 */
273 if (ec_freeze_events)
274 return acpi_ec_started(ec);
275 else
276 return test_bit(EC_FLAGS_STARTED, &ec->flags);
277}
278
279static bool acpi_ec_flushed(struct acpi_ec *ec)
280{
281 return ec->reference_count == 1;
282}
283
284/* --------------------------------------------------------------------------
285 * EC Registers
286 * -------------------------------------------------------------------------- */
287
288static inline u8 acpi_ec_read_status(struct acpi_ec *ec)
289{
290 u8 x = inb(ec->command_addr);
291
292 ec_dbg_raw("EC_SC(R) = 0x%2.2x "
293 "SCI_EVT=%d BURST=%d CMD=%d IBF=%d OBF=%d",
294 x,
295 !!(x & ACPI_EC_FLAG_SCI),
296 !!(x & ACPI_EC_FLAG_BURST),
297 !!(x & ACPI_EC_FLAG_CMD),
298 !!(x & ACPI_EC_FLAG_IBF),
299 !!(x & ACPI_EC_FLAG_OBF));
300 return x;
301}
302
303static inline u8 acpi_ec_read_data(struct acpi_ec *ec)
304{
305 u8 x = inb(ec->data_addr);
306
307 ec->timestamp = jiffies;
308 ec_dbg_raw("EC_DATA(R) = 0x%2.2x", x);
309 return x;
310}
311
312static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command)
313{
314 ec_dbg_raw("EC_SC(W) = 0x%2.2x", command);
315 outb(command, ec->command_addr);
316 ec->timestamp = jiffies;
317}
318
319static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data)
320{
321 ec_dbg_raw("EC_DATA(W) = 0x%2.2x", data);
322 outb(data, ec->data_addr);
323 ec->timestamp = jiffies;
324}
325
326#if defined(DEBUG) || defined(CONFIG_DYNAMIC_DEBUG)
327static const char *acpi_ec_cmd_string(u8 cmd)
328{
329 switch (cmd) {
330 case 0x80:
331 return "RD_EC";
332 case 0x81:
333 return "WR_EC";
334 case 0x82:
335 return "BE_EC";
336 case 0x83:
337 return "BD_EC";
338 case 0x84:
339 return "QR_EC";
340 }
341 return "UNKNOWN";
342}
343#else
344#define acpi_ec_cmd_string(cmd) "UNDEF"
345#endif
346
347/* --------------------------------------------------------------------------
348 * GPE Registers
349 * -------------------------------------------------------------------------- */
350
351static inline bool acpi_ec_is_gpe_raised(struct acpi_ec *ec)
352{
353 acpi_event_status gpe_status = 0;
354
355 (void)acpi_get_gpe_status(NULL, ec->gpe, &gpe_status);
356 return (gpe_status & ACPI_EVENT_FLAG_STATUS_SET) ? true : false;
357}
358
359static inline void acpi_ec_enable_gpe(struct acpi_ec *ec, bool open)
360{
361 if (open)
362 acpi_enable_gpe(NULL, ec->gpe);
363 else {
364 BUG_ON(ec->reference_count < 1);
365 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_ENABLE);
366 }
367 if (acpi_ec_is_gpe_raised(ec)) {
368 /*
369 * On some platforms, EN=1 writes cannot trigger GPE. So
370 * software need to manually trigger a pseudo GPE event on
371 * EN=1 writes.
372 */
373 ec_dbg_raw("Polling quirk");
374 advance_transaction(ec);
375 }
376}
377
378static inline void acpi_ec_disable_gpe(struct acpi_ec *ec, bool close)
379{
380 if (close)
381 acpi_disable_gpe(NULL, ec->gpe);
382 else {
383 BUG_ON(ec->reference_count < 1);
384 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_DISABLE);
385 }
386}
387
388static inline void acpi_ec_clear_gpe(struct acpi_ec *ec)
389{
390 /*
391 * GPE STS is a W1C register, which means:
392 * 1. Software can clear it without worrying about clearing other
393 * GPEs' STS bits when the hardware sets them in parallel.
394 * 2. As long as software can ensure only clearing it when it is
395 * set, hardware won't set it in parallel.
396 * So software can clear GPE in any contexts.
397 * Warning: do not move the check into advance_transaction() as the
398 * EC commands will be sent without GPE raised.
399 */
400 if (!acpi_ec_is_gpe_raised(ec))
401 return;
402 acpi_clear_gpe(NULL, ec->gpe);
403}
404
405/* --------------------------------------------------------------------------
406 * Transaction Management
407 * -------------------------------------------------------------------------- */
408
409static void acpi_ec_submit_request(struct acpi_ec *ec)
410{
411 ec->reference_count++;
412 if (test_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags) &&
413 ec->reference_count == 1)
414 acpi_ec_enable_gpe(ec, true);
415}
416
417static void acpi_ec_complete_request(struct acpi_ec *ec)
418{
419 bool flushed = false;
420
421 ec->reference_count--;
422 if (test_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags) &&
423 ec->reference_count == 0)
424 acpi_ec_disable_gpe(ec, true);
425 flushed = acpi_ec_flushed(ec);
426 if (flushed)
427 wake_up(&ec->wait);
428}
429
430static void acpi_ec_mask_gpe(struct acpi_ec *ec)
431{
432 if (!test_bit(EC_FLAGS_GPE_MASKED, &ec->flags)) {
433 acpi_ec_disable_gpe(ec, false);
434 ec_dbg_drv("Polling enabled");
435 set_bit(EC_FLAGS_GPE_MASKED, &ec->flags);
436 }
437}
438
439static void acpi_ec_unmask_gpe(struct acpi_ec *ec)
440{
441 if (test_bit(EC_FLAGS_GPE_MASKED, &ec->flags)) {
442 clear_bit(EC_FLAGS_GPE_MASKED, &ec->flags);
443 acpi_ec_enable_gpe(ec, false);
444 ec_dbg_drv("Polling disabled");
445 }
446}
447
448/*
449 * acpi_ec_submit_flushable_request() - Increase the reference count unless
450 * the flush operation is not in
451 * progress
452 * @ec: the EC device
453 *
454 * This function must be used before taking a new action that should hold
455 * the reference count. If this function returns false, then the action
456 * must be discarded or it will prevent the flush operation from being
457 * completed.
458 */
459static bool acpi_ec_submit_flushable_request(struct acpi_ec *ec)
460{
461 if (!acpi_ec_started(ec))
462 return false;
463 acpi_ec_submit_request(ec);
464 return true;
465}
466
467static void acpi_ec_submit_query(struct acpi_ec *ec)
468{
469 acpi_ec_mask_gpe(ec);
470 if (!acpi_ec_event_enabled(ec))
471 return;
472 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) {
473 ec_dbg_evt("Command(%s) submitted/blocked",
474 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY));
475 ec->nr_pending_queries++;
476 schedule_work(&ec->work);
477 }
478}
479
480static void acpi_ec_complete_query(struct acpi_ec *ec)
481{
482 if (test_and_clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags))
483 ec_dbg_evt("Command(%s) unblocked",
484 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY));
485 acpi_ec_unmask_gpe(ec);
486}
487
488static inline void __acpi_ec_enable_event(struct acpi_ec *ec)
489{
490 if (!test_and_set_bit(EC_FLAGS_QUERY_ENABLED, &ec->flags))
491 ec_log_drv("event unblocked");
492 /*
493 * Unconditionally invoke this once after enabling the event
494 * handling mechanism to detect the pending events.
495 */
496 advance_transaction(ec);
497}
498
499static inline void __acpi_ec_disable_event(struct acpi_ec *ec)
500{
501 if (test_and_clear_bit(EC_FLAGS_QUERY_ENABLED, &ec->flags))
502 ec_log_drv("event blocked");
503}
504
505/*
506 * Process _Q events that might have accumulated in the EC.
507 * Run with locked ec mutex.
508 */
509static void acpi_ec_clear(struct acpi_ec *ec)
510{
511 int i, status;
512 u8 value = 0;
513
514 for (i = 0; i < ACPI_EC_CLEAR_MAX; i++) {
515 status = acpi_ec_query(ec, &value);
516 if (status || !value)
517 break;
518 }
519 if (unlikely(i == ACPI_EC_CLEAR_MAX))
520 pr_warn("Warning: Maximum of %d stale EC events cleared\n", i);
521 else
522 pr_info("%d stale EC events cleared\n", i);
523}
524
525static void acpi_ec_enable_event(struct acpi_ec *ec)
526{
527 unsigned long flags;
528
529 spin_lock_irqsave(&ec->lock, flags);
530 if (acpi_ec_started(ec))
531 __acpi_ec_enable_event(ec);
532 spin_unlock_irqrestore(&ec->lock, flags);
533
534 /* Drain additional events if hardware requires that */
535 if (EC_FLAGS_CLEAR_ON_RESUME)
536 acpi_ec_clear(ec);
537}
538
539#ifdef CONFIG_PM_SLEEP
540static bool acpi_ec_query_flushed(struct acpi_ec *ec)
541{
542 bool flushed;
543 unsigned long flags;
544
545 spin_lock_irqsave(&ec->lock, flags);
546 flushed = !ec->nr_pending_queries;
547 spin_unlock_irqrestore(&ec->lock, flags);
548 return flushed;
549}
550
551static void __acpi_ec_flush_event(struct acpi_ec *ec)
552{
553 /*
554 * When ec_freeze_events is true, we need to flush events in
555 * the proper position before entering the noirq stage.
556 */
557 wait_event(ec->wait, acpi_ec_query_flushed(ec));
558 if (ec_query_wq)
559 flush_workqueue(ec_query_wq);
560}
561
562static void acpi_ec_disable_event(struct acpi_ec *ec)
563{
564 unsigned long flags;
565
566 spin_lock_irqsave(&ec->lock, flags);
567 __acpi_ec_disable_event(ec);
568 spin_unlock_irqrestore(&ec->lock, flags);
569 __acpi_ec_flush_event(ec);
570}
571
572void acpi_ec_flush_work(void)
573{
574 if (first_ec)
575 __acpi_ec_flush_event(first_ec);
576
577 flush_scheduled_work();
578}
579#endif /* CONFIG_PM_SLEEP */
580
581static bool acpi_ec_guard_event(struct acpi_ec *ec)
582{
583 bool guarded = true;
584 unsigned long flags;
585
586 spin_lock_irqsave(&ec->lock, flags);
587 /*
588 * If firmware SCI_EVT clearing timing is "event", we actually
589 * don't know when the SCI_EVT will be cleared by firmware after
590 * evaluating _Qxx, so we need to re-check SCI_EVT after waiting an
591 * acceptable period.
592 *
593 * The guarding period begins when EC_FLAGS_QUERY_PENDING is
594 * flagged, which means SCI_EVT check has just been performed.
595 * But if the current transaction is ACPI_EC_COMMAND_QUERY, the
596 * guarding should have already been performed (via
597 * EC_FLAGS_QUERY_GUARDING) and should not be applied so that the
598 * ACPI_EC_COMMAND_QUERY transaction can be transitioned into
599 * ACPI_EC_COMMAND_POLL state immediately.
600 */
601 if (ec_event_clearing == ACPI_EC_EVT_TIMING_STATUS ||
602 ec_event_clearing == ACPI_EC_EVT_TIMING_QUERY ||
603 !test_bit(EC_FLAGS_QUERY_PENDING, &ec->flags) ||
604 (ec->curr && ec->curr->command == ACPI_EC_COMMAND_QUERY))
605 guarded = false;
606 spin_unlock_irqrestore(&ec->lock, flags);
607 return guarded;
608}
609
610static int ec_transaction_polled(struct acpi_ec *ec)
611{
612 unsigned long flags;
613 int ret = 0;
614
615 spin_lock_irqsave(&ec->lock, flags);
616 if (ec->curr && (ec->curr->flags & ACPI_EC_COMMAND_POLL))
617 ret = 1;
618 spin_unlock_irqrestore(&ec->lock, flags);
619 return ret;
620}
621
622static int ec_transaction_completed(struct acpi_ec *ec)
623{
624 unsigned long flags;
625 int ret = 0;
626
627 spin_lock_irqsave(&ec->lock, flags);
628 if (ec->curr && (ec->curr->flags & ACPI_EC_COMMAND_COMPLETE))
629 ret = 1;
630 spin_unlock_irqrestore(&ec->lock, flags);
631 return ret;
632}
633
634static inline void ec_transaction_transition(struct acpi_ec *ec, unsigned long flag)
635{
636 ec->curr->flags |= flag;
637 if (ec->curr->command == ACPI_EC_COMMAND_QUERY) {
638 if (ec_event_clearing == ACPI_EC_EVT_TIMING_STATUS &&
639 flag == ACPI_EC_COMMAND_POLL)
640 acpi_ec_complete_query(ec);
641 if (ec_event_clearing == ACPI_EC_EVT_TIMING_QUERY &&
642 flag == ACPI_EC_COMMAND_COMPLETE)
643 acpi_ec_complete_query(ec);
644 if (ec_event_clearing == ACPI_EC_EVT_TIMING_EVENT &&
645 flag == ACPI_EC_COMMAND_COMPLETE)
646 set_bit(EC_FLAGS_QUERY_GUARDING, &ec->flags);
647 }
648}
649
650static void advance_transaction(struct acpi_ec *ec)
651{
652 struct transaction *t;
653 u8 status;
654 bool wakeup = false;
655
656 ec_dbg_stm("%s (%d)", in_interrupt() ? "IRQ" : "TASK",
657 smp_processor_id());
658 /*
659 * By always clearing STS before handling all indications, we can
660 * ensure a hardware STS 0->1 change after this clearing can always
661 * trigger a GPE interrupt.
662 */
663 acpi_ec_clear_gpe(ec);
664 status = acpi_ec_read_status(ec);
665 t = ec->curr;
666 /*
667 * Another IRQ or a guarded polling mode advancement is detected,
668 * the next QR_EC submission is then allowed.
669 */
670 if (!t || !(t->flags & ACPI_EC_COMMAND_POLL)) {
671 if (ec_event_clearing == ACPI_EC_EVT_TIMING_EVENT &&
672 (!ec->nr_pending_queries ||
673 test_bit(EC_FLAGS_QUERY_GUARDING, &ec->flags))) {
674 clear_bit(EC_FLAGS_QUERY_GUARDING, &ec->flags);
675 acpi_ec_complete_query(ec);
676 }
677 }
678 if (!t)
679 goto err;
680 if (t->flags & ACPI_EC_COMMAND_POLL) {
681 if (t->wlen > t->wi) {
682 if ((status & ACPI_EC_FLAG_IBF) == 0)
683 acpi_ec_write_data(ec, t->wdata[t->wi++]);
684 else
685 goto err;
686 } else if (t->rlen > t->ri) {
687 if ((status & ACPI_EC_FLAG_OBF) == 1) {
688 t->rdata[t->ri++] = acpi_ec_read_data(ec);
689 if (t->rlen == t->ri) {
690 ec_transaction_transition(ec, ACPI_EC_COMMAND_COMPLETE);
691 if (t->command == ACPI_EC_COMMAND_QUERY)
692 ec_dbg_evt("Command(%s) completed by hardware",
693 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY));
694 wakeup = true;
695 }
696 } else
697 goto err;
698 } else if (t->wlen == t->wi &&
699 (status & ACPI_EC_FLAG_IBF) == 0) {
700 ec_transaction_transition(ec, ACPI_EC_COMMAND_COMPLETE);
701 wakeup = true;
702 }
703 goto out;
704 } else {
705 if (EC_FLAGS_QUERY_HANDSHAKE &&
706 !(status & ACPI_EC_FLAG_SCI) &&
707 (t->command == ACPI_EC_COMMAND_QUERY)) {
708 ec_transaction_transition(ec, ACPI_EC_COMMAND_POLL);
709 t->rdata[t->ri++] = 0x00;
710 ec_transaction_transition(ec, ACPI_EC_COMMAND_COMPLETE);
711 ec_dbg_evt("Command(%s) completed by software",
712 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY));
713 wakeup = true;
714 } else if ((status & ACPI_EC_FLAG_IBF) == 0) {
715 acpi_ec_write_cmd(ec, t->command);
716 ec_transaction_transition(ec, ACPI_EC_COMMAND_POLL);
717 } else
718 goto err;
719 goto out;
720 }
721err:
722 /*
723 * If SCI bit is set, then don't think it's a false IRQ
724 * otherwise will take a not handled IRQ as a false one.
725 */
726 if (!(status & ACPI_EC_FLAG_SCI)) {
727 if (in_interrupt() && t) {
728 if (t->irq_count < ec_storm_threshold)
729 ++t->irq_count;
730 /* Allow triggering on 0 threshold */
731 if (t->irq_count == ec_storm_threshold)
732 acpi_ec_mask_gpe(ec);
733 }
734 }
735out:
736 if (status & ACPI_EC_FLAG_SCI)
737 acpi_ec_submit_query(ec);
738 if (wakeup && in_interrupt())
739 wake_up(&ec->wait);
740}
741
742static void start_transaction(struct acpi_ec *ec)
743{
744 ec->curr->irq_count = ec->curr->wi = ec->curr->ri = 0;
745 ec->curr->flags = 0;
746}
747
748static int ec_guard(struct acpi_ec *ec)
749{
750 unsigned long guard = usecs_to_jiffies(ec->polling_guard);
751 unsigned long timeout = ec->timestamp + guard;
752
753 /* Ensure guarding period before polling EC status */
754 do {
755 if (ec->busy_polling) {
756 /* Perform busy polling */
757 if (ec_transaction_completed(ec))
758 return 0;
759 udelay(jiffies_to_usecs(guard));
760 } else {
761 /*
762 * Perform wait polling
763 * 1. Wait the transaction to be completed by the
764 * GPE handler after the transaction enters
765 * ACPI_EC_COMMAND_POLL state.
766 * 2. A special guarding logic is also required
767 * for event clearing mode "event" before the
768 * transaction enters ACPI_EC_COMMAND_POLL
769 * state.
770 */
771 if (!ec_transaction_polled(ec) &&
772 !acpi_ec_guard_event(ec))
773 break;
774 if (wait_event_timeout(ec->wait,
775 ec_transaction_completed(ec),
776 guard))
777 return 0;
778 }
779 } while (time_before(jiffies, timeout));
780 return -ETIME;
781}
782
783static int ec_poll(struct acpi_ec *ec)
784{
785 unsigned long flags;
786 int repeat = 5; /* number of command restarts */
787
788 while (repeat--) {
789 unsigned long delay = jiffies +
790 msecs_to_jiffies(ec_delay);
791 do {
792 if (!ec_guard(ec))
793 return 0;
794 spin_lock_irqsave(&ec->lock, flags);
795 advance_transaction(ec);
796 spin_unlock_irqrestore(&ec->lock, flags);
797 } while (time_before(jiffies, delay));
798 pr_debug("controller reset, restart transaction\n");
799 spin_lock_irqsave(&ec->lock, flags);
800 start_transaction(ec);
801 spin_unlock_irqrestore(&ec->lock, flags);
802 }
803 return -ETIME;
804}
805
806static int acpi_ec_transaction_unlocked(struct acpi_ec *ec,
807 struct transaction *t)
808{
809 unsigned long tmp;
810 int ret = 0;
811
812 /* start transaction */
813 spin_lock_irqsave(&ec->lock, tmp);
814 /* Enable GPE for command processing (IBF=0/OBF=1) */
815 if (!acpi_ec_submit_flushable_request(ec)) {
816 ret = -EINVAL;
817 goto unlock;
818 }
819 ec_dbg_ref(ec, "Increase command");
820 /* following two actions should be kept atomic */
821 ec->curr = t;
822 ec_dbg_req("Command(%s) started", acpi_ec_cmd_string(t->command));
823 start_transaction(ec);
824 spin_unlock_irqrestore(&ec->lock, tmp);
825
826 ret = ec_poll(ec);
827
828 spin_lock_irqsave(&ec->lock, tmp);
829 if (t->irq_count == ec_storm_threshold)
830 acpi_ec_unmask_gpe(ec);
831 ec_dbg_req("Command(%s) stopped", acpi_ec_cmd_string(t->command));
832 ec->curr = NULL;
833 /* Disable GPE for command processing (IBF=0/OBF=1) */
834 acpi_ec_complete_request(ec);
835 ec_dbg_ref(ec, "Decrease command");
836unlock:
837 spin_unlock_irqrestore(&ec->lock, tmp);
838 return ret;
839}
840
841static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t)
842{
843 int status;
844 u32 glk;
845
846 if (!ec || (!t) || (t->wlen && !t->wdata) || (t->rlen && !t->rdata))
847 return -EINVAL;
848 if (t->rdata)
849 memset(t->rdata, 0, t->rlen);
850
851 mutex_lock(&ec->mutex);
852 if (ec->global_lock) {
853 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
854 if (ACPI_FAILURE(status)) {
855 status = -ENODEV;
856 goto unlock;
857 }
858 }
859
860 status = acpi_ec_transaction_unlocked(ec, t);
861
862 if (ec->global_lock)
863 acpi_release_global_lock(glk);
864unlock:
865 mutex_unlock(&ec->mutex);
866 return status;
867}
868
869static int acpi_ec_burst_enable(struct acpi_ec *ec)
870{
871 u8 d;
872 struct transaction t = {.command = ACPI_EC_BURST_ENABLE,
873 .wdata = NULL, .rdata = &d,
874 .wlen = 0, .rlen = 1};
875
876 return acpi_ec_transaction(ec, &t);
877}
878
879static int acpi_ec_burst_disable(struct acpi_ec *ec)
880{
881 struct transaction t = {.command = ACPI_EC_BURST_DISABLE,
882 .wdata = NULL, .rdata = NULL,
883 .wlen = 0, .rlen = 0};
884
885 return (acpi_ec_read_status(ec) & ACPI_EC_FLAG_BURST) ?
886 acpi_ec_transaction(ec, &t) : 0;
887}
888
889static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 *data)
890{
891 int result;
892 u8 d;
893 struct transaction t = {.command = ACPI_EC_COMMAND_READ,
894 .wdata = &address, .rdata = &d,
895 .wlen = 1, .rlen = 1};
896
897 result = acpi_ec_transaction(ec, &t);
898 *data = d;
899 return result;
900}
901
902static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
903{
904 u8 wdata[2] = { address, data };
905 struct transaction t = {.command = ACPI_EC_COMMAND_WRITE,
906 .wdata = wdata, .rdata = NULL,
907 .wlen = 2, .rlen = 0};
908
909 return acpi_ec_transaction(ec, &t);
910}
911
912int ec_read(u8 addr, u8 *val)
913{
914 int err;
915 u8 temp_data;
916
917 if (!first_ec)
918 return -ENODEV;
919
920 err = acpi_ec_read(first_ec, addr, &temp_data);
921
922 if (!err) {
923 *val = temp_data;
924 return 0;
925 }
926 return err;
927}
928EXPORT_SYMBOL(ec_read);
929
930int ec_write(u8 addr, u8 val)
931{
932 int err;
933
934 if (!first_ec)
935 return -ENODEV;
936
937 err = acpi_ec_write(first_ec, addr, val);
938
939 return err;
940}
941EXPORT_SYMBOL(ec_write);
942
943int ec_transaction(u8 command,
944 const u8 *wdata, unsigned wdata_len,
945 u8 *rdata, unsigned rdata_len)
946{
947 struct transaction t = {.command = command,
948 .wdata = wdata, .rdata = rdata,
949 .wlen = wdata_len, .rlen = rdata_len};
950
951 if (!first_ec)
952 return -ENODEV;
953
954 return acpi_ec_transaction(first_ec, &t);
955}
956EXPORT_SYMBOL(ec_transaction);
957
958/* Get the handle to the EC device */
959acpi_handle ec_get_handle(void)
960{
961 if (!first_ec)
962 return NULL;
963 return first_ec->handle;
964}
965EXPORT_SYMBOL(ec_get_handle);
966
967static void acpi_ec_start(struct acpi_ec *ec, bool resuming)
968{
969 unsigned long flags;
970
971 spin_lock_irqsave(&ec->lock, flags);
972 if (!test_and_set_bit(EC_FLAGS_STARTED, &ec->flags)) {
973 ec_dbg_drv("Starting EC");
974 /* Enable GPE for event processing (SCI_EVT=1) */
975 if (!resuming) {
976 acpi_ec_submit_request(ec);
977 ec_dbg_ref(ec, "Increase driver");
978 }
979 ec_log_drv("EC started");
980 }
981 spin_unlock_irqrestore(&ec->lock, flags);
982}
983
984static bool acpi_ec_stopped(struct acpi_ec *ec)
985{
986 unsigned long flags;
987 bool flushed;
988
989 spin_lock_irqsave(&ec->lock, flags);
990 flushed = acpi_ec_flushed(ec);
991 spin_unlock_irqrestore(&ec->lock, flags);
992 return flushed;
993}
994
995static void acpi_ec_stop(struct acpi_ec *ec, bool suspending)
996{
997 unsigned long flags;
998
999 spin_lock_irqsave(&ec->lock, flags);
1000 if (acpi_ec_started(ec)) {
1001 ec_dbg_drv("Stopping EC");
1002 set_bit(EC_FLAGS_STOPPED, &ec->flags);
1003 spin_unlock_irqrestore(&ec->lock, flags);
1004 wait_event(ec->wait, acpi_ec_stopped(ec));
1005 spin_lock_irqsave(&ec->lock, flags);
1006 /* Disable GPE for event processing (SCI_EVT=1) */
1007 if (!suspending) {
1008 acpi_ec_complete_request(ec);
1009 ec_dbg_ref(ec, "Decrease driver");
1010 } else if (!ec_freeze_events)
1011 __acpi_ec_disable_event(ec);
1012 clear_bit(EC_FLAGS_STARTED, &ec->flags);
1013 clear_bit(EC_FLAGS_STOPPED, &ec->flags);
1014 ec_log_drv("EC stopped");
1015 }
1016 spin_unlock_irqrestore(&ec->lock, flags);
1017}
1018
1019static void acpi_ec_enter_noirq(struct acpi_ec *ec)
1020{
1021 unsigned long flags;
1022
1023 spin_lock_irqsave(&ec->lock, flags);
1024 ec->busy_polling = true;
1025 ec->polling_guard = 0;
1026 ec_log_drv("interrupt blocked");
1027 spin_unlock_irqrestore(&ec->lock, flags);
1028}
1029
1030static void acpi_ec_leave_noirq(struct acpi_ec *ec)
1031{
1032 unsigned long flags;
1033
1034 spin_lock_irqsave(&ec->lock, flags);
1035 ec->busy_polling = ec_busy_polling;
1036 ec->polling_guard = ec_polling_guard;
1037 ec_log_drv("interrupt unblocked");
1038 spin_unlock_irqrestore(&ec->lock, flags);
1039}
1040
1041void acpi_ec_block_transactions(void)
1042{
1043 struct acpi_ec *ec = first_ec;
1044
1045 if (!ec)
1046 return;
1047
1048 mutex_lock(&ec->mutex);
1049 /* Prevent transactions from being carried out */
1050 acpi_ec_stop(ec, true);
1051 mutex_unlock(&ec->mutex);
1052}
1053
1054void acpi_ec_unblock_transactions(void)
1055{
1056 /*
1057 * Allow transactions to happen again (this function is called from
1058 * atomic context during wakeup, so we don't need to acquire the mutex).
1059 */
1060 if (first_ec)
1061 acpi_ec_start(first_ec, true);
1062}
1063
1064void acpi_ec_mark_gpe_for_wake(void)
1065{
1066 if (first_ec && !ec_no_wakeup)
1067 acpi_mark_gpe_for_wake(NULL, first_ec->gpe);
1068}
1069
1070void acpi_ec_set_gpe_wake_mask(u8 action)
1071{
1072 if (first_ec && !ec_no_wakeup)
1073 acpi_set_gpe_wake_mask(NULL, first_ec->gpe, action);
1074}
1075
1076void acpi_ec_dispatch_gpe(void)
1077{
1078 if (first_ec)
1079 acpi_dispatch_gpe(NULL, first_ec->gpe);
1080}
1081
1082/* --------------------------------------------------------------------------
1083 Event Management
1084 -------------------------------------------------------------------------- */
1085static struct acpi_ec_query_handler *
1086acpi_ec_get_query_handler(struct acpi_ec_query_handler *handler)
1087{
1088 if (handler)
1089 kref_get(&handler->kref);
1090 return handler;
1091}
1092
1093static struct acpi_ec_query_handler *
1094acpi_ec_get_query_handler_by_value(struct acpi_ec *ec, u8 value)
1095{
1096 struct acpi_ec_query_handler *handler;
1097 bool found = false;
1098
1099 mutex_lock(&ec->mutex);
1100 list_for_each_entry(handler, &ec->list, node) {
1101 if (value == handler->query_bit) {
1102 found = true;
1103 break;
1104 }
1105 }
1106 mutex_unlock(&ec->mutex);
1107 return found ? acpi_ec_get_query_handler(handler) : NULL;
1108}
1109
1110static void acpi_ec_query_handler_release(struct kref *kref)
1111{
1112 struct acpi_ec_query_handler *handler =
1113 container_of(kref, struct acpi_ec_query_handler, kref);
1114
1115 kfree(handler);
1116}
1117
1118static void acpi_ec_put_query_handler(struct acpi_ec_query_handler *handler)
1119{
1120 kref_put(&handler->kref, acpi_ec_query_handler_release);
1121}
1122
1123int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
1124 acpi_handle handle, acpi_ec_query_func func,
1125 void *data)
1126{
1127 struct acpi_ec_query_handler *handler =
1128 kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL);
1129
1130 if (!handler)
1131 return -ENOMEM;
1132
1133 handler->query_bit = query_bit;
1134 handler->handle = handle;
1135 handler->func = func;
1136 handler->data = data;
1137 mutex_lock(&ec->mutex);
1138 kref_init(&handler->kref);
1139 list_add(&handler->node, &ec->list);
1140 mutex_unlock(&ec->mutex);
1141 return 0;
1142}
1143EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler);
1144
1145static void acpi_ec_remove_query_handlers(struct acpi_ec *ec,
1146 bool remove_all, u8 query_bit)
1147{
1148 struct acpi_ec_query_handler *handler, *tmp;
1149 LIST_HEAD(free_list);
1150
1151 mutex_lock(&ec->mutex);
1152 list_for_each_entry_safe(handler, tmp, &ec->list, node) {
1153 if (remove_all || query_bit == handler->query_bit) {
1154 list_del_init(&handler->node);
1155 list_add(&handler->node, &free_list);
1156 }
1157 }
1158 mutex_unlock(&ec->mutex);
1159 list_for_each_entry_safe(handler, tmp, &free_list, node)
1160 acpi_ec_put_query_handler(handler);
1161}
1162
1163void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit)
1164{
1165 acpi_ec_remove_query_handlers(ec, false, query_bit);
1166}
1167EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler);
1168
1169static struct acpi_ec_query *acpi_ec_create_query(u8 *pval)
1170{
1171 struct acpi_ec_query *q;
1172 struct transaction *t;
1173
1174 q = kzalloc(sizeof (struct acpi_ec_query), GFP_KERNEL);
1175 if (!q)
1176 return NULL;
1177 INIT_WORK(&q->work, acpi_ec_event_processor);
1178 t = &q->transaction;
1179 t->command = ACPI_EC_COMMAND_QUERY;
1180 t->rdata = pval;
1181 t->rlen = 1;
1182 return q;
1183}
1184
1185static void acpi_ec_delete_query(struct acpi_ec_query *q)
1186{
1187 if (q) {
1188 if (q->handler)
1189 acpi_ec_put_query_handler(q->handler);
1190 kfree(q);
1191 }
1192}
1193
1194static void acpi_ec_event_processor(struct work_struct *work)
1195{
1196 struct acpi_ec_query *q = container_of(work, struct acpi_ec_query, work);
1197 struct acpi_ec_query_handler *handler = q->handler;
1198
1199 ec_dbg_evt("Query(0x%02x) started", handler->query_bit);
1200 if (handler->func)
1201 handler->func(handler->data);
1202 else if (handler->handle)
1203 acpi_evaluate_object(handler->handle, NULL, NULL, NULL);
1204 ec_dbg_evt("Query(0x%02x) stopped", handler->query_bit);
1205 acpi_ec_delete_query(q);
1206}
1207
1208static int acpi_ec_query(struct acpi_ec *ec, u8 *data)
1209{
1210 u8 value = 0;
1211 int result;
1212 struct acpi_ec_query *q;
1213
1214 q = acpi_ec_create_query(&value);
1215 if (!q)
1216 return -ENOMEM;
1217
1218 /*
1219 * Query the EC to find out which _Qxx method we need to evaluate.
1220 * Note that successful completion of the query causes the ACPI_EC_SCI
1221 * bit to be cleared (and thus clearing the interrupt source).
1222 */
1223 result = acpi_ec_transaction(ec, &q->transaction);
1224 if (!value)
1225 result = -ENODATA;
1226 if (result)
1227 goto err_exit;
1228
1229 q->handler = acpi_ec_get_query_handler_by_value(ec, value);
1230 if (!q->handler) {
1231 result = -ENODATA;
1232 goto err_exit;
1233 }
1234
1235 /*
1236 * It is reported that _Qxx are evaluated in a parallel way on
1237 * Windows:
1238 * https://bugzilla.kernel.org/show_bug.cgi?id=94411
1239 *
1240 * Put this log entry before schedule_work() in order to make
1241 * it appearing before any other log entries occurred during the
1242 * work queue execution.
1243 */
1244 ec_dbg_evt("Query(0x%02x) scheduled", value);
1245 if (!queue_work(ec_query_wq, &q->work)) {
1246 ec_dbg_evt("Query(0x%02x) overlapped", value);
1247 result = -EBUSY;
1248 }
1249
1250err_exit:
1251 if (result)
1252 acpi_ec_delete_query(q);
1253 if (data)
1254 *data = value;
1255 return result;
1256}
1257
1258static void acpi_ec_check_event(struct acpi_ec *ec)
1259{
1260 unsigned long flags;
1261
1262 if (ec_event_clearing == ACPI_EC_EVT_TIMING_EVENT) {
1263 if (ec_guard(ec)) {
1264 spin_lock_irqsave(&ec->lock, flags);
1265 /*
1266 * Take care of the SCI_EVT unless no one else is
1267 * taking care of it.
1268 */
1269 if (!ec->curr)
1270 advance_transaction(ec);
1271 spin_unlock_irqrestore(&ec->lock, flags);
1272 }
1273 }
1274}
1275
1276static void acpi_ec_event_handler(struct work_struct *work)
1277{
1278 unsigned long flags;
1279 struct acpi_ec *ec = container_of(work, struct acpi_ec, work);
1280
1281 ec_dbg_evt("Event started");
1282
1283 spin_lock_irqsave(&ec->lock, flags);
1284 while (ec->nr_pending_queries) {
1285 spin_unlock_irqrestore(&ec->lock, flags);
1286 (void)acpi_ec_query(ec, NULL);
1287 spin_lock_irqsave(&ec->lock, flags);
1288 ec->nr_pending_queries--;
1289 /*
1290 * Before exit, make sure that this work item can be
1291 * scheduled again. There might be QR_EC failures, leaving
1292 * EC_FLAGS_QUERY_PENDING uncleared and preventing this work
1293 * item from being scheduled again.
1294 */
1295 if (!ec->nr_pending_queries) {
1296 if (ec_event_clearing == ACPI_EC_EVT_TIMING_STATUS ||
1297 ec_event_clearing == ACPI_EC_EVT_TIMING_QUERY)
1298 acpi_ec_complete_query(ec);
1299 }
1300 }
1301 spin_unlock_irqrestore(&ec->lock, flags);
1302
1303 ec_dbg_evt("Event stopped");
1304
1305 acpi_ec_check_event(ec);
1306}
1307
1308static u32 acpi_ec_gpe_handler(acpi_handle gpe_device,
1309 u32 gpe_number, void *data)
1310{
1311 unsigned long flags;
1312 struct acpi_ec *ec = data;
1313
1314 spin_lock_irqsave(&ec->lock, flags);
1315 advance_transaction(ec);
1316 spin_unlock_irqrestore(&ec->lock, flags);
1317 return ACPI_INTERRUPT_HANDLED;
1318}
1319
1320/* --------------------------------------------------------------------------
1321 * Address Space Management
1322 * -------------------------------------------------------------------------- */
1323
1324static acpi_status
1325acpi_ec_space_handler(u32 function, acpi_physical_address address,
1326 u32 bits, u64 *value64,
1327 void *handler_context, void *region_context)
1328{
1329 struct acpi_ec *ec = handler_context;
1330 int result = 0, i, bytes = bits / 8;
1331 u8 *value = (u8 *)value64;
1332
1333 if ((address > 0xFF) || !value || !handler_context)
1334 return AE_BAD_PARAMETER;
1335
1336 if (function != ACPI_READ && function != ACPI_WRITE)
1337 return AE_BAD_PARAMETER;
1338
1339 if (ec->busy_polling || bits > 8)
1340 acpi_ec_burst_enable(ec);
1341
1342 for (i = 0; i < bytes; ++i, ++address, ++value)
1343 result = (function == ACPI_READ) ?
1344 acpi_ec_read(ec, address, value) :
1345 acpi_ec_write(ec, address, *value);
1346
1347 if (ec->busy_polling || bits > 8)
1348 acpi_ec_burst_disable(ec);
1349
1350 switch (result) {
1351 case -EINVAL:
1352 return AE_BAD_PARAMETER;
1353 case -ENODEV:
1354 return AE_NOT_FOUND;
1355 case -ETIME:
1356 return AE_TIME;
1357 default:
1358 return AE_OK;
1359 }
1360}
1361
1362/* --------------------------------------------------------------------------
1363 * Driver Interface
1364 * -------------------------------------------------------------------------- */
1365
1366static acpi_status
1367ec_parse_io_ports(struct acpi_resource *resource, void *context);
1368
1369static void acpi_ec_free(struct acpi_ec *ec)
1370{
1371 if (first_ec == ec)
1372 first_ec = NULL;
1373 if (boot_ec == ec)
1374 boot_ec = NULL;
1375 kfree(ec);
1376}
1377
1378static struct acpi_ec *acpi_ec_alloc(void)
1379{
1380 struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
1381
1382 if (!ec)
1383 return NULL;
1384 mutex_init(&ec->mutex);
1385 init_waitqueue_head(&ec->wait);
1386 INIT_LIST_HEAD(&ec->list);
1387 spin_lock_init(&ec->lock);
1388 INIT_WORK(&ec->work, acpi_ec_event_handler);
1389 ec->timestamp = jiffies;
1390 ec->busy_polling = true;
1391 ec->polling_guard = 0;
1392 return ec;
1393}
1394
1395static acpi_status
1396acpi_ec_register_query_methods(acpi_handle handle, u32 level,
1397 void *context, void **return_value)
1398{
1399 char node_name[5];
1400 struct acpi_buffer buffer = { sizeof(node_name), node_name };
1401 struct acpi_ec *ec = context;
1402 int value = 0;
1403 acpi_status status;
1404
1405 status = acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
1406
1407 if (ACPI_SUCCESS(status) && sscanf(node_name, "_Q%x", &value) == 1)
1408 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL);
1409 return AE_OK;
1410}
1411
1412static acpi_status
1413ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
1414{
1415 acpi_status status;
1416 unsigned long long tmp = 0;
1417 struct acpi_ec *ec = context;
1418
1419 /* clear addr values, ec_parse_io_ports depend on it */
1420 ec->command_addr = ec->data_addr = 0;
1421
1422 status = acpi_walk_resources(handle, METHOD_NAME__CRS,
1423 ec_parse_io_ports, ec);
1424 if (ACPI_FAILURE(status))
1425 return status;
1426 if (ec->data_addr == 0 || ec->command_addr == 0)
1427 return AE_OK;
1428
1429 if (boot_ec && boot_ec_is_ecdt && EC_FLAGS_IGNORE_DSDT_GPE) {
1430 /*
1431 * Always inherit the GPE number setting from the ECDT
1432 * EC.
1433 */
1434 ec->gpe = boot_ec->gpe;
1435 } else {
1436 /* Get GPE bit assignment (EC events). */
1437 /* TODO: Add support for _GPE returning a package */
1438 status = acpi_evaluate_integer(handle, "_GPE", NULL, &tmp);
1439 if (ACPI_FAILURE(status))
1440 return status;
1441 ec->gpe = tmp;
1442 }
1443 /* Use the global lock for all EC transactions? */
1444 tmp = 0;
1445 acpi_evaluate_integer(handle, "_GLK", NULL, &tmp);
1446 ec->global_lock = tmp;
1447 ec->handle = handle;
1448 return AE_CTRL_TERMINATE;
1449}
1450
1451/*
1452 * Note: This function returns an error code only when the address space
1453 * handler is not installed, which means "not able to handle
1454 * transactions".
1455 */
1456static int ec_install_handlers(struct acpi_ec *ec, bool handle_events)
1457{
1458 acpi_status status;
1459
1460 acpi_ec_start(ec, false);
1461
1462 if (!test_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags)) {
1463 acpi_ec_enter_noirq(ec);
1464 status = acpi_install_address_space_handler(ec->handle,
1465 ACPI_ADR_SPACE_EC,
1466 &acpi_ec_space_handler,
1467 NULL, ec);
1468 if (ACPI_FAILURE(status)) {
1469 if (status == AE_NOT_FOUND) {
1470 /*
1471 * Maybe OS fails in evaluating the _REG
1472 * object. The AE_NOT_FOUND error will be
1473 * ignored and OS * continue to initialize
1474 * EC.
1475 */
1476 pr_err("Fail in evaluating the _REG object"
1477 " of EC device. Broken bios is suspected.\n");
1478 } else {
1479 acpi_ec_stop(ec, false);
1480 return -ENODEV;
1481 }
1482 }
1483 set_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags);
1484 }
1485
1486 if (!handle_events)
1487 return 0;
1488
1489 if (!test_bit(EC_FLAGS_EVT_HANDLER_INSTALLED, &ec->flags)) {
1490 /* Find and register all query methods */
1491 acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1,
1492 acpi_ec_register_query_methods,
1493 NULL, ec, NULL);
1494 set_bit(EC_FLAGS_EVT_HANDLER_INSTALLED, &ec->flags);
1495 }
1496 if (!test_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags)) {
1497 status = acpi_install_gpe_raw_handler(NULL, ec->gpe,
1498 ACPI_GPE_EDGE_TRIGGERED,
1499 &acpi_ec_gpe_handler, ec);
1500 /* This is not fatal as we can poll EC events */
1501 if (ACPI_SUCCESS(status)) {
1502 set_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags);
1503 acpi_ec_leave_noirq(ec);
1504 if (test_bit(EC_FLAGS_STARTED, &ec->flags) &&
1505 ec->reference_count >= 1)
1506 acpi_ec_enable_gpe(ec, true);
1507 }
1508 }
1509 /* EC is fully operational, allow queries */
1510 acpi_ec_enable_event(ec);
1511
1512 return 0;
1513}
1514
1515static void ec_remove_handlers(struct acpi_ec *ec)
1516{
1517 if (test_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags)) {
1518 if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle,
1519 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler)))
1520 pr_err("failed to remove space handler\n");
1521 clear_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags);
1522 }
1523
1524 /*
1525 * Stops handling the EC transactions after removing the operation
1526 * region handler. This is required because _REG(DISCONNECT)
1527 * invoked during the removal can result in new EC transactions.
1528 *
1529 * Flushes the EC requests and thus disables the GPE before
1530 * removing the GPE handler. This is required by the current ACPICA
1531 * GPE core. ACPICA GPE core will automatically disable a GPE when
1532 * it is indicated but there is no way to handle it. So the drivers
1533 * must disable the GPEs prior to removing the GPE handlers.
1534 */
1535 acpi_ec_stop(ec, false);
1536
1537 if (test_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags)) {
1538 if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe,
1539 &acpi_ec_gpe_handler)))
1540 pr_err("failed to remove gpe handler\n");
1541 clear_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags);
1542 }
1543 if (test_bit(EC_FLAGS_EVT_HANDLER_INSTALLED, &ec->flags)) {
1544 acpi_ec_remove_query_handlers(ec, true, 0);
1545 clear_bit(EC_FLAGS_EVT_HANDLER_INSTALLED, &ec->flags);
1546 }
1547}
1548
1549static int acpi_ec_setup(struct acpi_ec *ec, bool handle_events)
1550{
1551 int ret;
1552
1553 ret = ec_install_handlers(ec, handle_events);
1554 if (ret)
1555 return ret;
1556
1557 /* First EC capable of handling transactions */
1558 if (!first_ec) {
1559 first_ec = ec;
1560 acpi_handle_info(first_ec->handle, "Used as first EC\n");
1561 }
1562
1563 acpi_handle_info(ec->handle,
1564 "GPE=0x%x, EC_CMD/EC_SC=0x%lx, EC_DATA=0x%lx\n",
1565 ec->gpe, ec->command_addr, ec->data_addr);
1566 return ret;
1567}
1568
1569static bool acpi_ec_ecdt_get_handle(acpi_handle *phandle)
1570{
1571 struct acpi_table_ecdt *ecdt_ptr;
1572 acpi_status status;
1573 acpi_handle handle;
1574
1575 status = acpi_get_table(ACPI_SIG_ECDT, 1,
1576 (struct acpi_table_header **)&ecdt_ptr);
1577 if (ACPI_FAILURE(status))
1578 return false;
1579
1580 status = acpi_get_handle(NULL, ecdt_ptr->id, &handle);
1581 if (ACPI_FAILURE(status))
1582 return false;
1583
1584 *phandle = handle;
1585 return true;
1586}
1587
1588static int acpi_ec_add(struct acpi_device *device)
1589{
1590 struct acpi_ec *ec = NULL;
1591 bool dep_update = true;
1592 acpi_status status;
1593 int ret;
1594
1595 strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
1596 strcpy(acpi_device_class(device), ACPI_EC_CLASS);
1597
1598 if (!strcmp(acpi_device_hid(device), ACPI_ECDT_HID)) {
1599 boot_ec_is_ecdt = true;
1600 ec = boot_ec;
1601 dep_update = false;
1602 } else {
1603 ec = acpi_ec_alloc();
1604 if (!ec)
1605 return -ENOMEM;
1606
1607 status = ec_parse_device(device->handle, 0, ec, NULL);
1608 if (status != AE_CTRL_TERMINATE) {
1609 ret = -EINVAL;
1610 goto err_alloc;
1611 }
1612
1613 if (boot_ec && ec->command_addr == boot_ec->command_addr &&
1614 ec->data_addr == boot_ec->data_addr) {
1615 boot_ec_is_ecdt = false;
1616 /*
1617 * Trust PNP0C09 namespace location rather than
1618 * ECDT ID. But trust ECDT GPE rather than _GPE
1619 * because of ASUS quirks, so do not change
1620 * boot_ec->gpe to ec->gpe.
1621 */
1622 boot_ec->handle = ec->handle;
1623 acpi_handle_debug(ec->handle, "duplicated.\n");
1624 acpi_ec_free(ec);
1625 ec = boot_ec;
1626 }
1627 }
1628
1629 ret = acpi_ec_setup(ec, true);
1630 if (ret)
1631 goto err_query;
1632
1633 if (ec == boot_ec)
1634 acpi_handle_info(boot_ec->handle,
1635 "Boot %s EC used to handle transactions and events\n",
1636 boot_ec_is_ecdt ? "ECDT" : "DSDT");
1637
1638 device->driver_data = ec;
1639
1640 ret = !!request_region(ec->data_addr, 1, "EC data");
1641 WARN(!ret, "Could not request EC data io port 0x%lx", ec->data_addr);
1642 ret = !!request_region(ec->command_addr, 1, "EC cmd");
1643 WARN(!ret, "Could not request EC cmd io port 0x%lx", ec->command_addr);
1644
1645 if (dep_update) {
1646 /* Reprobe devices depending on the EC */
1647 acpi_walk_dep_device_list(ec->handle);
1648 }
1649 acpi_handle_debug(ec->handle, "enumerated.\n");
1650 return 0;
1651
1652err_query:
1653 if (ec != boot_ec)
1654 acpi_ec_remove_query_handlers(ec, true, 0);
1655err_alloc:
1656 if (ec != boot_ec)
1657 acpi_ec_free(ec);
1658 return ret;
1659}
1660
1661static int acpi_ec_remove(struct acpi_device *device)
1662{
1663 struct acpi_ec *ec;
1664
1665 if (!device)
1666 return -EINVAL;
1667
1668 ec = acpi_driver_data(device);
1669 release_region(ec->data_addr, 1);
1670 release_region(ec->command_addr, 1);
1671 device->driver_data = NULL;
1672 if (ec != boot_ec) {
1673 ec_remove_handlers(ec);
1674 acpi_ec_free(ec);
1675 }
1676 return 0;
1677}
1678
1679static acpi_status
1680ec_parse_io_ports(struct acpi_resource *resource, void *context)
1681{
1682 struct acpi_ec *ec = context;
1683
1684 if (resource->type != ACPI_RESOURCE_TYPE_IO)
1685 return AE_OK;
1686
1687 /*
1688 * The first address region returned is the data port, and
1689 * the second address region returned is the status/command
1690 * port.
1691 */
1692 if (ec->data_addr == 0)
1693 ec->data_addr = resource->data.io.minimum;
1694 else if (ec->command_addr == 0)
1695 ec->command_addr = resource->data.io.minimum;
1696 else
1697 return AE_CTRL_TERMINATE;
1698
1699 return AE_OK;
1700}
1701
1702static const struct acpi_device_id ec_device_ids[] = {
1703 {"PNP0C09", 0},
1704 {ACPI_ECDT_HID, 0},
1705 {"", 0},
1706};
1707
1708/*
1709 * This function is not Windows-compatible as Windows never enumerates the
1710 * namespace EC before the main ACPI device enumeration process. It is
1711 * retained for historical reason and will be deprecated in the future.
1712 */
1713void __init acpi_ec_dsdt_probe(void)
1714{
1715 struct acpi_ec *ec;
1716 acpi_status status;
1717 int ret;
1718
1719 /*
1720 * If a platform has ECDT, there is no need to proceed as the
1721 * following probe is not a part of the ACPI device enumeration,
1722 * executing _STA is not safe, and thus this probe may risk of
1723 * picking up an invalid EC device.
1724 */
1725 if (boot_ec)
1726 return;
1727
1728 ec = acpi_ec_alloc();
1729 if (!ec)
1730 return;
1731
1732 /*
1733 * At this point, the namespace is initialized, so start to find
1734 * the namespace objects.
1735 */
1736 status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device, ec, NULL);
1737 if (ACPI_FAILURE(status) || !ec->handle) {
1738 acpi_ec_free(ec);
1739 return;
1740 }
1741
1742 /*
1743 * When the DSDT EC is available, always re-configure boot EC to
1744 * have _REG evaluated. _REG can only be evaluated after the
1745 * namespace initialization.
1746 * At this point, the GPE is not fully initialized, so do not to
1747 * handle the events.
1748 */
1749 ret = acpi_ec_setup(ec, false);
1750 if (ret) {
1751 acpi_ec_free(ec);
1752 return;
1753 }
1754
1755 boot_ec = ec;
1756
1757 acpi_handle_info(ec->handle,
1758 "Boot DSDT EC used to handle transactions\n");
1759}
1760
1761/*
1762 * If the DSDT EC is not functioning, we still need to prepare a fully
1763 * functioning ECDT EC first in order to handle the events.
1764 * https://bugzilla.kernel.org/show_bug.cgi?id=115021
1765 */
1766static int __init acpi_ec_ecdt_start(void)
1767{
1768 acpi_handle handle;
1769
1770 if (!boot_ec)
1771 return -ENODEV;
1772 /* In case acpi_ec_ecdt_start() is called after acpi_ec_add() */
1773 if (!boot_ec_is_ecdt)
1774 return -ENODEV;
1775
1776 /*
1777 * At this point, the namespace and the GPE is initialized, so
1778 * start to find the namespace objects and handle the events.
1779 *
1780 * Note: ec->handle can be valid if this function is called after
1781 * acpi_ec_add(), hence the fast path.
1782 */
1783 if (boot_ec->handle == ACPI_ROOT_OBJECT) {
1784 if (!acpi_ec_ecdt_get_handle(&handle))
1785 return -ENODEV;
1786 boot_ec->handle = handle;
1787 }
1788
1789 /* Register to ACPI bus with PM ops attached */
1790 return acpi_bus_register_early_device(ACPI_BUS_TYPE_ECDT_EC);
1791}
1792
1793#if 0
1794/*
1795 * Some EC firmware variations refuses to respond QR_EC when SCI_EVT is not
1796 * set, for which case, we complete the QR_EC without issuing it to the
1797 * firmware.
1798 * https://bugzilla.kernel.org/show_bug.cgi?id=82611
1799 * https://bugzilla.kernel.org/show_bug.cgi?id=97381
1800 */
1801static int ec_flag_query_handshake(const struct dmi_system_id *id)
1802{
1803 pr_debug("Detected the EC firmware requiring QR_EC issued when SCI_EVT set\n");
1804 EC_FLAGS_QUERY_HANDSHAKE = 1;
1805 return 0;
1806}
1807#endif
1808
1809/*
1810 * On some hardware it is necessary to clear events accumulated by the EC during
1811 * sleep. These ECs stop reporting GPEs until they are manually polled, if too
1812 * many events are accumulated. (e.g. Samsung Series 5/9 notebooks)
1813 *
1814 * https://bugzilla.kernel.org/show_bug.cgi?id=44161
1815 *
1816 * Ideally, the EC should also be instructed NOT to accumulate events during
1817 * sleep (which Windows seems to do somehow), but the interface to control this
1818 * behaviour is not known at this time.
1819 *
1820 * Models known to be affected are Samsung 530Uxx/535Uxx/540Uxx/550Pxx/900Xxx,
1821 * however it is very likely that other Samsung models are affected.
1822 *
1823 * On systems which don't accumulate _Q events during sleep, this extra check
1824 * should be harmless.
1825 */
1826static int ec_clear_on_resume(const struct dmi_system_id *id)
1827{
1828 pr_debug("Detected system needing EC poll on resume.\n");
1829 EC_FLAGS_CLEAR_ON_RESUME = 1;
1830 ec_event_clearing = ACPI_EC_EVT_TIMING_STATUS;
1831 return 0;
1832}
1833
1834/*
1835 * Some ECDTs contain wrong register addresses.
1836 * MSI MS-171F
1837 * https://bugzilla.kernel.org/show_bug.cgi?id=12461
1838 */
1839static int ec_correct_ecdt(const struct dmi_system_id *id)
1840{
1841 pr_debug("Detected system needing ECDT address correction.\n");
1842 EC_FLAGS_CORRECT_ECDT = 1;
1843 return 0;
1844}
1845
1846/*
1847 * Some DSDTs contain wrong GPE setting.
1848 * Asus FX502VD/VE, GL702VMK, X550VXK, X580VD
1849 * https://bugzilla.kernel.org/show_bug.cgi?id=195651
1850 */
1851static int ec_honor_ecdt_gpe(const struct dmi_system_id *id)
1852{
1853 pr_debug("Detected system needing ignore DSDT GPE setting.\n");
1854 EC_FLAGS_IGNORE_DSDT_GPE = 1;
1855 return 0;
1856}
1857
1858static const struct dmi_system_id ec_dmi_table[] __initconst = {
1859 {
1860 ec_correct_ecdt, "MSI MS-171F", {
1861 DMI_MATCH(DMI_SYS_VENDOR, "Micro-Star"),
1862 DMI_MATCH(DMI_PRODUCT_NAME, "MS-171F"),}, NULL},
1863 {
1864 ec_honor_ecdt_gpe, "ASUS FX502VD", {
1865 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
1866 DMI_MATCH(DMI_PRODUCT_NAME, "FX502VD"),}, NULL},
1867 {
1868 ec_honor_ecdt_gpe, "ASUS FX502VE", {
1869 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
1870 DMI_MATCH(DMI_PRODUCT_NAME, "FX502VE"),}, NULL},
1871 {
1872 ec_honor_ecdt_gpe, "ASUS GL702VMK", {
1873 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
1874 DMI_MATCH(DMI_PRODUCT_NAME, "GL702VMK"),}, NULL},
1875 {
1876 ec_honor_ecdt_gpe, "ASUS X550VXK", {
1877 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
1878 DMI_MATCH(DMI_PRODUCT_NAME, "X550VXK"),}, NULL},
1879 {
1880 ec_honor_ecdt_gpe, "ASUS X580VD", {
1881 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
1882 DMI_MATCH(DMI_PRODUCT_NAME, "X580VD"),}, NULL},
1883 {
1884 ec_clear_on_resume, "Samsung hardware", {
1885 DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD.")}, NULL},
1886 {},
1887};
1888
1889void __init acpi_ec_ecdt_probe(void)
1890{
1891 struct acpi_table_ecdt *ecdt_ptr;
1892 struct acpi_ec *ec;
1893 acpi_status status;
1894 int ret;
1895
1896 /* Generate a boot ec context. */
1897 dmi_check_system(ec_dmi_table);
1898 status = acpi_get_table(ACPI_SIG_ECDT, 1,
1899 (struct acpi_table_header **)&ecdt_ptr);
1900 if (ACPI_FAILURE(status))
1901 return;
1902
1903 if (!ecdt_ptr->control.address || !ecdt_ptr->data.address) {
1904 /*
1905 * Asus X50GL:
1906 * https://bugzilla.kernel.org/show_bug.cgi?id=11880
1907 */
1908 return;
1909 }
1910
1911 ec = acpi_ec_alloc();
1912 if (!ec)
1913 return;
1914
1915 if (EC_FLAGS_CORRECT_ECDT) {
1916 ec->command_addr = ecdt_ptr->data.address;
1917 ec->data_addr = ecdt_ptr->control.address;
1918 } else {
1919 ec->command_addr = ecdt_ptr->control.address;
1920 ec->data_addr = ecdt_ptr->data.address;
1921 }
1922 ec->gpe = ecdt_ptr->gpe;
1923 ec->handle = ACPI_ROOT_OBJECT;
1924
1925 /*
1926 * At this point, the namespace is not initialized, so do not find
1927 * the namespace objects, or handle the events.
1928 */
1929 ret = acpi_ec_setup(ec, false);
1930 if (ret) {
1931 acpi_ec_free(ec);
1932 return;
1933 }
1934
1935 boot_ec = ec;
1936 boot_ec_is_ecdt = true;
1937
1938 pr_info("Boot ECDT EC used to handle transactions\n");
1939}
1940
1941#ifdef CONFIG_PM_SLEEP
1942static int acpi_ec_suspend(struct device *dev)
1943{
1944 struct acpi_ec *ec =
1945 acpi_driver_data(to_acpi_device(dev));
1946
1947 if (acpi_sleep_no_ec_events() && ec_freeze_events)
1948 acpi_ec_disable_event(ec);
1949 return 0;
1950}
1951
1952static int acpi_ec_suspend_noirq(struct device *dev)
1953{
1954 struct acpi_ec *ec = acpi_driver_data(to_acpi_device(dev));
1955
1956 /*
1957 * The SCI handler doesn't run at this point, so the GPE can be
1958 * masked at the low level without side effects.
1959 */
1960 if (ec_no_wakeup && test_bit(EC_FLAGS_STARTED, &ec->flags) &&
1961 ec->reference_count >= 1)
1962 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_DISABLE);
1963
1964 if (acpi_sleep_no_ec_events())
1965 acpi_ec_enter_noirq(ec);
1966
1967 return 0;
1968}
1969
1970static int acpi_ec_resume_noirq(struct device *dev)
1971{
1972 struct acpi_ec *ec = acpi_driver_data(to_acpi_device(dev));
1973
1974 if (acpi_sleep_no_ec_events())
1975 acpi_ec_leave_noirq(ec);
1976
1977 if (ec_no_wakeup && test_bit(EC_FLAGS_STARTED, &ec->flags) &&
1978 ec->reference_count >= 1)
1979 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_ENABLE);
1980
1981 return 0;
1982}
1983
1984static int acpi_ec_resume(struct device *dev)
1985{
1986 struct acpi_ec *ec =
1987 acpi_driver_data(to_acpi_device(dev));
1988
1989 acpi_ec_enable_event(ec);
1990 return 0;
1991}
1992#endif
1993
1994static const struct dev_pm_ops acpi_ec_pm = {
1995 SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(acpi_ec_suspend_noirq, acpi_ec_resume_noirq)
1996 SET_SYSTEM_SLEEP_PM_OPS(acpi_ec_suspend, acpi_ec_resume)
1997};
1998
1999static int param_set_event_clearing(const char *val,
2000 const struct kernel_param *kp)
2001{
2002 int result = 0;
2003
2004 if (!strncmp(val, "status", sizeof("status") - 1)) {
2005 ec_event_clearing = ACPI_EC_EVT_TIMING_STATUS;
2006 pr_info("Assuming SCI_EVT clearing on EC_SC accesses\n");
2007 } else if (!strncmp(val, "query", sizeof("query") - 1)) {
2008 ec_event_clearing = ACPI_EC_EVT_TIMING_QUERY;
2009 pr_info("Assuming SCI_EVT clearing on QR_EC writes\n");
2010 } else if (!strncmp(val, "event", sizeof("event") - 1)) {
2011 ec_event_clearing = ACPI_EC_EVT_TIMING_EVENT;
2012 pr_info("Assuming SCI_EVT clearing on event reads\n");
2013 } else
2014 result = -EINVAL;
2015 return result;
2016}
2017
2018static int param_get_event_clearing(char *buffer,
2019 const struct kernel_param *kp)
2020{
2021 switch (ec_event_clearing) {
2022 case ACPI_EC_EVT_TIMING_STATUS:
2023 return sprintf(buffer, "status");
2024 case ACPI_EC_EVT_TIMING_QUERY:
2025 return sprintf(buffer, "query");
2026 case ACPI_EC_EVT_TIMING_EVENT:
2027 return sprintf(buffer, "event");
2028 default:
2029 return sprintf(buffer, "invalid");
2030 }
2031 return 0;
2032}
2033
2034module_param_call(ec_event_clearing, param_set_event_clearing, param_get_event_clearing,
2035 NULL, 0644);
2036MODULE_PARM_DESC(ec_event_clearing, "Assumed SCI_EVT clearing timing");
2037
2038static struct acpi_driver acpi_ec_driver = {
2039 .name = "ec",
2040 .class = ACPI_EC_CLASS,
2041 .ids = ec_device_ids,
2042 .ops = {
2043 .add = acpi_ec_add,
2044 .remove = acpi_ec_remove,
2045 },
2046 .drv.pm = &acpi_ec_pm,
2047};
2048
2049static inline int acpi_ec_query_init(void)
2050{
2051 if (!ec_query_wq) {
2052 ec_query_wq = alloc_workqueue("kec_query", 0,
2053 ec_max_queries);
2054 if (!ec_query_wq)
2055 return -ENODEV;
2056 }
2057 return 0;
2058}
2059
2060static inline void acpi_ec_query_exit(void)
2061{
2062 if (ec_query_wq) {
2063 destroy_workqueue(ec_query_wq);
2064 ec_query_wq = NULL;
2065 }
2066}
2067
2068static const struct dmi_system_id acpi_ec_no_wakeup[] = {
2069 {
2070 .ident = "Thinkpad X1 Carbon 6th",
2071 .matches = {
2072 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
2073 DMI_MATCH(DMI_PRODUCT_FAMILY, "Thinkpad X1 Carbon 6th"),
2074 },
2075 },
2076 {
2077 .ident = "ThinkPad X1 Carbon 6th",
2078 .matches = {
2079 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
2080 DMI_MATCH(DMI_PRODUCT_FAMILY, "ThinkPad X1 Carbon 6th"),
2081 },
2082 },
2083 {
2084 .ident = "ThinkPad X1 Yoga 3rd",
2085 .matches = {
2086 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
2087 DMI_MATCH(DMI_PRODUCT_FAMILY, "ThinkPad X1 Yoga 3rd"),
2088 },
2089 },
2090 { },
2091};
2092
2093int __init acpi_ec_init(void)
2094{
2095 int result;
2096 int ecdt_fail, dsdt_fail;
2097
2098 /* register workqueue for _Qxx evaluations */
2099 result = acpi_ec_query_init();
2100 if (result)
2101 return result;
2102
2103 /*
2104 * Disable EC wakeup on following systems to prevent periodic
2105 * wakeup from EC GPE.
2106 */
2107 if (dmi_check_system(acpi_ec_no_wakeup)) {
2108 ec_no_wakeup = true;
2109 pr_debug("Disabling EC wakeup on suspend-to-idle\n");
2110 }
2111
2112 /* Drivers must be started after acpi_ec_query_init() */
2113 dsdt_fail = acpi_bus_register_driver(&acpi_ec_driver);
2114 /*
2115 * Register ECDT to ACPI bus only when PNP0C09 probe fails. This is
2116 * useful for platforms (confirmed on ASUS X550ZE) with valid ECDT
2117 * settings but invalid DSDT settings.
2118 * https://bugzilla.kernel.org/show_bug.cgi?id=196847
2119 */
2120 ecdt_fail = acpi_ec_ecdt_start();
2121 return ecdt_fail && dsdt_fail ? -ENODEV : 0;
2122}
2123
2124/* EC driver currently not unloadable */
2125#if 0
2126static void __exit acpi_ec_exit(void)
2127{
2128
2129 acpi_bus_unregister_driver(&acpi_ec_driver);
2130 acpi_ec_query_exit();
2131}
2132#endif /* 0 */
2133