1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * ec.c - ACPI Embedded Controller Driver (v3)
4 *
5 * Copyright (C) 2001-2015 Intel Corporation
6 * Author: 2014, 2015 Lv Zheng <lv.zheng@intel.com>
7 * 2006, 2007 Alexey Starikovskiy <alexey.y.starikovskiy@intel.com>
8 * 2006 Denis Sadykov <denis.m.sadykov@intel.com>
9 * 2004 Luming Yu <luming.yu@intel.com>
10 * 2001, 2002 Andy Grover <andrew.grover@intel.com>
11 * 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
12 * Copyright (C) 2008 Alexey Starikovskiy <astarikovskiy@suse.de>
13 */
14
15/* Uncomment next line to get verbose printout */
16/* #define DEBUG */
17#define pr_fmt(fmt) "ACPI: EC: " fmt
18
19#include <linux/kernel.h>
20#include <linux/module.h>
21#include <linux/init.h>
22#include <linux/types.h>
23#include <linux/delay.h>
24#include <linux/interrupt.h>
25#include <linux/list.h>
26#include <linux/spinlock.h>
27#include <linux/slab.h>
28#include <linux/suspend.h>
29#include <linux/acpi.h>
30#include <linux/dmi.h>
31#include <asm/io.h>
32
33#include "internal.h"
34
35#define ACPI_EC_CLASS "embedded_controller"
36#define ACPI_EC_DEVICE_NAME "Embedded Controller"
37
38/* EC status register */
39#define ACPI_EC_FLAG_OBF 0x01 /* Output buffer full */
40#define ACPI_EC_FLAG_IBF 0x02 /* Input buffer full */
41#define ACPI_EC_FLAG_CMD 0x08 /* Input buffer contains a command */
42#define ACPI_EC_FLAG_BURST 0x10 /* burst mode */
43#define ACPI_EC_FLAG_SCI 0x20 /* EC-SCI occurred */
44
45/*
46 * The SCI_EVT clearing timing is not defined by the ACPI specification.
47 * This leads to lots of practical timing issues for the host EC driver.
48 * The following variations are defined (from the target EC firmware's
49 * perspective):
50 * STATUS: After indicating SCI_EVT edge triggered IRQ to the host, the
51 * target can clear SCI_EVT at any time so long as the host can see
52 * the indication by reading the status register (EC_SC). So the
53 * host should re-check SCI_EVT after the first time the SCI_EVT
54 * indication is seen, which is the same time the query request
55 * (QR_EC) is written to the command register (EC_CMD). SCI_EVT set
56 * at any later time could indicate another event. Normally such
57 * kind of EC firmware has implemented an event queue and will
58 * return 0x00 to indicate "no outstanding event".
59 * QUERY: After seeing the query request (QR_EC) written to the command
60 * register (EC_CMD) by the host and having prepared the responding
61 * event value in the data register (EC_DATA), the target can safely
62 * clear SCI_EVT because the target can confirm that the current
63 * event is being handled by the host. The host then should check
64 * SCI_EVT right after reading the event response from the data
65 * register (EC_DATA).
66 * EVENT: After seeing the event response read from the data register
67 * (EC_DATA) by the host, the target can clear SCI_EVT. As the
68 * target requires time to notice the change in the data register
69 * (EC_DATA), the host may be required to wait additional guarding
70 * time before checking the SCI_EVT again. Such guarding may not be
71 * necessary if the host is notified via another IRQ.
72 */
73#define ACPI_EC_EVT_TIMING_STATUS 0x00
74#define ACPI_EC_EVT_TIMING_QUERY 0x01
75#define ACPI_EC_EVT_TIMING_EVENT 0x02
76
77/* EC commands */
78enum ec_command {
79 ACPI_EC_COMMAND_READ = 0x80,
80 ACPI_EC_COMMAND_WRITE = 0x81,
81 ACPI_EC_BURST_ENABLE = 0x82,
82 ACPI_EC_BURST_DISABLE = 0x83,
83 ACPI_EC_COMMAND_QUERY = 0x84,
84};
85
86#define ACPI_EC_DELAY 500 /* Wait 500ms max. during EC ops */
87#define ACPI_EC_UDELAY_GLK 1000 /* Wait 1ms max. to get global lock */
88#define ACPI_EC_UDELAY_POLL 550 /* Wait 1ms for EC transaction polling */
89#define ACPI_EC_CLEAR_MAX 100 /* Maximum number of events to query
90 * when trying to clear the EC */
91#define ACPI_EC_MAX_QUERIES 16 /* Maximum number of parallel queries */
92
93enum {
94 EC_FLAGS_QUERY_ENABLED, /* Query is enabled */
95 EC_FLAGS_EVENT_HANDLER_INSTALLED, /* Event handler installed */
96 EC_FLAGS_EC_HANDLER_INSTALLED, /* OpReg handler installed */
97 EC_FLAGS_EC_REG_CALLED, /* OpReg ACPI _REG method called */
98 EC_FLAGS_QUERY_METHODS_INSTALLED, /* _Qxx handlers installed */
99 EC_FLAGS_STARTED, /* Driver is started */
100 EC_FLAGS_STOPPED, /* Driver is stopped */
101 EC_FLAGS_EVENTS_MASKED, /* Events masked */
102};
103
104#define ACPI_EC_COMMAND_POLL 0x01 /* Available for command byte */
105#define ACPI_EC_COMMAND_COMPLETE 0x02 /* Completed last byte */
106
107/* ec.c is compiled in acpi namespace so this shows up as acpi.ec_delay param */
108static unsigned int ec_delay __read_mostly = ACPI_EC_DELAY;
109module_param(ec_delay, uint, 0644);
110MODULE_PARM_DESC(ec_delay, "Timeout(ms) waited until an EC command completes");
111
112static unsigned int ec_max_queries __read_mostly = ACPI_EC_MAX_QUERIES;
113module_param(ec_max_queries, uint, 0644);
114MODULE_PARM_DESC(ec_max_queries, "Maximum parallel _Qxx evaluations");
115
116static bool ec_busy_polling __read_mostly;
117module_param(ec_busy_polling, bool, 0644);
118MODULE_PARM_DESC(ec_busy_polling, "Use busy polling to advance EC transaction");
119
120static unsigned int ec_polling_guard __read_mostly = ACPI_EC_UDELAY_POLL;
121module_param(ec_polling_guard, uint, 0644);
122MODULE_PARM_DESC(ec_polling_guard, "Guard time(us) between EC accesses in polling modes");
123
124static unsigned int ec_event_clearing __read_mostly = ACPI_EC_EVT_TIMING_QUERY;
125
126/*
127 * If the number of false interrupts per one transaction exceeds
128 * this threshold, will think there is a GPE storm happened and
129 * will disable the GPE for normal transaction.
130 */
131static unsigned int ec_storm_threshold __read_mostly = 8;
132module_param(ec_storm_threshold, uint, 0644);
133MODULE_PARM_DESC(ec_storm_threshold, "Maxim false GPE numbers not considered as GPE storm");
134
135static bool ec_freeze_events __read_mostly;
136module_param(ec_freeze_events, bool, 0644);
137MODULE_PARM_DESC(ec_freeze_events, "Disabling event handling during suspend/resume");
138
139static bool ec_no_wakeup __read_mostly;
140module_param(ec_no_wakeup, bool, 0644);
141MODULE_PARM_DESC(ec_no_wakeup, "Do not wake up from suspend-to-idle");
142
143struct acpi_ec_query_handler {
144 struct list_head node;
145 acpi_ec_query_func func;
146 acpi_handle handle;
147 void *data;
148 u8 query_bit;
149 struct kref kref;
150};
151
152struct transaction {
153 const u8 *wdata;
154 u8 *rdata;
155 unsigned short irq_count;
156 u8 command;
157 u8 wi;
158 u8 ri;
159 u8 wlen;
160 u8 rlen;
161 u8 flags;
162};
163
164struct acpi_ec_query {
165 struct transaction transaction;
166 struct work_struct work;
167 struct acpi_ec_query_handler *handler;
168 struct acpi_ec *ec;
169};
170
171static int acpi_ec_submit_query(struct acpi_ec *ec);
172static void advance_transaction(struct acpi_ec *ec, bool interrupt);
173static void acpi_ec_event_handler(struct work_struct *work);
174
175struct acpi_ec *first_ec;
176EXPORT_SYMBOL(first_ec);
177
178static struct acpi_ec *boot_ec;
179static bool boot_ec_is_ecdt;
180static struct workqueue_struct *ec_wq;
181static struct workqueue_struct *ec_query_wq;
182
183static int EC_FLAGS_CORRECT_ECDT; /* Needs ECDT port address correction */
184static int EC_FLAGS_TRUST_DSDT_GPE; /* Needs DSDT GPE as correction setting */
185static int EC_FLAGS_CLEAR_ON_RESUME; /* Needs acpi_ec_clear() on boot/resume */
186
187/* --------------------------------------------------------------------------
188 * Logging/Debugging
189 * -------------------------------------------------------------------------- */
190
191/*
192 * Splitters used by the developers to track the boundary of the EC
193 * handling processes.
194 */
195#ifdef DEBUG
196#define EC_DBG_SEP " "
197#define EC_DBG_DRV "+++++"
198#define EC_DBG_STM "====="
199#define EC_DBG_REQ "*****"
200#define EC_DBG_EVT "#####"
201#else
202#define EC_DBG_SEP ""
203#define EC_DBG_DRV
204#define EC_DBG_STM
205#define EC_DBG_REQ
206#define EC_DBG_EVT
207#endif
208
209#define ec_log_raw(fmt, ...) \
210 pr_info(fmt "\n", ##__VA_ARGS__)
211#define ec_dbg_raw(fmt, ...) \
212 pr_debug(fmt "\n", ##__VA_ARGS__)
213#define ec_log(filter, fmt, ...) \
214 ec_log_raw(filter EC_DBG_SEP fmt EC_DBG_SEP filter, ##__VA_ARGS__)
215#define ec_dbg(filter, fmt, ...) \
216 ec_dbg_raw(filter EC_DBG_SEP fmt EC_DBG_SEP filter, ##__VA_ARGS__)
217
218#define ec_log_drv(fmt, ...) \
219 ec_log(EC_DBG_DRV, fmt, ##__VA_ARGS__)
220#define ec_dbg_drv(fmt, ...) \
221 ec_dbg(EC_DBG_DRV, fmt, ##__VA_ARGS__)
222#define ec_dbg_stm(fmt, ...) \
223 ec_dbg(EC_DBG_STM, fmt, ##__VA_ARGS__)
224#define ec_dbg_req(fmt, ...) \
225 ec_dbg(EC_DBG_REQ, fmt, ##__VA_ARGS__)
226#define ec_dbg_evt(fmt, ...) \
227 ec_dbg(EC_DBG_EVT, fmt, ##__VA_ARGS__)
228#define ec_dbg_ref(ec, fmt, ...) \
229 ec_dbg_raw("%lu: " fmt, ec->reference_count, ## __VA_ARGS__)
230
231/* --------------------------------------------------------------------------
232 * Device Flags
233 * -------------------------------------------------------------------------- */
234
235static bool acpi_ec_started(struct acpi_ec *ec)
236{
237 return test_bit(EC_FLAGS_STARTED, &ec->flags) &&
238 !test_bit(EC_FLAGS_STOPPED, &ec->flags);
239}
240
241static bool acpi_ec_event_enabled(struct acpi_ec *ec)
242{
243 /*
244 * There is an OSPM early stage logic. During the early stages
245 * (boot/resume), OSPMs shouldn't enable the event handling, only
246 * the EC transactions are allowed to be performed.
247 */
248 if (!test_bit(EC_FLAGS_QUERY_ENABLED, &ec->flags))
249 return false;
250 /*
251 * However, disabling the event handling is experimental for late
252 * stage (suspend), and is controlled by the boot parameter of
253 * "ec_freeze_events":
254 * 1. true: The EC event handling is disabled before entering
255 * the noirq stage.
256 * 2. false: The EC event handling is automatically disabled as
257 * soon as the EC driver is stopped.
258 */
259 if (ec_freeze_events)
260 return acpi_ec_started(ec);
261 else
262 return test_bit(EC_FLAGS_STARTED, &ec->flags);
263}
264
265static bool acpi_ec_flushed(struct acpi_ec *ec)
266{
267 return ec->reference_count == 1;
268}
269
270/* --------------------------------------------------------------------------
271 * EC Registers
272 * -------------------------------------------------------------------------- */
273
274static inline u8 acpi_ec_read_status(struct acpi_ec *ec)
275{
276 u8 x = inb(port: ec->command_addr);
277
278 ec_dbg_raw("EC_SC(R) = 0x%2.2x "
279 "SCI_EVT=%d BURST=%d CMD=%d IBF=%d OBF=%d",
280 x,
281 !!(x & ACPI_EC_FLAG_SCI),
282 !!(x & ACPI_EC_FLAG_BURST),
283 !!(x & ACPI_EC_FLAG_CMD),
284 !!(x & ACPI_EC_FLAG_IBF),
285 !!(x & ACPI_EC_FLAG_OBF));
286 return x;
287}
288
289static inline u8 acpi_ec_read_data(struct acpi_ec *ec)
290{
291 u8 x = inb(port: ec->data_addr);
292
293 ec->timestamp = jiffies;
294 ec_dbg_raw("EC_DATA(R) = 0x%2.2x", x);
295 return x;
296}
297
298static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command)
299{
300 ec_dbg_raw("EC_SC(W) = 0x%2.2x", command);
301 outb(value: command, port: ec->command_addr);
302 ec->timestamp = jiffies;
303}
304
305static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data)
306{
307 ec_dbg_raw("EC_DATA(W) = 0x%2.2x", data);
308 outb(value: data, port: ec->data_addr);
309 ec->timestamp = jiffies;
310}
311
312#if defined(DEBUG) || defined(CONFIG_DYNAMIC_DEBUG)
313static const char *acpi_ec_cmd_string(u8 cmd)
314{
315 switch (cmd) {
316 case 0x80:
317 return "RD_EC";
318 case 0x81:
319 return "WR_EC";
320 case 0x82:
321 return "BE_EC";
322 case 0x83:
323 return "BD_EC";
324 case 0x84:
325 return "QR_EC";
326 }
327 return "UNKNOWN";
328}
329#else
330#define acpi_ec_cmd_string(cmd) "UNDEF"
331#endif
332
333/* --------------------------------------------------------------------------
334 * GPE Registers
335 * -------------------------------------------------------------------------- */
336
337static inline bool acpi_ec_gpe_status_set(struct acpi_ec *ec)
338{
339 acpi_event_status gpe_status = 0;
340
341 (void)acpi_get_gpe_status(NULL, gpe_number: ec->gpe, event_status: &gpe_status);
342 return !!(gpe_status & ACPI_EVENT_FLAG_STATUS_SET);
343}
344
345static inline void acpi_ec_enable_gpe(struct acpi_ec *ec, bool open)
346{
347 if (open)
348 acpi_enable_gpe(NULL, gpe_number: ec->gpe);
349 else {
350 BUG_ON(ec->reference_count < 1);
351 acpi_set_gpe(NULL, gpe_number: ec->gpe, ACPI_GPE_ENABLE);
352 }
353 if (acpi_ec_gpe_status_set(ec)) {
354 /*
355 * On some platforms, EN=1 writes cannot trigger GPE. So
356 * software need to manually trigger a pseudo GPE event on
357 * EN=1 writes.
358 */
359 ec_dbg_raw("Polling quirk");
360 advance_transaction(ec, interrupt: false);
361 }
362}
363
364static inline void acpi_ec_disable_gpe(struct acpi_ec *ec, bool close)
365{
366 if (close)
367 acpi_disable_gpe(NULL, gpe_number: ec->gpe);
368 else {
369 BUG_ON(ec->reference_count < 1);
370 acpi_set_gpe(NULL, gpe_number: ec->gpe, ACPI_GPE_DISABLE);
371 }
372}
373
374/* --------------------------------------------------------------------------
375 * Transaction Management
376 * -------------------------------------------------------------------------- */
377
378static void acpi_ec_submit_request(struct acpi_ec *ec)
379{
380 ec->reference_count++;
381 if (test_bit(EC_FLAGS_EVENT_HANDLER_INSTALLED, &ec->flags) &&
382 ec->gpe >= 0 && ec->reference_count == 1)
383 acpi_ec_enable_gpe(ec, open: true);
384}
385
386static void acpi_ec_complete_request(struct acpi_ec *ec)
387{
388 bool flushed = false;
389
390 ec->reference_count--;
391 if (test_bit(EC_FLAGS_EVENT_HANDLER_INSTALLED, &ec->flags) &&
392 ec->gpe >= 0 && ec->reference_count == 0)
393 acpi_ec_disable_gpe(ec, close: true);
394 flushed = acpi_ec_flushed(ec);
395 if (flushed)
396 wake_up(&ec->wait);
397}
398
399static void acpi_ec_mask_events(struct acpi_ec *ec)
400{
401 if (!test_bit(EC_FLAGS_EVENTS_MASKED, &ec->flags)) {
402 if (ec->gpe >= 0)
403 acpi_ec_disable_gpe(ec, close: false);
404 else
405 disable_irq_nosync(irq: ec->irq);
406
407 ec_dbg_drv("Polling enabled");
408 set_bit(nr: EC_FLAGS_EVENTS_MASKED, addr: &ec->flags);
409 }
410}
411
412static void acpi_ec_unmask_events(struct acpi_ec *ec)
413{
414 if (test_bit(EC_FLAGS_EVENTS_MASKED, &ec->flags)) {
415 clear_bit(nr: EC_FLAGS_EVENTS_MASKED, addr: &ec->flags);
416 if (ec->gpe >= 0)
417 acpi_ec_enable_gpe(ec, open: false);
418 else
419 enable_irq(irq: ec->irq);
420
421 ec_dbg_drv("Polling disabled");
422 }
423}
424
425/*
426 * acpi_ec_submit_flushable_request() - Increase the reference count unless
427 * the flush operation is not in
428 * progress
429 * @ec: the EC device
430 *
431 * This function must be used before taking a new action that should hold
432 * the reference count. If this function returns false, then the action
433 * must be discarded or it will prevent the flush operation from being
434 * completed.
435 */
436static bool acpi_ec_submit_flushable_request(struct acpi_ec *ec)
437{
438 if (!acpi_ec_started(ec))
439 return false;
440 acpi_ec_submit_request(ec);
441 return true;
442}
443
444static void acpi_ec_submit_event(struct acpi_ec *ec)
445{
446 /*
447 * It is safe to mask the events here, because acpi_ec_close_event()
448 * will run at least once after this.
449 */
450 acpi_ec_mask_events(ec);
451 if (!acpi_ec_event_enabled(ec))
452 return;
453
454 if (ec->event_state != EC_EVENT_READY)
455 return;
456
457 ec_dbg_evt("Command(%s) submitted/blocked",
458 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY));
459
460 ec->event_state = EC_EVENT_IN_PROGRESS;
461 /*
462 * If events_to_process is greater than 0 at this point, the while ()
463 * loop in acpi_ec_event_handler() is still running and incrementing
464 * events_to_process will cause it to invoke acpi_ec_submit_query() once
465 * more, so it is not necessary to queue up the event work to start the
466 * same loop again.
467 */
468 if (ec->events_to_process++ > 0)
469 return;
470
471 ec->events_in_progress++;
472 queue_work(wq: ec_wq, work: &ec->work);
473}
474
475static void acpi_ec_complete_event(struct acpi_ec *ec)
476{
477 if (ec->event_state == EC_EVENT_IN_PROGRESS)
478 ec->event_state = EC_EVENT_COMPLETE;
479}
480
481static void acpi_ec_close_event(struct acpi_ec *ec)
482{
483 if (ec->event_state != EC_EVENT_READY)
484 ec_dbg_evt("Command(%s) unblocked",
485 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY));
486
487 ec->event_state = EC_EVENT_READY;
488 acpi_ec_unmask_events(ec);
489}
490
491static inline void __acpi_ec_enable_event(struct acpi_ec *ec)
492{
493 if (!test_and_set_bit(nr: EC_FLAGS_QUERY_ENABLED, addr: &ec->flags))
494 ec_log_drv("event unblocked");
495 /*
496 * Unconditionally invoke this once after enabling the event
497 * handling mechanism to detect the pending events.
498 */
499 advance_transaction(ec, interrupt: false);
500}
501
502static inline void __acpi_ec_disable_event(struct acpi_ec *ec)
503{
504 if (test_and_clear_bit(nr: EC_FLAGS_QUERY_ENABLED, addr: &ec->flags))
505 ec_log_drv("event blocked");
506}
507
508/*
509 * Process _Q events that might have accumulated in the EC.
510 * Run with locked ec mutex.
511 */
512static void acpi_ec_clear(struct acpi_ec *ec)
513{
514 int i;
515
516 for (i = 0; i < ACPI_EC_CLEAR_MAX; i++) {
517 if (acpi_ec_submit_query(ec))
518 break;
519 }
520 if (unlikely(i == ACPI_EC_CLEAR_MAX))
521 pr_warn("Warning: Maximum of %d stale EC events cleared\n", i);
522 else
523 pr_info("%d stale EC events cleared\n", i);
524}
525
526static void acpi_ec_enable_event(struct acpi_ec *ec)
527{
528 unsigned long flags;
529
530 spin_lock_irqsave(&ec->lock, flags);
531 if (acpi_ec_started(ec))
532 __acpi_ec_enable_event(ec);
533 spin_unlock_irqrestore(lock: &ec->lock, flags);
534
535 /* Drain additional events if hardware requires that */
536 if (EC_FLAGS_CLEAR_ON_RESUME)
537 acpi_ec_clear(ec);
538}
539
540#ifdef CONFIG_PM_SLEEP
541static void __acpi_ec_flush_work(void)
542{
543 flush_workqueue(ec_wq); /* flush ec->work */
544 flush_workqueue(ec_query_wq); /* flush queries */
545}
546
547static void acpi_ec_disable_event(struct acpi_ec *ec)
548{
549 unsigned long flags;
550
551 spin_lock_irqsave(&ec->lock, flags);
552 __acpi_ec_disable_event(ec);
553 spin_unlock_irqrestore(lock: &ec->lock, flags);
554
555 /*
556 * When ec_freeze_events is true, we need to flush events in
557 * the proper position before entering the noirq stage.
558 */
559 __acpi_ec_flush_work();
560}
561
562void acpi_ec_flush_work(void)
563{
564 /* Without ec_wq there is nothing to flush. */
565 if (!ec_wq)
566 return;
567
568 __acpi_ec_flush_work();
569}
570#endif /* CONFIG_PM_SLEEP */
571
572static bool acpi_ec_guard_event(struct acpi_ec *ec)
573{
574 unsigned long flags;
575 bool guarded;
576
577 spin_lock_irqsave(&ec->lock, flags);
578 /*
579 * If firmware SCI_EVT clearing timing is "event", we actually
580 * don't know when the SCI_EVT will be cleared by firmware after
581 * evaluating _Qxx, so we need to re-check SCI_EVT after waiting an
582 * acceptable period.
583 *
584 * The guarding period is applicable if the event state is not
585 * EC_EVENT_READY, but otherwise if the current transaction is of the
586 * ACPI_EC_COMMAND_QUERY type, the guarding should have elapsed already
587 * and it should not be applied to let the transaction transition into
588 * the ACPI_EC_COMMAND_POLL state immediately.
589 */
590 guarded = ec_event_clearing == ACPI_EC_EVT_TIMING_EVENT &&
591 ec->event_state != EC_EVENT_READY &&
592 (!ec->curr || ec->curr->command != ACPI_EC_COMMAND_QUERY);
593 spin_unlock_irqrestore(lock: &ec->lock, flags);
594 return guarded;
595}
596
597static int ec_transaction_polled(struct acpi_ec *ec)
598{
599 unsigned long flags;
600 int ret = 0;
601
602 spin_lock_irqsave(&ec->lock, flags);
603 if (ec->curr && (ec->curr->flags & ACPI_EC_COMMAND_POLL))
604 ret = 1;
605 spin_unlock_irqrestore(lock: &ec->lock, flags);
606 return ret;
607}
608
609static int ec_transaction_completed(struct acpi_ec *ec)
610{
611 unsigned long flags;
612 int ret = 0;
613
614 spin_lock_irqsave(&ec->lock, flags);
615 if (ec->curr && (ec->curr->flags & ACPI_EC_COMMAND_COMPLETE))
616 ret = 1;
617 spin_unlock_irqrestore(lock: &ec->lock, flags);
618 return ret;
619}
620
621static inline void ec_transaction_transition(struct acpi_ec *ec, unsigned long flag)
622{
623 ec->curr->flags |= flag;
624
625 if (ec->curr->command != ACPI_EC_COMMAND_QUERY)
626 return;
627
628 switch (ec_event_clearing) {
629 case ACPI_EC_EVT_TIMING_STATUS:
630 if (flag == ACPI_EC_COMMAND_POLL)
631 acpi_ec_close_event(ec);
632
633 return;
634
635 case ACPI_EC_EVT_TIMING_QUERY:
636 if (flag == ACPI_EC_COMMAND_COMPLETE)
637 acpi_ec_close_event(ec);
638
639 return;
640
641 case ACPI_EC_EVT_TIMING_EVENT:
642 if (flag == ACPI_EC_COMMAND_COMPLETE)
643 acpi_ec_complete_event(ec);
644 }
645}
646
647static void acpi_ec_spurious_interrupt(struct acpi_ec *ec, struct transaction *t)
648{
649 if (t->irq_count < ec_storm_threshold)
650 ++t->irq_count;
651
652 /* Trigger if the threshold is 0 too. */
653 if (t->irq_count == ec_storm_threshold)
654 acpi_ec_mask_events(ec);
655}
656
657static void advance_transaction(struct acpi_ec *ec, bool interrupt)
658{
659 struct transaction *t = ec->curr;
660 bool wakeup = false;
661 u8 status;
662
663 ec_dbg_stm("%s (%d)", interrupt ? "IRQ" : "TASK", smp_processor_id());
664
665 status = acpi_ec_read_status(ec);
666
667 /*
668 * Another IRQ or a guarded polling mode advancement is detected,
669 * the next QR_EC submission is then allowed.
670 */
671 if (!t || !(t->flags & ACPI_EC_COMMAND_POLL)) {
672 if (ec_event_clearing == ACPI_EC_EVT_TIMING_EVENT &&
673 ec->event_state == EC_EVENT_COMPLETE)
674 acpi_ec_close_event(ec);
675
676 if (!t)
677 goto out;
678 }
679
680 if (t->flags & ACPI_EC_COMMAND_POLL) {
681 if (t->wlen > t->wi) {
682 if (!(status & ACPI_EC_FLAG_IBF))
683 acpi_ec_write_data(ec, data: t->wdata[t->wi++]);
684 else if (interrupt && !(status & ACPI_EC_FLAG_SCI))
685 acpi_ec_spurious_interrupt(ec, t);
686 } else if (t->rlen > t->ri) {
687 if (status & ACPI_EC_FLAG_OBF) {
688 t->rdata[t->ri++] = acpi_ec_read_data(ec);
689 if (t->rlen == t->ri) {
690 ec_transaction_transition(ec, ACPI_EC_COMMAND_COMPLETE);
691 wakeup = true;
692 if (t->command == ACPI_EC_COMMAND_QUERY)
693 ec_dbg_evt("Command(%s) completed by hardware",
694 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY));
695 }
696 } else if (interrupt && !(status & ACPI_EC_FLAG_SCI)) {
697 acpi_ec_spurious_interrupt(ec, t);
698 }
699 } else if (t->wlen == t->wi && !(status & ACPI_EC_FLAG_IBF)) {
700 ec_transaction_transition(ec, ACPI_EC_COMMAND_COMPLETE);
701 wakeup = true;
702 }
703 } else if (!(status & ACPI_EC_FLAG_IBF)) {
704 acpi_ec_write_cmd(ec, command: t->command);
705 ec_transaction_transition(ec, ACPI_EC_COMMAND_POLL);
706 }
707
708out:
709 if (status & ACPI_EC_FLAG_SCI)
710 acpi_ec_submit_event(ec);
711
712 if (wakeup && interrupt)
713 wake_up(&ec->wait);
714}
715
716static void start_transaction(struct acpi_ec *ec)
717{
718 ec->curr->irq_count = ec->curr->wi = ec->curr->ri = 0;
719 ec->curr->flags = 0;
720}
721
722static int ec_guard(struct acpi_ec *ec)
723{
724 unsigned long guard = usecs_to_jiffies(u: ec->polling_guard);
725 unsigned long timeout = ec->timestamp + guard;
726
727 /* Ensure guarding period before polling EC status */
728 do {
729 if (ec->busy_polling) {
730 /* Perform busy polling */
731 if (ec_transaction_completed(ec))
732 return 0;
733 udelay(usec: jiffies_to_usecs(j: guard));
734 } else {
735 /*
736 * Perform wait polling
737 * 1. Wait the transaction to be completed by the
738 * GPE handler after the transaction enters
739 * ACPI_EC_COMMAND_POLL state.
740 * 2. A special guarding logic is also required
741 * for event clearing mode "event" before the
742 * transaction enters ACPI_EC_COMMAND_POLL
743 * state.
744 */
745 if (!ec_transaction_polled(ec) &&
746 !acpi_ec_guard_event(ec))
747 break;
748 if (wait_event_timeout(ec->wait,
749 ec_transaction_completed(ec),
750 guard))
751 return 0;
752 }
753 } while (time_before(jiffies, timeout));
754 return -ETIME;
755}
756
757static int ec_poll(struct acpi_ec *ec)
758{
759 unsigned long flags;
760 int repeat = 5; /* number of command restarts */
761
762 while (repeat--) {
763 unsigned long delay = jiffies +
764 msecs_to_jiffies(m: ec_delay);
765 do {
766 if (!ec_guard(ec))
767 return 0;
768 spin_lock_irqsave(&ec->lock, flags);
769 advance_transaction(ec, interrupt: false);
770 spin_unlock_irqrestore(lock: &ec->lock, flags);
771 } while (time_before(jiffies, delay));
772 pr_debug("controller reset, restart transaction\n");
773 spin_lock_irqsave(&ec->lock, flags);
774 start_transaction(ec);
775 spin_unlock_irqrestore(lock: &ec->lock, flags);
776 }
777 return -ETIME;
778}
779
780static int acpi_ec_transaction_unlocked(struct acpi_ec *ec,
781 struct transaction *t)
782{
783 unsigned long tmp;
784 int ret = 0;
785
786 if (t->rdata)
787 memset(t->rdata, 0, t->rlen);
788
789 /* start transaction */
790 spin_lock_irqsave(&ec->lock, tmp);
791 /* Enable GPE for command processing (IBF=0/OBF=1) */
792 if (!acpi_ec_submit_flushable_request(ec)) {
793 ret = -EINVAL;
794 goto unlock;
795 }
796 ec_dbg_ref(ec, "Increase command");
797 /* following two actions should be kept atomic */
798 ec->curr = t;
799 ec_dbg_req("Command(%s) started", acpi_ec_cmd_string(t->command));
800 start_transaction(ec);
801 spin_unlock_irqrestore(lock: &ec->lock, flags: tmp);
802
803 ret = ec_poll(ec);
804
805 spin_lock_irqsave(&ec->lock, tmp);
806 if (t->irq_count == ec_storm_threshold)
807 acpi_ec_unmask_events(ec);
808 ec_dbg_req("Command(%s) stopped", acpi_ec_cmd_string(t->command));
809 ec->curr = NULL;
810 /* Disable GPE for command processing (IBF=0/OBF=1) */
811 acpi_ec_complete_request(ec);
812 ec_dbg_ref(ec, "Decrease command");
813unlock:
814 spin_unlock_irqrestore(lock: &ec->lock, flags: tmp);
815 return ret;
816}
817
818static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t)
819{
820 int status;
821 u32 glk;
822
823 if (!ec || (!t) || (t->wlen && !t->wdata) || (t->rlen && !t->rdata))
824 return -EINVAL;
825
826 mutex_lock(&ec->mutex);
827 if (ec->global_lock) {
828 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, handle: &glk);
829 if (ACPI_FAILURE(status)) {
830 status = -ENODEV;
831 goto unlock;
832 }
833 }
834
835 status = acpi_ec_transaction_unlocked(ec, t);
836
837 if (ec->global_lock)
838 acpi_release_global_lock(handle: glk);
839unlock:
840 mutex_unlock(lock: &ec->mutex);
841 return status;
842}
843
844static int acpi_ec_burst_enable(struct acpi_ec *ec)
845{
846 u8 d;
847 struct transaction t = {.command = ACPI_EC_BURST_ENABLE,
848 .wdata = NULL, .rdata = &d,
849 .wlen = 0, .rlen = 1};
850
851 return acpi_ec_transaction_unlocked(ec, t: &t);
852}
853
854static int acpi_ec_burst_disable(struct acpi_ec *ec)
855{
856 struct transaction t = {.command = ACPI_EC_BURST_DISABLE,
857 .wdata = NULL, .rdata = NULL,
858 .wlen = 0, .rlen = 0};
859
860 return (acpi_ec_read_status(ec) & ACPI_EC_FLAG_BURST) ?
861 acpi_ec_transaction_unlocked(ec, t: &t) : 0;
862}
863
864static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 *data)
865{
866 int result;
867 u8 d;
868 struct transaction t = {.command = ACPI_EC_COMMAND_READ,
869 .wdata = &address, .rdata = &d,
870 .wlen = 1, .rlen = 1};
871
872 result = acpi_ec_transaction(ec, t: &t);
873 *data = d;
874 return result;
875}
876
877static int acpi_ec_read_unlocked(struct acpi_ec *ec, u8 address, u8 *data)
878{
879 int result;
880 u8 d;
881 struct transaction t = {.command = ACPI_EC_COMMAND_READ,
882 .wdata = &address, .rdata = &d,
883 .wlen = 1, .rlen = 1};
884
885 result = acpi_ec_transaction_unlocked(ec, t: &t);
886 *data = d;
887 return result;
888}
889
890static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
891{
892 u8 wdata[2] = { address, data };
893 struct transaction t = {.command = ACPI_EC_COMMAND_WRITE,
894 .wdata = wdata, .rdata = NULL,
895 .wlen = 2, .rlen = 0};
896
897 return acpi_ec_transaction(ec, t: &t);
898}
899
900static int acpi_ec_write_unlocked(struct acpi_ec *ec, u8 address, u8 data)
901{
902 u8 wdata[2] = { address, data };
903 struct transaction t = {.command = ACPI_EC_COMMAND_WRITE,
904 .wdata = wdata, .rdata = NULL,
905 .wlen = 2, .rlen = 0};
906
907 return acpi_ec_transaction_unlocked(ec, t: &t);
908}
909
910int ec_read(u8 addr, u8 *val)
911{
912 int err;
913 u8 temp_data;
914
915 if (!first_ec)
916 return -ENODEV;
917
918 err = acpi_ec_read(ec: first_ec, address: addr, data: &temp_data);
919
920 if (!err) {
921 *val = temp_data;
922 return 0;
923 }
924 return err;
925}
926EXPORT_SYMBOL(ec_read);
927
928int ec_write(u8 addr, u8 val)
929{
930 if (!first_ec)
931 return -ENODEV;
932
933 return acpi_ec_write(ec: first_ec, address: addr, data: val);
934}
935EXPORT_SYMBOL(ec_write);
936
937int ec_transaction(u8 command,
938 const u8 *wdata, unsigned wdata_len,
939 u8 *rdata, unsigned rdata_len)
940{
941 struct transaction t = {.command = command,
942 .wdata = wdata, .rdata = rdata,
943 .wlen = wdata_len, .rlen = rdata_len};
944
945 if (!first_ec)
946 return -ENODEV;
947
948 return acpi_ec_transaction(ec: first_ec, t: &t);
949}
950EXPORT_SYMBOL(ec_transaction);
951
952/* Get the handle to the EC device */
953acpi_handle ec_get_handle(void)
954{
955 if (!first_ec)
956 return NULL;
957 return first_ec->handle;
958}
959EXPORT_SYMBOL(ec_get_handle);
960
961static void acpi_ec_start(struct acpi_ec *ec, bool resuming)
962{
963 unsigned long flags;
964
965 spin_lock_irqsave(&ec->lock, flags);
966 if (!test_and_set_bit(nr: EC_FLAGS_STARTED, addr: &ec->flags)) {
967 ec_dbg_drv("Starting EC");
968 /* Enable GPE for event processing (SCI_EVT=1) */
969 if (!resuming) {
970 acpi_ec_submit_request(ec);
971 ec_dbg_ref(ec, "Increase driver");
972 }
973 ec_log_drv("EC started");
974 }
975 spin_unlock_irqrestore(lock: &ec->lock, flags);
976}
977
978static bool acpi_ec_stopped(struct acpi_ec *ec)
979{
980 unsigned long flags;
981 bool flushed;
982
983 spin_lock_irqsave(&ec->lock, flags);
984 flushed = acpi_ec_flushed(ec);
985 spin_unlock_irqrestore(lock: &ec->lock, flags);
986 return flushed;
987}
988
989static void acpi_ec_stop(struct acpi_ec *ec, bool suspending)
990{
991 unsigned long flags;
992
993 spin_lock_irqsave(&ec->lock, flags);
994 if (acpi_ec_started(ec)) {
995 ec_dbg_drv("Stopping EC");
996 set_bit(nr: EC_FLAGS_STOPPED, addr: &ec->flags);
997 spin_unlock_irqrestore(lock: &ec->lock, flags);
998 wait_event(ec->wait, acpi_ec_stopped(ec));
999 spin_lock_irqsave(&ec->lock, flags);
1000 /* Disable GPE for event processing (SCI_EVT=1) */
1001 if (!suspending) {
1002 acpi_ec_complete_request(ec);
1003 ec_dbg_ref(ec, "Decrease driver");
1004 } else if (!ec_freeze_events)
1005 __acpi_ec_disable_event(ec);
1006 clear_bit(nr: EC_FLAGS_STARTED, addr: &ec->flags);
1007 clear_bit(nr: EC_FLAGS_STOPPED, addr: &ec->flags);
1008 ec_log_drv("EC stopped");
1009 }
1010 spin_unlock_irqrestore(lock: &ec->lock, flags);
1011}
1012
1013static void acpi_ec_enter_noirq(struct acpi_ec *ec)
1014{
1015 unsigned long flags;
1016
1017 spin_lock_irqsave(&ec->lock, flags);
1018 ec->busy_polling = true;
1019 ec->polling_guard = 0;
1020 ec_log_drv("interrupt blocked");
1021 spin_unlock_irqrestore(lock: &ec->lock, flags);
1022}
1023
1024static void acpi_ec_leave_noirq(struct acpi_ec *ec)
1025{
1026 unsigned long flags;
1027
1028 spin_lock_irqsave(&ec->lock, flags);
1029 ec->busy_polling = ec_busy_polling;
1030 ec->polling_guard = ec_polling_guard;
1031 ec_log_drv("interrupt unblocked");
1032 spin_unlock_irqrestore(lock: &ec->lock, flags);
1033}
1034
1035void acpi_ec_block_transactions(void)
1036{
1037 struct acpi_ec *ec = first_ec;
1038
1039 if (!ec)
1040 return;
1041
1042 mutex_lock(&ec->mutex);
1043 /* Prevent transactions from being carried out */
1044 acpi_ec_stop(ec, suspending: true);
1045 mutex_unlock(lock: &ec->mutex);
1046}
1047
1048void acpi_ec_unblock_transactions(void)
1049{
1050 /*
1051 * Allow transactions to happen again (this function is called from
1052 * atomic context during wakeup, so we don't need to acquire the mutex).
1053 */
1054 if (first_ec)
1055 acpi_ec_start(ec: first_ec, resuming: true);
1056}
1057
1058/* --------------------------------------------------------------------------
1059 Event Management
1060 -------------------------------------------------------------------------- */
1061static struct acpi_ec_query_handler *
1062acpi_ec_get_query_handler_by_value(struct acpi_ec *ec, u8 value)
1063{
1064 struct acpi_ec_query_handler *handler;
1065
1066 mutex_lock(&ec->mutex);
1067 list_for_each_entry(handler, &ec->list, node) {
1068 if (value == handler->query_bit) {
1069 kref_get(kref: &handler->kref);
1070 mutex_unlock(lock: &ec->mutex);
1071 return handler;
1072 }
1073 }
1074 mutex_unlock(lock: &ec->mutex);
1075 return NULL;
1076}
1077
1078static void acpi_ec_query_handler_release(struct kref *kref)
1079{
1080 struct acpi_ec_query_handler *handler =
1081 container_of(kref, struct acpi_ec_query_handler, kref);
1082
1083 kfree(objp: handler);
1084}
1085
1086static void acpi_ec_put_query_handler(struct acpi_ec_query_handler *handler)
1087{
1088 kref_put(kref: &handler->kref, release: acpi_ec_query_handler_release);
1089}
1090
1091int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
1092 acpi_handle handle, acpi_ec_query_func func,
1093 void *data)
1094{
1095 struct acpi_ec_query_handler *handler;
1096
1097 if (!handle && !func)
1098 return -EINVAL;
1099
1100 handler = kzalloc(sizeof(*handler), GFP_KERNEL);
1101 if (!handler)
1102 return -ENOMEM;
1103
1104 handler->query_bit = query_bit;
1105 handler->handle = handle;
1106 handler->func = func;
1107 handler->data = data;
1108 mutex_lock(&ec->mutex);
1109 kref_init(kref: &handler->kref);
1110 list_add(new: &handler->node, head: &ec->list);
1111 mutex_unlock(lock: &ec->mutex);
1112
1113 return 0;
1114}
1115EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler);
1116
1117static void acpi_ec_remove_query_handlers(struct acpi_ec *ec,
1118 bool remove_all, u8 query_bit)
1119{
1120 struct acpi_ec_query_handler *handler, *tmp;
1121 LIST_HEAD(free_list);
1122
1123 mutex_lock(&ec->mutex);
1124 list_for_each_entry_safe(handler, tmp, &ec->list, node) {
1125 /*
1126 * When remove_all is false, only remove custom query handlers
1127 * which have handler->func set. This is done to preserve query
1128 * handlers discovered thru ACPI, as they should continue handling
1129 * EC queries.
1130 */
1131 if (remove_all || (handler->func && handler->query_bit == query_bit)) {
1132 list_del_init(entry: &handler->node);
1133 list_add(new: &handler->node, head: &free_list);
1134
1135 }
1136 }
1137 mutex_unlock(lock: &ec->mutex);
1138 list_for_each_entry_safe(handler, tmp, &free_list, node)
1139 acpi_ec_put_query_handler(handler);
1140}
1141
1142void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit)
1143{
1144 acpi_ec_remove_query_handlers(ec, remove_all: false, query_bit);
1145 flush_workqueue(ec_query_wq);
1146}
1147EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler);
1148
1149static void acpi_ec_event_processor(struct work_struct *work)
1150{
1151 struct acpi_ec_query *q = container_of(work, struct acpi_ec_query, work);
1152 struct acpi_ec_query_handler *handler = q->handler;
1153 struct acpi_ec *ec = q->ec;
1154
1155 ec_dbg_evt("Query(0x%02x) started", handler->query_bit);
1156
1157 if (handler->func)
1158 handler->func(handler->data);
1159 else if (handler->handle)
1160 acpi_evaluate_object(object: handler->handle, NULL, NULL, NULL);
1161
1162 ec_dbg_evt("Query(0x%02x) stopped", handler->query_bit);
1163
1164 spin_lock_irq(lock: &ec->lock);
1165 ec->queries_in_progress--;
1166 spin_unlock_irq(lock: &ec->lock);
1167
1168 acpi_ec_put_query_handler(handler);
1169 kfree(objp: q);
1170}
1171
1172static struct acpi_ec_query *acpi_ec_create_query(struct acpi_ec *ec, u8 *pval)
1173{
1174 struct acpi_ec_query *q;
1175 struct transaction *t;
1176
1177 q = kzalloc(sizeof (struct acpi_ec_query), GFP_KERNEL);
1178 if (!q)
1179 return NULL;
1180
1181 INIT_WORK(&q->work, acpi_ec_event_processor);
1182 t = &q->transaction;
1183 t->command = ACPI_EC_COMMAND_QUERY;
1184 t->rdata = pval;
1185 t->rlen = 1;
1186 q->ec = ec;
1187 return q;
1188}
1189
1190static int acpi_ec_submit_query(struct acpi_ec *ec)
1191{
1192 struct acpi_ec_query *q;
1193 u8 value = 0;
1194 int result;
1195
1196 q = acpi_ec_create_query(ec, pval: &value);
1197 if (!q)
1198 return -ENOMEM;
1199
1200 /*
1201 * Query the EC to find out which _Qxx method we need to evaluate.
1202 * Note that successful completion of the query causes the ACPI_EC_SCI
1203 * bit to be cleared (and thus clearing the interrupt source).
1204 */
1205 result = acpi_ec_transaction(ec, t: &q->transaction);
1206 if (result)
1207 goto err_exit;
1208
1209 if (!value) {
1210 result = -ENODATA;
1211 goto err_exit;
1212 }
1213
1214 q->handler = acpi_ec_get_query_handler_by_value(ec, value);
1215 if (!q->handler) {
1216 result = -ENODATA;
1217 goto err_exit;
1218 }
1219
1220 /*
1221 * It is reported that _Qxx are evaluated in a parallel way on Windows:
1222 * https://bugzilla.kernel.org/show_bug.cgi?id=94411
1223 *
1224 * Put this log entry before queue_work() to make it appear in the log
1225 * before any other messages emitted during workqueue handling.
1226 */
1227 ec_dbg_evt("Query(0x%02x) scheduled", value);
1228
1229 spin_lock_irq(lock: &ec->lock);
1230
1231 ec->queries_in_progress++;
1232 queue_work(wq: ec_query_wq, work: &q->work);
1233
1234 spin_unlock_irq(lock: &ec->lock);
1235
1236 return 0;
1237
1238err_exit:
1239 kfree(objp: q);
1240
1241 return result;
1242}
1243
1244static void acpi_ec_event_handler(struct work_struct *work)
1245{
1246 struct acpi_ec *ec = container_of(work, struct acpi_ec, work);
1247
1248 ec_dbg_evt("Event started");
1249
1250 spin_lock_irq(lock: &ec->lock);
1251
1252 while (ec->events_to_process) {
1253 spin_unlock_irq(lock: &ec->lock);
1254
1255 acpi_ec_submit_query(ec);
1256
1257 spin_lock_irq(lock: &ec->lock);
1258
1259 ec->events_to_process--;
1260 }
1261
1262 /*
1263 * Before exit, make sure that the it will be possible to queue up the
1264 * event handling work again regardless of whether or not the query
1265 * queued up above is processed successfully.
1266 */
1267 if (ec_event_clearing == ACPI_EC_EVT_TIMING_EVENT) {
1268 bool guard_timeout;
1269
1270 acpi_ec_complete_event(ec);
1271
1272 ec_dbg_evt("Event stopped");
1273
1274 spin_unlock_irq(lock: &ec->lock);
1275
1276 guard_timeout = !!ec_guard(ec);
1277
1278 spin_lock_irq(lock: &ec->lock);
1279
1280 /* Take care of SCI_EVT unless someone else is doing that. */
1281 if (guard_timeout && !ec->curr)
1282 advance_transaction(ec, interrupt: false);
1283 } else {
1284 acpi_ec_close_event(ec);
1285
1286 ec_dbg_evt("Event stopped");
1287 }
1288
1289 ec->events_in_progress--;
1290
1291 spin_unlock_irq(lock: &ec->lock);
1292}
1293
1294static void clear_gpe_and_advance_transaction(struct acpi_ec *ec, bool interrupt)
1295{
1296 /*
1297 * Clear GPE_STS upfront to allow subsequent hardware GPE_STS 0->1
1298 * changes to always trigger a GPE interrupt.
1299 *
1300 * GPE STS is a W1C register, which means:
1301 *
1302 * 1. Software can clear it without worrying about clearing the other
1303 * GPEs' STS bits when the hardware sets them in parallel.
1304 *
1305 * 2. As long as software can ensure only clearing it when it is set,
1306 * hardware won't set it in parallel.
1307 */
1308 if (ec->gpe >= 0 && acpi_ec_gpe_status_set(ec))
1309 acpi_clear_gpe(NULL, gpe_number: ec->gpe);
1310
1311 advance_transaction(ec, interrupt: true);
1312}
1313
1314static void acpi_ec_handle_interrupt(struct acpi_ec *ec)
1315{
1316 unsigned long flags;
1317
1318 spin_lock_irqsave(&ec->lock, flags);
1319
1320 clear_gpe_and_advance_transaction(ec, interrupt: true);
1321
1322 spin_unlock_irqrestore(lock: &ec->lock, flags);
1323}
1324
1325static u32 acpi_ec_gpe_handler(acpi_handle gpe_device,
1326 u32 gpe_number, void *data)
1327{
1328 acpi_ec_handle_interrupt(ec: data);
1329 return ACPI_INTERRUPT_HANDLED;
1330}
1331
1332static irqreturn_t acpi_ec_irq_handler(int irq, void *data)
1333{
1334 acpi_ec_handle_interrupt(ec: data);
1335 return IRQ_HANDLED;
1336}
1337
1338/* --------------------------------------------------------------------------
1339 * Address Space Management
1340 * -------------------------------------------------------------------------- */
1341
1342static acpi_status
1343acpi_ec_space_handler(u32 function, acpi_physical_address address,
1344 u32 bits, u64 *value64,
1345 void *handler_context, void *region_context)
1346{
1347 struct acpi_ec *ec = handler_context;
1348 int result = 0, i, bytes = bits / 8;
1349 u8 *value = (u8 *)value64;
1350 u32 glk;
1351
1352 if ((address > 0xFF) || !value || !handler_context)
1353 return AE_BAD_PARAMETER;
1354
1355 if (function != ACPI_READ && function != ACPI_WRITE)
1356 return AE_BAD_PARAMETER;
1357
1358 mutex_lock(&ec->mutex);
1359
1360 if (ec->global_lock) {
1361 acpi_status status;
1362
1363 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, handle: &glk);
1364 if (ACPI_FAILURE(status)) {
1365 result = -ENODEV;
1366 goto unlock;
1367 }
1368 }
1369
1370 if (ec->busy_polling || bits > 8)
1371 acpi_ec_burst_enable(ec);
1372
1373 for (i = 0; i < bytes; ++i, ++address, ++value) {
1374 result = (function == ACPI_READ) ?
1375 acpi_ec_read_unlocked(ec, address, data: value) :
1376 acpi_ec_write_unlocked(ec, address, data: *value);
1377 if (result < 0)
1378 break;
1379 }
1380
1381 if (ec->busy_polling || bits > 8)
1382 acpi_ec_burst_disable(ec);
1383
1384 if (ec->global_lock)
1385 acpi_release_global_lock(handle: glk);
1386
1387unlock:
1388 mutex_unlock(lock: &ec->mutex);
1389
1390 switch (result) {
1391 case -EINVAL:
1392 return AE_BAD_PARAMETER;
1393 case -ENODEV:
1394 return AE_NOT_FOUND;
1395 case -ETIME:
1396 return AE_TIME;
1397 case 0:
1398 return AE_OK;
1399 default:
1400 return AE_ERROR;
1401 }
1402}
1403
1404/* --------------------------------------------------------------------------
1405 * Driver Interface
1406 * -------------------------------------------------------------------------- */
1407
1408static acpi_status
1409ec_parse_io_ports(struct acpi_resource *resource, void *context);
1410
1411static void acpi_ec_free(struct acpi_ec *ec)
1412{
1413 if (first_ec == ec)
1414 first_ec = NULL;
1415 if (boot_ec == ec)
1416 boot_ec = NULL;
1417 kfree(objp: ec);
1418}
1419
1420static struct acpi_ec *acpi_ec_alloc(void)
1421{
1422 struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
1423
1424 if (!ec)
1425 return NULL;
1426 mutex_init(&ec->mutex);
1427 init_waitqueue_head(&ec->wait);
1428 INIT_LIST_HEAD(list: &ec->list);
1429 spin_lock_init(&ec->lock);
1430 INIT_WORK(&ec->work, acpi_ec_event_handler);
1431 ec->timestamp = jiffies;
1432 ec->busy_polling = true;
1433 ec->polling_guard = 0;
1434 ec->gpe = -1;
1435 ec->irq = -1;
1436 return ec;
1437}
1438
1439static acpi_status
1440acpi_ec_register_query_methods(acpi_handle handle, u32 level,
1441 void *context, void **return_value)
1442{
1443 char node_name[5];
1444 struct acpi_buffer buffer = { sizeof(node_name), node_name };
1445 struct acpi_ec *ec = context;
1446 int value = 0;
1447 acpi_status status;
1448
1449 status = acpi_get_name(object: handle, ACPI_SINGLE_NAME, ret_path_ptr: &buffer);
1450
1451 if (ACPI_SUCCESS(status) && sscanf(node_name, "_Q%x", &value) == 1)
1452 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL);
1453 return AE_OK;
1454}
1455
1456static acpi_status
1457ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
1458{
1459 acpi_status status;
1460 unsigned long long tmp = 0;
1461 struct acpi_ec *ec = context;
1462
1463 /* clear addr values, ec_parse_io_ports depend on it */
1464 ec->command_addr = ec->data_addr = 0;
1465
1466 status = acpi_walk_resources(device: handle, METHOD_NAME__CRS,
1467 user_function: ec_parse_io_ports, context: ec);
1468 if (ACPI_FAILURE(status))
1469 return status;
1470 if (ec->data_addr == 0 || ec->command_addr == 0)
1471 return AE_OK;
1472
1473 /* Get GPE bit assignment (EC events). */
1474 /* TODO: Add support for _GPE returning a package */
1475 status = acpi_evaluate_integer(handle, pathname: "_GPE", NULL, data: &tmp);
1476 if (ACPI_SUCCESS(status))
1477 ec->gpe = tmp;
1478 /*
1479 * Errors are non-fatal, allowing for ACPI Reduced Hardware
1480 * platforms which use GpioInt instead of GPE.
1481 */
1482
1483 /* Use the global lock for all EC transactions? */
1484 tmp = 0;
1485 acpi_evaluate_integer(handle, pathname: "_GLK", NULL, data: &tmp);
1486 ec->global_lock = tmp;
1487 ec->handle = handle;
1488 return AE_CTRL_TERMINATE;
1489}
1490
1491static bool install_gpe_event_handler(struct acpi_ec *ec)
1492{
1493 acpi_status status;
1494
1495 status = acpi_install_gpe_raw_handler(NULL, gpe_number: ec->gpe,
1496 ACPI_GPE_EDGE_TRIGGERED,
1497 address: &acpi_ec_gpe_handler, context: ec);
1498 if (ACPI_FAILURE(status))
1499 return false;
1500
1501 if (test_bit(EC_FLAGS_STARTED, &ec->flags) && ec->reference_count >= 1)
1502 acpi_ec_enable_gpe(ec, open: true);
1503
1504 return true;
1505}
1506
1507static bool install_gpio_irq_event_handler(struct acpi_ec *ec)
1508{
1509 return request_threaded_irq(irq: ec->irq, NULL, thread_fn: acpi_ec_irq_handler,
1510 IRQF_SHARED | IRQF_ONESHOT, name: "ACPI EC", dev: ec) >= 0;
1511}
1512
1513/**
1514 * ec_install_handlers - Install service callbacks and register query methods.
1515 * @ec: Target EC.
1516 * @device: ACPI device object corresponding to @ec.
1517 * @call_reg: If _REG should be called to notify OpRegion availability
1518 *
1519 * Install a handler for the EC address space type unless it has been installed
1520 * already. If @device is not NULL, also look for EC query methods in the
1521 * namespace and register them, and install an event (either GPE or GPIO IRQ)
1522 * handler for the EC, if possible.
1523 *
1524 * Return:
1525 * -ENODEV if the address space handler cannot be installed, which means
1526 * "unable to handle transactions",
1527 * -EPROBE_DEFER if GPIO IRQ acquisition needs to be deferred,
1528 * or 0 (success) otherwise.
1529 */
1530static int ec_install_handlers(struct acpi_ec *ec, struct acpi_device *device,
1531 bool call_reg)
1532{
1533 acpi_status status;
1534
1535 acpi_ec_start(ec, resuming: false);
1536
1537 if (!test_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags)) {
1538 acpi_handle scope_handle = ec == first_ec ? ACPI_ROOT_OBJECT : ec->handle;
1539
1540 acpi_ec_enter_noirq(ec);
1541 status = acpi_install_address_space_handler_no_reg(device: scope_handle,
1542 ACPI_ADR_SPACE_EC,
1543 handler: &acpi_ec_space_handler,
1544 NULL, context: ec);
1545 if (ACPI_FAILURE(status)) {
1546 acpi_ec_stop(ec, suspending: false);
1547 return -ENODEV;
1548 }
1549 set_bit(nr: EC_FLAGS_EC_HANDLER_INSTALLED, addr: &ec->flags);
1550 }
1551
1552 if (call_reg && !test_bit(EC_FLAGS_EC_REG_CALLED, &ec->flags)) {
1553 acpi_execute_reg_methods(device: ec->handle, ACPI_UINT32_MAX, ACPI_ADR_SPACE_EC);
1554 set_bit(nr: EC_FLAGS_EC_REG_CALLED, addr: &ec->flags);
1555 }
1556
1557 if (!device)
1558 return 0;
1559
1560 if (ec->gpe < 0) {
1561 /* ACPI reduced hardware platforms use a GpioInt from _CRS. */
1562 int irq = acpi_dev_gpio_irq_get(adev: device, index: 0);
1563 /*
1564 * Bail out right away for deferred probing or complete the
1565 * initialization regardless of any other errors.
1566 */
1567 if (irq == -EPROBE_DEFER)
1568 return -EPROBE_DEFER;
1569 else if (irq >= 0)
1570 ec->irq = irq;
1571 }
1572
1573 if (!test_bit(EC_FLAGS_QUERY_METHODS_INSTALLED, &ec->flags)) {
1574 /* Find and register all query methods */
1575 acpi_walk_namespace(ACPI_TYPE_METHOD, start_object: ec->handle, max_depth: 1,
1576 descending_callback: acpi_ec_register_query_methods,
1577 NULL, context: ec, NULL);
1578 set_bit(nr: EC_FLAGS_QUERY_METHODS_INSTALLED, addr: &ec->flags);
1579 }
1580 if (!test_bit(EC_FLAGS_EVENT_HANDLER_INSTALLED, &ec->flags)) {
1581 bool ready = false;
1582
1583 if (ec->gpe >= 0)
1584 ready = install_gpe_event_handler(ec);
1585 else if (ec->irq >= 0)
1586 ready = install_gpio_irq_event_handler(ec);
1587
1588 if (ready) {
1589 set_bit(nr: EC_FLAGS_EVENT_HANDLER_INSTALLED, addr: &ec->flags);
1590 acpi_ec_leave_noirq(ec);
1591 }
1592 /*
1593 * Failures to install an event handler are not fatal, because
1594 * the EC can be polled for events.
1595 */
1596 }
1597 /* EC is fully operational, allow queries */
1598 acpi_ec_enable_event(ec);
1599
1600 return 0;
1601}
1602
1603static void ec_remove_handlers(struct acpi_ec *ec)
1604{
1605 acpi_handle scope_handle = ec == first_ec ? ACPI_ROOT_OBJECT : ec->handle;
1606
1607 if (test_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags)) {
1608 if (ACPI_FAILURE(acpi_remove_address_space_handler(
1609 scope_handle,
1610 ACPI_ADR_SPACE_EC,
1611 &acpi_ec_space_handler)))
1612 pr_err("failed to remove space handler\n");
1613 clear_bit(nr: EC_FLAGS_EC_HANDLER_INSTALLED, addr: &ec->flags);
1614 }
1615
1616 /*
1617 * Stops handling the EC transactions after removing the operation
1618 * region handler. This is required because _REG(DISCONNECT)
1619 * invoked during the removal can result in new EC transactions.
1620 *
1621 * Flushes the EC requests and thus disables the GPE before
1622 * removing the GPE handler. This is required by the current ACPICA
1623 * GPE core. ACPICA GPE core will automatically disable a GPE when
1624 * it is indicated but there is no way to handle it. So the drivers
1625 * must disable the GPEs prior to removing the GPE handlers.
1626 */
1627 acpi_ec_stop(ec, suspending: false);
1628
1629 if (test_bit(EC_FLAGS_EVENT_HANDLER_INSTALLED, &ec->flags)) {
1630 if (ec->gpe >= 0 &&
1631 ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe,
1632 &acpi_ec_gpe_handler)))
1633 pr_err("failed to remove gpe handler\n");
1634
1635 if (ec->irq >= 0)
1636 free_irq(ec->irq, ec);
1637
1638 clear_bit(nr: EC_FLAGS_EVENT_HANDLER_INSTALLED, addr: &ec->flags);
1639 }
1640 if (test_bit(EC_FLAGS_QUERY_METHODS_INSTALLED, &ec->flags)) {
1641 acpi_ec_remove_query_handlers(ec, remove_all: true, query_bit: 0);
1642 clear_bit(nr: EC_FLAGS_QUERY_METHODS_INSTALLED, addr: &ec->flags);
1643 }
1644}
1645
1646static int acpi_ec_setup(struct acpi_ec *ec, struct acpi_device *device, bool call_reg)
1647{
1648 int ret;
1649
1650 /* First EC capable of handling transactions */
1651 if (!first_ec)
1652 first_ec = ec;
1653
1654 ret = ec_install_handlers(ec, device, call_reg);
1655 if (ret) {
1656 if (ec == first_ec)
1657 first_ec = NULL;
1658
1659 return ret;
1660 }
1661
1662 pr_info("EC_CMD/EC_SC=0x%lx, EC_DATA=0x%lx\n", ec->command_addr,
1663 ec->data_addr);
1664
1665 if (test_bit(EC_FLAGS_EVENT_HANDLER_INSTALLED, &ec->flags)) {
1666 if (ec->gpe >= 0)
1667 pr_info("GPE=0x%x\n", ec->gpe);
1668 else
1669 pr_info("IRQ=%d\n", ec->irq);
1670 }
1671
1672 return ret;
1673}
1674
1675static int acpi_ec_add(struct acpi_device *device)
1676{
1677 struct acpi_ec *ec;
1678 int ret;
1679
1680 strscpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
1681 strscpy(acpi_device_class(device), ACPI_EC_CLASS);
1682
1683 if (boot_ec && (boot_ec->handle == device->handle ||
1684 !strcmp(acpi_device_hid(device), ACPI_ECDT_HID))) {
1685 /* Fast path: this device corresponds to the boot EC. */
1686 ec = boot_ec;
1687 } else {
1688 acpi_status status;
1689
1690 ec = acpi_ec_alloc();
1691 if (!ec)
1692 return -ENOMEM;
1693
1694 status = ec_parse_device(handle: device->handle, Level: 0, context: ec, NULL);
1695 if (status != AE_CTRL_TERMINATE) {
1696 ret = -EINVAL;
1697 goto err;
1698 }
1699
1700 if (boot_ec && ec->command_addr == boot_ec->command_addr &&
1701 ec->data_addr == boot_ec->data_addr) {
1702 /*
1703 * Trust PNP0C09 namespace location rather than ECDT ID.
1704 * But trust ECDT GPE rather than _GPE because of ASUS
1705 * quirks. So do not change boot_ec->gpe to ec->gpe,
1706 * except when the TRUST_DSDT_GPE quirk is set.
1707 */
1708 boot_ec->handle = ec->handle;
1709
1710 if (EC_FLAGS_TRUST_DSDT_GPE)
1711 boot_ec->gpe = ec->gpe;
1712
1713 acpi_handle_debug(ec->handle, "duplicated.\n");
1714 acpi_ec_free(ec);
1715 ec = boot_ec;
1716 }
1717 }
1718
1719 ret = acpi_ec_setup(ec, device, call_reg: true);
1720 if (ret)
1721 goto err;
1722
1723 if (ec == boot_ec)
1724 acpi_handle_info(boot_ec->handle,
1725 "Boot %s EC initialization complete\n",
1726 boot_ec_is_ecdt ? "ECDT" : "DSDT");
1727
1728 acpi_handle_info(ec->handle,
1729 "EC: Used to handle transactions and events\n");
1730
1731 device->driver_data = ec;
1732
1733 ret = !!request_region(ec->data_addr, 1, "EC data");
1734 WARN(!ret, "Could not request EC data io port 0x%lx", ec->data_addr);
1735 ret = !!request_region(ec->command_addr, 1, "EC cmd");
1736 WARN(!ret, "Could not request EC cmd io port 0x%lx", ec->command_addr);
1737
1738 /* Reprobe devices depending on the EC */
1739 acpi_dev_clear_dependencies(supplier: device);
1740
1741 acpi_handle_debug(ec->handle, "enumerated.\n");
1742 return 0;
1743
1744err:
1745 if (ec != boot_ec)
1746 acpi_ec_free(ec);
1747
1748 return ret;
1749}
1750
1751static void acpi_ec_remove(struct acpi_device *device)
1752{
1753 struct acpi_ec *ec;
1754
1755 if (!device)
1756 return;
1757
1758 ec = acpi_driver_data(d: device);
1759 release_region(ec->data_addr, 1);
1760 release_region(ec->command_addr, 1);
1761 device->driver_data = NULL;
1762 if (ec != boot_ec) {
1763 ec_remove_handlers(ec);
1764 acpi_ec_free(ec);
1765 }
1766}
1767
1768void acpi_ec_register_opregions(struct acpi_device *adev)
1769{
1770 if (first_ec && first_ec->handle != adev->handle)
1771 acpi_execute_reg_methods(device: adev->handle, nax_depth: 1, ACPI_ADR_SPACE_EC);
1772}
1773
1774static acpi_status
1775ec_parse_io_ports(struct acpi_resource *resource, void *context)
1776{
1777 struct acpi_ec *ec = context;
1778
1779 if (resource->type != ACPI_RESOURCE_TYPE_IO)
1780 return AE_OK;
1781
1782 /*
1783 * The first address region returned is the data port, and
1784 * the second address region returned is the status/command
1785 * port.
1786 */
1787 if (ec->data_addr == 0)
1788 ec->data_addr = resource->data.io.minimum;
1789 else if (ec->command_addr == 0)
1790 ec->command_addr = resource->data.io.minimum;
1791 else
1792 return AE_CTRL_TERMINATE;
1793
1794 return AE_OK;
1795}
1796
1797static const struct acpi_device_id ec_device_ids[] = {
1798 {"PNP0C09", 0},
1799 {ACPI_ECDT_HID, 0},
1800 {"", 0},
1801};
1802
1803/*
1804 * This function is not Windows-compatible as Windows never enumerates the
1805 * namespace EC before the main ACPI device enumeration process. It is
1806 * retained for historical reason and will be deprecated in the future.
1807 */
1808void __init acpi_ec_dsdt_probe(void)
1809{
1810 struct acpi_ec *ec;
1811 acpi_status status;
1812 int ret;
1813
1814 /*
1815 * If a platform has ECDT, there is no need to proceed as the
1816 * following probe is not a part of the ACPI device enumeration,
1817 * executing _STA is not safe, and thus this probe may risk of
1818 * picking up an invalid EC device.
1819 */
1820 if (boot_ec)
1821 return;
1822
1823 ec = acpi_ec_alloc();
1824 if (!ec)
1825 return;
1826
1827 /*
1828 * At this point, the namespace is initialized, so start to find
1829 * the namespace objects.
1830 */
1831 status = acpi_get_devices(HID: ec_device_ids[0].id, user_function: ec_parse_device, context: ec, NULL);
1832 if (ACPI_FAILURE(status) || !ec->handle) {
1833 acpi_ec_free(ec);
1834 return;
1835 }
1836
1837 /*
1838 * When the DSDT EC is available, always re-configure boot EC to
1839 * have _REG evaluated. _REG can only be evaluated after the
1840 * namespace initialization.
1841 * At this point, the GPE is not fully initialized, so do not to
1842 * handle the events.
1843 */
1844 ret = acpi_ec_setup(ec, NULL, call_reg: true);
1845 if (ret) {
1846 acpi_ec_free(ec);
1847 return;
1848 }
1849
1850 boot_ec = ec;
1851
1852 acpi_handle_info(ec->handle,
1853 "Boot DSDT EC used to handle transactions\n");
1854}
1855
1856/*
1857 * acpi_ec_ecdt_start - Finalize the boot ECDT EC initialization.
1858 *
1859 * First, look for an ACPI handle for the boot ECDT EC if acpi_ec_add() has not
1860 * found a matching object in the namespace.
1861 *
1862 * Next, in case the DSDT EC is not functioning, it is still necessary to
1863 * provide a functional ECDT EC to handle events, so add an extra device object
1864 * to represent it (see https://bugzilla.kernel.org/show_bug.cgi?id=115021).
1865 *
1866 * This is useful on platforms with valid ECDT and invalid DSDT EC settings,
1867 * like ASUS X550ZE (see https://bugzilla.kernel.org/show_bug.cgi?id=196847).
1868 */
1869static void __init acpi_ec_ecdt_start(void)
1870{
1871 struct acpi_table_ecdt *ecdt_ptr;
1872 acpi_handle handle;
1873 acpi_status status;
1874
1875 /* Bail out if a matching EC has been found in the namespace. */
1876 if (!boot_ec || boot_ec->handle != ACPI_ROOT_OBJECT)
1877 return;
1878
1879 /* Look up the object pointed to from the ECDT in the namespace. */
1880 status = acpi_get_table(ACPI_SIG_ECDT, instance: 1,
1881 out_table: (struct acpi_table_header **)&ecdt_ptr);
1882 if (ACPI_FAILURE(status))
1883 return;
1884
1885 status = acpi_get_handle(NULL, pathname: ecdt_ptr->id, ret_handle: &handle);
1886 if (ACPI_SUCCESS(status)) {
1887 boot_ec->handle = handle;
1888
1889 /* Add a special ACPI device object to represent the boot EC. */
1890 acpi_bus_register_early_device(type: ACPI_BUS_TYPE_ECDT_EC);
1891 }
1892
1893 acpi_put_table(table: (struct acpi_table_header *)ecdt_ptr);
1894}
1895
1896/*
1897 * On some hardware it is necessary to clear events accumulated by the EC during
1898 * sleep. These ECs stop reporting GPEs until they are manually polled, if too
1899 * many events are accumulated. (e.g. Samsung Series 5/9 notebooks)
1900 *
1901 * https://bugzilla.kernel.org/show_bug.cgi?id=44161
1902 *
1903 * Ideally, the EC should also be instructed NOT to accumulate events during
1904 * sleep (which Windows seems to do somehow), but the interface to control this
1905 * behaviour is not known at this time.
1906 *
1907 * Models known to be affected are Samsung 530Uxx/535Uxx/540Uxx/550Pxx/900Xxx,
1908 * however it is very likely that other Samsung models are affected.
1909 *
1910 * On systems which don't accumulate _Q events during sleep, this extra check
1911 * should be harmless.
1912 */
1913static int ec_clear_on_resume(const struct dmi_system_id *id)
1914{
1915 pr_debug("Detected system needing EC poll on resume.\n");
1916 EC_FLAGS_CLEAR_ON_RESUME = 1;
1917 ec_event_clearing = ACPI_EC_EVT_TIMING_STATUS;
1918 return 0;
1919}
1920
1921/*
1922 * Some ECDTs contain wrong register addresses.
1923 * MSI MS-171F
1924 * https://bugzilla.kernel.org/show_bug.cgi?id=12461
1925 */
1926static int ec_correct_ecdt(const struct dmi_system_id *id)
1927{
1928 pr_debug("Detected system needing ECDT address correction.\n");
1929 EC_FLAGS_CORRECT_ECDT = 1;
1930 return 0;
1931}
1932
1933/*
1934 * Some ECDTs contain wrong GPE setting, but they share the same port addresses
1935 * with DSDT EC, don't duplicate the DSDT EC with ECDT EC in this case.
1936 * https://bugzilla.kernel.org/show_bug.cgi?id=209989
1937 */
1938static int ec_honor_dsdt_gpe(const struct dmi_system_id *id)
1939{
1940 pr_debug("Detected system needing DSDT GPE setting.\n");
1941 EC_FLAGS_TRUST_DSDT_GPE = 1;
1942 return 0;
1943}
1944
1945static const struct dmi_system_id ec_dmi_table[] __initconst = {
1946 {
1947 /*
1948 * MSI MS-171F
1949 * https://bugzilla.kernel.org/show_bug.cgi?id=12461
1950 */
1951 .callback = ec_correct_ecdt,
1952 .matches = {
1953 DMI_MATCH(DMI_SYS_VENDOR, "Micro-Star"),
1954 DMI_MATCH(DMI_PRODUCT_NAME, "MS-171F"),
1955 },
1956 },
1957 {
1958 /*
1959 * HP Pavilion Gaming Laptop 15-cx0xxx
1960 * https://bugzilla.kernel.org/show_bug.cgi?id=209989
1961 */
1962 .callback = ec_honor_dsdt_gpe,
1963 .matches = {
1964 DMI_MATCH(DMI_SYS_VENDOR, "HP"),
1965 DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion Gaming Laptop 15-cx0xxx"),
1966 },
1967 },
1968 {
1969 /*
1970 * HP Pavilion Gaming Laptop 15-cx0041ur
1971 */
1972 .callback = ec_honor_dsdt_gpe,
1973 .matches = {
1974 DMI_MATCH(DMI_SYS_VENDOR, "HP"),
1975 DMI_MATCH(DMI_PRODUCT_NAME, "HP 15-cx0041ur"),
1976 },
1977 },
1978 {
1979 /*
1980 * HP Pavilion Gaming Laptop 15-dk1xxx
1981 * https://github.com/systemd/systemd/issues/28942
1982 */
1983 .callback = ec_honor_dsdt_gpe,
1984 .matches = {
1985 DMI_MATCH(DMI_SYS_VENDOR, "HP"),
1986 DMI_MATCH(DMI_PRODUCT_NAME, "HP Pavilion Gaming Laptop 15-dk1xxx"),
1987 },
1988 },
1989 {
1990 /*
1991 * HP 250 G7 Notebook PC
1992 */
1993 .callback = ec_honor_dsdt_gpe,
1994 .matches = {
1995 DMI_MATCH(DMI_SYS_VENDOR, "HP"),
1996 DMI_MATCH(DMI_PRODUCT_NAME, "HP 250 G7 Notebook PC"),
1997 },
1998 },
1999 {
2000 /*
2001 * Samsung hardware
2002 * https://bugzilla.kernel.org/show_bug.cgi?id=44161
2003 */
2004 .callback = ec_clear_on_resume,
2005 .matches = {
2006 DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD."),
2007 },
2008 },
2009 {}
2010};
2011
2012void __init acpi_ec_ecdt_probe(void)
2013{
2014 struct acpi_table_ecdt *ecdt_ptr;
2015 struct acpi_ec *ec;
2016 acpi_status status;
2017 int ret;
2018
2019 /* Generate a boot ec context. */
2020 dmi_check_system(list: ec_dmi_table);
2021 status = acpi_get_table(ACPI_SIG_ECDT, instance: 1,
2022 out_table: (struct acpi_table_header **)&ecdt_ptr);
2023 if (ACPI_FAILURE(status))
2024 return;
2025
2026 if (!ecdt_ptr->control.address || !ecdt_ptr->data.address) {
2027 /*
2028 * Asus X50GL:
2029 * https://bugzilla.kernel.org/show_bug.cgi?id=11880
2030 */
2031 goto out;
2032 }
2033
2034 ec = acpi_ec_alloc();
2035 if (!ec)
2036 goto out;
2037
2038 if (EC_FLAGS_CORRECT_ECDT) {
2039 ec->command_addr = ecdt_ptr->data.address;
2040 ec->data_addr = ecdt_ptr->control.address;
2041 } else {
2042 ec->command_addr = ecdt_ptr->control.address;
2043 ec->data_addr = ecdt_ptr->data.address;
2044 }
2045
2046 /*
2047 * Ignore the GPE value on Reduced Hardware platforms.
2048 * Some products have this set to an erroneous value.
2049 */
2050 if (!acpi_gbl_reduced_hardware)
2051 ec->gpe = ecdt_ptr->gpe;
2052
2053 ec->handle = ACPI_ROOT_OBJECT;
2054
2055 /*
2056 * At this point, the namespace is not initialized, so do not find
2057 * the namespace objects, or handle the events.
2058 */
2059 ret = acpi_ec_setup(ec, NULL, call_reg: false);
2060 if (ret) {
2061 acpi_ec_free(ec);
2062 goto out;
2063 }
2064
2065 boot_ec = ec;
2066 boot_ec_is_ecdt = true;
2067
2068 pr_info("Boot ECDT EC used to handle transactions\n");
2069
2070out:
2071 acpi_put_table(table: (struct acpi_table_header *)ecdt_ptr);
2072}
2073
2074#ifdef CONFIG_PM_SLEEP
2075static int acpi_ec_suspend(struct device *dev)
2076{
2077 struct acpi_ec *ec =
2078 acpi_driver_data(to_acpi_device(dev));
2079
2080 if (!pm_suspend_no_platform() && ec_freeze_events)
2081 acpi_ec_disable_event(ec);
2082 return 0;
2083}
2084
2085static int acpi_ec_suspend_noirq(struct device *dev)
2086{
2087 struct acpi_ec *ec = acpi_driver_data(to_acpi_device(dev));
2088
2089 /*
2090 * The SCI handler doesn't run at this point, so the GPE can be
2091 * masked at the low level without side effects.
2092 */
2093 if (ec_no_wakeup && test_bit(EC_FLAGS_STARTED, &ec->flags) &&
2094 ec->gpe >= 0 && ec->reference_count >= 1)
2095 acpi_set_gpe(NULL, gpe_number: ec->gpe, ACPI_GPE_DISABLE);
2096
2097 acpi_ec_enter_noirq(ec);
2098
2099 return 0;
2100}
2101
2102static int acpi_ec_resume_noirq(struct device *dev)
2103{
2104 struct acpi_ec *ec = acpi_driver_data(to_acpi_device(dev));
2105
2106 acpi_ec_leave_noirq(ec);
2107
2108 if (ec_no_wakeup && test_bit(EC_FLAGS_STARTED, &ec->flags) &&
2109 ec->gpe >= 0 && ec->reference_count >= 1)
2110 acpi_set_gpe(NULL, gpe_number: ec->gpe, ACPI_GPE_ENABLE);
2111
2112 return 0;
2113}
2114
2115static int acpi_ec_resume(struct device *dev)
2116{
2117 struct acpi_ec *ec =
2118 acpi_driver_data(to_acpi_device(dev));
2119
2120 acpi_ec_enable_event(ec);
2121 return 0;
2122}
2123
2124void acpi_ec_mark_gpe_for_wake(void)
2125{
2126 if (first_ec && !ec_no_wakeup)
2127 acpi_mark_gpe_for_wake(NULL, gpe_number: first_ec->gpe);
2128}
2129EXPORT_SYMBOL_GPL(acpi_ec_mark_gpe_for_wake);
2130
2131void acpi_ec_set_gpe_wake_mask(u8 action)
2132{
2133 if (pm_suspend_no_platform() && first_ec && !ec_no_wakeup)
2134 acpi_set_gpe_wake_mask(NULL, gpe_number: first_ec->gpe, action);
2135}
2136
2137static bool acpi_ec_work_in_progress(struct acpi_ec *ec)
2138{
2139 return ec->events_in_progress + ec->queries_in_progress > 0;
2140}
2141
2142bool acpi_ec_dispatch_gpe(void)
2143{
2144 bool work_in_progress = false;
2145
2146 if (!first_ec)
2147 return acpi_any_gpe_status_set(U32_MAX);
2148
2149 /*
2150 * Report wakeup if the status bit is set for any enabled GPE other
2151 * than the EC one.
2152 */
2153 if (acpi_any_gpe_status_set(gpe_skip_number: first_ec->gpe))
2154 return true;
2155
2156 /*
2157 * Cancel the SCI wakeup and process all pending events in case there
2158 * are any wakeup ones in there.
2159 *
2160 * Note that if any non-EC GPEs are active at this point, the SCI will
2161 * retrigger after the rearming in acpi_s2idle_wake(), so no events
2162 * should be missed by canceling the wakeup here.
2163 */
2164 pm_system_cancel_wakeup();
2165
2166 /*
2167 * Dispatch the EC GPE in-band, but do not report wakeup in any case
2168 * to allow the caller to process events properly after that.
2169 */
2170 spin_lock_irq(lock: &first_ec->lock);
2171
2172 if (acpi_ec_gpe_status_set(ec: first_ec)) {
2173 pm_pr_dbg("ACPI EC GPE status set\n");
2174
2175 clear_gpe_and_advance_transaction(ec: first_ec, interrupt: false);
2176 work_in_progress = acpi_ec_work_in_progress(ec: first_ec);
2177 }
2178
2179 spin_unlock_irq(lock: &first_ec->lock);
2180
2181 if (!work_in_progress)
2182 return false;
2183
2184 pm_pr_dbg("ACPI EC GPE dispatched\n");
2185
2186 /* Drain EC work. */
2187 do {
2188 acpi_ec_flush_work();
2189
2190 pm_pr_dbg("ACPI EC work flushed\n");
2191
2192 spin_lock_irq(lock: &first_ec->lock);
2193
2194 work_in_progress = acpi_ec_work_in_progress(ec: first_ec);
2195
2196 spin_unlock_irq(lock: &first_ec->lock);
2197 } while (work_in_progress && !pm_wakeup_pending());
2198
2199 return false;
2200}
2201#endif /* CONFIG_PM_SLEEP */
2202
2203static const struct dev_pm_ops acpi_ec_pm = {
2204 SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(acpi_ec_suspend_noirq, acpi_ec_resume_noirq)
2205 SET_SYSTEM_SLEEP_PM_OPS(acpi_ec_suspend, acpi_ec_resume)
2206};
2207
2208static int param_set_event_clearing(const char *val,
2209 const struct kernel_param *kp)
2210{
2211 int result = 0;
2212
2213 if (!strncmp(val, "status", sizeof("status") - 1)) {
2214 ec_event_clearing = ACPI_EC_EVT_TIMING_STATUS;
2215 pr_info("Assuming SCI_EVT clearing on EC_SC accesses\n");
2216 } else if (!strncmp(val, "query", sizeof("query") - 1)) {
2217 ec_event_clearing = ACPI_EC_EVT_TIMING_QUERY;
2218 pr_info("Assuming SCI_EVT clearing on QR_EC writes\n");
2219 } else if (!strncmp(val, "event", sizeof("event") - 1)) {
2220 ec_event_clearing = ACPI_EC_EVT_TIMING_EVENT;
2221 pr_info("Assuming SCI_EVT clearing on event reads\n");
2222 } else
2223 result = -EINVAL;
2224 return result;
2225}
2226
2227static int param_get_event_clearing(char *buffer,
2228 const struct kernel_param *kp)
2229{
2230 switch (ec_event_clearing) {
2231 case ACPI_EC_EVT_TIMING_STATUS:
2232 return sprintf(buf: buffer, fmt: "status\n");
2233 case ACPI_EC_EVT_TIMING_QUERY:
2234 return sprintf(buf: buffer, fmt: "query\n");
2235 case ACPI_EC_EVT_TIMING_EVENT:
2236 return sprintf(buf: buffer, fmt: "event\n");
2237 default:
2238 return sprintf(buf: buffer, fmt: "invalid\n");
2239 }
2240 return 0;
2241}
2242
2243module_param_call(ec_event_clearing, param_set_event_clearing, param_get_event_clearing,
2244 NULL, 0644);
2245MODULE_PARM_DESC(ec_event_clearing, "Assumed SCI_EVT clearing timing");
2246
2247static struct acpi_driver acpi_ec_driver = {
2248 .name = "ec",
2249 .class = ACPI_EC_CLASS,
2250 .ids = ec_device_ids,
2251 .ops = {
2252 .add = acpi_ec_add,
2253 .remove = acpi_ec_remove,
2254 },
2255 .drv.pm = &acpi_ec_pm,
2256};
2257
2258static void acpi_ec_destroy_workqueues(void)
2259{
2260 if (ec_wq) {
2261 destroy_workqueue(wq: ec_wq);
2262 ec_wq = NULL;
2263 }
2264 if (ec_query_wq) {
2265 destroy_workqueue(wq: ec_query_wq);
2266 ec_query_wq = NULL;
2267 }
2268}
2269
2270static int acpi_ec_init_workqueues(void)
2271{
2272 if (!ec_wq)
2273 ec_wq = alloc_ordered_workqueue("kec", 0);
2274
2275 if (!ec_query_wq)
2276 ec_query_wq = alloc_workqueue(fmt: "kec_query", flags: 0, max_active: ec_max_queries);
2277
2278 if (!ec_wq || !ec_query_wq) {
2279 acpi_ec_destroy_workqueues();
2280 return -ENODEV;
2281 }
2282 return 0;
2283}
2284
2285static const struct dmi_system_id acpi_ec_no_wakeup[] = {
2286 {
2287 .matches = {
2288 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
2289 DMI_MATCH(DMI_PRODUCT_FAMILY, "Thinkpad X1 Carbon 6th"),
2290 },
2291 },
2292 {
2293 .matches = {
2294 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
2295 DMI_MATCH(DMI_PRODUCT_FAMILY, "ThinkPad X1 Yoga 3rd"),
2296 },
2297 },
2298 {
2299 .matches = {
2300 DMI_MATCH(DMI_SYS_VENDOR, "HP"),
2301 DMI_MATCH(DMI_PRODUCT_FAMILY, "103C_5336AN HP ZHAN 66 Pro"),
2302 },
2303 },
2304 /*
2305 * Lenovo Legion Go S; touchscreen blocks HW sleep when woken up from EC
2306 * https://gitlab.freedesktop.org/drm/amd/-/issues/3929
2307 */
2308 {
2309 .matches = {
2310 DMI_MATCH(DMI_BOARD_VENDOR, "LENOVO"),
2311 DMI_MATCH(DMI_PRODUCT_NAME, "83L3"),
2312 }
2313 },
2314 {
2315 .matches = {
2316 DMI_MATCH(DMI_BOARD_VENDOR, "LENOVO"),
2317 DMI_MATCH(DMI_PRODUCT_NAME, "83N6"),
2318 }
2319 },
2320 {
2321 .matches = {
2322 DMI_MATCH(DMI_BOARD_VENDOR, "LENOVO"),
2323 DMI_MATCH(DMI_PRODUCT_NAME, "83Q2"),
2324 }
2325 },
2326 {
2327 .matches = {
2328 DMI_MATCH(DMI_BOARD_VENDOR, "LENOVO"),
2329 DMI_MATCH(DMI_PRODUCT_NAME, "83Q3"),
2330 }
2331 },
2332 {
2333 // TUXEDO InfinityBook Pro AMD Gen9
2334 .matches = {
2335 DMI_MATCH(DMI_BOARD_NAME, "GXxHRXx"),
2336 },
2337 },
2338 { },
2339};
2340
2341void __init acpi_ec_init(void)
2342{
2343 int result;
2344
2345 result = acpi_ec_init_workqueues();
2346 if (result)
2347 return;
2348
2349 /*
2350 * Disable EC wakeup on following systems to prevent periodic
2351 * wakeup from EC GPE.
2352 */
2353 if (dmi_check_system(list: acpi_ec_no_wakeup)) {
2354 ec_no_wakeup = true;
2355 pr_debug("Disabling EC wakeup on suspend-to-idle\n");
2356 }
2357
2358 /* Driver must be registered after acpi_ec_init_workqueues(). */
2359 acpi_bus_register_driver(&acpi_ec_driver);
2360
2361 acpi_ec_ecdt_start();
2362}
2363
2364/* EC driver currently not unloadable */
2365#if 0
2366static void __exit acpi_ec_exit(void)
2367{
2368
2369 acpi_bus_unregister_driver(&acpi_ec_driver);
2370 acpi_ec_destroy_workqueues();
2371}
2372#endif /* 0 */
2373

Provided by KDAB

Privacy Policy
Improve your Profiling and Debugging skills
Find out more

source code of linux/drivers/acpi/ec.c