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1/*
2 * ec.c - ACPI Embedded Controller Driver (v2.1)
3 *
4 * Copyright (C) 2006-2008 Alexey Starikovskiy <astarikovskiy@suse.de>
5 * Copyright (C) 2006 Denis Sadykov <denis.m.sadykov@intel.com>
6 * Copyright (C) 2004 Luming Yu <luming.yu@intel.com>
7 * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
8 * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
9 *
10 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
11 *
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License as published by
14 * the Free Software Foundation; either version 2 of the License, or (at
15 * your option) any later version.
16 *
17 * This program is distributed in the hope that it will be useful, but
18 * WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
20 * General Public License for more details.
21 *
22 * You should have received a copy of the GNU General Public License along
23 * with this program; if not, write to the Free Software Foundation, Inc.,
24 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
25 *
26 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
27 */
28
29/* Uncomment next line to get verbose printout */
30/* #define DEBUG */
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 <asm/io.h>
42#include <acpi/acpi_bus.h>
43#include <acpi/acpi_drivers.h>
44#include <linux/dmi.h>
45
46#include "internal.h"
47
48#define ACPI_EC_CLASS "embedded_controller"
49#define ACPI_EC_DEVICE_NAME "Embedded Controller"
50#define ACPI_EC_FILE_INFO "info"
51
52#undef PREFIX
53#define PREFIX "ACPI: EC: "
54
55/* EC status register */
56#define ACPI_EC_FLAG_OBF 0x01 /* Output buffer full */
57#define ACPI_EC_FLAG_IBF 0x02 /* Input buffer full */
58#define ACPI_EC_FLAG_BURST 0x10 /* burst mode */
59#define ACPI_EC_FLAG_SCI 0x20 /* EC-SCI occurred */
60
61/* EC commands */
62enum ec_command {
63 ACPI_EC_COMMAND_READ = 0x80,
64 ACPI_EC_COMMAND_WRITE = 0x81,
65 ACPI_EC_BURST_ENABLE = 0x82,
66 ACPI_EC_BURST_DISABLE = 0x83,
67 ACPI_EC_COMMAND_QUERY = 0x84,
68};
69
70#define ACPI_EC_DELAY 500 /* Wait 500ms max. during EC ops */
71#define ACPI_EC_UDELAY_GLK 1000 /* Wait 1ms max. to get global lock */
72#define ACPI_EC_MSI_UDELAY 550 /* Wait 550us for MSI EC */
73
74#define ACPI_EC_STORM_THRESHOLD 8 /* number of false interrupts
75 per one transaction */
76
77enum {
78 EC_FLAGS_QUERY_PENDING, /* Query is pending */
79 EC_FLAGS_GPE_STORM, /* GPE storm detected */
80 EC_FLAGS_HANDLERS_INSTALLED, /* Handlers for GPE and
81 * OpReg are installed */
82 EC_FLAGS_BLOCKED, /* Transactions are blocked */
83};
84
85/* ec.c is compiled in acpi namespace so this shows up as acpi.ec_delay param */
86static unsigned int ec_delay __read_mostly = ACPI_EC_DELAY;
87module_param(ec_delay, uint, 0644);
88MODULE_PARM_DESC(ec_delay, "Timeout(ms) waited until an EC command completes");
89
90/* If we find an EC via the ECDT, we need to keep a ptr to its context */
91/* External interfaces use first EC only, so remember */
92typedef int (*acpi_ec_query_func) (void *data);
93
94struct acpi_ec_query_handler {
95 struct list_head node;
96 acpi_ec_query_func func;
97 acpi_handle handle;
98 void *data;
99 u8 query_bit;
100};
101
102struct transaction {
103 const u8 *wdata;
104 u8 *rdata;
105 unsigned short irq_count;
106 u8 command;
107 u8 wi;
108 u8 ri;
109 u8 wlen;
110 u8 rlen;
111 bool done;
112};
113
114struct acpi_ec *boot_ec, *first_ec;
115EXPORT_SYMBOL(first_ec);
116
117static int EC_FLAGS_MSI; /* Out-of-spec MSI controller */
118static int EC_FLAGS_VALIDATE_ECDT; /* ASUStec ECDTs need to be validated */
119static int EC_FLAGS_SKIP_DSDT_SCAN; /* Not all BIOS survive early DSDT scan */
120
121/* --------------------------------------------------------------------------
122 Transaction Management
123 -------------------------------------------------------------------------- */
124
125static inline u8 acpi_ec_read_status(struct acpi_ec *ec)
126{
127 u8 x = inb(ec->command_addr);
128 pr_debug(PREFIX "---> status = 0x%2.2x\n", x);
129 return x;
130}
131
132static inline u8 acpi_ec_read_data(struct acpi_ec *ec)
133{
134 u8 x = inb(ec->data_addr);
135 pr_debug(PREFIX "---> data = 0x%2.2x\n", x);
136 return x;
137}
138
139static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command)
140{
141 pr_debug(PREFIX "<--- command = 0x%2.2x\n", command);
142 outb(command, ec->command_addr);
143}
144
145static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data)
146{
147 pr_debug(PREFIX "<--- data = 0x%2.2x\n", data);
148 outb(data, ec->data_addr);
149}
150
151static int ec_transaction_done(struct acpi_ec *ec)
152{
153 unsigned long flags;
154 int ret = 0;
155 spin_lock_irqsave(&ec->curr_lock, flags);
156 if (!ec->curr || ec->curr->done)
157 ret = 1;
158 spin_unlock_irqrestore(&ec->curr_lock, flags);
159 return ret;
160}
161
162static void start_transaction(struct acpi_ec *ec)
163{
164 ec->curr->irq_count = ec->curr->wi = ec->curr->ri = 0;
165 ec->curr->done = false;
166 acpi_ec_write_cmd(ec, ec->curr->command);
167}
168
169static void advance_transaction(struct acpi_ec *ec, u8 status)
170{
171 unsigned long flags;
172 spin_lock_irqsave(&ec->curr_lock, flags);
173 if (!ec->curr)
174 goto unlock;
175 if (ec->curr->wlen > ec->curr->wi) {
176 if ((status & ACPI_EC_FLAG_IBF) == 0)
177 acpi_ec_write_data(ec,
178 ec->curr->wdata[ec->curr->wi++]);
179 else
180 goto err;
181 } else if (ec->curr->rlen > ec->curr->ri) {
182 if ((status & ACPI_EC_FLAG_OBF) == 1) {
183 ec->curr->rdata[ec->curr->ri++] = acpi_ec_read_data(ec);
184 if (ec->curr->rlen == ec->curr->ri)
185 ec->curr->done = true;
186 } else
187 goto err;
188 } else if (ec->curr->wlen == ec->curr->wi &&
189 (status & ACPI_EC_FLAG_IBF) == 0)
190 ec->curr->done = true;
191 goto unlock;
192err:
193 /* false interrupt, state didn't change */
194 if (in_interrupt())
195 ++ec->curr->irq_count;
196unlock:
197 spin_unlock_irqrestore(&ec->curr_lock, flags);
198}
199
200static int acpi_ec_sync_query(struct acpi_ec *ec);
201
202static int ec_check_sci_sync(struct acpi_ec *ec, u8 state)
203{
204 if (state & ACPI_EC_FLAG_SCI) {
205 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags))
206 return acpi_ec_sync_query(ec);
207 }
208 return 0;
209}
210
211static int ec_poll(struct acpi_ec *ec)
212{
213 unsigned long flags;
214 int repeat = 2; /* number of command restarts */
215 while (repeat--) {
216 unsigned long delay = jiffies +
217 msecs_to_jiffies(ec_delay);
218 do {
219 /* don't sleep with disabled interrupts */
220 if (EC_FLAGS_MSI || irqs_disabled()) {
221 udelay(ACPI_EC_MSI_UDELAY);
222 if (ec_transaction_done(ec))
223 return 0;
224 } else {
225 if (wait_event_timeout(ec->wait,
226 ec_transaction_done(ec),
227 msecs_to_jiffies(1)))
228 return 0;
229 }
230 advance_transaction(ec, acpi_ec_read_status(ec));
231 } while (time_before(jiffies, delay));
232 if (acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF)
233 break;
234 pr_debug(PREFIX "controller reset, restart transaction\n");
235 spin_lock_irqsave(&ec->curr_lock, flags);
236 start_transaction(ec);
237 spin_unlock_irqrestore(&ec->curr_lock, flags);
238 }
239 return -ETIME;
240}
241
242static int acpi_ec_transaction_unlocked(struct acpi_ec *ec,
243 struct transaction *t)
244{
245 unsigned long tmp;
246 int ret = 0;
247 if (EC_FLAGS_MSI)
248 udelay(ACPI_EC_MSI_UDELAY);
249 /* start transaction */
250 spin_lock_irqsave(&ec->curr_lock, tmp);
251 /* following two actions should be kept atomic */
252 ec->curr = t;
253 start_transaction(ec);
254 if (ec->curr->command == ACPI_EC_COMMAND_QUERY)
255 clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
256 spin_unlock_irqrestore(&ec->curr_lock, tmp);
257 ret = ec_poll(ec);
258 spin_lock_irqsave(&ec->curr_lock, tmp);
259 ec->curr = NULL;
260 spin_unlock_irqrestore(&ec->curr_lock, tmp);
261 return ret;
262}
263
264static int ec_check_ibf0(struct acpi_ec *ec)
265{
266 u8 status = acpi_ec_read_status(ec);
267 return (status & ACPI_EC_FLAG_IBF) == 0;
268}
269
270static int ec_wait_ibf0(struct acpi_ec *ec)
271{
272 unsigned long delay = jiffies + msecs_to_jiffies(ec_delay);
273 /* interrupt wait manually if GPE mode is not active */
274 while (time_before(jiffies, delay))
275 if (wait_event_timeout(ec->wait, ec_check_ibf0(ec),
276 msecs_to_jiffies(1)))
277 return 0;
278 return -ETIME;
279}
280
281static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t)
282{
283 int status;
284 u32 glk;
285 if (!ec || (!t) || (t->wlen && !t->wdata) || (t->rlen && !t->rdata))
286 return -EINVAL;
287 if (t->rdata)
288 memset(t->rdata, 0, t->rlen);
289 mutex_lock(&ec->lock);
290 if (test_bit(EC_FLAGS_BLOCKED, &ec->flags)) {
291 status = -EINVAL;
292 goto unlock;
293 }
294 if (ec->global_lock) {
295 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
296 if (ACPI_FAILURE(status)) {
297 status = -ENODEV;
298 goto unlock;
299 }
300 }
301 if (ec_wait_ibf0(ec)) {
302 pr_err(PREFIX "input buffer is not empty, "
303 "aborting transaction\n");
304 status = -ETIME;
305 goto end;
306 }
307 pr_debug(PREFIX "transaction start\n");
308 /* disable GPE during transaction if storm is detected */
309 if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
310 /* It has to be disabled, so that it doesn't trigger. */
311 acpi_disable_gpe(NULL, ec->gpe);
312 }
313
314 status = acpi_ec_transaction_unlocked(ec, t);
315
316 /* check if we received SCI during transaction */
317 ec_check_sci_sync(ec, acpi_ec_read_status(ec));
318 if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
319 msleep(1);
320 /* It is safe to enable the GPE outside of the transaction. */
321 acpi_enable_gpe(NULL, ec->gpe);
322 } else if (t->irq_count > ACPI_EC_STORM_THRESHOLD) {
323 pr_info(PREFIX "GPE storm detected, "
324 "transactions will use polling mode\n");
325 set_bit(EC_FLAGS_GPE_STORM, &ec->flags);
326 }
327 pr_debug(PREFIX "transaction end\n");
328end:
329 if (ec->global_lock)
330 acpi_release_global_lock(glk);
331unlock:
332 mutex_unlock(&ec->lock);
333 return status;
334}
335
336static int acpi_ec_burst_enable(struct acpi_ec *ec)
337{
338 u8 d;
339 struct transaction t = {.command = ACPI_EC_BURST_ENABLE,
340 .wdata = NULL, .rdata = &d,
341 .wlen = 0, .rlen = 1};
342
343 return acpi_ec_transaction(ec, &t);
344}
345
346static int acpi_ec_burst_disable(struct acpi_ec *ec)
347{
348 struct transaction t = {.command = ACPI_EC_BURST_DISABLE,
349 .wdata = NULL, .rdata = NULL,
350 .wlen = 0, .rlen = 0};
351
352 return (acpi_ec_read_status(ec) & ACPI_EC_FLAG_BURST) ?
353 acpi_ec_transaction(ec, &t) : 0;
354}
355
356static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 * data)
357{
358 int result;
359 u8 d;
360 struct transaction t = {.command = ACPI_EC_COMMAND_READ,
361 .wdata = &address, .rdata = &d,
362 .wlen = 1, .rlen = 1};
363
364 result = acpi_ec_transaction(ec, &t);
365 *data = d;
366 return result;
367}
368
369static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
370{
371 u8 wdata[2] = { address, data };
372 struct transaction t = {.command = ACPI_EC_COMMAND_WRITE,
373 .wdata = wdata, .rdata = NULL,
374 .wlen = 2, .rlen = 0};
375
376 return acpi_ec_transaction(ec, &t);
377}
378
379/*
380 * Externally callable EC access functions. For now, assume 1 EC only
381 */
382int ec_burst_enable(void)
383{
384 if (!first_ec)
385 return -ENODEV;
386 return acpi_ec_burst_enable(first_ec);
387}
388
389EXPORT_SYMBOL(ec_burst_enable);
390
391int ec_burst_disable(void)
392{
393 if (!first_ec)
394 return -ENODEV;
395 return acpi_ec_burst_disable(first_ec);
396}
397
398EXPORT_SYMBOL(ec_burst_disable);
399
400int ec_read(u8 addr, u8 * val)
401{
402 int err;
403 u8 temp_data;
404
405 if (!first_ec)
406 return -ENODEV;
407
408 err = acpi_ec_read(first_ec, addr, &temp_data);
409
410 if (!err) {
411 *val = temp_data;
412 return 0;
413 } else
414 return err;
415}
416
417EXPORT_SYMBOL(ec_read);
418
419int ec_write(u8 addr, u8 val)
420{
421 int err;
422
423 if (!first_ec)
424 return -ENODEV;
425
426 err = acpi_ec_write(first_ec, addr, val);
427
428 return err;
429}
430
431EXPORT_SYMBOL(ec_write);
432
433int ec_transaction(u8 command,
434 const u8 * wdata, unsigned wdata_len,
435 u8 * rdata, unsigned rdata_len)
436{
437 struct transaction t = {.command = command,
438 .wdata = wdata, .rdata = rdata,
439 .wlen = wdata_len, .rlen = rdata_len};
440 if (!first_ec)
441 return -ENODEV;
442
443 return acpi_ec_transaction(first_ec, &t);
444}
445
446EXPORT_SYMBOL(ec_transaction);
447
448void acpi_ec_block_transactions(void)
449{
450 struct acpi_ec *ec = first_ec;
451
452 if (!ec)
453 return;
454
455 mutex_lock(&ec->lock);
456 /* Prevent transactions from being carried out */
457 set_bit(EC_FLAGS_BLOCKED, &ec->flags);
458 mutex_unlock(&ec->lock);
459}
460
461void acpi_ec_unblock_transactions(void)
462{
463 struct acpi_ec *ec = first_ec;
464
465 if (!ec)
466 return;
467
468 mutex_lock(&ec->lock);
469 /* Allow transactions to be carried out again */
470 clear_bit(EC_FLAGS_BLOCKED, &ec->flags);
471 mutex_unlock(&ec->lock);
472}
473
474void acpi_ec_unblock_transactions_early(void)
475{
476 /*
477 * Allow transactions to happen again (this function is called from
478 * atomic context during wakeup, so we don't need to acquire the mutex).
479 */
480 if (first_ec)
481 clear_bit(EC_FLAGS_BLOCKED, &first_ec->flags);
482}
483
484static int acpi_ec_query_unlocked(struct acpi_ec *ec, u8 * data)
485{
486 int result;
487 u8 d;
488 struct transaction t = {.command = ACPI_EC_COMMAND_QUERY,
489 .wdata = NULL, .rdata = &d,
490 .wlen = 0, .rlen = 1};
491 if (!ec || !data)
492 return -EINVAL;
493 /*
494 * Query the EC to find out which _Qxx method we need to evaluate.
495 * Note that successful completion of the query causes the ACPI_EC_SCI
496 * bit to be cleared (and thus clearing the interrupt source).
497 */
498 result = acpi_ec_transaction_unlocked(ec, &t);
499 if (result)
500 return result;
501 if (!d)
502 return -ENODATA;
503 *data = d;
504 return 0;
505}
506
507/* --------------------------------------------------------------------------
508 Event Management
509 -------------------------------------------------------------------------- */
510int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
511 acpi_handle handle, acpi_ec_query_func func,
512 void *data)
513{
514 struct acpi_ec_query_handler *handler =
515 kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL);
516 if (!handler)
517 return -ENOMEM;
518
519 handler->query_bit = query_bit;
520 handler->handle = handle;
521 handler->func = func;
522 handler->data = data;
523 mutex_lock(&ec->lock);
524 list_add(&handler->node, &ec->list);
525 mutex_unlock(&ec->lock);
526 return 0;
527}
528
529EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler);
530
531void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit)
532{
533 struct acpi_ec_query_handler *handler, *tmp;
534 mutex_lock(&ec->lock);
535 list_for_each_entry_safe(handler, tmp, &ec->list, node) {
536 if (query_bit == handler->query_bit) {
537 list_del(&handler->node);
538 kfree(handler);
539 }
540 }
541 mutex_unlock(&ec->lock);
542}
543
544EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler);
545
546static void acpi_ec_run(void *cxt)
547{
548 struct acpi_ec_query_handler *handler = cxt;
549 if (!handler)
550 return;
551 pr_debug(PREFIX "start query execution\n");
552 if (handler->func)
553 handler->func(handler->data);
554 else if (handler->handle)
555 acpi_evaluate_object(handler->handle, NULL, NULL, NULL);
556 pr_debug(PREFIX "stop query execution\n");
557 kfree(handler);
558}
559
560static int acpi_ec_sync_query(struct acpi_ec *ec)
561{
562 u8 value = 0;
563 int status;
564 struct acpi_ec_query_handler *handler, *copy;
565 if ((status = acpi_ec_query_unlocked(ec, &value)))
566 return status;
567 list_for_each_entry(handler, &ec->list, node) {
568 if (value == handler->query_bit) {
569 /* have custom handler for this bit */
570 copy = kmalloc(sizeof(*handler), GFP_KERNEL);
571 if (!copy)
572 return -ENOMEM;
573 memcpy(copy, handler, sizeof(*copy));
574 pr_debug(PREFIX "push query execution (0x%2x) on queue\n", value);
575 return acpi_os_execute((copy->func) ?
576 OSL_NOTIFY_HANDLER : OSL_GPE_HANDLER,
577 acpi_ec_run, copy);
578 }
579 }
580 return 0;
581}
582
583static void acpi_ec_gpe_query(void *ec_cxt)
584{
585 struct acpi_ec *ec = ec_cxt;
586 if (!ec)
587 return;
588 mutex_lock(&ec->lock);
589 acpi_ec_sync_query(ec);
590 mutex_unlock(&ec->lock);
591}
592
593static int ec_check_sci(struct acpi_ec *ec, u8 state)
594{
595 if (state & ACPI_EC_FLAG_SCI) {
596 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) {
597 pr_debug(PREFIX "push gpe query to the queue\n");
598 return acpi_os_execute(OSL_NOTIFY_HANDLER,
599 acpi_ec_gpe_query, ec);
600 }
601 }
602 return 0;
603}
604
605static u32 acpi_ec_gpe_handler(acpi_handle gpe_device,
606 u32 gpe_number, void *data)
607{
608 struct acpi_ec *ec = data;
609
610 pr_debug(PREFIX "~~~> interrupt\n");
611
612 advance_transaction(ec, acpi_ec_read_status(ec));
613 if (ec_transaction_done(ec) &&
614 (acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF) == 0) {
615 wake_up(&ec->wait);
616 ec_check_sci(ec, acpi_ec_read_status(ec));
617 }
618 return ACPI_INTERRUPT_HANDLED | ACPI_REENABLE_GPE;
619}
620
621/* --------------------------------------------------------------------------
622 Address Space Management
623 -------------------------------------------------------------------------- */
624
625static acpi_status
626acpi_ec_space_handler(u32 function, acpi_physical_address address,
627 u32 bits, u64 *value64,
628 void *handler_context, void *region_context)
629{
630 struct acpi_ec *ec = handler_context;
631 int result = 0, i, bytes = bits / 8;
632 u8 *value = (u8 *)value64;
633
634 if ((address > 0xFF) || !value || !handler_context)
635 return AE_BAD_PARAMETER;
636
637 if (function != ACPI_READ && function != ACPI_WRITE)
638 return AE_BAD_PARAMETER;
639
640 if (EC_FLAGS_MSI || bits > 8)
641 acpi_ec_burst_enable(ec);
642
643 for (i = 0; i < bytes; ++i, ++address, ++value)
644 result = (function == ACPI_READ) ?
645 acpi_ec_read(ec, address, value) :
646 acpi_ec_write(ec, address, *value);
647
648 if (EC_FLAGS_MSI || bits > 8)
649 acpi_ec_burst_disable(ec);
650
651 switch (result) {
652 case -EINVAL:
653 return AE_BAD_PARAMETER;
654 break;
655 case -ENODEV:
656 return AE_NOT_FOUND;
657 break;
658 case -ETIME:
659 return AE_TIME;
660 break;
661 default:
662 return AE_OK;
663 }
664}
665
666/* --------------------------------------------------------------------------
667 Driver Interface
668 -------------------------------------------------------------------------- */
669static acpi_status
670ec_parse_io_ports(struct acpi_resource *resource, void *context);
671
672static struct acpi_ec *make_acpi_ec(void)
673{
674 struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
675 if (!ec)
676 return NULL;
677 ec->flags = 1 << EC_FLAGS_QUERY_PENDING;
678 mutex_init(&ec->lock);
679 init_waitqueue_head(&ec->wait);
680 INIT_LIST_HEAD(&ec->list);
681 spin_lock_init(&ec->curr_lock);
682 return ec;
683}
684
685static acpi_status
686acpi_ec_register_query_methods(acpi_handle handle, u32 level,
687 void *context, void **return_value)
688{
689 char node_name[5];
690 struct acpi_buffer buffer = { sizeof(node_name), node_name };
691 struct acpi_ec *ec = context;
692 int value = 0;
693 acpi_status status;
694
695 status = acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
696
697 if (ACPI_SUCCESS(status) && sscanf(node_name, "_Q%x", &value) == 1) {
698 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL);
699 }
700 return AE_OK;
701}
702
703static acpi_status
704ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
705{
706 acpi_status status;
707 unsigned long long tmp = 0;
708
709 struct acpi_ec *ec = context;
710
711 /* clear addr values, ec_parse_io_ports depend on it */
712 ec->command_addr = ec->data_addr = 0;
713
714 status = acpi_walk_resources(handle, METHOD_NAME__CRS,
715 ec_parse_io_ports, ec);
716 if (ACPI_FAILURE(status))
717 return status;
718
719 /* Get GPE bit assignment (EC events). */
720 /* TODO: Add support for _GPE returning a package */
721 status = acpi_evaluate_integer(handle, "_GPE", NULL, &tmp);
722 if (ACPI_FAILURE(status))
723 return status;
724 ec->gpe = tmp;
725 /* Use the global lock for all EC transactions? */
726 tmp = 0;
727 acpi_evaluate_integer(handle, "_GLK", NULL, &tmp);
728 ec->global_lock = tmp;
729 ec->handle = handle;
730 return AE_CTRL_TERMINATE;
731}
732
733static int ec_install_handlers(struct acpi_ec *ec)
734{
735 acpi_status status;
736 if (test_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags))
737 return 0;
738 status = acpi_install_gpe_handler(NULL, ec->gpe,
739 ACPI_GPE_EDGE_TRIGGERED,
740 &acpi_ec_gpe_handler, ec);
741 if (ACPI_FAILURE(status))
742 return -ENODEV;
743
744 acpi_enable_gpe(NULL, ec->gpe);
745 status = acpi_install_address_space_handler(ec->handle,
746 ACPI_ADR_SPACE_EC,
747 &acpi_ec_space_handler,
748 NULL, ec);
749 if (ACPI_FAILURE(status)) {
750 if (status == AE_NOT_FOUND) {
751 /*
752 * Maybe OS fails in evaluating the _REG object.
753 * The AE_NOT_FOUND error will be ignored and OS
754 * continue to initialize EC.
755 */
756 printk(KERN_ERR "Fail in evaluating the _REG object"
757 " of EC device. Broken bios is suspected.\n");
758 } else {
759 acpi_remove_gpe_handler(NULL, ec->gpe,
760 &acpi_ec_gpe_handler);
761 acpi_disable_gpe(NULL, ec->gpe);
762 return -ENODEV;
763 }
764 }
765
766 set_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
767 return 0;
768}
769
770static void ec_remove_handlers(struct acpi_ec *ec)
771{
772 acpi_disable_gpe(NULL, ec->gpe);
773 if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle,
774 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler)))
775 pr_err(PREFIX "failed to remove space handler\n");
776 if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe,
777 &acpi_ec_gpe_handler)))
778 pr_err(PREFIX "failed to remove gpe handler\n");
779 clear_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
780}
781
782static int acpi_ec_add(struct acpi_device *device)
783{
784 struct acpi_ec *ec = NULL;
785 int ret;
786
787 strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
788 strcpy(acpi_device_class(device), ACPI_EC_CLASS);
789
790 /* Check for boot EC */
791 if (boot_ec &&
792 (boot_ec->handle == device->handle ||
793 boot_ec->handle == ACPI_ROOT_OBJECT)) {
794 ec = boot_ec;
795 boot_ec = NULL;
796 } else {
797 ec = make_acpi_ec();
798 if (!ec)
799 return -ENOMEM;
800 }
801 if (ec_parse_device(device->handle, 0, ec, NULL) !=
802 AE_CTRL_TERMINATE) {
803 kfree(ec);
804 return -EINVAL;
805 }
806
807 /* Find and register all query methods */
808 acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1,
809 acpi_ec_register_query_methods, NULL, ec, NULL);
810
811 if (!first_ec)
812 first_ec = ec;
813 device->driver_data = ec;
814
815 WARN(!request_region(ec->data_addr, 1, "EC data"),
816 "Could not request EC data io port 0x%lx", ec->data_addr);
817 WARN(!request_region(ec->command_addr, 1, "EC cmd"),
818 "Could not request EC cmd io port 0x%lx", ec->command_addr);
819
820 pr_info(PREFIX "GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n",
821 ec->gpe, ec->command_addr, ec->data_addr);
822
823 ret = ec_install_handlers(ec);
824
825 /* EC is fully operational, allow queries */
826 clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
827 return ret;
828}
829
830static int acpi_ec_remove(struct acpi_device *device, int type)
831{
832 struct acpi_ec *ec;
833 struct acpi_ec_query_handler *handler, *tmp;
834
835 if (!device)
836 return -EINVAL;
837
838 ec = acpi_driver_data(device);
839 ec_remove_handlers(ec);
840 mutex_lock(&ec->lock);
841 list_for_each_entry_safe(handler, tmp, &ec->list, node) {
842 list_del(&handler->node);
843 kfree(handler);
844 }
845 mutex_unlock(&ec->lock);
846 release_region(ec->data_addr, 1);
847 release_region(ec->command_addr, 1);
848 device->driver_data = NULL;
849 if (ec == first_ec)
850 first_ec = NULL;
851 kfree(ec);
852 return 0;
853}
854
855static acpi_status
856ec_parse_io_ports(struct acpi_resource *resource, void *context)
857{
858 struct acpi_ec *ec = context;
859
860 if (resource->type != ACPI_RESOURCE_TYPE_IO)
861 return AE_OK;
862
863 /*
864 * The first address region returned is the data port, and
865 * the second address region returned is the status/command
866 * port.
867 */
868 if (ec->data_addr == 0)
869 ec->data_addr = resource->data.io.minimum;
870 else if (ec->command_addr == 0)
871 ec->command_addr = resource->data.io.minimum;
872 else
873 return AE_CTRL_TERMINATE;
874
875 return AE_OK;
876}
877
878int __init acpi_boot_ec_enable(void)
879{
880 if (!boot_ec || test_bit(EC_FLAGS_HANDLERS_INSTALLED, &boot_ec->flags))
881 return 0;
882 if (!ec_install_handlers(boot_ec)) {
883 first_ec = boot_ec;
884 return 0;
885 }
886 return -EFAULT;
887}
888
889static const struct acpi_device_id ec_device_ids[] = {
890 {"PNP0C09", 0},
891 {"", 0},
892};
893
894/* Some BIOS do not survive early DSDT scan, skip it */
895static int ec_skip_dsdt_scan(const struct dmi_system_id *id)
896{
897 EC_FLAGS_SKIP_DSDT_SCAN = 1;
898 return 0;
899}
900
901/* ASUStek often supplies us with broken ECDT, validate it */
902static int ec_validate_ecdt(const struct dmi_system_id *id)
903{
904 EC_FLAGS_VALIDATE_ECDT = 1;
905 return 0;
906}
907
908/* MSI EC needs special treatment, enable it */
909static int ec_flag_msi(const struct dmi_system_id *id)
910{
911 printk(KERN_DEBUG PREFIX "Detected MSI hardware, enabling workarounds.\n");
912 EC_FLAGS_MSI = 1;
913 EC_FLAGS_VALIDATE_ECDT = 1;
914 return 0;
915}
916
917static struct dmi_system_id __initdata ec_dmi_table[] = {
918 {
919 ec_skip_dsdt_scan, "Compal JFL92", {
920 DMI_MATCH(DMI_BIOS_VENDOR, "COMPAL"),
921 DMI_MATCH(DMI_BOARD_NAME, "JFL92") }, NULL},
922 {
923 ec_flag_msi, "MSI hardware", {
924 DMI_MATCH(DMI_BIOS_VENDOR, "Micro-Star")}, NULL},
925 {
926 ec_flag_msi, "MSI hardware", {
927 DMI_MATCH(DMI_SYS_VENDOR, "Micro-Star")}, NULL},
928 {
929 ec_flag_msi, "MSI hardware", {
930 DMI_MATCH(DMI_CHASSIS_VENDOR, "MICRO-Star")}, NULL},
931 {
932 ec_flag_msi, "MSI hardware", {
933 DMI_MATCH(DMI_CHASSIS_VENDOR, "MICRO-STAR")}, NULL},
934 {
935 ec_flag_msi, "Quanta hardware", {
936 DMI_MATCH(DMI_SYS_VENDOR, "Quanta"),
937 DMI_MATCH(DMI_PRODUCT_NAME, "TW8/SW8/DW8"),}, NULL},
938 {
939 ec_flag_msi, "Quanta hardware", {
940 DMI_MATCH(DMI_SYS_VENDOR, "Quanta"),
941 DMI_MATCH(DMI_PRODUCT_NAME, "TW9/SW9"),}, NULL},
942 {
943 ec_validate_ecdt, "ASUS hardware", {
944 DMI_MATCH(DMI_BIOS_VENDOR, "ASUS") }, NULL},
945 {
946 ec_validate_ecdt, "ASUS hardware", {
947 DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer Inc.") }, NULL},
948 {},
949};
950
951
952int __init acpi_ec_ecdt_probe(void)
953{
954 acpi_status status;
955 struct acpi_ec *saved_ec = NULL;
956 struct acpi_table_ecdt *ecdt_ptr;
957
958 boot_ec = make_acpi_ec();
959 if (!boot_ec)
960 return -ENOMEM;
961 /*
962 * Generate a boot ec context
963 */
964 dmi_check_system(ec_dmi_table);
965 status = acpi_get_table(ACPI_SIG_ECDT, 1,
966 (struct acpi_table_header **)&ecdt_ptr);
967 if (ACPI_SUCCESS(status)) {
968 pr_info(PREFIX "EC description table is found, configuring boot EC\n");
969 boot_ec->command_addr = ecdt_ptr->control.address;
970 boot_ec->data_addr = ecdt_ptr->data.address;
971 boot_ec->gpe = ecdt_ptr->gpe;
972 boot_ec->handle = ACPI_ROOT_OBJECT;
973 acpi_get_handle(ACPI_ROOT_OBJECT, ecdt_ptr->id, &boot_ec->handle);
974 /* Don't trust ECDT, which comes from ASUSTek */
975 if (!EC_FLAGS_VALIDATE_ECDT)
976 goto install;
977 saved_ec = kmemdup(boot_ec, sizeof(struct acpi_ec), GFP_KERNEL);
978 if (!saved_ec)
979 return -ENOMEM;
980 /* fall through */
981 }
982
983 if (EC_FLAGS_SKIP_DSDT_SCAN)
984 return -ENODEV;
985
986 /* This workaround is needed only on some broken machines,
987 * which require early EC, but fail to provide ECDT */
988 printk(KERN_DEBUG PREFIX "Look up EC in DSDT\n");
989 status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device,
990 boot_ec, NULL);
991 /* Check that acpi_get_devices actually find something */
992 if (ACPI_FAILURE(status) || !boot_ec->handle)
993 goto error;
994 if (saved_ec) {
995 /* try to find good ECDT from ASUSTek */
996 if (saved_ec->command_addr != boot_ec->command_addr ||
997 saved_ec->data_addr != boot_ec->data_addr ||
998 saved_ec->gpe != boot_ec->gpe ||
999 saved_ec->handle != boot_ec->handle)
1000 pr_info(PREFIX "ASUSTek keeps feeding us with broken "
1001 "ECDT tables, which are very hard to workaround. "
1002 "Trying to use DSDT EC info instead. Please send "
1003 "output of acpidump to linux-acpi@vger.kernel.org\n");
1004 kfree(saved_ec);
1005 saved_ec = NULL;
1006 } else {
1007 /* We really need to limit this workaround, the only ASUS,
1008 * which needs it, has fake EC._INI method, so use it as flag.
1009 * Keep boot_ec struct as it will be needed soon.
1010 */
1011 acpi_handle dummy;
1012 if (!dmi_name_in_vendors("ASUS") ||
1013 ACPI_FAILURE(acpi_get_handle(boot_ec->handle, "_INI",
1014 &dummy)))
1015 return -ENODEV;
1016 }
1017install:
1018 if (!ec_install_handlers(boot_ec)) {
1019 first_ec = boot_ec;
1020 return 0;
1021 }
1022error:
1023 kfree(boot_ec);
1024 boot_ec = NULL;
1025 return -ENODEV;
1026}
1027
1028static struct acpi_driver acpi_ec_driver = {
1029 .name = "ec",
1030 .class = ACPI_EC_CLASS,
1031 .ids = ec_device_ids,
1032 .ops = {
1033 .add = acpi_ec_add,
1034 .remove = acpi_ec_remove,
1035 },
1036};
1037
1038int __init acpi_ec_init(void)
1039{
1040 int result = 0;
1041
1042 /* Now register the driver for the EC */
1043 result = acpi_bus_register_driver(&acpi_ec_driver);
1044 if (result < 0)
1045 return -ENODEV;
1046
1047 return result;
1048}
1049
1050/* EC driver currently not unloadable */
1051#if 0
1052static void __exit acpi_ec_exit(void)
1053{
1054
1055 acpi_bus_unregister_driver(&acpi_ec_driver);
1056 return;
1057}
1058#endif /* 0 */
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#define ACPI_EC_FILE_INFO "info"
38
39/* EC status register */
40#define ACPI_EC_FLAG_OBF 0x01 /* Output buffer full */
41#define ACPI_EC_FLAG_IBF 0x02 /* Input buffer full */
42#define ACPI_EC_FLAG_CMD 0x08 /* Input buffer contains a command */
43#define ACPI_EC_FLAG_BURST 0x10 /* burst mode */
44#define ACPI_EC_FLAG_SCI 0x20 /* EC-SCI occurred */
45
46/*
47 * The SCI_EVT clearing timing is not defined by the ACPI specification.
48 * This leads to lots of practical timing issues for the host EC driver.
49 * The following variations are defined (from the target EC firmware's
50 * perspective):
51 * STATUS: After indicating SCI_EVT edge triggered IRQ to the host, the
52 * target can clear SCI_EVT at any time so long as the host can see
53 * the indication by reading the status register (EC_SC). So the
54 * host should re-check SCI_EVT after the first time the SCI_EVT
55 * indication is seen, which is the same time the query request
56 * (QR_EC) is written to the command register (EC_CMD). SCI_EVT set
57 * at any later time could indicate another event. Normally such
58 * kind of EC firmware has implemented an event queue and will
59 * return 0x00 to indicate "no outstanding event".
60 * QUERY: After seeing the query request (QR_EC) written to the command
61 * register (EC_CMD) by the host and having prepared the responding
62 * event value in the data register (EC_DATA), the target can safely
63 * clear SCI_EVT because the target can confirm that the current
64 * event is being handled by the host. The host then should check
65 * SCI_EVT right after reading the event response from the data
66 * register (EC_DATA).
67 * EVENT: After seeing the event response read from the data register
68 * (EC_DATA) by the host, the target can clear SCI_EVT. As the
69 * target requires time to notice the change in the data register
70 * (EC_DATA), the host may be required to wait additional guarding
71 * time before checking the SCI_EVT again. Such guarding may not be
72 * necessary if the host is notified via another IRQ.
73 */
74#define ACPI_EC_EVT_TIMING_STATUS 0x00
75#define ACPI_EC_EVT_TIMING_QUERY 0x01
76#define ACPI_EC_EVT_TIMING_EVENT 0x02
77
78/* EC commands */
79enum ec_command {
80 ACPI_EC_COMMAND_READ = 0x80,
81 ACPI_EC_COMMAND_WRITE = 0x81,
82 ACPI_EC_BURST_ENABLE = 0x82,
83 ACPI_EC_BURST_DISABLE = 0x83,
84 ACPI_EC_COMMAND_QUERY = 0x84,
85};
86
87#define ACPI_EC_DELAY 500 /* Wait 500ms max. during EC ops */
88#define ACPI_EC_UDELAY_GLK 1000 /* Wait 1ms max. to get global lock */
89#define ACPI_EC_UDELAY_POLL 550 /* Wait 1ms for EC transaction polling */
90#define ACPI_EC_CLEAR_MAX 100 /* Maximum number of events to query
91 * when trying to clear the EC */
92#define ACPI_EC_MAX_QUERIES 16 /* Maximum number of parallel queries */
93
94enum {
95 EC_FLAGS_QUERY_ENABLED, /* Query is enabled */
96 EC_FLAGS_QUERY_PENDING, /* Query is pending */
97 EC_FLAGS_QUERY_GUARDING, /* Guard for SCI_EVT check */
98 EC_FLAGS_GPE_HANDLER_INSTALLED, /* GPE handler installed */
99 EC_FLAGS_EC_HANDLER_INSTALLED, /* OpReg handler installed */
100 EC_FLAGS_EVT_HANDLER_INSTALLED, /* _Qxx handlers installed */
101 EC_FLAGS_STARTED, /* Driver is started */
102 EC_FLAGS_STOPPED, /* Driver is stopped */
103 EC_FLAGS_GPE_MASKED, /* GPE masked */
104};
105
106#define ACPI_EC_COMMAND_POLL 0x01 /* Available for command byte */
107#define ACPI_EC_COMMAND_COMPLETE 0x02 /* Completed last byte */
108
109/* ec.c is compiled in acpi namespace so this shows up as acpi.ec_delay param */
110static unsigned int ec_delay __read_mostly = ACPI_EC_DELAY;
111module_param(ec_delay, uint, 0644);
112MODULE_PARM_DESC(ec_delay, "Timeout(ms) waited until an EC command completes");
113
114static unsigned int ec_max_queries __read_mostly = ACPI_EC_MAX_QUERIES;
115module_param(ec_max_queries, uint, 0644);
116MODULE_PARM_DESC(ec_max_queries, "Maximum parallel _Qxx evaluations");
117
118static bool ec_busy_polling __read_mostly;
119module_param(ec_busy_polling, bool, 0644);
120MODULE_PARM_DESC(ec_busy_polling, "Use busy polling to advance EC transaction");
121
122static unsigned int ec_polling_guard __read_mostly = ACPI_EC_UDELAY_POLL;
123module_param(ec_polling_guard, uint, 0644);
124MODULE_PARM_DESC(ec_polling_guard, "Guard time(us) between EC accesses in polling modes");
125
126static unsigned int ec_event_clearing __read_mostly = ACPI_EC_EVT_TIMING_QUERY;
127
128/*
129 * If the number of false interrupts per one transaction exceeds
130 * this threshold, will think there is a GPE storm happened and
131 * will disable the GPE for normal transaction.
132 */
133static unsigned int ec_storm_threshold __read_mostly = 8;
134module_param(ec_storm_threshold, uint, 0644);
135MODULE_PARM_DESC(ec_storm_threshold, "Maxim false GPE numbers not considered as GPE storm");
136
137static bool ec_freeze_events __read_mostly = false;
138module_param(ec_freeze_events, bool, 0644);
139MODULE_PARM_DESC(ec_freeze_events, "Disabling event handling during suspend/resume");
140
141static bool ec_no_wakeup __read_mostly;
142module_param(ec_no_wakeup, bool, 0644);
143MODULE_PARM_DESC(ec_no_wakeup, "Do not wake up from suspend-to-idle");
144
145struct acpi_ec_query_handler {
146 struct list_head node;
147 acpi_ec_query_func func;
148 acpi_handle handle;
149 void *data;
150 u8 query_bit;
151 struct kref kref;
152};
153
154struct transaction {
155 const u8 *wdata;
156 u8 *rdata;
157 unsigned short irq_count;
158 u8 command;
159 u8 wi;
160 u8 ri;
161 u8 wlen;
162 u8 rlen;
163 u8 flags;
164};
165
166struct acpi_ec_query {
167 struct transaction transaction;
168 struct work_struct work;
169 struct acpi_ec_query_handler *handler;
170};
171
172static int acpi_ec_query(struct acpi_ec *ec, u8 *data);
173static void advance_transaction(struct acpi_ec *ec);
174static void acpi_ec_event_handler(struct work_struct *work);
175static void acpi_ec_event_processor(struct work_struct *work);
176
177struct acpi_ec *first_ec;
178EXPORT_SYMBOL(first_ec);
179
180static struct acpi_ec *boot_ec;
181static bool boot_ec_is_ecdt = false;
182static struct workqueue_struct *ec_query_wq;
183
184static int EC_FLAGS_QUERY_HANDSHAKE; /* Needs QR_EC issued when SCI_EVT set */
185static int EC_FLAGS_CORRECT_ECDT; /* Needs ECDT port address correction */
186static int EC_FLAGS_IGNORE_DSDT_GPE; /* Needs ECDT GPE as correction setting */
187static int EC_FLAGS_CLEAR_ON_RESUME; /* Needs acpi_ec_clear() on boot/resume */
188
189/* --------------------------------------------------------------------------
190 * Logging/Debugging
191 * -------------------------------------------------------------------------- */
192
193/*
194 * Splitters used by the developers to track the boundary of the EC
195 * handling processes.
196 */
197#ifdef DEBUG
198#define EC_DBG_SEP " "
199#define EC_DBG_DRV "+++++"
200#define EC_DBG_STM "====="
201#define EC_DBG_REQ "*****"
202#define EC_DBG_EVT "#####"
203#else
204#define EC_DBG_SEP ""
205#define EC_DBG_DRV
206#define EC_DBG_STM
207#define EC_DBG_REQ
208#define EC_DBG_EVT
209#endif
210
211#define ec_log_raw(fmt, ...) \
212 pr_info(fmt "\n", ##__VA_ARGS__)
213#define ec_dbg_raw(fmt, ...) \
214 pr_debug(fmt "\n", ##__VA_ARGS__)
215#define ec_log(filter, fmt, ...) \
216 ec_log_raw(filter EC_DBG_SEP fmt EC_DBG_SEP filter, ##__VA_ARGS__)
217#define ec_dbg(filter, fmt, ...) \
218 ec_dbg_raw(filter EC_DBG_SEP fmt EC_DBG_SEP filter, ##__VA_ARGS__)
219
220#define ec_log_drv(fmt, ...) \
221 ec_log(EC_DBG_DRV, fmt, ##__VA_ARGS__)
222#define ec_dbg_drv(fmt, ...) \
223 ec_dbg(EC_DBG_DRV, fmt, ##__VA_ARGS__)
224#define ec_dbg_stm(fmt, ...) \
225 ec_dbg(EC_DBG_STM, fmt, ##__VA_ARGS__)
226#define ec_dbg_req(fmt, ...) \
227 ec_dbg(EC_DBG_REQ, fmt, ##__VA_ARGS__)
228#define ec_dbg_evt(fmt, ...) \
229 ec_dbg(EC_DBG_EVT, fmt, ##__VA_ARGS__)
230#define ec_dbg_ref(ec, fmt, ...) \
231 ec_dbg_raw("%lu: " fmt, ec->reference_count, ## __VA_ARGS__)
232
233/* --------------------------------------------------------------------------
234 * Device Flags
235 * -------------------------------------------------------------------------- */
236
237static bool acpi_ec_started(struct acpi_ec *ec)
238{
239 return test_bit(EC_FLAGS_STARTED, &ec->flags) &&
240 !test_bit(EC_FLAGS_STOPPED, &ec->flags);
241}
242
243static bool acpi_ec_event_enabled(struct acpi_ec *ec)
244{
245 /*
246 * There is an OSPM early stage logic. During the early stages
247 * (boot/resume), OSPMs shouldn't enable the event handling, only
248 * the EC transactions are allowed to be performed.
249 */
250 if (!test_bit(EC_FLAGS_QUERY_ENABLED, &ec->flags))
251 return false;
252 /*
253 * However, disabling the event handling is experimental for late
254 * stage (suspend), and is controlled by the boot parameter of
255 * "ec_freeze_events":
256 * 1. true: The EC event handling is disabled before entering
257 * the noirq stage.
258 * 2. false: The EC event handling is automatically disabled as
259 * soon as the EC driver is stopped.
260 */
261 if (ec_freeze_events)
262 return acpi_ec_started(ec);
263 else
264 return test_bit(EC_FLAGS_STARTED, &ec->flags);
265}
266
267static bool acpi_ec_flushed(struct acpi_ec *ec)
268{
269 return ec->reference_count == 1;
270}
271
272/* --------------------------------------------------------------------------
273 * EC Registers
274 * -------------------------------------------------------------------------- */
275
276static inline u8 acpi_ec_read_status(struct acpi_ec *ec)
277{
278 u8 x = inb(ec->command_addr);
279
280 ec_dbg_raw("EC_SC(R) = 0x%2.2x "
281 "SCI_EVT=%d BURST=%d CMD=%d IBF=%d OBF=%d",
282 x,
283 !!(x & ACPI_EC_FLAG_SCI),
284 !!(x & ACPI_EC_FLAG_BURST),
285 !!(x & ACPI_EC_FLAG_CMD),
286 !!(x & ACPI_EC_FLAG_IBF),
287 !!(x & ACPI_EC_FLAG_OBF));
288 return x;
289}
290
291static inline u8 acpi_ec_read_data(struct acpi_ec *ec)
292{
293 u8 x = inb(ec->data_addr);
294
295 ec->timestamp = jiffies;
296 ec_dbg_raw("EC_DATA(R) = 0x%2.2x", x);
297 return x;
298}
299
300static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command)
301{
302 ec_dbg_raw("EC_SC(W) = 0x%2.2x", command);
303 outb(command, ec->command_addr);
304 ec->timestamp = jiffies;
305}
306
307static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data)
308{
309 ec_dbg_raw("EC_DATA(W) = 0x%2.2x", data);
310 outb(data, ec->data_addr);
311 ec->timestamp = jiffies;
312}
313
314#if defined(DEBUG) || defined(CONFIG_DYNAMIC_DEBUG)
315static const char *acpi_ec_cmd_string(u8 cmd)
316{
317 switch (cmd) {
318 case 0x80:
319 return "RD_EC";
320 case 0x81:
321 return "WR_EC";
322 case 0x82:
323 return "BE_EC";
324 case 0x83:
325 return "BD_EC";
326 case 0x84:
327 return "QR_EC";
328 }
329 return "UNKNOWN";
330}
331#else
332#define acpi_ec_cmd_string(cmd) "UNDEF"
333#endif
334
335/* --------------------------------------------------------------------------
336 * GPE Registers
337 * -------------------------------------------------------------------------- */
338
339static inline bool acpi_ec_is_gpe_raised(struct acpi_ec *ec)
340{
341 acpi_event_status gpe_status = 0;
342
343 (void)acpi_get_gpe_status(NULL, ec->gpe, &gpe_status);
344 return (gpe_status & ACPI_EVENT_FLAG_STATUS_SET) ? true : false;
345}
346
347static inline void acpi_ec_enable_gpe(struct acpi_ec *ec, bool open)
348{
349 if (open)
350 acpi_enable_gpe(NULL, ec->gpe);
351 else {
352 BUG_ON(ec->reference_count < 1);
353 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_ENABLE);
354 }
355 if (acpi_ec_is_gpe_raised(ec)) {
356 /*
357 * On some platforms, EN=1 writes cannot trigger GPE. So
358 * software need to manually trigger a pseudo GPE event on
359 * EN=1 writes.
360 */
361 ec_dbg_raw("Polling quirk");
362 advance_transaction(ec);
363 }
364}
365
366static inline void acpi_ec_disable_gpe(struct acpi_ec *ec, bool close)
367{
368 if (close)
369 acpi_disable_gpe(NULL, ec->gpe);
370 else {
371 BUG_ON(ec->reference_count < 1);
372 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_DISABLE);
373 }
374}
375
376static inline void acpi_ec_clear_gpe(struct acpi_ec *ec)
377{
378 /*
379 * GPE STS is a W1C register, which means:
380 * 1. Software can clear it without worrying about clearing other
381 * GPEs' STS bits when the hardware sets them in parallel.
382 * 2. As long as software can ensure only clearing it when it is
383 * set, hardware won't set it in parallel.
384 * So software can clear GPE in any contexts.
385 * Warning: do not move the check into advance_transaction() as the
386 * EC commands will be sent without GPE raised.
387 */
388 if (!acpi_ec_is_gpe_raised(ec))
389 return;
390 acpi_clear_gpe(NULL, ec->gpe);
391}
392
393/* --------------------------------------------------------------------------
394 * Transaction Management
395 * -------------------------------------------------------------------------- */
396
397static void acpi_ec_submit_request(struct acpi_ec *ec)
398{
399 ec->reference_count++;
400 if (test_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags) &&
401 ec->reference_count == 1)
402 acpi_ec_enable_gpe(ec, true);
403}
404
405static void acpi_ec_complete_request(struct acpi_ec *ec)
406{
407 bool flushed = false;
408
409 ec->reference_count--;
410 if (test_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags) &&
411 ec->reference_count == 0)
412 acpi_ec_disable_gpe(ec, true);
413 flushed = acpi_ec_flushed(ec);
414 if (flushed)
415 wake_up(&ec->wait);
416}
417
418static void acpi_ec_mask_gpe(struct acpi_ec *ec)
419{
420 if (!test_bit(EC_FLAGS_GPE_MASKED, &ec->flags)) {
421 acpi_ec_disable_gpe(ec, false);
422 ec_dbg_drv("Polling enabled");
423 set_bit(EC_FLAGS_GPE_MASKED, &ec->flags);
424 }
425}
426
427static void acpi_ec_unmask_gpe(struct acpi_ec *ec)
428{
429 if (test_bit(EC_FLAGS_GPE_MASKED, &ec->flags)) {
430 clear_bit(EC_FLAGS_GPE_MASKED, &ec->flags);
431 acpi_ec_enable_gpe(ec, false);
432 ec_dbg_drv("Polling disabled");
433 }
434}
435
436/*
437 * acpi_ec_submit_flushable_request() - Increase the reference count unless
438 * the flush operation is not in
439 * progress
440 * @ec: the EC device
441 *
442 * This function must be used before taking a new action that should hold
443 * the reference count. If this function returns false, then the action
444 * must be discarded or it will prevent the flush operation from being
445 * completed.
446 */
447static bool acpi_ec_submit_flushable_request(struct acpi_ec *ec)
448{
449 if (!acpi_ec_started(ec))
450 return false;
451 acpi_ec_submit_request(ec);
452 return true;
453}
454
455static void acpi_ec_submit_query(struct acpi_ec *ec)
456{
457 acpi_ec_mask_gpe(ec);
458 if (!acpi_ec_event_enabled(ec))
459 return;
460 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) {
461 ec_dbg_evt("Command(%s) submitted/blocked",
462 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY));
463 ec->nr_pending_queries++;
464 schedule_work(&ec->work);
465 }
466}
467
468static void acpi_ec_complete_query(struct acpi_ec *ec)
469{
470 if (test_and_clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags))
471 ec_dbg_evt("Command(%s) unblocked",
472 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY));
473 acpi_ec_unmask_gpe(ec);
474}
475
476static inline void __acpi_ec_enable_event(struct acpi_ec *ec)
477{
478 if (!test_and_set_bit(EC_FLAGS_QUERY_ENABLED, &ec->flags))
479 ec_log_drv("event unblocked");
480 /*
481 * Unconditionally invoke this once after enabling the event
482 * handling mechanism to detect the pending events.
483 */
484 advance_transaction(ec);
485}
486
487static inline void __acpi_ec_disable_event(struct acpi_ec *ec)
488{
489 if (test_and_clear_bit(EC_FLAGS_QUERY_ENABLED, &ec->flags))
490 ec_log_drv("event blocked");
491}
492
493/*
494 * Process _Q events that might have accumulated in the EC.
495 * Run with locked ec mutex.
496 */
497static void acpi_ec_clear(struct acpi_ec *ec)
498{
499 int i, status;
500 u8 value = 0;
501
502 for (i = 0; i < ACPI_EC_CLEAR_MAX; i++) {
503 status = acpi_ec_query(ec, &value);
504 if (status || !value)
505 break;
506 }
507 if (unlikely(i == ACPI_EC_CLEAR_MAX))
508 pr_warn("Warning: Maximum of %d stale EC events cleared\n", i);
509 else
510 pr_info("%d stale EC events cleared\n", i);
511}
512
513static void acpi_ec_enable_event(struct acpi_ec *ec)
514{
515 unsigned long flags;
516
517 spin_lock_irqsave(&ec->lock, flags);
518 if (acpi_ec_started(ec))
519 __acpi_ec_enable_event(ec);
520 spin_unlock_irqrestore(&ec->lock, flags);
521
522 /* Drain additional events if hardware requires that */
523 if (EC_FLAGS_CLEAR_ON_RESUME)
524 acpi_ec_clear(ec);
525}
526
527#ifdef CONFIG_PM_SLEEP
528static bool acpi_ec_query_flushed(struct acpi_ec *ec)
529{
530 bool flushed;
531 unsigned long flags;
532
533 spin_lock_irqsave(&ec->lock, flags);
534 flushed = !ec->nr_pending_queries;
535 spin_unlock_irqrestore(&ec->lock, flags);
536 return flushed;
537}
538
539static void __acpi_ec_flush_event(struct acpi_ec *ec)
540{
541 /*
542 * When ec_freeze_events is true, we need to flush events in
543 * the proper position before entering the noirq stage.
544 */
545 wait_event(ec->wait, acpi_ec_query_flushed(ec));
546 if (ec_query_wq)
547 flush_workqueue(ec_query_wq);
548}
549
550static void acpi_ec_disable_event(struct acpi_ec *ec)
551{
552 unsigned long flags;
553
554 spin_lock_irqsave(&ec->lock, flags);
555 __acpi_ec_disable_event(ec);
556 spin_unlock_irqrestore(&ec->lock, flags);
557 __acpi_ec_flush_event(ec);
558}
559
560void acpi_ec_flush_work(void)
561{
562 if (first_ec)
563 __acpi_ec_flush_event(first_ec);
564
565 flush_scheduled_work();
566}
567#endif /* CONFIG_PM_SLEEP */
568
569static bool acpi_ec_guard_event(struct acpi_ec *ec)
570{
571 bool guarded = true;
572 unsigned long flags;
573
574 spin_lock_irqsave(&ec->lock, flags);
575 /*
576 * If firmware SCI_EVT clearing timing is "event", we actually
577 * don't know when the SCI_EVT will be cleared by firmware after
578 * evaluating _Qxx, so we need to re-check SCI_EVT after waiting an
579 * acceptable period.
580 *
581 * The guarding period begins when EC_FLAGS_QUERY_PENDING is
582 * flagged, which means SCI_EVT check has just been performed.
583 * But if the current transaction is ACPI_EC_COMMAND_QUERY, the
584 * guarding should have already been performed (via
585 * EC_FLAGS_QUERY_GUARDING) and should not be applied so that the
586 * ACPI_EC_COMMAND_QUERY transaction can be transitioned into
587 * ACPI_EC_COMMAND_POLL state immediately.
588 */
589 if (ec_event_clearing == ACPI_EC_EVT_TIMING_STATUS ||
590 ec_event_clearing == ACPI_EC_EVT_TIMING_QUERY ||
591 !test_bit(EC_FLAGS_QUERY_PENDING, &ec->flags) ||
592 (ec->curr && ec->curr->command == ACPI_EC_COMMAND_QUERY))
593 guarded = false;
594 spin_unlock_irqrestore(&ec->lock, flags);
595 return guarded;
596}
597
598static int ec_transaction_polled(struct acpi_ec *ec)
599{
600 unsigned long flags;
601 int ret = 0;
602
603 spin_lock_irqsave(&ec->lock, flags);
604 if (ec->curr && (ec->curr->flags & ACPI_EC_COMMAND_POLL))
605 ret = 1;
606 spin_unlock_irqrestore(&ec->lock, flags);
607 return ret;
608}
609
610static int ec_transaction_completed(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_COMPLETE))
617 ret = 1;
618 spin_unlock_irqrestore(&ec->lock, flags);
619 return ret;
620}
621
622static inline void ec_transaction_transition(struct acpi_ec *ec, unsigned long flag)
623{
624 ec->curr->flags |= flag;
625 if (ec->curr->command == ACPI_EC_COMMAND_QUERY) {
626 if (ec_event_clearing == ACPI_EC_EVT_TIMING_STATUS &&
627 flag == ACPI_EC_COMMAND_POLL)
628 acpi_ec_complete_query(ec);
629 if (ec_event_clearing == ACPI_EC_EVT_TIMING_QUERY &&
630 flag == ACPI_EC_COMMAND_COMPLETE)
631 acpi_ec_complete_query(ec);
632 if (ec_event_clearing == ACPI_EC_EVT_TIMING_EVENT &&
633 flag == ACPI_EC_COMMAND_COMPLETE)
634 set_bit(EC_FLAGS_QUERY_GUARDING, &ec->flags);
635 }
636}
637
638static void advance_transaction(struct acpi_ec *ec)
639{
640 struct transaction *t;
641 u8 status;
642 bool wakeup = false;
643
644 ec_dbg_stm("%s (%d)", in_interrupt() ? "IRQ" : "TASK",
645 smp_processor_id());
646 /*
647 * By always clearing STS before handling all indications, we can
648 * ensure a hardware STS 0->1 change after this clearing can always
649 * trigger a GPE interrupt.
650 */
651 acpi_ec_clear_gpe(ec);
652 status = acpi_ec_read_status(ec);
653 t = ec->curr;
654 /*
655 * Another IRQ or a guarded polling mode advancement is detected,
656 * the next QR_EC submission is then allowed.
657 */
658 if (!t || !(t->flags & ACPI_EC_COMMAND_POLL)) {
659 if (ec_event_clearing == ACPI_EC_EVT_TIMING_EVENT &&
660 (!ec->nr_pending_queries ||
661 test_bit(EC_FLAGS_QUERY_GUARDING, &ec->flags))) {
662 clear_bit(EC_FLAGS_QUERY_GUARDING, &ec->flags);
663 acpi_ec_complete_query(ec);
664 }
665 }
666 if (!t)
667 goto err;
668 if (t->flags & ACPI_EC_COMMAND_POLL) {
669 if (t->wlen > t->wi) {
670 if ((status & ACPI_EC_FLAG_IBF) == 0)
671 acpi_ec_write_data(ec, t->wdata[t->wi++]);
672 else
673 goto err;
674 } else if (t->rlen > t->ri) {
675 if ((status & ACPI_EC_FLAG_OBF) == 1) {
676 t->rdata[t->ri++] = acpi_ec_read_data(ec);
677 if (t->rlen == t->ri) {
678 ec_transaction_transition(ec, ACPI_EC_COMMAND_COMPLETE);
679 if (t->command == ACPI_EC_COMMAND_QUERY)
680 ec_dbg_evt("Command(%s) completed by hardware",
681 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY));
682 wakeup = true;
683 }
684 } else
685 goto err;
686 } else if (t->wlen == t->wi &&
687 (status & ACPI_EC_FLAG_IBF) == 0) {
688 ec_transaction_transition(ec, ACPI_EC_COMMAND_COMPLETE);
689 wakeup = true;
690 }
691 goto out;
692 } else {
693 if (EC_FLAGS_QUERY_HANDSHAKE &&
694 !(status & ACPI_EC_FLAG_SCI) &&
695 (t->command == ACPI_EC_COMMAND_QUERY)) {
696 ec_transaction_transition(ec, ACPI_EC_COMMAND_POLL);
697 t->rdata[t->ri++] = 0x00;
698 ec_transaction_transition(ec, ACPI_EC_COMMAND_COMPLETE);
699 ec_dbg_evt("Command(%s) completed by software",
700 acpi_ec_cmd_string(ACPI_EC_COMMAND_QUERY));
701 wakeup = true;
702 } else if ((status & ACPI_EC_FLAG_IBF) == 0) {
703 acpi_ec_write_cmd(ec, t->command);
704 ec_transaction_transition(ec, ACPI_EC_COMMAND_POLL);
705 } else
706 goto err;
707 goto out;
708 }
709err:
710 /*
711 * If SCI bit is set, then don't think it's a false IRQ
712 * otherwise will take a not handled IRQ as a false one.
713 */
714 if (!(status & ACPI_EC_FLAG_SCI)) {
715 if (in_interrupt() && t) {
716 if (t->irq_count < ec_storm_threshold)
717 ++t->irq_count;
718 /* Allow triggering on 0 threshold */
719 if (t->irq_count == ec_storm_threshold)
720 acpi_ec_mask_gpe(ec);
721 }
722 }
723out:
724 if (status & ACPI_EC_FLAG_SCI)
725 acpi_ec_submit_query(ec);
726 if (wakeup && in_interrupt())
727 wake_up(&ec->wait);
728}
729
730static void start_transaction(struct acpi_ec *ec)
731{
732 ec->curr->irq_count = ec->curr->wi = ec->curr->ri = 0;
733 ec->curr->flags = 0;
734}
735
736static int ec_guard(struct acpi_ec *ec)
737{
738 unsigned long guard = usecs_to_jiffies(ec->polling_guard);
739 unsigned long timeout = ec->timestamp + guard;
740
741 /* Ensure guarding period before polling EC status */
742 do {
743 if (ec->busy_polling) {
744 /* Perform busy polling */
745 if (ec_transaction_completed(ec))
746 return 0;
747 udelay(jiffies_to_usecs(guard));
748 } else {
749 /*
750 * Perform wait polling
751 * 1. Wait the transaction to be completed by the
752 * GPE handler after the transaction enters
753 * ACPI_EC_COMMAND_POLL state.
754 * 2. A special guarding logic is also required
755 * for event clearing mode "event" before the
756 * transaction enters ACPI_EC_COMMAND_POLL
757 * state.
758 */
759 if (!ec_transaction_polled(ec) &&
760 !acpi_ec_guard_event(ec))
761 break;
762 if (wait_event_timeout(ec->wait,
763 ec_transaction_completed(ec),
764 guard))
765 return 0;
766 }
767 } while (time_before(jiffies, timeout));
768 return -ETIME;
769}
770
771static int ec_poll(struct acpi_ec *ec)
772{
773 unsigned long flags;
774 int repeat = 5; /* number of command restarts */
775
776 while (repeat--) {
777 unsigned long delay = jiffies +
778 msecs_to_jiffies(ec_delay);
779 do {
780 if (!ec_guard(ec))
781 return 0;
782 spin_lock_irqsave(&ec->lock, flags);
783 advance_transaction(ec);
784 spin_unlock_irqrestore(&ec->lock, flags);
785 } while (time_before(jiffies, delay));
786 pr_debug("controller reset, restart transaction\n");
787 spin_lock_irqsave(&ec->lock, flags);
788 start_transaction(ec);
789 spin_unlock_irqrestore(&ec->lock, flags);
790 }
791 return -ETIME;
792}
793
794static int acpi_ec_transaction_unlocked(struct acpi_ec *ec,
795 struct transaction *t)
796{
797 unsigned long tmp;
798 int ret = 0;
799
800 /* start transaction */
801 spin_lock_irqsave(&ec->lock, tmp);
802 /* Enable GPE for command processing (IBF=0/OBF=1) */
803 if (!acpi_ec_submit_flushable_request(ec)) {
804 ret = -EINVAL;
805 goto unlock;
806 }
807 ec_dbg_ref(ec, "Increase command");
808 /* following two actions should be kept atomic */
809 ec->curr = t;
810 ec_dbg_req("Command(%s) started", acpi_ec_cmd_string(t->command));
811 start_transaction(ec);
812 spin_unlock_irqrestore(&ec->lock, tmp);
813
814 ret = ec_poll(ec);
815
816 spin_lock_irqsave(&ec->lock, tmp);
817 if (t->irq_count == ec_storm_threshold)
818 acpi_ec_unmask_gpe(ec);
819 ec_dbg_req("Command(%s) stopped", acpi_ec_cmd_string(t->command));
820 ec->curr = NULL;
821 /* Disable GPE for command processing (IBF=0/OBF=1) */
822 acpi_ec_complete_request(ec);
823 ec_dbg_ref(ec, "Decrease command");
824unlock:
825 spin_unlock_irqrestore(&ec->lock, tmp);
826 return ret;
827}
828
829static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t)
830{
831 int status;
832 u32 glk;
833
834 if (!ec || (!t) || (t->wlen && !t->wdata) || (t->rlen && !t->rdata))
835 return -EINVAL;
836 if (t->rdata)
837 memset(t->rdata, 0, t->rlen);
838
839 mutex_lock(&ec->mutex);
840 if (ec->global_lock) {
841 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
842 if (ACPI_FAILURE(status)) {
843 status = -ENODEV;
844 goto unlock;
845 }
846 }
847
848 status = acpi_ec_transaction_unlocked(ec, t);
849
850 if (ec->global_lock)
851 acpi_release_global_lock(glk);
852unlock:
853 mutex_unlock(&ec->mutex);
854 return status;
855}
856
857static int acpi_ec_burst_enable(struct acpi_ec *ec)
858{
859 u8 d;
860 struct transaction t = {.command = ACPI_EC_BURST_ENABLE,
861 .wdata = NULL, .rdata = &d,
862 .wlen = 0, .rlen = 1};
863
864 return acpi_ec_transaction(ec, &t);
865}
866
867static int acpi_ec_burst_disable(struct acpi_ec *ec)
868{
869 struct transaction t = {.command = ACPI_EC_BURST_DISABLE,
870 .wdata = NULL, .rdata = NULL,
871 .wlen = 0, .rlen = 0};
872
873 return (acpi_ec_read_status(ec) & ACPI_EC_FLAG_BURST) ?
874 acpi_ec_transaction(ec, &t) : 0;
875}
876
877static int acpi_ec_read(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(ec, &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);
898}
899
900int ec_read(u8 addr, u8 *val)
901{
902 int err;
903 u8 temp_data;
904
905 if (!first_ec)
906 return -ENODEV;
907
908 err = acpi_ec_read(first_ec, addr, &temp_data);
909
910 if (!err) {
911 *val = temp_data;
912 return 0;
913 }
914 return err;
915}
916EXPORT_SYMBOL(ec_read);
917
918int ec_write(u8 addr, u8 val)
919{
920 int err;
921
922 if (!first_ec)
923 return -ENODEV;
924
925 err = acpi_ec_write(first_ec, addr, val);
926
927 return err;
928}
929EXPORT_SYMBOL(ec_write);
930
931int ec_transaction(u8 command,
932 const u8 *wdata, unsigned wdata_len,
933 u8 *rdata, unsigned rdata_len)
934{
935 struct transaction t = {.command = command,
936 .wdata = wdata, .rdata = rdata,
937 .wlen = wdata_len, .rlen = rdata_len};
938
939 if (!first_ec)
940 return -ENODEV;
941
942 return acpi_ec_transaction(first_ec, &t);
943}
944EXPORT_SYMBOL(ec_transaction);
945
946/* Get the handle to the EC device */
947acpi_handle ec_get_handle(void)
948{
949 if (!first_ec)
950 return NULL;
951 return first_ec->handle;
952}
953EXPORT_SYMBOL(ec_get_handle);
954
955static void acpi_ec_start(struct acpi_ec *ec, bool resuming)
956{
957 unsigned long flags;
958
959 spin_lock_irqsave(&ec->lock, flags);
960 if (!test_and_set_bit(EC_FLAGS_STARTED, &ec->flags)) {
961 ec_dbg_drv("Starting EC");
962 /* Enable GPE for event processing (SCI_EVT=1) */
963 if (!resuming) {
964 acpi_ec_submit_request(ec);
965 ec_dbg_ref(ec, "Increase driver");
966 }
967 ec_log_drv("EC started");
968 }
969 spin_unlock_irqrestore(&ec->lock, flags);
970}
971
972static bool acpi_ec_stopped(struct acpi_ec *ec)
973{
974 unsigned long flags;
975 bool flushed;
976
977 spin_lock_irqsave(&ec->lock, flags);
978 flushed = acpi_ec_flushed(ec);
979 spin_unlock_irqrestore(&ec->lock, flags);
980 return flushed;
981}
982
983static void acpi_ec_stop(struct acpi_ec *ec, bool suspending)
984{
985 unsigned long flags;
986
987 spin_lock_irqsave(&ec->lock, flags);
988 if (acpi_ec_started(ec)) {
989 ec_dbg_drv("Stopping EC");
990 set_bit(EC_FLAGS_STOPPED, &ec->flags);
991 spin_unlock_irqrestore(&ec->lock, flags);
992 wait_event(ec->wait, acpi_ec_stopped(ec));
993 spin_lock_irqsave(&ec->lock, flags);
994 /* Disable GPE for event processing (SCI_EVT=1) */
995 if (!suspending) {
996 acpi_ec_complete_request(ec);
997 ec_dbg_ref(ec, "Decrease driver");
998 } else if (!ec_freeze_events)
999 __acpi_ec_disable_event(ec);
1000 clear_bit(EC_FLAGS_STARTED, &ec->flags);
1001 clear_bit(EC_FLAGS_STOPPED, &ec->flags);
1002 ec_log_drv("EC stopped");
1003 }
1004 spin_unlock_irqrestore(&ec->lock, flags);
1005}
1006
1007static void acpi_ec_enter_noirq(struct acpi_ec *ec)
1008{
1009 unsigned long flags;
1010
1011 spin_lock_irqsave(&ec->lock, flags);
1012 ec->busy_polling = true;
1013 ec->polling_guard = 0;
1014 ec_log_drv("interrupt blocked");
1015 spin_unlock_irqrestore(&ec->lock, flags);
1016}
1017
1018static void acpi_ec_leave_noirq(struct acpi_ec *ec)
1019{
1020 unsigned long flags;
1021
1022 spin_lock_irqsave(&ec->lock, flags);
1023 ec->busy_polling = ec_busy_polling;
1024 ec->polling_guard = ec_polling_guard;
1025 ec_log_drv("interrupt unblocked");
1026 spin_unlock_irqrestore(&ec->lock, flags);
1027}
1028
1029void acpi_ec_block_transactions(void)
1030{
1031 struct acpi_ec *ec = first_ec;
1032
1033 if (!ec)
1034 return;
1035
1036 mutex_lock(&ec->mutex);
1037 /* Prevent transactions from being carried out */
1038 acpi_ec_stop(ec, true);
1039 mutex_unlock(&ec->mutex);
1040}
1041
1042void acpi_ec_unblock_transactions(void)
1043{
1044 /*
1045 * Allow transactions to happen again (this function is called from
1046 * atomic context during wakeup, so we don't need to acquire the mutex).
1047 */
1048 if (first_ec)
1049 acpi_ec_start(first_ec, true);
1050}
1051
1052/* --------------------------------------------------------------------------
1053 Event Management
1054 -------------------------------------------------------------------------- */
1055static struct acpi_ec_query_handler *
1056acpi_ec_get_query_handler(struct acpi_ec_query_handler *handler)
1057{
1058 if (handler)
1059 kref_get(&handler->kref);
1060 return handler;
1061}
1062
1063static struct acpi_ec_query_handler *
1064acpi_ec_get_query_handler_by_value(struct acpi_ec *ec, u8 value)
1065{
1066 struct acpi_ec_query_handler *handler;
1067 bool found = false;
1068
1069 mutex_lock(&ec->mutex);
1070 list_for_each_entry(handler, &ec->list, node) {
1071 if (value == handler->query_bit) {
1072 found = true;
1073 break;
1074 }
1075 }
1076 mutex_unlock(&ec->mutex);
1077 return found ? acpi_ec_get_query_handler(handler) : NULL;
1078}
1079
1080static void acpi_ec_query_handler_release(struct kref *kref)
1081{
1082 struct acpi_ec_query_handler *handler =
1083 container_of(kref, struct acpi_ec_query_handler, kref);
1084
1085 kfree(handler);
1086}
1087
1088static void acpi_ec_put_query_handler(struct acpi_ec_query_handler *handler)
1089{
1090 kref_put(&handler->kref, acpi_ec_query_handler_release);
1091}
1092
1093int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
1094 acpi_handle handle, acpi_ec_query_func func,
1095 void *data)
1096{
1097 struct acpi_ec_query_handler *handler =
1098 kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL);
1099
1100 if (!handler)
1101 return -ENOMEM;
1102
1103 handler->query_bit = query_bit;
1104 handler->handle = handle;
1105 handler->func = func;
1106 handler->data = data;
1107 mutex_lock(&ec->mutex);
1108 kref_init(&handler->kref);
1109 list_add(&handler->node, &ec->list);
1110 mutex_unlock(&ec->mutex);
1111 return 0;
1112}
1113EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler);
1114
1115static void acpi_ec_remove_query_handlers(struct acpi_ec *ec,
1116 bool remove_all, u8 query_bit)
1117{
1118 struct acpi_ec_query_handler *handler, *tmp;
1119 LIST_HEAD(free_list);
1120
1121 mutex_lock(&ec->mutex);
1122 list_for_each_entry_safe(handler, tmp, &ec->list, node) {
1123 if (remove_all || query_bit == handler->query_bit) {
1124 list_del_init(&handler->node);
1125 list_add(&handler->node, &free_list);
1126 }
1127 }
1128 mutex_unlock(&ec->mutex);
1129 list_for_each_entry_safe(handler, tmp, &free_list, node)
1130 acpi_ec_put_query_handler(handler);
1131}
1132
1133void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit)
1134{
1135 acpi_ec_remove_query_handlers(ec, false, query_bit);
1136}
1137EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler);
1138
1139static struct acpi_ec_query *acpi_ec_create_query(u8 *pval)
1140{
1141 struct acpi_ec_query *q;
1142 struct transaction *t;
1143
1144 q = kzalloc(sizeof (struct acpi_ec_query), GFP_KERNEL);
1145 if (!q)
1146 return NULL;
1147 INIT_WORK(&q->work, acpi_ec_event_processor);
1148 t = &q->transaction;
1149 t->command = ACPI_EC_COMMAND_QUERY;
1150 t->rdata = pval;
1151 t->rlen = 1;
1152 return q;
1153}
1154
1155static void acpi_ec_delete_query(struct acpi_ec_query *q)
1156{
1157 if (q) {
1158 if (q->handler)
1159 acpi_ec_put_query_handler(q->handler);
1160 kfree(q);
1161 }
1162}
1163
1164static void acpi_ec_event_processor(struct work_struct *work)
1165{
1166 struct acpi_ec_query *q = container_of(work, struct acpi_ec_query, work);
1167 struct acpi_ec_query_handler *handler = q->handler;
1168
1169 ec_dbg_evt("Query(0x%02x) started", handler->query_bit);
1170 if (handler->func)
1171 handler->func(handler->data);
1172 else if (handler->handle)
1173 acpi_evaluate_object(handler->handle, NULL, NULL, NULL);
1174 ec_dbg_evt("Query(0x%02x) stopped", handler->query_bit);
1175 acpi_ec_delete_query(q);
1176}
1177
1178static int acpi_ec_query(struct acpi_ec *ec, u8 *data)
1179{
1180 u8 value = 0;
1181 int result;
1182 struct acpi_ec_query *q;
1183
1184 q = acpi_ec_create_query(&value);
1185 if (!q)
1186 return -ENOMEM;
1187
1188 /*
1189 * Query the EC to find out which _Qxx method we need to evaluate.
1190 * Note that successful completion of the query causes the ACPI_EC_SCI
1191 * bit to be cleared (and thus clearing the interrupt source).
1192 */
1193 result = acpi_ec_transaction(ec, &q->transaction);
1194 if (!value)
1195 result = -ENODATA;
1196 if (result)
1197 goto err_exit;
1198
1199 q->handler = acpi_ec_get_query_handler_by_value(ec, value);
1200 if (!q->handler) {
1201 result = -ENODATA;
1202 goto err_exit;
1203 }
1204
1205 /*
1206 * It is reported that _Qxx are evaluated in a parallel way on
1207 * Windows:
1208 * https://bugzilla.kernel.org/show_bug.cgi?id=94411
1209 *
1210 * Put this log entry before schedule_work() in order to make
1211 * it appearing before any other log entries occurred during the
1212 * work queue execution.
1213 */
1214 ec_dbg_evt("Query(0x%02x) scheduled", value);
1215 if (!queue_work(ec_query_wq, &q->work)) {
1216 ec_dbg_evt("Query(0x%02x) overlapped", value);
1217 result = -EBUSY;
1218 }
1219
1220err_exit:
1221 if (result)
1222 acpi_ec_delete_query(q);
1223 if (data)
1224 *data = value;
1225 return result;
1226}
1227
1228static void acpi_ec_check_event(struct acpi_ec *ec)
1229{
1230 unsigned long flags;
1231
1232 if (ec_event_clearing == ACPI_EC_EVT_TIMING_EVENT) {
1233 if (ec_guard(ec)) {
1234 spin_lock_irqsave(&ec->lock, flags);
1235 /*
1236 * Take care of the SCI_EVT unless no one else is
1237 * taking care of it.
1238 */
1239 if (!ec->curr)
1240 advance_transaction(ec);
1241 spin_unlock_irqrestore(&ec->lock, flags);
1242 }
1243 }
1244}
1245
1246static void acpi_ec_event_handler(struct work_struct *work)
1247{
1248 unsigned long flags;
1249 struct acpi_ec *ec = container_of(work, struct acpi_ec, work);
1250
1251 ec_dbg_evt("Event started");
1252
1253 spin_lock_irqsave(&ec->lock, flags);
1254 while (ec->nr_pending_queries) {
1255 spin_unlock_irqrestore(&ec->lock, flags);
1256 (void)acpi_ec_query(ec, NULL);
1257 spin_lock_irqsave(&ec->lock, flags);
1258 ec->nr_pending_queries--;
1259 /*
1260 * Before exit, make sure that this work item can be
1261 * scheduled again. There might be QR_EC failures, leaving
1262 * EC_FLAGS_QUERY_PENDING uncleared and preventing this work
1263 * item from being scheduled again.
1264 */
1265 if (!ec->nr_pending_queries) {
1266 if (ec_event_clearing == ACPI_EC_EVT_TIMING_STATUS ||
1267 ec_event_clearing == ACPI_EC_EVT_TIMING_QUERY)
1268 acpi_ec_complete_query(ec);
1269 }
1270 }
1271 spin_unlock_irqrestore(&ec->lock, flags);
1272
1273 ec_dbg_evt("Event stopped");
1274
1275 acpi_ec_check_event(ec);
1276}
1277
1278static u32 acpi_ec_gpe_handler(acpi_handle gpe_device,
1279 u32 gpe_number, void *data)
1280{
1281 unsigned long flags;
1282 struct acpi_ec *ec = data;
1283
1284 spin_lock_irqsave(&ec->lock, flags);
1285 advance_transaction(ec);
1286 spin_unlock_irqrestore(&ec->lock, flags);
1287 return ACPI_INTERRUPT_HANDLED;
1288}
1289
1290/* --------------------------------------------------------------------------
1291 * Address Space Management
1292 * -------------------------------------------------------------------------- */
1293
1294static acpi_status
1295acpi_ec_space_handler(u32 function, acpi_physical_address address,
1296 u32 bits, u64 *value64,
1297 void *handler_context, void *region_context)
1298{
1299 struct acpi_ec *ec = handler_context;
1300 int result = 0, i, bytes = bits / 8;
1301 u8 *value = (u8 *)value64;
1302
1303 if ((address > 0xFF) || !value || !handler_context)
1304 return AE_BAD_PARAMETER;
1305
1306 if (function != ACPI_READ && function != ACPI_WRITE)
1307 return AE_BAD_PARAMETER;
1308
1309 if (ec->busy_polling || bits > 8)
1310 acpi_ec_burst_enable(ec);
1311
1312 for (i = 0; i < bytes; ++i, ++address, ++value)
1313 result = (function == ACPI_READ) ?
1314 acpi_ec_read(ec, address, value) :
1315 acpi_ec_write(ec, address, *value);
1316
1317 if (ec->busy_polling || bits > 8)
1318 acpi_ec_burst_disable(ec);
1319
1320 switch (result) {
1321 case -EINVAL:
1322 return AE_BAD_PARAMETER;
1323 case -ENODEV:
1324 return AE_NOT_FOUND;
1325 case -ETIME:
1326 return AE_TIME;
1327 default:
1328 return AE_OK;
1329 }
1330}
1331
1332/* --------------------------------------------------------------------------
1333 * Driver Interface
1334 * -------------------------------------------------------------------------- */
1335
1336static acpi_status
1337ec_parse_io_ports(struct acpi_resource *resource, void *context);
1338
1339static void acpi_ec_free(struct acpi_ec *ec)
1340{
1341 if (first_ec == ec)
1342 first_ec = NULL;
1343 if (boot_ec == ec)
1344 boot_ec = NULL;
1345 kfree(ec);
1346}
1347
1348static struct acpi_ec *acpi_ec_alloc(void)
1349{
1350 struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
1351
1352 if (!ec)
1353 return NULL;
1354 mutex_init(&ec->mutex);
1355 init_waitqueue_head(&ec->wait);
1356 INIT_LIST_HEAD(&ec->list);
1357 spin_lock_init(&ec->lock);
1358 INIT_WORK(&ec->work, acpi_ec_event_handler);
1359 ec->timestamp = jiffies;
1360 ec->busy_polling = true;
1361 ec->polling_guard = 0;
1362 return ec;
1363}
1364
1365static acpi_status
1366acpi_ec_register_query_methods(acpi_handle handle, u32 level,
1367 void *context, void **return_value)
1368{
1369 char node_name[5];
1370 struct acpi_buffer buffer = { sizeof(node_name), node_name };
1371 struct acpi_ec *ec = context;
1372 int value = 0;
1373 acpi_status status;
1374
1375 status = acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
1376
1377 if (ACPI_SUCCESS(status) && sscanf(node_name, "_Q%x", &value) == 1)
1378 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL);
1379 return AE_OK;
1380}
1381
1382static acpi_status
1383ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
1384{
1385 acpi_status status;
1386 unsigned long long tmp = 0;
1387 struct acpi_ec *ec = context;
1388
1389 /* clear addr values, ec_parse_io_ports depend on it */
1390 ec->command_addr = ec->data_addr = 0;
1391
1392 status = acpi_walk_resources(handle, METHOD_NAME__CRS,
1393 ec_parse_io_ports, ec);
1394 if (ACPI_FAILURE(status))
1395 return status;
1396 if (ec->data_addr == 0 || ec->command_addr == 0)
1397 return AE_OK;
1398
1399 if (boot_ec && boot_ec_is_ecdt && EC_FLAGS_IGNORE_DSDT_GPE) {
1400 /*
1401 * Always inherit the GPE number setting from the ECDT
1402 * EC.
1403 */
1404 ec->gpe = boot_ec->gpe;
1405 } else {
1406 /* Get GPE bit assignment (EC events). */
1407 /* TODO: Add support for _GPE returning a package */
1408 status = acpi_evaluate_integer(handle, "_GPE", NULL, &tmp);
1409 if (ACPI_FAILURE(status))
1410 return status;
1411 ec->gpe = tmp;
1412 }
1413 /* Use the global lock for all EC transactions? */
1414 tmp = 0;
1415 acpi_evaluate_integer(handle, "_GLK", NULL, &tmp);
1416 ec->global_lock = tmp;
1417 ec->handle = handle;
1418 return AE_CTRL_TERMINATE;
1419}
1420
1421/*
1422 * Note: This function returns an error code only when the address space
1423 * handler is not installed, which means "not able to handle
1424 * transactions".
1425 */
1426static int ec_install_handlers(struct acpi_ec *ec, bool handle_events)
1427{
1428 acpi_status status;
1429
1430 acpi_ec_start(ec, false);
1431
1432 if (!test_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags)) {
1433 acpi_ec_enter_noirq(ec);
1434 status = acpi_install_address_space_handler(ec->handle,
1435 ACPI_ADR_SPACE_EC,
1436 &acpi_ec_space_handler,
1437 NULL, ec);
1438 if (ACPI_FAILURE(status)) {
1439 if (status == AE_NOT_FOUND) {
1440 /*
1441 * Maybe OS fails in evaluating the _REG
1442 * object. The AE_NOT_FOUND error will be
1443 * ignored and OS * continue to initialize
1444 * EC.
1445 */
1446 pr_err("Fail in evaluating the _REG object"
1447 " of EC device. Broken bios is suspected.\n");
1448 } else {
1449 acpi_ec_stop(ec, false);
1450 return -ENODEV;
1451 }
1452 }
1453 set_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags);
1454 }
1455
1456 if (!handle_events)
1457 return 0;
1458
1459 if (!test_bit(EC_FLAGS_EVT_HANDLER_INSTALLED, &ec->flags)) {
1460 /* Find and register all query methods */
1461 acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1,
1462 acpi_ec_register_query_methods,
1463 NULL, ec, NULL);
1464 set_bit(EC_FLAGS_EVT_HANDLER_INSTALLED, &ec->flags);
1465 }
1466 if (!test_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags)) {
1467 status = acpi_install_gpe_raw_handler(NULL, ec->gpe,
1468 ACPI_GPE_EDGE_TRIGGERED,
1469 &acpi_ec_gpe_handler, ec);
1470 /* This is not fatal as we can poll EC events */
1471 if (ACPI_SUCCESS(status)) {
1472 set_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags);
1473 acpi_ec_leave_noirq(ec);
1474 if (test_bit(EC_FLAGS_STARTED, &ec->flags) &&
1475 ec->reference_count >= 1)
1476 acpi_ec_enable_gpe(ec, true);
1477 }
1478 }
1479 /* EC is fully operational, allow queries */
1480 acpi_ec_enable_event(ec);
1481
1482 return 0;
1483}
1484
1485static void ec_remove_handlers(struct acpi_ec *ec)
1486{
1487 if (test_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags)) {
1488 if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle,
1489 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler)))
1490 pr_err("failed to remove space handler\n");
1491 clear_bit(EC_FLAGS_EC_HANDLER_INSTALLED, &ec->flags);
1492 }
1493
1494 /*
1495 * Stops handling the EC transactions after removing the operation
1496 * region handler. This is required because _REG(DISCONNECT)
1497 * invoked during the removal can result in new EC transactions.
1498 *
1499 * Flushes the EC requests and thus disables the GPE before
1500 * removing the GPE handler. This is required by the current ACPICA
1501 * GPE core. ACPICA GPE core will automatically disable a GPE when
1502 * it is indicated but there is no way to handle it. So the drivers
1503 * must disable the GPEs prior to removing the GPE handlers.
1504 */
1505 acpi_ec_stop(ec, false);
1506
1507 if (test_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags)) {
1508 if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe,
1509 &acpi_ec_gpe_handler)))
1510 pr_err("failed to remove gpe handler\n");
1511 clear_bit(EC_FLAGS_GPE_HANDLER_INSTALLED, &ec->flags);
1512 }
1513 if (test_bit(EC_FLAGS_EVT_HANDLER_INSTALLED, &ec->flags)) {
1514 acpi_ec_remove_query_handlers(ec, true, 0);
1515 clear_bit(EC_FLAGS_EVT_HANDLER_INSTALLED, &ec->flags);
1516 }
1517}
1518
1519static int acpi_ec_setup(struct acpi_ec *ec, bool handle_events)
1520{
1521 int ret;
1522
1523 ret = ec_install_handlers(ec, handle_events);
1524 if (ret)
1525 return ret;
1526
1527 /* First EC capable of handling transactions */
1528 if (!first_ec) {
1529 first_ec = ec;
1530 acpi_handle_info(first_ec->handle, "Used as first EC\n");
1531 }
1532
1533 acpi_handle_info(ec->handle,
1534 "GPE=0x%x, EC_CMD/EC_SC=0x%lx, EC_DATA=0x%lx\n",
1535 ec->gpe, ec->command_addr, ec->data_addr);
1536 return ret;
1537}
1538
1539static bool acpi_ec_ecdt_get_handle(acpi_handle *phandle)
1540{
1541 struct acpi_table_ecdt *ecdt_ptr;
1542 acpi_status status;
1543 acpi_handle handle;
1544
1545 status = acpi_get_table(ACPI_SIG_ECDT, 1,
1546 (struct acpi_table_header **)&ecdt_ptr);
1547 if (ACPI_FAILURE(status))
1548 return false;
1549
1550 status = acpi_get_handle(NULL, ecdt_ptr->id, &handle);
1551 if (ACPI_FAILURE(status))
1552 return false;
1553
1554 *phandle = handle;
1555 return true;
1556}
1557
1558static int acpi_ec_add(struct acpi_device *device)
1559{
1560 struct acpi_ec *ec = NULL;
1561 bool dep_update = true;
1562 acpi_status status;
1563 int ret;
1564
1565 strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
1566 strcpy(acpi_device_class(device), ACPI_EC_CLASS);
1567
1568 if (!strcmp(acpi_device_hid(device), ACPI_ECDT_HID)) {
1569 boot_ec_is_ecdt = true;
1570 ec = boot_ec;
1571 dep_update = false;
1572 } else {
1573 ec = acpi_ec_alloc();
1574 if (!ec)
1575 return -ENOMEM;
1576
1577 status = ec_parse_device(device->handle, 0, ec, NULL);
1578 if (status != AE_CTRL_TERMINATE) {
1579 ret = -EINVAL;
1580 goto err_alloc;
1581 }
1582
1583 if (boot_ec && ec->command_addr == boot_ec->command_addr &&
1584 ec->data_addr == boot_ec->data_addr) {
1585 boot_ec_is_ecdt = false;
1586 /*
1587 * Trust PNP0C09 namespace location rather than
1588 * ECDT ID. But trust ECDT GPE rather than _GPE
1589 * because of ASUS quirks, so do not change
1590 * boot_ec->gpe to ec->gpe.
1591 */
1592 boot_ec->handle = ec->handle;
1593 acpi_handle_debug(ec->handle, "duplicated.\n");
1594 acpi_ec_free(ec);
1595 ec = boot_ec;
1596 }
1597 }
1598
1599 ret = acpi_ec_setup(ec, true);
1600 if (ret)
1601 goto err_query;
1602
1603 if (ec == boot_ec)
1604 acpi_handle_info(boot_ec->handle,
1605 "Boot %s EC used to handle transactions and events\n",
1606 boot_ec_is_ecdt ? "ECDT" : "DSDT");
1607
1608 device->driver_data = ec;
1609
1610 ret = !!request_region(ec->data_addr, 1, "EC data");
1611 WARN(!ret, "Could not request EC data io port 0x%lx", ec->data_addr);
1612 ret = !!request_region(ec->command_addr, 1, "EC cmd");
1613 WARN(!ret, "Could not request EC cmd io port 0x%lx", ec->command_addr);
1614
1615 if (dep_update) {
1616 /* Reprobe devices depending on the EC */
1617 acpi_walk_dep_device_list(ec->handle);
1618 }
1619 acpi_handle_debug(ec->handle, "enumerated.\n");
1620 return 0;
1621
1622err_query:
1623 if (ec != boot_ec)
1624 acpi_ec_remove_query_handlers(ec, true, 0);
1625err_alloc:
1626 if (ec != boot_ec)
1627 acpi_ec_free(ec);
1628 return ret;
1629}
1630
1631static int acpi_ec_remove(struct acpi_device *device)
1632{
1633 struct acpi_ec *ec;
1634
1635 if (!device)
1636 return -EINVAL;
1637
1638 ec = acpi_driver_data(device);
1639 release_region(ec->data_addr, 1);
1640 release_region(ec->command_addr, 1);
1641 device->driver_data = NULL;
1642 if (ec != boot_ec) {
1643 ec_remove_handlers(ec);
1644 acpi_ec_free(ec);
1645 }
1646 return 0;
1647}
1648
1649static acpi_status
1650ec_parse_io_ports(struct acpi_resource *resource, void *context)
1651{
1652 struct acpi_ec *ec = context;
1653
1654 if (resource->type != ACPI_RESOURCE_TYPE_IO)
1655 return AE_OK;
1656
1657 /*
1658 * The first address region returned is the data port, and
1659 * the second address region returned is the status/command
1660 * port.
1661 */
1662 if (ec->data_addr == 0)
1663 ec->data_addr = resource->data.io.minimum;
1664 else if (ec->command_addr == 0)
1665 ec->command_addr = resource->data.io.minimum;
1666 else
1667 return AE_CTRL_TERMINATE;
1668
1669 return AE_OK;
1670}
1671
1672static const struct acpi_device_id ec_device_ids[] = {
1673 {"PNP0C09", 0},
1674 {ACPI_ECDT_HID, 0},
1675 {"", 0},
1676};
1677
1678/*
1679 * This function is not Windows-compatible as Windows never enumerates the
1680 * namespace EC before the main ACPI device enumeration process. It is
1681 * retained for historical reason and will be deprecated in the future.
1682 */
1683void __init acpi_ec_dsdt_probe(void)
1684{
1685 struct acpi_ec *ec;
1686 acpi_status status;
1687 int ret;
1688
1689 /*
1690 * If a platform has ECDT, there is no need to proceed as the
1691 * following probe is not a part of the ACPI device enumeration,
1692 * executing _STA is not safe, and thus this probe may risk of
1693 * picking up an invalid EC device.
1694 */
1695 if (boot_ec)
1696 return;
1697
1698 ec = acpi_ec_alloc();
1699 if (!ec)
1700 return;
1701
1702 /*
1703 * At this point, the namespace is initialized, so start to find
1704 * the namespace objects.
1705 */
1706 status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device, ec, NULL);
1707 if (ACPI_FAILURE(status) || !ec->handle) {
1708 acpi_ec_free(ec);
1709 return;
1710 }
1711
1712 /*
1713 * When the DSDT EC is available, always re-configure boot EC to
1714 * have _REG evaluated. _REG can only be evaluated after the
1715 * namespace initialization.
1716 * At this point, the GPE is not fully initialized, so do not to
1717 * handle the events.
1718 */
1719 ret = acpi_ec_setup(ec, false);
1720 if (ret) {
1721 acpi_ec_free(ec);
1722 return;
1723 }
1724
1725 boot_ec = ec;
1726
1727 acpi_handle_info(ec->handle,
1728 "Boot DSDT EC used to handle transactions\n");
1729}
1730
1731/*
1732 * If the DSDT EC is not functioning, we still need to prepare a fully
1733 * functioning ECDT EC first in order to handle the events.
1734 * https://bugzilla.kernel.org/show_bug.cgi?id=115021
1735 */
1736static int __init acpi_ec_ecdt_start(void)
1737{
1738 acpi_handle handle;
1739
1740 if (!boot_ec)
1741 return -ENODEV;
1742 /* In case acpi_ec_ecdt_start() is called after acpi_ec_add() */
1743 if (!boot_ec_is_ecdt)
1744 return -ENODEV;
1745
1746 /*
1747 * At this point, the namespace and the GPE is initialized, so
1748 * start to find the namespace objects and handle the events.
1749 *
1750 * Note: ec->handle can be valid if this function is called after
1751 * acpi_ec_add(), hence the fast path.
1752 */
1753 if (boot_ec->handle == ACPI_ROOT_OBJECT) {
1754 if (!acpi_ec_ecdt_get_handle(&handle))
1755 return -ENODEV;
1756 boot_ec->handle = handle;
1757 }
1758
1759 /* Register to ACPI bus with PM ops attached */
1760 return acpi_bus_register_early_device(ACPI_BUS_TYPE_ECDT_EC);
1761}
1762
1763#if 0
1764/*
1765 * Some EC firmware variations refuses to respond QR_EC when SCI_EVT is not
1766 * set, for which case, we complete the QR_EC without issuing it to the
1767 * firmware.
1768 * https://bugzilla.kernel.org/show_bug.cgi?id=82611
1769 * https://bugzilla.kernel.org/show_bug.cgi?id=97381
1770 */
1771static int ec_flag_query_handshake(const struct dmi_system_id *id)
1772{
1773 pr_debug("Detected the EC firmware requiring QR_EC issued when SCI_EVT set\n");
1774 EC_FLAGS_QUERY_HANDSHAKE = 1;
1775 return 0;
1776}
1777#endif
1778
1779/*
1780 * On some hardware it is necessary to clear events accumulated by the EC during
1781 * sleep. These ECs stop reporting GPEs until they are manually polled, if too
1782 * many events are accumulated. (e.g. Samsung Series 5/9 notebooks)
1783 *
1784 * https://bugzilla.kernel.org/show_bug.cgi?id=44161
1785 *
1786 * Ideally, the EC should also be instructed NOT to accumulate events during
1787 * sleep (which Windows seems to do somehow), but the interface to control this
1788 * behaviour is not known at this time.
1789 *
1790 * Models known to be affected are Samsung 530Uxx/535Uxx/540Uxx/550Pxx/900Xxx,
1791 * however it is very likely that other Samsung models are affected.
1792 *
1793 * On systems which don't accumulate _Q events during sleep, this extra check
1794 * should be harmless.
1795 */
1796static int ec_clear_on_resume(const struct dmi_system_id *id)
1797{
1798 pr_debug("Detected system needing EC poll on resume.\n");
1799 EC_FLAGS_CLEAR_ON_RESUME = 1;
1800 ec_event_clearing = ACPI_EC_EVT_TIMING_STATUS;
1801 return 0;
1802}
1803
1804/*
1805 * Some ECDTs contain wrong register addresses.
1806 * MSI MS-171F
1807 * https://bugzilla.kernel.org/show_bug.cgi?id=12461
1808 */
1809static int ec_correct_ecdt(const struct dmi_system_id *id)
1810{
1811 pr_debug("Detected system needing ECDT address correction.\n");
1812 EC_FLAGS_CORRECT_ECDT = 1;
1813 return 0;
1814}
1815
1816/*
1817 * Some DSDTs contain wrong GPE setting.
1818 * Asus FX502VD/VE, GL702VMK, X550VXK, X580VD
1819 * https://bugzilla.kernel.org/show_bug.cgi?id=195651
1820 */
1821static int ec_honor_ecdt_gpe(const struct dmi_system_id *id)
1822{
1823 pr_debug("Detected system needing ignore DSDT GPE setting.\n");
1824 EC_FLAGS_IGNORE_DSDT_GPE = 1;
1825 return 0;
1826}
1827
1828static const struct dmi_system_id ec_dmi_table[] __initconst = {
1829 {
1830 ec_correct_ecdt, "MSI MS-171F", {
1831 DMI_MATCH(DMI_SYS_VENDOR, "Micro-Star"),
1832 DMI_MATCH(DMI_PRODUCT_NAME, "MS-171F"),}, NULL},
1833 {
1834 ec_honor_ecdt_gpe, "ASUS FX502VD", {
1835 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
1836 DMI_MATCH(DMI_PRODUCT_NAME, "FX502VD"),}, NULL},
1837 {
1838 ec_honor_ecdt_gpe, "ASUS FX502VE", {
1839 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
1840 DMI_MATCH(DMI_PRODUCT_NAME, "FX502VE"),}, NULL},
1841 {
1842 ec_honor_ecdt_gpe, "ASUS GL702VMK", {
1843 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
1844 DMI_MATCH(DMI_PRODUCT_NAME, "GL702VMK"),}, NULL},
1845 {
1846 ec_honor_ecdt_gpe, "ASUS X550VXK", {
1847 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
1848 DMI_MATCH(DMI_PRODUCT_NAME, "X550VXK"),}, NULL},
1849 {
1850 ec_honor_ecdt_gpe, "ASUS X580VD", {
1851 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
1852 DMI_MATCH(DMI_PRODUCT_NAME, "X580VD"),}, NULL},
1853 {
1854 ec_clear_on_resume, "Samsung hardware", {
1855 DMI_MATCH(DMI_SYS_VENDOR, "SAMSUNG ELECTRONICS CO., LTD.")}, NULL},
1856 {},
1857};
1858
1859void __init acpi_ec_ecdt_probe(void)
1860{
1861 struct acpi_table_ecdt *ecdt_ptr;
1862 struct acpi_ec *ec;
1863 acpi_status status;
1864 int ret;
1865
1866 /* Generate a boot ec context. */
1867 dmi_check_system(ec_dmi_table);
1868 status = acpi_get_table(ACPI_SIG_ECDT, 1,
1869 (struct acpi_table_header **)&ecdt_ptr);
1870 if (ACPI_FAILURE(status))
1871 return;
1872
1873 if (!ecdt_ptr->control.address || !ecdt_ptr->data.address) {
1874 /*
1875 * Asus X50GL:
1876 * https://bugzilla.kernel.org/show_bug.cgi?id=11880
1877 */
1878 return;
1879 }
1880
1881 ec = acpi_ec_alloc();
1882 if (!ec)
1883 return;
1884
1885 if (EC_FLAGS_CORRECT_ECDT) {
1886 ec->command_addr = ecdt_ptr->data.address;
1887 ec->data_addr = ecdt_ptr->control.address;
1888 } else {
1889 ec->command_addr = ecdt_ptr->control.address;
1890 ec->data_addr = ecdt_ptr->data.address;
1891 }
1892 ec->gpe = ecdt_ptr->gpe;
1893 ec->handle = ACPI_ROOT_OBJECT;
1894
1895 /*
1896 * At this point, the namespace is not initialized, so do not find
1897 * the namespace objects, or handle the events.
1898 */
1899 ret = acpi_ec_setup(ec, false);
1900 if (ret) {
1901 acpi_ec_free(ec);
1902 return;
1903 }
1904
1905 boot_ec = ec;
1906 boot_ec_is_ecdt = true;
1907
1908 pr_info("Boot ECDT EC used to handle transactions\n");
1909}
1910
1911#ifdef CONFIG_PM_SLEEP
1912static int acpi_ec_suspend(struct device *dev)
1913{
1914 struct acpi_ec *ec =
1915 acpi_driver_data(to_acpi_device(dev));
1916
1917 if (!pm_suspend_no_platform() && ec_freeze_events)
1918 acpi_ec_disable_event(ec);
1919 return 0;
1920}
1921
1922static int acpi_ec_suspend_noirq(struct device *dev)
1923{
1924 struct acpi_ec *ec = acpi_driver_data(to_acpi_device(dev));
1925
1926 /*
1927 * The SCI handler doesn't run at this point, so the GPE can be
1928 * masked at the low level without side effects.
1929 */
1930 if (ec_no_wakeup && test_bit(EC_FLAGS_STARTED, &ec->flags) &&
1931 ec->reference_count >= 1)
1932 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_DISABLE);
1933
1934 acpi_ec_enter_noirq(ec);
1935
1936 return 0;
1937}
1938
1939static int acpi_ec_resume_noirq(struct device *dev)
1940{
1941 struct acpi_ec *ec = acpi_driver_data(to_acpi_device(dev));
1942
1943 acpi_ec_leave_noirq(ec);
1944
1945 if (ec_no_wakeup && test_bit(EC_FLAGS_STARTED, &ec->flags) &&
1946 ec->reference_count >= 1)
1947 acpi_set_gpe(NULL, ec->gpe, ACPI_GPE_ENABLE);
1948
1949 return 0;
1950}
1951
1952static int acpi_ec_resume(struct device *dev)
1953{
1954 struct acpi_ec *ec =
1955 acpi_driver_data(to_acpi_device(dev));
1956
1957 acpi_ec_enable_event(ec);
1958 return 0;
1959}
1960
1961void acpi_ec_mark_gpe_for_wake(void)
1962{
1963 if (first_ec && !ec_no_wakeup)
1964 acpi_mark_gpe_for_wake(NULL, first_ec->gpe);
1965}
1966EXPORT_SYMBOL_GPL(acpi_ec_mark_gpe_for_wake);
1967
1968void acpi_ec_set_gpe_wake_mask(u8 action)
1969{
1970 if (pm_suspend_no_platform() && first_ec && !ec_no_wakeup)
1971 acpi_set_gpe_wake_mask(NULL, first_ec->gpe, action);
1972}
1973
1974bool acpi_ec_dispatch_gpe(void)
1975{
1976 u32 ret;
1977
1978 if (!first_ec)
1979 return false;
1980
1981 ret = acpi_dispatch_gpe(NULL, first_ec->gpe);
1982 if (ret == ACPI_INTERRUPT_HANDLED) {
1983 pm_pr_dbg("EC GPE dispatched\n");
1984 return true;
1985 }
1986 return false;
1987}
1988#endif /* CONFIG_PM_SLEEP */
1989
1990static const struct dev_pm_ops acpi_ec_pm = {
1991 SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(acpi_ec_suspend_noirq, acpi_ec_resume_noirq)
1992 SET_SYSTEM_SLEEP_PM_OPS(acpi_ec_suspend, acpi_ec_resume)
1993};
1994
1995static int param_set_event_clearing(const char *val,
1996 const struct kernel_param *kp)
1997{
1998 int result = 0;
1999
2000 if (!strncmp(val, "status", sizeof("status") - 1)) {
2001 ec_event_clearing = ACPI_EC_EVT_TIMING_STATUS;
2002 pr_info("Assuming SCI_EVT clearing on EC_SC accesses\n");
2003 } else if (!strncmp(val, "query", sizeof("query") - 1)) {
2004 ec_event_clearing = ACPI_EC_EVT_TIMING_QUERY;
2005 pr_info("Assuming SCI_EVT clearing on QR_EC writes\n");
2006 } else if (!strncmp(val, "event", sizeof("event") - 1)) {
2007 ec_event_clearing = ACPI_EC_EVT_TIMING_EVENT;
2008 pr_info("Assuming SCI_EVT clearing on event reads\n");
2009 } else
2010 result = -EINVAL;
2011 return result;
2012}
2013
2014static int param_get_event_clearing(char *buffer,
2015 const struct kernel_param *kp)
2016{
2017 switch (ec_event_clearing) {
2018 case ACPI_EC_EVT_TIMING_STATUS:
2019 return sprintf(buffer, "status");
2020 case ACPI_EC_EVT_TIMING_QUERY:
2021 return sprintf(buffer, "query");
2022 case ACPI_EC_EVT_TIMING_EVENT:
2023 return sprintf(buffer, "event");
2024 default:
2025 return sprintf(buffer, "invalid");
2026 }
2027 return 0;
2028}
2029
2030module_param_call(ec_event_clearing, param_set_event_clearing, param_get_event_clearing,
2031 NULL, 0644);
2032MODULE_PARM_DESC(ec_event_clearing, "Assumed SCI_EVT clearing timing");
2033
2034static struct acpi_driver acpi_ec_driver = {
2035 .name = "ec",
2036 .class = ACPI_EC_CLASS,
2037 .ids = ec_device_ids,
2038 .ops = {
2039 .add = acpi_ec_add,
2040 .remove = acpi_ec_remove,
2041 },
2042 .drv.pm = &acpi_ec_pm,
2043};
2044
2045static inline int acpi_ec_query_init(void)
2046{
2047 if (!ec_query_wq) {
2048 ec_query_wq = alloc_workqueue("kec_query", 0,
2049 ec_max_queries);
2050 if (!ec_query_wq)
2051 return -ENODEV;
2052 }
2053 return 0;
2054}
2055
2056static inline void acpi_ec_query_exit(void)
2057{
2058 if (ec_query_wq) {
2059 destroy_workqueue(ec_query_wq);
2060 ec_query_wq = NULL;
2061 }
2062}
2063
2064static const struct dmi_system_id acpi_ec_no_wakeup[] = {
2065 {
2066 .ident = "Thinkpad X1 Carbon 6th",
2067 .matches = {
2068 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
2069 DMI_MATCH(DMI_PRODUCT_FAMILY, "Thinkpad X1 Carbon 6th"),
2070 },
2071 },
2072 {
2073 .ident = "ThinkPad X1 Carbon 6th",
2074 .matches = {
2075 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
2076 DMI_MATCH(DMI_PRODUCT_FAMILY, "ThinkPad X1 Carbon 6th"),
2077 },
2078 },
2079 {
2080 .ident = "ThinkPad X1 Yoga 3rd",
2081 .matches = {
2082 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
2083 DMI_MATCH(DMI_PRODUCT_FAMILY, "ThinkPad X1 Yoga 3rd"),
2084 },
2085 },
2086 { },
2087};
2088
2089int __init acpi_ec_init(void)
2090{
2091 int result;
2092 int ecdt_fail, dsdt_fail;
2093
2094 /* register workqueue for _Qxx evaluations */
2095 result = acpi_ec_query_init();
2096 if (result)
2097 return result;
2098
2099 /*
2100 * Disable EC wakeup on following systems to prevent periodic
2101 * wakeup from EC GPE.
2102 */
2103 if (dmi_check_system(acpi_ec_no_wakeup)) {
2104 ec_no_wakeup = true;
2105 pr_debug("Disabling EC wakeup on suspend-to-idle\n");
2106 }
2107
2108 /* Drivers must be started after acpi_ec_query_init() */
2109 dsdt_fail = acpi_bus_register_driver(&acpi_ec_driver);
2110 /*
2111 * Register ECDT to ACPI bus only when PNP0C09 probe fails. This is
2112 * useful for platforms (confirmed on ASUS X550ZE) with valid ECDT
2113 * settings but invalid DSDT settings.
2114 * https://bugzilla.kernel.org/show_bug.cgi?id=196847
2115 */
2116 ecdt_fail = acpi_ec_ecdt_start();
2117 return ecdt_fail && dsdt_fail ? -ENODEV : 0;
2118}
2119
2120/* EC driver currently not unloadable */
2121#if 0
2122static void __exit acpi_ec_exit(void)
2123{
2124
2125 acpi_bus_unregister_driver(&acpi_ec_driver);
2126 acpi_ec_query_exit();
2127}
2128#endif /* 0 */