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Revert "drm/i915: Prevent module unload to avoid random memory corruption"
[deliverable/linux.git] / drivers / acpi / ec.c
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 */
62 enum 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_CDELAY 10 /* Wait 10us before polling EC */
73 #define ACPI_EC_MSI_UDELAY 550 /* Wait 550us for MSI EC */
74
75 #define ACPI_EC_STORM_THRESHOLD 8 /* number of false interrupts
76 per one transaction */
77
78 enum {
79 EC_FLAGS_QUERY_PENDING, /* Query is pending */
80 EC_FLAGS_GPE_STORM, /* GPE storm detected */
81 EC_FLAGS_HANDLERS_INSTALLED, /* Handlers for GPE and
82 * OpReg are installed */
83 EC_FLAGS_BLOCKED, /* Transactions are blocked */
84 };
85
86 /* If we find an EC via the ECDT, we need to keep a ptr to its context */
87 /* External interfaces use first EC only, so remember */
88 typedef int (*acpi_ec_query_func) (void *data);
89
90 struct acpi_ec_query_handler {
91 struct list_head node;
92 acpi_ec_query_func func;
93 acpi_handle handle;
94 void *data;
95 u8 query_bit;
96 };
97
98 struct transaction {
99 const u8 *wdata;
100 u8 *rdata;
101 unsigned short irq_count;
102 u8 command;
103 u8 wi;
104 u8 ri;
105 u8 wlen;
106 u8 rlen;
107 bool done;
108 };
109
110 struct acpi_ec *boot_ec, *first_ec;
111 EXPORT_SYMBOL(first_ec);
112
113 static int EC_FLAGS_MSI; /* Out-of-spec MSI controller */
114 static int EC_FLAGS_VALIDATE_ECDT; /* ASUStec ECDTs need to be validated */
115 static int EC_FLAGS_SKIP_DSDT_SCAN; /* Not all BIOS survive early DSDT scan */
116
117 /* --------------------------------------------------------------------------
118 Transaction Management
119 -------------------------------------------------------------------------- */
120
121 static inline u8 acpi_ec_read_status(struct acpi_ec *ec)
122 {
123 u8 x = inb(ec->command_addr);
124 pr_debug(PREFIX "---> status = 0x%2.2x\n", x);
125 return x;
126 }
127
128 static inline u8 acpi_ec_read_data(struct acpi_ec *ec)
129 {
130 u8 x = inb(ec->data_addr);
131 pr_debug(PREFIX "---> data = 0x%2.2x\n", x);
132 return x;
133 }
134
135 static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command)
136 {
137 pr_debug(PREFIX "<--- command = 0x%2.2x\n", command);
138 outb(command, ec->command_addr);
139 }
140
141 static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data)
142 {
143 pr_debug(PREFIX "<--- data = 0x%2.2x\n", data);
144 outb(data, ec->data_addr);
145 }
146
147 static int ec_transaction_done(struct acpi_ec *ec)
148 {
149 unsigned long flags;
150 int ret = 0;
151 spin_lock_irqsave(&ec->curr_lock, flags);
152 if (!ec->curr || ec->curr->done)
153 ret = 1;
154 spin_unlock_irqrestore(&ec->curr_lock, flags);
155 return ret;
156 }
157
158 static void start_transaction(struct acpi_ec *ec)
159 {
160 ec->curr->irq_count = ec->curr->wi = ec->curr->ri = 0;
161 ec->curr->done = false;
162 acpi_ec_write_cmd(ec, ec->curr->command);
163 }
164
165 static void advance_transaction(struct acpi_ec *ec, u8 status)
166 {
167 unsigned long flags;
168 spin_lock_irqsave(&ec->curr_lock, flags);
169 if (!ec->curr)
170 goto unlock;
171 if (ec->curr->wlen > ec->curr->wi) {
172 if ((status & ACPI_EC_FLAG_IBF) == 0)
173 acpi_ec_write_data(ec,
174 ec->curr->wdata[ec->curr->wi++]);
175 else
176 goto err;
177 } else if (ec->curr->rlen > ec->curr->ri) {
178 if ((status & ACPI_EC_FLAG_OBF) == 1) {
179 ec->curr->rdata[ec->curr->ri++] = acpi_ec_read_data(ec);
180 if (ec->curr->rlen == ec->curr->ri)
181 ec->curr->done = true;
182 } else
183 goto err;
184 } else if (ec->curr->wlen == ec->curr->wi &&
185 (status & ACPI_EC_FLAG_IBF) == 0)
186 ec->curr->done = true;
187 goto unlock;
188 err:
189 /* false interrupt, state didn't change */
190 if (in_interrupt())
191 ++ec->curr->irq_count;
192 unlock:
193 spin_unlock_irqrestore(&ec->curr_lock, flags);
194 }
195
196 static int acpi_ec_sync_query(struct acpi_ec *ec);
197
198 static int ec_check_sci_sync(struct acpi_ec *ec, u8 state)
199 {
200 if (state & ACPI_EC_FLAG_SCI) {
201 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags))
202 return acpi_ec_sync_query(ec);
203 }
204 return 0;
205 }
206
207 static int ec_poll(struct acpi_ec *ec)
208 {
209 unsigned long flags;
210 int repeat = 2; /* number of command restarts */
211 while (repeat--) {
212 unsigned long delay = jiffies +
213 msecs_to_jiffies(ACPI_EC_DELAY);
214 do {
215 /* don't sleep with disabled interrupts */
216 if (EC_FLAGS_MSI || irqs_disabled()) {
217 udelay(ACPI_EC_MSI_UDELAY);
218 if (ec_transaction_done(ec))
219 return 0;
220 } else {
221 if (wait_event_timeout(ec->wait,
222 ec_transaction_done(ec),
223 msecs_to_jiffies(1)))
224 return 0;
225 }
226 advance_transaction(ec, acpi_ec_read_status(ec));
227 } while (time_before(jiffies, delay));
228 if (acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF)
229 break;
230 pr_debug(PREFIX "controller reset, restart transaction\n");
231 spin_lock_irqsave(&ec->curr_lock, flags);
232 start_transaction(ec);
233 spin_unlock_irqrestore(&ec->curr_lock, flags);
234 }
235 return -ETIME;
236 }
237
238 static int acpi_ec_transaction_unlocked(struct acpi_ec *ec,
239 struct transaction *t)
240 {
241 unsigned long tmp;
242 int ret = 0;
243 if (EC_FLAGS_MSI)
244 udelay(ACPI_EC_MSI_UDELAY);
245 /* start transaction */
246 spin_lock_irqsave(&ec->curr_lock, tmp);
247 /* following two actions should be kept atomic */
248 ec->curr = t;
249 start_transaction(ec);
250 if (ec->curr->command == ACPI_EC_COMMAND_QUERY)
251 clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
252 spin_unlock_irqrestore(&ec->curr_lock, tmp);
253 ret = ec_poll(ec);
254 spin_lock_irqsave(&ec->curr_lock, tmp);
255 ec->curr = NULL;
256 spin_unlock_irqrestore(&ec->curr_lock, tmp);
257 return ret;
258 }
259
260 static int ec_check_ibf0(struct acpi_ec *ec)
261 {
262 u8 status = acpi_ec_read_status(ec);
263 return (status & ACPI_EC_FLAG_IBF) == 0;
264 }
265
266 static int ec_wait_ibf0(struct acpi_ec *ec)
267 {
268 unsigned long delay = jiffies + msecs_to_jiffies(ACPI_EC_DELAY);
269 /* interrupt wait manually if GPE mode is not active */
270 while (time_before(jiffies, delay))
271 if (wait_event_timeout(ec->wait, ec_check_ibf0(ec),
272 msecs_to_jiffies(1)))
273 return 0;
274 return -ETIME;
275 }
276
277 static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t)
278 {
279 int status;
280 u32 glk;
281 if (!ec || (!t) || (t->wlen && !t->wdata) || (t->rlen && !t->rdata))
282 return -EINVAL;
283 if (t->rdata)
284 memset(t->rdata, 0, t->rlen);
285 mutex_lock(&ec->lock);
286 if (test_bit(EC_FLAGS_BLOCKED, &ec->flags)) {
287 status = -EINVAL;
288 goto unlock;
289 }
290 if (ec->global_lock) {
291 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
292 if (ACPI_FAILURE(status)) {
293 status = -ENODEV;
294 goto unlock;
295 }
296 }
297 if (ec_wait_ibf0(ec)) {
298 pr_err(PREFIX "input buffer is not empty, "
299 "aborting transaction\n");
300 status = -ETIME;
301 goto end;
302 }
303 pr_debug(PREFIX "transaction start\n");
304 /* disable GPE during transaction if storm is detected */
305 if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
306 /* It has to be disabled, so that it doesn't trigger. */
307 acpi_disable_gpe(NULL, ec->gpe);
308 }
309
310 status = acpi_ec_transaction_unlocked(ec, t);
311
312 /* check if we received SCI during transaction */
313 ec_check_sci_sync(ec, acpi_ec_read_status(ec));
314 if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
315 msleep(1);
316 /* It is safe to enable the GPE outside of the transaction. */
317 acpi_enable_gpe(NULL, ec->gpe);
318 } else if (t->irq_count > ACPI_EC_STORM_THRESHOLD) {
319 pr_info(PREFIX "GPE storm detected, "
320 "transactions will use polling mode\n");
321 set_bit(EC_FLAGS_GPE_STORM, &ec->flags);
322 }
323 pr_debug(PREFIX "transaction end\n");
324 end:
325 if (ec->global_lock)
326 acpi_release_global_lock(glk);
327 unlock:
328 mutex_unlock(&ec->lock);
329 return status;
330 }
331
332 static int acpi_ec_burst_enable(struct acpi_ec *ec)
333 {
334 u8 d;
335 struct transaction t = {.command = ACPI_EC_BURST_ENABLE,
336 .wdata = NULL, .rdata = &d,
337 .wlen = 0, .rlen = 1};
338
339 return acpi_ec_transaction(ec, &t);
340 }
341
342 static int acpi_ec_burst_disable(struct acpi_ec *ec)
343 {
344 struct transaction t = {.command = ACPI_EC_BURST_DISABLE,
345 .wdata = NULL, .rdata = NULL,
346 .wlen = 0, .rlen = 0};
347
348 return (acpi_ec_read_status(ec) & ACPI_EC_FLAG_BURST) ?
349 acpi_ec_transaction(ec, &t) : 0;
350 }
351
352 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 * data)
353 {
354 int result;
355 u8 d;
356 struct transaction t = {.command = ACPI_EC_COMMAND_READ,
357 .wdata = &address, .rdata = &d,
358 .wlen = 1, .rlen = 1};
359
360 result = acpi_ec_transaction(ec, &t);
361 *data = d;
362 return result;
363 }
364
365 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
366 {
367 u8 wdata[2] = { address, data };
368 struct transaction t = {.command = ACPI_EC_COMMAND_WRITE,
369 .wdata = wdata, .rdata = NULL,
370 .wlen = 2, .rlen = 0};
371
372 return acpi_ec_transaction(ec, &t);
373 }
374
375 /*
376 * Externally callable EC access functions. For now, assume 1 EC only
377 */
378 int ec_burst_enable(void)
379 {
380 if (!first_ec)
381 return -ENODEV;
382 return acpi_ec_burst_enable(first_ec);
383 }
384
385 EXPORT_SYMBOL(ec_burst_enable);
386
387 int ec_burst_disable(void)
388 {
389 if (!first_ec)
390 return -ENODEV;
391 return acpi_ec_burst_disable(first_ec);
392 }
393
394 EXPORT_SYMBOL(ec_burst_disable);
395
396 int ec_read(u8 addr, u8 * val)
397 {
398 int err;
399 u8 temp_data;
400
401 if (!first_ec)
402 return -ENODEV;
403
404 err = acpi_ec_read(first_ec, addr, &temp_data);
405
406 if (!err) {
407 *val = temp_data;
408 return 0;
409 } else
410 return err;
411 }
412
413 EXPORT_SYMBOL(ec_read);
414
415 int ec_write(u8 addr, u8 val)
416 {
417 int err;
418
419 if (!first_ec)
420 return -ENODEV;
421
422 err = acpi_ec_write(first_ec, addr, val);
423
424 return err;
425 }
426
427 EXPORT_SYMBOL(ec_write);
428
429 int ec_transaction(u8 command,
430 const u8 * wdata, unsigned wdata_len,
431 u8 * rdata, unsigned rdata_len,
432 int force_poll)
433 {
434 struct transaction t = {.command = command,
435 .wdata = wdata, .rdata = rdata,
436 .wlen = wdata_len, .rlen = rdata_len};
437 if (!first_ec)
438 return -ENODEV;
439
440 return acpi_ec_transaction(first_ec, &t);
441 }
442
443 EXPORT_SYMBOL(ec_transaction);
444
445 void acpi_ec_block_transactions(void)
446 {
447 struct acpi_ec *ec = first_ec;
448
449 if (!ec)
450 return;
451
452 mutex_lock(&ec->lock);
453 /* Prevent transactions from being carried out */
454 set_bit(EC_FLAGS_BLOCKED, &ec->flags);
455 mutex_unlock(&ec->lock);
456 }
457
458 void acpi_ec_unblock_transactions(void)
459 {
460 struct acpi_ec *ec = first_ec;
461
462 if (!ec)
463 return;
464
465 mutex_lock(&ec->lock);
466 /* Allow transactions to be carried out again */
467 clear_bit(EC_FLAGS_BLOCKED, &ec->flags);
468 mutex_unlock(&ec->lock);
469 }
470
471 void acpi_ec_unblock_transactions_early(void)
472 {
473 /*
474 * Allow transactions to happen again (this function is called from
475 * atomic context during wakeup, so we don't need to acquire the mutex).
476 */
477 if (first_ec)
478 clear_bit(EC_FLAGS_BLOCKED, &first_ec->flags);
479 }
480
481 static int acpi_ec_query_unlocked(struct acpi_ec *ec, u8 * data)
482 {
483 int result;
484 u8 d;
485 struct transaction t = {.command = ACPI_EC_COMMAND_QUERY,
486 .wdata = NULL, .rdata = &d,
487 .wlen = 0, .rlen = 1};
488 if (!ec || !data)
489 return -EINVAL;
490 /*
491 * Query the EC to find out which _Qxx method we need to evaluate.
492 * Note that successful completion of the query causes the ACPI_EC_SCI
493 * bit to be cleared (and thus clearing the interrupt source).
494 */
495 result = acpi_ec_transaction_unlocked(ec, &t);
496 if (result)
497 return result;
498 if (!d)
499 return -ENODATA;
500 *data = d;
501 return 0;
502 }
503
504 /* --------------------------------------------------------------------------
505 Event Management
506 -------------------------------------------------------------------------- */
507 int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
508 acpi_handle handle, acpi_ec_query_func func,
509 void *data)
510 {
511 struct acpi_ec_query_handler *handler =
512 kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL);
513 if (!handler)
514 return -ENOMEM;
515
516 handler->query_bit = query_bit;
517 handler->handle = handle;
518 handler->func = func;
519 handler->data = data;
520 mutex_lock(&ec->lock);
521 list_add(&handler->node, &ec->list);
522 mutex_unlock(&ec->lock);
523 return 0;
524 }
525
526 EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler);
527
528 void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit)
529 {
530 struct acpi_ec_query_handler *handler, *tmp;
531 mutex_lock(&ec->lock);
532 list_for_each_entry_safe(handler, tmp, &ec->list, node) {
533 if (query_bit == handler->query_bit) {
534 list_del(&handler->node);
535 kfree(handler);
536 }
537 }
538 mutex_unlock(&ec->lock);
539 }
540
541 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler);
542
543 static void acpi_ec_run(void *cxt)
544 {
545 struct acpi_ec_query_handler *handler = cxt;
546 if (!handler)
547 return;
548 pr_debug(PREFIX "start query execution\n");
549 if (handler->func)
550 handler->func(handler->data);
551 else if (handler->handle)
552 acpi_evaluate_object(handler->handle, NULL, NULL, NULL);
553 pr_debug(PREFIX "stop query execution\n");
554 kfree(handler);
555 }
556
557 static int acpi_ec_sync_query(struct acpi_ec *ec)
558 {
559 u8 value = 0;
560 int status;
561 struct acpi_ec_query_handler *handler, *copy;
562 if ((status = acpi_ec_query_unlocked(ec, &value)))
563 return status;
564 list_for_each_entry(handler, &ec->list, node) {
565 if (value == handler->query_bit) {
566 /* have custom handler for this bit */
567 copy = kmalloc(sizeof(*handler), GFP_KERNEL);
568 if (!copy)
569 return -ENOMEM;
570 memcpy(copy, handler, sizeof(*copy));
571 pr_debug(PREFIX "push query execution (0x%2x) on queue\n", value);
572 return acpi_os_execute((copy->func) ?
573 OSL_NOTIFY_HANDLER : OSL_GPE_HANDLER,
574 acpi_ec_run, copy);
575 }
576 }
577 return 0;
578 }
579
580 static void acpi_ec_gpe_query(void *ec_cxt)
581 {
582 struct acpi_ec *ec = ec_cxt;
583 if (!ec)
584 return;
585 mutex_lock(&ec->lock);
586 acpi_ec_sync_query(ec);
587 mutex_unlock(&ec->lock);
588 }
589
590 static void acpi_ec_gpe_query(void *ec_cxt);
591
592 static int ec_check_sci(struct acpi_ec *ec, u8 state)
593 {
594 if (state & ACPI_EC_FLAG_SCI) {
595 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) {
596 pr_debug(PREFIX "push gpe query to the queue\n");
597 return acpi_os_execute(OSL_NOTIFY_HANDLER,
598 acpi_ec_gpe_query, ec);
599 }
600 }
601 return 0;
602 }
603
604 static u32 acpi_ec_gpe_handler(void *data)
605 {
606 struct acpi_ec *ec = data;
607
608 pr_debug(PREFIX "~~~> interrupt\n");
609
610 advance_transaction(ec, acpi_ec_read_status(ec));
611 if (ec_transaction_done(ec) &&
612 (acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF) == 0) {
613 wake_up(&ec->wait);
614 ec_check_sci(ec, acpi_ec_read_status(ec));
615 }
616 return ACPI_INTERRUPT_HANDLED;
617 }
618
619 /* --------------------------------------------------------------------------
620 Address Space Management
621 -------------------------------------------------------------------------- */
622
623 static acpi_status
624 acpi_ec_space_handler(u32 function, acpi_physical_address address,
625 u32 bits, u64 *value64,
626 void *handler_context, void *region_context)
627 {
628 struct acpi_ec *ec = handler_context;
629 int result = 0, i, bytes = bits / 8;
630 u8 *value = (u8 *)value64;
631
632 if ((address > 0xFF) || !value || !handler_context)
633 return AE_BAD_PARAMETER;
634
635 if (function != ACPI_READ && function != ACPI_WRITE)
636 return AE_BAD_PARAMETER;
637
638 if (EC_FLAGS_MSI || bits > 8)
639 acpi_ec_burst_enable(ec);
640
641 for (i = 0; i < bytes; ++i, ++address, ++value)
642 result = (function == ACPI_READ) ?
643 acpi_ec_read(ec, address, value) :
644 acpi_ec_write(ec, address, *value);
645
646 if (EC_FLAGS_MSI || bits > 8)
647 acpi_ec_burst_disable(ec);
648
649 switch (result) {
650 case -EINVAL:
651 return AE_BAD_PARAMETER;
652 break;
653 case -ENODEV:
654 return AE_NOT_FOUND;
655 break;
656 case -ETIME:
657 return AE_TIME;
658 break;
659 default:
660 return AE_OK;
661 }
662 }
663
664 /* --------------------------------------------------------------------------
665 Driver Interface
666 -------------------------------------------------------------------------- */
667 static acpi_status
668 ec_parse_io_ports(struct acpi_resource *resource, void *context);
669
670 static struct acpi_ec *make_acpi_ec(void)
671 {
672 struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
673 if (!ec)
674 return NULL;
675 ec->flags = 1 << EC_FLAGS_QUERY_PENDING;
676 mutex_init(&ec->lock);
677 init_waitqueue_head(&ec->wait);
678 INIT_LIST_HEAD(&ec->list);
679 spin_lock_init(&ec->curr_lock);
680 return ec;
681 }
682
683 static acpi_status
684 acpi_ec_register_query_methods(acpi_handle handle, u32 level,
685 void *context, void **return_value)
686 {
687 char node_name[5];
688 struct acpi_buffer buffer = { sizeof(node_name), node_name };
689 struct acpi_ec *ec = context;
690 int value = 0;
691 acpi_status status;
692
693 status = acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
694
695 if (ACPI_SUCCESS(status) && sscanf(node_name, "_Q%x", &value) == 1) {
696 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL);
697 }
698 return AE_OK;
699 }
700
701 static acpi_status
702 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
703 {
704 acpi_status status;
705 unsigned long long tmp = 0;
706
707 struct acpi_ec *ec = context;
708
709 /* clear addr values, ec_parse_io_ports depend on it */
710 ec->command_addr = ec->data_addr = 0;
711
712 status = acpi_walk_resources(handle, METHOD_NAME__CRS,
713 ec_parse_io_ports, ec);
714 if (ACPI_FAILURE(status))
715 return status;
716
717 /* Get GPE bit assignment (EC events). */
718 /* TODO: Add support for _GPE returning a package */
719 status = acpi_evaluate_integer(handle, "_GPE", NULL, &tmp);
720 if (ACPI_FAILURE(status))
721 return status;
722 ec->gpe = tmp;
723 /* Use the global lock for all EC transactions? */
724 tmp = 0;
725 acpi_evaluate_integer(handle, "_GLK", NULL, &tmp);
726 ec->global_lock = tmp;
727 ec->handle = handle;
728 return AE_CTRL_TERMINATE;
729 }
730
731 static int ec_install_handlers(struct acpi_ec *ec)
732 {
733 acpi_status status;
734 if (test_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags))
735 return 0;
736 status = acpi_install_gpe_handler(NULL, ec->gpe,
737 ACPI_GPE_EDGE_TRIGGERED,
738 &acpi_ec_gpe_handler, ec);
739 if (ACPI_FAILURE(status))
740 return -ENODEV;
741
742 acpi_enable_gpe(NULL, ec->gpe);
743 status = acpi_install_address_space_handler(ec->handle,
744 ACPI_ADR_SPACE_EC,
745 &acpi_ec_space_handler,
746 NULL, ec);
747 if (ACPI_FAILURE(status)) {
748 if (status == AE_NOT_FOUND) {
749 /*
750 * Maybe OS fails in evaluating the _REG object.
751 * The AE_NOT_FOUND error will be ignored and OS
752 * continue to initialize EC.
753 */
754 printk(KERN_ERR "Fail in evaluating the _REG object"
755 " of EC device. Broken bios is suspected.\n");
756 } else {
757 acpi_remove_gpe_handler(NULL, ec->gpe,
758 &acpi_ec_gpe_handler);
759 acpi_disable_gpe(NULL, ec->gpe);
760 return -ENODEV;
761 }
762 }
763
764 set_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
765 return 0;
766 }
767
768 static void ec_remove_handlers(struct acpi_ec *ec)
769 {
770 acpi_disable_gpe(NULL, ec->gpe);
771 if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle,
772 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler)))
773 pr_err(PREFIX "failed to remove space handler\n");
774 if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe,
775 &acpi_ec_gpe_handler)))
776 pr_err(PREFIX "failed to remove gpe handler\n");
777 clear_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
778 }
779
780 static int acpi_ec_add(struct acpi_device *device)
781 {
782 struct acpi_ec *ec = NULL;
783 int ret;
784
785 strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
786 strcpy(acpi_device_class(device), ACPI_EC_CLASS);
787
788 /* Check for boot EC */
789 if (boot_ec &&
790 (boot_ec->handle == device->handle ||
791 boot_ec->handle == ACPI_ROOT_OBJECT)) {
792 ec = boot_ec;
793 boot_ec = NULL;
794 } else {
795 ec = make_acpi_ec();
796 if (!ec)
797 return -ENOMEM;
798 }
799 if (ec_parse_device(device->handle, 0, ec, NULL) !=
800 AE_CTRL_TERMINATE) {
801 kfree(ec);
802 return -EINVAL;
803 }
804
805 ec->handle = device->handle;
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
830 static 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
855 static acpi_status
856 ec_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
878 int __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
889 static 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 */
895 static 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 */
902 static 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 */
909 static 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
917 static 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_validate_ecdt, "ASUS hardware", {
933 DMI_MATCH(DMI_BIOS_VENDOR, "ASUS") }, NULL},
934 {},
935 };
936
937
938 int __init acpi_ec_ecdt_probe(void)
939 {
940 acpi_status status;
941 struct acpi_ec *saved_ec = NULL;
942 struct acpi_table_ecdt *ecdt_ptr;
943
944 boot_ec = make_acpi_ec();
945 if (!boot_ec)
946 return -ENOMEM;
947 /*
948 * Generate a boot ec context
949 */
950 dmi_check_system(ec_dmi_table);
951 status = acpi_get_table(ACPI_SIG_ECDT, 1,
952 (struct acpi_table_header **)&ecdt_ptr);
953 if (ACPI_SUCCESS(status)) {
954 pr_info(PREFIX "EC description table is found, configuring boot EC\n");
955 boot_ec->command_addr = ecdt_ptr->control.address;
956 boot_ec->data_addr = ecdt_ptr->data.address;
957 boot_ec->gpe = ecdt_ptr->gpe;
958 boot_ec->handle = ACPI_ROOT_OBJECT;
959 acpi_get_handle(ACPI_ROOT_OBJECT, ecdt_ptr->id, &boot_ec->handle);
960 /* Don't trust ECDT, which comes from ASUSTek */
961 if (!EC_FLAGS_VALIDATE_ECDT)
962 goto install;
963 saved_ec = kmemdup(boot_ec, sizeof(struct acpi_ec), GFP_KERNEL);
964 if (!saved_ec)
965 return -ENOMEM;
966 /* fall through */
967 }
968
969 if (EC_FLAGS_SKIP_DSDT_SCAN)
970 return -ENODEV;
971
972 /* This workaround is needed only on some broken machines,
973 * which require early EC, but fail to provide ECDT */
974 printk(KERN_DEBUG PREFIX "Look up EC in DSDT\n");
975 status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device,
976 boot_ec, NULL);
977 /* Check that acpi_get_devices actually find something */
978 if (ACPI_FAILURE(status) || !boot_ec->handle)
979 goto error;
980 if (saved_ec) {
981 /* try to find good ECDT from ASUSTek */
982 if (saved_ec->command_addr != boot_ec->command_addr ||
983 saved_ec->data_addr != boot_ec->data_addr ||
984 saved_ec->gpe != boot_ec->gpe ||
985 saved_ec->handle != boot_ec->handle)
986 pr_info(PREFIX "ASUSTek keeps feeding us with broken "
987 "ECDT tables, which are very hard to workaround. "
988 "Trying to use DSDT EC info instead. Please send "
989 "output of acpidump to linux-acpi@vger.kernel.org\n");
990 kfree(saved_ec);
991 saved_ec = NULL;
992 } else {
993 /* We really need to limit this workaround, the only ASUS,
994 * which needs it, has fake EC._INI method, so use it as flag.
995 * Keep boot_ec struct as it will be needed soon.
996 */
997 acpi_handle dummy;
998 if (!dmi_name_in_vendors("ASUS") ||
999 ACPI_FAILURE(acpi_get_handle(boot_ec->handle, "_INI",
1000 &dummy)))
1001 return -ENODEV;
1002 }
1003 install:
1004 if (!ec_install_handlers(boot_ec)) {
1005 first_ec = boot_ec;
1006 return 0;
1007 }
1008 error:
1009 kfree(boot_ec);
1010 boot_ec = NULL;
1011 return -ENODEV;
1012 }
1013
1014 static struct acpi_driver acpi_ec_driver = {
1015 .name = "ec",
1016 .class = ACPI_EC_CLASS,
1017 .ids = ec_device_ids,
1018 .ops = {
1019 .add = acpi_ec_add,
1020 .remove = acpi_ec_remove,
1021 },
1022 };
1023
1024 int __init acpi_ec_init(void)
1025 {
1026 int result = 0;
1027
1028 /* Now register the driver for the EC */
1029 result = acpi_bus_register_driver(&acpi_ec_driver);
1030 if (result < 0)
1031 return -ENODEV;
1032
1033 return result;
1034 }
1035
1036 /* EC driver currently not unloadable */
1037 #if 0
1038 static void __exit acpi_ec_exit(void)
1039 {
1040
1041 acpi_bus_unregister_driver(&acpi_ec_driver);
1042 return;
1043 }
1044 #endif /* 0 */
Linux kernel - Deliverables
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