sh: hibernation support
[GitHub/mt8127/android_kernel_alcatel_ttab.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/proc_fs.h>
38 #include <linux/seq_file.h>
39 #include <linux/interrupt.h>
40 #include <linux/list.h>
41 #include <linux/spinlock.h>
42 #include <asm/io.h>
43 #include <acpi/acpi_bus.h>
44 #include <acpi/acpi_drivers.h>
45
46 #define ACPI_EC_CLASS "embedded_controller"
47 #define ACPI_EC_DEVICE_NAME "Embedded Controller"
48 #define ACPI_EC_FILE_INFO "info"
49
50 #undef PREFIX
51 #define PREFIX "ACPI: EC: "
52
53 /* EC status register */
54 #define ACPI_EC_FLAG_OBF 0x01 /* Output buffer full */
55 #define ACPI_EC_FLAG_IBF 0x02 /* Input buffer full */
56 #define ACPI_EC_FLAG_BURST 0x10 /* burst mode */
57 #define ACPI_EC_FLAG_SCI 0x20 /* EC-SCI occurred */
58
59 /* EC commands */
60 enum ec_command {
61 ACPI_EC_COMMAND_READ = 0x80,
62 ACPI_EC_COMMAND_WRITE = 0x81,
63 ACPI_EC_BURST_ENABLE = 0x82,
64 ACPI_EC_BURST_DISABLE = 0x83,
65 ACPI_EC_COMMAND_QUERY = 0x84,
66 };
67
68 #define ACPI_EC_DELAY 500 /* Wait 500ms max. during EC ops */
69 #define ACPI_EC_UDELAY_GLK 1000 /* Wait 1ms max. to get global lock */
70 #define ACPI_EC_UDELAY 100 /* Wait 100us before polling EC again */
71
72 #define ACPI_EC_STORM_THRESHOLD 8 /* number of false interrupts
73 per one transaction */
74
75 enum {
76 EC_FLAGS_QUERY_PENDING, /* Query is pending */
77 EC_FLAGS_GPE_MODE, /* Expect GPE to be sent
78 * for status change */
79 EC_FLAGS_NO_GPE, /* Don't use GPE mode */
80 EC_FLAGS_GPE_STORM, /* GPE storm detected */
81 EC_FLAGS_HANDLERS_INSTALLED /* Handlers for GPE and
82 * OpReg are installed */
83 };
84
85 /* If we find an EC via the ECDT, we need to keep a ptr to its context */
86 /* External interfaces use first EC only, so remember */
87 typedef int (*acpi_ec_query_func) (void *data);
88
89 struct acpi_ec_query_handler {
90 struct list_head node;
91 acpi_ec_query_func func;
92 acpi_handle handle;
93 void *data;
94 u8 query_bit;
95 };
96
97 struct transaction {
98 const u8 *wdata;
99 u8 *rdata;
100 unsigned short irq_count;
101 u8 command;
102 u8 wi;
103 u8 ri;
104 u8 wlen;
105 u8 rlen;
106 bool done;
107 };
108
109 static struct acpi_ec {
110 acpi_handle handle;
111 unsigned long gpe;
112 unsigned long command_addr;
113 unsigned long data_addr;
114 unsigned long global_lock;
115 unsigned long flags;
116 struct mutex lock;
117 wait_queue_head_t wait;
118 struct list_head list;
119 struct transaction *curr;
120 spinlock_t curr_lock;
121 } *boot_ec, *first_ec;
122
123 /* --------------------------------------------------------------------------
124 Transaction Management
125 -------------------------------------------------------------------------- */
126
127 static inline u8 acpi_ec_read_status(struct acpi_ec *ec)
128 {
129 u8 x = inb(ec->command_addr);
130 pr_debug(PREFIX "---> status = 0x%2.2x\n", x);
131 return x;
132 }
133
134 static inline u8 acpi_ec_read_data(struct acpi_ec *ec)
135 {
136 u8 x = inb(ec->data_addr);
137 pr_debug(PREFIX "---> data = 0x%2.2x\n", x);
138 return x;
139 }
140
141 static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command)
142 {
143 pr_debug(PREFIX "<--- command = 0x%2.2x\n", command);
144 outb(command, ec->command_addr);
145 }
146
147 static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data)
148 {
149 pr_debug(PREFIX "<--- data = 0x%2.2x\n", data);
150 outb(data, ec->data_addr);
151 }
152
153 static int ec_transaction_done(struct acpi_ec *ec)
154 {
155 unsigned long flags;
156 int ret = 0;
157 spin_lock_irqsave(&ec->curr_lock, flags);
158 if (!ec->curr || ec->curr->done)
159 ret = 1;
160 spin_unlock_irqrestore(&ec->curr_lock, flags);
161 return ret;
162 }
163
164 static void start_transaction(struct acpi_ec *ec)
165 {
166 ec->curr->irq_count = ec->curr->wi = ec->curr->ri = 0;
167 ec->curr->done = false;
168 acpi_ec_write_cmd(ec, ec->curr->command);
169 }
170
171 static void gpe_transaction(struct acpi_ec *ec, u8 status)
172 {
173 unsigned long flags;
174 spin_lock_irqsave(&ec->curr_lock, flags);
175 if (!ec->curr)
176 goto unlock;
177 if (ec->curr->wlen > ec->curr->wi) {
178 if ((status & ACPI_EC_FLAG_IBF) == 0)
179 acpi_ec_write_data(ec,
180 ec->curr->wdata[ec->curr->wi++]);
181 else
182 goto err;
183 } else if (ec->curr->rlen > ec->curr->ri) {
184 if ((status & ACPI_EC_FLAG_OBF) == 1) {
185 ec->curr->rdata[ec->curr->ri++] = acpi_ec_read_data(ec);
186 if (ec->curr->rlen == ec->curr->ri)
187 ec->curr->done = true;
188 } else
189 goto err;
190 } else if (ec->curr->wlen == ec->curr->wi &&
191 (status & ACPI_EC_FLAG_IBF) == 0)
192 ec->curr->done = true;
193 goto unlock;
194 err:
195 /* false interrupt, state didn't change */
196 if (in_interrupt())
197 ++ec->curr->irq_count;
198 unlock:
199 spin_unlock_irqrestore(&ec->curr_lock, flags);
200 }
201
202 static int acpi_ec_wait(struct acpi_ec *ec)
203 {
204 if (wait_event_timeout(ec->wait, ec_transaction_done(ec),
205 msecs_to_jiffies(ACPI_EC_DELAY)))
206 return 0;
207 /* try restart command if we get any false interrupts */
208 if (ec->curr->irq_count &&
209 (acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF) == 0) {
210 pr_debug(PREFIX "controller reset, restart transaction\n");
211 start_transaction(ec);
212 if (wait_event_timeout(ec->wait, ec_transaction_done(ec),
213 msecs_to_jiffies(ACPI_EC_DELAY)))
214 return 0;
215 }
216 /* missing GPEs, switch back to poll mode */
217 if (printk_ratelimit())
218 pr_info(PREFIX "missing confirmations, "
219 "switch off interrupt mode.\n");
220 set_bit(EC_FLAGS_NO_GPE, &ec->flags);
221 clear_bit(EC_FLAGS_GPE_MODE, &ec->flags);
222 return 1;
223 }
224
225 static void acpi_ec_gpe_query(void *ec_cxt);
226
227 static int ec_check_sci(struct acpi_ec *ec, u8 state)
228 {
229 if (state & ACPI_EC_FLAG_SCI) {
230 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags))
231 return acpi_os_execute(OSL_EC_BURST_HANDLER,
232 acpi_ec_gpe_query, ec);
233 }
234 return 0;
235 }
236
237 static int ec_poll(struct acpi_ec *ec)
238 {
239 unsigned long delay = jiffies + msecs_to_jiffies(ACPI_EC_DELAY);
240 udelay(ACPI_EC_UDELAY);
241 while (time_before(jiffies, delay)) {
242 gpe_transaction(ec, acpi_ec_read_status(ec));
243 udelay(ACPI_EC_UDELAY);
244 if (ec_transaction_done(ec))
245 return 0;
246 }
247 return -ETIME;
248 }
249
250 static int acpi_ec_transaction_unlocked(struct acpi_ec *ec,
251 struct transaction *t,
252 int force_poll)
253 {
254 unsigned long tmp;
255 int ret = 0;
256 pr_debug(PREFIX "transaction start\n");
257 /* disable GPE during transaction if storm is detected */
258 if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
259 clear_bit(EC_FLAGS_GPE_MODE, &ec->flags);
260 acpi_disable_gpe(NULL, ec->gpe);
261 }
262 /* start transaction */
263 spin_lock_irqsave(&ec->curr_lock, tmp);
264 /* following two actions should be kept atomic */
265 ec->curr = t;
266 start_transaction(ec);
267 if (ec->curr->command == ACPI_EC_COMMAND_QUERY)
268 clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
269 spin_unlock_irqrestore(&ec->curr_lock, tmp);
270 /* if we selected poll mode or failed in GPE-mode do a poll loop */
271 if (force_poll ||
272 !test_bit(EC_FLAGS_GPE_MODE, &ec->flags) ||
273 acpi_ec_wait(ec))
274 ret = ec_poll(ec);
275 pr_debug(PREFIX "transaction end\n");
276 spin_lock_irqsave(&ec->curr_lock, tmp);
277 ec->curr = NULL;
278 spin_unlock_irqrestore(&ec->curr_lock, tmp);
279 if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
280 /* check if we received SCI during transaction */
281 ec_check_sci(ec, acpi_ec_read_status(ec));
282 /* it is safe to enable GPE outside of transaction */
283 acpi_enable_gpe(NULL, ec->gpe);
284 } else if (test_bit(EC_FLAGS_GPE_MODE, &ec->flags) &&
285 t->irq_count > ACPI_EC_STORM_THRESHOLD) {
286 pr_info(PREFIX "GPE storm detected, "
287 "transactions will use polling mode\n");
288 set_bit(EC_FLAGS_GPE_STORM, &ec->flags);
289 }
290 return ret;
291 }
292
293 static int ec_check_ibf0(struct acpi_ec *ec)
294 {
295 u8 status = acpi_ec_read_status(ec);
296 return (status & ACPI_EC_FLAG_IBF) == 0;
297 }
298
299 static int ec_wait_ibf0(struct acpi_ec *ec)
300 {
301 unsigned long delay = jiffies + msecs_to_jiffies(ACPI_EC_DELAY);
302 /* interrupt wait manually if GPE mode is not active */
303 unsigned long timeout = test_bit(EC_FLAGS_GPE_MODE, &ec->flags) ?
304 msecs_to_jiffies(ACPI_EC_DELAY) : msecs_to_jiffies(1);
305 while (time_before(jiffies, delay))
306 if (wait_event_timeout(ec->wait, ec_check_ibf0(ec), timeout))
307 return 0;
308 return -ETIME;
309 }
310
311 static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t,
312 int force_poll)
313 {
314 int status;
315 u32 glk;
316 if (!ec || (!t) || (t->wlen && !t->wdata) || (t->rlen && !t->rdata))
317 return -EINVAL;
318 if (t->rdata)
319 memset(t->rdata, 0, t->rlen);
320 mutex_lock(&ec->lock);
321 if (ec->global_lock) {
322 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
323 if (ACPI_FAILURE(status)) {
324 status = -ENODEV;
325 goto unlock;
326 }
327 }
328 if (ec_wait_ibf0(ec)) {
329 pr_err(PREFIX "input buffer is not empty, "
330 "aborting transaction\n");
331 status = -ETIME;
332 goto end;
333 }
334 status = acpi_ec_transaction_unlocked(ec, t, force_poll);
335 end:
336 if (ec->global_lock)
337 acpi_release_global_lock(glk);
338 unlock:
339 mutex_unlock(&ec->lock);
340 return status;
341 }
342
343 /*
344 * Note: samsung nv5000 doesn't work with ec burst mode.
345 * http://bugzilla.kernel.org/show_bug.cgi?id=4980
346 */
347 static int acpi_ec_burst_enable(struct acpi_ec *ec)
348 {
349 u8 d;
350 struct transaction t = {.command = ACPI_EC_BURST_ENABLE,
351 .wdata = NULL, .rdata = &d,
352 .wlen = 0, .rlen = 1};
353
354 return acpi_ec_transaction(ec, &t, 0);
355 }
356
357 static int acpi_ec_burst_disable(struct acpi_ec *ec)
358 {
359 struct transaction t = {.command = ACPI_EC_BURST_DISABLE,
360 .wdata = NULL, .rdata = NULL,
361 .wlen = 0, .rlen = 0};
362
363 return (acpi_ec_read_status(ec) & ACPI_EC_FLAG_BURST) ?
364 acpi_ec_transaction(ec, &t, 0) : 0;
365 }
366
367 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 * data)
368 {
369 int result;
370 u8 d;
371 struct transaction t = {.command = ACPI_EC_COMMAND_READ,
372 .wdata = &address, .rdata = &d,
373 .wlen = 1, .rlen = 1};
374
375 result = acpi_ec_transaction(ec, &t, 0);
376 *data = d;
377 return result;
378 }
379
380 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
381 {
382 u8 wdata[2] = { address, data };
383 struct transaction t = {.command = ACPI_EC_COMMAND_WRITE,
384 .wdata = wdata, .rdata = NULL,
385 .wlen = 2, .rlen = 0};
386
387 return acpi_ec_transaction(ec, &t, 0);
388 }
389
390 /*
391 * Externally callable EC access functions. For now, assume 1 EC only
392 */
393 int ec_burst_enable(void)
394 {
395 if (!first_ec)
396 return -ENODEV;
397 return acpi_ec_burst_enable(first_ec);
398 }
399
400 EXPORT_SYMBOL(ec_burst_enable);
401
402 int ec_burst_disable(void)
403 {
404 if (!first_ec)
405 return -ENODEV;
406 return acpi_ec_burst_disable(first_ec);
407 }
408
409 EXPORT_SYMBOL(ec_burst_disable);
410
411 int ec_read(u8 addr, u8 * val)
412 {
413 int err;
414 u8 temp_data;
415
416 if (!first_ec)
417 return -ENODEV;
418
419 err = acpi_ec_read(first_ec, addr, &temp_data);
420
421 if (!err) {
422 *val = temp_data;
423 return 0;
424 } else
425 return err;
426 }
427
428 EXPORT_SYMBOL(ec_read);
429
430 int ec_write(u8 addr, u8 val)
431 {
432 int err;
433
434 if (!first_ec)
435 return -ENODEV;
436
437 err = acpi_ec_write(first_ec, addr, val);
438
439 return err;
440 }
441
442 EXPORT_SYMBOL(ec_write);
443
444 int ec_transaction(u8 command,
445 const u8 * wdata, unsigned wdata_len,
446 u8 * rdata, unsigned rdata_len,
447 int force_poll)
448 {
449 struct transaction t = {.command = command,
450 .wdata = wdata, .rdata = rdata,
451 .wlen = wdata_len, .rlen = rdata_len};
452 if (!first_ec)
453 return -ENODEV;
454
455 return acpi_ec_transaction(first_ec, &t, force_poll);
456 }
457
458 EXPORT_SYMBOL(ec_transaction);
459
460 static int acpi_ec_query(struct acpi_ec *ec, u8 * data)
461 {
462 int result;
463 u8 d;
464 struct transaction t = {.command = ACPI_EC_COMMAND_QUERY,
465 .wdata = NULL, .rdata = &d,
466 .wlen = 0, .rlen = 1};
467 if (!ec || !data)
468 return -EINVAL;
469
470 /*
471 * Query the EC to find out which _Qxx method we need to evaluate.
472 * Note that successful completion of the query causes the ACPI_EC_SCI
473 * bit to be cleared (and thus clearing the interrupt source).
474 */
475
476 result = acpi_ec_transaction(ec, &t, 0);
477 if (result)
478 return result;
479
480 if (!d)
481 return -ENODATA;
482
483 *data = d;
484 return 0;
485 }
486
487 /* --------------------------------------------------------------------------
488 Event Management
489 -------------------------------------------------------------------------- */
490 int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
491 acpi_handle handle, acpi_ec_query_func func,
492 void *data)
493 {
494 struct acpi_ec_query_handler *handler =
495 kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL);
496 if (!handler)
497 return -ENOMEM;
498
499 handler->query_bit = query_bit;
500 handler->handle = handle;
501 handler->func = func;
502 handler->data = data;
503 mutex_lock(&ec->lock);
504 list_add(&handler->node, &ec->list);
505 mutex_unlock(&ec->lock);
506 return 0;
507 }
508
509 EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler);
510
511 void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit)
512 {
513 struct acpi_ec_query_handler *handler, *tmp;
514 mutex_lock(&ec->lock);
515 list_for_each_entry_safe(handler, tmp, &ec->list, node) {
516 if (query_bit == handler->query_bit) {
517 list_del(&handler->node);
518 kfree(handler);
519 }
520 }
521 mutex_unlock(&ec->lock);
522 }
523
524 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler);
525
526 static void acpi_ec_gpe_query(void *ec_cxt)
527 {
528 struct acpi_ec *ec = ec_cxt;
529 u8 value = 0;
530 struct acpi_ec_query_handler *handler, copy;
531
532 if (!ec || acpi_ec_query(ec, &value))
533 return;
534 mutex_lock(&ec->lock);
535 list_for_each_entry(handler, &ec->list, node) {
536 if (value == handler->query_bit) {
537 /* have custom handler for this bit */
538 memcpy(&copy, handler, sizeof(copy));
539 mutex_unlock(&ec->lock);
540 if (copy.func) {
541 copy.func(copy.data);
542 } else if (copy.handle) {
543 acpi_evaluate_object(copy.handle, NULL, NULL, NULL);
544 }
545 return;
546 }
547 }
548 mutex_unlock(&ec->lock);
549 }
550
551 static u32 acpi_ec_gpe_handler(void *data)
552 {
553 struct acpi_ec *ec = data;
554 u8 status;
555
556 pr_debug(PREFIX "~~~> interrupt\n");
557 status = acpi_ec_read_status(ec);
558
559 if (test_bit(EC_FLAGS_GPE_MODE, &ec->flags)) {
560 gpe_transaction(ec, status);
561 if (ec_transaction_done(ec) &&
562 (status & ACPI_EC_FLAG_IBF) == 0)
563 wake_up(&ec->wait);
564 }
565
566 ec_check_sci(ec, status);
567 if (!test_bit(EC_FLAGS_GPE_MODE, &ec->flags) &&
568 !test_bit(EC_FLAGS_NO_GPE, &ec->flags)) {
569 /* this is non-query, must be confirmation */
570 if (!test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
571 if (printk_ratelimit())
572 pr_info(PREFIX "non-query interrupt received,"
573 " switching to interrupt mode\n");
574 } else {
575 /* hush, STORM switches the mode every transaction */
576 pr_debug(PREFIX "non-query interrupt received,"
577 " switching to interrupt mode\n");
578 }
579 set_bit(EC_FLAGS_GPE_MODE, &ec->flags);
580 }
581 return ACPI_INTERRUPT_HANDLED;
582 }
583
584 /* --------------------------------------------------------------------------
585 Address Space Management
586 -------------------------------------------------------------------------- */
587
588 static acpi_status
589 acpi_ec_space_handler(u32 function, acpi_physical_address address,
590 u32 bits, acpi_integer *value,
591 void *handler_context, void *region_context)
592 {
593 struct acpi_ec *ec = handler_context;
594 int result = 0, i;
595 u8 temp = 0;
596
597 if ((address > 0xFF) || !value || !handler_context)
598 return AE_BAD_PARAMETER;
599
600 if (function != ACPI_READ && function != ACPI_WRITE)
601 return AE_BAD_PARAMETER;
602
603 if (bits != 8 && acpi_strict)
604 return AE_BAD_PARAMETER;
605
606 acpi_ec_burst_enable(ec);
607
608 if (function == ACPI_READ) {
609 result = acpi_ec_read(ec, address, &temp);
610 *value = temp;
611 } else {
612 temp = 0xff & (*value);
613 result = acpi_ec_write(ec, address, temp);
614 }
615
616 for (i = 8; unlikely(bits - i > 0); i += 8) {
617 ++address;
618 if (function == ACPI_READ) {
619 result = acpi_ec_read(ec, address, &temp);
620 (*value) |= ((acpi_integer)temp) << i;
621 } else {
622 temp = 0xff & ((*value) >> i);
623 result = acpi_ec_write(ec, address, temp);
624 }
625 }
626
627 acpi_ec_burst_disable(ec);
628
629 switch (result) {
630 case -EINVAL:
631 return AE_BAD_PARAMETER;
632 break;
633 case -ENODEV:
634 return AE_NOT_FOUND;
635 break;
636 case -ETIME:
637 return AE_TIME;
638 break;
639 default:
640 return AE_OK;
641 }
642 }
643
644 /* --------------------------------------------------------------------------
645 FS Interface (/proc)
646 -------------------------------------------------------------------------- */
647
648 static struct proc_dir_entry *acpi_ec_dir;
649
650 static int acpi_ec_read_info(struct seq_file *seq, void *offset)
651 {
652 struct acpi_ec *ec = seq->private;
653
654 if (!ec)
655 goto end;
656
657 seq_printf(seq, "gpe:\t\t\t0x%02x\n", (u32) ec->gpe);
658 seq_printf(seq, "ports:\t\t\t0x%02x, 0x%02x\n",
659 (unsigned)ec->command_addr, (unsigned)ec->data_addr);
660 seq_printf(seq, "use global lock:\t%s\n",
661 ec->global_lock ? "yes" : "no");
662 end:
663 return 0;
664 }
665
666 static int acpi_ec_info_open_fs(struct inode *inode, struct file *file)
667 {
668 return single_open(file, acpi_ec_read_info, PDE(inode)->data);
669 }
670
671 static struct file_operations acpi_ec_info_ops = {
672 .open = acpi_ec_info_open_fs,
673 .read = seq_read,
674 .llseek = seq_lseek,
675 .release = single_release,
676 .owner = THIS_MODULE,
677 };
678
679 static int acpi_ec_add_fs(struct acpi_device *device)
680 {
681 struct proc_dir_entry *entry = NULL;
682
683 if (!acpi_device_dir(device)) {
684 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
685 acpi_ec_dir);
686 if (!acpi_device_dir(device))
687 return -ENODEV;
688 }
689
690 entry = proc_create_data(ACPI_EC_FILE_INFO, S_IRUGO,
691 acpi_device_dir(device),
692 &acpi_ec_info_ops, acpi_driver_data(device));
693 if (!entry)
694 return -ENODEV;
695 return 0;
696 }
697
698 static int acpi_ec_remove_fs(struct acpi_device *device)
699 {
700
701 if (acpi_device_dir(device)) {
702 remove_proc_entry(ACPI_EC_FILE_INFO, acpi_device_dir(device));
703 remove_proc_entry(acpi_device_bid(device), acpi_ec_dir);
704 acpi_device_dir(device) = NULL;
705 }
706
707 return 0;
708 }
709
710 /* --------------------------------------------------------------------------
711 Driver Interface
712 -------------------------------------------------------------------------- */
713 static acpi_status
714 ec_parse_io_ports(struct acpi_resource *resource, void *context);
715
716 static struct acpi_ec *make_acpi_ec(void)
717 {
718 struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
719 if (!ec)
720 return NULL;
721 ec->flags = 1 << EC_FLAGS_QUERY_PENDING;
722 mutex_init(&ec->lock);
723 init_waitqueue_head(&ec->wait);
724 INIT_LIST_HEAD(&ec->list);
725 spin_lock_init(&ec->curr_lock);
726 return ec;
727 }
728
729 static acpi_status
730 acpi_ec_register_query_methods(acpi_handle handle, u32 level,
731 void *context, void **return_value)
732 {
733 char node_name[5];
734 struct acpi_buffer buffer = { sizeof(node_name), node_name };
735 struct acpi_ec *ec = context;
736 int value = 0;
737 acpi_status status;
738
739 status = acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
740
741 if (ACPI_SUCCESS(status) && sscanf(node_name, "_Q%x", &value) == 1) {
742 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL);
743 }
744 return AE_OK;
745 }
746
747 static acpi_status
748 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
749 {
750 acpi_status status;
751 unsigned long long tmp = 0;
752
753 struct acpi_ec *ec = context;
754 status = acpi_walk_resources(handle, METHOD_NAME__CRS,
755 ec_parse_io_ports, ec);
756 if (ACPI_FAILURE(status))
757 return status;
758
759 /* Get GPE bit assignment (EC events). */
760 /* TODO: Add support for _GPE returning a package */
761 status = acpi_evaluate_integer(handle, "_GPE", NULL, &tmp);
762 if (ACPI_FAILURE(status))
763 return status;
764 ec->gpe = tmp;
765 /* Use the global lock for all EC transactions? */
766 tmp = 0;
767 acpi_evaluate_integer(handle, "_GLK", NULL, &tmp);
768 ec->global_lock = tmp;
769 ec->handle = handle;
770 return AE_CTRL_TERMINATE;
771 }
772
773 static void ec_remove_handlers(struct acpi_ec *ec)
774 {
775 if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle,
776 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler)))
777 pr_err(PREFIX "failed to remove space handler\n");
778 if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe,
779 &acpi_ec_gpe_handler)))
780 pr_err(PREFIX "failed to remove gpe handler\n");
781 clear_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
782 }
783
784 static int acpi_ec_add(struct acpi_device *device)
785 {
786 struct acpi_ec *ec = NULL;
787
788 if (!device)
789 return -EINVAL;
790 strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
791 strcpy(acpi_device_class(device), ACPI_EC_CLASS);
792
793 /* Check for boot EC */
794 if (boot_ec &&
795 (boot_ec->handle == device->handle ||
796 boot_ec->handle == ACPI_ROOT_OBJECT)) {
797 ec = boot_ec;
798 boot_ec = NULL;
799 } else {
800 ec = make_acpi_ec();
801 if (!ec)
802 return -ENOMEM;
803 if (ec_parse_device(device->handle, 0, ec, NULL) !=
804 AE_CTRL_TERMINATE) {
805 kfree(ec);
806 return -EINVAL;
807 }
808 }
809
810 ec->handle = device->handle;
811
812 /* Find and register all query methods */
813 acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1,
814 acpi_ec_register_query_methods, ec, NULL);
815
816 if (!first_ec)
817 first_ec = ec;
818 device->driver_data = ec;
819 acpi_ec_add_fs(device);
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 pr_info(PREFIX "driver started in %s mode\n",
823 (test_bit(EC_FLAGS_GPE_MODE, &ec->flags))?"interrupt":"poll");
824 return 0;
825 }
826
827 static int acpi_ec_remove(struct acpi_device *device, int type)
828 {
829 struct acpi_ec *ec;
830 struct acpi_ec_query_handler *handler, *tmp;
831
832 if (!device)
833 return -EINVAL;
834
835 ec = acpi_driver_data(device);
836 mutex_lock(&ec->lock);
837 list_for_each_entry_safe(handler, tmp, &ec->list, node) {
838 list_del(&handler->node);
839 kfree(handler);
840 }
841 mutex_unlock(&ec->lock);
842 acpi_ec_remove_fs(device);
843 device->driver_data = NULL;
844 if (ec == first_ec)
845 first_ec = NULL;
846 kfree(ec);
847 return 0;
848 }
849
850 static acpi_status
851 ec_parse_io_ports(struct acpi_resource *resource, void *context)
852 {
853 struct acpi_ec *ec = context;
854
855 if (resource->type != ACPI_RESOURCE_TYPE_IO)
856 return AE_OK;
857
858 /*
859 * The first address region returned is the data port, and
860 * the second address region returned is the status/command
861 * port.
862 */
863 if (ec->data_addr == 0)
864 ec->data_addr = resource->data.io.minimum;
865 else if (ec->command_addr == 0)
866 ec->command_addr = resource->data.io.minimum;
867 else
868 return AE_CTRL_TERMINATE;
869
870 return AE_OK;
871 }
872
873 static int ec_install_handlers(struct acpi_ec *ec)
874 {
875 acpi_status status;
876 if (test_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags))
877 return 0;
878 status = acpi_install_gpe_handler(NULL, ec->gpe,
879 ACPI_GPE_EDGE_TRIGGERED,
880 &acpi_ec_gpe_handler, ec);
881 if (ACPI_FAILURE(status))
882 return -ENODEV;
883 acpi_set_gpe_type(NULL, ec->gpe, ACPI_GPE_TYPE_RUNTIME);
884 acpi_enable_gpe(NULL, ec->gpe);
885 status = acpi_install_address_space_handler(ec->handle,
886 ACPI_ADR_SPACE_EC,
887 &acpi_ec_space_handler,
888 NULL, ec);
889 if (ACPI_FAILURE(status)) {
890 if (status == AE_NOT_FOUND) {
891 /*
892 * Maybe OS fails in evaluating the _REG object.
893 * The AE_NOT_FOUND error will be ignored and OS
894 * continue to initialize EC.
895 */
896 printk(KERN_ERR "Fail in evaluating the _REG object"
897 " of EC device. Broken bios is suspected.\n");
898 } else {
899 acpi_remove_gpe_handler(NULL, ec->gpe,
900 &acpi_ec_gpe_handler);
901 return -ENODEV;
902 }
903 }
904
905 set_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
906 return 0;
907 }
908
909 static int acpi_ec_start(struct acpi_device *device)
910 {
911 struct acpi_ec *ec;
912 int ret = 0;
913
914 if (!device)
915 return -EINVAL;
916
917 ec = acpi_driver_data(device);
918
919 if (!ec)
920 return -EINVAL;
921
922 ret = ec_install_handlers(ec);
923
924 /* EC is fully operational, allow queries */
925 clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
926 return ret;
927 }
928
929 static int acpi_ec_stop(struct acpi_device *device, int type)
930 {
931 struct acpi_ec *ec;
932 if (!device)
933 return -EINVAL;
934 ec = acpi_driver_data(device);
935 if (!ec)
936 return -EINVAL;
937 ec_remove_handlers(ec);
938
939 return 0;
940 }
941
942 int __init acpi_boot_ec_enable(void)
943 {
944 if (!boot_ec || test_bit(EC_FLAGS_HANDLERS_INSTALLED, &boot_ec->flags))
945 return 0;
946 if (!ec_install_handlers(boot_ec)) {
947 first_ec = boot_ec;
948 return 0;
949 }
950 return -EFAULT;
951 }
952
953 static const struct acpi_device_id ec_device_ids[] = {
954 {"PNP0C09", 0},
955 {"", 0},
956 };
957
958 int __init acpi_ec_ecdt_probe(void)
959 {
960 acpi_status status;
961 struct acpi_ec *saved_ec = NULL;
962 struct acpi_table_ecdt *ecdt_ptr;
963
964 boot_ec = make_acpi_ec();
965 if (!boot_ec)
966 return -ENOMEM;
967 /*
968 * Generate a boot ec context
969 */
970 status = acpi_get_table(ACPI_SIG_ECDT, 1,
971 (struct acpi_table_header **)&ecdt_ptr);
972 if (ACPI_SUCCESS(status)) {
973 pr_info(PREFIX "EC description table is found, configuring boot EC\n");
974 boot_ec->command_addr = ecdt_ptr->control.address;
975 boot_ec->data_addr = ecdt_ptr->data.address;
976 boot_ec->gpe = ecdt_ptr->gpe;
977 boot_ec->handle = ACPI_ROOT_OBJECT;
978 acpi_get_handle(ACPI_ROOT_OBJECT, ecdt_ptr->id, &boot_ec->handle);
979 /* Don't trust ECDT, which comes from ASUSTek */
980 if (!dmi_name_in_vendors("ASUS"))
981 goto install;
982 saved_ec = kmalloc(sizeof(struct acpi_ec), GFP_KERNEL);
983 if (!saved_ec)
984 return -ENOMEM;
985 memcpy(saved_ec, boot_ec, sizeof(*saved_ec));
986 /* fall through */
987 }
988 /* This workaround is needed only on some broken machines,
989 * which require early EC, but fail to provide ECDT */
990 printk(KERN_DEBUG PREFIX "Look up EC in DSDT\n");
991 status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device,
992 boot_ec, NULL);
993 /* Check that acpi_get_devices actually find something */
994 if (ACPI_FAILURE(status) || !boot_ec->handle)
995 goto error;
996 if (saved_ec) {
997 /* try to find good ECDT from ASUSTek */
998 if (saved_ec->command_addr != boot_ec->command_addr ||
999 saved_ec->data_addr != boot_ec->data_addr ||
1000 saved_ec->gpe != boot_ec->gpe ||
1001 saved_ec->handle != boot_ec->handle)
1002 pr_info(PREFIX "ASUSTek keeps feeding us with broken "
1003 "ECDT tables, which are very hard to workaround. "
1004 "Trying to use DSDT EC info instead. Please send "
1005 "output of acpidump to linux-acpi@vger.kernel.org\n");
1006 kfree(saved_ec);
1007 saved_ec = NULL;
1008 } else {
1009 /* We really need to limit this workaround, the only ASUS,
1010 * which needs it, has fake EC._INI method, so use it as flag.
1011 * Keep boot_ec struct as it will be needed soon.
1012 */
1013 acpi_handle dummy;
1014 if (!dmi_name_in_vendors("ASUS") ||
1015 ACPI_FAILURE(acpi_get_handle(boot_ec->handle, "_INI",
1016 &dummy)))
1017 return -ENODEV;
1018 }
1019 install:
1020 if (!ec_install_handlers(boot_ec)) {
1021 first_ec = boot_ec;
1022 return 0;
1023 }
1024 error:
1025 kfree(boot_ec);
1026 boot_ec = NULL;
1027 return -ENODEV;
1028 }
1029
1030 static int acpi_ec_suspend(struct acpi_device *device, pm_message_t state)
1031 {
1032 struct acpi_ec *ec = acpi_driver_data(device);
1033 /* Stop using GPE */
1034 set_bit(EC_FLAGS_NO_GPE, &ec->flags);
1035 clear_bit(EC_FLAGS_GPE_MODE, &ec->flags);
1036 acpi_disable_gpe(NULL, ec->gpe);
1037 return 0;
1038 }
1039
1040 static int acpi_ec_resume(struct acpi_device *device)
1041 {
1042 struct acpi_ec *ec = acpi_driver_data(device);
1043 /* Enable use of GPE back */
1044 clear_bit(EC_FLAGS_NO_GPE, &ec->flags);
1045 acpi_enable_gpe(NULL, ec->gpe);
1046 return 0;
1047 }
1048
1049 static struct acpi_driver acpi_ec_driver = {
1050 .name = "ec",
1051 .class = ACPI_EC_CLASS,
1052 .ids = ec_device_ids,
1053 .ops = {
1054 .add = acpi_ec_add,
1055 .remove = acpi_ec_remove,
1056 .start = acpi_ec_start,
1057 .stop = acpi_ec_stop,
1058 .suspend = acpi_ec_suspend,
1059 .resume = acpi_ec_resume,
1060 },
1061 };
1062
1063 static int __init acpi_ec_init(void)
1064 {
1065 int result = 0;
1066
1067 if (acpi_disabled)
1068 return 0;
1069
1070 acpi_ec_dir = proc_mkdir(ACPI_EC_CLASS, acpi_root_dir);
1071 if (!acpi_ec_dir)
1072 return -ENODEV;
1073
1074 /* Now register the driver for the EC */
1075 result = acpi_bus_register_driver(&acpi_ec_driver);
1076 if (result < 0) {
1077 remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1078 return -ENODEV;
1079 }
1080
1081 return result;
1082 }
1083
1084 subsys_initcall(acpi_ec_init);
1085
1086 /* EC driver currently not unloadable */
1087 #if 0
1088 static void __exit acpi_ec_exit(void)
1089 {
1090
1091 acpi_bus_unregister_driver(&acpi_ec_driver);
1092
1093 remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1094
1095 return;
1096 }
1097 #endif /* 0 */