ACPI: EC: Accelerate query execution
[linux-2.6.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 #include <linux/dmi.h>
46
47 #define ACPI_EC_CLASS                   "embedded_controller"
48 #define ACPI_EC_DEVICE_NAME             "Embedded Controller"
49 #define ACPI_EC_FILE_INFO               "info"
50
51 #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_CDELAY          10      /* Wait 10us before polling EC */
71 #define ACPI_EC_MSI_UDELAY      550     /* Wait 550us for MSI EC */
72
73 #define ACPI_EC_STORM_THRESHOLD 8       /* number of false interrupts
74                                            per one transaction */
75
76 enum {
77         EC_FLAGS_QUERY_PENDING,         /* Query is pending */
78         EC_FLAGS_GPE_STORM,             /* GPE storm detected */
79         EC_FLAGS_HANDLERS_INSTALLED     /* Handlers for GPE and
80                                          * OpReg are installed */
81 };
82
83 /* If we find an EC via the ECDT, we need to keep a ptr to its context */
84 /* External interfaces use first EC only, so remember */
85 typedef int (*acpi_ec_query_func) (void *data);
86
87 struct acpi_ec_query_handler {
88         struct list_head node;
89         acpi_ec_query_func func;
90         acpi_handle handle;
91         void *data;
92         u8 query_bit;
93 };
94
95 struct transaction {
96         const u8 *wdata;
97         u8 *rdata;
98         unsigned short irq_count;
99         u8 command;
100         u8 wi;
101         u8 ri;
102         u8 wlen;
103         u8 rlen;
104         bool done;
105 };
106
107 static struct acpi_ec {
108         acpi_handle handle;
109         unsigned long gpe;
110         unsigned long command_addr;
111         unsigned long data_addr;
112         unsigned long global_lock;
113         unsigned long flags;
114         struct mutex lock;
115         wait_queue_head_t wait;
116         struct list_head list;
117         struct transaction *curr;
118         spinlock_t curr_lock;
119 } *boot_ec, *first_ec;
120
121 static int EC_FLAGS_MSI; /* Out-of-spec MSI controller */
122 static int EC_FLAGS_VALIDATE_ECDT; /* ASUStec ECDTs need to be validated */
123 static int EC_FLAGS_SKIP_DSDT_SCAN; /* Not all BIOS survive early DSDT scan */
124
125 /* --------------------------------------------------------------------------
126                              Transaction Management
127    -------------------------------------------------------------------------- */
128
129 static inline u8 acpi_ec_read_status(struct acpi_ec *ec)
130 {
131         u8 x = inb(ec->command_addr);
132         pr_debug(PREFIX "---> status = 0x%2.2x\n", x);
133         return x;
134 }
135
136 static inline u8 acpi_ec_read_data(struct acpi_ec *ec)
137 {
138         u8 x = inb(ec->data_addr);
139         pr_debug(PREFIX "---> data = 0x%2.2x\n", x);
140         return x;
141 }
142
143 static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command)
144 {
145         pr_debug(PREFIX "<--- command = 0x%2.2x\n", command);
146         outb(command, ec->command_addr);
147 }
148
149 static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data)
150 {
151         pr_debug(PREFIX "<--- data = 0x%2.2x\n", data);
152         outb(data, ec->data_addr);
153 }
154
155 static int ec_transaction_done(struct acpi_ec *ec)
156 {
157         unsigned long flags;
158         int ret = 0;
159         spin_lock_irqsave(&ec->curr_lock, flags);
160         if (!ec->curr || ec->curr->done)
161                 ret = 1;
162         spin_unlock_irqrestore(&ec->curr_lock, flags);
163         return ret;
164 }
165
166 static void start_transaction(struct acpi_ec *ec)
167 {
168         ec->curr->irq_count = ec->curr->wi = ec->curr->ri = 0;
169         ec->curr->done = false;
170         acpi_ec_write_cmd(ec, ec->curr->command);
171 }
172
173 static void advance_transaction(struct acpi_ec *ec, u8 status)
174 {
175         unsigned long flags;
176         spin_lock_irqsave(&ec->curr_lock, flags);
177         if (!ec->curr)
178                 goto unlock;
179         if (ec->curr->wlen > ec->curr->wi) {
180                 if ((status & ACPI_EC_FLAG_IBF) == 0)
181                         acpi_ec_write_data(ec,
182                                 ec->curr->wdata[ec->curr->wi++]);
183                 else
184                         goto err;
185         } else if (ec->curr->rlen > ec->curr->ri) {
186                 if ((status & ACPI_EC_FLAG_OBF) == 1) {
187                         ec->curr->rdata[ec->curr->ri++] = acpi_ec_read_data(ec);
188                         if (ec->curr->rlen == ec->curr->ri)
189                                 ec->curr->done = true;
190                 } else
191                         goto err;
192         } else if (ec->curr->wlen == ec->curr->wi &&
193                    (status & ACPI_EC_FLAG_IBF) == 0)
194                 ec->curr->done = true;
195         goto unlock;
196 err:
197         /* false interrupt, state didn't change */
198         if (in_interrupt())
199                 ++ec->curr->irq_count;
200 unlock:
201         spin_unlock_irqrestore(&ec->curr_lock, flags);
202 }
203
204 static int acpi_ec_sync_query(struct acpi_ec *ec);
205
206 static int ec_check_sci_sync(struct acpi_ec *ec, u8 state)
207 {
208         if (state & ACPI_EC_FLAG_SCI) {
209                 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags))
210                         return acpi_ec_sync_query(ec);
211         }
212         return 0;
213 }
214
215 static int ec_poll(struct acpi_ec *ec)
216 {
217         unsigned long flags;
218         int repeat = 2; /* number of command restarts */
219         while (repeat--) {
220                 unsigned long delay = jiffies +
221                         msecs_to_jiffies(ACPI_EC_DELAY);
222                 do {
223                         /* don't sleep with disabled interrupts */
224                         if (EC_FLAGS_MSI || irqs_disabled()) {
225                                 udelay(ACPI_EC_MSI_UDELAY);
226                                 if (ec_transaction_done(ec))
227                                         return 0;
228                         } else {
229                                 if (wait_event_timeout(ec->wait,
230                                                 ec_transaction_done(ec),
231                                                 msecs_to_jiffies(1)))
232                                         return 0;
233                         }
234                         advance_transaction(ec, acpi_ec_read_status(ec));
235                 } while (time_before(jiffies, delay));
236                 if (acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF)
237                         break;
238                 pr_debug(PREFIX "controller reset, restart transaction\n");
239                 spin_lock_irqsave(&ec->curr_lock, flags);
240                 start_transaction(ec);
241                 spin_unlock_irqrestore(&ec->curr_lock, flags);
242         }
243         return -ETIME;
244 }
245
246 static int acpi_ec_transaction_unlocked(struct acpi_ec *ec,
247                                         struct transaction *t)
248 {
249         unsigned long tmp;
250         int ret = 0;
251         if (EC_FLAGS_MSI)
252                 udelay(ACPI_EC_MSI_UDELAY);
253         /* start transaction */
254         spin_lock_irqsave(&ec->curr_lock, tmp);
255         /* following two actions should be kept atomic */
256         ec->curr = t;
257         start_transaction(ec);
258         if (ec->curr->command == ACPI_EC_COMMAND_QUERY)
259                 clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
260         spin_unlock_irqrestore(&ec->curr_lock, tmp);
261         ret = ec_poll(ec);
262         pr_debug(PREFIX "transaction end\n");
263         spin_lock_irqsave(&ec->curr_lock, tmp);
264         ec->curr = NULL;
265         spin_unlock_irqrestore(&ec->curr_lock, tmp);
266         return ret;
267 }
268
269 static int ec_check_ibf0(struct acpi_ec *ec)
270 {
271         u8 status = acpi_ec_read_status(ec);
272         return (status & ACPI_EC_FLAG_IBF) == 0;
273 }
274
275 static int ec_wait_ibf0(struct acpi_ec *ec)
276 {
277         unsigned long delay = jiffies + msecs_to_jiffies(ACPI_EC_DELAY);
278         /* interrupt wait manually if GPE mode is not active */
279         while (time_before(jiffies, delay))
280                 if (wait_event_timeout(ec->wait, ec_check_ibf0(ec),
281                                         msecs_to_jiffies(1)))
282                         return 0;
283         return -ETIME;
284 }
285
286 static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t)
287 {
288         int status;
289         u32 glk;
290         if (!ec || (!t) || (t->wlen && !t->wdata) || (t->rlen && !t->rdata))
291                 return -EINVAL;
292         if (t->rdata)
293                 memset(t->rdata, 0, t->rlen);
294         mutex_lock(&ec->lock);
295         if (ec->global_lock) {
296                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
297                 if (ACPI_FAILURE(status)) {
298                         status = -ENODEV;
299                         goto unlock;
300                 }
301         }
302         if (ec_wait_ibf0(ec)) {
303                 pr_err(PREFIX "input buffer is not empty, "
304                                 "aborting transaction\n");
305                 status = -ETIME;
306                 goto end;
307         }
308         pr_debug(PREFIX "transaction start\n");
309         /* disable GPE during transaction if storm is detected */
310         if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
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                 /* it is safe to enable GPE outside of transaction */
320                 acpi_enable_gpe(NULL, ec->gpe);
321         } else if (t->irq_count > ACPI_EC_STORM_THRESHOLD) {
322                 pr_info(PREFIX "GPE storm detected, "
323                         "transactions will use polling mode\n");
324                 set_bit(EC_FLAGS_GPE_STORM, &ec->flags);
325         }
326 end:
327         if (ec->global_lock)
328                 acpi_release_global_lock(glk);
329 unlock:
330         mutex_unlock(&ec->lock);
331         return status;
332 }
333
334 static int acpi_ec_burst_enable(struct acpi_ec *ec)
335 {
336         u8 d;
337         struct transaction t = {.command = ACPI_EC_BURST_ENABLE,
338                                 .wdata = NULL, .rdata = &d,
339                                 .wlen = 0, .rlen = 1};
340
341         return acpi_ec_transaction(ec, &t);
342 }
343
344 static int acpi_ec_burst_disable(struct acpi_ec *ec)
345 {
346         struct transaction t = {.command = ACPI_EC_BURST_DISABLE,
347                                 .wdata = NULL, .rdata = NULL,
348                                 .wlen = 0, .rlen = 0};
349
350         return (acpi_ec_read_status(ec) & ACPI_EC_FLAG_BURST) ?
351                                 acpi_ec_transaction(ec, &t) : 0;
352 }
353
354 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 * data)
355 {
356         int result;
357         u8 d;
358         struct transaction t = {.command = ACPI_EC_COMMAND_READ,
359                                 .wdata = &address, .rdata = &d,
360                                 .wlen = 1, .rlen = 1};
361
362         result = acpi_ec_transaction(ec, &t);
363         *data = d;
364         return result;
365 }
366
367 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
368 {
369         u8 wdata[2] = { address, data };
370         struct transaction t = {.command = ACPI_EC_COMMAND_WRITE,
371                                 .wdata = wdata, .rdata = NULL,
372                                 .wlen = 2, .rlen = 0};
373
374         return acpi_ec_transaction(ec, &t);
375 }
376
377 /*
378  * Externally callable EC access functions. For now, assume 1 EC only
379  */
380 int ec_burst_enable(void)
381 {
382         if (!first_ec)
383                 return -ENODEV;
384         return acpi_ec_burst_enable(first_ec);
385 }
386
387 EXPORT_SYMBOL(ec_burst_enable);
388
389 int ec_burst_disable(void)
390 {
391         if (!first_ec)
392                 return -ENODEV;
393         return acpi_ec_burst_disable(first_ec);
394 }
395
396 EXPORT_SYMBOL(ec_burst_disable);
397
398 int ec_read(u8 addr, u8 * val)
399 {
400         int err;
401         u8 temp_data;
402
403         if (!first_ec)
404                 return -ENODEV;
405
406         err = acpi_ec_read(first_ec, addr, &temp_data);
407
408         if (!err) {
409                 *val = temp_data;
410                 return 0;
411         } else
412                 return err;
413 }
414
415 EXPORT_SYMBOL(ec_read);
416
417 int ec_write(u8 addr, u8 val)
418 {
419         int err;
420
421         if (!first_ec)
422                 return -ENODEV;
423
424         err = acpi_ec_write(first_ec, addr, val);
425
426         return err;
427 }
428
429 EXPORT_SYMBOL(ec_write);
430
431 int ec_transaction(u8 command,
432                    const u8 * wdata, unsigned wdata_len,
433                    u8 * rdata, unsigned rdata_len,
434                    int force_poll)
435 {
436         struct transaction t = {.command = command,
437                                 .wdata = wdata, .rdata = rdata,
438                                 .wlen = wdata_len, .rlen = rdata_len};
439         if (!first_ec)
440                 return -ENODEV;
441
442         return acpi_ec_transaction(first_ec, &t);
443 }
444
445 EXPORT_SYMBOL(ec_transaction);
446
447 static int acpi_ec_query_unlocked(struct acpi_ec *ec, u8 * data)
448 {
449         int result;
450         u8 d;
451         struct transaction t = {.command = ACPI_EC_COMMAND_QUERY,
452                                 .wdata = NULL, .rdata = &d,
453                                 .wlen = 0, .rlen = 1};
454         if (!ec || !data)
455                 return -EINVAL;
456         /*
457          * Query the EC to find out which _Qxx method we need to evaluate.
458          * Note that successful completion of the query causes the ACPI_EC_SCI
459          * bit to be cleared (and thus clearing the interrupt source).
460          */
461         result = acpi_ec_transaction_unlocked(ec, &t);
462         if (result)
463                 return result;
464         if (!d)
465                 return -ENODATA;
466         *data = d;
467         return 0;
468 }
469
470 /* --------------------------------------------------------------------------
471                                 Event Management
472    -------------------------------------------------------------------------- */
473 int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
474                               acpi_handle handle, acpi_ec_query_func func,
475                               void *data)
476 {
477         struct acpi_ec_query_handler *handler =
478             kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL);
479         if (!handler)
480                 return -ENOMEM;
481
482         handler->query_bit = query_bit;
483         handler->handle = handle;
484         handler->func = func;
485         handler->data = data;
486         mutex_lock(&ec->lock);
487         list_add(&handler->node, &ec->list);
488         mutex_unlock(&ec->lock);
489         return 0;
490 }
491
492 EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler);
493
494 void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit)
495 {
496         struct acpi_ec_query_handler *handler, *tmp;
497         mutex_lock(&ec->lock);
498         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
499                 if (query_bit == handler->query_bit) {
500                         list_del(&handler->node);
501                         kfree(handler);
502                 }
503         }
504         mutex_unlock(&ec->lock);
505 }
506
507 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler);
508
509 static void acpi_ec_run(void *cxt)
510 {
511         struct acpi_ec_query_handler *handler = cxt;
512         if (!handler)
513                 return;
514         pr_debug(PREFIX "start query execution\n");
515         if (handler->func)
516                 handler->func(handler->data);
517         else if (handler->handle)
518                 acpi_evaluate_object(handler->handle, NULL, NULL, NULL);
519         pr_debug(PREFIX "stop query execution\n");
520         kfree(handler);
521 }
522
523 static int acpi_ec_sync_query(struct acpi_ec *ec)
524 {
525         u8 value = 0;
526         int status;
527         struct acpi_ec_query_handler *handler, *copy;
528         if ((status = acpi_ec_query_unlocked(ec, &value)))
529                 return status;
530         list_for_each_entry(handler, &ec->list, node) {
531                 if (value == handler->query_bit) {
532                         /* have custom handler for this bit */
533                         copy = kmalloc(sizeof(*handler), GFP_KERNEL);
534                         if (!copy)
535                                 return -ENOMEM;
536                         memcpy(copy, handler, sizeof(*copy));
537                         pr_debug(PREFIX "push query execution (0x%2x) on queue\n", value);
538                         return acpi_os_execute(OSL_GPE_HANDLER,
539                                 acpi_ec_run, copy);
540                 }
541         }
542         return 0;
543 }
544
545 static void acpi_ec_gpe_query(void *ec_cxt)
546 {
547         struct acpi_ec *ec = ec_cxt;
548         if (!ec)
549                 return;
550         mutex_lock(&ec->lock);
551         acpi_ec_sync_query(ec);
552         mutex_unlock(&ec->lock);
553 }
554
555 static void acpi_ec_gpe_query(void *ec_cxt);
556
557 static int ec_check_sci(struct acpi_ec *ec, u8 state)
558 {
559         if (state & ACPI_EC_FLAG_SCI) {
560                 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) {
561                         pr_debug(PREFIX "push gpe query to the queue\n");
562                         return acpi_os_execute(OSL_NOTIFY_HANDLER,
563                                 acpi_ec_gpe_query, ec);
564                 }
565         }
566         return 0;
567 }
568
569 static u32 acpi_ec_gpe_handler(void *data)
570 {
571         struct acpi_ec *ec = data;
572
573         pr_debug(PREFIX "~~~> interrupt\n");
574
575         advance_transaction(ec, acpi_ec_read_status(ec));
576         if (ec_transaction_done(ec) &&
577             (acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF) == 0) {
578                 wake_up(&ec->wait);
579                 ec_check_sci(ec, acpi_ec_read_status(ec));
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         if (EC_FLAGS_MSI)
607                 acpi_ec_burst_enable(ec);
608
609         if (function == ACPI_READ) {
610                 result = acpi_ec_read(ec, address, &temp);
611                 *value = temp;
612         } else {
613                 temp = 0xff & (*value);
614                 result = acpi_ec_write(ec, address, temp);
615         }
616
617         for (i = 8; unlikely(bits - i > 0); i += 8) {
618                 ++address;
619                 if (function == ACPI_READ) {
620                         result = acpi_ec_read(ec, address, &temp);
621                         (*value) |= ((acpi_integer)temp) << i;
622                 } else {
623                         temp = 0xff & ((*value) >> i);
624                         result = acpi_ec_write(ec, address, temp);
625                 }
626         }
627
628         if (EC_FLAGS_MSI)
629                 acpi_ec_burst_disable(ec);
630
631         switch (result) {
632         case -EINVAL:
633                 return AE_BAD_PARAMETER;
634                 break;
635         case -ENODEV:
636                 return AE_NOT_FOUND;
637                 break;
638         case -ETIME:
639                 return AE_TIME;
640                 break;
641         default:
642                 return AE_OK;
643         }
644 }
645
646 /* --------------------------------------------------------------------------
647                               FS Interface (/proc)
648    -------------------------------------------------------------------------- */
649
650 static struct proc_dir_entry *acpi_ec_dir;
651
652 static int acpi_ec_read_info(struct seq_file *seq, void *offset)
653 {
654         struct acpi_ec *ec = seq->private;
655
656         if (!ec)
657                 goto end;
658
659         seq_printf(seq, "gpe:\t\t\t0x%02x\n", (u32) ec->gpe);
660         seq_printf(seq, "ports:\t\t\t0x%02x, 0x%02x\n",
661                    (unsigned)ec->command_addr, (unsigned)ec->data_addr);
662         seq_printf(seq, "use global lock:\t%s\n",
663                    ec->global_lock ? "yes" : "no");
664       end:
665         return 0;
666 }
667
668 static int acpi_ec_info_open_fs(struct inode *inode, struct file *file)
669 {
670         return single_open(file, acpi_ec_read_info, PDE(inode)->data);
671 }
672
673 static const struct file_operations acpi_ec_info_ops = {
674         .open = acpi_ec_info_open_fs,
675         .read = seq_read,
676         .llseek = seq_lseek,
677         .release = single_release,
678         .owner = THIS_MODULE,
679 };
680
681 static int acpi_ec_add_fs(struct acpi_device *device)
682 {
683         struct proc_dir_entry *entry = NULL;
684
685         if (!acpi_device_dir(device)) {
686                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
687                                                      acpi_ec_dir);
688                 if (!acpi_device_dir(device))
689                         return -ENODEV;
690         }
691
692         entry = proc_create_data(ACPI_EC_FILE_INFO, S_IRUGO,
693                                  acpi_device_dir(device),
694                                  &acpi_ec_info_ops, acpi_driver_data(device));
695         if (!entry)
696                 return -ENODEV;
697         return 0;
698 }
699
700 static int acpi_ec_remove_fs(struct acpi_device *device)
701 {
702
703         if (acpi_device_dir(device)) {
704                 remove_proc_entry(ACPI_EC_FILE_INFO, acpi_device_dir(device));
705                 remove_proc_entry(acpi_device_bid(device), acpi_ec_dir);
706                 acpi_device_dir(device) = NULL;
707         }
708
709         return 0;
710 }
711
712 /* --------------------------------------------------------------------------
713                                Driver Interface
714    -------------------------------------------------------------------------- */
715 static acpi_status
716 ec_parse_io_ports(struct acpi_resource *resource, void *context);
717
718 static struct acpi_ec *make_acpi_ec(void)
719 {
720         struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
721         if (!ec)
722                 return NULL;
723         ec->flags = 1 << EC_FLAGS_QUERY_PENDING;
724         mutex_init(&ec->lock);
725         init_waitqueue_head(&ec->wait);
726         INIT_LIST_HEAD(&ec->list);
727         spin_lock_init(&ec->curr_lock);
728         return ec;
729 }
730
731 static acpi_status
732 acpi_ec_register_query_methods(acpi_handle handle, u32 level,
733                                void *context, void **return_value)
734 {
735         char node_name[5];
736         struct acpi_buffer buffer = { sizeof(node_name), node_name };
737         struct acpi_ec *ec = context;
738         int value = 0;
739         acpi_status status;
740
741         status = acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
742
743         if (ACPI_SUCCESS(status) && sscanf(node_name, "_Q%x", &value) == 1) {
744                 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL);
745         }
746         return AE_OK;
747 }
748
749 static acpi_status
750 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
751 {
752         acpi_status status;
753         unsigned long long tmp = 0;
754
755         struct acpi_ec *ec = context;
756
757         /* clear addr values, ec_parse_io_ports depend on it */
758         ec->command_addr = ec->data_addr = 0;
759
760         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
761                                      ec_parse_io_ports, ec);
762         if (ACPI_FAILURE(status))
763                 return status;
764
765         /* Get GPE bit assignment (EC events). */
766         /* TODO: Add support for _GPE returning a package */
767         status = acpi_evaluate_integer(handle, "_GPE", NULL, &tmp);
768         if (ACPI_FAILURE(status))
769                 return status;
770         ec->gpe = tmp;
771         /* Use the global lock for all EC transactions? */
772         tmp = 0;
773         acpi_evaluate_integer(handle, "_GLK", NULL, &tmp);
774         ec->global_lock = tmp;
775         ec->handle = handle;
776         return AE_CTRL_TERMINATE;
777 }
778
779 static int ec_install_handlers(struct acpi_ec *ec)
780 {
781         acpi_status status;
782         if (test_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags))
783                 return 0;
784         status = acpi_install_gpe_handler(NULL, ec->gpe,
785                                   ACPI_GPE_EDGE_TRIGGERED,
786                                   &acpi_ec_gpe_handler, ec);
787         if (ACPI_FAILURE(status))
788                 return -ENODEV;
789         acpi_set_gpe_type(NULL, ec->gpe, ACPI_GPE_TYPE_RUNTIME);
790         acpi_enable_gpe(NULL, ec->gpe);
791         status = acpi_install_address_space_handler(ec->handle,
792                                                     ACPI_ADR_SPACE_EC,
793                                                     &acpi_ec_space_handler,
794                                                     NULL, ec);
795         if (ACPI_FAILURE(status)) {
796                 if (status == AE_NOT_FOUND) {
797                         /*
798                          * Maybe OS fails in evaluating the _REG object.
799                          * The AE_NOT_FOUND error will be ignored and OS
800                          * continue to initialize EC.
801                          */
802                         printk(KERN_ERR "Fail in evaluating the _REG object"
803                                 " of EC device. Broken bios is suspected.\n");
804                 } else {
805                         acpi_remove_gpe_handler(NULL, ec->gpe,
806                                 &acpi_ec_gpe_handler);
807                         return -ENODEV;
808                 }
809         }
810
811         set_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
812         return 0;
813 }
814
815 static void ec_remove_handlers(struct acpi_ec *ec)
816 {
817         if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle,
818                                 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler)))
819                 pr_err(PREFIX "failed to remove space handler\n");
820         if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe,
821                                 &acpi_ec_gpe_handler)))
822                 pr_err(PREFIX "failed to remove gpe handler\n");
823         clear_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
824 }
825
826 static int acpi_ec_add(struct acpi_device *device)
827 {
828         struct acpi_ec *ec = NULL;
829         int ret;
830
831         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
832         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
833
834         /* Check for boot EC */
835         if (boot_ec &&
836             (boot_ec->handle == device->handle ||
837              boot_ec->handle == ACPI_ROOT_OBJECT)) {
838                 ec = boot_ec;
839                 boot_ec = NULL;
840         } else {
841                 ec = make_acpi_ec();
842                 if (!ec)
843                         return -ENOMEM;
844         }
845         if (ec_parse_device(device->handle, 0, ec, NULL) !=
846                 AE_CTRL_TERMINATE) {
847                         kfree(ec);
848                         return -EINVAL;
849         }
850
851         ec->handle = device->handle;
852
853         /* Find and register all query methods */
854         acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1,
855                             acpi_ec_register_query_methods, NULL, ec, NULL);
856
857         if (!first_ec)
858                 first_ec = ec;
859         device->driver_data = ec;
860         acpi_ec_add_fs(device);
861         pr_info(PREFIX "GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n",
862                           ec->gpe, ec->command_addr, ec->data_addr);
863
864         ret = ec_install_handlers(ec);
865
866         /* EC is fully operational, allow queries */
867         clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
868         return ret;
869 }
870
871 static int acpi_ec_remove(struct acpi_device *device, int type)
872 {
873         struct acpi_ec *ec;
874         struct acpi_ec_query_handler *handler, *tmp;
875
876         if (!device)
877                 return -EINVAL;
878
879         ec = acpi_driver_data(device);
880         ec_remove_handlers(ec);
881         mutex_lock(&ec->lock);
882         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
883                 list_del(&handler->node);
884                 kfree(handler);
885         }
886         mutex_unlock(&ec->lock);
887         acpi_ec_remove_fs(device);
888         device->driver_data = NULL;
889         if (ec == first_ec)
890                 first_ec = NULL;
891         kfree(ec);
892         return 0;
893 }
894
895 static acpi_status
896 ec_parse_io_ports(struct acpi_resource *resource, void *context)
897 {
898         struct acpi_ec *ec = context;
899
900         if (resource->type != ACPI_RESOURCE_TYPE_IO)
901                 return AE_OK;
902
903         /*
904          * The first address region returned is the data port, and
905          * the second address region returned is the status/command
906          * port.
907          */
908         if (ec->data_addr == 0)
909                 ec->data_addr = resource->data.io.minimum;
910         else if (ec->command_addr == 0)
911                 ec->command_addr = resource->data.io.minimum;
912         else
913                 return AE_CTRL_TERMINATE;
914
915         return AE_OK;
916 }
917
918 int __init acpi_boot_ec_enable(void)
919 {
920         if (!boot_ec || test_bit(EC_FLAGS_HANDLERS_INSTALLED, &boot_ec->flags))
921                 return 0;
922         if (!ec_install_handlers(boot_ec)) {
923                 first_ec = boot_ec;
924                 return 0;
925         }
926         return -EFAULT;
927 }
928
929 static const struct acpi_device_id ec_device_ids[] = {
930         {"PNP0C09", 0},
931         {"", 0},
932 };
933
934 /* Some BIOS do not survive early DSDT scan, skip it */
935 static int ec_skip_dsdt_scan(const struct dmi_system_id *id)
936 {
937         EC_FLAGS_SKIP_DSDT_SCAN = 1;
938         return 0;
939 }
940
941 /* ASUStek often supplies us with broken ECDT, validate it */
942 static int ec_validate_ecdt(const struct dmi_system_id *id)
943 {
944         EC_FLAGS_VALIDATE_ECDT = 1;
945         return 0;
946 }
947
948 /* MSI EC needs special treatment, enable it */
949 static int ec_flag_msi(const struct dmi_system_id *id)
950 {
951         printk(KERN_DEBUG PREFIX "Detected MSI hardware, enabling workarounds.\n");
952         EC_FLAGS_MSI = 1;
953         EC_FLAGS_VALIDATE_ECDT = 1;
954         return 0;
955 }
956
957 static struct dmi_system_id __initdata ec_dmi_table[] = {
958         {
959         ec_skip_dsdt_scan, "Compal JFL92", {
960         DMI_MATCH(DMI_BIOS_VENDOR, "COMPAL"),
961         DMI_MATCH(DMI_BOARD_NAME, "JFL92") }, NULL},
962         {
963         ec_flag_msi, "MSI hardware", {
964         DMI_MATCH(DMI_BIOS_VENDOR, "Micro-Star")}, NULL},
965         {
966         ec_flag_msi, "MSI hardware", {
967         DMI_MATCH(DMI_SYS_VENDOR, "Micro-Star")}, NULL},
968         {
969         ec_flag_msi, "MSI hardware", {
970         DMI_MATCH(DMI_CHASSIS_VENDOR, "MICRO-Star")}, NULL},
971         {
972         ec_validate_ecdt, "ASUS hardware", {
973         DMI_MATCH(DMI_BIOS_VENDOR, "ASUS") }, NULL},
974         {},
975 };
976
977
978 int __init acpi_ec_ecdt_probe(void)
979 {
980         acpi_status status;
981         struct acpi_ec *saved_ec = NULL;
982         struct acpi_table_ecdt *ecdt_ptr;
983
984         boot_ec = make_acpi_ec();
985         if (!boot_ec)
986                 return -ENOMEM;
987         /*
988          * Generate a boot ec context
989          */
990         dmi_check_system(ec_dmi_table);
991         status = acpi_get_table(ACPI_SIG_ECDT, 1,
992                                 (struct acpi_table_header **)&ecdt_ptr);
993         if (ACPI_SUCCESS(status)) {
994                 pr_info(PREFIX "EC description table is found, configuring boot EC\n");
995                 boot_ec->command_addr = ecdt_ptr->control.address;
996                 boot_ec->data_addr = ecdt_ptr->data.address;
997                 boot_ec->gpe = ecdt_ptr->gpe;
998                 boot_ec->handle = ACPI_ROOT_OBJECT;
999                 acpi_get_handle(ACPI_ROOT_OBJECT, ecdt_ptr->id, &boot_ec->handle);
1000                 /* Don't trust ECDT, which comes from ASUSTek */
1001                 if (!EC_FLAGS_VALIDATE_ECDT)
1002                         goto install;
1003                 saved_ec = kmalloc(sizeof(struct acpi_ec), GFP_KERNEL);
1004                 if (!saved_ec)
1005                         return -ENOMEM;
1006                 memcpy(saved_ec, boot_ec, sizeof(struct acpi_ec));
1007         /* fall through */
1008         }
1009
1010         if (EC_FLAGS_SKIP_DSDT_SCAN)
1011                 return -ENODEV;
1012
1013         /* This workaround is needed only on some broken machines,
1014          * which require early EC, but fail to provide ECDT */
1015         printk(KERN_DEBUG PREFIX "Look up EC in DSDT\n");
1016         status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device,
1017                                         boot_ec, NULL);
1018         /* Check that acpi_get_devices actually find something */
1019         if (ACPI_FAILURE(status) || !boot_ec->handle)
1020                 goto error;
1021         if (saved_ec) {
1022                 /* try to find good ECDT from ASUSTek */
1023                 if (saved_ec->command_addr != boot_ec->command_addr ||
1024                     saved_ec->data_addr != boot_ec->data_addr ||
1025                     saved_ec->gpe != boot_ec->gpe ||
1026                     saved_ec->handle != boot_ec->handle)
1027                         pr_info(PREFIX "ASUSTek keeps feeding us with broken "
1028                         "ECDT tables, which are very hard to workaround. "
1029                         "Trying to use DSDT EC info instead. Please send "
1030                         "output of acpidump to linux-acpi@vger.kernel.org\n");
1031                 kfree(saved_ec);
1032                 saved_ec = NULL;
1033         } else {
1034                 /* We really need to limit this workaround, the only ASUS,
1035                 * which needs it, has fake EC._INI method, so use it as flag.
1036                 * Keep boot_ec struct as it will be needed soon.
1037                 */
1038                 acpi_handle dummy;
1039                 if (!dmi_name_in_vendors("ASUS") ||
1040                     ACPI_FAILURE(acpi_get_handle(boot_ec->handle, "_INI",
1041                                                         &dummy)))
1042                         return -ENODEV;
1043         }
1044 install:
1045         if (!ec_install_handlers(boot_ec)) {
1046                 first_ec = boot_ec;
1047                 return 0;
1048         }
1049 error:
1050         kfree(boot_ec);
1051         boot_ec = NULL;
1052         return -ENODEV;
1053 }
1054
1055 static int acpi_ec_suspend(struct acpi_device *device, pm_message_t state)
1056 {
1057         struct acpi_ec *ec = acpi_driver_data(device);
1058         /* Stop using GPE */
1059         acpi_disable_gpe(NULL, ec->gpe);
1060         return 0;
1061 }
1062
1063 static int acpi_ec_resume(struct acpi_device *device)
1064 {
1065         struct acpi_ec *ec = acpi_driver_data(device);
1066         /* Enable use of GPE back */
1067         acpi_enable_gpe(NULL, ec->gpe);
1068         return 0;
1069 }
1070
1071 static struct acpi_driver acpi_ec_driver = {
1072         .name = "ec",
1073         .class = ACPI_EC_CLASS,
1074         .ids = ec_device_ids,
1075         .ops = {
1076                 .add = acpi_ec_add,
1077                 .remove = acpi_ec_remove,
1078                 .suspend = acpi_ec_suspend,
1079                 .resume = acpi_ec_resume,
1080                 },
1081 };
1082
1083 int __init acpi_ec_init(void)
1084 {
1085         int result = 0;
1086
1087         acpi_ec_dir = proc_mkdir(ACPI_EC_CLASS, acpi_root_dir);
1088         if (!acpi_ec_dir)
1089                 return -ENODEV;
1090
1091         /* Now register the driver for the EC */
1092         result = acpi_bus_register_driver(&acpi_ec_driver);
1093         if (result < 0) {
1094                 remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1095                 return -ENODEV;
1096         }
1097
1098         return result;
1099 }
1100
1101 /* EC driver currently not unloadable */
1102 #if 0
1103 static void __exit acpi_ec_exit(void)
1104 {
1105
1106         acpi_bus_unregister_driver(&acpi_ec_driver);
1107
1108         remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1109
1110         return;
1111 }
1112 #endif  /* 0 */