d6471bb6852fb58802a5c9153dcb63fb2c642429
[linux-3.10.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         spin_lock_irqsave(&ec->curr_lock, tmp);
263         ec->curr = NULL;
264         spin_unlock_irqrestore(&ec->curr_lock, tmp);
265         return ret;
266 }
267
268 static int ec_check_ibf0(struct acpi_ec *ec)
269 {
270         u8 status = acpi_ec_read_status(ec);
271         return (status & ACPI_EC_FLAG_IBF) == 0;
272 }
273
274 static int ec_wait_ibf0(struct acpi_ec *ec)
275 {
276         unsigned long delay = jiffies + msecs_to_jiffies(ACPI_EC_DELAY);
277         /* interrupt wait manually if GPE mode is not active */
278         while (time_before(jiffies, delay))
279                 if (wait_event_timeout(ec->wait, ec_check_ibf0(ec),
280                                         msecs_to_jiffies(1)))
281                         return 0;
282         return -ETIME;
283 }
284
285 static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t)
286 {
287         int status;
288         u32 glk;
289         if (!ec || (!t) || (t->wlen && !t->wdata) || (t->rlen && !t->rdata))
290                 return -EINVAL;
291         if (t->rdata)
292                 memset(t->rdata, 0, t->rlen);
293         mutex_lock(&ec->lock);
294         if (ec->global_lock) {
295                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
296                 if (ACPI_FAILURE(status)) {
297                         status = -ENODEV;
298                         goto unlock;
299                 }
300         }
301         if (ec_wait_ibf0(ec)) {
302                 pr_err(PREFIX "input buffer is not empty, "
303                                 "aborting transaction\n");
304                 status = -ETIME;
305                 goto end;
306         }
307         pr_debug(PREFIX "transaction start\n");
308         /* disable GPE during transaction if storm is detected */
309         if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
310                 acpi_disable_gpe(NULL, ec->gpe);
311         }
312
313         status = acpi_ec_transaction_unlocked(ec, t);
314
315         /* check if we received SCI during transaction */
316         ec_check_sci_sync(ec, acpi_ec_read_status(ec));
317         if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
318                 msleep(1);
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         pr_debug(PREFIX "transaction end\n");
327 end:
328         if (ec->global_lock)
329                 acpi_release_global_lock(glk);
330 unlock:
331         mutex_unlock(&ec->lock);
332         return status;
333 }
334
335 static int acpi_ec_burst_enable(struct acpi_ec *ec)
336 {
337         u8 d;
338         struct transaction t = {.command = ACPI_EC_BURST_ENABLE,
339                                 .wdata = NULL, .rdata = &d,
340                                 .wlen = 0, .rlen = 1};
341
342         return acpi_ec_transaction(ec, &t);
343 }
344
345 static int acpi_ec_burst_disable(struct acpi_ec *ec)
346 {
347         struct transaction t = {.command = ACPI_EC_BURST_DISABLE,
348                                 .wdata = NULL, .rdata = NULL,
349                                 .wlen = 0, .rlen = 0};
350
351         return (acpi_ec_read_status(ec) & ACPI_EC_FLAG_BURST) ?
352                                 acpi_ec_transaction(ec, &t) : 0;
353 }
354
355 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 * data)
356 {
357         int result;
358         u8 d;
359         struct transaction t = {.command = ACPI_EC_COMMAND_READ,
360                                 .wdata = &address, .rdata = &d,
361                                 .wlen = 1, .rlen = 1};
362
363         result = acpi_ec_transaction(ec, &t);
364         *data = d;
365         return result;
366 }
367
368 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
369 {
370         u8 wdata[2] = { address, data };
371         struct transaction t = {.command = ACPI_EC_COMMAND_WRITE,
372                                 .wdata = wdata, .rdata = NULL,
373                                 .wlen = 2, .rlen = 0};
374
375         return acpi_ec_transaction(ec, &t);
376 }
377
378 /*
379  * Externally callable EC access functions. For now, assume 1 EC only
380  */
381 int ec_burst_enable(void)
382 {
383         if (!first_ec)
384                 return -ENODEV;
385         return acpi_ec_burst_enable(first_ec);
386 }
387
388 EXPORT_SYMBOL(ec_burst_enable);
389
390 int ec_burst_disable(void)
391 {
392         if (!first_ec)
393                 return -ENODEV;
394         return acpi_ec_burst_disable(first_ec);
395 }
396
397 EXPORT_SYMBOL(ec_burst_disable);
398
399 int ec_read(u8 addr, u8 * val)
400 {
401         int err;
402         u8 temp_data;
403
404         if (!first_ec)
405                 return -ENODEV;
406
407         err = acpi_ec_read(first_ec, addr, &temp_data);
408
409         if (!err) {
410                 *val = temp_data;
411                 return 0;
412         } else
413                 return err;
414 }
415
416 EXPORT_SYMBOL(ec_read);
417
418 int ec_write(u8 addr, u8 val)
419 {
420         int err;
421
422         if (!first_ec)
423                 return -ENODEV;
424
425         err = acpi_ec_write(first_ec, addr, val);
426
427         return err;
428 }
429
430 EXPORT_SYMBOL(ec_write);
431
432 int ec_transaction(u8 command,
433                    const u8 * wdata, unsigned wdata_len,
434                    u8 * rdata, unsigned rdata_len,
435                    int force_poll)
436 {
437         struct transaction t = {.command = command,
438                                 .wdata = wdata, .rdata = rdata,
439                                 .wlen = wdata_len, .rlen = rdata_len};
440         if (!first_ec)
441                 return -ENODEV;
442
443         return acpi_ec_transaction(first_ec, &t);
444 }
445
446 EXPORT_SYMBOL(ec_transaction);
447
448 static int acpi_ec_query_unlocked(struct acpi_ec *ec, u8 * data)
449 {
450         int result;
451         u8 d;
452         struct transaction t = {.command = ACPI_EC_COMMAND_QUERY,
453                                 .wdata = NULL, .rdata = &d,
454                                 .wlen = 0, .rlen = 1};
455         if (!ec || !data)
456                 return -EINVAL;
457         /*
458          * Query the EC to find out which _Qxx method we need to evaluate.
459          * Note that successful completion of the query causes the ACPI_EC_SCI
460          * bit to be cleared (and thus clearing the interrupt source).
461          */
462         result = acpi_ec_transaction_unlocked(ec, &t);
463         if (result)
464                 return result;
465         if (!d)
466                 return -ENODATA;
467         *data = d;
468         return 0;
469 }
470
471 /* --------------------------------------------------------------------------
472                                 Event Management
473    -------------------------------------------------------------------------- */
474 int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
475                               acpi_handle handle, acpi_ec_query_func func,
476                               void *data)
477 {
478         struct acpi_ec_query_handler *handler =
479             kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL);
480         if (!handler)
481                 return -ENOMEM;
482
483         handler->query_bit = query_bit;
484         handler->handle = handle;
485         handler->func = func;
486         handler->data = data;
487         mutex_lock(&ec->lock);
488         list_add(&handler->node, &ec->list);
489         mutex_unlock(&ec->lock);
490         return 0;
491 }
492
493 EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler);
494
495 void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit)
496 {
497         struct acpi_ec_query_handler *handler, *tmp;
498         mutex_lock(&ec->lock);
499         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
500                 if (query_bit == handler->query_bit) {
501                         list_del(&handler->node);
502                         kfree(handler);
503                 }
504         }
505         mutex_unlock(&ec->lock);
506 }
507
508 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler);
509
510 static void acpi_ec_run(void *cxt)
511 {
512         struct acpi_ec_query_handler *handler = cxt;
513         if (!handler)
514                 return;
515         pr_debug(PREFIX "start query execution\n");
516         if (handler->func)
517                 handler->func(handler->data);
518         else if (handler->handle)
519                 acpi_evaluate_object(handler->handle, NULL, NULL, NULL);
520         pr_debug(PREFIX "stop query execution\n");
521         kfree(handler);
522 }
523
524 static int acpi_ec_sync_query(struct acpi_ec *ec)
525 {
526         u8 value = 0;
527         int status;
528         struct acpi_ec_query_handler *handler, *copy;
529         if ((status = acpi_ec_query_unlocked(ec, &value)))
530                 return status;
531         list_for_each_entry(handler, &ec->list, node) {
532                 if (value == handler->query_bit) {
533                         /* have custom handler for this bit */
534                         copy = kmalloc(sizeof(*handler), GFP_KERNEL);
535                         if (!copy)
536                                 return -ENOMEM;
537                         memcpy(copy, handler, sizeof(*copy));
538                         pr_debug(PREFIX "push query execution (0x%2x) on queue\n", value);
539                         return acpi_os_execute((copy->func) ?
540                                 OSL_NOTIFY_HANDLER : OSL_GPE_HANDLER,
541                                 acpi_ec_run, copy);
542                 }
543         }
544         return 0;
545 }
546
547 static void acpi_ec_gpe_query(void *ec_cxt)
548 {
549         struct acpi_ec *ec = ec_cxt;
550         if (!ec)
551                 return;
552         mutex_lock(&ec->lock);
553         acpi_ec_sync_query(ec);
554         mutex_unlock(&ec->lock);
555 }
556
557 static void acpi_ec_gpe_query(void *ec_cxt);
558
559 static int ec_check_sci(struct acpi_ec *ec, u8 state)
560 {
561         if (state & ACPI_EC_FLAG_SCI) {
562                 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags)) {
563                         pr_debug(PREFIX "push gpe query to the queue\n");
564                         return acpi_os_execute(OSL_NOTIFY_HANDLER,
565                                 acpi_ec_gpe_query, ec);
566                 }
567         }
568         return 0;
569 }
570
571 static u32 acpi_ec_gpe_handler(void *data)
572 {
573         struct acpi_ec *ec = data;
574
575         pr_debug(PREFIX "~~~> interrupt\n");
576
577         advance_transaction(ec, acpi_ec_read_status(ec));
578         if (ec_transaction_done(ec) &&
579             (acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF) == 0) {
580                 wake_up(&ec->wait);
581                 ec_check_sci(ec, acpi_ec_read_status(ec));
582         }
583         return ACPI_INTERRUPT_HANDLED;
584 }
585
586 /* --------------------------------------------------------------------------
587                              Address Space Management
588    -------------------------------------------------------------------------- */
589
590 static acpi_status
591 acpi_ec_space_handler(u32 function, acpi_physical_address address,
592                       u32 bits, acpi_integer *value,
593                       void *handler_context, void *region_context)
594 {
595         struct acpi_ec *ec = handler_context;
596         int result = 0, i;
597         u8 temp = 0;
598
599         if ((address > 0xFF) || !value || !handler_context)
600                 return AE_BAD_PARAMETER;
601
602         if (function != ACPI_READ && function != ACPI_WRITE)
603                 return AE_BAD_PARAMETER;
604
605         if (bits != 8 && acpi_strict)
606                 return AE_BAD_PARAMETER;
607
608         if (EC_FLAGS_MSI)
609                 acpi_ec_burst_enable(ec);
610
611         if (function == ACPI_READ) {
612                 result = acpi_ec_read(ec, address, &temp);
613                 *value = temp;
614         } else {
615                 temp = 0xff & (*value);
616                 result = acpi_ec_write(ec, address, temp);
617         }
618
619         for (i = 8; unlikely(bits - i > 0); i += 8) {
620                 ++address;
621                 if (function == ACPI_READ) {
622                         result = acpi_ec_read(ec, address, &temp);
623                         (*value) |= ((acpi_integer)temp) << i;
624                 } else {
625                         temp = 0xff & ((*value) >> i);
626                         result = acpi_ec_write(ec, address, temp);
627                 }
628         }
629
630         if (EC_FLAGS_MSI)
631                 acpi_ec_burst_disable(ec);
632
633         switch (result) {
634         case -EINVAL:
635                 return AE_BAD_PARAMETER;
636                 break;
637         case -ENODEV:
638                 return AE_NOT_FOUND;
639                 break;
640         case -ETIME:
641                 return AE_TIME;
642                 break;
643         default:
644                 return AE_OK;
645         }
646 }
647
648 /* --------------------------------------------------------------------------
649                               FS Interface (/proc)
650    -------------------------------------------------------------------------- */
651
652 static struct proc_dir_entry *acpi_ec_dir;
653
654 static int acpi_ec_read_info(struct seq_file *seq, void *offset)
655 {
656         struct acpi_ec *ec = seq->private;
657
658         if (!ec)
659                 goto end;
660
661         seq_printf(seq, "gpe:\t\t\t0x%02x\n", (u32) ec->gpe);
662         seq_printf(seq, "ports:\t\t\t0x%02x, 0x%02x\n",
663                    (unsigned)ec->command_addr, (unsigned)ec->data_addr);
664         seq_printf(seq, "use global lock:\t%s\n",
665                    ec->global_lock ? "yes" : "no");
666       end:
667         return 0;
668 }
669
670 static int acpi_ec_info_open_fs(struct inode *inode, struct file *file)
671 {
672         return single_open(file, acpi_ec_read_info, PDE(inode)->data);
673 }
674
675 static const struct file_operations acpi_ec_info_ops = {
676         .open = acpi_ec_info_open_fs,
677         .read = seq_read,
678         .llseek = seq_lseek,
679         .release = single_release,
680         .owner = THIS_MODULE,
681 };
682
683 static int acpi_ec_add_fs(struct acpi_device *device)
684 {
685         struct proc_dir_entry *entry = NULL;
686
687         if (!acpi_device_dir(device)) {
688                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
689                                                      acpi_ec_dir);
690                 if (!acpi_device_dir(device))
691                         return -ENODEV;
692         }
693
694         entry = proc_create_data(ACPI_EC_FILE_INFO, S_IRUGO,
695                                  acpi_device_dir(device),
696                                  &acpi_ec_info_ops, acpi_driver_data(device));
697         if (!entry)
698                 return -ENODEV;
699         return 0;
700 }
701
702 static int acpi_ec_remove_fs(struct acpi_device *device)
703 {
704
705         if (acpi_device_dir(device)) {
706                 remove_proc_entry(ACPI_EC_FILE_INFO, acpi_device_dir(device));
707                 remove_proc_entry(acpi_device_bid(device), acpi_ec_dir);
708                 acpi_device_dir(device) = NULL;
709         }
710
711         return 0;
712 }
713
714 /* --------------------------------------------------------------------------
715                                Driver Interface
716    -------------------------------------------------------------------------- */
717 static acpi_status
718 ec_parse_io_ports(struct acpi_resource *resource, void *context);
719
720 static struct acpi_ec *make_acpi_ec(void)
721 {
722         struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
723         if (!ec)
724                 return NULL;
725         ec->flags = 1 << EC_FLAGS_QUERY_PENDING;
726         mutex_init(&ec->lock);
727         init_waitqueue_head(&ec->wait);
728         INIT_LIST_HEAD(&ec->list);
729         spin_lock_init(&ec->curr_lock);
730         return ec;
731 }
732
733 static acpi_status
734 acpi_ec_register_query_methods(acpi_handle handle, u32 level,
735                                void *context, void **return_value)
736 {
737         char node_name[5];
738         struct acpi_buffer buffer = { sizeof(node_name), node_name };
739         struct acpi_ec *ec = context;
740         int value = 0;
741         acpi_status status;
742
743         status = acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
744
745         if (ACPI_SUCCESS(status) && sscanf(node_name, "_Q%x", &value) == 1) {
746                 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL);
747         }
748         return AE_OK;
749 }
750
751 static acpi_status
752 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
753 {
754         acpi_status status;
755         unsigned long long tmp = 0;
756
757         struct acpi_ec *ec = context;
758
759         /* clear addr values, ec_parse_io_ports depend on it */
760         ec->command_addr = ec->data_addr = 0;
761
762         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
763                                      ec_parse_io_ports, ec);
764         if (ACPI_FAILURE(status))
765                 return status;
766
767         /* Get GPE bit assignment (EC events). */
768         /* TODO: Add support for _GPE returning a package */
769         status = acpi_evaluate_integer(handle, "_GPE", NULL, &tmp);
770         if (ACPI_FAILURE(status))
771                 return status;
772         ec->gpe = tmp;
773         /* Use the global lock for all EC transactions? */
774         tmp = 0;
775         acpi_evaluate_integer(handle, "_GLK", NULL, &tmp);
776         ec->global_lock = tmp;
777         ec->handle = handle;
778         return AE_CTRL_TERMINATE;
779 }
780
781 static int ec_install_handlers(struct acpi_ec *ec)
782 {
783         acpi_status status;
784         if (test_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags))
785                 return 0;
786         status = acpi_install_gpe_handler(NULL, ec->gpe,
787                                   ACPI_GPE_EDGE_TRIGGERED,
788                                   &acpi_ec_gpe_handler, ec);
789         if (ACPI_FAILURE(status))
790                 return -ENODEV;
791         acpi_set_gpe_type(NULL, ec->gpe, ACPI_GPE_TYPE_RUNTIME);
792         acpi_enable_gpe(NULL, ec->gpe);
793         status = acpi_install_address_space_handler(ec->handle,
794                                                     ACPI_ADR_SPACE_EC,
795                                                     &acpi_ec_space_handler,
796                                                     NULL, ec);
797         if (ACPI_FAILURE(status)) {
798                 if (status == AE_NOT_FOUND) {
799                         /*
800                          * Maybe OS fails in evaluating the _REG object.
801                          * The AE_NOT_FOUND error will be ignored and OS
802                          * continue to initialize EC.
803                          */
804                         printk(KERN_ERR "Fail in evaluating the _REG object"
805                                 " of EC device. Broken bios is suspected.\n");
806                 } else {
807                         acpi_remove_gpe_handler(NULL, ec->gpe,
808                                 &acpi_ec_gpe_handler);
809                         return -ENODEV;
810                 }
811         }
812
813         set_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
814         return 0;
815 }
816
817 static void ec_remove_handlers(struct acpi_ec *ec)
818 {
819         if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle,
820                                 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler)))
821                 pr_err(PREFIX "failed to remove space handler\n");
822         if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe,
823                                 &acpi_ec_gpe_handler)))
824                 pr_err(PREFIX "failed to remove gpe handler\n");
825         clear_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
826 }
827
828 static int acpi_ec_add(struct acpi_device *device)
829 {
830         struct acpi_ec *ec = NULL;
831         int ret;
832
833         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
834         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
835
836         /* Check for boot EC */
837         if (boot_ec &&
838             (boot_ec->handle == device->handle ||
839              boot_ec->handle == ACPI_ROOT_OBJECT)) {
840                 ec = boot_ec;
841                 boot_ec = NULL;
842         } else {
843                 ec = make_acpi_ec();
844                 if (!ec)
845                         return -ENOMEM;
846         }
847         if (ec_parse_device(device->handle, 0, ec, NULL) !=
848                 AE_CTRL_TERMINATE) {
849                         kfree(ec);
850                         return -EINVAL;
851         }
852
853         ec->handle = device->handle;
854
855         /* Find and register all query methods */
856         acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1,
857                             acpi_ec_register_query_methods, NULL, ec, NULL);
858
859         if (!first_ec)
860                 first_ec = ec;
861         device->driver_data = ec;
862         acpi_ec_add_fs(device);
863         pr_info(PREFIX "GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n",
864                           ec->gpe, ec->command_addr, ec->data_addr);
865
866         ret = ec_install_handlers(ec);
867
868         /* EC is fully operational, allow queries */
869         clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
870         return ret;
871 }
872
873 static int acpi_ec_remove(struct acpi_device *device, int type)
874 {
875         struct acpi_ec *ec;
876         struct acpi_ec_query_handler *handler, *tmp;
877
878         if (!device)
879                 return -EINVAL;
880
881         ec = acpi_driver_data(device);
882         ec_remove_handlers(ec);
883         mutex_lock(&ec->lock);
884         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
885                 list_del(&handler->node);
886                 kfree(handler);
887         }
888         mutex_unlock(&ec->lock);
889         acpi_ec_remove_fs(device);
890         device->driver_data = NULL;
891         if (ec == first_ec)
892                 first_ec = NULL;
893         kfree(ec);
894         return 0;
895 }
896
897 static acpi_status
898 ec_parse_io_ports(struct acpi_resource *resource, void *context)
899 {
900         struct acpi_ec *ec = context;
901
902         if (resource->type != ACPI_RESOURCE_TYPE_IO)
903                 return AE_OK;
904
905         /*
906          * The first address region returned is the data port, and
907          * the second address region returned is the status/command
908          * port.
909          */
910         if (ec->data_addr == 0)
911                 ec->data_addr = resource->data.io.minimum;
912         else if (ec->command_addr == 0)
913                 ec->command_addr = resource->data.io.minimum;
914         else
915                 return AE_CTRL_TERMINATE;
916
917         return AE_OK;
918 }
919
920 int __init acpi_boot_ec_enable(void)
921 {
922         if (!boot_ec || test_bit(EC_FLAGS_HANDLERS_INSTALLED, &boot_ec->flags))
923                 return 0;
924         if (!ec_install_handlers(boot_ec)) {
925                 first_ec = boot_ec;
926                 return 0;
927         }
928         return -EFAULT;
929 }
930
931 static const struct acpi_device_id ec_device_ids[] = {
932         {"PNP0C09", 0},
933         {"", 0},
934 };
935
936 /* Some BIOS do not survive early DSDT scan, skip it */
937 static int ec_skip_dsdt_scan(const struct dmi_system_id *id)
938 {
939         EC_FLAGS_SKIP_DSDT_SCAN = 1;
940         return 0;
941 }
942
943 /* ASUStek often supplies us with broken ECDT, validate it */
944 static int ec_validate_ecdt(const struct dmi_system_id *id)
945 {
946         EC_FLAGS_VALIDATE_ECDT = 1;
947         return 0;
948 }
949
950 /* MSI EC needs special treatment, enable it */
951 static int ec_flag_msi(const struct dmi_system_id *id)
952 {
953         printk(KERN_DEBUG PREFIX "Detected MSI hardware, enabling workarounds.\n");
954         EC_FLAGS_MSI = 1;
955         EC_FLAGS_VALIDATE_ECDT = 1;
956         return 0;
957 }
958
959 static struct dmi_system_id __initdata ec_dmi_table[] = {
960         {
961         ec_skip_dsdt_scan, "Compal JFL92", {
962         DMI_MATCH(DMI_BIOS_VENDOR, "COMPAL"),
963         DMI_MATCH(DMI_BOARD_NAME, "JFL92") }, NULL},
964         {
965         ec_flag_msi, "MSI hardware", {
966         DMI_MATCH(DMI_BIOS_VENDOR, "Micro-Star")}, NULL},
967         {
968         ec_flag_msi, "MSI hardware", {
969         DMI_MATCH(DMI_SYS_VENDOR, "Micro-Star")}, NULL},
970         {
971         ec_flag_msi, "MSI hardware", {
972         DMI_MATCH(DMI_CHASSIS_VENDOR, "MICRO-Star")}, NULL},
973         {
974         ec_validate_ecdt, "ASUS hardware", {
975         DMI_MATCH(DMI_BIOS_VENDOR, "ASUS") }, NULL},
976         {},
977 };
978
979
980 int __init acpi_ec_ecdt_probe(void)
981 {
982         acpi_status status;
983         struct acpi_ec *saved_ec = NULL;
984         struct acpi_table_ecdt *ecdt_ptr;
985
986         boot_ec = make_acpi_ec();
987         if (!boot_ec)
988                 return -ENOMEM;
989         /*
990          * Generate a boot ec context
991          */
992         dmi_check_system(ec_dmi_table);
993         status = acpi_get_table(ACPI_SIG_ECDT, 1,
994                                 (struct acpi_table_header **)&ecdt_ptr);
995         if (ACPI_SUCCESS(status)) {
996                 pr_info(PREFIX "EC description table is found, configuring boot EC\n");
997                 boot_ec->command_addr = ecdt_ptr->control.address;
998                 boot_ec->data_addr = ecdt_ptr->data.address;
999                 boot_ec->gpe = ecdt_ptr->gpe;
1000                 boot_ec->handle = ACPI_ROOT_OBJECT;
1001                 acpi_get_handle(ACPI_ROOT_OBJECT, ecdt_ptr->id, &boot_ec->handle);
1002                 /* Don't trust ECDT, which comes from ASUSTek */
1003                 if (!EC_FLAGS_VALIDATE_ECDT)
1004                         goto install;
1005                 saved_ec = kmalloc(sizeof(struct acpi_ec), GFP_KERNEL);
1006                 if (!saved_ec)
1007                         return -ENOMEM;
1008                 memcpy(saved_ec, boot_ec, sizeof(struct acpi_ec));
1009         /* fall through */
1010         }
1011
1012         if (EC_FLAGS_SKIP_DSDT_SCAN)
1013                 return -ENODEV;
1014
1015         /* This workaround is needed only on some broken machines,
1016          * which require early EC, but fail to provide ECDT */
1017         printk(KERN_DEBUG PREFIX "Look up EC in DSDT\n");
1018         status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device,
1019                                         boot_ec, NULL);
1020         /* Check that acpi_get_devices actually find something */
1021         if (ACPI_FAILURE(status) || !boot_ec->handle)
1022                 goto error;
1023         if (saved_ec) {
1024                 /* try to find good ECDT from ASUSTek */
1025                 if (saved_ec->command_addr != boot_ec->command_addr ||
1026                     saved_ec->data_addr != boot_ec->data_addr ||
1027                     saved_ec->gpe != boot_ec->gpe ||
1028                     saved_ec->handle != boot_ec->handle)
1029                         pr_info(PREFIX "ASUSTek keeps feeding us with broken "
1030                         "ECDT tables, which are very hard to workaround. "
1031                         "Trying to use DSDT EC info instead. Please send "
1032                         "output of acpidump to linux-acpi@vger.kernel.org\n");
1033                 kfree(saved_ec);
1034                 saved_ec = NULL;
1035         } else {
1036                 /* We really need to limit this workaround, the only ASUS,
1037                 * which needs it, has fake EC._INI method, so use it as flag.
1038                 * Keep boot_ec struct as it will be needed soon.
1039                 */
1040                 acpi_handle dummy;
1041                 if (!dmi_name_in_vendors("ASUS") ||
1042                     ACPI_FAILURE(acpi_get_handle(boot_ec->handle, "_INI",
1043                                                         &dummy)))
1044                         return -ENODEV;
1045         }
1046 install:
1047         if (!ec_install_handlers(boot_ec)) {
1048                 first_ec = boot_ec;
1049                 return 0;
1050         }
1051 error:
1052         kfree(boot_ec);
1053         boot_ec = NULL;
1054         return -ENODEV;
1055 }
1056
1057 static int acpi_ec_suspend(struct acpi_device *device, pm_message_t state)
1058 {
1059         struct acpi_ec *ec = acpi_driver_data(device);
1060         /* Stop using GPE */
1061         acpi_disable_gpe(NULL, ec->gpe);
1062         return 0;
1063 }
1064
1065 static int acpi_ec_resume(struct acpi_device *device)
1066 {
1067         struct acpi_ec *ec = acpi_driver_data(device);
1068         /* Enable use of GPE back */
1069         acpi_enable_gpe(NULL, ec->gpe);
1070         return 0;
1071 }
1072
1073 static struct acpi_driver acpi_ec_driver = {
1074         .name = "ec",
1075         .class = ACPI_EC_CLASS,
1076         .ids = ec_device_ids,
1077         .ops = {
1078                 .add = acpi_ec_add,
1079                 .remove = acpi_ec_remove,
1080                 .suspend = acpi_ec_suspend,
1081                 .resume = acpi_ec_resume,
1082                 },
1083 };
1084
1085 int __init acpi_ec_init(void)
1086 {
1087         int result = 0;
1088
1089         acpi_ec_dir = proc_mkdir(ACPI_EC_CLASS, acpi_root_dir);
1090         if (!acpi_ec_dir)
1091                 return -ENODEV;
1092
1093         /* Now register the driver for the EC */
1094         result = acpi_bus_register_driver(&acpi_ec_driver);
1095         if (result < 0) {
1096                 remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1097                 return -ENODEV;
1098         }
1099
1100         return result;
1101 }
1102
1103 /* EC driver currently not unloadable */
1104 #if 0
1105 static void __exit acpi_ec_exit(void)
1106 {
1107
1108         acpi_bus_unregister_driver(&acpi_ec_driver);
1109
1110         remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1111
1112         return;
1113 }
1114 #endif  /* 0 */