Merge branch 'ec' into release
[sfrench/cifs-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
46 #define ACPI_EC_CLASS                   "embedded_controller"
47 #define ACPI_EC_DEVICE_NAME             "Embedded Controller"
48 #define ACPI_EC_FILE_INFO               "info"
49
50 #define PREFIX                          "ACPI: EC: "
51
52 /* EC status register */
53 #define ACPI_EC_FLAG_OBF        0x01    /* Output buffer full */
54 #define ACPI_EC_FLAG_IBF        0x02    /* Input buffer full */
55 #define ACPI_EC_FLAG_BURST      0x10    /* burst mode */
56 #define ACPI_EC_FLAG_SCI        0x20    /* EC-SCI occurred */
57
58 /* EC commands */
59 enum ec_command {
60         ACPI_EC_COMMAND_READ = 0x80,
61         ACPI_EC_COMMAND_WRITE = 0x81,
62         ACPI_EC_BURST_ENABLE = 0x82,
63         ACPI_EC_BURST_DISABLE = 0x83,
64         ACPI_EC_COMMAND_QUERY = 0x84,
65 };
66
67 #define ACPI_EC_DELAY           500     /* Wait 500ms max. during EC ops */
68 #define ACPI_EC_UDELAY_GLK      1000    /* Wait 1ms max. to get global lock */
69 #define ACPI_EC_CDELAY          10      /* Wait 10us before polling EC */
70 #define ACPI_EC_MSI_UDELAY      550     /* Wait 550us for MSI EC */
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_STORM,             /* GPE storm detected */
78         EC_FLAGS_HANDLERS_INSTALLED     /* Handlers for GPE and
79                                          * OpReg are installed */
80 };
81
82 /* If we find an EC via the ECDT, we need to keep a ptr to its context */
83 /* External interfaces use first EC only, so remember */
84 typedef int (*acpi_ec_query_func) (void *data);
85
86 struct acpi_ec_query_handler {
87         struct list_head node;
88         acpi_ec_query_func func;
89         acpi_handle handle;
90         void *data;
91         u8 query_bit;
92 };
93
94 struct transaction {
95         const u8 *wdata;
96         u8 *rdata;
97         unsigned short irq_count;
98         u8 command;
99         u8 wi;
100         u8 ri;
101         u8 wlen;
102         u8 rlen;
103         bool done;
104 };
105
106 static struct acpi_ec {
107         acpi_handle handle;
108         unsigned long gpe;
109         unsigned long command_addr;
110         unsigned long data_addr;
111         unsigned long global_lock;
112         unsigned long flags;
113         struct mutex lock;
114         wait_queue_head_t wait;
115         struct list_head list;
116         struct transaction *curr;
117         spinlock_t curr_lock;
118 } *boot_ec, *first_ec;
119
120 static int EC_FLAGS_MSI; /* Out-of-spec MSI controller */
121
122 /* --------------------------------------------------------------------------
123                              Transaction Management
124    -------------------------------------------------------------------------- */
125
126 static inline u8 acpi_ec_read_status(struct acpi_ec *ec)
127 {
128         u8 x = inb(ec->command_addr);
129         pr_debug(PREFIX "---> status = 0x%2.2x\n", x);
130         return x;
131 }
132
133 static inline u8 acpi_ec_read_data(struct acpi_ec *ec)
134 {
135         u8 x = inb(ec->data_addr);
136         pr_debug(PREFIX "---> data = 0x%2.2x\n", x);
137         return x;
138 }
139
140 static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command)
141 {
142         pr_debug(PREFIX "<--- command = 0x%2.2x\n", command);
143         outb(command, ec->command_addr);
144 }
145
146 static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data)
147 {
148         pr_debug(PREFIX "<--- data = 0x%2.2x\n", data);
149         outb(data, ec->data_addr);
150 }
151
152 static int ec_transaction_done(struct acpi_ec *ec)
153 {
154         unsigned long flags;
155         int ret = 0;
156         spin_lock_irqsave(&ec->curr_lock, flags);
157         if (!ec->curr || ec->curr->done)
158                 ret = 1;
159         spin_unlock_irqrestore(&ec->curr_lock, flags);
160         return ret;
161 }
162
163 static void start_transaction(struct acpi_ec *ec)
164 {
165         ec->curr->irq_count = ec->curr->wi = ec->curr->ri = 0;
166         ec->curr->done = false;
167         acpi_ec_write_cmd(ec, ec->curr->command);
168 }
169
170 static void advance_transaction(struct acpi_ec *ec, u8 status)
171 {
172         unsigned long flags;
173         spin_lock_irqsave(&ec->curr_lock, flags);
174         if (!ec->curr)
175                 goto unlock;
176         if (ec->curr->wlen > ec->curr->wi) {
177                 if ((status & ACPI_EC_FLAG_IBF) == 0)
178                         acpi_ec_write_data(ec,
179                                 ec->curr->wdata[ec->curr->wi++]);
180                 else
181                         goto err;
182         } else if (ec->curr->rlen > ec->curr->ri) {
183                 if ((status & ACPI_EC_FLAG_OBF) == 1) {
184                         ec->curr->rdata[ec->curr->ri++] = acpi_ec_read_data(ec);
185                         if (ec->curr->rlen == ec->curr->ri)
186                                 ec->curr->done = true;
187                 } else
188                         goto err;
189         } else if (ec->curr->wlen == ec->curr->wi &&
190                    (status & ACPI_EC_FLAG_IBF) == 0)
191                 ec->curr->done = true;
192         goto unlock;
193 err:
194         /* false interrupt, state didn't change */
195         if (in_interrupt())
196                 ++ec->curr->irq_count;
197 unlock:
198         spin_unlock_irqrestore(&ec->curr_lock, flags);
199 }
200
201 static void acpi_ec_gpe_query(void *ec_cxt);
202
203 static int ec_check_sci(struct acpi_ec *ec, u8 state)
204 {
205         if (state & ACPI_EC_FLAG_SCI) {
206                 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags))
207                         return acpi_os_execute(OSL_EC_BURST_HANDLER,
208                                 acpi_ec_gpe_query, ec);
209         }
210         return 0;
211 }
212
213 static int ec_poll(struct acpi_ec *ec)
214 {
215         unsigned long flags;
216         int repeat = 2; /* number of command restarts */
217         while (repeat--) {
218                 unsigned long delay = jiffies +
219                         msecs_to_jiffies(ACPI_EC_DELAY);
220                 do {
221                         /* don't sleep with disabled interrupts */
222                         if (EC_FLAGS_MSI || irqs_disabled()) {
223                                 udelay(ACPI_EC_MSI_UDELAY);
224                                 if (ec_transaction_done(ec))
225                                         return 0;
226                         } else {
227                                 if (wait_event_timeout(ec->wait,
228                                                 ec_transaction_done(ec),
229                                                 msecs_to_jiffies(1)))
230                                         return 0;
231                         }
232                         advance_transaction(ec, acpi_ec_read_status(ec));
233                 } while (time_before(jiffies, delay));
234                 if (!ec->curr->irq_count ||
235                     (acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF))
236                         break;
237                 /* try restart command if we get any false interrupts */
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         pr_debug(PREFIX "transaction start\n");
252         /* disable GPE during transaction if storm is detected */
253         if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
254                 acpi_disable_gpe(NULL, ec->gpe);
255         }
256         if (EC_FLAGS_MSI)
257                 udelay(ACPI_EC_MSI_UDELAY);
258         /* start transaction */
259         spin_lock_irqsave(&ec->curr_lock, tmp);
260         /* following two actions should be kept atomic */
261         ec->curr = t;
262         start_transaction(ec);
263         if (ec->curr->command == ACPI_EC_COMMAND_QUERY)
264                 clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
265         spin_unlock_irqrestore(&ec->curr_lock, tmp);
266         ret = ec_poll(ec);
267         pr_debug(PREFIX "transaction end\n");
268         spin_lock_irqsave(&ec->curr_lock, tmp);
269         ec->curr = NULL;
270         spin_unlock_irqrestore(&ec->curr_lock, tmp);
271         if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
272                 /* check if we received SCI during transaction */
273                 ec_check_sci(ec, acpi_ec_read_status(ec));
274                 /* it is safe to enable GPE outside of transaction */
275                 acpi_enable_gpe(NULL, ec->gpe);
276         } else if (t->irq_count > ACPI_EC_STORM_THRESHOLD) {
277                 pr_info(PREFIX "GPE storm detected, "
278                         "transactions will use polling mode\n");
279                 set_bit(EC_FLAGS_GPE_STORM, &ec->flags);
280         }
281         return ret;
282 }
283
284 static int ec_check_ibf0(struct acpi_ec *ec)
285 {
286         u8 status = acpi_ec_read_status(ec);
287         return (status & ACPI_EC_FLAG_IBF) == 0;
288 }
289
290 static int ec_wait_ibf0(struct acpi_ec *ec)
291 {
292         unsigned long delay = jiffies + msecs_to_jiffies(ACPI_EC_DELAY);
293         /* interrupt wait manually if GPE mode is not active */
294         while (time_before(jiffies, delay))
295                 if (wait_event_timeout(ec->wait, ec_check_ibf0(ec),
296                                         msecs_to_jiffies(1)))
297                         return 0;
298         return -ETIME;
299 }
300
301 static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t)
302 {
303         int status;
304         u32 glk;
305         if (!ec || (!t) || (t->wlen && !t->wdata) || (t->rlen && !t->rdata))
306                 return -EINVAL;
307         if (t->rdata)
308                 memset(t->rdata, 0, t->rlen);
309         mutex_lock(&ec->lock);
310         if (ec->global_lock) {
311                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
312                 if (ACPI_FAILURE(status)) {
313                         status = -ENODEV;
314                         goto unlock;
315                 }
316         }
317         if (ec_wait_ibf0(ec)) {
318                 pr_err(PREFIX "input buffer is not empty, "
319                                 "aborting transaction\n");
320                 status = -ETIME;
321                 goto end;
322         }
323         status = acpi_ec_transaction_unlocked(ec, t);
324 end:
325         if (ec->global_lock)
326                 acpi_release_global_lock(glk);
327 unlock:
328         mutex_unlock(&ec->lock);
329         return status;
330 }
331
332 static int acpi_ec_burst_enable(struct acpi_ec *ec)
333 {
334         u8 d;
335         struct transaction t = {.command = ACPI_EC_BURST_ENABLE,
336                                 .wdata = NULL, .rdata = &d,
337                                 .wlen = 0, .rlen = 1};
338
339         return acpi_ec_transaction(ec, &t);
340 }
341
342 static int acpi_ec_burst_disable(struct acpi_ec *ec)
343 {
344         struct transaction t = {.command = ACPI_EC_BURST_DISABLE,
345                                 .wdata = NULL, .rdata = NULL,
346                                 .wlen = 0, .rlen = 0};
347
348         return (acpi_ec_read_status(ec) & ACPI_EC_FLAG_BURST) ?
349                                 acpi_ec_transaction(ec, &t) : 0;
350 }
351
352 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 * data)
353 {
354         int result;
355         u8 d;
356         struct transaction t = {.command = ACPI_EC_COMMAND_READ,
357                                 .wdata = &address, .rdata = &d,
358                                 .wlen = 1, .rlen = 1};
359
360         result = acpi_ec_transaction(ec, &t);
361         *data = d;
362         return result;
363 }
364
365 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
366 {
367         u8 wdata[2] = { address, data };
368         struct transaction t = {.command = ACPI_EC_COMMAND_WRITE,
369                                 .wdata = wdata, .rdata = NULL,
370                                 .wlen = 2, .rlen = 0};
371
372         return acpi_ec_transaction(ec, &t);
373 }
374
375 /*
376  * Externally callable EC access functions. For now, assume 1 EC only
377  */
378 int ec_burst_enable(void)
379 {
380         if (!first_ec)
381                 return -ENODEV;
382         return acpi_ec_burst_enable(first_ec);
383 }
384
385 EXPORT_SYMBOL(ec_burst_enable);
386
387 int ec_burst_disable(void)
388 {
389         if (!first_ec)
390                 return -ENODEV;
391         return acpi_ec_burst_disable(first_ec);
392 }
393
394 EXPORT_SYMBOL(ec_burst_disable);
395
396 int ec_read(u8 addr, u8 * val)
397 {
398         int err;
399         u8 temp_data;
400
401         if (!first_ec)
402                 return -ENODEV;
403
404         err = acpi_ec_read(first_ec, addr, &temp_data);
405
406         if (!err) {
407                 *val = temp_data;
408                 return 0;
409         } else
410                 return err;
411 }
412
413 EXPORT_SYMBOL(ec_read);
414
415 int ec_write(u8 addr, u8 val)
416 {
417         int err;
418
419         if (!first_ec)
420                 return -ENODEV;
421
422         err = acpi_ec_write(first_ec, addr, val);
423
424         return err;
425 }
426
427 EXPORT_SYMBOL(ec_write);
428
429 int ec_transaction(u8 command,
430                    const u8 * wdata, unsigned wdata_len,
431                    u8 * rdata, unsigned rdata_len,
432                    int force_poll)
433 {
434         struct transaction t = {.command = command,
435                                 .wdata = wdata, .rdata = rdata,
436                                 .wlen = wdata_len, .rlen = rdata_len};
437         if (!first_ec)
438                 return -ENODEV;
439
440         return acpi_ec_transaction(first_ec, &t);
441 }
442
443 EXPORT_SYMBOL(ec_transaction);
444
445 static int acpi_ec_query(struct acpi_ec *ec, u8 * data)
446 {
447         int result;
448         u8 d;
449         struct transaction t = {.command = ACPI_EC_COMMAND_QUERY,
450                                 .wdata = NULL, .rdata = &d,
451                                 .wlen = 0, .rlen = 1};
452         if (!ec || !data)
453                 return -EINVAL;
454
455         /*
456          * Query the EC to find out which _Qxx method we need to evaluate.
457          * Note that successful completion of the query causes the ACPI_EC_SCI
458          * bit to be cleared (and thus clearing the interrupt source).
459          */
460
461         result = acpi_ec_transaction(ec, &t);
462         if (result)
463                 return result;
464
465         if (!d)
466                 return -ENODATA;
467
468         *data = d;
469         return 0;
470 }
471
472 /* --------------------------------------------------------------------------
473                                 Event Management
474    -------------------------------------------------------------------------- */
475 int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
476                               acpi_handle handle, acpi_ec_query_func func,
477                               void *data)
478 {
479         struct acpi_ec_query_handler *handler =
480             kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL);
481         if (!handler)
482                 return -ENOMEM;
483
484         handler->query_bit = query_bit;
485         handler->handle = handle;
486         handler->func = func;
487         handler->data = data;
488         mutex_lock(&ec->lock);
489         list_add(&handler->node, &ec->list);
490         mutex_unlock(&ec->lock);
491         return 0;
492 }
493
494 EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler);
495
496 void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit)
497 {
498         struct acpi_ec_query_handler *handler, *tmp;
499         mutex_lock(&ec->lock);
500         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
501                 if (query_bit == handler->query_bit) {
502                         list_del(&handler->node);
503                         kfree(handler);
504                 }
505         }
506         mutex_unlock(&ec->lock);
507 }
508
509 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler);
510
511 static void acpi_ec_gpe_query(void *ec_cxt)
512 {
513         struct acpi_ec *ec = ec_cxt;
514         u8 value = 0;
515         struct acpi_ec_query_handler *handler, copy;
516
517         if (!ec || acpi_ec_query(ec, &value))
518                 return;
519         mutex_lock(&ec->lock);
520         list_for_each_entry(handler, &ec->list, node) {
521                 if (value == handler->query_bit) {
522                         /* have custom handler for this bit */
523                         memcpy(&copy, handler, sizeof(copy));
524                         mutex_unlock(&ec->lock);
525                         if (copy.func) {
526                                 copy.func(copy.data);
527                         } else if (copy.handle) {
528                                 acpi_evaluate_object(copy.handle, NULL, NULL, NULL);
529                         }
530                         return;
531                 }
532         }
533         mutex_unlock(&ec->lock);
534 }
535
536 static u32 acpi_ec_gpe_handler(void *data)
537 {
538         struct acpi_ec *ec = data;
539         u8 status;
540
541         pr_debug(PREFIX "~~~> interrupt\n");
542         status = acpi_ec_read_status(ec);
543
544         advance_transaction(ec, status);
545         if (ec_transaction_done(ec) && (status & ACPI_EC_FLAG_IBF) == 0)
546                 wake_up(&ec->wait);
547         ec_check_sci(ec, status);
548         return ACPI_INTERRUPT_HANDLED;
549 }
550
551 /* --------------------------------------------------------------------------
552                              Address Space Management
553    -------------------------------------------------------------------------- */
554
555 static acpi_status
556 acpi_ec_space_handler(u32 function, acpi_physical_address address,
557                       u32 bits, acpi_integer *value,
558                       void *handler_context, void *region_context)
559 {
560         struct acpi_ec *ec = handler_context;
561         int result = 0, i;
562         u8 temp = 0;
563
564         if ((address > 0xFF) || !value || !handler_context)
565                 return AE_BAD_PARAMETER;
566
567         if (function != ACPI_READ && function != ACPI_WRITE)
568                 return AE_BAD_PARAMETER;
569
570         if (bits != 8 && acpi_strict)
571                 return AE_BAD_PARAMETER;
572
573         if (EC_FLAGS_MSI)
574                 acpi_ec_burst_enable(ec);
575
576         if (function == ACPI_READ) {
577                 result = acpi_ec_read(ec, address, &temp);
578                 *value = temp;
579         } else {
580                 temp = 0xff & (*value);
581                 result = acpi_ec_write(ec, address, temp);
582         }
583
584         for (i = 8; unlikely(bits - i > 0); i += 8) {
585                 ++address;
586                 if (function == ACPI_READ) {
587                         result = acpi_ec_read(ec, address, &temp);
588                         (*value) |= ((acpi_integer)temp) << i;
589                 } else {
590                         temp = 0xff & ((*value) >> i);
591                         result = acpi_ec_write(ec, address, temp);
592                 }
593         }
594
595         if (EC_FLAGS_MSI)
596                 acpi_ec_burst_disable(ec);
597
598         switch (result) {
599         case -EINVAL:
600                 return AE_BAD_PARAMETER;
601                 break;
602         case -ENODEV:
603                 return AE_NOT_FOUND;
604                 break;
605         case -ETIME:
606                 return AE_TIME;
607                 break;
608         default:
609                 return AE_OK;
610         }
611 }
612
613 /* --------------------------------------------------------------------------
614                               FS Interface (/proc)
615    -------------------------------------------------------------------------- */
616
617 static struct proc_dir_entry *acpi_ec_dir;
618
619 static int acpi_ec_read_info(struct seq_file *seq, void *offset)
620 {
621         struct acpi_ec *ec = seq->private;
622
623         if (!ec)
624                 goto end;
625
626         seq_printf(seq, "gpe:\t\t\t0x%02x\n", (u32) ec->gpe);
627         seq_printf(seq, "ports:\t\t\t0x%02x, 0x%02x\n",
628                    (unsigned)ec->command_addr, (unsigned)ec->data_addr);
629         seq_printf(seq, "use global lock:\t%s\n",
630                    ec->global_lock ? "yes" : "no");
631       end:
632         return 0;
633 }
634
635 static int acpi_ec_info_open_fs(struct inode *inode, struct file *file)
636 {
637         return single_open(file, acpi_ec_read_info, PDE(inode)->data);
638 }
639
640 static const struct file_operations acpi_ec_info_ops = {
641         .open = acpi_ec_info_open_fs,
642         .read = seq_read,
643         .llseek = seq_lseek,
644         .release = single_release,
645         .owner = THIS_MODULE,
646 };
647
648 static int acpi_ec_add_fs(struct acpi_device *device)
649 {
650         struct proc_dir_entry *entry = NULL;
651
652         if (!acpi_device_dir(device)) {
653                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
654                                                      acpi_ec_dir);
655                 if (!acpi_device_dir(device))
656                         return -ENODEV;
657         }
658
659         entry = proc_create_data(ACPI_EC_FILE_INFO, S_IRUGO,
660                                  acpi_device_dir(device),
661                                  &acpi_ec_info_ops, acpi_driver_data(device));
662         if (!entry)
663                 return -ENODEV;
664         return 0;
665 }
666
667 static int acpi_ec_remove_fs(struct acpi_device *device)
668 {
669
670         if (acpi_device_dir(device)) {
671                 remove_proc_entry(ACPI_EC_FILE_INFO, acpi_device_dir(device));
672                 remove_proc_entry(acpi_device_bid(device), acpi_ec_dir);
673                 acpi_device_dir(device) = NULL;
674         }
675
676         return 0;
677 }
678
679 /* --------------------------------------------------------------------------
680                                Driver Interface
681    -------------------------------------------------------------------------- */
682 static acpi_status
683 ec_parse_io_ports(struct acpi_resource *resource, void *context);
684
685 static struct acpi_ec *make_acpi_ec(void)
686 {
687         struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
688         if (!ec)
689                 return NULL;
690         ec->flags = 1 << EC_FLAGS_QUERY_PENDING;
691         mutex_init(&ec->lock);
692         init_waitqueue_head(&ec->wait);
693         INIT_LIST_HEAD(&ec->list);
694         spin_lock_init(&ec->curr_lock);
695         return ec;
696 }
697
698 static acpi_status
699 acpi_ec_register_query_methods(acpi_handle handle, u32 level,
700                                void *context, void **return_value)
701 {
702         char node_name[5];
703         struct acpi_buffer buffer = { sizeof(node_name), node_name };
704         struct acpi_ec *ec = context;
705         int value = 0;
706         acpi_status status;
707
708         status = acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
709
710         if (ACPI_SUCCESS(status) && sscanf(node_name, "_Q%x", &value) == 1) {
711                 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL);
712         }
713         return AE_OK;
714 }
715
716 static acpi_status
717 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
718 {
719         acpi_status status;
720         unsigned long long tmp = 0;
721
722         struct acpi_ec *ec = context;
723
724         /* clear addr values, ec_parse_io_ports depend on it */
725         ec->command_addr = ec->data_addr = 0;
726
727         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
728                                      ec_parse_io_ports, ec);
729         if (ACPI_FAILURE(status))
730                 return status;
731
732         /* Get GPE bit assignment (EC events). */
733         /* TODO: Add support for _GPE returning a package */
734         status = acpi_evaluate_integer(handle, "_GPE", NULL, &tmp);
735         if (ACPI_FAILURE(status))
736                 return status;
737         ec->gpe = tmp;
738         /* Use the global lock for all EC transactions? */
739         tmp = 0;
740         acpi_evaluate_integer(handle, "_GLK", NULL, &tmp);
741         ec->global_lock = tmp;
742         ec->handle = handle;
743         return AE_CTRL_TERMINATE;
744 }
745
746 static int ec_install_handlers(struct acpi_ec *ec)
747 {
748         acpi_status status;
749         if (test_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags))
750                 return 0;
751         status = acpi_install_gpe_handler(NULL, ec->gpe,
752                                   ACPI_GPE_EDGE_TRIGGERED,
753                                   &acpi_ec_gpe_handler, ec);
754         if (ACPI_FAILURE(status))
755                 return -ENODEV;
756         acpi_set_gpe_type(NULL, ec->gpe, ACPI_GPE_TYPE_RUNTIME);
757         acpi_enable_gpe(NULL, ec->gpe);
758         status = acpi_install_address_space_handler(ec->handle,
759                                                     ACPI_ADR_SPACE_EC,
760                                                     &acpi_ec_space_handler,
761                                                     NULL, ec);
762         if (ACPI_FAILURE(status)) {
763                 if (status == AE_NOT_FOUND) {
764                         /*
765                          * Maybe OS fails in evaluating the _REG object.
766                          * The AE_NOT_FOUND error will be ignored and OS
767                          * continue to initialize EC.
768                          */
769                         printk(KERN_ERR "Fail in evaluating the _REG object"
770                                 " of EC device. Broken bios is suspected.\n");
771                 } else {
772                         acpi_remove_gpe_handler(NULL, ec->gpe,
773                                 &acpi_ec_gpe_handler);
774                         return -ENODEV;
775                 }
776         }
777
778         set_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
779         return 0;
780 }
781
782 static void ec_remove_handlers(struct acpi_ec *ec)
783 {
784         if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle,
785                                 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler)))
786                 pr_err(PREFIX "failed to remove space handler\n");
787         if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe,
788                                 &acpi_ec_gpe_handler)))
789                 pr_err(PREFIX "failed to remove gpe handler\n");
790         clear_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
791 }
792
793 static int acpi_ec_add(struct acpi_device *device)
794 {
795         struct acpi_ec *ec = NULL;
796         int ret;
797
798         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
799         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
800
801         /* Check for boot EC */
802         if (boot_ec &&
803             (boot_ec->handle == device->handle ||
804              boot_ec->handle == ACPI_ROOT_OBJECT)) {
805                 ec = boot_ec;
806                 boot_ec = NULL;
807         } else {
808                 ec = make_acpi_ec();
809                 if (!ec)
810                         return -ENOMEM;
811         }
812         if (ec_parse_device(device->handle, 0, ec, NULL) !=
813                 AE_CTRL_TERMINATE) {
814                         kfree(ec);
815                         return -EINVAL;
816         }
817
818         ec->handle = device->handle;
819
820         /* Find and register all query methods */
821         acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1,
822                             acpi_ec_register_query_methods, ec, NULL);
823
824         if (!first_ec)
825                 first_ec = ec;
826         device->driver_data = ec;
827         acpi_ec_add_fs(device);
828         pr_info(PREFIX "GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n",
829                           ec->gpe, ec->command_addr, ec->data_addr);
830
831         ret = ec_install_handlers(ec);
832
833         /* EC is fully operational, allow queries */
834         clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
835         return ret;
836 }
837
838 static int acpi_ec_remove(struct acpi_device *device, int type)
839 {
840         struct acpi_ec *ec;
841         struct acpi_ec_query_handler *handler, *tmp;
842
843         if (!device)
844                 return -EINVAL;
845
846         ec = acpi_driver_data(device);
847         ec_remove_handlers(ec);
848         mutex_lock(&ec->lock);
849         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
850                 list_del(&handler->node);
851                 kfree(handler);
852         }
853         mutex_unlock(&ec->lock);
854         acpi_ec_remove_fs(device);
855         device->driver_data = NULL;
856         if (ec == first_ec)
857                 first_ec = NULL;
858         kfree(ec);
859         return 0;
860 }
861
862 static acpi_status
863 ec_parse_io_ports(struct acpi_resource *resource, void *context)
864 {
865         struct acpi_ec *ec = context;
866
867         if (resource->type != ACPI_RESOURCE_TYPE_IO)
868                 return AE_OK;
869
870         /*
871          * The first address region returned is the data port, and
872          * the second address region returned is the status/command
873          * port.
874          */
875         if (ec->data_addr == 0)
876                 ec->data_addr = resource->data.io.minimum;
877         else if (ec->command_addr == 0)
878                 ec->command_addr = resource->data.io.minimum;
879         else
880                 return AE_CTRL_TERMINATE;
881
882         return AE_OK;
883 }
884
885 int __init acpi_boot_ec_enable(void)
886 {
887         if (!boot_ec || test_bit(EC_FLAGS_HANDLERS_INSTALLED, &boot_ec->flags))
888                 return 0;
889         if (!ec_install_handlers(boot_ec)) {
890                 first_ec = boot_ec;
891                 return 0;
892         }
893         return -EFAULT;
894 }
895
896 static const struct acpi_device_id ec_device_ids[] = {
897         {"PNP0C09", 0},
898         {"", 0},
899 };
900
901 int __init acpi_ec_ecdt_probe(void)
902 {
903         acpi_status status;
904         struct acpi_ec *saved_ec = NULL;
905         struct acpi_table_ecdt *ecdt_ptr;
906
907         boot_ec = make_acpi_ec();
908         if (!boot_ec)
909                 return -ENOMEM;
910         /*
911          * Generate a boot ec context
912          */
913         if (dmi_name_in_vendors("Micro-Star") ||
914             dmi_name_in_vendors("Notebook")) {
915                 pr_info(PREFIX "Enabling special treatment for EC from MSI.\n");
916                 EC_FLAGS_MSI = 1;
917         }
918         status = acpi_get_table(ACPI_SIG_ECDT, 1,
919                                 (struct acpi_table_header **)&ecdt_ptr);
920         if (ACPI_SUCCESS(status)) {
921                 pr_info(PREFIX "EC description table is found, configuring boot EC\n");
922                 boot_ec->command_addr = ecdt_ptr->control.address;
923                 boot_ec->data_addr = ecdt_ptr->data.address;
924                 boot_ec->gpe = ecdt_ptr->gpe;
925                 boot_ec->handle = ACPI_ROOT_OBJECT;
926                 acpi_get_handle(ACPI_ROOT_OBJECT, ecdt_ptr->id, &boot_ec->handle);
927                 /* Don't trust ECDT, which comes from ASUSTek */
928                 if (!dmi_name_in_vendors("ASUS") && EC_FLAGS_MSI == 0)
929                         goto install;
930                 saved_ec = kmalloc(sizeof(struct acpi_ec), GFP_KERNEL);
931                 if (!saved_ec)
932                         return -ENOMEM;
933                 memcpy(saved_ec, boot_ec, sizeof(struct acpi_ec));
934         /* fall through */
935         }
936         /* This workaround is needed only on some broken machines,
937          * which require early EC, but fail to provide ECDT */
938         printk(KERN_DEBUG PREFIX "Look up EC in DSDT\n");
939         status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device,
940                                         boot_ec, NULL);
941         /* Check that acpi_get_devices actually find something */
942         if (ACPI_FAILURE(status) || !boot_ec->handle)
943                 goto error;
944         if (saved_ec) {
945                 /* try to find good ECDT from ASUSTek */
946                 if (saved_ec->command_addr != boot_ec->command_addr ||
947                     saved_ec->data_addr != boot_ec->data_addr ||
948                     saved_ec->gpe != boot_ec->gpe ||
949                     saved_ec->handle != boot_ec->handle)
950                         pr_info(PREFIX "ASUSTek keeps feeding us with broken "
951                         "ECDT tables, which are very hard to workaround. "
952                         "Trying to use DSDT EC info instead. Please send "
953                         "output of acpidump to linux-acpi@vger.kernel.org\n");
954                 kfree(saved_ec);
955                 saved_ec = NULL;
956         } else {
957                 /* We really need to limit this workaround, the only ASUS,
958                 * which needs it, has fake EC._INI method, so use it as flag.
959                 * Keep boot_ec struct as it will be needed soon.
960                 */
961                 acpi_handle dummy;
962                 if (!dmi_name_in_vendors("ASUS") ||
963                     ACPI_FAILURE(acpi_get_handle(boot_ec->handle, "_INI",
964                                                         &dummy)))
965                         return -ENODEV;
966         }
967 install:
968         if (!ec_install_handlers(boot_ec)) {
969                 first_ec = boot_ec;
970                 return 0;
971         }
972 error:
973         kfree(boot_ec);
974         boot_ec = NULL;
975         return -ENODEV;
976 }
977
978 static int acpi_ec_suspend(struct acpi_device *device, pm_message_t state)
979 {
980         struct acpi_ec *ec = acpi_driver_data(device);
981         /* Stop using GPE */
982         acpi_disable_gpe(NULL, ec->gpe);
983         return 0;
984 }
985
986 static int acpi_ec_resume(struct acpi_device *device)
987 {
988         struct acpi_ec *ec = acpi_driver_data(device);
989         /* Enable use of GPE back */
990         acpi_enable_gpe(NULL, ec->gpe);
991         return 0;
992 }
993
994 static struct acpi_driver acpi_ec_driver = {
995         .name = "ec",
996         .class = ACPI_EC_CLASS,
997         .ids = ec_device_ids,
998         .ops = {
999                 .add = acpi_ec_add,
1000                 .remove = acpi_ec_remove,
1001                 .suspend = acpi_ec_suspend,
1002                 .resume = acpi_ec_resume,
1003                 },
1004 };
1005
1006 int __init acpi_ec_init(void)
1007 {
1008         int result = 0;
1009
1010         acpi_ec_dir = proc_mkdir(ACPI_EC_CLASS, acpi_root_dir);
1011         if (!acpi_ec_dir)
1012                 return -ENODEV;
1013
1014         /* Now register the driver for the EC */
1015         result = acpi_bus_register_driver(&acpi_ec_driver);
1016         if (result < 0) {
1017                 remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1018                 return -ENODEV;
1019         }
1020
1021         return result;
1022 }
1023
1024 /* EC driver currently not unloadable */
1025 #if 0
1026 static void __exit acpi_ec_exit(void)
1027 {
1028
1029         acpi_bus_unregister_driver(&acpi_ec_driver);
1030
1031         remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1032
1033         return;
1034 }
1035 #endif  /* 0 */