Merge branch 'topic/aoa' into to-push
[linux-2.6] / 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 <acpi/actypes.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 #undef PREFIX
52 #define PREFIX                          "ACPI: EC: "
53
54 /* EC status register */
55 #define ACPI_EC_FLAG_OBF        0x01    /* Output buffer full */
56 #define ACPI_EC_FLAG_IBF        0x02    /* Input buffer full */
57 #define ACPI_EC_FLAG_BURST      0x10    /* burst mode */
58 #define ACPI_EC_FLAG_SCI        0x20    /* EC-SCI occurred */
59
60 /* EC commands */
61 enum ec_command {
62         ACPI_EC_COMMAND_READ = 0x80,
63         ACPI_EC_COMMAND_WRITE = 0x81,
64         ACPI_EC_BURST_ENABLE = 0x82,
65         ACPI_EC_BURST_DISABLE = 0x83,
66         ACPI_EC_COMMAND_QUERY = 0x84,
67 };
68
69 #define ACPI_EC_DELAY           500     /* Wait 500ms max. during EC ops */
70 #define ACPI_EC_UDELAY_GLK      1000    /* Wait 1ms max. to get global lock */
71 #define ACPI_EC_UDELAY          100     /* Wait 100us before polling EC again */
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_MODE,              /* Expect GPE to be sent
79                                          * for status change */
80         EC_FLAGS_NO_GPE,                /* Don't use GPE mode */
81         EC_FLAGS_GPE_STORM,             /* GPE storm detected */
82         EC_FLAGS_HANDLERS_INSTALLED     /* Handlers for GPE and
83                                          * OpReg are installed */
84 };
85
86 /* If we find an EC via the ECDT, we need to keep a ptr to its context */
87 /* External interfaces use first EC only, so remember */
88 typedef int (*acpi_ec_query_func) (void *data);
89
90 struct acpi_ec_query_handler {
91         struct list_head node;
92         acpi_ec_query_func func;
93         acpi_handle handle;
94         void *data;
95         u8 query_bit;
96 };
97
98 struct transaction {
99         const u8 *wdata;
100         u8 *rdata;
101         unsigned short irq_count;
102         u8 command;
103         u8 wi;
104         u8 ri;
105         u8 wlen;
106         u8 rlen;
107         bool done;
108 };
109
110 static struct acpi_ec {
111         acpi_handle handle;
112         unsigned long gpe;
113         unsigned long command_addr;
114         unsigned long data_addr;
115         unsigned long global_lock;
116         unsigned long flags;
117         struct mutex lock;
118         wait_queue_head_t wait;
119         struct list_head list;
120         struct transaction *curr;
121         spinlock_t curr_lock;
122 } *boot_ec, *first_ec;
123
124 /* 
125  * Some Asus system have exchanged ECDT data/command IO addresses.
126  */
127 static int print_ecdt_error(const struct dmi_system_id *id)
128 {
129         printk(KERN_NOTICE PREFIX "%s detected - "
130                 "ECDT has exchanged control/data I/O address\n",
131                 id->ident);
132         return 0;
133 }
134
135 static struct dmi_system_id __cpuinitdata ec_dmi_table[] = {
136         {
137         print_ecdt_error, "Asus L4R", {
138         DMI_MATCH(DMI_BIOS_VERSION, "1008.006"),
139         DMI_MATCH(DMI_PRODUCT_NAME, "L4R"),
140         DMI_MATCH(DMI_BOARD_NAME, "L4R") }, NULL},
141         {
142         print_ecdt_error, "Asus M6R", {
143         DMI_MATCH(DMI_BIOS_VERSION, "0207"),
144         DMI_MATCH(DMI_PRODUCT_NAME, "M6R"),
145         DMI_MATCH(DMI_BOARD_NAME, "M6R") }, NULL},
146         {},
147 };
148
149 /* --------------------------------------------------------------------------
150                              Transaction Management
151    -------------------------------------------------------------------------- */
152
153 static inline u8 acpi_ec_read_status(struct acpi_ec *ec)
154 {
155         u8 x = inb(ec->command_addr);
156         pr_debug(PREFIX "---> status = 0x%2.2x\n", x);
157         return x;
158 }
159
160 static inline u8 acpi_ec_read_data(struct acpi_ec *ec)
161 {
162         u8 x = inb(ec->data_addr);
163         pr_debug(PREFIX "---> data = 0x%2.2x\n", x);
164         return x;
165 }
166
167 static inline void acpi_ec_write_cmd(struct acpi_ec *ec, u8 command)
168 {
169         pr_debug(PREFIX "<--- command = 0x%2.2x\n", command);
170         outb(command, ec->command_addr);
171 }
172
173 static inline void acpi_ec_write_data(struct acpi_ec *ec, u8 data)
174 {
175         pr_debug(PREFIX "<--- data = 0x%2.2x\n", data);
176         outb(data, ec->data_addr);
177 }
178
179 static int ec_transaction_done(struct acpi_ec *ec)
180 {
181         unsigned long flags;
182         int ret = 0;
183         spin_lock_irqsave(&ec->curr_lock, flags);
184         if (!ec->curr || ec->curr->done)
185                 ret = 1;
186         spin_unlock_irqrestore(&ec->curr_lock, flags);
187         return ret;
188 }
189
190 static void start_transaction(struct acpi_ec *ec)
191 {
192         ec->curr->irq_count = ec->curr->wi = ec->curr->ri = 0;
193         ec->curr->done = false;
194         acpi_ec_write_cmd(ec, ec->curr->command);
195 }
196
197 static void gpe_transaction(struct acpi_ec *ec, u8 status)
198 {
199         unsigned long flags;
200         spin_lock_irqsave(&ec->curr_lock, flags);
201         if (!ec->curr)
202                 goto unlock;
203         if (ec->curr->wlen > ec->curr->wi) {
204                 if ((status & ACPI_EC_FLAG_IBF) == 0)
205                         acpi_ec_write_data(ec,
206                                 ec->curr->wdata[ec->curr->wi++]);
207                 else
208                         goto err;
209         } else if (ec->curr->rlen > ec->curr->ri) {
210                 if ((status & ACPI_EC_FLAG_OBF) == 1) {
211                         ec->curr->rdata[ec->curr->ri++] = acpi_ec_read_data(ec);
212                         if (ec->curr->rlen == ec->curr->ri)
213                                 ec->curr->done = true;
214                 } else
215                         goto err;
216         } else if (ec->curr->wlen == ec->curr->wi &&
217                    (status & ACPI_EC_FLAG_IBF) == 0)
218                 ec->curr->done = true;
219         goto unlock;
220 err:
221         /* false interrupt, state didn't change */
222         if (in_interrupt())
223                 ++ec->curr->irq_count;
224 unlock:
225         spin_unlock_irqrestore(&ec->curr_lock, flags);
226 }
227
228 static int acpi_ec_wait(struct acpi_ec *ec)
229 {
230         if (wait_event_timeout(ec->wait, ec_transaction_done(ec),
231                                msecs_to_jiffies(ACPI_EC_DELAY)))
232                 return 0;
233         /* try restart command if we get any false interrupts */
234         if (ec->curr->irq_count &&
235             (acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF) == 0) {
236                 pr_debug(PREFIX "controller reset, restart transaction\n");
237                 start_transaction(ec);
238                 if (wait_event_timeout(ec->wait, ec_transaction_done(ec),
239                                         msecs_to_jiffies(ACPI_EC_DELAY)))
240                         return 0;
241         }
242         /* missing GPEs, switch back to poll mode */
243         if (printk_ratelimit())
244                 pr_info(PREFIX "missing confirmations, "
245                                 "switch off interrupt mode.\n");
246         set_bit(EC_FLAGS_NO_GPE, &ec->flags);
247         clear_bit(EC_FLAGS_GPE_MODE, &ec->flags);
248         return 1;
249 }
250
251 static void acpi_ec_gpe_query(void *ec_cxt);
252
253 static int ec_check_sci(struct acpi_ec *ec, u8 state)
254 {
255         if (state & ACPI_EC_FLAG_SCI) {
256                 if (!test_and_set_bit(EC_FLAGS_QUERY_PENDING, &ec->flags))
257                         return acpi_os_execute(OSL_EC_BURST_HANDLER,
258                                 acpi_ec_gpe_query, ec);
259         }
260         return 0;
261 }
262
263 static int ec_poll(struct acpi_ec *ec)
264 {
265         unsigned long delay = jiffies + msecs_to_jiffies(ACPI_EC_DELAY);
266         udelay(ACPI_EC_UDELAY);
267         while (time_before(jiffies, delay)) {
268                 gpe_transaction(ec, acpi_ec_read_status(ec));
269                 udelay(ACPI_EC_UDELAY);
270                 if (ec_transaction_done(ec))
271                         return 0;
272         }
273         return -ETIME;
274 }
275
276 static int acpi_ec_transaction_unlocked(struct acpi_ec *ec,
277                                         struct transaction *t,
278                                         int force_poll)
279 {
280         unsigned long tmp;
281         int ret = 0;
282         pr_debug(PREFIX "transaction start\n");
283         /* disable GPE during transaction if storm is detected */
284         if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
285                 clear_bit(EC_FLAGS_GPE_MODE, &ec->flags);
286                 acpi_disable_gpe(NULL, ec->gpe);
287         }
288         /* start transaction */
289         spin_lock_irqsave(&ec->curr_lock, tmp);
290         /* following two actions should be kept atomic */
291         ec->curr = t;
292         start_transaction(ec);
293         if (ec->curr->command == ACPI_EC_COMMAND_QUERY)
294                 clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
295         spin_unlock_irqrestore(&ec->curr_lock, tmp);
296         /* if we selected poll mode or failed in GPE-mode do a poll loop */
297         if (force_poll ||
298             !test_bit(EC_FLAGS_GPE_MODE, &ec->flags) ||
299             acpi_ec_wait(ec))
300                 ret = ec_poll(ec);
301         pr_debug(PREFIX "transaction end\n");
302         spin_lock_irqsave(&ec->curr_lock, tmp);
303         ec->curr = NULL;
304         spin_unlock_irqrestore(&ec->curr_lock, tmp);
305         if (test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
306                 /* check if we received SCI during transaction */
307                 ec_check_sci(ec, acpi_ec_read_status(ec));
308                 /* it is safe to enable GPE outside of transaction */
309                 acpi_enable_gpe(NULL, ec->gpe);
310         } else if (test_bit(EC_FLAGS_GPE_MODE, &ec->flags) &&
311                    t->irq_count > ACPI_EC_STORM_THRESHOLD) {
312                 pr_info(PREFIX "GPE storm detected, "
313                         "transactions will use polling mode\n");
314                 set_bit(EC_FLAGS_GPE_STORM, &ec->flags);
315         }
316         return ret;
317 }
318
319 static int ec_check_ibf0(struct acpi_ec *ec)
320 {
321         u8 status = acpi_ec_read_status(ec);
322         return (status & ACPI_EC_FLAG_IBF) == 0;
323 }
324
325 static int ec_wait_ibf0(struct acpi_ec *ec)
326 {
327         unsigned long delay = jiffies + msecs_to_jiffies(ACPI_EC_DELAY);
328         /* interrupt wait manually if GPE mode is not active */
329         unsigned long timeout = test_bit(EC_FLAGS_GPE_MODE, &ec->flags) ?
330                 msecs_to_jiffies(ACPI_EC_DELAY) : msecs_to_jiffies(1);
331         while (time_before(jiffies, delay))
332                 if (wait_event_timeout(ec->wait, ec_check_ibf0(ec), timeout))
333                         return 0;
334         return -ETIME;
335 }
336
337 static int acpi_ec_transaction(struct acpi_ec *ec, struct transaction *t,
338                                int force_poll)
339 {
340         int status;
341         u32 glk;
342         if (!ec || (!t) || (t->wlen && !t->wdata) || (t->rlen && !t->rdata))
343                 return -EINVAL;
344         if (t->rdata)
345                 memset(t->rdata, 0, t->rlen);
346         mutex_lock(&ec->lock);
347         if (ec->global_lock) {
348                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
349                 if (ACPI_FAILURE(status)) {
350                         status = -ENODEV;
351                         goto unlock;
352                 }
353         }
354         if (ec_wait_ibf0(ec)) {
355                 pr_err(PREFIX "input buffer is not empty, "
356                                 "aborting transaction\n");
357                 status = -ETIME;
358                 goto end;
359         }
360         status = acpi_ec_transaction_unlocked(ec, t, force_poll);
361 end:
362         if (ec->global_lock)
363                 acpi_release_global_lock(glk);
364 unlock:
365         mutex_unlock(&ec->lock);
366         return status;
367 }
368
369 /*
370  * Note: samsung nv5000 doesn't work with ec burst mode.
371  * http://bugzilla.kernel.org/show_bug.cgi?id=4980
372  */
373 int acpi_ec_burst_enable(struct acpi_ec *ec)
374 {
375         u8 d;
376         struct transaction t = {.command = ACPI_EC_BURST_ENABLE,
377                                 .wdata = NULL, .rdata = &d,
378                                 .wlen = 0, .rlen = 1};
379
380         return acpi_ec_transaction(ec, &t, 0);
381 }
382
383 int acpi_ec_burst_disable(struct acpi_ec *ec)
384 {
385         struct transaction t = {.command = ACPI_EC_BURST_DISABLE,
386                                 .wdata = NULL, .rdata = NULL,
387                                 .wlen = 0, .rlen = 0};
388
389         return (acpi_ec_read_status(ec) & ACPI_EC_FLAG_BURST) ?
390                                 acpi_ec_transaction(ec, &t, 0) : 0;
391 }
392
393 static int acpi_ec_read(struct acpi_ec *ec, u8 address, u8 * data)
394 {
395         int result;
396         u8 d;
397         struct transaction t = {.command = ACPI_EC_COMMAND_READ,
398                                 .wdata = &address, .rdata = &d,
399                                 .wlen = 1, .rlen = 1};
400
401         result = acpi_ec_transaction(ec, &t, 0);
402         *data = d;
403         return result;
404 }
405
406 static int acpi_ec_write(struct acpi_ec *ec, u8 address, u8 data)
407 {
408         u8 wdata[2] = { address, data };
409         struct transaction t = {.command = ACPI_EC_COMMAND_WRITE,
410                                 .wdata = wdata, .rdata = NULL,
411                                 .wlen = 2, .rlen = 0};
412
413         return acpi_ec_transaction(ec, &t, 0);
414 }
415
416 /*
417  * Externally callable EC access functions. For now, assume 1 EC only
418  */
419 int ec_burst_enable(void)
420 {
421         if (!first_ec)
422                 return -ENODEV;
423         return acpi_ec_burst_enable(first_ec);
424 }
425
426 EXPORT_SYMBOL(ec_burst_enable);
427
428 int ec_burst_disable(void)
429 {
430         if (!first_ec)
431                 return -ENODEV;
432         return acpi_ec_burst_disable(first_ec);
433 }
434
435 EXPORT_SYMBOL(ec_burst_disable);
436
437 int ec_read(u8 addr, u8 * val)
438 {
439         int err;
440         u8 temp_data;
441
442         if (!first_ec)
443                 return -ENODEV;
444
445         err = acpi_ec_read(first_ec, addr, &temp_data);
446
447         if (!err) {
448                 *val = temp_data;
449                 return 0;
450         } else
451                 return err;
452 }
453
454 EXPORT_SYMBOL(ec_read);
455
456 int ec_write(u8 addr, u8 val)
457 {
458         int err;
459
460         if (!first_ec)
461                 return -ENODEV;
462
463         err = acpi_ec_write(first_ec, addr, val);
464
465         return err;
466 }
467
468 EXPORT_SYMBOL(ec_write);
469
470 int ec_transaction(u8 command,
471                    const u8 * wdata, unsigned wdata_len,
472                    u8 * rdata, unsigned rdata_len,
473                    int force_poll)
474 {
475         struct transaction t = {.command = command,
476                                 .wdata = wdata, .rdata = rdata,
477                                 .wlen = wdata_len, .rlen = rdata_len};
478         if (!first_ec)
479                 return -ENODEV;
480
481         return acpi_ec_transaction(first_ec, &t, force_poll);
482 }
483
484 EXPORT_SYMBOL(ec_transaction);
485
486 static int acpi_ec_query(struct acpi_ec *ec, u8 * data)
487 {
488         int result;
489         u8 d;
490         struct transaction t = {.command = ACPI_EC_COMMAND_QUERY,
491                                 .wdata = NULL, .rdata = &d,
492                                 .wlen = 0, .rlen = 1};
493         if (!ec || !data)
494                 return -EINVAL;
495
496         /*
497          * Query the EC to find out which _Qxx method we need to evaluate.
498          * Note that successful completion of the query causes the ACPI_EC_SCI
499          * bit to be cleared (and thus clearing the interrupt source).
500          */
501
502         result = acpi_ec_transaction(ec, &t, 0);
503         if (result)
504                 return result;
505
506         if (!d)
507                 return -ENODATA;
508
509         *data = d;
510         return 0;
511 }
512
513 /* --------------------------------------------------------------------------
514                                 Event Management
515    -------------------------------------------------------------------------- */
516 int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
517                               acpi_handle handle, acpi_ec_query_func func,
518                               void *data)
519 {
520         struct acpi_ec_query_handler *handler =
521             kzalloc(sizeof(struct acpi_ec_query_handler), GFP_KERNEL);
522         if (!handler)
523                 return -ENOMEM;
524
525         handler->query_bit = query_bit;
526         handler->handle = handle;
527         handler->func = func;
528         handler->data = data;
529         mutex_lock(&ec->lock);
530         list_add(&handler->node, &ec->list);
531         mutex_unlock(&ec->lock);
532         return 0;
533 }
534
535 EXPORT_SYMBOL_GPL(acpi_ec_add_query_handler);
536
537 void acpi_ec_remove_query_handler(struct acpi_ec *ec, u8 query_bit)
538 {
539         struct acpi_ec_query_handler *handler, *tmp;
540         mutex_lock(&ec->lock);
541         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
542                 if (query_bit == handler->query_bit) {
543                         list_del(&handler->node);
544                         kfree(handler);
545                 }
546         }
547         mutex_unlock(&ec->lock);
548 }
549
550 EXPORT_SYMBOL_GPL(acpi_ec_remove_query_handler);
551
552 static void acpi_ec_gpe_query(void *ec_cxt)
553 {
554         struct acpi_ec *ec = ec_cxt;
555         u8 value = 0;
556         struct acpi_ec_query_handler *handler, copy;
557
558         if (!ec || acpi_ec_query(ec, &value))
559                 return;
560         mutex_lock(&ec->lock);
561         list_for_each_entry(handler, &ec->list, node) {
562                 if (value == handler->query_bit) {
563                         /* have custom handler for this bit */
564                         memcpy(&copy, handler, sizeof(copy));
565                         mutex_unlock(&ec->lock);
566                         if (copy.func) {
567                                 copy.func(copy.data);
568                         } else if (copy.handle) {
569                                 acpi_evaluate_object(copy.handle, NULL, NULL, NULL);
570                         }
571                         return;
572                 }
573         }
574         mutex_unlock(&ec->lock);
575 }
576
577 static u32 acpi_ec_gpe_handler(void *data)
578 {
579         struct acpi_ec *ec = data;
580         u8 status;
581
582         pr_debug(PREFIX "~~~> interrupt\n");
583         status = acpi_ec_read_status(ec);
584
585         if (test_bit(EC_FLAGS_GPE_MODE, &ec->flags)) {
586                 gpe_transaction(ec, status);
587                 if (ec_transaction_done(ec) &&
588                     (status & ACPI_EC_FLAG_IBF) == 0)
589                         wake_up(&ec->wait);
590         }
591
592         ec_check_sci(ec, status);
593         if (!test_bit(EC_FLAGS_GPE_MODE, &ec->flags) &&
594             !test_bit(EC_FLAGS_NO_GPE, &ec->flags)) {
595                 /* this is non-query, must be confirmation */
596                 if (!test_bit(EC_FLAGS_GPE_STORM, &ec->flags)) {
597                         if (printk_ratelimit())
598                                 pr_info(PREFIX "non-query interrupt received,"
599                                         " switching to interrupt mode\n");
600                 } else {
601                         /* hush, STORM switches the mode every transaction */
602                         pr_debug(PREFIX "non-query interrupt received,"
603                                 " switching to interrupt mode\n");
604                 }
605                 set_bit(EC_FLAGS_GPE_MODE, &ec->flags);
606         }
607         return ACPI_INTERRUPT_HANDLED;
608 }
609
610 /* --------------------------------------------------------------------------
611                              Address Space Management
612    -------------------------------------------------------------------------- */
613
614 static acpi_status
615 acpi_ec_space_handler(u32 function, acpi_physical_address address,
616                       u32 bits, acpi_integer *value,
617                       void *handler_context, void *region_context)
618 {
619         struct acpi_ec *ec = handler_context;
620         int result = 0, i;
621         u8 temp = 0;
622
623         if ((address > 0xFF) || !value || !handler_context)
624                 return AE_BAD_PARAMETER;
625
626         if (function != ACPI_READ && function != ACPI_WRITE)
627                 return AE_BAD_PARAMETER;
628
629         if (bits != 8 && acpi_strict)
630                 return AE_BAD_PARAMETER;
631
632         acpi_ec_burst_enable(ec);
633
634         if (function == ACPI_READ) {
635                 result = acpi_ec_read(ec, address, &temp);
636                 *value = temp;
637         } else {
638                 temp = 0xff & (*value);
639                 result = acpi_ec_write(ec, address, temp);
640         }
641
642         for (i = 8; unlikely(bits - i > 0); i += 8) {
643                 ++address;
644                 if (function == ACPI_READ) {
645                         result = acpi_ec_read(ec, address, &temp);
646                         (*value) |= ((acpi_integer)temp) << i;
647                 } else {
648                         temp = 0xff & ((*value) >> i);
649                         result = acpi_ec_write(ec, address, temp);
650                 }
651         }
652
653         acpi_ec_burst_disable(ec);
654
655         switch (result) {
656         case -EINVAL:
657                 return AE_BAD_PARAMETER;
658                 break;
659         case -ENODEV:
660                 return AE_NOT_FOUND;
661                 break;
662         case -ETIME:
663                 return AE_TIME;
664                 break;
665         default:
666                 return AE_OK;
667         }
668 }
669
670 /* --------------------------------------------------------------------------
671                               FS Interface (/proc)
672    -------------------------------------------------------------------------- */
673
674 static struct proc_dir_entry *acpi_ec_dir;
675
676 static int acpi_ec_read_info(struct seq_file *seq, void *offset)
677 {
678         struct acpi_ec *ec = seq->private;
679
680         if (!ec)
681                 goto end;
682
683         seq_printf(seq, "gpe:\t\t\t0x%02x\n", (u32) ec->gpe);
684         seq_printf(seq, "ports:\t\t\t0x%02x, 0x%02x\n",
685                    (unsigned)ec->command_addr, (unsigned)ec->data_addr);
686         seq_printf(seq, "use global lock:\t%s\n",
687                    ec->global_lock ? "yes" : "no");
688       end:
689         return 0;
690 }
691
692 static int acpi_ec_info_open_fs(struct inode *inode, struct file *file)
693 {
694         return single_open(file, acpi_ec_read_info, PDE(inode)->data);
695 }
696
697 static struct file_operations acpi_ec_info_ops = {
698         .open = acpi_ec_info_open_fs,
699         .read = seq_read,
700         .llseek = seq_lseek,
701         .release = single_release,
702         .owner = THIS_MODULE,
703 };
704
705 static int acpi_ec_add_fs(struct acpi_device *device)
706 {
707         struct proc_dir_entry *entry = NULL;
708
709         if (!acpi_device_dir(device)) {
710                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
711                                                      acpi_ec_dir);
712                 if (!acpi_device_dir(device))
713                         return -ENODEV;
714         }
715
716         entry = proc_create_data(ACPI_EC_FILE_INFO, S_IRUGO,
717                                  acpi_device_dir(device),
718                                  &acpi_ec_info_ops, acpi_driver_data(device));
719         if (!entry)
720                 return -ENODEV;
721         return 0;
722 }
723
724 static int acpi_ec_remove_fs(struct acpi_device *device)
725 {
726
727         if (acpi_device_dir(device)) {
728                 remove_proc_entry(ACPI_EC_FILE_INFO, acpi_device_dir(device));
729                 remove_proc_entry(acpi_device_bid(device), acpi_ec_dir);
730                 acpi_device_dir(device) = NULL;
731         }
732
733         return 0;
734 }
735
736 /* --------------------------------------------------------------------------
737                                Driver Interface
738    -------------------------------------------------------------------------- */
739 static acpi_status
740 ec_parse_io_ports(struct acpi_resource *resource, void *context);
741
742 static struct acpi_ec *make_acpi_ec(void)
743 {
744         struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
745         if (!ec)
746                 return NULL;
747         ec->flags = 1 << EC_FLAGS_QUERY_PENDING;
748         mutex_init(&ec->lock);
749         init_waitqueue_head(&ec->wait);
750         INIT_LIST_HEAD(&ec->list);
751         spin_lock_init(&ec->curr_lock);
752         return ec;
753 }
754
755 static acpi_status
756 acpi_ec_register_query_methods(acpi_handle handle, u32 level,
757                                void *context, void **return_value)
758 {
759         struct acpi_namespace_node *node = handle;
760         struct acpi_ec *ec = context;
761         int value = 0;
762         if (sscanf(node->name.ascii, "_Q%x", &value) == 1) {
763                 acpi_ec_add_query_handler(ec, value, handle, NULL, NULL);
764         }
765         return AE_OK;
766 }
767
768 static acpi_status
769 ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval)
770 {
771         acpi_status status;
772         unsigned long long tmp = 0;
773
774         struct acpi_ec *ec = context;
775         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
776                                      ec_parse_io_ports, ec);
777         if (ACPI_FAILURE(status))
778                 return status;
779
780         /* Get GPE bit assignment (EC events). */
781         /* TODO: Add support for _GPE returning a package */
782         status = acpi_evaluate_integer(handle, "_GPE", NULL, &tmp);
783         if (ACPI_FAILURE(status))
784                 return status;
785         ec->gpe = tmp;
786         /* Use the global lock for all EC transactions? */
787         tmp = 0;
788         acpi_evaluate_integer(handle, "_GLK", NULL, &tmp);
789         ec->global_lock = tmp;
790         ec->handle = handle;
791         return AE_CTRL_TERMINATE;
792 }
793
794 static void ec_remove_handlers(struct acpi_ec *ec)
795 {
796         if (ACPI_FAILURE(acpi_remove_address_space_handler(ec->handle,
797                                 ACPI_ADR_SPACE_EC, &acpi_ec_space_handler)))
798                 pr_err(PREFIX "failed to remove space handler\n");
799         if (ACPI_FAILURE(acpi_remove_gpe_handler(NULL, ec->gpe,
800                                 &acpi_ec_gpe_handler)))
801                 pr_err(PREFIX "failed to remove gpe handler\n");
802         clear_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
803 }
804
805 static int acpi_ec_add(struct acpi_device *device)
806 {
807         struct acpi_ec *ec = NULL;
808
809         if (!device)
810                 return -EINVAL;
811         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
812         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
813
814         /* Check for boot EC */
815         if (boot_ec &&
816             (boot_ec->handle == device->handle ||
817              boot_ec->handle == ACPI_ROOT_OBJECT)) {
818                 ec = boot_ec;
819                 boot_ec = NULL;
820         } else {
821                 ec = make_acpi_ec();
822                 if (!ec)
823                         return -ENOMEM;
824                 if (ec_parse_device(device->handle, 0, ec, NULL) !=
825                     AE_CTRL_TERMINATE) {
826                         kfree(ec);
827                         return -EINVAL;
828                 }
829         }
830
831         ec->handle = device->handle;
832
833         /* Find and register all query methods */
834         acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1,
835                             acpi_ec_register_query_methods, ec, NULL);
836
837         if (!first_ec)
838                 first_ec = ec;
839         device->driver_data = ec;
840         acpi_ec_add_fs(device);
841         pr_info(PREFIX "GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n",
842                           ec->gpe, ec->command_addr, ec->data_addr);
843         pr_info(PREFIX "driver started in %s mode\n",
844                 (test_bit(EC_FLAGS_GPE_MODE, &ec->flags))?"interrupt":"poll");
845         return 0;
846 }
847
848 static int acpi_ec_remove(struct acpi_device *device, int type)
849 {
850         struct acpi_ec *ec;
851         struct acpi_ec_query_handler *handler, *tmp;
852
853         if (!device)
854                 return -EINVAL;
855
856         ec = acpi_driver_data(device);
857         mutex_lock(&ec->lock);
858         list_for_each_entry_safe(handler, tmp, &ec->list, node) {
859                 list_del(&handler->node);
860                 kfree(handler);
861         }
862         mutex_unlock(&ec->lock);
863         acpi_ec_remove_fs(device);
864         device->driver_data = NULL;
865         if (ec == first_ec)
866                 first_ec = NULL;
867         kfree(ec);
868         return 0;
869 }
870
871 static acpi_status
872 ec_parse_io_ports(struct acpi_resource *resource, void *context)
873 {
874         struct acpi_ec *ec = context;
875
876         if (resource->type != ACPI_RESOURCE_TYPE_IO)
877                 return AE_OK;
878
879         /*
880          * The first address region returned is the data port, and
881          * the second address region returned is the status/command
882          * port.
883          */
884         if (ec->data_addr == 0)
885                 ec->data_addr = resource->data.io.minimum;
886         else if (ec->command_addr == 0)
887                 ec->command_addr = resource->data.io.minimum;
888         else
889                 return AE_CTRL_TERMINATE;
890
891         return AE_OK;
892 }
893
894 static int ec_install_handlers(struct acpi_ec *ec)
895 {
896         acpi_status status;
897         if (test_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags))
898                 return 0;
899         status = acpi_install_gpe_handler(NULL, ec->gpe,
900                                   ACPI_GPE_EDGE_TRIGGERED,
901                                   &acpi_ec_gpe_handler, ec);
902         if (ACPI_FAILURE(status))
903                 return -ENODEV;
904         acpi_set_gpe_type(NULL, ec->gpe, ACPI_GPE_TYPE_RUNTIME);
905         acpi_enable_gpe(NULL, ec->gpe);
906         status = acpi_install_address_space_handler(ec->handle,
907                                                     ACPI_ADR_SPACE_EC,
908                                                     &acpi_ec_space_handler,
909                                                     NULL, ec);
910         if (ACPI_FAILURE(status)) {
911                 if (status == AE_NOT_FOUND) {
912                         /*
913                          * Maybe OS fails in evaluating the _REG object.
914                          * The AE_NOT_FOUND error will be ignored and OS
915                          * continue to initialize EC.
916                          */
917                         printk(KERN_ERR "Fail in evaluating the _REG object"
918                                 " of EC device. Broken bios is suspected.\n");
919                 } else {
920                         acpi_remove_gpe_handler(NULL, ec->gpe,
921                                 &acpi_ec_gpe_handler);
922                         return -ENODEV;
923                 }
924         }
925
926         set_bit(EC_FLAGS_HANDLERS_INSTALLED, &ec->flags);
927         return 0;
928 }
929
930 static int acpi_ec_start(struct acpi_device *device)
931 {
932         struct acpi_ec *ec;
933         int ret = 0;
934
935         if (!device)
936                 return -EINVAL;
937
938         ec = acpi_driver_data(device);
939
940         if (!ec)
941                 return -EINVAL;
942
943         ret = ec_install_handlers(ec);
944
945         /* EC is fully operational, allow queries */
946         clear_bit(EC_FLAGS_QUERY_PENDING, &ec->flags);
947         return ret;
948 }
949
950 static int acpi_ec_stop(struct acpi_device *device, int type)
951 {
952         struct acpi_ec *ec;
953         if (!device)
954                 return -EINVAL;
955         ec = acpi_driver_data(device);
956         if (!ec)
957                 return -EINVAL;
958         ec_remove_handlers(ec);
959
960         return 0;
961 }
962
963 int __init acpi_boot_ec_enable(void)
964 {
965         if (!boot_ec || test_bit(EC_FLAGS_HANDLERS_INSTALLED, &boot_ec->flags))
966                 return 0;
967         if (!ec_install_handlers(boot_ec)) {
968                 first_ec = boot_ec;
969                 return 0;
970         }
971         return -EFAULT;
972 }
973
974 static const struct acpi_device_id ec_device_ids[] = {
975         {"PNP0C09", 0},
976         {"", 0},
977 };
978
979 int __init acpi_ec_ecdt_probe(void)
980 {
981         int ret;
982         acpi_status status;
983         struct acpi_table_ecdt *ecdt_ptr;
984
985         boot_ec = make_acpi_ec();
986         if (!boot_ec)
987                 return -ENOMEM;
988         /*
989          * Generate a boot ec context
990          */
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                 if (dmi_check_system(ec_dmi_table)) {
998                         /*
999                          * If the board falls into ec_dmi_table, it means
1000                          * that ECDT table gives the incorrect command/status
1001                          * & data I/O address. Just fix it.
1002                          */
1003                         boot_ec->data_addr = ecdt_ptr->control.address;
1004                         boot_ec->command_addr = ecdt_ptr->data.address;
1005                 }
1006                 boot_ec->gpe = ecdt_ptr->gpe;
1007                 boot_ec->handle = ACPI_ROOT_OBJECT;
1008                 acpi_get_handle(ACPI_ROOT_OBJECT, ecdt_ptr->id, &boot_ec->handle);
1009         } else {
1010                 /* This workaround is needed only on some broken machines,
1011                  * which require early EC, but fail to provide ECDT */
1012                 acpi_handle x;
1013                 printk(KERN_DEBUG PREFIX "Look up EC in DSDT\n");
1014                 status = acpi_get_devices(ec_device_ids[0].id, ec_parse_device,
1015                                                 boot_ec, NULL);
1016                 /* Check that acpi_get_devices actually find something */
1017                 if (ACPI_FAILURE(status) || !boot_ec->handle)
1018                         goto error;
1019                 /* We really need to limit this workaround, the only ASUS,
1020                  * which needs it, has fake EC._INI method, so use it as flag.
1021                  * Keep boot_ec struct as it will be needed soon.
1022                  */
1023                 if (ACPI_FAILURE(acpi_get_handle(boot_ec->handle, "_INI", &x)))
1024                         return -ENODEV;
1025         }
1026
1027         ret = ec_install_handlers(boot_ec);
1028         if (!ret) {
1029                 first_ec = boot_ec;
1030                 return 0;
1031         }
1032       error:
1033         kfree(boot_ec);
1034         boot_ec = NULL;
1035         return -ENODEV;
1036 }
1037
1038 static int acpi_ec_suspend(struct acpi_device *device, pm_message_t state)
1039 {
1040         struct acpi_ec *ec = acpi_driver_data(device);
1041         /* Stop using GPE */
1042         set_bit(EC_FLAGS_NO_GPE, &ec->flags);
1043         clear_bit(EC_FLAGS_GPE_MODE, &ec->flags);
1044         acpi_disable_gpe(NULL, ec->gpe);
1045         return 0;
1046 }
1047
1048 static int acpi_ec_resume(struct acpi_device *device)
1049 {
1050         struct acpi_ec *ec = acpi_driver_data(device);
1051         /* Enable use of GPE back */
1052         clear_bit(EC_FLAGS_NO_GPE, &ec->flags);
1053         acpi_enable_gpe(NULL, ec->gpe);
1054         return 0;
1055 }
1056
1057 static struct acpi_driver acpi_ec_driver = {
1058         .name = "ec",
1059         .class = ACPI_EC_CLASS,
1060         .ids = ec_device_ids,
1061         .ops = {
1062                 .add = acpi_ec_add,
1063                 .remove = acpi_ec_remove,
1064                 .start = acpi_ec_start,
1065                 .stop = acpi_ec_stop,
1066                 .suspend = acpi_ec_suspend,
1067                 .resume = acpi_ec_resume,
1068                 },
1069 };
1070
1071 static int __init acpi_ec_init(void)
1072 {
1073         int result = 0;
1074
1075         if (acpi_disabled)
1076                 return 0;
1077
1078         acpi_ec_dir = proc_mkdir(ACPI_EC_CLASS, acpi_root_dir);
1079         if (!acpi_ec_dir)
1080                 return -ENODEV;
1081
1082         /* Now register the driver for the EC */
1083         result = acpi_bus_register_driver(&acpi_ec_driver);
1084         if (result < 0) {
1085                 remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1086                 return -ENODEV;
1087         }
1088
1089         return result;
1090 }
1091
1092 subsys_initcall(acpi_ec_init);
1093
1094 /* EC driver currently not unloadable */
1095 #if 0
1096 static void __exit acpi_ec_exit(void)
1097 {
1098
1099         acpi_bus_unregister_driver(&acpi_ec_driver);
1100
1101         remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1102
1103         return;
1104 }
1105 #endif  /* 0 */