8c5d7df7d34310aacf61fb7632392de376fb61c0
[linux-3.10.git] / drivers / acpi / ec.c
1 /*
2  *  acpi_ec.c - ACPI Embedded Controller Driver ($Revision: 38 $)
3  *
4  *  Copyright (C) 2004 Luming Yu <luming.yu@intel.com>
5  *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
6  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
7  *
8  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
9  *
10  *  This program is free software; you can redistribute it and/or modify
11  *  it under the terms of the GNU General Public License as published by
12  *  the Free Software Foundation; either version 2 of the License, or (at
13  *  your option) any later version.
14  *
15  *  This program is distributed in the hope that it will be useful, but
16  *  WITHOUT ANY WARRANTY; without even the implied warranty of
17  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
18  *  General Public License for more details.
19  *
20  *  You should have received a copy of the GNU General Public License along
21  *  with this program; if not, write to the Free Software Foundation, Inc.,
22  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
23  *
24  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
25  */
26
27 #include <linux/kernel.h>
28 #include <linux/module.h>
29 #include <linux/init.h>
30 #include <linux/types.h>
31 #include <linux/delay.h>
32 #include <linux/proc_fs.h>
33 #include <linux/seq_file.h>
34 #include <linux/interrupt.h>
35 #include <asm/io.h>
36 #include <acpi/acpi_bus.h>
37 #include <acpi/acpi_drivers.h>
38 #include <acpi/actypes.h>
39
40 #define _COMPONENT              ACPI_EC_COMPONENT
41 ACPI_MODULE_NAME("acpi_ec")
42 #define ACPI_EC_COMPONENT               0x00100000
43 #define ACPI_EC_CLASS                   "embedded_controller"
44 #define ACPI_EC_HID                     "PNP0C09"
45 #define ACPI_EC_DRIVER_NAME             "ACPI Embedded Controller Driver"
46 #define ACPI_EC_DEVICE_NAME             "Embedded Controller"
47 #define ACPI_EC_FILE_INFO               "info"
48 #define ACPI_EC_FLAG_OBF        0x01    /* Output buffer full */
49 #define ACPI_EC_FLAG_IBF        0x02    /* Input buffer full */
50 #define ACPI_EC_FLAG_BURST      0x10    /* burst mode */
51 #define ACPI_EC_FLAG_SCI        0x20    /* EC-SCI occurred */
52 #define ACPI_EC_EVENT_OBF       0x01    /* Output buffer full */
53 #define ACPI_EC_EVENT_IBE       0x02    /* Input buffer empty */
54 #define ACPI_EC_DELAY           50      /* Wait 50ms max. during EC ops */
55 #define ACPI_EC_UDELAY_GLK      1000    /* Wait 1ms max. to get global lock */
56 #define ACPI_EC_UDELAY         100      /* Poll @ 100us increments */
57 #define ACPI_EC_UDELAY_COUNT   1000     /* Wait 10ms max. during EC ops */
58 #define ACPI_EC_COMMAND_READ    0x80
59 #define ACPI_EC_COMMAND_WRITE   0x81
60 #define ACPI_EC_BURST_ENABLE    0x82
61 #define ACPI_EC_BURST_DISABLE   0x83
62 #define ACPI_EC_COMMAND_QUERY   0x84
63 #define EC_POLL                 0xFF
64 #define EC_INTR                 0x00
65 static int acpi_ec_remove(struct acpi_device *device, int type);
66 static int acpi_ec_start(struct acpi_device *device);
67 static int acpi_ec_stop(struct acpi_device *device, int type);
68 static int acpi_ec_intr_add(struct acpi_device *device);
69 static int acpi_ec_poll_add(struct acpi_device *device);
70
71 static struct acpi_driver acpi_ec_driver = {
72         .name = ACPI_EC_DRIVER_NAME,
73         .class = ACPI_EC_CLASS,
74         .ids = ACPI_EC_HID,
75         .ops = {
76                 .add = acpi_ec_intr_add,
77                 .remove = acpi_ec_remove,
78                 .start = acpi_ec_start,
79                 .stop = acpi_ec_stop,
80                 },
81 };
82 union acpi_ec {
83         struct {
84                 u32 mode;
85                 acpi_handle handle;
86                 unsigned long uid;
87                 unsigned long gpe_bit;
88                 struct acpi_generic_address status_addr;
89                 struct acpi_generic_address command_addr;
90                 struct acpi_generic_address data_addr;
91                 unsigned long global_lock;
92         } common;
93
94         struct {
95                 u32 mode;
96                 acpi_handle handle;
97                 unsigned long uid;
98                 unsigned long gpe_bit;
99                 struct acpi_generic_address status_addr;
100                 struct acpi_generic_address command_addr;
101                 struct acpi_generic_address data_addr;
102                 unsigned long global_lock;
103                 unsigned int expect_event;
104                 atomic_t leaving_burst; /* 0 : No, 1 : Yes, 2: abort */
105                 atomic_t pending_gpe;
106                 struct semaphore sem;
107                 wait_queue_head_t wait;
108         } intr;
109
110         struct {
111                 u32 mode;
112                 acpi_handle handle;
113                 unsigned long uid;
114                 unsigned long gpe_bit;
115                 struct acpi_generic_address status_addr;
116                 struct acpi_generic_address command_addr;
117                 struct acpi_generic_address data_addr;
118                 unsigned long global_lock;
119                 struct semaphore sem;
120         } poll;
121 };
122
123 static int acpi_ec_poll_wait(union acpi_ec *ec, u8 event);
124 static int acpi_ec_intr_wait(union acpi_ec *ec, unsigned int event);
125 static int acpi_ec_poll_read(union acpi_ec *ec, u8 address, u32 * data);
126 static int acpi_ec_intr_read(union acpi_ec *ec, u8 address, u32 * data);
127 static int acpi_ec_poll_write(union acpi_ec *ec, u8 address, u8 data);
128 static int acpi_ec_intr_write(union acpi_ec *ec, u8 address, u8 data);
129 static int acpi_ec_poll_query(union acpi_ec *ec, u32 * data);
130 static int acpi_ec_intr_query(union acpi_ec *ec, u32 * data);
131 static void acpi_ec_gpe_poll_query(void *ec_cxt);
132 static void acpi_ec_gpe_intr_query(void *ec_cxt);
133 static u32 acpi_ec_gpe_poll_handler(void *data);
134 static u32 acpi_ec_gpe_intr_handler(void *data);
135 static acpi_status __init
136 acpi_fake_ecdt_poll_callback(acpi_handle handle,
137                                 u32 Level, void *context, void **retval);
138
139 static acpi_status __init
140 acpi_fake_ecdt_intr_callback(acpi_handle handle,
141                               u32 Level, void *context, void **retval);
142
143 static int __init acpi_ec_poll_get_real_ecdt(void);
144 static int __init acpi_ec_intr_get_real_ecdt(void);
145 /* If we find an EC via the ECDT, we need to keep a ptr to its context */
146 static union acpi_ec *ec_ecdt;
147
148 /* External interfaces use first EC only, so remember */
149 static struct acpi_device *first_ec;
150 static int acpi_ec_poll_mode = EC_INTR;
151
152 /* --------------------------------------------------------------------------
153                              Transaction Management
154    -------------------------------------------------------------------------- */
155
156 static u32 acpi_ec_read_status(union acpi_ec *ec)
157 {
158         u32 status = 0;
159
160         acpi_hw_low_level_read(8, &status, &ec->common.status_addr);
161         return status;
162 }
163
164 static int acpi_ec_wait(union acpi_ec *ec, u8 event)
165 {
166         if (acpi_ec_poll_mode)
167                 return acpi_ec_poll_wait(ec, event);
168         else
169                 return acpi_ec_intr_wait(ec, event);
170 }
171
172 static int acpi_ec_poll_wait(union acpi_ec *ec, u8 event)
173 {
174         u32 acpi_ec_status = 0;
175         u32 i = ACPI_EC_UDELAY_COUNT;
176
177         if (!ec)
178                 return -EINVAL;
179
180         /* Poll the EC status register waiting for the event to occur. */
181         switch (event) {
182         case ACPI_EC_EVENT_OBF:
183                 do {
184                         acpi_hw_low_level_read(8, &acpi_ec_status,
185                                                &ec->common.status_addr);
186                         if (acpi_ec_status & ACPI_EC_FLAG_OBF)
187                                 return 0;
188                         udelay(ACPI_EC_UDELAY);
189                 } while (--i > 0);
190                 break;
191         case ACPI_EC_EVENT_IBE:
192                 do {
193                         acpi_hw_low_level_read(8, &acpi_ec_status,
194                                                &ec->common.status_addr);
195                         if (!(acpi_ec_status & ACPI_EC_FLAG_IBF))
196                                 return 0;
197                         udelay(ACPI_EC_UDELAY);
198                 } while (--i > 0);
199                 break;
200         default:
201                 return -EINVAL;
202         }
203
204         return -ETIME;
205 }
206 static int acpi_ec_intr_wait(union acpi_ec *ec, unsigned int event)
207 {
208         int result = 0;
209
210
211         ec->intr.expect_event = event;
212         smp_mb();
213
214         switch (event) {
215         case ACPI_EC_EVENT_IBE:
216                 if (~acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF) {
217                         ec->intr.expect_event = 0;
218                         return 0;
219                 }
220                 break;
221         default:
222                 break;
223         }
224
225         result = wait_event_timeout(ec->intr.wait,
226                                     !ec->intr.expect_event,
227                                     msecs_to_jiffies(ACPI_EC_DELAY));
228
229         ec->intr.expect_event = 0;
230         smp_mb();
231
232         /*
233          * Verify that the event in question has actually happened by
234          * querying EC status. Do the check even if operation timed-out
235          * to make sure that we did not miss interrupt.
236          */
237         switch (event) {
238         case ACPI_EC_EVENT_OBF:
239                 if (acpi_ec_read_status(ec) & ACPI_EC_FLAG_OBF)
240                         return 0;
241                 break;
242
243         case ACPI_EC_EVENT_IBE:
244                 if (~acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF)
245                         return 0;
246                 break;
247         }
248
249         return -ETIME;
250 }
251
252 #ifdef ACPI_FUTURE_USAGE
253 /*
254  * Note: samsung nv5000 doesn't work with ec burst mode.
255  * http://bugzilla.kernel.org/show_bug.cgi?id=4980
256  */
257 int acpi_ec_enter_burst_mode(union acpi_ec *ec)
258 {
259         u32 tmp = 0;
260         int status = 0;
261
262
263         status = acpi_ec_read_status(ec);
264         if (status != -EINVAL && !(status & ACPI_EC_FLAG_BURST)) {
265                 status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
266                 if (status)
267                         goto end;
268                 acpi_hw_low_level_write(8, ACPI_EC_BURST_ENABLE,
269                                         &ec->common.command_addr);
270                 status = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF);
271                 acpi_hw_low_level_read(8, &tmp, &ec->common.data_addr);
272                 if (tmp != 0x90) {      /* Burst ACK byte */
273                         return -EINVAL;
274                 }
275         }
276
277         atomic_set(&ec->intr.leaving_burst, 0);
278         return 0;
279       end:
280         ACPI_EXCEPTION ((AE_INFO, status, "EC wait, burst mode");
281         return -1;
282 }
283
284 int acpi_ec_leave_burst_mode(union acpi_ec *ec)
285 {
286         int status = 0;
287
288
289         status = acpi_ec_read_status(ec);
290         if (status != -EINVAL && (status & ACPI_EC_FLAG_BURST)){
291                 status = acpi_ec_wait(ec, ACPI_EC_FLAG_IBF);
292                 if(status)
293                         goto end;
294                 acpi_hw_low_level_write(8, ACPI_EC_BURST_DISABLE, &ec->common.command_addr);
295                 acpi_ec_wait(ec, ACPI_EC_FLAG_IBF);
296         } 
297         atomic_set(&ec->intr.leaving_burst, 1);
298         return 0;
299 end:
300         ACPI_EXCEPTION((AE_INFO, status, "EC leave burst mode");
301         return -1;
302 }
303 #endif /* ACPI_FUTURE_USAGE */
304
305 static int acpi_ec_read(union acpi_ec *ec, u8 address, u32 * data)
306 {
307         if (acpi_ec_poll_mode)
308                 return acpi_ec_poll_read(ec, address, data);
309         else
310                 return acpi_ec_intr_read(ec, address, data);
311 }
312 static int acpi_ec_write(union acpi_ec *ec, u8 address, u8 data)
313 {
314         if (acpi_ec_poll_mode)
315                 return acpi_ec_poll_write(ec, address, data);
316         else
317                 return acpi_ec_intr_write(ec, address, data);
318 }
319 static int acpi_ec_poll_read(union acpi_ec *ec, u8 address, u32 * data)
320 {
321         acpi_status status = AE_OK;
322         int result = 0;
323         u32 glk = 0;
324
325
326         if (!ec || !data)
327                 return -EINVAL;
328
329         *data = 0;
330
331         if (ec->common.global_lock) {
332                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
333                 if (ACPI_FAILURE(status))
334                         return -ENODEV;
335         }
336
337         if (down_interruptible(&ec->poll.sem)) {
338                 result = -ERESTARTSYS;
339                 goto end_nosem;
340         }
341         
342         acpi_hw_low_level_write(8, ACPI_EC_COMMAND_READ,
343                                 &ec->common.command_addr);
344         result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
345         if (result)
346                 goto end;
347
348         acpi_hw_low_level_write(8, address, &ec->common.data_addr);
349         result = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF);
350         if (result)
351                 goto end;
352
353         acpi_hw_low_level_read(8, data, &ec->common.data_addr);
354
355         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Read [%02x] from address [%02x]\n",
356                           *data, address));
357
358       end:
359         up(&ec->poll.sem);
360 end_nosem:
361         if (ec->common.global_lock)
362                 acpi_release_global_lock(glk);
363
364         return result;
365 }
366
367 static int acpi_ec_poll_write(union acpi_ec *ec, u8 address, u8 data)
368 {
369         int result = 0;
370         acpi_status status = AE_OK;
371         u32 glk = 0;
372
373
374         if (!ec)
375                 return -EINVAL;
376
377         if (ec->common.global_lock) {
378                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
379                 if (ACPI_FAILURE(status))
380                         return -ENODEV;
381         }
382
383         if (down_interruptible(&ec->poll.sem)) {
384                 result = -ERESTARTSYS;
385                 goto end_nosem;
386         }
387         
388         acpi_hw_low_level_write(8, ACPI_EC_COMMAND_WRITE,
389                                 &ec->common.command_addr);
390         result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
391         if (result)
392                 goto end;
393
394         acpi_hw_low_level_write(8, address, &ec->common.data_addr);
395         result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
396         if (result)
397                 goto end;
398
399         acpi_hw_low_level_write(8, data, &ec->common.data_addr);
400         result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
401         if (result)
402                 goto end;
403
404         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Wrote [%02x] to address [%02x]\n",
405                           data, address));
406
407       end:
408         up(&ec->poll.sem);
409 end_nosem:
410         if (ec->common.global_lock)
411                 acpi_release_global_lock(glk);
412
413         return result;
414 }
415
416 static int acpi_ec_intr_read(union acpi_ec *ec, u8 address, u32 * data)
417 {
418         int status = 0;
419         u32 glk;
420
421
422         if (!ec || !data)
423                 return -EINVAL;
424
425         *data = 0;
426
427         if (ec->common.global_lock) {
428                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
429                 if (ACPI_FAILURE(status))
430                         return -ENODEV;
431         }
432
433         WARN_ON(in_interrupt());
434         down(&ec->intr.sem);
435
436         status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
437         if (status) {
438                 printk(KERN_DEBUG PREFIX "read EC, IB not empty\n");
439                 goto end;
440         }
441         acpi_hw_low_level_write(8, ACPI_EC_COMMAND_READ,
442                                 &ec->common.command_addr);
443         status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
444         if (status) {
445                 printk(KERN_DEBUG PREFIX "read EC, IB not empty\n");
446         }
447
448         acpi_hw_low_level_write(8, address, &ec->common.data_addr);
449         status = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF);
450         if (status) {
451                 printk(KERN_DEBUG PREFIX "read EC, OB not full\n");
452                 goto end;
453         }
454         acpi_hw_low_level_read(8, data, &ec->common.data_addr);
455         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Read [%02x] from address [%02x]\n",
456                           *data, address));
457
458       end:
459         up(&ec->intr.sem);
460
461         if (ec->common.global_lock)
462                 acpi_release_global_lock(glk);
463
464         return status;
465 }
466
467 static int acpi_ec_intr_write(union acpi_ec *ec, u8 address, u8 data)
468 {
469         int status = 0;
470         u32 glk;
471
472
473         if (!ec)
474                 return -EINVAL;
475
476         if (ec->common.global_lock) {
477                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
478                 if (ACPI_FAILURE(status))
479                         return -ENODEV;
480         }
481
482         WARN_ON(in_interrupt());
483         down(&ec->intr.sem);
484
485         status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
486         if (status) {
487                 printk(KERN_DEBUG PREFIX "write EC, IB not empty\n");
488         }
489         acpi_hw_low_level_write(8, ACPI_EC_COMMAND_WRITE,
490                                 &ec->common.command_addr);
491         status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
492         if (status) {
493                 printk(KERN_DEBUG PREFIX "write EC, IB not empty\n");
494         }
495
496         acpi_hw_low_level_write(8, address, &ec->common.data_addr);
497         status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
498         if (status) {
499                 printk(KERN_DEBUG PREFIX "write EC, IB not empty\n");
500         }
501
502         acpi_hw_low_level_write(8, data, &ec->common.data_addr);
503
504         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Wrote [%02x] to address [%02x]\n",
505                           data, address));
506
507         up(&ec->intr.sem);
508
509         if (ec->common.global_lock)
510                 acpi_release_global_lock(glk);
511
512         return status;
513 }
514
515 /*
516  * Externally callable EC access functions. For now, assume 1 EC only
517  */
518 int ec_read(u8 addr, u8 * val)
519 {
520         union acpi_ec *ec;
521         int err;
522         u32 temp_data;
523
524         if (!first_ec)
525                 return -ENODEV;
526
527         ec = acpi_driver_data(first_ec);
528
529         err = acpi_ec_read(ec, addr, &temp_data);
530
531         if (!err) {
532                 *val = temp_data;
533                 return 0;
534         } else
535                 return err;
536 }
537
538 EXPORT_SYMBOL(ec_read);
539
540 int ec_write(u8 addr, u8 val)
541 {
542         union acpi_ec *ec;
543         int err;
544
545         if (!first_ec)
546                 return -ENODEV;
547
548         ec = acpi_driver_data(first_ec);
549
550         err = acpi_ec_write(ec, addr, val);
551
552         return err;
553 }
554
555 EXPORT_SYMBOL(ec_write);
556
557 static int acpi_ec_query(union acpi_ec *ec, u32 * data)
558 {
559         if (acpi_ec_poll_mode)
560                 return acpi_ec_poll_query(ec, data);
561         else
562                 return acpi_ec_intr_query(ec, data);
563 }
564 static int acpi_ec_poll_query(union acpi_ec *ec, u32 * data)
565 {
566         int result = 0;
567         acpi_status status = AE_OK;
568         u32 glk = 0;
569
570
571         if (!ec || !data)
572                 return -EINVAL;
573
574         *data = 0;
575
576         if (ec->common.global_lock) {
577                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
578                 if (ACPI_FAILURE(status))
579                         return -ENODEV;
580         }
581
582         /*
583          * Query the EC to find out which _Qxx method we need to evaluate.
584          * Note that successful completion of the query causes the ACPI_EC_SCI
585          * bit to be cleared (and thus clearing the interrupt source).
586          */
587         if (down_interruptible(&ec->poll.sem)) {
588                 result = -ERESTARTSYS;
589                 goto end_nosem;
590         }
591         
592         acpi_hw_low_level_write(8, ACPI_EC_COMMAND_QUERY,
593                                 &ec->common.command_addr);
594         result = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF);
595         if (result)
596                 goto end;
597
598         acpi_hw_low_level_read(8, data, &ec->common.data_addr);
599         if (!*data)
600                 result = -ENODATA;
601
602       end:
603         up(&ec->poll.sem);
604 end_nosem:
605         if (ec->common.global_lock)
606                 acpi_release_global_lock(glk);
607
608         return result;
609 }
610 static int acpi_ec_intr_query(union acpi_ec *ec, u32 * data)
611 {
612         int status = 0;
613         u32 glk;
614
615
616         if (!ec || !data)
617                 return -EINVAL;
618         *data = 0;
619
620         if (ec->common.global_lock) {
621                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
622                 if (ACPI_FAILURE(status))
623                         return -ENODEV;
624         }
625
626         down(&ec->intr.sem);
627
628         status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
629         if (status) {
630                 printk(KERN_DEBUG PREFIX "query EC, IB not empty\n");
631                 goto end;
632         }
633         /*
634          * Query the EC to find out which _Qxx method we need to evaluate.
635          * Note that successful completion of the query causes the ACPI_EC_SCI
636          * bit to be cleared (and thus clearing the interrupt source).
637          */
638         acpi_hw_low_level_write(8, ACPI_EC_COMMAND_QUERY,
639                                 &ec->common.command_addr);
640         status = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF);
641         if (status) {
642                 printk(KERN_DEBUG PREFIX "query EC, OB not full\n");
643                 goto end;
644         }
645
646         acpi_hw_low_level_read(8, data, &ec->common.data_addr);
647         if (!*data)
648                 status = -ENODATA;
649
650       end:
651         up(&ec->intr.sem);
652
653         if (ec->common.global_lock)
654                 acpi_release_global_lock(glk);
655
656         return status;
657 }
658
659 /* --------------------------------------------------------------------------
660                                 Event Management
661    -------------------------------------------------------------------------- */
662
663 union acpi_ec_query_data {
664         acpi_handle handle;
665         u8 data;
666 };
667
668 static void acpi_ec_gpe_query(void *ec_cxt)
669 {
670         if (acpi_ec_poll_mode)
671                 acpi_ec_gpe_poll_query(ec_cxt);
672         else
673                 acpi_ec_gpe_intr_query(ec_cxt);
674 }
675
676 static void acpi_ec_gpe_poll_query(void *ec_cxt)
677 {
678         union acpi_ec *ec = (union acpi_ec *)ec_cxt;
679         u32 value = 0;
680         static char object_name[5] = { '_', 'Q', '0', '0', '\0' };
681         const char hex[] = { '0', '1', '2', '3', '4', '5', '6', '7',
682                 '8', '9', 'A', 'B', 'C', 'D', 'E', 'F'
683         };
684
685
686         if (!ec_cxt)
687                 goto end;
688
689         if (down_interruptible (&ec->poll.sem)) {
690                 return;
691         }
692         acpi_hw_low_level_read(8, &value, &ec->common.command_addr);
693         up(&ec->poll.sem);
694
695         /* TBD: Implement asynch events!
696          * NOTE: All we care about are EC-SCI's.  Other EC events are
697          * handled via polling (yuck!).  This is because some systems
698          * treat EC-SCIs as level (versus EDGE!) triggered, preventing
699          *  a purely interrupt-driven approach (grumble, grumble).
700          */
701         if (!(value & ACPI_EC_FLAG_SCI))
702                 goto end;
703
704         if (acpi_ec_query(ec, &value))
705                 goto end;
706
707         object_name[2] = hex[((value >> 4) & 0x0F)];
708         object_name[3] = hex[(value & 0x0F)];
709
710         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Evaluating %s\n", object_name));
711
712         acpi_evaluate_object(ec->common.handle, object_name, NULL, NULL);
713
714       end:
715         acpi_enable_gpe(NULL, ec->common.gpe_bit, ACPI_NOT_ISR);
716 }
717 static void acpi_ec_gpe_intr_query(void *ec_cxt)
718 {
719         union acpi_ec *ec = (union acpi_ec *)ec_cxt;
720         u32 value;
721         int result = -ENODATA;
722         static char object_name[5] = { '_', 'Q', '0', '0', '\0' };
723         const char hex[] = { '0', '1', '2', '3', '4', '5', '6', '7',
724                 '8', '9', 'A', 'B', 'C', 'D', 'E', 'F'
725         };
726
727
728         if (acpi_ec_read_status(ec) & ACPI_EC_FLAG_SCI)
729                 result = acpi_ec_query(ec, &value);
730
731         if (result)
732                 goto end;
733
734         object_name[2] = hex[((value >> 4) & 0x0F)];
735         object_name[3] = hex[(value & 0x0F)];
736
737         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Evaluating %s\n", object_name));
738
739         acpi_evaluate_object(ec->common.handle, object_name, NULL, NULL);
740       end:
741         atomic_dec(&ec->intr.pending_gpe);
742         return;
743 }
744
745 static u32 acpi_ec_gpe_handler(void *data)
746 {
747         if (acpi_ec_poll_mode)
748                 return acpi_ec_gpe_poll_handler(data);
749         else
750                 return acpi_ec_gpe_intr_handler(data);
751 }
752 static u32 acpi_ec_gpe_poll_handler(void *data)
753 {
754         acpi_status status = AE_OK;
755         union acpi_ec *ec = (union acpi_ec *)data;
756
757         if (!ec)
758                 return ACPI_INTERRUPT_NOT_HANDLED;
759
760         acpi_disable_gpe(NULL, ec->common.gpe_bit, ACPI_ISR);
761
762         status = acpi_os_execute(OSL_EC_POLL_HANDLER, acpi_ec_gpe_query, ec);
763
764         if (status == AE_OK)
765                 return ACPI_INTERRUPT_HANDLED;
766         else
767                 return ACPI_INTERRUPT_NOT_HANDLED;
768 }
769 static u32 acpi_ec_gpe_intr_handler(void *data)
770 {
771         acpi_status status = AE_OK;
772         u32 value;
773         union acpi_ec *ec = (union acpi_ec *)data;
774
775         if (!ec)
776                 return ACPI_INTERRUPT_NOT_HANDLED;
777
778         acpi_clear_gpe(NULL, ec->common.gpe_bit, ACPI_ISR);
779         value = acpi_ec_read_status(ec);
780
781         switch (ec->intr.expect_event) {
782         case ACPI_EC_EVENT_OBF:
783                 if (!(value & ACPI_EC_FLAG_OBF))
784                         break;
785                 ec->intr.expect_event = 0;
786                 wake_up(&ec->intr.wait);
787                 break;
788         case ACPI_EC_EVENT_IBE:
789                 if ((value & ACPI_EC_FLAG_IBF))
790                         break;
791                 ec->intr.expect_event = 0;
792                 wake_up(&ec->intr.wait);
793                 break;
794         default:
795                 break;
796         }
797
798         if (value & ACPI_EC_FLAG_SCI) {
799                 atomic_add(1, &ec->intr.pending_gpe);
800                 status = acpi_os_execute(OSL_EC_BURST_HANDLER,
801                                                      acpi_ec_gpe_query, ec);
802                 return status == AE_OK ?
803                     ACPI_INTERRUPT_HANDLED : ACPI_INTERRUPT_NOT_HANDLED;
804         }
805         acpi_enable_gpe(NULL, ec->common.gpe_bit, ACPI_ISR);
806         return status == AE_OK ?
807             ACPI_INTERRUPT_HANDLED : ACPI_INTERRUPT_NOT_HANDLED;
808 }
809
810 /* --------------------------------------------------------------------------
811                              Address Space Management
812    -------------------------------------------------------------------------- */
813
814 static acpi_status
815 acpi_ec_space_setup(acpi_handle region_handle,
816                     u32 function, void *handler_context, void **return_context)
817 {
818         /*
819          * The EC object is in the handler context and is needed
820          * when calling the acpi_ec_space_handler.
821          */
822         *return_context = (function != ACPI_REGION_DEACTIVATE) ?
823             handler_context : NULL;
824
825         return AE_OK;
826 }
827
828 static acpi_status
829 acpi_ec_space_handler(u32 function,
830                       acpi_physical_address address,
831                       u32 bit_width,
832                       acpi_integer * value,
833                       void *handler_context, void *region_context)
834 {
835         int result = 0;
836         union acpi_ec *ec = NULL;
837         u64 temp = *value;
838         acpi_integer f_v = 0;
839         int i = 0;
840
841
842         if ((address > 0xFF) || !value || !handler_context)
843                 return AE_BAD_PARAMETER;
844
845         if (bit_width != 8 && acpi_strict) {
846                 printk(KERN_WARNING PREFIX
847                        "acpi_ec_space_handler: bit_width should be 8\n");
848                 return AE_BAD_PARAMETER;
849         }
850
851         ec = (union acpi_ec *)handler_context;
852
853       next_byte:
854         switch (function) {
855         case ACPI_READ:
856                 temp = 0;
857                 result = acpi_ec_read(ec, (u8) address, (u32 *) & temp);
858                 break;
859         case ACPI_WRITE:
860                 result = acpi_ec_write(ec, (u8) address, (u8) temp);
861                 break;
862         default:
863                 result = -EINVAL;
864                 goto out;
865                 break;
866         }
867
868         bit_width -= 8;
869         if (bit_width) {
870                 if (function == ACPI_READ)
871                         f_v |= temp << 8 * i;
872                 if (function == ACPI_WRITE)
873                         temp >>= 8;
874                 i++;
875                 address++;
876                 goto next_byte;
877         }
878
879         if (function == ACPI_READ) {
880                 f_v |= temp << 8 * i;
881                 *value = f_v;
882         }
883
884       out:
885         switch (result) {
886         case -EINVAL:
887                 return AE_BAD_PARAMETER;
888                 break;
889         case -ENODEV:
890                 return AE_NOT_FOUND;
891                 break;
892         case -ETIME:
893                 return AE_TIME;
894                 break;
895         default:
896                 return AE_OK;
897         }
898 }
899
900 /* --------------------------------------------------------------------------
901                               FS Interface (/proc)
902    -------------------------------------------------------------------------- */
903
904 static struct proc_dir_entry *acpi_ec_dir;
905
906 static int acpi_ec_read_info(struct seq_file *seq, void *offset)
907 {
908         union acpi_ec *ec = (union acpi_ec *)seq->private;
909
910
911         if (!ec)
912                 goto end;
913
914         seq_printf(seq, "gpe bit:                 0x%02x\n",
915                    (u32) ec->common.gpe_bit);
916         seq_printf(seq, "ports:                   0x%02x, 0x%02x\n",
917                    (u32) ec->common.status_addr.address,
918                    (u32) ec->common.data_addr.address);
919         seq_printf(seq, "use global lock:         %s\n",
920                    ec->common.global_lock ? "yes" : "no");
921         acpi_enable_gpe(NULL, ec->common.gpe_bit, ACPI_NOT_ISR);
922
923       end:
924         return 0;
925 }
926
927 static int acpi_ec_info_open_fs(struct inode *inode, struct file *file)
928 {
929         return single_open(file, acpi_ec_read_info, PDE(inode)->data);
930 }
931
932 static struct file_operations acpi_ec_info_ops = {
933         .open = acpi_ec_info_open_fs,
934         .read = seq_read,
935         .llseek = seq_lseek,
936         .release = single_release,
937         .owner = THIS_MODULE,
938 };
939
940 static int acpi_ec_add_fs(struct acpi_device *device)
941 {
942         struct proc_dir_entry *entry = NULL;
943
944
945         if (!acpi_device_dir(device)) {
946                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
947                                                      acpi_ec_dir);
948                 if (!acpi_device_dir(device))
949                         return -ENODEV;
950         }
951
952         entry = create_proc_entry(ACPI_EC_FILE_INFO, S_IRUGO,
953                                   acpi_device_dir(device));
954         if (!entry)
955                 return -ENODEV;
956         else {
957                 entry->proc_fops = &acpi_ec_info_ops;
958                 entry->data = acpi_driver_data(device);
959                 entry->owner = THIS_MODULE;
960         }
961
962         return 0;
963 }
964
965 static int acpi_ec_remove_fs(struct acpi_device *device)
966 {
967
968         if (acpi_device_dir(device)) {
969                 remove_proc_entry(ACPI_EC_FILE_INFO, acpi_device_dir(device));
970                 remove_proc_entry(acpi_device_bid(device), acpi_ec_dir);
971                 acpi_device_dir(device) = NULL;
972         }
973
974         return 0;
975 }
976
977 /* --------------------------------------------------------------------------
978                                Driver Interface
979    -------------------------------------------------------------------------- */
980
981 static int acpi_ec_poll_add(struct acpi_device *device)
982 {
983         int result = 0;
984         acpi_status status = AE_OK;
985         union acpi_ec *ec = NULL;
986
987
988         if (!device)
989                 return -EINVAL;
990
991         ec = kmalloc(sizeof(union acpi_ec), GFP_KERNEL);
992         if (!ec)
993                 return -ENOMEM;
994         memset(ec, 0, sizeof(union acpi_ec));
995
996         ec->common.handle = device->handle;
997         ec->common.uid = -1;
998         init_MUTEX(&ec->poll.sem);
999         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
1000         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
1001         acpi_driver_data(device) = ec;
1002
1003         /* Use the global lock for all EC transactions? */
1004         acpi_evaluate_integer(ec->common.handle, "_GLK", NULL,
1005                               &ec->common.global_lock);
1006
1007         /* XXX we don't test uids, because on some boxes ecdt uid = 0, see:
1008            http://bugzilla.kernel.org/show_bug.cgi?id=6111 */
1009         if (ec_ecdt) {
1010                 acpi_remove_address_space_handler(ACPI_ROOT_OBJECT,
1011                                                   ACPI_ADR_SPACE_EC,
1012                                                   &acpi_ec_space_handler);
1013
1014                 acpi_remove_gpe_handler(NULL, ec_ecdt->common.gpe_bit,
1015                                         &acpi_ec_gpe_handler);
1016
1017                 kfree(ec_ecdt);
1018         }
1019
1020         /* Get GPE bit assignment (EC events). */
1021         /* TODO: Add support for _GPE returning a package */
1022         status =
1023             acpi_evaluate_integer(ec->common.handle, "_GPE", NULL,
1024                                   &ec->common.gpe_bit);
1025         if (ACPI_FAILURE(status)) {
1026                 ACPI_EXCEPTION((AE_INFO, status, "Obtaining GPE bit"));
1027                 result = -ENODEV;
1028                 goto end;
1029         }
1030
1031         result = acpi_ec_add_fs(device);
1032         if (result)
1033                 goto end;
1034
1035         printk(KERN_INFO PREFIX "%s [%s] (gpe %d) polling mode.\n",
1036                acpi_device_name(device), acpi_device_bid(device),
1037                (u32) ec->common.gpe_bit);
1038
1039         if (!first_ec)
1040                 first_ec = device;
1041
1042       end:
1043         if (result)
1044                 kfree(ec);
1045
1046         return result;
1047 }
1048 static int acpi_ec_intr_add(struct acpi_device *device)
1049 {
1050         int result = 0;
1051         acpi_status status = AE_OK;
1052         union acpi_ec *ec = NULL;
1053
1054
1055         if (!device)
1056                 return -EINVAL;
1057
1058         ec = kmalloc(sizeof(union acpi_ec), GFP_KERNEL);
1059         if (!ec)
1060                 return -ENOMEM;
1061         memset(ec, 0, sizeof(union acpi_ec));
1062
1063         ec->common.handle = device->handle;
1064         ec->common.uid = -1;
1065         atomic_set(&ec->intr.pending_gpe, 0);
1066         atomic_set(&ec->intr.leaving_burst, 1);
1067         init_MUTEX(&ec->intr.sem);
1068         init_waitqueue_head(&ec->intr.wait);
1069         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
1070         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
1071         acpi_driver_data(device) = ec;
1072
1073         /* Use the global lock for all EC transactions? */
1074         acpi_evaluate_integer(ec->common.handle, "_GLK", NULL,
1075                               &ec->common.global_lock);
1076
1077         /* XXX we don't test uids, because on some boxes ecdt uid = 0, see:
1078            http://bugzilla.kernel.org/show_bug.cgi?id=6111 */
1079         if (ec_ecdt) {
1080                 acpi_remove_address_space_handler(ACPI_ROOT_OBJECT,
1081                                                   ACPI_ADR_SPACE_EC,
1082                                                   &acpi_ec_space_handler);
1083
1084                 acpi_remove_gpe_handler(NULL, ec_ecdt->common.gpe_bit,
1085                                         &acpi_ec_gpe_handler);
1086
1087                 kfree(ec_ecdt);
1088         }
1089
1090         /* Get GPE bit assignment (EC events). */
1091         /* TODO: Add support for _GPE returning a package */
1092         status =
1093             acpi_evaluate_integer(ec->common.handle, "_GPE", NULL,
1094                                   &ec->common.gpe_bit);
1095         if (ACPI_FAILURE(status)) {
1096                 printk(KERN_ERR PREFIX "Obtaining GPE bit assignment\n");
1097                 result = -ENODEV;
1098                 goto end;
1099         }
1100
1101         result = acpi_ec_add_fs(device);
1102         if (result)
1103                 goto end;
1104
1105         printk(KERN_INFO PREFIX "%s [%s] (gpe %d) interrupt mode.\n",
1106                acpi_device_name(device), acpi_device_bid(device),
1107                (u32) ec->common.gpe_bit);
1108
1109         if (!first_ec)
1110                 first_ec = device;
1111
1112       end:
1113         if (result)
1114                 kfree(ec);
1115
1116         return result;
1117 }
1118
1119 static int acpi_ec_remove(struct acpi_device *device, int type)
1120 {
1121         union acpi_ec *ec = NULL;
1122
1123
1124         if (!device)
1125                 return -EINVAL;
1126
1127         ec = acpi_driver_data(device);
1128
1129         acpi_ec_remove_fs(device);
1130
1131         kfree(ec);
1132
1133         return 0;
1134 }
1135
1136 static acpi_status
1137 acpi_ec_io_ports(struct acpi_resource *resource, void *context)
1138 {
1139         union acpi_ec *ec = (union acpi_ec *)context;
1140         struct acpi_generic_address *addr;
1141
1142         if (resource->type != ACPI_RESOURCE_TYPE_IO) {
1143                 return AE_OK;
1144         }
1145
1146         /*
1147          * The first address region returned is the data port, and
1148          * the second address region returned is the status/command
1149          * port.
1150          */
1151         if (ec->common.data_addr.register_bit_width == 0) {
1152                 addr = &ec->common.data_addr;
1153         } else if (ec->common.command_addr.register_bit_width == 0) {
1154                 addr = &ec->common.command_addr;
1155         } else {
1156                 return AE_CTRL_TERMINATE;
1157         }
1158
1159         addr->address_space_id = ACPI_ADR_SPACE_SYSTEM_IO;
1160         addr->register_bit_width = 8;
1161         addr->register_bit_offset = 0;
1162         addr->address = resource->data.io.minimum;
1163
1164         return AE_OK;
1165 }
1166
1167 static int acpi_ec_start(struct acpi_device *device)
1168 {
1169         acpi_status status = AE_OK;
1170         union acpi_ec *ec = NULL;
1171
1172
1173         if (!device)
1174                 return -EINVAL;
1175
1176         ec = acpi_driver_data(device);
1177
1178         if (!ec)
1179                 return -EINVAL;
1180
1181         /*
1182          * Get I/O port addresses. Convert to GAS format.
1183          */
1184         status = acpi_walk_resources(ec->common.handle, METHOD_NAME__CRS,
1185                                      acpi_ec_io_ports, ec);
1186         if (ACPI_FAILURE(status)
1187             || ec->common.command_addr.register_bit_width == 0) {
1188                 printk(KERN_ERR PREFIX "Error getting I/O port addresses\n");
1189                 return -ENODEV;
1190         }
1191
1192         ec->common.status_addr = ec->common.command_addr;
1193
1194         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "gpe=0x%02x, ports=0x%2x,0x%2x\n",
1195                           (u32) ec->common.gpe_bit,
1196                           (u32) ec->common.command_addr.address,
1197                           (u32) ec->common.data_addr.address));
1198
1199         /*
1200          * Install GPE handler
1201          */
1202         status = acpi_install_gpe_handler(NULL, ec->common.gpe_bit,
1203                                           ACPI_GPE_EDGE_TRIGGERED,
1204                                           &acpi_ec_gpe_handler, ec);
1205         if (ACPI_FAILURE(status)) {
1206                 return -ENODEV;
1207         }
1208         acpi_set_gpe_type(NULL, ec->common.gpe_bit, ACPI_GPE_TYPE_RUNTIME);
1209         acpi_enable_gpe(NULL, ec->common.gpe_bit, ACPI_NOT_ISR);
1210
1211         status = acpi_install_address_space_handler(ec->common.handle,
1212                                                     ACPI_ADR_SPACE_EC,
1213                                                     &acpi_ec_space_handler,
1214                                                     &acpi_ec_space_setup, ec);
1215         if (ACPI_FAILURE(status)) {
1216                 acpi_remove_gpe_handler(NULL, ec->common.gpe_bit,
1217                                         &acpi_ec_gpe_handler);
1218                 return -ENODEV;
1219         }
1220
1221         return AE_OK;
1222 }
1223
1224 static int acpi_ec_stop(struct acpi_device *device, int type)
1225 {
1226         acpi_status status = AE_OK;
1227         union acpi_ec *ec = NULL;
1228
1229
1230         if (!device)
1231                 return -EINVAL;
1232
1233         ec = acpi_driver_data(device);
1234
1235         status = acpi_remove_address_space_handler(ec->common.handle,
1236                                                    ACPI_ADR_SPACE_EC,
1237                                                    &acpi_ec_space_handler);
1238         if (ACPI_FAILURE(status))
1239                 return -ENODEV;
1240
1241         status =
1242             acpi_remove_gpe_handler(NULL, ec->common.gpe_bit,
1243                                     &acpi_ec_gpe_handler);
1244         if (ACPI_FAILURE(status))
1245                 return -ENODEV;
1246
1247         return 0;
1248 }
1249
1250 static acpi_status __init
1251 acpi_fake_ecdt_callback(acpi_handle handle,
1252                         u32 Level, void *context, void **retval)
1253 {
1254
1255         if (acpi_ec_poll_mode)
1256                 return acpi_fake_ecdt_poll_callback(handle,
1257                                                        Level, context, retval);
1258         else
1259                 return acpi_fake_ecdt_intr_callback(handle,
1260                                                      Level, context, retval);
1261 }
1262
1263 static acpi_status __init
1264 acpi_fake_ecdt_poll_callback(acpi_handle handle,
1265                                 u32 Level, void *context, void **retval)
1266 {
1267         acpi_status status;
1268
1269         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
1270                                      acpi_ec_io_ports, ec_ecdt);
1271         if (ACPI_FAILURE(status))
1272                 return status;
1273         ec_ecdt->common.status_addr = ec_ecdt->common.command_addr;
1274
1275         ec_ecdt->common.uid = -1;
1276         acpi_evaluate_integer(handle, "_UID", NULL, &ec_ecdt->common.uid);
1277
1278         status =
1279             acpi_evaluate_integer(handle, "_GPE", NULL,
1280                                   &ec_ecdt->common.gpe_bit);
1281         if (ACPI_FAILURE(status))
1282                 return status;
1283         init_MUTEX(&ec_ecdt->poll.sem);
1284         ec_ecdt->common.global_lock = TRUE;
1285         ec_ecdt->common.handle = handle;
1286
1287         printk(KERN_INFO PREFIX "GPE=0x%02x, ports=0x%2x, 0x%2x\n",
1288                (u32) ec_ecdt->common.gpe_bit,
1289                (u32) ec_ecdt->common.command_addr.address,
1290                (u32) ec_ecdt->common.data_addr.address);
1291
1292         return AE_CTRL_TERMINATE;
1293 }
1294
1295 static acpi_status __init
1296 acpi_fake_ecdt_intr_callback(acpi_handle handle,
1297                               u32 Level, void *context, void **retval)
1298 {
1299         acpi_status status;
1300
1301         init_MUTEX(&ec_ecdt->intr.sem);
1302         init_waitqueue_head(&ec_ecdt->intr.wait);
1303         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
1304                                      acpi_ec_io_ports, ec_ecdt);
1305         if (ACPI_FAILURE(status))
1306                 return status;
1307         ec_ecdt->common.status_addr = ec_ecdt->common.command_addr;
1308
1309         ec_ecdt->common.uid = -1;
1310         acpi_evaluate_integer(handle, "_UID", NULL, &ec_ecdt->common.uid);
1311
1312         status =
1313             acpi_evaluate_integer(handle, "_GPE", NULL,
1314                                   &ec_ecdt->common.gpe_bit);
1315         if (ACPI_FAILURE(status))
1316                 return status;
1317         ec_ecdt->common.global_lock = TRUE;
1318         ec_ecdt->common.handle = handle;
1319
1320         printk(KERN_INFO PREFIX "GPE=0x%02x, ports=0x%2x, 0x%2x\n",
1321                (u32) ec_ecdt->common.gpe_bit,
1322                (u32) ec_ecdt->common.command_addr.address,
1323                (u32) ec_ecdt->common.data_addr.address);
1324
1325         return AE_CTRL_TERMINATE;
1326 }
1327
1328 /*
1329  * Some BIOS (such as some from Gateway laptops) access EC region very early
1330  * such as in BAT0._INI or EC._INI before an EC device is found and
1331  * do not provide an ECDT. According to ACPI spec, ECDT isn't mandatorily
1332  * required, but if EC regison is accessed early, it is required.
1333  * The routine tries to workaround the BIOS bug by pre-scan EC device
1334  * It assumes that _CRS, _HID, _GPE, _UID methods of EC don't touch any
1335  * op region (since _REG isn't invoked yet). The assumption is true for
1336  * all systems found.
1337  */
1338 static int __init acpi_ec_fake_ecdt(void)
1339 {
1340         acpi_status status;
1341         int ret = 0;
1342
1343         printk(KERN_INFO PREFIX "Try to make an fake ECDT\n");
1344
1345         ec_ecdt = kmalloc(sizeof(union acpi_ec), GFP_KERNEL);
1346         if (!ec_ecdt) {
1347                 ret = -ENOMEM;
1348                 goto error;
1349         }
1350         memset(ec_ecdt, 0, sizeof(union acpi_ec));
1351
1352         status = acpi_get_devices(ACPI_EC_HID,
1353                                   acpi_fake_ecdt_callback, NULL, NULL);
1354         if (ACPI_FAILURE(status)) {
1355                 kfree(ec_ecdt);
1356                 ec_ecdt = NULL;
1357                 ret = -ENODEV;
1358                 goto error;
1359         }
1360         return 0;
1361       error:
1362         printk(KERN_ERR PREFIX "Can't make an fake ECDT\n");
1363         return ret;
1364 }
1365
1366 static int __init acpi_ec_get_real_ecdt(void)
1367 {
1368         if (acpi_ec_poll_mode)
1369                 return acpi_ec_poll_get_real_ecdt();
1370         else
1371                 return acpi_ec_intr_get_real_ecdt();
1372 }
1373
1374 static int __init acpi_ec_poll_get_real_ecdt(void)
1375 {
1376         acpi_status status;
1377         struct acpi_table_ecdt *ecdt_ptr;
1378
1379         status = acpi_get_firmware_table("ECDT", 1, ACPI_LOGICAL_ADDRESSING,
1380                                          (struct acpi_table_header **)
1381                                          &ecdt_ptr);
1382         if (ACPI_FAILURE(status))
1383                 return -ENODEV;
1384
1385         printk(KERN_INFO PREFIX "Found ECDT\n");
1386
1387         /*
1388          * Generate a temporary ec context to use until the namespace is scanned
1389          */
1390         ec_ecdt = kmalloc(sizeof(union acpi_ec), GFP_KERNEL);
1391         if (!ec_ecdt)
1392                 return -ENOMEM;
1393         memset(ec_ecdt, 0, sizeof(union acpi_ec));
1394
1395         ec_ecdt->common.command_addr = ecdt_ptr->ec_control;
1396         ec_ecdt->common.status_addr = ecdt_ptr->ec_control;
1397         ec_ecdt->common.data_addr = ecdt_ptr->ec_data;
1398         ec_ecdt->common.gpe_bit = ecdt_ptr->gpe_bit;
1399         init_MUTEX(&ec_ecdt->poll.sem);
1400         /* use the GL just to be safe */
1401         ec_ecdt->common.global_lock = TRUE;
1402         ec_ecdt->common.uid = ecdt_ptr->uid;
1403
1404         status =
1405             acpi_get_handle(NULL, ecdt_ptr->ec_id, &ec_ecdt->common.handle);
1406         if (ACPI_FAILURE(status)) {
1407                 goto error;
1408         }
1409
1410         return 0;
1411       error:
1412         printk(KERN_ERR PREFIX "Could not use ECDT\n");
1413         kfree(ec_ecdt);
1414         ec_ecdt = NULL;
1415
1416         return -ENODEV;
1417 }
1418
1419 static int __init acpi_ec_intr_get_real_ecdt(void)
1420 {
1421         acpi_status status;
1422         struct acpi_table_ecdt *ecdt_ptr;
1423
1424         status = acpi_get_firmware_table("ECDT", 1, ACPI_LOGICAL_ADDRESSING,
1425                                          (struct acpi_table_header **)
1426                                          &ecdt_ptr);
1427         if (ACPI_FAILURE(status))
1428                 return -ENODEV;
1429
1430         printk(KERN_INFO PREFIX "Found ECDT\n");
1431
1432         /*
1433          * Generate a temporary ec context to use until the namespace is scanned
1434          */
1435         ec_ecdt = kmalloc(sizeof(union acpi_ec), GFP_KERNEL);
1436         if (!ec_ecdt)
1437                 return -ENOMEM;
1438         memset(ec_ecdt, 0, sizeof(union acpi_ec));
1439
1440         init_MUTEX(&ec_ecdt->intr.sem);
1441         init_waitqueue_head(&ec_ecdt->intr.wait);
1442         ec_ecdt->common.command_addr = ecdt_ptr->ec_control;
1443         ec_ecdt->common.status_addr = ecdt_ptr->ec_control;
1444         ec_ecdt->common.data_addr = ecdt_ptr->ec_data;
1445         ec_ecdt->common.gpe_bit = ecdt_ptr->gpe_bit;
1446         /* use the GL just to be safe */
1447         ec_ecdt->common.global_lock = TRUE;
1448         ec_ecdt->common.uid = ecdt_ptr->uid;
1449
1450         status =
1451             acpi_get_handle(NULL, ecdt_ptr->ec_id, &ec_ecdt->common.handle);
1452         if (ACPI_FAILURE(status)) {
1453                 goto error;
1454         }
1455
1456         return 0;
1457       error:
1458         printk(KERN_ERR PREFIX "Could not use ECDT\n");
1459         kfree(ec_ecdt);
1460         ec_ecdt = NULL;
1461
1462         return -ENODEV;
1463 }
1464
1465 static int __initdata acpi_fake_ecdt_enabled;
1466 int __init acpi_ec_ecdt_probe(void)
1467 {
1468         acpi_status status;
1469         int ret;
1470
1471         ret = acpi_ec_get_real_ecdt();
1472         /* Try to make a fake ECDT */
1473         if (ret && acpi_fake_ecdt_enabled) {
1474                 ret = acpi_ec_fake_ecdt();
1475         }
1476
1477         if (ret)
1478                 return 0;
1479
1480         /*
1481          * Install GPE handler
1482          */
1483         status = acpi_install_gpe_handler(NULL, ec_ecdt->common.gpe_bit,
1484                                           ACPI_GPE_EDGE_TRIGGERED,
1485                                           &acpi_ec_gpe_handler, ec_ecdt);
1486         if (ACPI_FAILURE(status)) {
1487                 goto error;
1488         }
1489         acpi_set_gpe_type(NULL, ec_ecdt->common.gpe_bit, ACPI_GPE_TYPE_RUNTIME);
1490         acpi_enable_gpe(NULL, ec_ecdt->common.gpe_bit, ACPI_NOT_ISR);
1491
1492         status = acpi_install_address_space_handler(ACPI_ROOT_OBJECT,
1493                                                     ACPI_ADR_SPACE_EC,
1494                                                     &acpi_ec_space_handler,
1495                                                     &acpi_ec_space_setup,
1496                                                     ec_ecdt);
1497         if (ACPI_FAILURE(status)) {
1498                 acpi_remove_gpe_handler(NULL, ec_ecdt->common.gpe_bit,
1499                                         &acpi_ec_gpe_handler);
1500                 goto error;
1501         }
1502
1503         return 0;
1504
1505       error:
1506         printk(KERN_ERR PREFIX "Could not use ECDT\n");
1507         kfree(ec_ecdt);
1508         ec_ecdt = NULL;
1509
1510         return -ENODEV;
1511 }
1512
1513 static int __init acpi_ec_init(void)
1514 {
1515         int result = 0;
1516
1517
1518         if (acpi_disabled)
1519                 return 0;
1520
1521         acpi_ec_dir = proc_mkdir(ACPI_EC_CLASS, acpi_root_dir);
1522         if (!acpi_ec_dir)
1523                 return -ENODEV;
1524
1525         /* Now register the driver for the EC */
1526         result = acpi_bus_register_driver(&acpi_ec_driver);
1527         if (result < 0) {
1528                 remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1529                 return -ENODEV;
1530         }
1531
1532         return result;
1533 }
1534
1535 subsys_initcall(acpi_ec_init);
1536
1537 /* EC driver currently not unloadable */
1538 #if 0
1539 static void __exit acpi_ec_exit(void)
1540 {
1541
1542         acpi_bus_unregister_driver(&acpi_ec_driver);
1543
1544         remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1545
1546         return;
1547 }
1548 #endif                          /* 0 */
1549
1550 static int __init acpi_fake_ecdt_setup(char *str)
1551 {
1552         acpi_fake_ecdt_enabled = 1;
1553         return 1;
1554 }
1555
1556 __setup("acpi_fake_ecdt", acpi_fake_ecdt_setup);
1557 static int __init acpi_ec_set_intr_mode(char *str)
1558 {
1559         int intr;
1560
1561         if (!get_option(&str, &intr))
1562                 return 0;
1563
1564         if (intr) {
1565                 acpi_ec_poll_mode = EC_INTR;
1566                 acpi_ec_driver.ops.add = acpi_ec_intr_add;
1567         } else {
1568                 acpi_ec_poll_mode = EC_POLL;
1569                 acpi_ec_driver.ops.add = acpi_ec_poll_add;
1570         }
1571         printk(KERN_INFO PREFIX "EC %s mode.\n", intr ? "interrupt" : "polling");
1572         return 1;
1573 }
1574
1575 __setup("ec_intr=", acpi_ec_set_intr_mode);