Pull bugzilla-5764 into release branch
[linux-2.6.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         ACPI_FUNCTION_TRACE("acpi_ec_wait");
211
212         ec->intr.expect_event = event;
213         smp_mb();
214
215         switch (event) {
216         case ACPI_EC_EVENT_IBE:
217                 if (~acpi_ec_read_status(ec) & event) {
218                         ec->intr.expect_event = 0;
219                         return_VALUE(0);
220                 }
221                 break;
222         default:
223                 break;
224         }
225
226         result = wait_event_timeout(ec->intr.wait,
227                                     !ec->intr.expect_event,
228                                     msecs_to_jiffies(ACPI_EC_DELAY));
229
230         ec->intr.expect_event = 0;
231         smp_mb();
232
233         /*
234          * Verify that the event in question has actually happened by
235          * querying EC status. Do the check even if operation timed-out
236          * to make sure that we did not miss interrupt.
237          */
238         switch (event) {
239         case ACPI_EC_EVENT_OBF:
240                 if (acpi_ec_read_status(ec) & ACPI_EC_FLAG_OBF)
241                         return_VALUE(0);
242                 break;
243
244         case ACPI_EC_EVENT_IBE:
245                 if (~acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF)
246                         return_VALUE(0);
247                 break;
248         }
249
250         return_VALUE(-ETIME);
251 }
252
253 #ifdef ACPI_FUTURE_USAGE
254 /*
255  * Note: samsung nv5000 doesn't work with ec burst mode.
256  * http://bugzilla.kernel.org/show_bug.cgi?id=4980
257  */
258 int acpi_ec_enter_burst_mode(union acpi_ec *ec)
259 {
260         u32 tmp = 0;
261         int status = 0;
262
263         ACPI_FUNCTION_TRACE("acpi_ec_enter_burst_mode");
264
265         status = acpi_ec_read_status(ec);
266         if (status != -EINVAL && !(status & ACPI_EC_FLAG_BURST)) {
267                 status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
268                 if (status)
269                         goto end;
270                 acpi_hw_low_level_write(8, ACPI_EC_BURST_ENABLE,
271                                         &ec->common.command_addr);
272                 status = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF);
273                 acpi_hw_low_level_read(8, &tmp, &ec->common.data_addr);
274                 if (tmp != 0x90) {      /* Burst ACK byte */
275                         return_VALUE(-EINVAL);
276                 }
277         }
278
279         atomic_set(&ec->intr.leaving_burst, 0);
280         return_VALUE(0);
281       end:
282         printk(KERN_WARNING PREFIX "Error in acpi_ec_wait\n");
283         return_VALUE(-1);
284 }
285
286 int acpi_ec_leave_burst_mode(union acpi_ec *ec)
287 {
288         int status = 0;
289
290         ACPI_FUNCTION_TRACE("acpi_ec_leave_burst_mode");
291
292         status = acpi_ec_read_status(ec);
293         if (status != -EINVAL && (status & ACPI_EC_FLAG_BURST)){
294                 status = acpi_ec_wait(ec, ACPI_EC_FLAG_IBF);
295                 if(status)
296                         goto end;
297                 acpi_hw_low_level_write(8, ACPI_EC_BURST_DISABLE, &ec->common.command_addr);
298                 acpi_ec_wait(ec, ACPI_EC_FLAG_IBF);
299         } 
300         atomic_set(&ec->intr.leaving_burst, 1);
301         return_VALUE(0);
302 end:
303         printk(KERN_WARNING PREFIX "leave burst_mode:error\n");
304         return_VALUE(-1);
305 }
306 #endif /* ACPI_FUTURE_USAGE */
307
308 static int acpi_ec_read(union acpi_ec *ec, u8 address, u32 * data)
309 {
310         if (acpi_ec_poll_mode)
311                 return acpi_ec_poll_read(ec, address, data);
312         else
313                 return acpi_ec_intr_read(ec, address, data);
314 }
315 static int acpi_ec_write(union acpi_ec *ec, u8 address, u8 data)
316 {
317         if (acpi_ec_poll_mode)
318                 return acpi_ec_poll_write(ec, address, data);
319         else
320                 return acpi_ec_intr_write(ec, address, data);
321 }
322 static int acpi_ec_poll_read(union acpi_ec *ec, u8 address, u32 * data)
323 {
324         acpi_status status = AE_OK;
325         int result = 0;
326         u32 glk = 0;
327
328         ACPI_FUNCTION_TRACE("acpi_ec_read");
329
330         if (!ec || !data)
331                 return_VALUE(-EINVAL);
332
333         *data = 0;
334
335         if (ec->common.global_lock) {
336                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
337                 if (ACPI_FAILURE(status))
338                         return_VALUE(-ENODEV);
339         }
340
341         if (down_interruptible(&ec->poll.sem)) {
342                 result = -ERESTARTSYS;
343                 goto end_nosem;
344         }
345         
346         acpi_hw_low_level_write(8, ACPI_EC_COMMAND_READ,
347                                 &ec->common.command_addr);
348         result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
349         if (result)
350                 goto end;
351
352         acpi_hw_low_level_write(8, address, &ec->common.data_addr);
353         result = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF);
354         if (result)
355                 goto end;
356
357         acpi_hw_low_level_read(8, data, &ec->common.data_addr);
358
359         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Read [%02x] from address [%02x]\n",
360                           *data, address));
361
362       end:
363         up(&ec->poll.sem);
364 end_nosem:
365         if (ec->common.global_lock)
366                 acpi_release_global_lock(glk);
367
368         return_VALUE(result);
369 }
370
371 static int acpi_ec_poll_write(union acpi_ec *ec, u8 address, u8 data)
372 {
373         int result = 0;
374         acpi_status status = AE_OK;
375         u32 glk = 0;
376
377         ACPI_FUNCTION_TRACE("acpi_ec_write");
378
379         if (!ec)
380                 return_VALUE(-EINVAL);
381
382         if (ec->common.global_lock) {
383                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
384                 if (ACPI_FAILURE(status))
385                         return_VALUE(-ENODEV);
386         }
387
388         if (down_interruptible(&ec->poll.sem)) {
389                 result = -ERESTARTSYS;
390                 goto end_nosem;
391         }
392         
393         acpi_hw_low_level_write(8, ACPI_EC_COMMAND_WRITE,
394                                 &ec->common.command_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, address, &ec->common.data_addr);
400         result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
401         if (result)
402                 goto end;
403
404         acpi_hw_low_level_write(8, data, &ec->common.data_addr);
405         result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
406         if (result)
407                 goto end;
408
409         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Wrote [%02x] to address [%02x]\n",
410                           data, address));
411
412       end:
413         up(&ec->poll.sem);
414 end_nosem:
415         if (ec->common.global_lock)
416                 acpi_release_global_lock(glk);
417
418         return_VALUE(result);
419 }
420
421 static int acpi_ec_intr_read(union acpi_ec *ec, u8 address, u32 * data)
422 {
423         int status = 0;
424         u32 glk;
425
426         ACPI_FUNCTION_TRACE("acpi_ec_read");
427
428         if (!ec || !data)
429                 return_VALUE(-EINVAL);
430
431         *data = 0;
432
433         if (ec->common.global_lock) {
434                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
435                 if (ACPI_FAILURE(status))
436                         return_VALUE(-ENODEV);
437         }
438
439         WARN_ON(in_interrupt());
440         down(&ec->intr.sem);
441
442         status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
443         if (status) {
444                 printk(KERN_DEBUG PREFIX "read EC, IB not empty\n");
445                 goto end;
446         }
447         acpi_hw_low_level_write(8, ACPI_EC_COMMAND_READ,
448                                 &ec->common.command_addr);
449         status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
450         if (status) {
451                 printk(KERN_DEBUG PREFIX "read EC, IB not empty\n");
452         }
453
454         acpi_hw_low_level_write(8, address, &ec->common.data_addr);
455         status = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF);
456         if (status) {
457                 printk(KERN_DEBUG PREFIX "read EC, OB not full\n");
458                 goto end;
459         }
460         acpi_hw_low_level_read(8, data, &ec->common.data_addr);
461         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Read [%02x] from address [%02x]\n",
462                           *data, address));
463
464       end:
465         up(&ec->intr.sem);
466
467         if (ec->common.global_lock)
468                 acpi_release_global_lock(glk);
469
470         return_VALUE(status);
471 }
472
473 static int acpi_ec_intr_write(union acpi_ec *ec, u8 address, u8 data)
474 {
475         int status = 0;
476         u32 glk;
477
478         ACPI_FUNCTION_TRACE("acpi_ec_write");
479
480         if (!ec)
481                 return_VALUE(-EINVAL);
482
483         if (ec->common.global_lock) {
484                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
485                 if (ACPI_FAILURE(status))
486                         return_VALUE(-ENODEV);
487         }
488
489         WARN_ON(in_interrupt());
490         down(&ec->intr.sem);
491
492         status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
493         if (status) {
494                 printk(KERN_DEBUG PREFIX "write EC, IB not empty\n");
495         }
496         acpi_hw_low_level_write(8, ACPI_EC_COMMAND_WRITE,
497                                 &ec->common.command_addr);
498         status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
499         if (status) {
500                 printk(KERN_DEBUG PREFIX "write EC, IB not empty\n");
501         }
502
503         acpi_hw_low_level_write(8, address, &ec->common.data_addr);
504         status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
505         if (status) {
506                 printk(KERN_DEBUG PREFIX "write EC, IB not empty\n");
507         }
508
509         acpi_hw_low_level_write(8, data, &ec->common.data_addr);
510
511         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Wrote [%02x] to address [%02x]\n",
512                           data, address));
513
514         up(&ec->intr.sem);
515
516         if (ec->common.global_lock)
517                 acpi_release_global_lock(glk);
518
519         return_VALUE(status);
520 }
521
522 /*
523  * Externally callable EC access functions. For now, assume 1 EC only
524  */
525 int ec_read(u8 addr, u8 * val)
526 {
527         union acpi_ec *ec;
528         int err;
529         u32 temp_data;
530
531         if (!first_ec)
532                 return -ENODEV;
533
534         ec = acpi_driver_data(first_ec);
535
536         err = acpi_ec_read(ec, addr, &temp_data);
537
538         if (!err) {
539                 *val = temp_data;
540                 return 0;
541         } else
542                 return err;
543 }
544
545 EXPORT_SYMBOL(ec_read);
546
547 int ec_write(u8 addr, u8 val)
548 {
549         union acpi_ec *ec;
550         int err;
551
552         if (!first_ec)
553                 return -ENODEV;
554
555         ec = acpi_driver_data(first_ec);
556
557         err = acpi_ec_write(ec, addr, val);
558
559         return err;
560 }
561
562 EXPORT_SYMBOL(ec_write);
563
564 static int acpi_ec_query(union acpi_ec *ec, u32 * data)
565 {
566         if (acpi_ec_poll_mode)
567                 return acpi_ec_poll_query(ec, data);
568         else
569                 return acpi_ec_intr_query(ec, data);
570 }
571 static int acpi_ec_poll_query(union acpi_ec *ec, u32 * data)
572 {
573         int result = 0;
574         acpi_status status = AE_OK;
575         u32 glk = 0;
576
577         ACPI_FUNCTION_TRACE("acpi_ec_query");
578
579         if (!ec || !data)
580                 return_VALUE(-EINVAL);
581
582         *data = 0;
583
584         if (ec->common.global_lock) {
585                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
586                 if (ACPI_FAILURE(status))
587                         return_VALUE(-ENODEV);
588         }
589
590         /*
591          * Query the EC to find out which _Qxx method we need to evaluate.
592          * Note that successful completion of the query causes the ACPI_EC_SCI
593          * bit to be cleared (and thus clearing the interrupt source).
594          */
595         if (down_interruptible(&ec->poll.sem)) {
596                 result = -ERESTARTSYS;
597                 goto end_nosem;
598         }
599         
600         acpi_hw_low_level_write(8, ACPI_EC_COMMAND_QUERY,
601                                 &ec->common.command_addr);
602         result = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF);
603         if (result)
604                 goto end;
605
606         acpi_hw_low_level_read(8, data, &ec->common.data_addr);
607         if (!*data)
608                 result = -ENODATA;
609
610       end:
611         up(&ec->poll.sem);
612 end_nosem:
613         if (ec->common.global_lock)
614                 acpi_release_global_lock(glk);
615
616         return_VALUE(result);
617 }
618 static int acpi_ec_intr_query(union acpi_ec *ec, u32 * data)
619 {
620         int status = 0;
621         u32 glk;
622
623         ACPI_FUNCTION_TRACE("acpi_ec_query");
624
625         if (!ec || !data)
626                 return_VALUE(-EINVAL);
627         *data = 0;
628
629         if (ec->common.global_lock) {
630                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
631                 if (ACPI_FAILURE(status))
632                         return_VALUE(-ENODEV);
633         }
634
635         down(&ec->intr.sem);
636
637         status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
638         if (status) {
639                 printk(KERN_DEBUG PREFIX "query EC, IB not empty\n");
640                 goto end;
641         }
642         /*
643          * Query the EC to find out which _Qxx method we need to evaluate.
644          * Note that successful completion of the query causes the ACPI_EC_SCI
645          * bit to be cleared (and thus clearing the interrupt source).
646          */
647         acpi_hw_low_level_write(8, ACPI_EC_COMMAND_QUERY,
648                                 &ec->common.command_addr);
649         status = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF);
650         if (status) {
651                 printk(KERN_DEBUG PREFIX "query EC, OB not full\n");
652                 goto end;
653         }
654
655         acpi_hw_low_level_read(8, data, &ec->common.data_addr);
656         if (!*data)
657                 status = -ENODATA;
658
659       end:
660         up(&ec->intr.sem);
661
662         if (ec->common.global_lock)
663                 acpi_release_global_lock(glk);
664
665         return_VALUE(status);
666 }
667
668 /* --------------------------------------------------------------------------
669                                 Event Management
670    -------------------------------------------------------------------------- */
671
672 union acpi_ec_query_data {
673         acpi_handle handle;
674         u8 data;
675 };
676
677 static void acpi_ec_gpe_query(void *ec_cxt)
678 {
679         if (acpi_ec_poll_mode)
680                 acpi_ec_gpe_poll_query(ec_cxt);
681         else
682                 acpi_ec_gpe_intr_query(ec_cxt);
683 }
684
685 static void acpi_ec_gpe_poll_query(void *ec_cxt)
686 {
687         union acpi_ec *ec = (union acpi_ec *)ec_cxt;
688         u32 value = 0;
689         static char object_name[5] = { '_', 'Q', '0', '0', '\0' };
690         const char hex[] = { '0', '1', '2', '3', '4', '5', '6', '7',
691                 '8', '9', 'A', 'B', 'C', 'D', 'E', 'F'
692         };
693
694         ACPI_FUNCTION_TRACE("acpi_ec_gpe_query");
695
696         if (!ec_cxt)
697                 goto end;
698
699         if (down_interruptible (&ec->poll.sem)) {
700                 return_VOID;
701         }
702         acpi_hw_low_level_read(8, &value, &ec->common.command_addr);
703         up(&ec->poll.sem);
704
705         /* TBD: Implement asynch events!
706          * NOTE: All we care about are EC-SCI's.  Other EC events are
707          * handled via polling (yuck!).  This is because some systems
708          * treat EC-SCIs as level (versus EDGE!) triggered, preventing
709          *  a purely interrupt-driven approach (grumble, grumble).
710          */
711         if (!(value & ACPI_EC_FLAG_SCI))
712                 goto end;
713
714         if (acpi_ec_query(ec, &value))
715                 goto end;
716
717         object_name[2] = hex[((value >> 4) & 0x0F)];
718         object_name[3] = hex[(value & 0x0F)];
719
720         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Evaluating %s\n", object_name));
721
722         acpi_evaluate_object(ec->common.handle, object_name, NULL, NULL);
723
724       end:
725         acpi_enable_gpe(NULL, ec->common.gpe_bit, ACPI_NOT_ISR);
726 }
727 static void acpi_ec_gpe_intr_query(void *ec_cxt)
728 {
729         union acpi_ec *ec = (union acpi_ec *)ec_cxt;
730         u32 value;
731         int result = -ENODATA;
732         static char object_name[5] = { '_', 'Q', '0', '0', '\0' };
733         const char hex[] = { '0', '1', '2', '3', '4', '5', '6', '7',
734                 '8', '9', 'A', 'B', 'C', 'D', 'E', 'F'
735         };
736
737         ACPI_FUNCTION_TRACE("acpi_ec_gpe_query");
738
739         if (acpi_ec_read_status(ec) & ACPI_EC_FLAG_SCI)
740                 result = acpi_ec_query(ec, &value);
741
742         if (result)
743                 goto end;
744
745         object_name[2] = hex[((value >> 4) & 0x0F)];
746         object_name[3] = hex[(value & 0x0F)];
747
748         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Evaluating %s\n", object_name));
749
750         acpi_evaluate_object(ec->common.handle, object_name, NULL, NULL);
751       end:
752         atomic_dec(&ec->intr.pending_gpe);
753         return;
754 }
755
756 static u32 acpi_ec_gpe_handler(void *data)
757 {
758         if (acpi_ec_poll_mode)
759                 return acpi_ec_gpe_poll_handler(data);
760         else
761                 return acpi_ec_gpe_intr_handler(data);
762 }
763 static u32 acpi_ec_gpe_poll_handler(void *data)
764 {
765         acpi_status status = AE_OK;
766         union acpi_ec *ec = (union acpi_ec *)data;
767
768         if (!ec)
769                 return ACPI_INTERRUPT_NOT_HANDLED;
770
771         acpi_disable_gpe(NULL, ec->common.gpe_bit, ACPI_ISR);
772
773         status = acpi_os_execute(OSL_EC_POLL_HANDLER, acpi_ec_gpe_query, ec);
774
775         if (status == AE_OK)
776                 return ACPI_INTERRUPT_HANDLED;
777         else
778                 return ACPI_INTERRUPT_NOT_HANDLED;
779 }
780 static u32 acpi_ec_gpe_intr_handler(void *data)
781 {
782         acpi_status status = AE_OK;
783         u32 value;
784         union acpi_ec *ec = (union acpi_ec *)data;
785
786         if (!ec)
787                 return ACPI_INTERRUPT_NOT_HANDLED;
788
789         acpi_clear_gpe(NULL, ec->common.gpe_bit, ACPI_ISR);
790         value = acpi_ec_read_status(ec);
791
792         switch (ec->intr.expect_event) {
793         case ACPI_EC_EVENT_OBF:
794                 if (!(value & ACPI_EC_FLAG_OBF))
795                         break;
796         case ACPI_EC_EVENT_IBE:
797                 if ((value & ACPI_EC_FLAG_IBF))
798                         break;
799                 ec->intr.expect_event = 0;
800                 wake_up(&ec->intr.wait);
801                 return ACPI_INTERRUPT_HANDLED;
802         default:
803                 break;
804         }
805
806         if (value & ACPI_EC_FLAG_SCI) {
807                 atomic_add(1, &ec->intr.pending_gpe);
808                 status = acpi_os_execute(OSL_EC_BURST_HANDLER,
809                                                      acpi_ec_gpe_query, ec);
810                 return status == AE_OK ?
811                     ACPI_INTERRUPT_HANDLED : ACPI_INTERRUPT_NOT_HANDLED;
812         }
813         acpi_enable_gpe(NULL, ec->common.gpe_bit, ACPI_ISR);
814         return status == AE_OK ?
815             ACPI_INTERRUPT_HANDLED : ACPI_INTERRUPT_NOT_HANDLED;
816 }
817
818 /* --------------------------------------------------------------------------
819                              Address Space Management
820    -------------------------------------------------------------------------- */
821
822 static acpi_status
823 acpi_ec_space_setup(acpi_handle region_handle,
824                     u32 function, void *handler_context, void **return_context)
825 {
826         /*
827          * The EC object is in the handler context and is needed
828          * when calling the acpi_ec_space_handler.
829          */
830         *return_context = (function != ACPI_REGION_DEACTIVATE) ?
831             handler_context : NULL;
832
833         return AE_OK;
834 }
835
836 static acpi_status
837 acpi_ec_space_handler(u32 function,
838                       acpi_physical_address address,
839                       u32 bit_width,
840                       acpi_integer * value,
841                       void *handler_context, void *region_context)
842 {
843         int result = 0;
844         union acpi_ec *ec = NULL;
845         u64 temp = *value;
846         acpi_integer f_v = 0;
847         int i = 0;
848
849         ACPI_FUNCTION_TRACE("acpi_ec_space_handler");
850
851         if ((address > 0xFF) || !value || !handler_context)
852                 return_VALUE(AE_BAD_PARAMETER);
853
854         if (bit_width != 8 && acpi_strict) {
855                 printk(KERN_WARNING PREFIX
856                        "acpi_ec_space_handler: bit_width should be 8\n");
857                 return_VALUE(AE_BAD_PARAMETER);
858         }
859
860         ec = (union acpi_ec *)handler_context;
861
862       next_byte:
863         switch (function) {
864         case ACPI_READ:
865                 temp = 0;
866                 result = acpi_ec_read(ec, (u8) address, (u32 *) & temp);
867                 break;
868         case ACPI_WRITE:
869                 result = acpi_ec_write(ec, (u8) address, (u8) temp);
870                 break;
871         default:
872                 result = -EINVAL;
873                 goto out;
874                 break;
875         }
876
877         bit_width -= 8;
878         if (bit_width) {
879                 if (function == ACPI_READ)
880                         f_v |= temp << 8 * i;
881                 if (function == ACPI_WRITE)
882                         temp >>= 8;
883                 i++;
884                 address++;
885                 goto next_byte;
886         }
887
888         if (function == ACPI_READ) {
889                 f_v |= temp << 8 * i;
890                 *value = f_v;
891         }
892
893       out:
894         switch (result) {
895         case -EINVAL:
896                 return_VALUE(AE_BAD_PARAMETER);
897                 break;
898         case -ENODEV:
899                 return_VALUE(AE_NOT_FOUND);
900                 break;
901         case -ETIME:
902                 return_VALUE(AE_TIME);
903                 break;
904         default:
905                 return_VALUE(AE_OK);
906         }
907 }
908
909 /* --------------------------------------------------------------------------
910                               FS Interface (/proc)
911    -------------------------------------------------------------------------- */
912
913 static struct proc_dir_entry *acpi_ec_dir;
914
915 static int acpi_ec_read_info(struct seq_file *seq, void *offset)
916 {
917         union acpi_ec *ec = (union acpi_ec *)seq->private;
918
919         ACPI_FUNCTION_TRACE("acpi_ec_read_info");
920
921         if (!ec)
922                 goto end;
923
924         seq_printf(seq, "gpe bit:                 0x%02x\n",
925                    (u32) ec->common.gpe_bit);
926         seq_printf(seq, "ports:                   0x%02x, 0x%02x\n",
927                    (u32) ec->common.status_addr.address,
928                    (u32) ec->common.data_addr.address);
929         seq_printf(seq, "use global lock:         %s\n",
930                    ec->common.global_lock ? "yes" : "no");
931         acpi_enable_gpe(NULL, ec->common.gpe_bit, ACPI_NOT_ISR);
932
933       end:
934         return_VALUE(0);
935 }
936
937 static int acpi_ec_info_open_fs(struct inode *inode, struct file *file)
938 {
939         return single_open(file, acpi_ec_read_info, PDE(inode)->data);
940 }
941
942 static struct file_operations acpi_ec_info_ops = {
943         .open = acpi_ec_info_open_fs,
944         .read = seq_read,
945         .llseek = seq_lseek,
946         .release = single_release,
947         .owner = THIS_MODULE,
948 };
949
950 static int acpi_ec_add_fs(struct acpi_device *device)
951 {
952         struct proc_dir_entry *entry = NULL;
953
954         ACPI_FUNCTION_TRACE("acpi_ec_add_fs");
955
956         if (!acpi_device_dir(device)) {
957                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
958                                                      acpi_ec_dir);
959                 if (!acpi_device_dir(device))
960                         return_VALUE(-ENODEV);
961         }
962
963         entry = create_proc_entry(ACPI_EC_FILE_INFO, S_IRUGO,
964                                   acpi_device_dir(device));
965         if (!entry)
966                 ACPI_DEBUG_PRINT((ACPI_DB_WARN,
967                                   "Unable to create '%s' fs entry\n",
968                                   ACPI_EC_FILE_INFO));
969         else {
970                 entry->proc_fops = &acpi_ec_info_ops;
971                 entry->data = acpi_driver_data(device);
972                 entry->owner = THIS_MODULE;
973         }
974
975         return_VALUE(0);
976 }
977
978 static int acpi_ec_remove_fs(struct acpi_device *device)
979 {
980         ACPI_FUNCTION_TRACE("acpi_ec_remove_fs");
981
982         if (acpi_device_dir(device)) {
983                 remove_proc_entry(ACPI_EC_FILE_INFO, acpi_device_dir(device));
984                 remove_proc_entry(acpi_device_bid(device), acpi_ec_dir);
985                 acpi_device_dir(device) = NULL;
986         }
987
988         return_VALUE(0);
989 }
990
991 /* --------------------------------------------------------------------------
992                                Driver Interface
993    -------------------------------------------------------------------------- */
994
995 static int acpi_ec_poll_add(struct acpi_device *device)
996 {
997         int result = 0;
998         acpi_status status = AE_OK;
999         union acpi_ec *ec = NULL;
1000
1001         ACPI_FUNCTION_TRACE("acpi_ec_add");
1002
1003         if (!device)
1004                 return_VALUE(-EINVAL);
1005
1006         ec = kmalloc(sizeof(union acpi_ec), GFP_KERNEL);
1007         if (!ec)
1008                 return_VALUE(-ENOMEM);
1009         memset(ec, 0, sizeof(union acpi_ec));
1010
1011         ec->common.handle = device->handle;
1012         ec->common.uid = -1;
1013         init_MUTEX(&ec->poll.sem);
1014         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
1015         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
1016         acpi_driver_data(device) = ec;
1017
1018         /* Use the global lock for all EC transactions? */
1019         acpi_evaluate_integer(ec->common.handle, "_GLK", NULL,
1020                               &ec->common.global_lock);
1021
1022         /* XXX we don't test uids, because on some boxes ecdt uid = 0, see:
1023            http://bugzilla.kernel.org/show_bug.cgi?id=6111 */
1024         if (ec_ecdt) {
1025                 acpi_remove_address_space_handler(ACPI_ROOT_OBJECT,
1026                                                   ACPI_ADR_SPACE_EC,
1027                                                   &acpi_ec_space_handler);
1028
1029                 acpi_remove_gpe_handler(NULL, ec_ecdt->common.gpe_bit,
1030                                         &acpi_ec_gpe_handler);
1031
1032                 kfree(ec_ecdt);
1033         }
1034
1035         /* Get GPE bit assignment (EC events). */
1036         /* TODO: Add support for _GPE returning a package */
1037         status =
1038             acpi_evaluate_integer(ec->common.handle, "_GPE", NULL,
1039                                   &ec->common.gpe_bit);
1040         if (ACPI_FAILURE(status)) {
1041                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
1042                                   "Error obtaining GPE bit assignment\n"));
1043                 result = -ENODEV;
1044                 goto end;
1045         }
1046
1047         result = acpi_ec_add_fs(device);
1048         if (result)
1049                 goto end;
1050
1051         printk(KERN_INFO PREFIX "%s [%s] (gpe %d) polling mode.\n",
1052                acpi_device_name(device), acpi_device_bid(device),
1053                (u32) ec->common.gpe_bit);
1054
1055         if (!first_ec)
1056                 first_ec = device;
1057
1058       end:
1059         if (result)
1060                 kfree(ec);
1061
1062         return_VALUE(result);
1063 }
1064 static int acpi_ec_intr_add(struct acpi_device *device)
1065 {
1066         int result = 0;
1067         acpi_status status = AE_OK;
1068         union acpi_ec *ec = NULL;
1069
1070         ACPI_FUNCTION_TRACE("acpi_ec_add");
1071
1072         if (!device)
1073                 return_VALUE(-EINVAL);
1074
1075         ec = kmalloc(sizeof(union acpi_ec), GFP_KERNEL);
1076         if (!ec)
1077                 return_VALUE(-ENOMEM);
1078         memset(ec, 0, sizeof(union acpi_ec));
1079
1080         ec->common.handle = device->handle;
1081         ec->common.uid = -1;
1082         atomic_set(&ec->intr.pending_gpe, 0);
1083         atomic_set(&ec->intr.leaving_burst, 1);
1084         init_MUTEX(&ec->intr.sem);
1085         init_waitqueue_head(&ec->intr.wait);
1086         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
1087         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
1088         acpi_driver_data(device) = ec;
1089
1090         /* Use the global lock for all EC transactions? */
1091         acpi_evaluate_integer(ec->common.handle, "_GLK", NULL,
1092                               &ec->common.global_lock);
1093
1094         /* XXX we don't test uids, because on some boxes ecdt uid = 0, see:
1095            http://bugzilla.kernel.org/show_bug.cgi?id=6111 */
1096         if (ec_ecdt) {
1097                 acpi_remove_address_space_handler(ACPI_ROOT_OBJECT,
1098                                                   ACPI_ADR_SPACE_EC,
1099                                                   &acpi_ec_space_handler);
1100
1101                 acpi_remove_gpe_handler(NULL, ec_ecdt->common.gpe_bit,
1102                                         &acpi_ec_gpe_handler);
1103
1104                 kfree(ec_ecdt);
1105         }
1106
1107         /* Get GPE bit assignment (EC events). */
1108         /* TODO: Add support for _GPE returning a package */
1109         status =
1110             acpi_evaluate_integer(ec->common.handle, "_GPE", NULL,
1111                                   &ec->common.gpe_bit);
1112         if (ACPI_FAILURE(status)) {
1113                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
1114                                   "Error obtaining GPE bit assignment\n"));
1115                 result = -ENODEV;
1116                 goto end;
1117         }
1118
1119         result = acpi_ec_add_fs(device);
1120         if (result)
1121                 goto end;
1122
1123         printk(KERN_INFO PREFIX "%s [%s] (gpe %d) interrupt mode.\n",
1124                acpi_device_name(device), acpi_device_bid(device),
1125                (u32) ec->common.gpe_bit);
1126
1127         if (!first_ec)
1128                 first_ec = device;
1129
1130       end:
1131         if (result)
1132                 kfree(ec);
1133
1134         return_VALUE(result);
1135 }
1136
1137 static int acpi_ec_remove(struct acpi_device *device, int type)
1138 {
1139         union acpi_ec *ec = NULL;
1140
1141         ACPI_FUNCTION_TRACE("acpi_ec_remove");
1142
1143         if (!device)
1144                 return_VALUE(-EINVAL);
1145
1146         ec = acpi_driver_data(device);
1147
1148         acpi_ec_remove_fs(device);
1149
1150         kfree(ec);
1151
1152         return_VALUE(0);
1153 }
1154
1155 static acpi_status
1156 acpi_ec_io_ports(struct acpi_resource *resource, void *context)
1157 {
1158         union acpi_ec *ec = (union acpi_ec *)context;
1159         struct acpi_generic_address *addr;
1160
1161         if (resource->type != ACPI_RESOURCE_TYPE_IO) {
1162                 return AE_OK;
1163         }
1164
1165         /*
1166          * The first address region returned is the data port, and
1167          * the second address region returned is the status/command
1168          * port.
1169          */
1170         if (ec->common.data_addr.register_bit_width == 0) {
1171                 addr = &ec->common.data_addr;
1172         } else if (ec->common.command_addr.register_bit_width == 0) {
1173                 addr = &ec->common.command_addr;
1174         } else {
1175                 return AE_CTRL_TERMINATE;
1176         }
1177
1178         addr->address_space_id = ACPI_ADR_SPACE_SYSTEM_IO;
1179         addr->register_bit_width = 8;
1180         addr->register_bit_offset = 0;
1181         addr->address = resource->data.io.minimum;
1182
1183         return AE_OK;
1184 }
1185
1186 static int acpi_ec_start(struct acpi_device *device)
1187 {
1188         acpi_status status = AE_OK;
1189         union acpi_ec *ec = NULL;
1190
1191         ACPI_FUNCTION_TRACE("acpi_ec_start");
1192
1193         if (!device)
1194                 return_VALUE(-EINVAL);
1195
1196         ec = acpi_driver_data(device);
1197
1198         if (!ec)
1199                 return_VALUE(-EINVAL);
1200
1201         /*
1202          * Get I/O port addresses. Convert to GAS format.
1203          */
1204         status = acpi_walk_resources(ec->common.handle, METHOD_NAME__CRS,
1205                                      acpi_ec_io_ports, ec);
1206         if (ACPI_FAILURE(status)
1207             || ec->common.command_addr.register_bit_width == 0) {
1208                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
1209                                   "Error getting I/O port addresses"));
1210                 return_VALUE(-ENODEV);
1211         }
1212
1213         ec->common.status_addr = ec->common.command_addr;
1214
1215         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "gpe=0x%02x, ports=0x%2x,0x%2x\n",
1216                           (u32) ec->common.gpe_bit,
1217                           (u32) ec->common.command_addr.address,
1218                           (u32) ec->common.data_addr.address));
1219
1220         /*
1221          * Install GPE handler
1222          */
1223         status = acpi_install_gpe_handler(NULL, ec->common.gpe_bit,
1224                                           ACPI_GPE_EDGE_TRIGGERED,
1225                                           &acpi_ec_gpe_handler, ec);
1226         if (ACPI_FAILURE(status)) {
1227                 return_VALUE(-ENODEV);
1228         }
1229         acpi_set_gpe_type(NULL, ec->common.gpe_bit, ACPI_GPE_TYPE_RUNTIME);
1230         acpi_enable_gpe(NULL, ec->common.gpe_bit, ACPI_NOT_ISR);
1231
1232         status = acpi_install_address_space_handler(ec->common.handle,
1233                                                     ACPI_ADR_SPACE_EC,
1234                                                     &acpi_ec_space_handler,
1235                                                     &acpi_ec_space_setup, ec);
1236         if (ACPI_FAILURE(status)) {
1237                 acpi_remove_gpe_handler(NULL, ec->common.gpe_bit,
1238                                         &acpi_ec_gpe_handler);
1239                 return_VALUE(-ENODEV);
1240         }
1241
1242         return_VALUE(AE_OK);
1243 }
1244
1245 static int acpi_ec_stop(struct acpi_device *device, int type)
1246 {
1247         acpi_status status = AE_OK;
1248         union acpi_ec *ec = NULL;
1249
1250         ACPI_FUNCTION_TRACE("acpi_ec_stop");
1251
1252         if (!device)
1253                 return_VALUE(-EINVAL);
1254
1255         ec = acpi_driver_data(device);
1256
1257         status = acpi_remove_address_space_handler(ec->common.handle,
1258                                                    ACPI_ADR_SPACE_EC,
1259                                                    &acpi_ec_space_handler);
1260         if (ACPI_FAILURE(status))
1261                 return_VALUE(-ENODEV);
1262
1263         status =
1264             acpi_remove_gpe_handler(NULL, ec->common.gpe_bit,
1265                                     &acpi_ec_gpe_handler);
1266         if (ACPI_FAILURE(status))
1267                 return_VALUE(-ENODEV);
1268
1269         return_VALUE(0);
1270 }
1271
1272 static acpi_status __init
1273 acpi_fake_ecdt_callback(acpi_handle handle,
1274                         u32 Level, void *context, void **retval)
1275 {
1276
1277         if (acpi_ec_poll_mode)
1278                 return acpi_fake_ecdt_poll_callback(handle,
1279                                                        Level, context, retval);
1280         else
1281                 return acpi_fake_ecdt_intr_callback(handle,
1282                                                      Level, context, retval);
1283 }
1284
1285 static acpi_status __init
1286 acpi_fake_ecdt_poll_callback(acpi_handle handle,
1287                                 u32 Level, void *context, void **retval)
1288 {
1289         acpi_status status;
1290
1291         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
1292                                      acpi_ec_io_ports, ec_ecdt);
1293         if (ACPI_FAILURE(status))
1294                 return status;
1295         ec_ecdt->common.status_addr = ec_ecdt->common.command_addr;
1296
1297         ec_ecdt->common.uid = -1;
1298         acpi_evaluate_integer(handle, "_UID", NULL, &ec_ecdt->common.uid);
1299
1300         status =
1301             acpi_evaluate_integer(handle, "_GPE", NULL,
1302                                   &ec_ecdt->common.gpe_bit);
1303         if (ACPI_FAILURE(status))
1304                 return status;
1305         init_MUTEX(&ec_ecdt->poll.sem);
1306         ec_ecdt->common.global_lock = TRUE;
1307         ec_ecdt->common.handle = handle;
1308
1309         printk(KERN_INFO PREFIX "GPE=0x%02x, ports=0x%2x, 0x%2x\n",
1310                (u32) ec_ecdt->common.gpe_bit,
1311                (u32) ec_ecdt->common.command_addr.address,
1312                (u32) ec_ecdt->common.data_addr.address);
1313
1314         return AE_CTRL_TERMINATE;
1315 }
1316
1317 static acpi_status __init
1318 acpi_fake_ecdt_intr_callback(acpi_handle handle,
1319                               u32 Level, void *context, void **retval)
1320 {
1321         acpi_status status;
1322
1323         init_MUTEX(&ec_ecdt->intr.sem);
1324         init_waitqueue_head(&ec_ecdt->intr.wait);
1325         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
1326                                      acpi_ec_io_ports, ec_ecdt);
1327         if (ACPI_FAILURE(status))
1328                 return status;
1329         ec_ecdt->common.status_addr = ec_ecdt->common.command_addr;
1330
1331         ec_ecdt->common.uid = -1;
1332         acpi_evaluate_integer(handle, "_UID", NULL, &ec_ecdt->common.uid);
1333
1334         status =
1335             acpi_evaluate_integer(handle, "_GPE", NULL,
1336                                   &ec_ecdt->common.gpe_bit);
1337         if (ACPI_FAILURE(status))
1338                 return status;
1339         ec_ecdt->common.global_lock = TRUE;
1340         ec_ecdt->common.handle = handle;
1341
1342         printk(KERN_INFO PREFIX "GPE=0x%02x, ports=0x%2x, 0x%2x\n",
1343                (u32) ec_ecdt->common.gpe_bit,
1344                (u32) ec_ecdt->common.command_addr.address,
1345                (u32) ec_ecdt->common.data_addr.address);
1346
1347         return AE_CTRL_TERMINATE;
1348 }
1349
1350 /*
1351  * Some BIOS (such as some from Gateway laptops) access EC region very early
1352  * such as in BAT0._INI or EC._INI before an EC device is found and
1353  * do not provide an ECDT. According to ACPI spec, ECDT isn't mandatorily
1354  * required, but if EC regison is accessed early, it is required.
1355  * The routine tries to workaround the BIOS bug by pre-scan EC device
1356  * It assumes that _CRS, _HID, _GPE, _UID methods of EC don't touch any
1357  * op region (since _REG isn't invoked yet). The assumption is true for
1358  * all systems found.
1359  */
1360 static int __init acpi_ec_fake_ecdt(void)
1361 {
1362         acpi_status status;
1363         int ret = 0;
1364
1365         printk(KERN_INFO PREFIX "Try to make an fake ECDT\n");
1366
1367         ec_ecdt = kmalloc(sizeof(union acpi_ec), GFP_KERNEL);
1368         if (!ec_ecdt) {
1369                 ret = -ENOMEM;
1370                 goto error;
1371         }
1372         memset(ec_ecdt, 0, sizeof(union acpi_ec));
1373
1374         status = acpi_get_devices(ACPI_EC_HID,
1375                                   acpi_fake_ecdt_callback, NULL, NULL);
1376         if (ACPI_FAILURE(status)) {
1377                 kfree(ec_ecdt);
1378                 ec_ecdt = NULL;
1379                 ret = -ENODEV;
1380                 goto error;
1381         }
1382         return 0;
1383       error:
1384         printk(KERN_ERR PREFIX "Can't make an fake ECDT\n");
1385         return ret;
1386 }
1387
1388 static int __init acpi_ec_get_real_ecdt(void)
1389 {
1390         if (acpi_ec_poll_mode)
1391                 return acpi_ec_poll_get_real_ecdt();
1392         else
1393                 return acpi_ec_intr_get_real_ecdt();
1394 }
1395
1396 static int __init acpi_ec_poll_get_real_ecdt(void)
1397 {
1398         acpi_status status;
1399         struct acpi_table_ecdt *ecdt_ptr;
1400
1401         status = acpi_get_firmware_table("ECDT", 1, ACPI_LOGICAL_ADDRESSING,
1402                                          (struct acpi_table_header **)
1403                                          &ecdt_ptr);
1404         if (ACPI_FAILURE(status))
1405                 return -ENODEV;
1406
1407         printk(KERN_INFO PREFIX "Found ECDT\n");
1408
1409         /*
1410          * Generate a temporary ec context to use until the namespace is scanned
1411          */
1412         ec_ecdt = kmalloc(sizeof(union acpi_ec), GFP_KERNEL);
1413         if (!ec_ecdt)
1414                 return -ENOMEM;
1415         memset(ec_ecdt, 0, sizeof(union acpi_ec));
1416
1417         ec_ecdt->common.command_addr = ecdt_ptr->ec_control;
1418         ec_ecdt->common.status_addr = ecdt_ptr->ec_control;
1419         ec_ecdt->common.data_addr = ecdt_ptr->ec_data;
1420         ec_ecdt->common.gpe_bit = ecdt_ptr->gpe_bit;
1421         init_MUTEX(&ec_ecdt->poll.sem);
1422         /* use the GL just to be safe */
1423         ec_ecdt->common.global_lock = TRUE;
1424         ec_ecdt->common.uid = ecdt_ptr->uid;
1425
1426         status =
1427             acpi_get_handle(NULL, ecdt_ptr->ec_id, &ec_ecdt->common.handle);
1428         if (ACPI_FAILURE(status)) {
1429                 goto error;
1430         }
1431
1432         return 0;
1433       error:
1434         printk(KERN_ERR PREFIX "Could not use ECDT\n");
1435         kfree(ec_ecdt);
1436         ec_ecdt = NULL;
1437
1438         return -ENODEV;
1439 }
1440
1441 static int __init acpi_ec_intr_get_real_ecdt(void)
1442 {
1443         acpi_status status;
1444         struct acpi_table_ecdt *ecdt_ptr;
1445
1446         status = acpi_get_firmware_table("ECDT", 1, ACPI_LOGICAL_ADDRESSING,
1447                                          (struct acpi_table_header **)
1448                                          &ecdt_ptr);
1449         if (ACPI_FAILURE(status))
1450                 return -ENODEV;
1451
1452         printk(KERN_INFO PREFIX "Found ECDT\n");
1453
1454         /*
1455          * Generate a temporary ec context to use until the namespace is scanned
1456          */
1457         ec_ecdt = kmalloc(sizeof(union acpi_ec), GFP_KERNEL);
1458         if (!ec_ecdt)
1459                 return -ENOMEM;
1460         memset(ec_ecdt, 0, sizeof(union acpi_ec));
1461
1462         init_MUTEX(&ec_ecdt->intr.sem);
1463         init_waitqueue_head(&ec_ecdt->intr.wait);
1464         ec_ecdt->common.command_addr = ecdt_ptr->ec_control;
1465         ec_ecdt->common.status_addr = ecdt_ptr->ec_control;
1466         ec_ecdt->common.data_addr = ecdt_ptr->ec_data;
1467         ec_ecdt->common.gpe_bit = ecdt_ptr->gpe_bit;
1468         /* use the GL just to be safe */
1469         ec_ecdt->common.global_lock = TRUE;
1470         ec_ecdt->common.uid = ecdt_ptr->uid;
1471
1472         status =
1473             acpi_get_handle(NULL, ecdt_ptr->ec_id, &ec_ecdt->common.handle);
1474         if (ACPI_FAILURE(status)) {
1475                 goto error;
1476         }
1477
1478         return 0;
1479       error:
1480         printk(KERN_ERR PREFIX "Could not use ECDT\n");
1481         kfree(ec_ecdt);
1482         ec_ecdt = NULL;
1483
1484         return -ENODEV;
1485 }
1486
1487 static int __initdata acpi_fake_ecdt_enabled;
1488 int __init acpi_ec_ecdt_probe(void)
1489 {
1490         acpi_status status;
1491         int ret;
1492
1493         ret = acpi_ec_get_real_ecdt();
1494         /* Try to make a fake ECDT */
1495         if (ret && acpi_fake_ecdt_enabled) {
1496                 ret = acpi_ec_fake_ecdt();
1497         }
1498
1499         if (ret)
1500                 return 0;
1501
1502         /*
1503          * Install GPE handler
1504          */
1505         status = acpi_install_gpe_handler(NULL, ec_ecdt->common.gpe_bit,
1506                                           ACPI_GPE_EDGE_TRIGGERED,
1507                                           &acpi_ec_gpe_handler, ec_ecdt);
1508         if (ACPI_FAILURE(status)) {
1509                 goto error;
1510         }
1511         acpi_set_gpe_type(NULL, ec_ecdt->common.gpe_bit, ACPI_GPE_TYPE_RUNTIME);
1512         acpi_enable_gpe(NULL, ec_ecdt->common.gpe_bit, ACPI_NOT_ISR);
1513
1514         status = acpi_install_address_space_handler(ACPI_ROOT_OBJECT,
1515                                                     ACPI_ADR_SPACE_EC,
1516                                                     &acpi_ec_space_handler,
1517                                                     &acpi_ec_space_setup,
1518                                                     ec_ecdt);
1519         if (ACPI_FAILURE(status)) {
1520                 acpi_remove_gpe_handler(NULL, ec_ecdt->common.gpe_bit,
1521                                         &acpi_ec_gpe_handler);
1522                 goto error;
1523         }
1524
1525         return 0;
1526
1527       error:
1528         printk(KERN_ERR PREFIX "Could not use ECDT\n");
1529         kfree(ec_ecdt);
1530         ec_ecdt = NULL;
1531
1532         return -ENODEV;
1533 }
1534
1535 static int __init acpi_ec_init(void)
1536 {
1537         int result = 0;
1538
1539         ACPI_FUNCTION_TRACE("acpi_ec_init");
1540
1541         if (acpi_disabled)
1542                 return_VALUE(0);
1543
1544         acpi_ec_dir = proc_mkdir(ACPI_EC_CLASS, acpi_root_dir);
1545         if (!acpi_ec_dir)
1546                 return_VALUE(-ENODEV);
1547
1548         /* Now register the driver for the EC */
1549         result = acpi_bus_register_driver(&acpi_ec_driver);
1550         if (result < 0) {
1551                 remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1552                 return_VALUE(-ENODEV);
1553         }
1554
1555         return_VALUE(result);
1556 }
1557
1558 subsys_initcall(acpi_ec_init);
1559
1560 /* EC driver currently not unloadable */
1561 #if 0
1562 static void __exit acpi_ec_exit(void)
1563 {
1564         ACPI_FUNCTION_TRACE("acpi_ec_exit");
1565
1566         acpi_bus_unregister_driver(&acpi_ec_driver);
1567
1568         remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1569
1570         return_VOID;
1571 }
1572 #endif                          /* 0 */
1573
1574 static int __init acpi_fake_ecdt_setup(char *str)
1575 {
1576         acpi_fake_ecdt_enabled = 1;
1577         return 1;
1578 }
1579
1580 __setup("acpi_fake_ecdt", acpi_fake_ecdt_setup);
1581 static int __init acpi_ec_set_intr_mode(char *str)
1582 {
1583         int intr;
1584
1585         if (!get_option(&str, &intr))
1586                 return 0;
1587
1588         if (intr) {
1589                 acpi_ec_poll_mode = EC_INTR;
1590                 acpi_ec_driver.ops.add = acpi_ec_intr_add;
1591         } else {
1592                 acpi_ec_poll_mode = EC_POLL;
1593                 acpi_ec_driver.ops.add = acpi_ec_poll_add;
1594         }
1595         printk(KERN_INFO PREFIX "EC %s mode.\n", intr ? "interrupt" : "polling");
1596         return 1;
1597 }
1598
1599 __setup("ec_intr=", acpi_ec_set_intr_mode);