Merge master.kernel.org:/home/rmk/linux-2.6-mmc
[linux-2.6] / 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_POLLING              0xFF
64 #define EC_BURST                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_burst_add(struct acpi_device *device);
69 static int acpi_ec_polling_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_polling_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         } burst;
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                 spinlock_t lock;
120         } polling;
121 };
122
123 static int acpi_ec_polling_wait(union acpi_ec *ec, u8 event);
124 static int acpi_ec_burst_wait(union acpi_ec *ec, unsigned int event);
125 static int acpi_ec_polling_read(union acpi_ec *ec, u8 address, u32 * data);
126 static int acpi_ec_burst_read(union acpi_ec *ec, u8 address, u32 * data);
127 static int acpi_ec_polling_write(union acpi_ec *ec, u8 address, u8 data);
128 static int acpi_ec_burst_write(union acpi_ec *ec, u8 address, u8 data);
129 static int acpi_ec_polling_query(union acpi_ec *ec, u32 * data);
130 static int acpi_ec_burst_query(union acpi_ec *ec, u32 * data);
131 static void acpi_ec_gpe_polling_query(void *ec_cxt);
132 static void acpi_ec_gpe_burst_query(void *ec_cxt);
133 static u32 acpi_ec_gpe_polling_handler(void *data);
134 static u32 acpi_ec_gpe_burst_handler(void *data);
135 static acpi_status __init
136 acpi_fake_ecdt_polling_callback(acpi_handle handle,
137                                 u32 Level, void *context, void **retval);
138
139 static acpi_status __init
140 acpi_fake_ecdt_burst_callback(acpi_handle handle,
141                               u32 Level, void *context, void **retval);
142
143 static int __init acpi_ec_polling_get_real_ecdt(void);
144 static int __init acpi_ec_burst_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_polling_mode = EC_POLLING;
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_polling_mode)
167                 return acpi_ec_polling_wait(ec, event);
168         else
169                 return acpi_ec_burst_wait(ec, event);
170 }
171
172 static int acpi_ec_polling_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_burst_wait(union acpi_ec *ec, unsigned int event)
207 {
208         int result = 0;
209
210         ACPI_FUNCTION_TRACE("acpi_ec_wait");
211
212         ec->burst.expect_event = event;
213         smp_mb();
214
215         switch (event) {
216         case ACPI_EC_EVENT_OBF:
217                 if (acpi_ec_read_status(ec) & event) {
218                         ec->burst.expect_event = 0;
219                         return_VALUE(0);
220                 }
221                 break;
222
223         case ACPI_EC_EVENT_IBE:
224                 if (~acpi_ec_read_status(ec) & event) {
225                         ec->burst.expect_event = 0;
226                         return_VALUE(0);
227                 }
228                 break;
229         }
230
231         result = wait_event_timeout(ec->burst.wait,
232                                     !ec->burst.expect_event,
233                                     msecs_to_jiffies(ACPI_EC_DELAY));
234
235         ec->burst.expect_event = 0;
236         smp_mb();
237
238         /*
239          * Verify that the event in question has actually happened by
240          * querying EC status. Do the check even if operation timed-out
241          * to make sure that we did not miss interrupt.
242          */
243         switch (event) {
244         case ACPI_EC_EVENT_OBF:
245                 if (acpi_ec_read_status(ec) & ACPI_EC_FLAG_OBF)
246                         return_VALUE(0);
247                 break;
248
249         case ACPI_EC_EVENT_IBE:
250                 if (~acpi_ec_read_status(ec) & ACPI_EC_FLAG_IBF)
251                         return_VALUE(0);
252                 break;
253         }
254
255         return_VALUE(-ETIME);
256 }
257
258 static 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                 if (status)
274                         return_VALUE(-EINVAL);
275                 acpi_hw_low_level_read(8, &tmp, &ec->common.data_addr);
276                 if (tmp != 0x90) {      /* Burst ACK byte */
277                         return_VALUE(-EINVAL);
278                 }
279         }
280
281         atomic_set(&ec->burst.leaving_burst, 0);
282         return_VALUE(0);
283       end:
284         printk("Error in acpi_ec_wait\n");
285         return_VALUE(-1);
286 }
287
288 static int acpi_ec_leave_burst_mode(union acpi_ec *ec)
289 {
290
291         ACPI_FUNCTION_TRACE("acpi_ec_leave_burst_mode");
292
293         atomic_set(&ec->burst.leaving_burst, 1);
294         return_VALUE(0);
295 }
296
297 static int acpi_ec_read(union acpi_ec *ec, u8 address, u32 * data)
298 {
299         if (acpi_ec_polling_mode)
300                 return acpi_ec_polling_read(ec, address, data);
301         else
302                 return acpi_ec_burst_read(ec, address, data);
303 }
304 static int acpi_ec_write(union acpi_ec *ec, u8 address, u8 data)
305 {
306         if (acpi_ec_polling_mode)
307                 return acpi_ec_polling_write(ec, address, data);
308         else
309                 return acpi_ec_burst_write(ec, address, data);
310 }
311 static int acpi_ec_polling_read(union acpi_ec *ec, u8 address, u32 * data)
312 {
313         acpi_status status = AE_OK;
314         int result = 0;
315         unsigned long flags = 0;
316         u32 glk = 0;
317
318         ACPI_FUNCTION_TRACE("acpi_ec_read");
319
320         if (!ec || !data)
321                 return_VALUE(-EINVAL);
322
323         *data = 0;
324
325         if (ec->common.global_lock) {
326                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
327                 if (ACPI_FAILURE(status))
328                         return_VALUE(-ENODEV);
329         }
330
331         spin_lock_irqsave(&ec->polling.lock, flags);
332
333         acpi_hw_low_level_write(8, ACPI_EC_COMMAND_READ,
334                                 &ec->common.command_addr);
335         result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
336         if (result)
337                 goto end;
338
339         acpi_hw_low_level_write(8, address, &ec->common.data_addr);
340         result = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF);
341         if (result)
342                 goto end;
343
344         acpi_hw_low_level_read(8, data, &ec->common.data_addr);
345
346         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Read [%02x] from address [%02x]\n",
347                           *data, address));
348
349       end:
350         spin_unlock_irqrestore(&ec->polling.lock, flags);
351
352         if (ec->common.global_lock)
353                 acpi_release_global_lock(glk);
354
355         return_VALUE(result);
356 }
357
358 static int acpi_ec_polling_write(union acpi_ec *ec, u8 address, u8 data)
359 {
360         int result = 0;
361         acpi_status status = AE_OK;
362         unsigned long flags = 0;
363         u32 glk = 0;
364
365         ACPI_FUNCTION_TRACE("acpi_ec_write");
366
367         if (!ec)
368                 return_VALUE(-EINVAL);
369
370         if (ec->common.global_lock) {
371                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
372                 if (ACPI_FAILURE(status))
373                         return_VALUE(-ENODEV);
374         }
375
376         spin_lock_irqsave(&ec->polling.lock, flags);
377
378         acpi_hw_low_level_write(8, ACPI_EC_COMMAND_WRITE,
379                                 &ec->common.command_addr);
380         result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
381         if (result)
382                 goto end;
383
384         acpi_hw_low_level_write(8, address, &ec->common.data_addr);
385         result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
386         if (result)
387                 goto end;
388
389         acpi_hw_low_level_write(8, data, &ec->common.data_addr);
390         result = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
391         if (result)
392                 goto end;
393
394         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Wrote [%02x] to address [%02x]\n",
395                           data, address));
396
397       end:
398         spin_unlock_irqrestore(&ec->polling.lock, flags);
399
400         if (ec->common.global_lock)
401                 acpi_release_global_lock(glk);
402
403         return_VALUE(result);
404 }
405
406 static int acpi_ec_burst_read(union acpi_ec *ec, u8 address, u32 * data)
407 {
408         int status = 0;
409         u32 glk;
410
411         ACPI_FUNCTION_TRACE("acpi_ec_read");
412
413         if (!ec || !data)
414                 return_VALUE(-EINVAL);
415
416         *data = 0;
417
418         if (ec->common.global_lock) {
419                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
420                 if (ACPI_FAILURE(status))
421                         return_VALUE(-ENODEV);
422         }
423
424         WARN_ON(in_interrupt());
425         down(&ec->burst.sem);
426
427         acpi_ec_enter_burst_mode(ec);
428         status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
429         if (status) {
430                 printk("read EC, IB not empty\n");
431                 goto end;
432         }
433         acpi_hw_low_level_write(8, ACPI_EC_COMMAND_READ,
434                                 &ec->common.command_addr);
435         status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
436         if (status) {
437                 printk("read EC, IB not empty\n");
438         }
439
440         acpi_hw_low_level_write(8, address, &ec->common.data_addr);
441         status = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF);
442         if (status) {
443                 printk("read EC, OB not full\n");
444                 goto end;
445         }
446         acpi_hw_low_level_read(8, data, &ec->common.data_addr);
447         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Read [%02x] from address [%02x]\n",
448                           *data, address));
449
450       end:
451         acpi_ec_leave_burst_mode(ec);
452         up(&ec->burst.sem);
453
454         if (ec->common.global_lock)
455                 acpi_release_global_lock(glk);
456
457         return_VALUE(status);
458 }
459
460 static int acpi_ec_burst_write(union acpi_ec *ec, u8 address, u8 data)
461 {
462         int status = 0;
463         u32 glk;
464
465         ACPI_FUNCTION_TRACE("acpi_ec_write");
466
467         if (!ec)
468                 return_VALUE(-EINVAL);
469
470         if (ec->common.global_lock) {
471                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
472                 if (ACPI_FAILURE(status))
473                         return_VALUE(-ENODEV);
474         }
475
476         WARN_ON(in_interrupt());
477         down(&ec->burst.sem);
478
479         acpi_ec_enter_burst_mode(ec);
480
481         status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
482         if (status) {
483                 printk("write EC, IB not empty\n");
484         }
485         acpi_hw_low_level_write(8, ACPI_EC_COMMAND_WRITE,
486                                 &ec->common.command_addr);
487         status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
488         if (status) {
489                 printk("write EC, IB not empty\n");
490         }
491
492         acpi_hw_low_level_write(8, address, &ec->common.data_addr);
493         status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
494         if (status) {
495                 printk("write EC, IB not empty\n");
496         }
497
498         acpi_hw_low_level_write(8, data, &ec->common.data_addr);
499
500         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Wrote [%02x] to address [%02x]\n",
501                           data, address));
502
503         acpi_ec_leave_burst_mode(ec);
504         up(&ec->burst.sem);
505
506         if (ec->common.global_lock)
507                 acpi_release_global_lock(glk);
508
509         return_VALUE(status);
510 }
511
512 /*
513  * Externally callable EC access functions. For now, assume 1 EC only
514  */
515 int ec_read(u8 addr, u8 * val)
516 {
517         union acpi_ec *ec;
518         int err;
519         u32 temp_data;
520
521         if (!first_ec)
522                 return -ENODEV;
523
524         ec = acpi_driver_data(first_ec);
525
526         err = acpi_ec_read(ec, addr, &temp_data);
527
528         if (!err) {
529                 *val = temp_data;
530                 return 0;
531         } else
532                 return err;
533 }
534
535 EXPORT_SYMBOL(ec_read);
536
537 int ec_write(u8 addr, u8 val)
538 {
539         union acpi_ec *ec;
540         int err;
541
542         if (!first_ec)
543                 return -ENODEV;
544
545         ec = acpi_driver_data(first_ec);
546
547         err = acpi_ec_write(ec, addr, val);
548
549         return err;
550 }
551
552 EXPORT_SYMBOL(ec_write);
553
554 static int acpi_ec_query(union acpi_ec *ec, u32 * data)
555 {
556         if (acpi_ec_polling_mode)
557                 return acpi_ec_polling_query(ec, data);
558         else
559                 return acpi_ec_burst_query(ec, data);
560 }
561 static int acpi_ec_polling_query(union acpi_ec *ec, u32 * data)
562 {
563         int result = 0;
564         acpi_status status = AE_OK;
565         unsigned long flags = 0;
566         u32 glk = 0;
567
568         ACPI_FUNCTION_TRACE("acpi_ec_query");
569
570         if (!ec || !data)
571                 return_VALUE(-EINVAL);
572
573         *data = 0;
574
575         if (ec->common.global_lock) {
576                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
577                 if (ACPI_FAILURE(status))
578                         return_VALUE(-ENODEV);
579         }
580
581         /*
582          * Query the EC to find out which _Qxx method we need to evaluate.
583          * Note that successful completion of the query causes the ACPI_EC_SCI
584          * bit to be cleared (and thus clearing the interrupt source).
585          */
586         spin_lock_irqsave(&ec->polling.lock, flags);
587
588         acpi_hw_low_level_write(8, ACPI_EC_COMMAND_QUERY,
589                                 &ec->common.command_addr);
590         result = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF);
591         if (result)
592                 goto end;
593
594         acpi_hw_low_level_read(8, data, &ec->common.data_addr);
595         if (!*data)
596                 result = -ENODATA;
597
598       end:
599         spin_unlock_irqrestore(&ec->polling.lock, flags);
600
601         if (ec->common.global_lock)
602                 acpi_release_global_lock(glk);
603
604         return_VALUE(result);
605 }
606 static int acpi_ec_burst_query(union acpi_ec *ec, u32 * data)
607 {
608         int status = 0;
609         u32 glk;
610
611         ACPI_FUNCTION_TRACE("acpi_ec_query");
612
613         if (!ec || !data)
614                 return_VALUE(-EINVAL);
615         *data = 0;
616
617         if (ec->common.global_lock) {
618                 status = acpi_acquire_global_lock(ACPI_EC_UDELAY_GLK, &glk);
619                 if (ACPI_FAILURE(status))
620                         return_VALUE(-ENODEV);
621         }
622
623         down(&ec->burst.sem);
624
625         status = acpi_ec_wait(ec, ACPI_EC_EVENT_IBE);
626         if (status) {
627                 printk("query EC, IB not empty\n");
628                 goto end;
629         }
630         /*
631          * Query the EC to find out which _Qxx method we need to evaluate.
632          * Note that successful completion of the query causes the ACPI_EC_SCI
633          * bit to be cleared (and thus clearing the interrupt source).
634          */
635         acpi_hw_low_level_write(8, ACPI_EC_COMMAND_QUERY,
636                                 &ec->common.command_addr);
637         status = acpi_ec_wait(ec, ACPI_EC_EVENT_OBF);
638         if (status) {
639                 printk("query EC, OB not full\n");
640                 goto end;
641         }
642
643         acpi_hw_low_level_read(8, data, &ec->common.data_addr);
644         if (!*data)
645                 status = -ENODATA;
646
647       end:
648         up(&ec->burst.sem);
649
650         if (ec->common.global_lock)
651                 acpi_release_global_lock(glk);
652
653         return_VALUE(status);
654 }
655
656 /* --------------------------------------------------------------------------
657                                 Event Management
658    -------------------------------------------------------------------------- */
659
660 union acpi_ec_query_data {
661         acpi_handle handle;
662         u8 data;
663 };
664
665 static void acpi_ec_gpe_query(void *ec_cxt)
666 {
667         if (acpi_ec_polling_mode)
668                 acpi_ec_gpe_polling_query(ec_cxt);
669         else
670                 acpi_ec_gpe_burst_query(ec_cxt);
671 }
672
673 static void acpi_ec_gpe_polling_query(void *ec_cxt)
674 {
675         union acpi_ec *ec = (union acpi_ec *)ec_cxt;
676         u32 value = 0;
677         unsigned long flags = 0;
678         static char object_name[5] = { '_', 'Q', '0', '0', '\0' };
679         const char hex[] = { '0', '1', '2', '3', '4', '5', '6', '7',
680                 '8', '9', 'A', 'B', 'C', 'D', 'E', 'F'
681         };
682
683         ACPI_FUNCTION_TRACE("acpi_ec_gpe_query");
684
685         if (!ec_cxt)
686                 goto end;
687
688         spin_lock_irqsave(&ec->polling.lock, flags);
689         acpi_hw_low_level_read(8, &value, &ec->common.command_addr);
690         spin_unlock_irqrestore(&ec->polling.lock, flags);
691
692         /* TBD: Implement asynch events!
693          * NOTE: All we care about are EC-SCI's.  Other EC events are
694          * handled via polling (yuck!).  This is because some systems
695          * treat EC-SCIs as level (versus EDGE!) triggered, preventing
696          *  a purely interrupt-driven approach (grumble, grumble).
697          */
698         if (!(value & ACPI_EC_FLAG_SCI))
699                 goto end;
700
701         if (acpi_ec_query(ec, &value))
702                 goto end;
703
704         object_name[2] = hex[((value >> 4) & 0x0F)];
705         object_name[3] = hex[(value & 0x0F)];
706
707         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Evaluating %s\n", object_name));
708
709         acpi_evaluate_object(ec->common.handle, object_name, NULL, NULL);
710
711       end:
712         acpi_enable_gpe(NULL, ec->common.gpe_bit, ACPI_NOT_ISR);
713 }
714 static void acpi_ec_gpe_burst_query(void *ec_cxt)
715 {
716         union acpi_ec *ec = (union acpi_ec *)ec_cxt;
717         u32 value;
718         int result = -ENODATA;
719         static char object_name[5] = { '_', 'Q', '0', '0', '\0' };
720         const char hex[] = { '0', '1', '2', '3', '4', '5', '6', '7',
721                 '8', '9', 'A', 'B', 'C', 'D', 'E', 'F'
722         };
723
724         ACPI_FUNCTION_TRACE("acpi_ec_gpe_query");
725
726         if (acpi_ec_read_status(ec) & ACPI_EC_FLAG_SCI)
727                 result = acpi_ec_query(ec, &value);
728
729         if (result)
730                 goto end;
731
732         object_name[2] = hex[((value >> 4) & 0x0F)];
733         object_name[3] = hex[(value & 0x0F)];
734
735         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Evaluating %s\n", object_name));
736
737         acpi_evaluate_object(ec->common.handle, object_name, NULL, NULL);
738       end:
739         atomic_dec(&ec->burst.pending_gpe);
740         return;
741 }
742
743 static u32 acpi_ec_gpe_handler(void *data)
744 {
745         if (acpi_ec_polling_mode)
746                 return acpi_ec_gpe_polling_handler(data);
747         else
748                 return acpi_ec_gpe_burst_handler(data);
749 }
750 static u32 acpi_ec_gpe_polling_handler(void *data)
751 {
752         acpi_status status = AE_OK;
753         union acpi_ec *ec = (union acpi_ec *)data;
754
755         if (!ec)
756                 return ACPI_INTERRUPT_NOT_HANDLED;
757
758         acpi_disable_gpe(NULL, ec->common.gpe_bit, ACPI_ISR);
759
760         status = acpi_os_queue_for_execution(OSD_PRIORITY_GPE,
761                                              acpi_ec_gpe_query, ec);
762
763         if (status == AE_OK)
764                 return ACPI_INTERRUPT_HANDLED;
765         else
766                 return ACPI_INTERRUPT_NOT_HANDLED;
767 }
768 static u32 acpi_ec_gpe_burst_handler(void *data)
769 {
770         acpi_status status = AE_OK;
771         u32 value;
772         union acpi_ec *ec = (union acpi_ec *)data;
773
774         if (!ec)
775                 return ACPI_INTERRUPT_NOT_HANDLED;
776
777         acpi_clear_gpe(NULL, ec->common.gpe_bit, ACPI_ISR);
778         value = acpi_ec_read_status(ec);
779
780         switch (ec->burst.expect_event) {
781         case ACPI_EC_EVENT_OBF:
782                 if (!(value & ACPI_EC_FLAG_OBF))
783                         break;
784         case ACPI_EC_EVENT_IBE:
785                 if ((value & ACPI_EC_FLAG_IBF))
786                         break;
787                 ec->burst.expect_event = 0;
788                 wake_up(&ec->burst.wait);
789                 return ACPI_INTERRUPT_HANDLED;
790         default:
791                 break;
792         }
793
794         if (value & ACPI_EC_FLAG_SCI) {
795                 atomic_add(1, &ec->burst.pending_gpe);
796                 status = acpi_os_queue_for_execution(OSD_PRIORITY_GPE,
797                                                      acpi_ec_gpe_query, ec);
798                 return status == AE_OK ?
799                     ACPI_INTERRUPT_HANDLED : ACPI_INTERRUPT_NOT_HANDLED;
800         }
801         acpi_enable_gpe(NULL, ec->common.gpe_bit, ACPI_ISR);
802         return status == AE_OK ?
803             ACPI_INTERRUPT_HANDLED : ACPI_INTERRUPT_NOT_HANDLED;
804 }
805
806 /* --------------------------------------------------------------------------
807                              Address Space Management
808    -------------------------------------------------------------------------- */
809
810 static acpi_status
811 acpi_ec_space_setup(acpi_handle region_handle,
812                     u32 function, void *handler_context, void **return_context)
813 {
814         /*
815          * The EC object is in the handler context and is needed
816          * when calling the acpi_ec_space_handler.
817          */
818         *return_context = (function != ACPI_REGION_DEACTIVATE) ?
819             handler_context : NULL;
820
821         return AE_OK;
822 }
823
824 static acpi_status
825 acpi_ec_space_handler(u32 function,
826                       acpi_physical_address address,
827                       u32 bit_width,
828                       acpi_integer * value,
829                       void *handler_context, void *region_context)
830 {
831         int result = 0;
832         union acpi_ec *ec = NULL;
833         u64 temp = *value;
834         acpi_integer f_v = 0;
835         int i = 0;
836
837         ACPI_FUNCTION_TRACE("acpi_ec_space_handler");
838
839         if ((address > 0xFF) || !value || !handler_context)
840                 return_VALUE(AE_BAD_PARAMETER);
841
842         if (bit_width != 8 && acpi_strict) {
843                 printk(KERN_WARNING PREFIX
844                        "acpi_ec_space_handler: bit_width should be 8\n");
845                 return_VALUE(AE_BAD_PARAMETER);
846         }
847
848         ec = (union acpi_ec *)handler_context;
849
850       next_byte:
851         switch (function) {
852         case ACPI_READ:
853                 temp = 0;
854                 result = acpi_ec_read(ec, (u8) address, (u32 *) & temp);
855                 break;
856         case ACPI_WRITE:
857                 result = acpi_ec_write(ec, (u8) address, (u8) temp);
858                 break;
859         default:
860                 result = -EINVAL;
861                 goto out;
862                 break;
863         }
864
865         bit_width -= 8;
866         if (bit_width) {
867                 if (function == ACPI_READ)
868                         f_v |= temp << 8 * i;
869                 if (function == ACPI_WRITE)
870                         temp >>= 8;
871                 i++;
872                 address++;
873                 goto next_byte;
874         }
875
876         if (function == ACPI_READ) {
877                 f_v |= temp << 8 * i;
878                 *value = f_v;
879         }
880
881       out:
882         switch (result) {
883         case -EINVAL:
884                 return_VALUE(AE_BAD_PARAMETER);
885                 break;
886         case -ENODEV:
887                 return_VALUE(AE_NOT_FOUND);
888                 break;
889         case -ETIME:
890                 return_VALUE(AE_TIME);
891                 break;
892         default:
893                 return_VALUE(AE_OK);
894         }
895 }
896
897 /* --------------------------------------------------------------------------
898                               FS Interface (/proc)
899    -------------------------------------------------------------------------- */
900
901 static struct proc_dir_entry *acpi_ec_dir;
902
903 static int acpi_ec_read_info(struct seq_file *seq, void *offset)
904 {
905         union acpi_ec *ec = (union acpi_ec *)seq->private;
906
907         ACPI_FUNCTION_TRACE("acpi_ec_read_info");
908
909         if (!ec)
910                 goto end;
911
912         seq_printf(seq, "gpe bit:                 0x%02x\n",
913                    (u32) ec->common.gpe_bit);
914         seq_printf(seq, "ports:                   0x%02x, 0x%02x\n",
915                    (u32) ec->common.status_addr.address,
916                    (u32) ec->common.data_addr.address);
917         seq_printf(seq, "use global lock:         %s\n",
918                    ec->common.global_lock ? "yes" : "no");
919         acpi_enable_gpe(NULL, ec->common.gpe_bit, ACPI_NOT_ISR);
920
921       end:
922         return_VALUE(0);
923 }
924
925 static int acpi_ec_info_open_fs(struct inode *inode, struct file *file)
926 {
927         return single_open(file, acpi_ec_read_info, PDE(inode)->data);
928 }
929
930 static struct file_operations acpi_ec_info_ops = {
931         .open = acpi_ec_info_open_fs,
932         .read = seq_read,
933         .llseek = seq_lseek,
934         .release = single_release,
935         .owner = THIS_MODULE,
936 };
937
938 static int acpi_ec_add_fs(struct acpi_device *device)
939 {
940         struct proc_dir_entry *entry = NULL;
941
942         ACPI_FUNCTION_TRACE("acpi_ec_add_fs");
943
944         if (!acpi_device_dir(device)) {
945                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
946                                                      acpi_ec_dir);
947                 if (!acpi_device_dir(device))
948                         return_VALUE(-ENODEV);
949         }
950
951         entry = create_proc_entry(ACPI_EC_FILE_INFO, S_IRUGO,
952                                   acpi_device_dir(device));
953         if (!entry)
954                 ACPI_DEBUG_PRINT((ACPI_DB_WARN,
955                                   "Unable to create '%s' fs entry\n",
956                                   ACPI_EC_FILE_INFO));
957         else {
958                 entry->proc_fops = &acpi_ec_info_ops;
959                 entry->data = acpi_driver_data(device);
960                 entry->owner = THIS_MODULE;
961         }
962
963         return_VALUE(0);
964 }
965
966 static int acpi_ec_remove_fs(struct acpi_device *device)
967 {
968         ACPI_FUNCTION_TRACE("acpi_ec_remove_fs");
969
970         if (acpi_device_dir(device)) {
971                 remove_proc_entry(ACPI_EC_FILE_INFO, acpi_device_dir(device));
972                 remove_proc_entry(acpi_device_bid(device), acpi_ec_dir);
973                 acpi_device_dir(device) = NULL;
974         }
975
976         return_VALUE(0);
977 }
978
979 /* --------------------------------------------------------------------------
980                                Driver Interface
981    -------------------------------------------------------------------------- */
982
983 static int acpi_ec_polling_add(struct acpi_device *device)
984 {
985         int result = 0;
986         acpi_status status = AE_OK;
987         union acpi_ec *ec = NULL;
988         unsigned long uid;
989
990         ACPI_FUNCTION_TRACE("acpi_ec_add");
991
992         if (!device)
993                 return_VALUE(-EINVAL);
994
995         ec = kmalloc(sizeof(union acpi_ec), GFP_KERNEL);
996         if (!ec)
997                 return_VALUE(-ENOMEM);
998         memset(ec, 0, sizeof(union acpi_ec));
999
1000         ec->common.handle = device->handle;
1001         ec->common.uid = -1;
1002         spin_lock_init(&ec->polling.lock);
1003         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
1004         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
1005         acpi_driver_data(device) = ec;
1006
1007         /* Use the global lock for all EC transactions? */
1008         acpi_evaluate_integer(ec->common.handle, "_GLK", NULL,
1009                               &ec->common.global_lock);
1010
1011         /* If our UID matches the UID for the ECDT-enumerated EC,
1012            we now have the *real* EC info, so kill the makeshift one. */
1013         acpi_evaluate_integer(ec->common.handle, "_UID", NULL, &uid);
1014         if (ec_ecdt && ec_ecdt->common.uid == uid) {
1015                 acpi_remove_address_space_handler(ACPI_ROOT_OBJECT,
1016                                                   ACPI_ADR_SPACE_EC,
1017                                                   &acpi_ec_space_handler);
1018
1019                 acpi_remove_gpe_handler(NULL, ec_ecdt->common.gpe_bit,
1020                                         &acpi_ec_gpe_handler);
1021
1022                 kfree(ec_ecdt);
1023         }
1024
1025         /* Get GPE bit assignment (EC events). */
1026         /* TODO: Add support for _GPE returning a package */
1027         status =
1028             acpi_evaluate_integer(ec->common.handle, "_GPE", NULL,
1029                                   &ec->common.gpe_bit);
1030         if (ACPI_FAILURE(status)) {
1031                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
1032                                   "Error obtaining GPE bit assignment\n"));
1033                 result = -ENODEV;
1034                 goto end;
1035         }
1036
1037         result = acpi_ec_add_fs(device);
1038         if (result)
1039                 goto end;
1040
1041         printk(KERN_INFO PREFIX "%s [%s] (gpe %d)\n",
1042                acpi_device_name(device), acpi_device_bid(device),
1043                (u32) ec->common.gpe_bit);
1044
1045         if (!first_ec)
1046                 first_ec = device;
1047
1048       end:
1049         if (result)
1050                 kfree(ec);
1051
1052         return_VALUE(result);
1053 }
1054 static int acpi_ec_burst_add(struct acpi_device *device)
1055 {
1056         int result = 0;
1057         acpi_status status = AE_OK;
1058         union acpi_ec *ec = NULL;
1059         unsigned long uid;
1060
1061         ACPI_FUNCTION_TRACE("acpi_ec_add");
1062
1063         if (!device)
1064                 return_VALUE(-EINVAL);
1065
1066         ec = kmalloc(sizeof(union acpi_ec), GFP_KERNEL);
1067         if (!ec)
1068                 return_VALUE(-ENOMEM);
1069         memset(ec, 0, sizeof(union acpi_ec));
1070
1071         ec->common.handle = device->handle;
1072         ec->common.uid = -1;
1073         atomic_set(&ec->burst.pending_gpe, 0);
1074         atomic_set(&ec->burst.leaving_burst, 1);
1075         init_MUTEX(&ec->burst.sem);
1076         init_waitqueue_head(&ec->burst.wait);
1077         strcpy(acpi_device_name(device), ACPI_EC_DEVICE_NAME);
1078         strcpy(acpi_device_class(device), ACPI_EC_CLASS);
1079         acpi_driver_data(device) = ec;
1080
1081         /* Use the global lock for all EC transactions? */
1082         acpi_evaluate_integer(ec->common.handle, "_GLK", NULL,
1083                               &ec->common.global_lock);
1084
1085         /* If our UID matches the UID for the ECDT-enumerated EC,
1086            we now have the *real* EC info, so kill the makeshift one. */
1087         acpi_evaluate_integer(ec->common.handle, "_UID", NULL, &uid);
1088         if (ec_ecdt && ec_ecdt->common.uid == uid) {
1089                 acpi_remove_address_space_handler(ACPI_ROOT_OBJECT,
1090                                                   ACPI_ADR_SPACE_EC,
1091                                                   &acpi_ec_space_handler);
1092
1093                 acpi_remove_gpe_handler(NULL, ec_ecdt->common.gpe_bit,
1094                                         &acpi_ec_gpe_handler);
1095
1096                 kfree(ec_ecdt);
1097         }
1098
1099         /* Get GPE bit assignment (EC events). */
1100         /* TODO: Add support for _GPE returning a package */
1101         status =
1102             acpi_evaluate_integer(ec->common.handle, "_GPE", NULL,
1103                                   &ec->common.gpe_bit);
1104         if (ACPI_FAILURE(status)) {
1105                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
1106                                   "Error obtaining GPE bit assignment\n"));
1107                 result = -ENODEV;
1108                 goto end;
1109         }
1110
1111         result = acpi_ec_add_fs(device);
1112         if (result)
1113                 goto end;
1114
1115         printk("burst-mode-ec-10-Aug\n");
1116         printk(KERN_INFO PREFIX "%s [%s] (gpe %d)\n",
1117                acpi_device_name(device), acpi_device_bid(device),
1118                (u32) ec->common.gpe_bit);
1119
1120         if (!first_ec)
1121                 first_ec = device;
1122
1123       end:
1124         if (result)
1125                 kfree(ec);
1126
1127         return_VALUE(result);
1128 }
1129
1130 static int acpi_ec_remove(struct acpi_device *device, int type)
1131 {
1132         union acpi_ec *ec = NULL;
1133
1134         ACPI_FUNCTION_TRACE("acpi_ec_remove");
1135
1136         if (!device)
1137                 return_VALUE(-EINVAL);
1138
1139         ec = acpi_driver_data(device);
1140
1141         acpi_ec_remove_fs(device);
1142
1143         kfree(ec);
1144
1145         return_VALUE(0);
1146 }
1147
1148 static acpi_status
1149 acpi_ec_io_ports(struct acpi_resource *resource, void *context)
1150 {
1151         union acpi_ec *ec = (union acpi_ec *)context;
1152         struct acpi_generic_address *addr;
1153
1154         if (resource->id != ACPI_RSTYPE_IO) {
1155                 return AE_OK;
1156         }
1157
1158         /*
1159          * The first address region returned is the data port, and
1160          * the second address region returned is the status/command
1161          * port.
1162          */
1163         if (ec->common.data_addr.register_bit_width == 0) {
1164                 addr = &ec->common.data_addr;
1165         } else if (ec->common.command_addr.register_bit_width == 0) {
1166                 addr = &ec->common.command_addr;
1167         } else {
1168                 return AE_CTRL_TERMINATE;
1169         }
1170
1171         addr->address_space_id = ACPI_ADR_SPACE_SYSTEM_IO;
1172         addr->register_bit_width = 8;
1173         addr->register_bit_offset = 0;
1174         addr->address = resource->data.io.min_base_address;
1175
1176         return AE_OK;
1177 }
1178
1179 static int acpi_ec_start(struct acpi_device *device)
1180 {
1181         acpi_status status = AE_OK;
1182         union acpi_ec *ec = NULL;
1183
1184         ACPI_FUNCTION_TRACE("acpi_ec_start");
1185
1186         if (!device)
1187                 return_VALUE(-EINVAL);
1188
1189         ec = acpi_driver_data(device);
1190
1191         if (!ec)
1192                 return_VALUE(-EINVAL);
1193
1194         /*
1195          * Get I/O port addresses. Convert to GAS format.
1196          */
1197         status = acpi_walk_resources(ec->common.handle, METHOD_NAME__CRS,
1198                                      acpi_ec_io_ports, ec);
1199         if (ACPI_FAILURE(status)
1200             || ec->common.command_addr.register_bit_width == 0) {
1201                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
1202                                   "Error getting I/O port addresses"));
1203                 return_VALUE(-ENODEV);
1204         }
1205
1206         ec->common.status_addr = ec->common.command_addr;
1207
1208         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "gpe=0x%02x, ports=0x%2x,0x%2x\n",
1209                           (u32) ec->common.gpe_bit,
1210                           (u32) ec->common.command_addr.address,
1211                           (u32) ec->common.data_addr.address));
1212
1213         /*
1214          * Install GPE handler
1215          */
1216         status = acpi_install_gpe_handler(NULL, ec->common.gpe_bit,
1217                                           ACPI_GPE_EDGE_TRIGGERED,
1218                                           &acpi_ec_gpe_handler, ec);
1219         if (ACPI_FAILURE(status)) {
1220                 return_VALUE(-ENODEV);
1221         }
1222         acpi_set_gpe_type(NULL, ec->common.gpe_bit, ACPI_GPE_TYPE_RUNTIME);
1223         acpi_enable_gpe(NULL, ec->common.gpe_bit, ACPI_NOT_ISR);
1224
1225         status = acpi_install_address_space_handler(ec->common.handle,
1226                                                     ACPI_ADR_SPACE_EC,
1227                                                     &acpi_ec_space_handler,
1228                                                     &acpi_ec_space_setup, ec);
1229         if (ACPI_FAILURE(status)) {
1230                 acpi_remove_gpe_handler(NULL, ec->common.gpe_bit,
1231                                         &acpi_ec_gpe_handler);
1232                 return_VALUE(-ENODEV);
1233         }
1234
1235         return_VALUE(AE_OK);
1236 }
1237
1238 static int acpi_ec_stop(struct acpi_device *device, int type)
1239 {
1240         acpi_status status = AE_OK;
1241         union acpi_ec *ec = NULL;
1242
1243         ACPI_FUNCTION_TRACE("acpi_ec_stop");
1244
1245         if (!device)
1246                 return_VALUE(-EINVAL);
1247
1248         ec = acpi_driver_data(device);
1249
1250         status = acpi_remove_address_space_handler(ec->common.handle,
1251                                                    ACPI_ADR_SPACE_EC,
1252                                                    &acpi_ec_space_handler);
1253         if (ACPI_FAILURE(status))
1254                 return_VALUE(-ENODEV);
1255
1256         status =
1257             acpi_remove_gpe_handler(NULL, ec->common.gpe_bit,
1258                                     &acpi_ec_gpe_handler);
1259         if (ACPI_FAILURE(status))
1260                 return_VALUE(-ENODEV);
1261
1262         return_VALUE(0);
1263 }
1264
1265 static acpi_status __init
1266 acpi_fake_ecdt_callback(acpi_handle handle,
1267                         u32 Level, void *context, void **retval)
1268 {
1269
1270         if (acpi_ec_polling_mode)
1271                 return acpi_fake_ecdt_polling_callback(handle,
1272                                                        Level, context, retval);
1273         else
1274                 return acpi_fake_ecdt_burst_callback(handle,
1275                                                      Level, context, retval);
1276 }
1277
1278 static acpi_status __init
1279 acpi_fake_ecdt_polling_callback(acpi_handle handle,
1280                                 u32 Level, void *context, void **retval)
1281 {
1282         acpi_status status;
1283
1284         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
1285                                      acpi_ec_io_ports, ec_ecdt);
1286         if (ACPI_FAILURE(status))
1287                 return status;
1288         ec_ecdt->common.status_addr = ec_ecdt->common.command_addr;
1289
1290         ec_ecdt->common.uid = -1;
1291         acpi_evaluate_integer(handle, "_UID", NULL, &ec_ecdt->common.uid);
1292
1293         status =
1294             acpi_evaluate_integer(handle, "_GPE", NULL,
1295                                   &ec_ecdt->common.gpe_bit);
1296         if (ACPI_FAILURE(status))
1297                 return status;
1298         spin_lock_init(&ec_ecdt->polling.lock);
1299         ec_ecdt->common.global_lock = TRUE;
1300         ec_ecdt->common.handle = handle;
1301
1302         printk(KERN_INFO PREFIX "GPE=0x%02x, ports=0x%2x, 0x%2x\n",
1303                (u32) ec_ecdt->common.gpe_bit,
1304                (u32) ec_ecdt->common.command_addr.address,
1305                (u32) ec_ecdt->common.data_addr.address);
1306
1307         return AE_CTRL_TERMINATE;
1308 }
1309
1310 static acpi_status __init
1311 acpi_fake_ecdt_burst_callback(acpi_handle handle,
1312                               u32 Level, void *context, void **retval)
1313 {
1314         acpi_status status;
1315
1316         init_MUTEX(&ec_ecdt->burst.sem);
1317         init_waitqueue_head(&ec_ecdt->burst.wait);
1318         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
1319                                      acpi_ec_io_ports, ec_ecdt);
1320         if (ACPI_FAILURE(status))
1321                 return status;
1322         ec_ecdt->common.status_addr = ec_ecdt->common.command_addr;
1323
1324         ec_ecdt->common.uid = -1;
1325         acpi_evaluate_integer(handle, "_UID", NULL, &ec_ecdt->common.uid);
1326
1327         status =
1328             acpi_evaluate_integer(handle, "_GPE", NULL,
1329                                   &ec_ecdt->common.gpe_bit);
1330         if (ACPI_FAILURE(status))
1331                 return status;
1332         ec_ecdt->common.global_lock = TRUE;
1333         ec_ecdt->common.handle = handle;
1334
1335         printk(KERN_INFO PREFIX "GPE=0x%02x, ports=0x%2x, 0x%2x\n",
1336                (u32) ec_ecdt->common.gpe_bit,
1337                (u32) ec_ecdt->common.command_addr.address,
1338                (u32) ec_ecdt->common.data_addr.address);
1339
1340         return AE_CTRL_TERMINATE;
1341 }
1342
1343 /*
1344  * Some BIOS (such as some from Gateway laptops) access EC region very early
1345  * such as in BAT0._INI or EC._INI before an EC device is found and
1346  * do not provide an ECDT. According to ACPI spec, ECDT isn't mandatorily
1347  * required, but if EC regison is accessed early, it is required.
1348  * The routine tries to workaround the BIOS bug by pre-scan EC device
1349  * It assumes that _CRS, _HID, _GPE, _UID methods of EC don't touch any
1350  * op region (since _REG isn't invoked yet). The assumption is true for
1351  * all systems found.
1352  */
1353 static int __init acpi_ec_fake_ecdt(void)
1354 {
1355         acpi_status status;
1356         int ret = 0;
1357
1358         printk(KERN_INFO PREFIX "Try to make an fake ECDT\n");
1359
1360         ec_ecdt = kmalloc(sizeof(union acpi_ec), GFP_KERNEL);
1361         if (!ec_ecdt) {
1362                 ret = -ENOMEM;
1363                 goto error;
1364         }
1365         memset(ec_ecdt, 0, sizeof(union acpi_ec));
1366
1367         status = acpi_get_devices(ACPI_EC_HID,
1368                                   acpi_fake_ecdt_callback, NULL, NULL);
1369         if (ACPI_FAILURE(status)) {
1370                 kfree(ec_ecdt);
1371                 ec_ecdt = NULL;
1372                 ret = -ENODEV;
1373                 goto error;
1374         }
1375         return 0;
1376       error:
1377         printk(KERN_ERR PREFIX "Can't make an fake ECDT\n");
1378         return ret;
1379 }
1380
1381 static int __init acpi_ec_get_real_ecdt(void)
1382 {
1383         if (acpi_ec_polling_mode)
1384                 return acpi_ec_polling_get_real_ecdt();
1385         else
1386                 return acpi_ec_burst_get_real_ecdt();
1387 }
1388
1389 static int __init acpi_ec_polling_get_real_ecdt(void)
1390 {
1391         acpi_status status;
1392         struct acpi_table_ecdt *ecdt_ptr;
1393
1394         status = acpi_get_firmware_table("ECDT", 1, ACPI_LOGICAL_ADDRESSING,
1395                                          (struct acpi_table_header **)
1396                                          &ecdt_ptr);
1397         if (ACPI_FAILURE(status))
1398                 return -ENODEV;
1399
1400         printk(KERN_INFO PREFIX "Found ECDT\n");
1401
1402         /*
1403          * Generate a temporary ec context to use until the namespace is scanned
1404          */
1405         ec_ecdt = kmalloc(sizeof(union acpi_ec), GFP_KERNEL);
1406         if (!ec_ecdt)
1407                 return -ENOMEM;
1408         memset(ec_ecdt, 0, sizeof(union acpi_ec));
1409
1410         ec_ecdt->common.command_addr = ecdt_ptr->ec_control;
1411         ec_ecdt->common.status_addr = ecdt_ptr->ec_control;
1412         ec_ecdt->common.data_addr = ecdt_ptr->ec_data;
1413         ec_ecdt->common.gpe_bit = ecdt_ptr->gpe_bit;
1414         spin_lock_init(&ec_ecdt->polling.lock);
1415         /* use the GL just to be safe */
1416         ec_ecdt->common.global_lock = TRUE;
1417         ec_ecdt->common.uid = ecdt_ptr->uid;
1418
1419         status =
1420             acpi_get_handle(NULL, ecdt_ptr->ec_id, &ec_ecdt->common.handle);
1421         if (ACPI_FAILURE(status)) {
1422                 goto error;
1423         }
1424
1425         return 0;
1426       error:
1427         printk(KERN_ERR PREFIX "Could not use ECDT\n");
1428         kfree(ec_ecdt);
1429         ec_ecdt = NULL;
1430
1431         return -ENODEV;
1432 }
1433
1434 static int __init acpi_ec_burst_get_real_ecdt(void)
1435 {
1436         acpi_status status;
1437         struct acpi_table_ecdt *ecdt_ptr;
1438
1439         status = acpi_get_firmware_table("ECDT", 1, ACPI_LOGICAL_ADDRESSING,
1440                                          (struct acpi_table_header **)
1441                                          &ecdt_ptr);
1442         if (ACPI_FAILURE(status))
1443                 return -ENODEV;
1444
1445         printk(KERN_INFO PREFIX "Found ECDT\n");
1446
1447         /*
1448          * Generate a temporary ec context to use until the namespace is scanned
1449          */
1450         ec_ecdt = kmalloc(sizeof(union acpi_ec), GFP_KERNEL);
1451         if (!ec_ecdt)
1452                 return -ENOMEM;
1453         memset(ec_ecdt, 0, sizeof(union acpi_ec));
1454
1455         init_MUTEX(&ec_ecdt->burst.sem);
1456         init_waitqueue_head(&ec_ecdt->burst.wait);
1457         ec_ecdt->common.command_addr = ecdt_ptr->ec_control;
1458         ec_ecdt->common.status_addr = ecdt_ptr->ec_control;
1459         ec_ecdt->common.data_addr = ecdt_ptr->ec_data;
1460         ec_ecdt->common.gpe_bit = ecdt_ptr->gpe_bit;
1461         /* use the GL just to be safe */
1462         ec_ecdt->common.global_lock = TRUE;
1463         ec_ecdt->common.uid = ecdt_ptr->uid;
1464
1465         status =
1466             acpi_get_handle(NULL, ecdt_ptr->ec_id, &ec_ecdt->common.handle);
1467         if (ACPI_FAILURE(status)) {
1468                 goto error;
1469         }
1470
1471         return 0;
1472       error:
1473         printk(KERN_ERR PREFIX "Could not use ECDT\n");
1474         kfree(ec_ecdt);
1475         ec_ecdt = NULL;
1476
1477         return -ENODEV;
1478 }
1479
1480 static int __initdata acpi_fake_ecdt_enabled;
1481 int __init acpi_ec_ecdt_probe(void)
1482 {
1483         acpi_status status;
1484         int ret;
1485
1486         ret = acpi_ec_get_real_ecdt();
1487         /* Try to make a fake ECDT */
1488         if (ret && acpi_fake_ecdt_enabled) {
1489                 ret = acpi_ec_fake_ecdt();
1490         }
1491
1492         if (ret)
1493                 return 0;
1494
1495         /*
1496          * Install GPE handler
1497          */
1498         status = acpi_install_gpe_handler(NULL, ec_ecdt->common.gpe_bit,
1499                                           ACPI_GPE_EDGE_TRIGGERED,
1500                                           &acpi_ec_gpe_handler, ec_ecdt);
1501         if (ACPI_FAILURE(status)) {
1502                 goto error;
1503         }
1504         acpi_set_gpe_type(NULL, ec_ecdt->common.gpe_bit, ACPI_GPE_TYPE_RUNTIME);
1505         acpi_enable_gpe(NULL, ec_ecdt->common.gpe_bit, ACPI_NOT_ISR);
1506
1507         status = acpi_install_address_space_handler(ACPI_ROOT_OBJECT,
1508                                                     ACPI_ADR_SPACE_EC,
1509                                                     &acpi_ec_space_handler,
1510                                                     &acpi_ec_space_setup,
1511                                                     ec_ecdt);
1512         if (ACPI_FAILURE(status)) {
1513                 acpi_remove_gpe_handler(NULL, ec_ecdt->common.gpe_bit,
1514                                         &acpi_ec_gpe_handler);
1515                 goto error;
1516         }
1517
1518         return 0;
1519
1520       error:
1521         printk(KERN_ERR PREFIX "Could not use ECDT\n");
1522         kfree(ec_ecdt);
1523         ec_ecdt = NULL;
1524
1525         return -ENODEV;
1526 }
1527
1528 static int __init acpi_ec_init(void)
1529 {
1530         int result = 0;
1531
1532         ACPI_FUNCTION_TRACE("acpi_ec_init");
1533
1534         if (acpi_disabled)
1535                 return_VALUE(0);
1536
1537         acpi_ec_dir = proc_mkdir(ACPI_EC_CLASS, acpi_root_dir);
1538         if (!acpi_ec_dir)
1539                 return_VALUE(-ENODEV);
1540
1541         /* Now register the driver for the EC */
1542         result = acpi_bus_register_driver(&acpi_ec_driver);
1543         if (result < 0) {
1544                 remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1545                 return_VALUE(-ENODEV);
1546         }
1547
1548         return_VALUE(result);
1549 }
1550
1551 subsys_initcall(acpi_ec_init);
1552
1553 /* EC driver currently not unloadable */
1554 #if 0
1555 static void __exit acpi_ec_exit(void)
1556 {
1557         ACPI_FUNCTION_TRACE("acpi_ec_exit");
1558
1559         acpi_bus_unregister_driver(&acpi_ec_driver);
1560
1561         remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
1562
1563         return_VOID;
1564 }
1565 #endif                          /* 0 */
1566
1567 static int __init acpi_fake_ecdt_setup(char *str)
1568 {
1569         acpi_fake_ecdt_enabled = 1;
1570         return 0;
1571 }
1572
1573 __setup("acpi_fake_ecdt", acpi_fake_ecdt_setup);
1574 static int __init acpi_ec_set_polling_mode(char *str)
1575 {
1576         int burst;
1577
1578         if (!get_option(&str, &burst))
1579                 return 0;
1580
1581         if (burst) {
1582                 acpi_ec_polling_mode = EC_BURST;
1583                 acpi_ec_driver.ops.add = acpi_ec_burst_add;
1584         } else {
1585                 acpi_ec_polling_mode = EC_POLLING;
1586                 acpi_ec_driver.ops.add = acpi_ec_polling_add;
1587         }
1588         printk(KERN_INFO PREFIX "EC %s mode.\n", burst ? "burst" : "polling");
1589         return 0;
1590 }
1591
1592 __setup("ec_burst=", acpi_ec_set_polling_mode);