xref: /linux/drivers/acpi/ec.c (revision 5e8d780d745c1619aba81fe7166c5a4b5cad2b84)
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);
1600