xref: /freebsd/sys/dev/acpica/acpi_ec.c (revision 5861f9665471e98e544f6fa3ce73c4912229ff82)
1 /*-
2  * Copyright (c) 2003-2007 Nate Lawson
3  * Copyright (c) 2000 Michael Smith
4  * Copyright (c) 2000 BSDi
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
31 
32 #include "opt_acpi.h"
33 #include <sys/param.h>
34 #include <sys/kernel.h>
35 #include <sys/bus.h>
36 #include <sys/lock.h>
37 #include <sys/malloc.h>
38 #include <sys/module.h>
39 #include <sys/sx.h>
40 
41 #include <machine/bus.h>
42 #include <machine/resource.h>
43 #include <sys/rman.h>
44 
45 #include <contrib/dev/acpica/include/acpi.h>
46 #include <contrib/dev/acpica/include/accommon.h>
47 
48 #include <dev/acpica/acpivar.h>
49 
50 /* Hooks for the ACPI CA debugging infrastructure */
51 #define _COMPONENT	ACPI_EC
52 ACPI_MODULE_NAME("EC")
53 
54 /*
55  * EC_COMMAND:
56  * -----------
57  */
58 typedef UINT8				EC_COMMAND;
59 
60 #define EC_COMMAND_UNKNOWN		((EC_COMMAND) 0x00)
61 #define EC_COMMAND_READ			((EC_COMMAND) 0x80)
62 #define EC_COMMAND_WRITE		((EC_COMMAND) 0x81)
63 #define EC_COMMAND_BURST_ENABLE		((EC_COMMAND) 0x82)
64 #define EC_COMMAND_BURST_DISABLE	((EC_COMMAND) 0x83)
65 #define EC_COMMAND_QUERY		((EC_COMMAND) 0x84)
66 
67 /*
68  * EC_STATUS:
69  * ----------
70  * The encoding of the EC status register is illustrated below.
71  * Note that a set bit (1) indicates the property is TRUE
72  * (e.g. if bit 0 is set then the output buffer is full).
73  * +-+-+-+-+-+-+-+-+
74  * |7|6|5|4|3|2|1|0|
75  * +-+-+-+-+-+-+-+-+
76  *  | | | | | | | |
77  *  | | | | | | | +- Output Buffer Full?
78  *  | | | | | | +--- Input Buffer Full?
79  *  | | | | | +----- <reserved>
80  *  | | | | +------- Data Register is Command Byte?
81  *  | | | +--------- Burst Mode Enabled?
82  *  | | +----------- SCI Event?
83  *  | +------------- SMI Event?
84  *  +--------------- <reserved>
85  *
86  */
87 typedef UINT8				EC_STATUS;
88 
89 #define EC_FLAG_OUTPUT_BUFFER		((EC_STATUS) 0x01)
90 #define EC_FLAG_INPUT_BUFFER		((EC_STATUS) 0x02)
91 #define EC_FLAG_DATA_IS_CMD		((EC_STATUS) 0x08)
92 #define EC_FLAG_BURST_MODE		((EC_STATUS) 0x10)
93 
94 /*
95  * EC_EVENT:
96  * ---------
97  */
98 typedef UINT8				EC_EVENT;
99 
100 #define EC_EVENT_UNKNOWN		((EC_EVENT) 0x00)
101 #define EC_EVENT_OUTPUT_BUFFER_FULL	((EC_EVENT) 0x01)
102 #define EC_EVENT_INPUT_BUFFER_EMPTY	((EC_EVENT) 0x02)
103 #define EC_EVENT_SCI			((EC_EVENT) 0x20)
104 #define EC_EVENT_SMI			((EC_EVENT) 0x40)
105 
106 /* Data byte returned after burst enable indicating it was successful. */
107 #define EC_BURST_ACK			0x90
108 
109 /*
110  * Register access primitives
111  */
112 #define EC_GET_DATA(sc)							\
113 	bus_space_read_1((sc)->ec_data_tag, (sc)->ec_data_handle, 0)
114 
115 #define EC_SET_DATA(sc, v)						\
116 	bus_space_write_1((sc)->ec_data_tag, (sc)->ec_data_handle, 0, (v))
117 
118 #define EC_GET_CSR(sc)							\
119 	bus_space_read_1((sc)->ec_csr_tag, (sc)->ec_csr_handle, 0)
120 
121 #define EC_SET_CSR(sc, v)						\
122 	bus_space_write_1((sc)->ec_csr_tag, (sc)->ec_csr_handle, 0, (v))
123 
124 /* Additional params to pass from the probe routine */
125 struct acpi_ec_params {
126     int		glk;
127     int		gpe_bit;
128     ACPI_HANDLE	gpe_handle;
129     int		uid;
130 };
131 
132 /* Indicate that this device has already been probed via ECDT. */
133 #define DEV_ECDT(x)	(acpi_get_magic(x) == (uintptr_t)&acpi_ec_devclass)
134 
135 /*
136  * Driver softc.
137  */
138 struct acpi_ec_softc {
139     device_t		ec_dev;
140     ACPI_HANDLE		ec_handle;
141     int			ec_uid;
142     ACPI_HANDLE		ec_gpehandle;
143     UINT8		ec_gpebit;
144 
145     int			ec_data_rid;
146     struct resource	*ec_data_res;
147     bus_space_tag_t	ec_data_tag;
148     bus_space_handle_t	ec_data_handle;
149 
150     int			ec_csr_rid;
151     struct resource	*ec_csr_res;
152     bus_space_tag_t	ec_csr_tag;
153     bus_space_handle_t	ec_csr_handle;
154 
155     int			ec_glk;
156     int			ec_glkhandle;
157     int			ec_burstactive;
158     int			ec_sci_pend;
159     u_int		ec_gencount;
160     int			ec_suspending;
161 };
162 
163 /*
164  * XXX njl
165  * I couldn't find it in the spec but other implementations also use a
166  * value of 1 ms for the time to acquire global lock.
167  */
168 #define EC_LOCK_TIMEOUT	1000
169 
170 /* Default delay in microseconds between each run of the status polling loop. */
171 #define EC_POLL_DELAY	5
172 
173 /* Total time in ms spent waiting for a response from EC. */
174 #define EC_TIMEOUT	750
175 
176 #define EVENT_READY(event, status)			\
177 	(((event) == EC_EVENT_OUTPUT_BUFFER_FULL &&	\
178 	 ((status) & EC_FLAG_OUTPUT_BUFFER) != 0) ||	\
179 	 ((event) == EC_EVENT_INPUT_BUFFER_EMPTY && 	\
180 	 ((status) & EC_FLAG_INPUT_BUFFER) == 0))
181 
182 ACPI_SERIAL_DECL(ec, "ACPI embedded controller");
183 
184 SYSCTL_DECL(_debug_acpi);
185 SYSCTL_NODE(_debug_acpi, OID_AUTO, ec, CTLFLAG_RD, NULL, "EC debugging");
186 
187 static int	ec_burst_mode;
188 TUNABLE_INT("debug.acpi.ec.burst", &ec_burst_mode);
189 SYSCTL_INT(_debug_acpi_ec, OID_AUTO, burst, CTLFLAG_RW, &ec_burst_mode, 0,
190     "Enable use of burst mode (faster for nearly all systems)");
191 static int	ec_polled_mode;
192 TUNABLE_INT("debug.acpi.ec.polled", &ec_polled_mode);
193 SYSCTL_INT(_debug_acpi_ec, OID_AUTO, polled, CTLFLAG_RW, &ec_polled_mode, 0,
194     "Force use of polled mode (only if interrupt mode doesn't work)");
195 static int	ec_timeout = EC_TIMEOUT;
196 TUNABLE_INT("debug.acpi.ec.timeout", &ec_timeout);
197 SYSCTL_INT(_debug_acpi_ec, OID_AUTO, timeout, CTLFLAG_RW, &ec_timeout,
198     EC_TIMEOUT, "Total time spent waiting for a response (poll+sleep)");
199 
200 static ACPI_STATUS
201 EcLock(struct acpi_ec_softc *sc)
202 {
203     ACPI_STATUS	status;
204 
205     /* If _GLK is non-zero, acquire the global lock. */
206     status = AE_OK;
207     if (sc->ec_glk) {
208 	status = AcpiAcquireGlobalLock(EC_LOCK_TIMEOUT, &sc->ec_glkhandle);
209 	if (ACPI_FAILURE(status))
210 	    return (status);
211     }
212     ACPI_SERIAL_BEGIN(ec);
213     return (status);
214 }
215 
216 static void
217 EcUnlock(struct acpi_ec_softc *sc)
218 {
219     ACPI_SERIAL_END(ec);
220     if (sc->ec_glk)
221 	AcpiReleaseGlobalLock(sc->ec_glkhandle);
222 }
223 
224 static uint32_t		EcGpeHandler(void *Context);
225 static ACPI_STATUS	EcSpaceSetup(ACPI_HANDLE Region, UINT32 Function,
226 				void *Context, void **return_Context);
227 static ACPI_STATUS	EcSpaceHandler(UINT32 Function,
228 				ACPI_PHYSICAL_ADDRESS Address,
229 				UINT32 width, ACPI_INTEGER *Value,
230 				void *Context, void *RegionContext);
231 static ACPI_STATUS	EcWaitEvent(struct acpi_ec_softc *sc, EC_EVENT Event,
232 				u_int gen_count);
233 static ACPI_STATUS	EcCommand(struct acpi_ec_softc *sc, EC_COMMAND cmd);
234 static ACPI_STATUS	EcRead(struct acpi_ec_softc *sc, UINT8 Address,
235 				UINT8 *Data);
236 static ACPI_STATUS	EcWrite(struct acpi_ec_softc *sc, UINT8 Address,
237 				UINT8 *Data);
238 static int		acpi_ec_probe(device_t dev);
239 static int		acpi_ec_attach(device_t dev);
240 static int		acpi_ec_suspend(device_t dev);
241 static int		acpi_ec_resume(device_t dev);
242 static int		acpi_ec_shutdown(device_t dev);
243 static int		acpi_ec_read_method(device_t dev, u_int addr,
244 				ACPI_INTEGER *val, int width);
245 static int		acpi_ec_write_method(device_t dev, u_int addr,
246 				ACPI_INTEGER val, int width);
247 
248 static device_method_t acpi_ec_methods[] = {
249     /* Device interface */
250     DEVMETHOD(device_probe,	acpi_ec_probe),
251     DEVMETHOD(device_attach,	acpi_ec_attach),
252     DEVMETHOD(device_suspend,	acpi_ec_suspend),
253     DEVMETHOD(device_resume,	acpi_ec_resume),
254     DEVMETHOD(device_shutdown,	acpi_ec_shutdown),
255 
256     /* Embedded controller interface */
257     DEVMETHOD(acpi_ec_read,	acpi_ec_read_method),
258     DEVMETHOD(acpi_ec_write,	acpi_ec_write_method),
259 
260     {0, 0}
261 };
262 
263 static driver_t acpi_ec_driver = {
264     "acpi_ec",
265     acpi_ec_methods,
266     sizeof(struct acpi_ec_softc),
267 };
268 
269 static devclass_t acpi_ec_devclass;
270 DRIVER_MODULE(acpi_ec, acpi, acpi_ec_driver, acpi_ec_devclass, 0, 0);
271 MODULE_DEPEND(acpi_ec, acpi, 1, 1, 1);
272 
273 /*
274  * Look for an ECDT and if we find one, set up default GPE and
275  * space handlers to catch attempts to access EC space before
276  * we have a real driver instance in place.
277  *
278  * TODO: Some old Gateway laptops need us to fake up an ECDT or
279  * otherwise attach early so that _REG methods can run.
280  */
281 void
282 acpi_ec_ecdt_probe(device_t parent)
283 {
284     ACPI_TABLE_ECDT *ecdt;
285     ACPI_STATUS	     status;
286     device_t	     child;
287     ACPI_HANDLE	     h;
288     struct acpi_ec_params *params;
289 
290     ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
291 
292     /* Find and validate the ECDT. */
293     status = AcpiGetTable(ACPI_SIG_ECDT, 1, (ACPI_TABLE_HEADER **)&ecdt);
294     if (ACPI_FAILURE(status) ||
295 	ecdt->Control.BitWidth != 8 ||
296 	ecdt->Data.BitWidth != 8) {
297 	return;
298     }
299 
300     /* Create the child device with the given unit number. */
301     child = BUS_ADD_CHILD(parent, 0, "acpi_ec", ecdt->Uid);
302     if (child == NULL) {
303 	printf("%s: can't add child\n", __func__);
304 	return;
305     }
306 
307     /* Find and save the ACPI handle for this device. */
308     status = AcpiGetHandle(NULL, ecdt->Id, &h);
309     if (ACPI_FAILURE(status)) {
310 	device_delete_child(parent, child);
311 	printf("%s: can't get handle\n", __func__);
312 	return;
313     }
314     acpi_set_handle(child, h);
315 
316     /* Set the data and CSR register addresses. */
317     bus_set_resource(child, SYS_RES_IOPORT, 0, ecdt->Data.Address,
318 	/*count*/1);
319     bus_set_resource(child, SYS_RES_IOPORT, 1, ecdt->Control.Address,
320 	/*count*/1);
321 
322     /*
323      * Store values for the probe/attach routines to use.  Store the
324      * ECDT GPE bit and set the global lock flag according to _GLK.
325      * Note that it is not perfectly correct to be evaluating a method
326      * before initializing devices, but in practice this function
327      * should be safe to call at this point.
328      */
329     params = malloc(sizeof(struct acpi_ec_params), M_TEMP, M_WAITOK | M_ZERO);
330     params->gpe_handle = NULL;
331     params->gpe_bit = ecdt->Gpe;
332     params->uid = ecdt->Uid;
333     acpi_GetInteger(h, "_GLK", &params->glk);
334     acpi_set_private(child, params);
335     acpi_set_magic(child, (uintptr_t)&acpi_ec_devclass);
336 
337     /* Finish the attach process. */
338     if (device_probe_and_attach(child) != 0)
339 	device_delete_child(parent, child);
340 }
341 
342 static int
343 acpi_ec_probe(device_t dev)
344 {
345     ACPI_BUFFER buf;
346     ACPI_HANDLE h;
347     ACPI_OBJECT *obj;
348     ACPI_STATUS status;
349     device_t	peer;
350     char	desc[64];
351     int		ret;
352     struct acpi_ec_params *params;
353     static char *ec_ids[] = { "PNP0C09", NULL };
354 
355     /* Check that this is a device and that EC is not disabled. */
356     if (acpi_get_type(dev) != ACPI_TYPE_DEVICE || acpi_disabled("ec"))
357 	return (ENXIO);
358 
359     /*
360      * If probed via ECDT, set description and continue.  Otherwise,
361      * we can access the namespace and make sure this is not a
362      * duplicate probe.
363      */
364     ret = ENXIO;
365     params = NULL;
366     buf.Pointer = NULL;
367     buf.Length = ACPI_ALLOCATE_BUFFER;
368     if (DEV_ECDT(dev)) {
369 	params = acpi_get_private(dev);
370 	ret = 0;
371     } else if (!acpi_disabled("ec") &&
372 	ACPI_ID_PROBE(device_get_parent(dev), dev, ec_ids)) {
373 	params = malloc(sizeof(struct acpi_ec_params), M_TEMP,
374 			M_WAITOK | M_ZERO);
375 	h = acpi_get_handle(dev);
376 
377 	/*
378 	 * Read the unit ID to check for duplicate attach and the
379 	 * global lock value to see if we should acquire it when
380 	 * accessing the EC.
381 	 */
382 	status = acpi_GetInteger(h, "_UID", &params->uid);
383 	if (ACPI_FAILURE(status))
384 	    params->uid = 0;
385 	status = acpi_GetInteger(h, "_GLK", &params->glk);
386 	if (ACPI_FAILURE(status))
387 	    params->glk = 0;
388 
389 	/*
390 	 * Evaluate the _GPE method to find the GPE bit used by the EC to
391 	 * signal status (SCI).  If it's a package, it contains a reference
392 	 * and GPE bit, similar to _PRW.
393 	 */
394 	status = AcpiEvaluateObject(h, "_GPE", NULL, &buf);
395 	if (ACPI_FAILURE(status)) {
396 	    device_printf(dev, "can't evaluate _GPE - %s\n",
397 			  AcpiFormatException(status));
398 	    goto out;
399 	}
400 	obj = (ACPI_OBJECT *)buf.Pointer;
401 	if (obj == NULL)
402 	    goto out;
403 
404 	switch (obj->Type) {
405 	case ACPI_TYPE_INTEGER:
406 	    params->gpe_handle = NULL;
407 	    params->gpe_bit = obj->Integer.Value;
408 	    break;
409 	case ACPI_TYPE_PACKAGE:
410 	    if (!ACPI_PKG_VALID(obj, 2))
411 		goto out;
412 	    params->gpe_handle =
413 		acpi_GetReference(NULL, &obj->Package.Elements[0]);
414 	    if (params->gpe_handle == NULL ||
415 		acpi_PkgInt32(obj, 1, &params->gpe_bit) != 0)
416 		goto out;
417 	    break;
418 	default:
419 	    device_printf(dev, "_GPE has invalid type %d\n", obj->Type);
420 	    goto out;
421 	}
422 
423 	/* Store the values we got from the namespace for attach. */
424 	acpi_set_private(dev, params);
425 
426 	/*
427 	 * Check for a duplicate probe.  This can happen when a probe
428 	 * via ECDT succeeded already.  If this is a duplicate, disable
429 	 * this device.
430 	 */
431 	peer = devclass_get_device(acpi_ec_devclass, params->uid);
432 	if (peer == NULL || !device_is_alive(peer))
433 	    ret = 0;
434 	else
435 	    device_disable(dev);
436     }
437 
438 out:
439     if (ret == 0) {
440 	snprintf(desc, sizeof(desc), "Embedded Controller: GPE %#x%s%s",
441 		 params->gpe_bit, (params->glk) ? ", GLK" : "",
442 		 DEV_ECDT(dev) ? ", ECDT" : "");
443 	device_set_desc_copy(dev, desc);
444     }
445 
446     if (ret > 0 && params)
447 	free(params, M_TEMP);
448     if (buf.Pointer)
449 	AcpiOsFree(buf.Pointer);
450     return (ret);
451 }
452 
453 static int
454 acpi_ec_attach(device_t dev)
455 {
456     struct acpi_ec_softc	*sc;
457     struct acpi_ec_params	*params;
458     ACPI_STATUS			Status;
459 
460     ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
461 
462     /* Fetch/initialize softc (assumes softc is pre-zeroed). */
463     sc = device_get_softc(dev);
464     params = acpi_get_private(dev);
465     sc->ec_dev = dev;
466     sc->ec_handle = acpi_get_handle(dev);
467 
468     /* Retrieve previously probed values via device ivars. */
469     sc->ec_glk = params->glk;
470     sc->ec_gpebit = params->gpe_bit;
471     sc->ec_gpehandle = params->gpe_handle;
472     sc->ec_uid = params->uid;
473     sc->ec_suspending = FALSE;
474     free(params, M_TEMP);
475 
476     /* Attach bus resources for data and command/status ports. */
477     sc->ec_data_rid = 0;
478     sc->ec_data_res = bus_alloc_resource_any(sc->ec_dev, SYS_RES_IOPORT,
479 			&sc->ec_data_rid, RF_ACTIVE);
480     if (sc->ec_data_res == NULL) {
481 	device_printf(dev, "can't allocate data port\n");
482 	goto error;
483     }
484     sc->ec_data_tag = rman_get_bustag(sc->ec_data_res);
485     sc->ec_data_handle = rman_get_bushandle(sc->ec_data_res);
486 
487     sc->ec_csr_rid = 1;
488     sc->ec_csr_res = bus_alloc_resource_any(sc->ec_dev, SYS_RES_IOPORT,
489 			&sc->ec_csr_rid, RF_ACTIVE);
490     if (sc->ec_csr_res == NULL) {
491 	device_printf(dev, "can't allocate command/status port\n");
492 	goto error;
493     }
494     sc->ec_csr_tag = rman_get_bustag(sc->ec_csr_res);
495     sc->ec_csr_handle = rman_get_bushandle(sc->ec_csr_res);
496 
497     /*
498      * Install a handler for this EC's GPE bit.  We want edge-triggered
499      * behavior.
500      */
501     ACPI_DEBUG_PRINT((ACPI_DB_RESOURCES, "attaching GPE handler\n"));
502     Status = AcpiInstallGpeHandler(sc->ec_gpehandle, sc->ec_gpebit,
503 		ACPI_GPE_EDGE_TRIGGERED, &EcGpeHandler, sc);
504     if (ACPI_FAILURE(Status)) {
505 	device_printf(dev, "can't install GPE handler for %s - %s\n",
506 		      acpi_name(sc->ec_handle), AcpiFormatException(Status));
507 	goto error;
508     }
509 
510     /*
511      * Install address space handler
512      */
513     ACPI_DEBUG_PRINT((ACPI_DB_RESOURCES, "attaching address space handler\n"));
514     Status = AcpiInstallAddressSpaceHandler(sc->ec_handle, ACPI_ADR_SPACE_EC,
515 		&EcSpaceHandler, &EcSpaceSetup, sc);
516     if (ACPI_FAILURE(Status)) {
517 	device_printf(dev, "can't install address space handler for %s - %s\n",
518 		      acpi_name(sc->ec_handle), AcpiFormatException(Status));
519 	goto error;
520     }
521 
522     /* Enable runtime GPEs for the handler. */
523     Status = AcpiSetGpeType(sc->ec_gpehandle, sc->ec_gpebit,
524 			    ACPI_GPE_TYPE_RUNTIME);
525     if (ACPI_FAILURE(Status)) {
526 	device_printf(dev, "AcpiSetGpeType failed: %s\n",
527 		      AcpiFormatException(Status));
528 	goto error;
529     }
530     Status = AcpiEnableGpe(sc->ec_gpehandle, sc->ec_gpebit, ACPI_NOT_ISR);
531     if (ACPI_FAILURE(Status)) {
532 	device_printf(dev, "AcpiEnableGpe failed: %s\n",
533 		      AcpiFormatException(Status));
534 	goto error;
535     }
536 
537     ACPI_DEBUG_PRINT((ACPI_DB_RESOURCES, "acpi_ec_attach complete\n"));
538     return (0);
539 
540 error:
541     AcpiRemoveGpeHandler(sc->ec_gpehandle, sc->ec_gpebit, &EcGpeHandler);
542     AcpiRemoveAddressSpaceHandler(sc->ec_handle, ACPI_ADR_SPACE_EC,
543 	EcSpaceHandler);
544     if (sc->ec_csr_res)
545 	bus_release_resource(sc->ec_dev, SYS_RES_IOPORT, sc->ec_csr_rid,
546 			     sc->ec_csr_res);
547     if (sc->ec_data_res)
548 	bus_release_resource(sc->ec_dev, SYS_RES_IOPORT, sc->ec_data_rid,
549 			     sc->ec_data_res);
550     return (ENXIO);
551 }
552 
553 static int
554 acpi_ec_suspend(device_t dev)
555 {
556     struct acpi_ec_softc	*sc;
557 
558     sc = device_get_softc(dev);
559     sc->ec_suspending = TRUE;
560     return (0);
561 }
562 
563 static int
564 acpi_ec_resume(device_t dev)
565 {
566     struct acpi_ec_softc	*sc;
567 
568     sc = device_get_softc(dev);
569     sc->ec_suspending = FALSE;
570     return (0);
571 }
572 
573 static int
574 acpi_ec_shutdown(device_t dev)
575 {
576     struct acpi_ec_softc	*sc;
577 
578     /* Disable the GPE so we don't get EC events during shutdown. */
579     sc = device_get_softc(dev);
580     AcpiDisableGpe(sc->ec_gpehandle, sc->ec_gpebit, ACPI_NOT_ISR);
581     return (0);
582 }
583 
584 /* Methods to allow other devices (e.g., smbat) to read/write EC space. */
585 static int
586 acpi_ec_read_method(device_t dev, u_int addr, ACPI_INTEGER *val, int width)
587 {
588     struct acpi_ec_softc *sc;
589     ACPI_STATUS status;
590 
591     sc = device_get_softc(dev);
592     status = EcSpaceHandler(ACPI_READ, addr, width * 8, val, sc, NULL);
593     if (ACPI_FAILURE(status))
594 	return (ENXIO);
595     return (0);
596 }
597 
598 static int
599 acpi_ec_write_method(device_t dev, u_int addr, ACPI_INTEGER val, int width)
600 {
601     struct acpi_ec_softc *sc;
602     ACPI_STATUS status;
603 
604     sc = device_get_softc(dev);
605     status = EcSpaceHandler(ACPI_WRITE, addr, width * 8, &val, sc, NULL);
606     if (ACPI_FAILURE(status))
607 	return (ENXIO);
608     return (0);
609 }
610 
611 static void
612 EcGpeQueryHandler(void *Context)
613 {
614     struct acpi_ec_softc	*sc = (struct acpi_ec_softc *)Context;
615     UINT8			Data;
616     ACPI_STATUS			Status;
617     char			qxx[5];
618 
619     ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
620     KASSERT(Context != NULL, ("EcGpeQueryHandler called with NULL"));
621 
622     /* Serialize user access with EcSpaceHandler(). */
623     Status = EcLock(sc);
624     if (ACPI_FAILURE(Status)) {
625 	device_printf(sc->ec_dev, "GpeQuery lock error: %s\n",
626 	    AcpiFormatException(Status));
627 	return;
628     }
629 
630     /*
631      * Send a query command to the EC to find out which _Qxx call it
632      * wants to make.  This command clears the SCI bit and also the
633      * interrupt source since we are edge-triggered.  To prevent the GPE
634      * that may arise from running the query from causing another query
635      * to be queued, we clear the pending flag only after running it.
636      */
637     Status = EcCommand(sc, EC_COMMAND_QUERY);
638     sc->ec_sci_pend = FALSE;
639     if (ACPI_FAILURE(Status)) {
640 	EcUnlock(sc);
641 	device_printf(sc->ec_dev, "GPE query failed: %s\n",
642 	    AcpiFormatException(Status));
643 	return;
644     }
645     Data = EC_GET_DATA(sc);
646 
647     /*
648      * We have to unlock before running the _Qxx method below since that
649      * method may attempt to read/write from EC address space, causing
650      * recursive acquisition of the lock.
651      */
652     EcUnlock(sc);
653 
654     /* Ignore the value for "no outstanding event". (13.3.5) */
655     CTR2(KTR_ACPI, "ec query ok,%s running _Q%02X", Data ? "" : " not", Data);
656     if (Data == 0)
657 	return;
658 
659     /* Evaluate _Qxx to respond to the controller. */
660     snprintf(qxx, sizeof(qxx), "_Q%02X", Data);
661     AcpiUtStrupr(qxx);
662     Status = AcpiEvaluateObject(sc->ec_handle, qxx, NULL, NULL);
663     if (ACPI_FAILURE(Status) && Status != AE_NOT_FOUND) {
664 	device_printf(sc->ec_dev, "evaluation of query method %s failed: %s\n",
665 	    qxx, AcpiFormatException(Status));
666     }
667 }
668 
669 /*
670  * The GPE handler is called when IBE/OBF or SCI events occur.  We are
671  * called from an unknown lock context.
672  */
673 static uint32_t
674 EcGpeHandler(void *Context)
675 {
676     struct acpi_ec_softc *sc = Context;
677     ACPI_STATUS		       Status;
678     EC_STATUS		       EcStatus;
679 
680     KASSERT(Context != NULL, ("EcGpeHandler called with NULL"));
681     CTR0(KTR_ACPI, "ec gpe handler start");
682 
683     /*
684      * Notify EcWaitEvent() that the status register is now fresh.  If we
685      * didn't do this, it wouldn't be possible to distinguish an old IBE
686      * from a new one, for example when doing a write transaction (writing
687      * address and then data values.)
688      */
689     atomic_add_int(&sc->ec_gencount, 1);
690     wakeup(&sc->ec_gencount);
691 
692     /*
693      * If the EC_SCI bit of the status register is set, queue a query handler.
694      * It will run the query and _Qxx method later, under the lock.
695      */
696     EcStatus = EC_GET_CSR(sc);
697     if ((EcStatus & EC_EVENT_SCI) && !sc->ec_sci_pend) {
698 	CTR0(KTR_ACPI, "ec gpe queueing query handler");
699 	Status = AcpiOsExecute(OSL_GPE_HANDLER, EcGpeQueryHandler, Context);
700 	if (ACPI_SUCCESS(Status))
701 	    sc->ec_sci_pend = TRUE;
702 	else
703 	    printf("EcGpeHandler: queuing GPE query handler failed\n");
704     }
705     return (0);
706 }
707 
708 static ACPI_STATUS
709 EcSpaceSetup(ACPI_HANDLE Region, UINT32 Function, void *Context,
710 	     void **RegionContext)
711 {
712 
713     ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__);
714 
715     /*
716      * If deactivating a region, always set the output to NULL.  Otherwise,
717      * just pass the context through.
718      */
719     if (Function == ACPI_REGION_DEACTIVATE)
720 	*RegionContext = NULL;
721     else
722 	*RegionContext = Context;
723 
724     return_ACPI_STATUS (AE_OK);
725 }
726 
727 static ACPI_STATUS
728 EcSpaceHandler(UINT32 Function, ACPI_PHYSICAL_ADDRESS Address, UINT32 width,
729 	       ACPI_INTEGER *Value, void *Context, void *RegionContext)
730 {
731     struct acpi_ec_softc	*sc = (struct acpi_ec_softc *)Context;
732     ACPI_STATUS			Status;
733     UINT8			EcAddr, EcData;
734     int				i;
735 
736     ACPI_FUNCTION_TRACE_U32((char *)(uintptr_t)__func__, (UINT32)Address);
737 
738     if (width % 8 != 0 || Value == NULL || Context == NULL)
739 	return_ACPI_STATUS (AE_BAD_PARAMETER);
740     if (Address + (width / 8) - 1 > 0xFF)
741 	return_ACPI_STATUS (AE_BAD_ADDRESS);
742 
743     if (Function == ACPI_READ)
744 	*Value = 0;
745     EcAddr = Address;
746     Status = AE_ERROR;
747 
748     /*
749      * If booting, check if we need to run the query handler.  If so, we
750      * we call it directly here since our thread taskq is not active yet.
751      */
752     if (cold || rebooting || sc->ec_suspending) {
753 	if ((EC_GET_CSR(sc) & EC_EVENT_SCI)) {
754 	    CTR0(KTR_ACPI, "ec running gpe handler directly");
755 	    EcGpeQueryHandler(sc);
756 	}
757     }
758 
759     /* Serialize with EcGpeQueryHandler() at transaction granularity. */
760     Status = EcLock(sc);
761     if (ACPI_FAILURE(Status))
762 	return_ACPI_STATUS (Status);
763 
764     /* Perform the transaction(s), based on width. */
765     for (i = 0; i < width; i += 8, EcAddr++) {
766 	switch (Function) {
767 	case ACPI_READ:
768 	    Status = EcRead(sc, EcAddr, &EcData);
769 	    if (ACPI_SUCCESS(Status))
770 		*Value |= ((ACPI_INTEGER)EcData) << i;
771 	    break;
772 	case ACPI_WRITE:
773 	    EcData = (UINT8)((*Value) >> i);
774 	    Status = EcWrite(sc, EcAddr, &EcData);
775 	    break;
776 	default:
777 	    device_printf(sc->ec_dev, "invalid EcSpaceHandler function %d\n",
778 			  Function);
779 	    Status = AE_BAD_PARAMETER;
780 	    break;
781 	}
782 	if (ACPI_FAILURE(Status))
783 	    break;
784     }
785 
786     EcUnlock(sc);
787     return_ACPI_STATUS (Status);
788 }
789 
790 static ACPI_STATUS
791 EcCheckStatus(struct acpi_ec_softc *sc, const char *msg, EC_EVENT event)
792 {
793     ACPI_STATUS status;
794     EC_STATUS ec_status;
795 
796     status = AE_NO_HARDWARE_RESPONSE;
797     ec_status = EC_GET_CSR(sc);
798     if (sc->ec_burstactive && !(ec_status & EC_FLAG_BURST_MODE)) {
799 	CTR1(KTR_ACPI, "ec burst disabled in waitevent (%s)", msg);
800 	sc->ec_burstactive = FALSE;
801     }
802     if (EVENT_READY(event, ec_status)) {
803 	CTR2(KTR_ACPI, "ec %s wait ready, status %#x", msg, ec_status);
804 	status = AE_OK;
805     }
806     return (status);
807 }
808 
809 static ACPI_STATUS
810 EcWaitEvent(struct acpi_ec_softc *sc, EC_EVENT Event, u_int gen_count)
811 {
812     ACPI_STATUS	Status;
813     int		count, i, slp_ival;
814 
815     ACPI_SERIAL_ASSERT(ec);
816     Status = AE_NO_HARDWARE_RESPONSE;
817     int need_poll = cold || rebooting || ec_polled_mode || sc->ec_suspending;
818     /*
819      * The main CPU should be much faster than the EC.  So the status should
820      * be "not ready" when we start waiting.  But if the main CPU is really
821      * slow, it's possible we see the current "ready" response.  Since that
822      * can't be distinguished from the previous response in polled mode,
823      * this is a potential issue.  We really should have interrupts enabled
824      * during boot so there is no ambiguity in polled mode.
825      *
826      * If this occurs, we add an additional delay before actually entering
827      * the status checking loop, hopefully to allow the EC to go to work
828      * and produce a non-stale status.
829      */
830     if (need_poll) {
831 	static int	once;
832 
833 	if (EcCheckStatus(sc, "pre-check", Event) == AE_OK) {
834 	    if (!once) {
835 		device_printf(sc->ec_dev,
836 		    "warning: EC done before starting event wait\n");
837 		once = 1;
838 	    }
839 	    AcpiOsStall(10);
840 	}
841     }
842 
843     /* Wait for event by polling or GPE (interrupt). */
844     if (need_poll) {
845 	count = (ec_timeout * 1000) / EC_POLL_DELAY;
846 	if (count == 0)
847 	    count = 1;
848 	for (i = 0; i < count; i++) {
849 	    Status = EcCheckStatus(sc, "poll", Event);
850 	    if (Status == AE_OK)
851 		break;
852 	    AcpiOsStall(EC_POLL_DELAY);
853 	}
854     } else {
855 	slp_ival = hz / 1000;
856 	if (slp_ival != 0) {
857 	    count = ec_timeout;
858 	} else {
859 	    /* hz has less than 1 ms resolution so scale timeout. */
860 	    slp_ival = 1;
861 	    count = ec_timeout / (1000 / hz);
862 	}
863 
864 	/*
865 	 * Wait for the GPE to signal the status changed, checking the
866 	 * status register each time we get one.  It's possible to get a
867 	 * GPE for an event we're not interested in here (i.e., SCI for
868 	 * EC query).
869 	 */
870 	for (i = 0; i < count; i++) {
871 	    if (gen_count != sc->ec_gencount) {
872 		/*
873 		 * Record new generation count.  It's possible the GPE was
874 		 * just to notify us that a query is needed and we need to
875 		 * wait for a second GPE to signal the completion of the
876 		 * event we are actually waiting for.
877 		 */
878 		gen_count = sc->ec_gencount;
879 		Status = EcCheckStatus(sc, "sleep", Event);
880 		if (Status == AE_OK)
881 		    break;
882 	    }
883 	    tsleep(&sc->ec_gencount, PZERO, "ecgpe", slp_ival);
884 	}
885 
886 	/*
887 	 * We finished waiting for the GPE and it never arrived.  Try to
888 	 * read the register once and trust whatever value we got.  This is
889 	 * the best we can do at this point.  Then, force polled mode on
890 	 * since this system doesn't appear to generate GPEs.
891 	 */
892 	if (Status != AE_OK) {
893 	    Status = EcCheckStatus(sc, "sleep_end", Event);
894 	    device_printf(sc->ec_dev,
895 		"wait timed out (%sresponse), forcing polled mode\n",
896 		Status == AE_OK ? "" : "no ");
897 	    ec_polled_mode = TRUE;
898 	}
899     }
900     if (Status != AE_OK)
901 	    CTR0(KTR_ACPI, "error: ec wait timed out");
902     return (Status);
903 }
904 
905 static ACPI_STATUS
906 EcCommand(struct acpi_ec_softc *sc, EC_COMMAND cmd)
907 {
908     ACPI_STATUS	status;
909     EC_EVENT	event;
910     EC_STATUS	ec_status;
911     u_int	gen_count;
912 
913     ACPI_SERIAL_ASSERT(ec);
914 
915     /* Don't use burst mode if user disabled it. */
916     if (!ec_burst_mode && cmd == EC_COMMAND_BURST_ENABLE)
917 	return (AE_ERROR);
918 
919     /* Decide what to wait for based on command type. */
920     switch (cmd) {
921     case EC_COMMAND_READ:
922     case EC_COMMAND_WRITE:
923     case EC_COMMAND_BURST_DISABLE:
924 	event = EC_EVENT_INPUT_BUFFER_EMPTY;
925 	break;
926     case EC_COMMAND_QUERY:
927     case EC_COMMAND_BURST_ENABLE:
928 	event = EC_EVENT_OUTPUT_BUFFER_FULL;
929 	break;
930     default:
931 	device_printf(sc->ec_dev, "EcCommand: invalid command %#x\n", cmd);
932 	return (AE_BAD_PARAMETER);
933     }
934 
935     /* Run the command and wait for the chosen event. */
936     CTR1(KTR_ACPI, "ec running command %#x", cmd);
937     gen_count = sc->ec_gencount;
938     EC_SET_CSR(sc, cmd);
939     status = EcWaitEvent(sc, event, gen_count);
940     if (ACPI_SUCCESS(status)) {
941 	/* If we succeeded, burst flag should now be present. */
942 	if (cmd == EC_COMMAND_BURST_ENABLE) {
943 	    ec_status = EC_GET_CSR(sc);
944 	    if ((ec_status & EC_FLAG_BURST_MODE) == 0)
945 		status = AE_ERROR;
946 	}
947     } else
948 	device_printf(sc->ec_dev, "EcCommand: no response to %#x\n", cmd);
949     return (status);
950 }
951 
952 static ACPI_STATUS
953 EcRead(struct acpi_ec_softc *sc, UINT8 Address, UINT8 *Data)
954 {
955     ACPI_STATUS	status;
956     UINT8 data;
957     u_int gen_count;
958 
959     ACPI_SERIAL_ASSERT(ec);
960     CTR1(KTR_ACPI, "ec read from %#x", Address);
961 
962     /* If we can't start burst mode, continue anyway. */
963     status = EcCommand(sc, EC_COMMAND_BURST_ENABLE);
964     if (status == AE_OK) {
965     	data = EC_GET_DATA(sc);
966 	if (data == EC_BURST_ACK) {
967 	    CTR0(KTR_ACPI, "ec burst enabled");
968 	    sc->ec_burstactive = TRUE;
969 	}
970     }
971 
972     status = EcCommand(sc, EC_COMMAND_READ);
973     if (ACPI_FAILURE(status))
974 	return (status);
975 
976     gen_count = sc->ec_gencount;
977     EC_SET_DATA(sc, Address);
978     status = EcWaitEvent(sc, EC_EVENT_OUTPUT_BUFFER_FULL, gen_count);
979     if (ACPI_FAILURE(status)) {
980 	device_printf(sc->ec_dev, "EcRead: failed waiting to get data\n");
981 	return (status);
982     }
983     *Data = EC_GET_DATA(sc);
984 
985     if (sc->ec_burstactive) {
986 	sc->ec_burstactive = FALSE;
987 	status = EcCommand(sc, EC_COMMAND_BURST_DISABLE);
988 	if (ACPI_FAILURE(status))
989 	    return (status);
990 	CTR0(KTR_ACPI, "ec disabled burst ok");
991     }
992 
993     return (AE_OK);
994 }
995 
996 static ACPI_STATUS
997 EcWrite(struct acpi_ec_softc *sc, UINT8 Address, UINT8 *Data)
998 {
999     ACPI_STATUS	status;
1000     UINT8 data;
1001     u_int gen_count;
1002 
1003     ACPI_SERIAL_ASSERT(ec);
1004     CTR2(KTR_ACPI, "ec write to %#x, data %#x", Address, *Data);
1005 
1006     /* If we can't start burst mode, continue anyway. */
1007     status = EcCommand(sc, EC_COMMAND_BURST_ENABLE);
1008     if (status == AE_OK) {
1009     	data = EC_GET_DATA(sc);
1010 	if (data == EC_BURST_ACK) {
1011 	    CTR0(KTR_ACPI, "ec burst enabled");
1012 	    sc->ec_burstactive = TRUE;
1013 	}
1014     }
1015 
1016     status = EcCommand(sc, EC_COMMAND_WRITE);
1017     if (ACPI_FAILURE(status))
1018 	return (status);
1019 
1020     gen_count = sc->ec_gencount;
1021     EC_SET_DATA(sc, Address);
1022     status = EcWaitEvent(sc, EC_EVENT_INPUT_BUFFER_EMPTY, gen_count);
1023     if (ACPI_FAILURE(status)) {
1024 	device_printf(sc->ec_dev, "EcRead: failed waiting for sent address\n");
1025 	return (status);
1026     }
1027 
1028     gen_count = sc->ec_gencount;
1029     EC_SET_DATA(sc, *Data);
1030     status = EcWaitEvent(sc, EC_EVENT_INPUT_BUFFER_EMPTY, gen_count);
1031     if (ACPI_FAILURE(status)) {
1032 	device_printf(sc->ec_dev, "EcWrite: failed waiting for sent data\n");
1033 	return (status);
1034     }
1035 
1036     if (sc->ec_burstactive) {
1037 	sc->ec_burstactive = FALSE;
1038 	status = EcCommand(sc, EC_COMMAND_BURST_DISABLE);
1039 	if (ACPI_FAILURE(status))
1040 	    return (status);
1041 	CTR0(KTR_ACPI, "ec disabled burst ok");
1042     }
1043 
1044     return (AE_OK);
1045 }
1046