xref: /freebsd/sys/dev/acpica/acpi_cmbat.c (revision eacee0ff7ec955b32e09515246bd97b6edcd2b0f)
1 /*-
2  * Copyright (c) 2000 Munehiro Matsuda
3  * Copyright (c) 2000 Takanori Watanabe
4  * Copyright (c) 2000 Mitsuru IWASAKI <iwasaki@FreeBSD.org>
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  * $FreeBSD$
29  */
30 
31 #include "opt_acpi.h"
32 #include <sys/param.h>
33 #include <sys/kernel.h>
34 #include <sys/bus.h>
35 #include <sys/ioccom.h>
36 #include <sys/conf.h>
37 
38 #include <machine/bus.h>
39 #include <machine/resource.h>
40 #include <sys/rman.h>
41 #include <sys/malloc.h>
42 
43 #include  "acpi.h"
44 
45 #include <dev/acpica/acpivar.h>
46 #include <dev/acpica/acpiio.h>
47 
48 MALLOC_DEFINE(M_ACPICMBAT, "acpicmbat", "ACPI control method battery data");
49 
50 #define	CMBAT_POLLRATE	(60 * hz)
51 
52 /*
53  * Hooks for the ACPI CA debugging infrastructure
54  */
55 #define	_COMPONENT	ACPI_BATTERY
56 MODULE_NAME("BATTERY")
57 
58 #define	ACPI_BATTERY_BST_CHANGE 0x80
59 #define	ACPI_BATTERY_BIF_CHANGE 0x81
60 
61 #define	PKG_GETINT(res, tmp, idx, dest, label) do {			\
62 	tmp = &res->Package.Elements[idx];				\
63 	if (tmp == NULL) {						\
64 		ACPI_VPRINT(dev, acpi_device_get_parent_softc(dev),	\
65 		    __func__ ": PKG_GETINT error, idx = %d\n.", idx);	\
66 		goto label;						\
67 	}								\
68 	if (tmp->Type != ACPI_TYPE_INTEGER)				\
69 		goto label;						\
70 	dest = tmp->Integer.Value;					\
71 } while (0)
72 
73 #define	PKG_GETSTR(res, tmp, idx, dest, size, label) do {              	\
74 	size_t	length;							\
75 	length = size;							\
76 	tmp = &res->Package.Elements[idx]; 				\
77 	if (tmp == NULL) {						\
78 		ACPI_VPRINT(dev, acpi_device_get_parent_softc(dev),	\
79 		    __func__ ": PKG_GETSTR error, idx = %d\n.", idx);	\
80 		goto label;						\
81 	}								\
82 	bzero(dest, sizeof(dest));					\
83 	switch (tmp->Type) {						\
84 	case ACPI_TYPE_STRING:						\
85 		if (tmp->String.Length < length) {			\
86 			length = tmp->String.Length;			\
87 		}							\
88 		strncpy(dest, tmp->String.Pointer, length);		\
89 		break;							\
90 	case ACPI_TYPE_BUFFER:						\
91 		if (tmp->Buffer.Length < length) {			\
92 			length = tmp->Buffer.Length;			\
93 		}							\
94 		strncpy(dest, tmp->Buffer.Pointer, length);		\
95 		break;							\
96 	default:							\
97 		goto label;						\
98 	}								\
99 	dest[sizeof(dest)-1] = '\0';					\
100 } while (0)
101 
102 struct acpi_cmbat_softc {
103 	device_t	dev;
104 
105 	struct acpi_bif	bif;
106 	struct acpi_bst	bst;
107 	ACPI_BUFFER	bif_buffer;
108 	ACPI_BUFFER	bst_buffer;
109 	struct timespec	bif_lastupdated;
110 	struct timespec	bst_lastupdated;
111 	int		bif_updating;
112 	int		bst_updating;
113 
114 	int		not_present;
115 	int		cap;
116 	int		min;
117 	int		full_charge_time;
118 
119 	struct callout_handle cmbat_timeout;
120 };
121 
122 static struct timespec	 acpi_cmbat_info_lastupdated;
123 
124 /* XXX: devclass_get_maxunit() don't give us the current allocated units... */
125 static int		 acpi_cmbat_units = 0;
126 
127 static void		 acpi_cmbat_timeout(void *);
128 static int		 acpi_cmbat_info_expired(struct timespec *);
129 static void		 acpi_cmbat_info_updated(struct timespec *);
130 static void		 acpi_cmbat_get_bst(void *);
131 static void		 acpi_cmbat_get_bif(void *);
132 static void		 acpi_cmbat_notify_handler(ACPI_HANDLE, UINT32, void *);
133 static int		 acpi_cmbat_probe(device_t);
134 static int		 acpi_cmbat_attach(device_t);
135 static int		 acpi_cmbat_resume(device_t);
136 static int		 acpi_cmbat_ioctl(u_long, caddr_t, void *);
137 static int		 acpi_cmbat_get_total_battinfo(struct acpi_battinfo *);
138 
139 /*
140  * Poll the battery info.
141  */
142 static void
143 acpi_cmbat_timeout(void *context)
144 {
145 	device_t	dev;
146 	struct acpi_cmbat_softc *sc;
147 
148 	dev = (device_t)context;
149 	sc = device_get_softc(dev);
150 
151 	AcpiOsQueueForExecution(OSD_PRIORITY_LO, acpi_cmbat_get_bif, dev);
152 	sc->cmbat_timeout = timeout(acpi_cmbat_timeout, dev, CMBAT_POLLRATE);
153 }
154 
155 static __inline int
156 acpi_cmbat_info_expired(struct timespec *lastupdated)
157 {
158 	struct timespec	curtime;
159 
160 	if (lastupdated == NULL) {
161 		return (1);
162 	}
163 
164 	if (!timespecisset(lastupdated)) {
165 		return (1);
166 	}
167 
168 	getnanotime(&curtime);
169 	timespecsub(&curtime, lastupdated);
170 	return ((curtime.tv_sec < 0 || curtime.tv_sec > acpi_battery_get_info_expire()));
171 }
172 
173 
174 static __inline void
175 acpi_cmbat_info_updated(struct timespec *lastupdated)
176 {
177 
178 	if (lastupdated != NULL) {
179 		getnanotime(lastupdated);
180 	}
181 }
182 
183 static void
184 acpi_cmbat_get_bst(void *context)
185 {
186 	device_t	dev;
187 	struct acpi_cmbat_softc *sc;
188 	ACPI_STATUS	as;
189 	ACPI_OBJECT	*res, *tmp;
190 	ACPI_HANDLE	h;
191 
192 	dev = context;
193 	sc = device_get_softc(dev);
194 	h = acpi_get_handle(dev);
195 
196 	if (!acpi_cmbat_info_expired(&sc->bst_lastupdated)) {
197 		return;
198 	}
199 
200 	if (sc->bst_updating) {
201 		return;
202 	}
203 	sc->bst_updating = 1;
204 
205 	untimeout(acpi_cmbat_timeout, (caddr_t)dev, sc->cmbat_timeout);
206 
207 	if ((as = acpi_EvaluateIntoBuffer(h, "_BST", NULL, &sc->bst_buffer)) != AE_OK) {
208 		ACPI_VPRINT(dev, acpi_device_get_parent_softc(dev),
209 		    "error fetching current battery status -- %s\n",
210 		    AcpiFormatException(as));
211 		goto end;
212 	}
213 
214 	res = (ACPI_OBJECT *)sc->bst_buffer.Pointer;
215 
216 	if ((res->Type != ACPI_TYPE_PACKAGE) || (res->Package.Count != 4)) {
217 		ACPI_VPRINT(dev, acpi_device_get_parent_softc(dev),
218 		    "battery status corrupted\n");
219 		goto end;
220 	}
221 
222 	PKG_GETINT(res, tmp, 0, sc->bst.state, end);
223 	PKG_GETINT(res, tmp, 1, sc->bst.rate, end);
224 	PKG_GETINT(res, tmp, 2, sc->bst.cap, end);
225 	PKG_GETINT(res, tmp, 3, sc->bst.volt, end);
226 	acpi_cmbat_info_updated(&sc->bst_lastupdated);
227 end:
228 	sc->bst_updating = 0;
229 	sc->cmbat_timeout = timeout(acpi_cmbat_timeout, dev, CMBAT_POLLRATE);
230 }
231 
232 static void
233 acpi_cmbat_get_bif(void *context)
234 {
235 	device_t	dev;
236 	struct acpi_cmbat_softc *sc;
237 	ACPI_STATUS	as;
238 	ACPI_OBJECT	*res, *tmp;
239 	ACPI_HANDLE	h;
240 
241 	dev = context;
242 	sc = device_get_softc(dev);
243 	h = acpi_get_handle(dev);
244 
245 	if (!acpi_cmbat_info_expired(&sc->bif_lastupdated)) {
246 		return;
247 	}
248 
249 	if (sc->bif_updating) {
250 		return;
251 	}
252 	sc->bif_updating = 1;
253 
254 	untimeout(acpi_cmbat_timeout, (caddr_t)dev, sc->cmbat_timeout);
255 
256 	if ((as = acpi_EvaluateIntoBuffer(h, "_BIF", NULL, &sc->bif_buffer)) != AE_OK) {
257 		ACPI_VPRINT(dev, acpi_device_get_parent_softc(dev),
258 		    "error fetching current battery info -- %s\n",
259 		    AcpiFormatException(as));
260 		goto end;
261 	}
262 
263 	res = (ACPI_OBJECT *)sc->bif_buffer.Pointer;
264 
265 	if ((res->Type != ACPI_TYPE_PACKAGE) || (res->Package.Count != 13)) {
266 		ACPI_VPRINT(dev, acpi_device_get_parent_softc(dev),
267 		    "battery info corrupted\n");
268 		goto end;
269 	}
270 
271 	PKG_GETINT(res, tmp,  0, sc->bif.unit, end);
272 	PKG_GETINT(res, tmp,  1, sc->bif.dcap, end);
273 	PKG_GETINT(res, tmp,  2, sc->bif.lfcap, end);
274 	PKG_GETINT(res, tmp,  3, sc->bif.btech, end);
275 	PKG_GETINT(res, tmp,  4, sc->bif.dvol, end);
276 	PKG_GETINT(res, tmp,  5, sc->bif.wcap, end);
277 	PKG_GETINT(res, tmp,  6, sc->bif.lcap, end);
278 	PKG_GETINT(res, tmp,  7, sc->bif.gra1, end);
279 	PKG_GETINT(res, tmp,  8, sc->bif.gra2, end);
280 	PKG_GETSTR(res, tmp,  9, sc->bif.model, ACPI_CMBAT_MAXSTRLEN, end);
281 	PKG_GETSTR(res, tmp, 10, sc->bif.serial, ACPI_CMBAT_MAXSTRLEN, end);
282 	PKG_GETSTR(res, tmp, 11, sc->bif.type, ACPI_CMBAT_MAXSTRLEN, end);
283 	PKG_GETSTR(res, tmp, 12, sc->bif.oeminfo, ACPI_CMBAT_MAXSTRLEN, end);
284 	acpi_cmbat_info_updated(&sc->bif_lastupdated);
285 end:
286 	sc->bif_updating = 0;
287 	sc->cmbat_timeout = timeout(acpi_cmbat_timeout, dev, CMBAT_POLLRATE);
288 }
289 
290 static void
291 acpi_cmbat_notify_handler(ACPI_HANDLE h, UINT32 notify, void *context)
292 {
293 	device_t	dev;
294 	struct acpi_cmbat_softc	*sc;
295 
296 	dev = (device_t)context;
297 	if ((sc = device_get_softc(dev)) == NULL) {
298 		return;
299 	}
300 
301 	switch (notify) {
302 	case ACPI_BATTERY_BST_CHANGE:
303 		timespecclear(&sc->bst_lastupdated);
304 		break;
305 	case ACPI_BATTERY_BIF_CHANGE:
306 		timespecclear(&sc->bif_lastupdated);
307 		AcpiOsQueueForExecution(OSD_PRIORITY_LO, acpi_cmbat_get_bif, dev);
308 		break;
309 	default:
310 		break;
311 	}
312 }
313 
314 static int
315 acpi_cmbat_probe(device_t dev)
316 {
317 
318 	if ((acpi_get_type(dev) == ACPI_TYPE_DEVICE) &&
319 	    !acpi_disabled("cmbat") &&
320 	    acpi_MatchHid(dev, "PNP0C0A")) {
321 		/*
322 		 * Set device description.
323 		 */
324 		device_set_desc(dev, "Control method Battery");
325 		return (0);
326 	}
327 	return (ENXIO);
328 }
329 
330 static int
331 acpi_cmbat_attach(device_t dev)
332 {
333 	int		error;
334 	ACPI_HANDLE	handle;
335 	struct acpi_cmbat_softc *sc;
336 
337 	if ((sc = device_get_softc(dev)) == NULL) {
338 		return (ENXIO);
339 	}
340 
341 	handle = acpi_get_handle(dev);
342 
343 	AcpiInstallNotifyHandler(handle, ACPI_DEVICE_NOTIFY,
344 				 acpi_cmbat_notify_handler, dev);
345 
346 	bzero(&sc->bif_buffer, sizeof(sc->bif_buffer));
347 	bzero(&sc->bst_buffer, sizeof(sc->bst_buffer));
348 	sc->bif_updating = sc->bst_updating = 0;
349 	sc->dev = dev;
350 
351 	timespecclear(&sc->bif_lastupdated);
352 	timespecclear(&sc->bst_lastupdated);
353 
354 	if (acpi_cmbat_units == 0) {
355 		if ((error = acpi_register_ioctl(ACPIIO_CMBAT_GET_BIF,
356 				acpi_cmbat_ioctl, NULL)) != 0) {
357 			return (error);
358 		}
359 		if ((error = acpi_register_ioctl(ACPIIO_CMBAT_GET_BST,
360 				acpi_cmbat_ioctl, NULL)) != 0) {
361 			return (error);
362 		}
363 	}
364 
365 	if ((error = acpi_battery_register(ACPI_BATT_TYPE_CMBAT,
366 			acpi_cmbat_units)) != 0) {
367 		return (error);
368 	}
369 
370 	acpi_cmbat_units++;
371 	timespecclear(&acpi_cmbat_info_lastupdated);
372 
373 	AcpiOsQueueForExecution(OSD_PRIORITY_LO, acpi_cmbat_get_bif, dev);
374 	return (0);
375 }
376 
377 static int
378 acpi_cmbat_resume(device_t dev)
379 {
380 
381 	AcpiOsQueueForExecution(OSD_PRIORITY_LO, acpi_cmbat_get_bif, dev);
382 	return (0);
383 }
384 
385 static device_method_t acpi_cmbat_methods[] = {
386 	/* Device interface */
387 	DEVMETHOD(device_probe,		acpi_cmbat_probe),
388 	DEVMETHOD(device_attach,	acpi_cmbat_attach),
389 	DEVMETHOD(device_resume,	acpi_cmbat_resume),
390 
391 	{0, 0}
392 };
393 
394 static driver_t acpi_cmbat_driver = {
395 	"acpi_cmbat",
396 	acpi_cmbat_methods,
397 	sizeof(struct acpi_cmbat_softc),
398 };
399 
400 static devclass_t acpi_cmbat_devclass;
401 DRIVER_MODULE(acpi_cmbat, acpi, acpi_cmbat_driver, acpi_cmbat_devclass, 0, 0);
402 
403 static int
404 acpi_cmbat_ioctl(u_long cmd, caddr_t addr, void *arg)
405 {
406 	device_t	dev;
407 	union acpi_battery_ioctl_arg *ioctl_arg;
408 	struct acpi_cmbat_softc *sc;
409 	struct acpi_bif	*bifp;
410 	struct acpi_bst	*bstp;
411 
412 	ioctl_arg = (union acpi_battery_ioctl_arg *)addr;
413 	if ((dev = devclass_get_device(acpi_cmbat_devclass,
414 			ioctl_arg->unit)) == NULL) {
415 		return (ENXIO);
416 	}
417 
418 	if ((sc = device_get_softc(dev)) == NULL) {
419 		return (ENXIO);
420 	}
421 
422 	switch (cmd) {
423 	case ACPIIO_CMBAT_GET_BIF:
424 		acpi_cmbat_get_bif(dev);
425 		bifp = &ioctl_arg->bif;
426 		bifp->unit = sc->bif.unit;
427 		bifp->dcap = sc->bif.dcap;
428 		bifp->lfcap = sc->bif.lfcap;
429 		bifp->btech = sc->bif.btech;
430 		bifp->dvol = sc->bif.dvol;
431 		bifp->wcap = sc->bif.wcap;
432 		bifp->lcap = sc->bif.lcap;
433 		bifp->gra1 = sc->bif.gra1;
434 		bifp->gra2 = sc->bif.gra2;
435 		strncpy(bifp->model, sc->bif.model, sizeof(sc->bif.model));
436 		strncpy(bifp->serial, sc->bif.serial, sizeof(sc->bif.serial));
437 		strncpy(bifp->type, sc->bif.type, sizeof(sc->bif.type));
438 		strncpy(bifp->oeminfo, sc->bif.oeminfo, sizeof(sc->bif.oeminfo));
439 		break;
440 
441 	case ACPIIO_CMBAT_GET_BST:
442 		acpi_cmbat_get_bst(dev);
443 		bstp = &ioctl_arg->bst;
444 		bstp->state = sc->bst.state;
445 		bstp->rate = sc->bst.rate;
446 		bstp->cap = sc->bst.cap;
447 		bstp->volt = sc->bst.volt;
448 		break;
449 	}
450 
451 	return (0);
452 }
453 
454 static int
455 acpi_cmbat_get_total_battinfo(struct acpi_battinfo *battinfo)
456 {
457 	int		i;
458 	int		error;
459 	int		batt_stat;
460 	int		valid_rate, valid_units;
461 	int		cap, min;
462 	int		total_cap, total_min, total_full;
463 	device_t	dev;
464 	struct acpi_cmbat_softc *sc;
465 	static int	bat_units = 0;
466 	static struct acpi_cmbat_softc **bat = NULL;
467 
468 	cap = min = -1;
469 	batt_stat = ACPI_BATT_STAT_NOT_PRESENT;
470 	error = 0;
471 
472 	/* Allocate array of softc pointers */
473 	if (bat_units != acpi_cmbat_units) {
474 		if (bat != NULL) {
475 			free(bat, M_ACPICMBAT);
476 			bat = NULL;
477 		}
478 		bat_units = 0;
479 	}
480 	if (bat == NULL) {
481 		bat_units = acpi_cmbat_units;
482 		bat = malloc(sizeof(struct acpi_cmbat_softc *) * bat_units,
483 			     M_ACPICMBAT, M_NOWAIT);
484 		if (bat == NULL) {
485 			error = ENOMEM;
486 			goto out;
487 		}
488 
489 		/* Collect softc pointers */
490 		for (i = 0; i < acpi_cmbat_units; i++) {
491 			if ((dev = devclass_get_device(acpi_cmbat_devclass, i)) == NULL) {
492 				error = ENXIO;
493 				goto out;
494 			}
495 
496 			if ((sc = device_get_softc(dev)) == NULL) {
497 				error = ENXIO;
498 				goto out;
499 			}
500 
501 			bat[i] = sc;
502 		}
503 	}
504 
505 	/* Get battery status, valid rate and valid units */
506 	batt_stat = valid_rate = valid_units = 0;
507 	for (i = 0; i < acpi_cmbat_units; i++) {
508 		bat[i]->not_present = 0;
509 		acpi_cmbat_get_bst(bat[i]->dev);
510 
511 		/* If battey not installed, we get strange values */
512 		if (bat[i]->bst.state >= ACPI_BATT_STAT_MAX ||
513 		    bat[i]->bst.cap == 0xffffffff ||
514 		    bat[i]->bst.volt == 0xffffffff ||
515 		    bat[i]->bif.lfcap == 0) {
516 			bat[i]->not_present = 1;
517 			continue;
518 		}
519 
520 		valid_units++;
521 
522 		bat[i]->cap = 100 * bat[i]->bst.cap / bat[i]->bif.lfcap;
523 
524 		batt_stat |= bat[i]->bst.state;
525 
526 		if (bat[i]->bst.rate > 0) {
527 			/*
528 			 * XXX Hack to calculate total battery time.
529 			 * Systems with 2 or more battries, they may get used
530 			 * one by one, thus bst.rate is set only to the one
531 			 * in use. For remaining batteries bst.rate = 0, which
532 			 * makes it impossible to calculate remaining time.
533 			 * Some other systems may need sum of bst.rate in
534 			 * dis-charging state.
535 			 * There for we sum up the bst.rate that is valid
536 			 * (in dis-charging state), and use the sum to
537 			 * calcutate remaining batteries' time.
538 			 */
539 			if (bat[i]->bst.state & ACPI_BATT_STAT_DISCHARG) {
540 				valid_rate += bat[i]->bst.rate;
541 			}
542 		}
543 	}
544 
545 	/* Calculate total battery capacity and time */
546 	total_cap = total_min = total_full = 0;
547 	for (i = 0; i < acpi_cmbat_units; i++) {
548 		if (bat[i]->not_present) {
549 			continue;
550 		}
551 
552 		if (valid_rate > 0) {
553 			/* Use the sum of bst.rate */
554 			bat[i]->min = 60 * bat[i]->bst.cap / valid_rate;
555 		} else if (bat[i]->full_charge_time > 0) {
556 			bat[i]->min = (bat[i]->full_charge_time * bat[i]->cap) / 100;
557 		} else {
558 			/* Couldn't find valid rate and full battery time */
559 			bat[i]->min = 0;
560 		}
561 		total_min += bat[i]->min;
562 		total_cap += bat[i]->cap;
563 		total_full += bat[i]->full_charge_time;
564 	}
565 
566 	/* Battery life */
567 	if (valid_units == 0) {
568 		cap = -1;
569 		batt_stat = ACPI_BATT_STAT_NOT_PRESENT;
570 	} else {
571 		cap = total_cap / valid_units;
572 	}
573 
574 	/* Battery time */
575 	if (valid_units == 0) {
576 		min = -1;
577 	} else if (valid_rate == 0 || (batt_stat & ACPI_BATT_STAT_CHARGING)) {
578 		if (total_full == 0) {
579 			min = -1;
580 		} else {
581 			min = (total_full * cap) / 100;
582 		}
583 	} else {
584 		min = total_min;
585 	}
586 
587 	acpi_cmbat_info_updated(&acpi_cmbat_info_lastupdated);
588 out:
589 	battinfo->cap = cap;
590 	battinfo->min = min;
591 	battinfo->state = batt_stat;
592 
593 	return (error);
594 }
595 
596 /*
597  * Public interfaces.
598  */
599 
600 int
601 acpi_cmbat_get_battinfo(int unit, struct acpi_battinfo *battinfo)
602 {
603 	int		error;
604 	device_t	dev;
605 	struct acpi_cmbat_softc *sc;
606 
607 	if (unit == -1) {
608 		return (acpi_cmbat_get_total_battinfo(battinfo));
609 	}
610 
611 	if (acpi_cmbat_info_expired(&acpi_cmbat_info_lastupdated)) {
612 		error = acpi_cmbat_get_total_battinfo(battinfo);
613 		if (error) {
614 			goto out;
615 		}
616 	}
617 
618 	error = 0;
619 	if (unit >= acpi_cmbat_units) {
620 		error = ENXIO;
621 		goto out;
622 	}
623 
624 	if ((dev = devclass_get_device(acpi_cmbat_devclass, unit)) == NULL) {
625 		error = ENXIO;
626 		goto out;
627 	}
628 
629 	if ((sc = device_get_softc(dev)) == NULL) {
630 		error = ENXIO;
631 		goto out;
632 	}
633 
634 	if (sc->not_present) {
635 		battinfo->cap = -1;
636 		battinfo->min = -1;
637 		battinfo->state = ACPI_BATT_STAT_NOT_PRESENT;
638 	} else {
639 		battinfo->cap = sc->cap;
640 		battinfo->min = sc->min;
641 		battinfo->state = sc->bst.state;
642 	}
643 out:
644 	return (error);
645 }
646 
647