xref: /freebsd/sys/dev/acpica/acpi_battery.c (revision d6b92ffa)
1 /*-
2  * Copyright (c) 2005 Nate Lawson
3  * Copyright (c) 2000 Mitsuru IWASAKI <iwasaki@jp.freebsd.org>
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  */
27 
28 #include <sys/cdefs.h>
29 __FBSDID("$FreeBSD$");
30 
31 #include "opt_acpi.h"
32 #include <sys/param.h>
33 #include <sys/kernel.h>
34 #include <sys/malloc.h>
35 #include <sys/bus.h>
36 #include <sys/ioccom.h>
37 #include <sys/sysctl.h>
38 
39 #include <contrib/dev/acpica/include/acpi.h>
40 
41 #include <dev/acpica/acpivar.h>
42 #include <dev/acpica/acpiio.h>
43 
44 /* Default seconds before re-sampling the battery state. */
45 #define	ACPI_BATTERY_INFO_EXPIRE	5
46 
47 static int	acpi_batteries_initted;
48 static int	acpi_battery_info_expire = ACPI_BATTERY_INFO_EXPIRE;
49 static struct	acpi_battinfo	acpi_battery_battinfo;
50 static struct	sysctl_ctx_list	acpi_battery_sysctl_ctx;
51 static struct	sysctl_oid	*acpi_battery_sysctl_tree;
52 
53 ACPI_SERIAL_DECL(battery, "ACPI generic battery");
54 
55 static void acpi_reset_battinfo(struct acpi_battinfo *info);
56 static void acpi_battery_clean_str(char *str, int len);
57 static device_t acpi_battery_find_dev(u_int logical_unit);
58 static int acpi_battery_ioctl(u_long cmd, caddr_t addr, void *arg);
59 static int acpi_battery_sysctl(SYSCTL_HANDLER_ARGS);
60 static int acpi_battery_units_sysctl(SYSCTL_HANDLER_ARGS);
61 static int acpi_battery_init(void);
62 
63 int
64 acpi_battery_register(device_t dev)
65 {
66     int error;
67 
68     error = 0;
69     ACPI_SERIAL_BEGIN(battery);
70     if (!acpi_batteries_initted)
71 	error = acpi_battery_init();
72     ACPI_SERIAL_END(battery);
73     return (error);
74 }
75 
76 int
77 acpi_battery_remove(device_t dev)
78 {
79 
80     return (0);
81 }
82 
83 int
84 acpi_battery_get_units(void)
85 {
86     devclass_t batt_dc;
87 
88     batt_dc = devclass_find("battery");
89     if (batt_dc == NULL)
90 	return (0);
91     return (devclass_get_count(batt_dc));
92 }
93 
94 int
95 acpi_battery_get_info_expire(void)
96 {
97 
98     return (acpi_battery_info_expire);
99 }
100 
101 /* Check _BST results for validity. */
102 int
103 acpi_battery_bst_valid(struct acpi_bst *bst)
104 {
105 
106     return (bst->state != ACPI_BATT_STAT_NOT_PRESENT &&
107 	bst->cap != ACPI_BATT_UNKNOWN && bst->volt != ACPI_BATT_UNKNOWN);
108 }
109 
110 /* Check _BIF results for validity. */
111 int
112 acpi_battery_bif_valid(struct acpi_bif *bif)
113 {
114     return (bif->lfcap != 0);
115 }
116 
117 /* Get info about one or all batteries. */
118 int
119 acpi_battery_get_battinfo(device_t dev, struct acpi_battinfo *battinfo)
120 {
121     int	batt_stat, devcount, dev_idx, error, i;
122     int total_cap, total_min, valid_rate, valid_units;
123     devclass_t batt_dc;
124     device_t batt_dev;
125     struct acpi_bst *bst;
126     struct acpi_bif *bif;
127     struct acpi_battinfo *bi;
128 
129     /*
130      * Get the battery devclass and max unit for battery devices.  If there
131      * are none or error, return immediately.
132      */
133     batt_dc = devclass_find("battery");
134     if (batt_dc == NULL)
135 	return (ENXIO);
136     devcount = devclass_get_maxunit(batt_dc);
137     if (devcount == 0)
138 	return (ENXIO);
139 
140     /*
141      * Allocate storage for all _BST data, their derived battinfo data,
142      * and the current battery's _BIF data.
143      */
144     bst = malloc(devcount * sizeof(*bst), M_TEMP, M_WAITOK | M_ZERO);
145     bi = malloc(devcount * sizeof(*bi), M_TEMP, M_WAITOK | M_ZERO);
146     bif = malloc(sizeof(*bif), M_TEMP, M_WAITOK | M_ZERO);
147 
148     /*
149      * Pass 1:  for each battery that is present and valid, get its status,
150      * calculate percent capacity remaining, and sum all the current
151      * discharge rates.
152      */
153     dev_idx = -1;
154     batt_stat = valid_rate = valid_units = 0;
155     for (i = 0; i < devcount; i++) {
156 	/* Default info for every battery is "not present". */
157 	acpi_reset_battinfo(&bi[i]);
158 
159 	/*
160 	 * Find the device.  Since devcount is in terms of max units, this
161 	 * may be a sparse array so skip devices that aren't present.
162 	 */
163 	batt_dev = devclass_get_device(batt_dc, i);
164 	if (batt_dev == NULL)
165 	    continue;
166 
167 	/* If examining a specific battery and this is it, record its index. */
168 	if (dev != NULL && dev == batt_dev)
169 	    dev_idx = i;
170 
171 	/*
172 	 * Be sure we can get various info from the battery.  Note that
173 	 * acpi_BatteryIsPresent() is not enough because smart batteries only
174 	 * return that the device is present.
175 	 */
176 	if (!acpi_BatteryIsPresent(batt_dev) ||
177 	    ACPI_BATT_GET_STATUS(batt_dev, &bst[i]) != 0 ||
178 	    ACPI_BATT_GET_INFO(batt_dev, bif) != 0)
179 	    continue;
180 
181 	/* If a battery is not installed, we sometimes get strange values. */
182 	if (!acpi_battery_bst_valid(&bst[i]) ||
183 	    !acpi_battery_bif_valid(bif))
184 	    continue;
185 
186 	/*
187 	 * Record current state.  If both charging and discharging are set,
188 	 * ignore the charging flag.
189 	 */
190 	valid_units++;
191 	if ((bst[i].state & ACPI_BATT_STAT_DISCHARG) != 0)
192 	    bst[i].state &= ~ACPI_BATT_STAT_CHARGING;
193 	batt_stat |= bst[i].state;
194 	bi[i].state = bst[i].state;
195 
196 	/*
197 	 * If the battery info is in terms of mA, convert to mW by
198 	 * multiplying by the design voltage.  If the design voltage
199 	 * is 0 (due to some error reading the battery), skip this
200 	 * conversion.
201 	 */
202 	if (bif->units == ACPI_BIF_UNITS_MA && bif->dvol != 0 && dev == NULL) {
203 	    bst[i].rate = (bst[i].rate * bif->dvol) / 1000;
204 	    bst[i].cap = (bst[i].cap * bif->dvol) / 1000;
205 	    bif->lfcap = (bif->lfcap * bif->dvol) / 1000;
206 	}
207 
208 	/*
209 	 * The calculation above may set bif->lfcap to zero. This was
210 	 * seen on a laptop with a broken battery. The result of the
211 	 * division was rounded to zero.
212 	 */
213 	if (!acpi_battery_bif_valid(bif))
214 	    continue;
215 
216 	/* Calculate percent capacity remaining. */
217 	bi[i].cap = (100 * bst[i].cap) / bif->lfcap;
218 
219 	/*
220 	 * Some laptops report the "design-capacity" instead of the
221 	 * "real-capacity" when the battery is fully charged.  That breaks
222 	 * the above arithmetic as it needs to be 100% maximum.
223 	 */
224 	if (bi[i].cap > 100)
225 	    bi[i].cap = 100;
226 
227 	/*
228 	 * On systems with more than one battery, they may get used
229 	 * sequentially, thus bst.rate may only signify the one currently
230 	 * in use.  For the remaining batteries, bst.rate will be zero,
231 	 * which makes it impossible to calculate the total remaining time.
232 	 * Therefore, we sum the bst.rate for batteries in the discharging
233 	 * state and use the sum to calculate the total remaining time.
234 	 */
235 	if (bst[i].rate != ACPI_BATT_UNKNOWN &&
236 	    (bst[i].state & ACPI_BATT_STAT_DISCHARG) != 0)
237 	    valid_rate += bst[i].rate;
238     }
239 
240     /* If the caller asked for a device but we didn't find it, error. */
241     if (dev != NULL && dev_idx == -1) {
242 	error = ENXIO;
243 	goto out;
244     }
245 
246     /* Pass 2:  calculate capacity and remaining time for all batteries. */
247     total_cap = total_min = 0;
248     for (i = 0; i < devcount; i++) {
249 	/*
250 	 * If any batteries are discharging, use the sum of the bst.rate
251 	 * values.  Otherwise, we are on AC power, and there is infinite
252 	 * time remaining for this battery until we go offline.
253 	 */
254 	if (valid_rate > 0)
255 	    bi[i].min = (60 * bst[i].cap) / valid_rate;
256 	else
257 	    bi[i].min = 0;
258 	total_min += bi[i].min;
259 
260 	/* If this battery is not present, don't use its capacity. */
261 	if (bi[i].cap != -1)
262 	    total_cap += bi[i].cap;
263     }
264 
265     /*
266      * Return total battery percent and time remaining.  If there are
267      * no valid batteries, report values as unknown.
268      */
269     if (valid_units > 0) {
270 	if (dev == NULL) {
271 	    battinfo->cap = total_cap / valid_units;
272 	    battinfo->min = total_min;
273 	    battinfo->state = batt_stat;
274 	    battinfo->rate = valid_rate;
275 	} else {
276 	    battinfo->cap = bi[dev_idx].cap;
277 	    battinfo->min = bi[dev_idx].min;
278 	    battinfo->state = bi[dev_idx].state;
279 	    battinfo->rate = bst[dev_idx].rate;
280 	}
281 
282 	/*
283 	 * If the queried battery has no discharge rate or is charging,
284 	 * report that we don't know the remaining time.
285 	 */
286 	if (valid_rate == 0 || (battinfo->state & ACPI_BATT_STAT_CHARGING))
287 	    battinfo->min = -1;
288     } else
289 	acpi_reset_battinfo(battinfo);
290 
291     error = 0;
292 
293 out:
294     if (bi)
295 	free(bi, M_TEMP);
296     if (bif)
297 	free(bif, M_TEMP);
298     if (bst)
299 	free(bst, M_TEMP);
300     return (error);
301 }
302 
303 static void
304 acpi_reset_battinfo(struct acpi_battinfo *info)
305 {
306     info->cap = -1;
307     info->min = -1;
308     info->state = ACPI_BATT_STAT_NOT_PRESENT;
309     info->rate = -1;
310 }
311 
312 /* Make string printable, removing invalid chars. */
313 static void
314 acpi_battery_clean_str(char *str, int len)
315 {
316     int i;
317 
318     for (i = 0; i < len && *str != '\0'; i++, str++) {
319 	if (!isprint(*str))
320 	    *str = '?';
321     }
322 
323     /* NUL-terminate the string if we reached the end. */
324     if (i == len)
325 	*str = '\0';
326 }
327 
328 /*
329  * The battery interface deals with devices and methods but userland
330  * expects a logical unit number.  Convert a logical unit to a device_t.
331  */
332 static device_t
333 acpi_battery_find_dev(u_int logical_unit)
334 {
335     int found_unit, i, maxunit;
336     device_t dev;
337     devclass_t batt_dc;
338 
339     dev = NULL;
340     found_unit = 0;
341     batt_dc = devclass_find("battery");
342     maxunit = devclass_get_maxunit(batt_dc);
343     for (i = 0; i < maxunit; i++) {
344 	dev = devclass_get_device(batt_dc, i);
345 	if (dev == NULL)
346 	    continue;
347 	if (logical_unit == found_unit)
348 	    break;
349 	found_unit++;
350 	dev = NULL;
351     }
352 
353     return (dev);
354 }
355 
356 static int
357 acpi_battery_ioctl(u_long cmd, caddr_t addr, void *arg)
358 {
359     union acpi_battery_ioctl_arg *ioctl_arg;
360     int error, unit;
361     device_t dev;
362 
363     /* For commands that use the ioctl_arg struct, validate it first. */
364     error = ENXIO;
365     unit = 0;
366     dev = NULL;
367     ioctl_arg = NULL;
368     if (IOCPARM_LEN(cmd) == sizeof(*ioctl_arg)) {
369 	ioctl_arg = (union acpi_battery_ioctl_arg *)addr;
370 	unit = ioctl_arg->unit;
371 	if (unit != ACPI_BATTERY_ALL_UNITS)
372 	    dev = acpi_battery_find_dev(unit);
373     }
374 
375     /*
376      * No security check required: information retrieval only.  If
377      * new functions are added here, a check might be required.
378      */
379     switch (cmd) {
380     case ACPIIO_BATT_GET_UNITS:
381 	*(int *)addr = acpi_battery_get_units();
382 	error = 0;
383 	break;
384     case ACPIIO_BATT_GET_BATTINFO:
385 	if (dev != NULL || unit == ACPI_BATTERY_ALL_UNITS) {
386 	    bzero(&ioctl_arg->battinfo, sizeof(ioctl_arg->battinfo));
387 	    error = acpi_battery_get_battinfo(dev, &ioctl_arg->battinfo);
388 	}
389 	break;
390     case ACPIIO_BATT_GET_BIF:
391 	if (dev != NULL) {
392 	    bzero(&ioctl_arg->bif, sizeof(ioctl_arg->bif));
393 	    error = ACPI_BATT_GET_INFO(dev, &ioctl_arg->bif);
394 
395 	    /*
396 	     * Remove invalid characters.  Perhaps this should be done
397 	     * within a convenience function so all callers get the
398 	     * benefit.
399 	     */
400 	    acpi_battery_clean_str(ioctl_arg->bif.model,
401 		sizeof(ioctl_arg->bif.model));
402 	    acpi_battery_clean_str(ioctl_arg->bif.serial,
403 		sizeof(ioctl_arg->bif.serial));
404 	    acpi_battery_clean_str(ioctl_arg->bif.type,
405 		sizeof(ioctl_arg->bif.type));
406 	    acpi_battery_clean_str(ioctl_arg->bif.oeminfo,
407 		sizeof(ioctl_arg->bif.oeminfo));
408 	}
409 	break;
410     case ACPIIO_BATT_GET_BST:
411 	if (dev != NULL) {
412 	    bzero(&ioctl_arg->bst, sizeof(ioctl_arg->bst));
413 	    error = ACPI_BATT_GET_STATUS(dev, &ioctl_arg->bst);
414 	}
415 	break;
416     default:
417 	error = EINVAL;
418     }
419 
420     return (error);
421 }
422 
423 static int
424 acpi_battery_sysctl(SYSCTL_HANDLER_ARGS)
425 {
426     int val, error;
427 
428     acpi_battery_get_battinfo(NULL, &acpi_battery_battinfo);
429     val = *(u_int *)oidp->oid_arg1;
430     error = sysctl_handle_int(oidp, &val, 0, req);
431     return (error);
432 }
433 
434 static int
435 acpi_battery_units_sysctl(SYSCTL_HANDLER_ARGS)
436 {
437     int count, error;
438 
439     count = acpi_battery_get_units();
440     error = sysctl_handle_int(oidp, &count, 0, req);
441     return (error);
442 }
443 
444 static int
445 acpi_battery_init(void)
446 {
447     struct acpi_softc	*sc;
448     device_t		 dev;
449     int	 		 error;
450 
451     ACPI_SERIAL_ASSERT(battery);
452 
453     error = ENXIO;
454     dev = devclass_get_device(devclass_find("acpi"), 0);
455     if (dev == NULL)
456 	goto out;
457     sc = device_get_softc(dev);
458 
459     error = acpi_register_ioctl(ACPIIO_BATT_GET_UNITS, acpi_battery_ioctl,
460 	NULL);
461     if (error != 0)
462 	goto out;
463     error = acpi_register_ioctl(ACPIIO_BATT_GET_BATTINFO, acpi_battery_ioctl,
464 	NULL);
465     if (error != 0)
466 	goto out;
467     error = acpi_register_ioctl(ACPIIO_BATT_GET_BIF, acpi_battery_ioctl, NULL);
468     if (error != 0)
469 	goto out;
470     error = acpi_register_ioctl(ACPIIO_BATT_GET_BST, acpi_battery_ioctl, NULL);
471     if (error != 0)
472 	goto out;
473 
474     sysctl_ctx_init(&acpi_battery_sysctl_ctx);
475     acpi_battery_sysctl_tree = SYSCTL_ADD_NODE(&acpi_battery_sysctl_ctx,
476 	SYSCTL_CHILDREN(sc->acpi_sysctl_tree), OID_AUTO, "battery", CTLFLAG_RD,
477 	0, "battery status and info");
478     SYSCTL_ADD_PROC(&acpi_battery_sysctl_ctx,
479 	SYSCTL_CHILDREN(acpi_battery_sysctl_tree),
480 	OID_AUTO, "life", CTLTYPE_INT | CTLFLAG_RD,
481 	&acpi_battery_battinfo.cap, 0, acpi_battery_sysctl, "I",
482 	"percent capacity remaining");
483     SYSCTL_ADD_PROC(&acpi_battery_sysctl_ctx,
484 	SYSCTL_CHILDREN(acpi_battery_sysctl_tree),
485 	OID_AUTO, "time", CTLTYPE_INT | CTLFLAG_RD,
486 	&acpi_battery_battinfo.min, 0, acpi_battery_sysctl, "I",
487 	"remaining time in minutes");
488     SYSCTL_ADD_PROC(&acpi_battery_sysctl_ctx,
489 	SYSCTL_CHILDREN(acpi_battery_sysctl_tree),
490 	OID_AUTO, "state", CTLTYPE_INT | CTLFLAG_RD,
491 	&acpi_battery_battinfo.state, 0, acpi_battery_sysctl, "I",
492 	"current status flags");
493     SYSCTL_ADD_PROC(&acpi_battery_sysctl_ctx,
494 	SYSCTL_CHILDREN(acpi_battery_sysctl_tree),
495 	OID_AUTO, "units", CTLTYPE_INT | CTLFLAG_RD,
496 	NULL, 0, acpi_battery_units_sysctl, "I", "number of batteries");
497     SYSCTL_ADD_INT(&acpi_battery_sysctl_ctx,
498 	SYSCTL_CHILDREN(acpi_battery_sysctl_tree),
499 	OID_AUTO, "info_expire", CTLFLAG_RW,
500 	&acpi_battery_info_expire, 0,
501 	"time in seconds until info is refreshed");
502 
503     acpi_batteries_initted = TRUE;
504 
505 out:
506     if (error != 0) {
507 	acpi_deregister_ioctl(ACPIIO_BATT_GET_UNITS, acpi_battery_ioctl);
508 	acpi_deregister_ioctl(ACPIIO_BATT_GET_BATTINFO, acpi_battery_ioctl);
509 	acpi_deregister_ioctl(ACPIIO_BATT_GET_BIF, acpi_battery_ioctl);
510 	acpi_deregister_ioctl(ACPIIO_BATT_GET_BST, acpi_battery_ioctl);
511     }
512     return (error);
513 }
514