xref: /freebsd/sys/dev/acpica/acpi_battery.c (revision f0a75d274af375d15b97b830966b99a02b7db911)
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/acpi.h>
40 #include <dev/acpica/acpivar.h>
41 #include <dev/acpica/acpiio.h>
42 
43 /* Default seconds before re-sampling the battery state. */
44 #define	ACPI_BATTERY_INFO_EXPIRE	5
45 
46 static int	acpi_batteries_initted;
47 static int	acpi_battery_info_expire = ACPI_BATTERY_INFO_EXPIRE;
48 static struct	acpi_battinfo	acpi_battery_battinfo;
49 static struct	sysctl_ctx_list	acpi_battery_sysctl_ctx;
50 static struct	sysctl_oid	*acpi_battery_sysctl_tree;
51 
52 ACPI_SERIAL_DECL(battery, "ACPI generic battery");
53 
54 static void acpi_reset_battinfo(struct acpi_battinfo *info);
55 static void acpi_battery_clean_str(char *str, int len);
56 static device_t acpi_battery_find_dev(u_int logical_unit);
57 static int acpi_battery_ioctl(u_long cmd, caddr_t addr, void *arg);
58 static int acpi_battery_sysctl(SYSCTL_HANDLER_ARGS);
59 static int acpi_battery_units_sysctl(SYSCTL_HANDLER_ARGS);
60 static int acpi_battery_init(void);
61 
62 int
63 acpi_battery_register(device_t dev)
64 {
65     int error;
66 
67     error = 0;
68     ACPI_SERIAL_BEGIN(battery);
69     if (!acpi_batteries_initted)
70 	error = acpi_battery_init();
71     ACPI_SERIAL_END(battery);
72     return (error);
73 }
74 
75 int
76 acpi_battery_remove(device_t dev)
77 {
78 
79     return (0);
80 }
81 
82 int
83 acpi_battery_get_units(void)
84 {
85     devclass_t batt_dc;
86 
87     batt_dc = devclass_find("battery");
88     if (batt_dc == NULL)
89 	return (0);
90     return (devclass_get_count(batt_dc));
91 }
92 
93 int
94 acpi_battery_get_info_expire(void)
95 {
96 
97     return (acpi_battery_info_expire);
98 }
99 
100 /* Check _BST results for validity. */
101 int
102 acpi_battery_bst_valid(struct acpi_bst *bst)
103 {
104     return (bst->state < ACPI_BATT_STAT_MAX && bst->cap != ACPI_BATT_UNKNOWN &&
105 	bst->volt != ACPI_BATT_UNKNOWN);
106 }
107 
108 /* Check _BIF results for validity. */
109 int
110 acpi_battery_bif_valid(struct acpi_bif *bif)
111 {
112     return (bif->lfcap != 0);
113 }
114 
115 /* Get info about one or all batteries. */
116 int
117 acpi_battery_get_battinfo(device_t dev, struct acpi_battinfo *battinfo)
118 {
119     int	batt_stat, devcount, dev_idx, error, i;
120     int total_cap, total_min, valid_rate, valid_units;
121     devclass_t batt_dc;
122     device_t batt_dev;
123     struct acpi_bst *bst;
124     struct acpi_bif *bif;
125     struct acpi_battinfo *bi;
126 
127     /*
128      * Get the battery devclass and max unit for battery devices.  If there
129      * are none or error, return immediately.
130      */
131     batt_dc = devclass_find("battery");
132     if (batt_dc == NULL)
133 	return (ENXIO);
134     devcount = devclass_get_maxunit(batt_dc);
135     if (devcount == 0)
136 	return (ENXIO);
137 
138     /*
139      * Allocate storage for all _BST data, their derived battinfo data,
140      * and the current battery's _BIF data.
141      */
142     bst = malloc(devcount * sizeof(*bst), M_TEMP, M_WAITOK | M_ZERO);
143     bi = malloc(devcount * sizeof(*bi), M_TEMP, M_WAITOK | M_ZERO);
144     bif = malloc(sizeof(*bif), M_TEMP, M_WAITOK | M_ZERO);
145 
146     /*
147      * Pass 1:  for each battery that is present and valid, get its status,
148      * calculate percent capacity remaining, and sum all the current
149      * discharge rates.
150      */
151     dev_idx = -1;
152     batt_stat = valid_rate = valid_units = 0;
153     for (i = 0; i < devcount; i++) {
154 	/* Default info for every battery is "not present". */
155 	acpi_reset_battinfo(&bi[i]);
156 
157 	/*
158 	 * Find the device.  Since devcount is in terms of max units, this
159 	 * may be a sparse array so skip devices that aren't present.
160 	 */
161 	batt_dev = devclass_get_device(batt_dc, i);
162 	if (batt_dev == NULL)
163 	    continue;
164 
165 	/* If examining a specific battery and this is it, record its index. */
166 	if (dev != NULL && dev == batt_dev)
167 	    dev_idx = i;
168 
169 	/*
170 	 * Be sure we can get various info from the battery.  Note that we
171 	 * can't check acpi_BatteryIsPresent() because smart batteries only
172 	 * return that the device is present.
173 	 */
174 	if (ACPI_BATT_GET_STATUS(batt_dev, &bst[i]) != 0 ||
175 	    ACPI_BATT_GET_INFO(batt_dev, bif) != 0)
176 	    continue;
177 
178 	/* If a battery is not installed, we sometimes get strange values. */
179 	if (!acpi_battery_bst_valid(&bst[i]) ||
180 	    !acpi_battery_bif_valid(bif))
181 	    continue;
182 
183 	/*
184 	 * Record current state.  If both charging and discharging are set,
185 	 * ignore the charging flag.
186 	 */
187 	valid_units++;
188 	if ((bst[i].state & ACPI_BATT_STAT_DISCHARG) != 0)
189 	    bst[i].state &= ~ACPI_BATT_STAT_CHARGING;
190 	batt_stat |= bst[i].state;
191 	bi[i].state = bst[i].state;
192 
193 	/*
194 	 * If the battery info is in terms of mA, convert to mW by
195 	 * multiplying by the design voltage.
196 	 */
197 	if (bif->units == ACPI_BIF_UNITS_MA) {
198 	    bst[i].rate = (bst[i].rate * bif->dvol) / 1000;
199 	    bst[i].cap = (bst[i].cap * bif->dvol) / 1000;
200 	    bif->lfcap = (bif->lfcap * bif->dvol) / 1000;
201 	}
202 
203 	/* Calculate percent capacity remaining. */
204 	bi[i].cap = (100 * bst[i].cap) / bif->lfcap;
205 
206 	/*
207 	 * Some laptops report the "design-capacity" instead of the
208 	 * "real-capacity" when the battery is fully charged.  That breaks
209 	 * the above arithmetic as it needs to be 100% maximum.
210 	 */
211 	if (bi[i].cap > 100)
212 	    bi[i].cap = 100;
213 
214 	/*
215 	 * On systems with more than one battery, they may get used
216 	 * sequentially, thus bst.rate may only signify the one currently
217 	 * in use.  For the remaining batteries, bst.rate will be zero,
218 	 * which makes it impossible to calculate the total remaining time.
219 	 * Therefore, we sum the bst.rate for batteries in the discharging
220 	 * state and use the sum to calculate the total remaining time.
221 	 */
222 	if (bst[i].rate != ACPI_BATT_UNKNOWN &&
223 	    (bst[i].state & ACPI_BATT_STAT_DISCHARG) != 0)
224 	    valid_rate += bst[i].rate;
225     }
226 
227     /* If the caller asked for a device but we didn't find it, error. */
228     if (dev != NULL && dev_idx == -1) {
229 	error = ENXIO;
230 	goto out;
231     }
232 
233     /* Pass 2:  calculate capacity and remaining time for all batteries. */
234     total_cap = total_min = 0;
235     for (i = 0; i < devcount; i++) {
236 	/*
237 	 * If any batteries are discharging, use the sum of the bst.rate
238 	 * values.  Otherwise, we are on AC power, and there is infinite
239 	 * time remaining for this battery until we go offline.
240 	 */
241 	if (valid_rate > 0)
242 	    bi[i].min = (60 * bst[i].cap) / valid_rate;
243 	else
244 	    bi[i].min = 0;
245 	total_min += bi[i].min;
246 
247 	/* If this battery is not present, don't use its capacity. */
248 	if (bi[i].cap != -1)
249 	    total_cap += bi[i].cap;
250     }
251 
252     /*
253      * Return total battery percent and time remaining.  If there are
254      * no valid batteries, report values as unknown.
255      */
256     if (valid_units > 0) {
257 	if (dev == NULL) {
258 	    battinfo->cap = total_cap / valid_units;
259 	    battinfo->min = total_min;
260 	    battinfo->state = batt_stat;
261 	    battinfo->rate = valid_rate;
262 	} else {
263 	    battinfo->cap = bi[dev_idx].cap;
264 	    battinfo->min = bi[dev_idx].min;
265 	    battinfo->state = bi[dev_idx].state;
266 	    battinfo->rate = bst[dev_idx].rate;
267 	}
268 
269 	/*
270 	 * If the queried battery has no discharge rate or is charging,
271 	 * report that we don't know the remaining time.
272 	 */
273 	if (valid_rate == 0 || (battinfo->state & ACPI_BATT_STAT_CHARGING))
274 	    battinfo->min = -1;
275     } else
276 	acpi_reset_battinfo(battinfo);
277 
278     error = 0;
279 
280 out:
281     if (bi)
282 	free(bi, M_TEMP);
283     if (bif)
284 	free(bif, M_TEMP);
285     if (bst)
286 	free(bst, M_TEMP);
287     return (error);
288 }
289 
290 static void
291 acpi_reset_battinfo(struct acpi_battinfo *info)
292 {
293     info->cap = -1;
294     info->min = -1;
295     info->state = ACPI_BATT_STAT_NOT_PRESENT;
296     info->rate = -1;
297 }
298 
299 /* Make string printable, removing invalid chars. */
300 static void
301 acpi_battery_clean_str(char *str, int len)
302 {
303     int i;
304 
305     for (i = 0; i < len && *str != '\0'; i++, str++) {
306 	if (!isprint(*str))
307 	    *str = '?';
308     }
309 
310     /* NUL-terminate the string if we reached the end. */
311     if (i == len)
312 	*str = '\0';
313 }
314 
315 /*
316  * The battery interface deals with devices and methods but userland
317  * expects a logical unit number.  Convert a logical unit to a device_t.
318  */
319 static device_t
320 acpi_battery_find_dev(u_int logical_unit)
321 {
322     int found_unit, i, maxunit;
323     device_t dev;
324     devclass_t batt_dc;
325 
326     dev = NULL;
327     found_unit = 0;
328     batt_dc = devclass_find("battery");
329     maxunit = devclass_get_maxunit(batt_dc);
330     for (i = 0; i < maxunit; i++) {
331 	dev = devclass_get_device(batt_dc, i);
332 	if (dev == NULL)
333 	    continue;
334 	if (logical_unit == found_unit)
335 	    break;
336 	found_unit++;
337 	dev = NULL;
338     }
339 
340     return (dev);
341 }
342 
343 static int
344 acpi_battery_ioctl(u_long cmd, caddr_t addr, void *arg)
345 {
346     union acpi_battery_ioctl_arg *ioctl_arg;
347     int error, unit;
348     device_t dev;
349 
350     /* For commands that use the ioctl_arg struct, validate it first. */
351     error = ENXIO;
352     unit = 0;
353     dev = NULL;
354     ioctl_arg = NULL;
355     if (IOCPARM_LEN(cmd) == sizeof(*ioctl_arg)) {
356 	ioctl_arg = (union acpi_battery_ioctl_arg *)addr;
357 	unit = ioctl_arg->unit;
358 	if (unit != ACPI_BATTERY_ALL_UNITS)
359 	    dev = acpi_battery_find_dev(unit);
360     }
361 
362     /*
363      * No security check required: information retrieval only.  If
364      * new functions are added here, a check might be required.
365      */
366     switch (cmd) {
367     case ACPIIO_BATT_GET_UNITS:
368 	*(int *)addr = acpi_battery_get_units();
369 	error = 0;
370 	break;
371     case ACPIIO_BATT_GET_BATTINFO:
372 	if (dev != NULL || unit == ACPI_BATTERY_ALL_UNITS) {
373 	    bzero(&ioctl_arg->battinfo, sizeof(ioctl_arg->battinfo));
374 	    error = acpi_battery_get_battinfo(dev, &ioctl_arg->battinfo);
375 	}
376 	break;
377     case ACPIIO_BATT_GET_BIF:
378 	if (dev != NULL) {
379 	    bzero(&ioctl_arg->bif, sizeof(ioctl_arg->bif));
380 	    error = ACPI_BATT_GET_INFO(dev, &ioctl_arg->bif);
381 
382 	    /*
383 	     * Remove invalid characters.  Perhaps this should be done
384 	     * within a convenience function so all callers get the
385 	     * benefit.
386 	     */
387 	    acpi_battery_clean_str(ioctl_arg->bif.model,
388 		sizeof(ioctl_arg->bif.model));
389 	    acpi_battery_clean_str(ioctl_arg->bif.serial,
390 		sizeof(ioctl_arg->bif.serial));
391 	    acpi_battery_clean_str(ioctl_arg->bif.type,
392 		sizeof(ioctl_arg->bif.type));
393 	    acpi_battery_clean_str(ioctl_arg->bif.oeminfo,
394 		sizeof(ioctl_arg->bif.oeminfo));
395 	}
396 	break;
397     case ACPIIO_BATT_GET_BST:
398 	if (dev != NULL) {
399 	    bzero(&ioctl_arg->bst, sizeof(ioctl_arg->bst));
400 	    error = ACPI_BATT_GET_STATUS(dev, &ioctl_arg->bst);
401 	}
402 	break;
403     default:
404 	error = EINVAL;
405     }
406 
407     return (error);
408 }
409 
410 static int
411 acpi_battery_sysctl(SYSCTL_HANDLER_ARGS)
412 {
413     int val, error;
414 
415     acpi_battery_get_battinfo(NULL, &acpi_battery_battinfo);
416     val = *(u_int *)oidp->oid_arg1;
417     error = sysctl_handle_int(oidp, &val, 0, req);
418     return (error);
419 }
420 
421 static int
422 acpi_battery_units_sysctl(SYSCTL_HANDLER_ARGS)
423 {
424     int count, error;
425 
426     count = acpi_battery_get_units();
427     error = sysctl_handle_int(oidp, &count, 0, req);
428     return (error);
429 }
430 
431 static int
432 acpi_battery_init(void)
433 {
434     struct acpi_softc	*sc;
435     device_t		 dev;
436     int	 		 error;
437 
438     ACPI_SERIAL_ASSERT(battery);
439 
440     error = ENXIO;
441     dev = devclass_get_device(devclass_find("acpi"), 0);
442     if (dev == NULL)
443 	goto out;
444     sc = device_get_softc(dev);
445 
446     error = acpi_register_ioctl(ACPIIO_BATT_GET_UNITS, acpi_battery_ioctl,
447 	NULL);
448     if (error != 0)
449 	goto out;
450     error = acpi_register_ioctl(ACPIIO_BATT_GET_BATTINFO, acpi_battery_ioctl,
451 	NULL);
452     if (error != 0)
453 	goto out;
454     error = acpi_register_ioctl(ACPIIO_BATT_GET_BIF, acpi_battery_ioctl, NULL);
455     if (error != 0)
456 	goto out;
457     error = acpi_register_ioctl(ACPIIO_BATT_GET_BST, acpi_battery_ioctl, NULL);
458     if (error != 0)
459 	goto out;
460 
461     sysctl_ctx_init(&acpi_battery_sysctl_ctx);
462     acpi_battery_sysctl_tree = SYSCTL_ADD_NODE(&acpi_battery_sysctl_ctx,
463 	SYSCTL_CHILDREN(sc->acpi_sysctl_tree), OID_AUTO, "battery", CTLFLAG_RD,
464 	0, "battery status and info");
465     SYSCTL_ADD_PROC(&acpi_battery_sysctl_ctx,
466 	SYSCTL_CHILDREN(acpi_battery_sysctl_tree),
467 	OID_AUTO, "life", CTLTYPE_INT | CTLFLAG_RD,
468 	&acpi_battery_battinfo.cap, 0, acpi_battery_sysctl, "I",
469 	"percent capacity remaining");
470     SYSCTL_ADD_PROC(&acpi_battery_sysctl_ctx,
471 	SYSCTL_CHILDREN(acpi_battery_sysctl_tree),
472 	OID_AUTO, "time", CTLTYPE_INT | CTLFLAG_RD,
473 	&acpi_battery_battinfo.min, 0, acpi_battery_sysctl, "I",
474 	"remaining time in minutes");
475     SYSCTL_ADD_PROC(&acpi_battery_sysctl_ctx,
476 	SYSCTL_CHILDREN(acpi_battery_sysctl_tree),
477 	OID_AUTO, "state", CTLTYPE_INT | CTLFLAG_RD,
478 	&acpi_battery_battinfo.state, 0, acpi_battery_sysctl, "I",
479 	"current status flags");
480     SYSCTL_ADD_PROC(&acpi_battery_sysctl_ctx,
481 	SYSCTL_CHILDREN(acpi_battery_sysctl_tree),
482 	OID_AUTO, "units", CTLTYPE_INT | CTLFLAG_RD,
483 	NULL, 0, acpi_battery_units_sysctl, "I", "number of batteries");
484     SYSCTL_ADD_INT(&acpi_battery_sysctl_ctx,
485 	SYSCTL_CHILDREN(acpi_battery_sysctl_tree),
486 	OID_AUTO, "info_expire", CTLFLAG_RW,
487 	&acpi_battery_info_expire, 0,
488 	"time in seconds until info is refreshed");
489 
490     acpi_batteries_initted = TRUE;
491 
492 out:
493     if (error != 0) {
494 	acpi_deregister_ioctl(ACPIIO_BATT_GET_UNITS, acpi_battery_ioctl);
495 	acpi_deregister_ioctl(ACPIIO_BATT_GET_BATTINFO, acpi_battery_ioctl);
496 	acpi_deregister_ioctl(ACPIIO_BATT_GET_BIF, acpi_battery_ioctl);
497 	acpi_deregister_ioctl(ACPIIO_BATT_GET_BST, acpi_battery_ioctl);
498     }
499     return (error);
500 }
501