2 * Copyright (c) 2005 Nate Lawson
3 * Copyright (c) 2000 Mitsuru IWASAKI <iwasaki@jp.freebsd.org>
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
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.
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
26 * $FreeBSD: src/sys/dev/acpica/acpi_battery.c,v 1.30 2009/08/20 19:17:53 jhb
29 #include <sys/cdefs.h>
32 #include <sys/param.h>
33 #include <sys/kernel.h>
34 #include <sys/malloc.h>
36 #include <sys/ioccom.h>
37 #include <sys/sysctl.h>
41 #include <dev/acpica5/acpivar.h>
42 #include <dev/acpica5/acpiio.h>
44 /* Default seconds before re-sampling the battery state. */
45 #define ACPI_BATTERY_INFO_EXPIRE 5
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;
53 ACPI_SERIAL_DECL(battery, "ACPI generic battery");
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);
64 acpi_battery_register(device_t dev)
69 ACPI_SERIAL_INIT(battery);
70 ACPI_SERIAL_BEGIN(battery);
71 if (!acpi_batteries_initted)
72 error = acpi_battery_init();
73 ACPI_SERIAL_END(battery);
78 acpi_battery_remove(device_t dev)
85 acpi_battery_get_units(void)
89 batt_dc = devclass_find("battery");
92 return (devclass_get_count(batt_dc));
96 acpi_battery_get_info_expire(void)
99 return (acpi_battery_info_expire);
102 /* Check _BST results for validity. */
104 acpi_battery_bst_valid(struct acpi_bst *bst)
106 return (bst->state < ACPI_BATT_STAT_MAX && bst->cap != ACPI_BATT_UNKNOWN &&
107 bst->volt != ACPI_BATT_UNKNOWN);
110 /* Check _BIF results for validity. */
112 acpi_battery_bif_valid(struct acpi_bif *bif)
114 return (bif->lfcap != 0);
117 /* Get info about one or all batteries. */
119 acpi_battery_get_battinfo(device_t dev, struct acpi_battinfo *battinfo)
121 int batt_stat, devcount, dev_idx, error, i;
122 int total_cap, total_min, valid_rate, valid_units;
125 struct acpi_bst *bst;
126 struct acpi_bif *bif;
127 struct acpi_battinfo *bi;
130 * Get the battery devclass and max unit for battery devices. If there
131 * are none or error, return immediately.
133 batt_dc = devclass_find("battery");
136 devcount = devclass_get_maxunit(batt_dc);
141 * Allocate storage for all _BST data, their derived battinfo data,
142 * and the current battery's _BIF data.
144 bst = kmalloc(devcount * sizeof(*bst), M_TEMP, M_WAITOK | M_ZERO);
145 bi = kmalloc(devcount * sizeof(*bi), M_TEMP, M_WAITOK | M_ZERO);
146 bif = kmalloc(sizeof(*bif), M_TEMP, M_WAITOK | M_ZERO);
149 * Pass 1: for each battery that is present and valid, get its status,
150 * calculate percent capacity remaining, and sum all the current
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]);
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.
163 batt_dev = devclass_get_device(batt_dc, i);
164 if (batt_dev == NULL)
167 /* If examining a specific battery and this is it, record its index. */
168 if (dev != NULL && dev == batt_dev)
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.
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)
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))
187 * Record current state. If both charging and discharging are set,
188 * ignore the charging flag.
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;
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
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;
208 /* Calculate percent capacity remaining. */
209 bi[i].cap = (100 * bst[i].cap) / bif->lfcap;
212 * Some laptops report the "design-capacity" instead of the
213 * "real-capacity" when the battery is fully charged. That breaks
214 * the above arithmetic as it needs to be 100% maximum.
220 * On systems with more than one battery, they may get used
221 * sequentially, thus bst.rate may only signify the one currently
222 * in use. For the remaining batteries, bst.rate will be zero,
223 * which makes it impossible to calculate the total remaining time.
224 * Therefore, we sum the bst.rate for batteries in the discharging
225 * state and use the sum to calculate the total remaining time.
227 if (bst[i].rate != ACPI_BATT_UNKNOWN &&
228 (bst[i].state & ACPI_BATT_STAT_DISCHARG) != 0)
229 valid_rate += bst[i].rate;
232 /* If the caller asked for a device but we didn't find it, error. */
233 if (dev != NULL && dev_idx == -1) {
238 /* Pass 2: calculate capacity and remaining time for all batteries. */
239 total_cap = total_min = 0;
240 for (i = 0; i < devcount; i++) {
242 * If any batteries are discharging, use the sum of the bst.rate
243 * values. Otherwise, we are on AC power, and there is infinite
244 * time remaining for this battery until we go offline.
247 bi[i].min = (60 * bst[i].cap) / valid_rate;
250 total_min += bi[i].min;
252 /* If this battery is not present, don't use its capacity. */
254 total_cap += bi[i].cap;
258 * Return total battery percent and time remaining. If there are
259 * no valid batteries, report values as unknown.
261 if (valid_units > 0) {
263 battinfo->cap = total_cap / valid_units;
264 battinfo->min = total_min;
265 battinfo->state = batt_stat;
266 battinfo->rate = valid_rate;
268 battinfo->cap = bi[dev_idx].cap;
269 battinfo->min = bi[dev_idx].min;
270 battinfo->state = bi[dev_idx].state;
271 battinfo->rate = bst[dev_idx].rate;
275 * If the queried battery has no discharge rate or is charging,
276 * report that we don't know the remaining time.
278 if (valid_rate == 0 || (battinfo->state & ACPI_BATT_STAT_CHARGING))
281 acpi_reset_battinfo(battinfo);
296 acpi_reset_battinfo(struct acpi_battinfo *info)
300 info->state = ACPI_BATT_STAT_NOT_PRESENT;
304 /* Make string printable, removing invalid chars. */
306 acpi_battery_clean_str(char *str, int len)
310 for (i = 0; i < len && *str != '\0'; i++, str++) {
315 /* NUL-terminate the string if we reached the end. */
321 * The battery interface deals with devices and methods but userland
322 * expects a logical unit number. Convert a logical unit to a device_t.
325 acpi_battery_find_dev(u_int logical_unit)
327 int found_unit, i, maxunit;
333 batt_dc = devclass_find("battery");
334 maxunit = devclass_get_maxunit(batt_dc);
335 for (i = 0; i < maxunit; i++) {
336 dev = devclass_get_device(batt_dc, i);
339 if (logical_unit == found_unit)
349 acpi_battery_ioctl(u_long cmd, caddr_t addr, void *arg)
351 union acpi_battery_ioctl_arg *ioctl_arg;
355 /* For commands that use the ioctl_arg struct, validate it first. */
360 if (IOCPARM_LEN(cmd) == sizeof(*ioctl_arg)) {
361 ioctl_arg = (union acpi_battery_ioctl_arg *)addr;
362 unit = ioctl_arg->unit;
363 if (unit != ACPI_BATTERY_ALL_UNITS)
364 dev = acpi_battery_find_dev(unit);
368 * No security check required: information retrieval only. If
369 * new functions are added here, a check might be required.
372 case ACPIIO_BATT_GET_UNITS:
373 *(int *)addr = acpi_battery_get_units();
376 case ACPIIO_BATT_GET_BATTINFO:
377 if (dev != NULL || unit == ACPI_BATTERY_ALL_UNITS) {
378 bzero(&ioctl_arg->battinfo, sizeof(ioctl_arg->battinfo));
379 error = acpi_battery_get_battinfo(dev, &ioctl_arg->battinfo);
382 case ACPIIO_BATT_GET_BIF:
384 bzero(&ioctl_arg->bif, sizeof(ioctl_arg->bif));
385 error = ACPI_BATT_GET_INFO(dev, &ioctl_arg->bif);
388 * Remove invalid characters. Perhaps this should be done
389 * within a convenience function so all callers get the
392 acpi_battery_clean_str(ioctl_arg->bif.model,
393 sizeof(ioctl_arg->bif.model));
394 acpi_battery_clean_str(ioctl_arg->bif.serial,
395 sizeof(ioctl_arg->bif.serial));
396 acpi_battery_clean_str(ioctl_arg->bif.type,
397 sizeof(ioctl_arg->bif.type));
398 acpi_battery_clean_str(ioctl_arg->bif.oeminfo,
399 sizeof(ioctl_arg->bif.oeminfo));
402 case ACPIIO_BATT_GET_BST:
404 bzero(&ioctl_arg->bst, sizeof(ioctl_arg->bst));
405 error = ACPI_BATT_GET_STATUS(dev, &ioctl_arg->bst);
416 acpi_battery_sysctl(SYSCTL_HANDLER_ARGS)
420 acpi_battery_get_battinfo(NULL, &acpi_battery_battinfo);
421 val = *(u_int *)oidp->oid_arg1;
422 error = sysctl_handle_int(oidp, &val, 0, req);
427 acpi_battery_units_sysctl(SYSCTL_HANDLER_ARGS)
431 count = acpi_battery_get_units();
432 error = sysctl_handle_int(oidp, &count, 0, req);
437 acpi_battery_init(void)
439 struct acpi_softc *sc;
443 ACPI_SERIAL_ASSERT(battery);
446 dev = devclass_get_device(devclass_find("acpi"), 0);
449 sc = device_get_softc(dev);
451 error = acpi_register_ioctl(ACPIIO_BATT_GET_UNITS, acpi_battery_ioctl,
455 error = acpi_register_ioctl(ACPIIO_BATT_GET_BATTINFO, acpi_battery_ioctl,
459 error = acpi_register_ioctl(ACPIIO_BATT_GET_BIF, acpi_battery_ioctl, NULL);
462 error = acpi_register_ioctl(ACPIIO_BATT_GET_BST, acpi_battery_ioctl, NULL);
466 sysctl_ctx_init(&acpi_battery_sysctl_ctx);
467 acpi_battery_sysctl_tree = SYSCTL_ADD_NODE(&acpi_battery_sysctl_ctx,
468 SYSCTL_CHILDREN(sc->acpi_sysctl_tree), OID_AUTO, "battery", CTLFLAG_RD,
469 0, "battery status and info");
470 SYSCTL_ADD_PROC(&acpi_battery_sysctl_ctx,
471 SYSCTL_CHILDREN(acpi_battery_sysctl_tree),
472 OID_AUTO, "life", CTLTYPE_INT | CTLFLAG_RD,
473 &acpi_battery_battinfo.cap, 0, acpi_battery_sysctl, "I",
474 "percent capacity remaining");
475 SYSCTL_ADD_PROC(&acpi_battery_sysctl_ctx,
476 SYSCTL_CHILDREN(acpi_battery_sysctl_tree),
477 OID_AUTO, "time", CTLTYPE_INT | CTLFLAG_RD,
478 &acpi_battery_battinfo.min, 0, acpi_battery_sysctl, "I",
479 "remaining time in minutes");
480 SYSCTL_ADD_PROC(&acpi_battery_sysctl_ctx,
481 SYSCTL_CHILDREN(acpi_battery_sysctl_tree),
482 OID_AUTO, "state", CTLTYPE_INT | CTLFLAG_RD,
483 &acpi_battery_battinfo.state, 0, acpi_battery_sysctl, "I",
484 "current status flags");
485 SYSCTL_ADD_PROC(&acpi_battery_sysctl_ctx,
486 SYSCTL_CHILDREN(acpi_battery_sysctl_tree),
487 OID_AUTO, "units", CTLTYPE_INT | CTLFLAG_RD,
488 NULL, 0, acpi_battery_units_sysctl, "I", "number of batteries");
489 SYSCTL_ADD_INT(&acpi_battery_sysctl_ctx,
490 SYSCTL_CHILDREN(acpi_battery_sysctl_tree),
491 OID_AUTO, "info_expire", CTLFLAG_RW,
492 &acpi_battery_info_expire, 0,
493 "time in seconds until info is refreshed");
495 acpi_batteries_initted = TRUE;
499 acpi_deregister_ioctl(ACPIIO_BATT_GET_UNITS, acpi_battery_ioctl);
500 acpi_deregister_ioctl(ACPIIO_BATT_GET_BATTINFO, acpi_battery_ioctl);
501 acpi_deregister_ioctl(ACPIIO_BATT_GET_BIF, acpi_battery_ioctl);
502 acpi_deregister_ioctl(ACPIIO_BATT_GET_BST, acpi_battery_ioctl);