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
27 * $FreeBSD: src/sys/dev/acpica/acpi_battery.c,v 1.30 2009/08/20 19:17:53 jhb
31 #include <sys/param.h>
32 #include <sys/kernel.h>
33 #include <sys/malloc.h>
35 #include <sys/ioccom.h>
36 #include <sys/sysctl.h>
40 #include <dev/acpica5/acpivar.h>
41 #include <dev/acpica5/acpiio.h>
43 /* Default seconds before re-sampling the battery state. */
44 #define ACPI_BATTERY_INFO_EXPIRE 5
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;
52 ACPI_SERIAL_DECL(battery, "ACPI generic battery");
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);
63 acpi_battery_register(device_t dev)
68 ACPI_SERIAL_INIT(battery);
69 ACPI_SERIAL_BEGIN(battery);
70 if (!acpi_batteries_initted)
71 error = acpi_battery_init();
72 ACPI_SERIAL_END(battery);
77 acpi_battery_remove(device_t dev)
84 acpi_battery_get_units(void)
88 batt_dc = devclass_find("battery");
91 return (devclass_get_count(batt_dc));
95 acpi_battery_get_info_expire(void)
98 return (acpi_battery_info_expire);
101 /* Check _BST results for validity. */
103 acpi_battery_bst_valid(struct acpi_bst *bst)
105 return (bst->state < ACPI_BATT_STAT_MAX && bst->cap != ACPI_BATT_UNKNOWN &&
106 bst->volt != ACPI_BATT_UNKNOWN);
109 /* Check _BIF results for validity. */
111 acpi_battery_bif_valid(struct acpi_bif *bif)
113 return (bif->lfcap != 0);
116 /* Get info about one or all batteries. */
118 acpi_battery_get_battinfo(device_t dev, struct acpi_battinfo *battinfo)
120 int batt_stat, devcount, dev_idx, error, i;
121 int total_cap, total_min, valid_rate, valid_units;
124 struct acpi_bst *bst;
125 struct acpi_bif *bif;
126 struct acpi_battinfo *bi;
129 * Get the battery devclass and max unit for battery devices. If there
130 * are none or error, return immediately.
132 batt_dc = devclass_find("battery");
135 devcount = devclass_get_maxunit(batt_dc);
140 * Allocate storage for all _BST data, their derived battinfo data,
141 * and the current battery's _BIF data.
143 bst = kmalloc(devcount * sizeof(*bst), M_TEMP, M_WAITOK | M_ZERO);
144 bi = kmalloc(devcount * sizeof(*bi), M_TEMP, M_WAITOK | M_ZERO);
145 bif = kmalloc(sizeof(*bif), M_TEMP, M_WAITOK | M_ZERO);
148 * Pass 1: for each battery that is present and valid, get its status,
149 * calculate percent capacity remaining, and sum all the current
153 batt_stat = valid_rate = valid_units = 0;
154 for (i = 0; i < devcount; i++) {
155 /* Default info for every battery is "not present". */
156 acpi_reset_battinfo(&bi[i]);
159 * Find the device. Since devcount is in terms of max units, this
160 * may be a sparse array so skip devices that aren't present.
162 batt_dev = devclass_get_device(batt_dc, i);
163 if (batt_dev == NULL)
166 /* If examining a specific battery and this is it, record its index. */
167 if (dev != NULL && dev == batt_dev)
171 * Be sure we can get various info from the battery. Note that
172 * acpi_BatteryIsPresent() is not enough because smart batteries only
173 * return that the device is present.
175 if (!acpi_BatteryIsPresent(batt_dev) ||
176 ACPI_BATT_GET_STATUS(batt_dev, &bst[i]) != 0 ||
177 ACPI_BATT_GET_INFO(batt_dev, bif) != 0)
180 /* If a battery is not installed, we sometimes get strange values. */
181 if (!acpi_battery_bst_valid(&bst[i]) ||
182 !acpi_battery_bif_valid(bif))
186 * Record current state. If both charging and discharging are set,
187 * ignore the charging flag.
190 if ((bst[i].state & ACPI_BATT_STAT_DISCHARG) != 0)
191 bst[i].state &= ~ACPI_BATT_STAT_CHARGING;
192 batt_stat |= bst[i].state;
193 bi[i].state = bst[i].state;
196 * If the battery info is in terms of mA, convert to mW by
197 * multiplying by the design voltage. If the design voltage
198 * is 0 (due to some error reading the battery), skip this
201 if (bif->units == ACPI_BIF_UNITS_MA && bif->dvol != 0 && dev == NULL) {
202 bst[i].rate = (bst[i].rate * bif->dvol) / 1000;
203 bst[i].cap = (bst[i].cap * bif->dvol) / 1000;
204 bif->lfcap = (bif->lfcap * bif->dvol) / 1000;
207 /* Calculate percent capacity remaining. */
208 bi[i].cap = (100 * bst[i].cap) / bif->lfcap;
211 * Some laptops report the "design-capacity" instead of the
212 * "real-capacity" when the battery is fully charged. That breaks
213 * the above arithmetic as it needs to be 100% maximum.
219 * On systems with more than one battery, they may get used
220 * sequentially, thus bst.rate may only signify the one currently
221 * in use. For the remaining batteries, bst.rate will be zero,
222 * which makes it impossible to calculate the total remaining time.
223 * Therefore, we sum the bst.rate for batteries in the discharging
224 * state and use the sum to calculate the total remaining time.
226 if (bst[i].rate != ACPI_BATT_UNKNOWN &&
227 (bst[i].state & ACPI_BATT_STAT_DISCHARG) != 0)
228 valid_rate += bst[i].rate;
231 /* If the caller asked for a device but we didn't find it, error. */
232 if (dev != NULL && dev_idx == -1) {
237 /* Pass 2: calculate capacity and remaining time for all batteries. */
238 total_cap = total_min = 0;
239 for (i = 0; i < devcount; i++) {
241 * If any batteries are discharging, use the sum of the bst.rate
242 * values. Otherwise, we are on AC power, and there is infinite
243 * time remaining for this battery until we go offline.
246 bi[i].min = (60 * bst[i].cap) / valid_rate;
249 total_min += bi[i].min;
251 /* If this battery is not present, don't use its capacity. */
253 total_cap += bi[i].cap;
257 * Return total battery percent and time remaining. If there are
258 * no valid batteries, report values as unknown.
260 if (valid_units > 0) {
262 battinfo->cap = total_cap / valid_units;
263 battinfo->min = total_min;
264 battinfo->state = batt_stat;
265 battinfo->rate = valid_rate;
267 battinfo->cap = bi[dev_idx].cap;
268 battinfo->min = bi[dev_idx].min;
269 battinfo->state = bi[dev_idx].state;
270 battinfo->rate = bst[dev_idx].rate;
274 * If the queried battery has no discharge rate or is charging,
275 * report that we don't know the remaining time.
277 if (valid_rate == 0 || (battinfo->state & ACPI_BATT_STAT_CHARGING))
280 acpi_reset_battinfo(battinfo);
295 acpi_reset_battinfo(struct acpi_battinfo *info)
299 info->state = ACPI_BATT_STAT_NOT_PRESENT;
303 /* Make string printable, removing invalid chars. */
305 acpi_battery_clean_str(char *str, int len)
309 for (i = 0; i < len && *str != '\0'; i++, str++) {
314 /* NUL-terminate the string if we reached the end. */
320 * The battery interface deals with devices and methods but userland
321 * expects a logical unit number. Convert a logical unit to a device_t.
324 acpi_battery_find_dev(u_int logical_unit)
326 int found_unit, i, maxunit;
332 batt_dc = devclass_find("battery");
333 maxunit = devclass_get_maxunit(batt_dc);
334 for (i = 0; i < maxunit; i++) {
335 dev = devclass_get_device(batt_dc, i);
338 if (logical_unit == found_unit)
348 acpi_battery_ioctl(u_long cmd, caddr_t addr, void *arg)
350 union acpi_battery_ioctl_arg *ioctl_arg;
354 /* For commands that use the ioctl_arg struct, validate it first. */
359 if (IOCPARM_LEN(cmd) == sizeof(*ioctl_arg)) {
360 ioctl_arg = (union acpi_battery_ioctl_arg *)addr;
361 unit = ioctl_arg->unit;
362 if (unit != ACPI_BATTERY_ALL_UNITS)
363 dev = acpi_battery_find_dev(unit);
367 * No security check required: information retrieval only. If
368 * new functions are added here, a check might be required.
371 case ACPIIO_BATT_GET_UNITS:
372 *(int *)addr = acpi_battery_get_units();
375 case ACPIIO_BATT_GET_BATTINFO:
376 if (dev != NULL || unit == ACPI_BATTERY_ALL_UNITS) {
377 bzero(&ioctl_arg->battinfo, sizeof(ioctl_arg->battinfo));
378 error = acpi_battery_get_battinfo(dev, &ioctl_arg->battinfo);
381 case ACPIIO_BATT_GET_BIF:
383 bzero(&ioctl_arg->bif, sizeof(ioctl_arg->bif));
384 error = ACPI_BATT_GET_INFO(dev, &ioctl_arg->bif);
387 * Remove invalid characters. Perhaps this should be done
388 * within a convenience function so all callers get the
391 acpi_battery_clean_str(ioctl_arg->bif.model,
392 sizeof(ioctl_arg->bif.model));
393 acpi_battery_clean_str(ioctl_arg->bif.serial,
394 sizeof(ioctl_arg->bif.serial));
395 acpi_battery_clean_str(ioctl_arg->bif.type,
396 sizeof(ioctl_arg->bif.type));
397 acpi_battery_clean_str(ioctl_arg->bif.oeminfo,
398 sizeof(ioctl_arg->bif.oeminfo));
401 case ACPIIO_BATT_GET_BST:
403 bzero(&ioctl_arg->bst, sizeof(ioctl_arg->bst));
404 error = ACPI_BATT_GET_STATUS(dev, &ioctl_arg->bst);
415 acpi_battery_sysctl(SYSCTL_HANDLER_ARGS)
419 acpi_battery_get_battinfo(NULL, &acpi_battery_battinfo);
420 val = *(u_int *)oidp->oid_arg1;
421 error = sysctl_handle_int(oidp, &val, 0, req);
426 acpi_battery_units_sysctl(SYSCTL_HANDLER_ARGS)
430 count = acpi_battery_get_units();
431 error = sysctl_handle_int(oidp, &count, 0, req);
436 acpi_battery_init(void)
438 struct acpi_softc *sc;
442 ACPI_SERIAL_ASSERT(battery);
445 dev = devclass_get_device(devclass_find("acpi"), 0);
448 sc = device_get_softc(dev);
450 error = acpi_register_ioctl(ACPIIO_BATT_GET_UNITS, acpi_battery_ioctl,
454 error = acpi_register_ioctl(ACPIIO_BATT_GET_BATTINFO, acpi_battery_ioctl,
458 error = acpi_register_ioctl(ACPIIO_BATT_GET_BIF, acpi_battery_ioctl, NULL);
461 error = acpi_register_ioctl(ACPIIO_BATT_GET_BST, acpi_battery_ioctl, NULL);
465 sysctl_ctx_init(&acpi_battery_sysctl_ctx);
466 acpi_battery_sysctl_tree = SYSCTL_ADD_NODE(&acpi_battery_sysctl_ctx,
467 SYSCTL_CHILDREN(sc->acpi_sysctl_tree), OID_AUTO, "battery", CTLFLAG_RD,
468 0, "battery status and info");
469 SYSCTL_ADD_PROC(&acpi_battery_sysctl_ctx,
470 SYSCTL_CHILDREN(acpi_battery_sysctl_tree),
471 OID_AUTO, "life", CTLTYPE_INT | CTLFLAG_RD,
472 &acpi_battery_battinfo.cap, 0, acpi_battery_sysctl, "I",
473 "percent capacity remaining");
474 SYSCTL_ADD_PROC(&acpi_battery_sysctl_ctx,
475 SYSCTL_CHILDREN(acpi_battery_sysctl_tree),
476 OID_AUTO, "time", CTLTYPE_INT | CTLFLAG_RD,
477 &acpi_battery_battinfo.min, 0, acpi_battery_sysctl, "I",
478 "remaining time in minutes");
479 SYSCTL_ADD_PROC(&acpi_battery_sysctl_ctx,
480 SYSCTL_CHILDREN(acpi_battery_sysctl_tree),
481 OID_AUTO, "state", CTLTYPE_INT | CTLFLAG_RD,
482 &acpi_battery_battinfo.state, 0, acpi_battery_sysctl, "I",
483 "current status flags");
484 SYSCTL_ADD_PROC(&acpi_battery_sysctl_ctx,
485 SYSCTL_CHILDREN(acpi_battery_sysctl_tree),
486 OID_AUTO, "units", CTLTYPE_INT | CTLFLAG_RD,
487 NULL, 0, acpi_battery_units_sysctl, "I", "number of batteries");
488 SYSCTL_ADD_INT(&acpi_battery_sysctl_ctx,
489 SYSCTL_CHILDREN(acpi_battery_sysctl_tree),
490 OID_AUTO, "info_expire", CTLFLAG_RW,
491 &acpi_battery_info_expire, 0,
492 "time in seconds until info is refreshed");
494 acpi_batteries_initted = TRUE;
498 acpi_deregister_ioctl(ACPIIO_BATT_GET_UNITS, acpi_battery_ioctl);
499 acpi_deregister_ioctl(ACPIIO_BATT_GET_BATTINFO, acpi_battery_ioctl);
500 acpi_deregister_ioctl(ACPIIO_BATT_GET_BIF, acpi_battery_ioctl);
501 acpi_deregister_ioctl(ACPIIO_BATT_GET_BST, acpi_battery_ioctl);