/* Get info about one or all batteries. */
int
acpi_battery_get_battinfo(device_t dev, struct acpi_battinfo *battinfo)
{
int batt_stat, devcount, dev_idx, error, i;
int total_cap, total_min, valid_rate, valid_units;
devclass_t batt_dc;
device_t batt_dev;
struct acpi_bst *bst;
struct acpi_bif *bif;
struct acpi_battinfo *bi;
/*
* Get the battery devclass and max unit for battery devices. If there
* are none or error, return immediately.
*/
batt_dc = devclass_find("battery");
if (batt_dc == NULL)
return (ENXIO);
devcount = devclass_get_maxunit(batt_dc);
if (devcount == 0)
return (ENXIO);
/*
* Allocate storage for all _BST data, their derived battinfo data,
* and the current battery's _BIF data.
*/
bst = kmalloc(devcount * sizeof(*bst), M_TEMP, M_WAITOK | M_ZERO);
bi = kmalloc(devcount * sizeof(*bi), M_TEMP, M_WAITOK | M_ZERO);
bif = kmalloc(sizeof(*bif), M_TEMP, M_WAITOK | M_ZERO);
/*
* Pass 1: for each battery that is present and valid, get its status,
* calculate percent capacity remaining, and sum all the current
* discharge rates.
*/
dev_idx = -1;
batt_stat = valid_rate = valid_units = 0;
for (i = 0; i < devcount; i++) {
/* Default info for every battery is "not present". */
acpi_reset_battinfo(&bi[i]);
/*
* Find the device. Since devcount is in terms of max units, this
* may be a sparse array so skip devices that aren't present.
*/
batt_dev = devclass_get_device(batt_dc, i);
if (batt_dev == NULL)
continue;
/* If examining a specific battery and this is it, record its index. */
if (dev != NULL && dev == batt_dev)
dev_idx = i;
/*
* Be sure we can get various info from the battery. Note that
* acpi_BatteryIsPresent() is not enough because smart batteries only
* return that the device is present.
*/
if (!acpi_BatteryIsPresent(batt_dev) ||
ACPI_BATT_GET_STATUS(batt_dev, &bst[i]) != 0 ||
ACPI_BATT_GET_INFO(batt_dev, bif) != 0)
continue;
/* If a battery is not installed, we sometimes get strange values. */
if (!acpi_battery_bst_valid(&bst[i]) ||
!acpi_battery_bif_valid(bif))
continue;
/*
* Record current state. If both charging and discharging are set,
* ignore the charging flag.
*/
valid_units++;
if ((bst[i].state & ACPI_BATT_STAT_DISCHARG) != 0)
bst[i].state &= ~ACPI_BATT_STAT_CHARGING;
batt_stat |= bst[i].state;
bi[i].state = bst[i].state;
/*
* If the battery info is in terms of mA, convert to mW by
* multiplying by the design voltage. If the design voltage
* is 0 (due to some error reading the battery), skip this
* conversion.
*/
if (bif->units == ACPI_BIF_UNITS_MA && bif->dvol != 0 && dev == NULL) {
bst[i].rate = (bst[i].rate * bif->dvol) / 1000;
bst[i].cap = (bst[i].cap * bif->dvol) / 1000;
bif->lfcap = (bif->lfcap * bif->dvol) / 1000;
}
/*
* The calculation above may set bif->lfcap to zero. This was
* seen on a laptop with a broken battery. The result of the
* division was rounded to zero.
*/
if (!acpi_battery_bif_valid(bif))
continue;
/* Calculate percent capacity remaining. */
bi[i].cap = (100 * bst[i].cap) / bif->lfcap;
/*
* Some laptops report the "design-capacity" instead of the
* "real-capacity" when the battery is fully charged. That breaks
* the above arithmetic as it needs to be 100% maximum.
*/
if (bi[i].cap > 100)
bi[i].cap = 100;
/*
* On systems with more than one battery, they may get used
* sequentially, thus bst.rate may only signify the one currently
* in use. For the remaining batteries, bst.rate will be zero,
* which makes it impossible to calculate the total remaining time.
* Therefore, we sum the bst.rate for batteries in the discharging
* state and use the sum to calculate the total remaining time.
*/
if (bst[i].rate != ACPI_BATT_UNKNOWN &&
(bst[i].state & ACPI_BATT_STAT_DISCHARG) != 0)
valid_rate += bst[i].rate;
/*
* Some DSDTs report a negative 16-bit value for the rate and/or
* report 0 as 65536.
*/
if (acpi_quirks & ACPI_Q_BATT_RATE_ABS &&
bif->units == ACPI_BIF_UNITS_MA &&
bst[i].rate != ACPI_BATT_UNKNOWN &&
(int16_t)bst[i].rate < 0)
bst[i].rate = abs((int16_t)bst[i].rate);
}
/* If the caller asked for a device but we didn't find it, error. */
if (dev != NULL && dev_idx == -1) {
error = ENXIO;
goto out;
}
/* Pass 2: calculate capacity and remaining time for all batteries. */
total_cap = total_min = 0;
for (i = 0; i < devcount; i++) {
/*
* If any batteries are discharging, use the sum of the bst.rate
* values. Otherwise, we are on AC power, and there is infinite
* time remaining for this battery until we go offline.
*/
if (valid_rate > 0)
bi[i].min = (60 * bst[i].cap) / valid_rate;
else
bi[i].min = 0;
total_min += bi[i].min;
/* If this battery is not present, don't use its capacity. */
if (bi[i].cap != -1)
total_cap += bi[i].cap;
}
/*
* Return total battery percent and time remaining. If there are
* no valid batteries, report values as unknown.
*/
if (valid_units > 0) {
if (dev == NULL) {
battinfo->cap = total_cap / valid_units;
battinfo->min = total_min;
battinfo->state = batt_stat;
battinfo->rate = valid_rate;
} else {
battinfo->cap = bi[dev_idx].cap;
battinfo->min = bi[dev_idx].min;
battinfo->state = bi[dev_idx].state;
battinfo->rate = bst[dev_idx].rate;
}
/*
* If the queried battery has no discharge rate or is charging,
* report that we don't know the remaining time.
*/
if (valid_rate == 0 || (battinfo->state & ACPI_BATT_STAT_CHARGING))
battinfo->min = -1;
} else
acpi_reset_battinfo(battinfo);
error = 0;
out:
if (bi)
kfree(bi, M_TEMP);
if (bif)
kfree(bif, M_TEMP);
if (bst)
kfree(bst, M_TEMP);
return (error);
}
static int
acpi_battery_ioctl(u_long cmd, caddr_t addr, void *arg)
{
union acpi_battery_ioctl_arg *ioctl_arg;
int error, unit;
device_t dev;
/* For commands that use the ioctl_arg struct, validate it first. */
error = ENXIO;
unit = 0;
dev = NULL;
ioctl_arg = NULL;
if (IOCPARM_LEN(cmd) == sizeof(*ioctl_arg)) {
ioctl_arg = (union acpi_battery_ioctl_arg *)addr;
unit = ioctl_arg->unit;
if (unit != ACPI_BATTERY_ALL_UNITS)
dev = acpi_battery_find_dev(unit);
}
/*
* No security check required: information retrieval only. If
* new functions are added here, a check might be required.
*/
switch (cmd) {
case ACPIIO_BATT_GET_UNITS:
*(int *)addr = acpi_battery_get_units();
error = 0;
break;
case ACPIIO_BATT_GET_BATTINFO:
if (dev != NULL || unit == ACPI_BATTERY_ALL_UNITS) {
bzero(&ioctl_arg->battinfo, sizeof(ioctl_arg->battinfo));
error = acpi_battery_get_battinfo(dev, &ioctl_arg->battinfo);
}
break;
case ACPIIO_BATT_GET_BIF:
if (dev != NULL) {
bzero(&ioctl_arg->bif, sizeof(ioctl_arg->bif));
error = ACPI_BATT_GET_INFO(dev, &ioctl_arg->bif);
/*
* Remove invalid characters. Perhaps this should be done
* within a convenience function so all callers get the
* benefit.
*/
acpi_battery_clean_str(ioctl_arg->bif.model,
sizeof(ioctl_arg->bif.model));
acpi_battery_clean_str(ioctl_arg->bif.serial,
sizeof(ioctl_arg->bif.serial));
acpi_battery_clean_str(ioctl_arg->bif.type,
sizeof(ioctl_arg->bif.type));
acpi_battery_clean_str(ioctl_arg->bif.oeminfo,
sizeof(ioctl_arg->bif.oeminfo));
}
break;
case ACPIIO_BATT_GET_BST:
if (dev != NULL) {
bzero(&ioctl_arg->bst, sizeof(ioctl_arg->bst));
error = ACPI_BATT_GET_STATUS(dev, &ioctl_arg->bst);
}
break;
default:
error = EINVAL;
}
return (error);
}
static int
acpi_battery_ioctl(u_long cmd, caddr_t addr, void *arg)
{
union acpi_battery_ioctl_arg *ioctl_arg;
int error, unit;
device_t dev;
/*
* Giant is acquired to work around a reference counting bug in ACPICA
* versions prior to 20130328. If not for that bug this function could
* be executed concurrently without any problems.
* The bug is in acpi_BatteryIsPresent -> AcpiGetObjectInfo call tree,
* where AcpiUtExecute_HID, AcpiUtExecute_UID, etc are executed without
* protection of any ACPICA lock and may concurrently call
* AcpiUtRemoveReference on a battery object.
*/
mtx_lock(&Giant);
/* For commands that use the ioctl_arg struct, validate it first. */
error = ENXIO;
unit = 0;
dev = NULL;
ioctl_arg = NULL;
if (IOCPARM_LEN(cmd) == sizeof(*ioctl_arg)) {
ioctl_arg = (union acpi_battery_ioctl_arg *)addr;
unit = ioctl_arg->unit;
if (unit != ACPI_BATTERY_ALL_UNITS)
dev = acpi_battery_find_dev(unit);
}
/*
* No security check required: information retrieval only. If
* new functions are added here, a check might be required.
*/
switch (cmd) {
case ACPIIO_BATT_GET_UNITS:
*(int *)addr = acpi_battery_get_units();
error = 0;
break;
case ACPIIO_BATT_GET_BATTINFO:
if (dev != NULL || unit == ACPI_BATTERY_ALL_UNITS) {
bzero(&ioctl_arg->battinfo, sizeof(ioctl_arg->battinfo));
error = acpi_battery_get_battinfo(dev, &ioctl_arg->battinfo);
}
break;
case ACPIIO_BATT_GET_BIF:
if (dev != NULL) {
bzero(&ioctl_arg->bif, sizeof(ioctl_arg->bif));
error = ACPI_BATT_GET_INFO(dev, &ioctl_arg->bif);
/*
* Remove invalid characters. Perhaps this should be done
* within a convenience function so all callers get the
* benefit.
*/
acpi_battery_clean_str(ioctl_arg->bif.model,
sizeof(ioctl_arg->bif.model));
acpi_battery_clean_str(ioctl_arg->bif.serial,
sizeof(ioctl_arg->bif.serial));
acpi_battery_clean_str(ioctl_arg->bif.type,
sizeof(ioctl_arg->bif.type));
acpi_battery_clean_str(ioctl_arg->bif.oeminfo,
sizeof(ioctl_arg->bif.oeminfo));
}
break;
case ACPIIO_BATT_GET_BST:
if (dev != NULL) {
bzero(&ioctl_arg->bst, sizeof(ioctl_arg->bst));
error = ACPI_BATT_GET_STATUS(dev, &ioctl_arg->bst);
}
break;
default:
error = EINVAL;
}
mtx_unlock(&Giant);
return (error);
}
