Dallas 1-Wire bus support. Includes the following drivers:

gpioow(4)	1-Wire bus bit-banging through GPIO pin
onewire(4)	1-Wire bus driver
owid(4)		1-Wire ID family type device
owtemp(4)	1-Wire temperature family type device

Drivers for RS-232 and USB bus masters will follow.

ok deraadt@

21 files changed, 1697 insertions, 7 deletions

diff --git a/share/man/man4/Makefile b/share/man/man4/Makefile
index c3f57154984..84f2f9baacf 100644
--- a/share/man/man4/Makefile
+++ b/share/man/man4/Makefile
@@ -1,4 +1,4 @@
-#	$OpenBSD: Makefile,v 1.344 2006/02/25 23:53:03 reyk Exp $
+#	$OpenBSD: Makefile,v 1.345 2006/03/04 16:27:03 grange Exp $
 
 MAN=	aac.4 ac97.4 acphy.4 acpi.4 acpitimer.4 \
 	adc.4 addcom.4 admcts.4 admlc.4 admtemp.4 \
@@ -14,7 +14,7 @@ MAN=	aac.4 ac97.4 acphy.4 acpi.4 acpitimer.4 \
 	drum.4 eap.4 ec.4 eephy.4 ef.4 eg.4 ehci.4 eisa.4 el.4 em.4 \
 	emu.4 enc.4 ep.4 epic.4 esa.4 eso.4 ess.4 exphy.4 \
 	faith.4 fd.4 fdc.4 fms.4 fpa.4 fxp.4 gdt.4 gentbi.4 gem.4 gif.4 \
-	glenv.4 gpio.4 gpioiic.4 gpr.4 gre.4 gscsio.4 gtp.4 \
+	glenv.4 gpio.4 gpioiic.4 gpioow.4 gpr.4 gre.4 gscsio.4 gtp.4 \
 	hifn.4 hil.4 hilid.4 hilkbd.4 hilms.4 hme.4 hotplug.4 hpet.4 hsq.4 \
 	ichiic.4 ichwdt.4 icmp.4 icmp6.4 icsphy.4 idp.4 ifmedia.4 \
 	iha.4 iic.4 inet.4 inet6.4 inphy.4 iop.4 iophy.4 ioprbs.4 \
@@ -25,7 +25,8 @@ MAN=	aac.4 ac97.4 acphy.4 acpi.4 acpitimer.4 \
 	mii.4 mpt.4 mpu.4 mtd.4 mtdphy.4 multicast.4 mtio.4 ne.4 neo.4 \
 	netintro.4 nfe.4 nge.4 noct.4 nofn.4 nsclpcsio.4 nsgphy.4 \
 	nsphy.4 nsphyter.4 null.4 nviic.4 ohci.4 opl.4 options.4 \
-	oosiop.4 osiop.4 pcagpio.4 pcdisplay.4 pchb.4 pci.4 pcib.4 pcfadc.4 \
+	onewire.4 oosiop.4 osiop.4 owid.4 owtemp.4 \
+	pcagpio.4 pcdisplay.4 pchb.4 pci.4 pcib.4 pcfadc.4 \
 	pcfiic.4 pciide.4 pckbc.4 pckbd.4 pcmcia.4 pcn.4 pcppi.4 pcscp.4 \
 	pf.4 pflog.4 pfsync.4 piixpm.4 pim.4 \
 	pms.4 ppb.4 ppp.4 pppoe.4 pty.4 puc.4 qsphy.4 radio.4 raid.4 ral.4 \
diff --git a/share/man/man4/gpioow.4 b/share/man/man4/gpioow.4
new file mode 100644
index 00000000000..cc496ef11df
--- /dev/null
+++ b/share/man/man4/gpioow.4
@@ -0,0 +1,53 @@
+.\"	$OpenBSD: gpioow.4,v 1.1 2006/03/04 16:27:03 grange Exp $
+.\"
+.\" Copyright (c) 2006 Alexander Yurchenko <grange@openbsd.org>
+.\"
+.\" Permission to use, copy, modify, and distribute this software for any
+.\" purpose with or without fee is hereby granted, provided that the above
+.\" copyright notice and this permission notice appear in all copies.
+.\"
+.\" THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+.\" WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+.\" MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+.\" ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+.\" WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+.\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+.\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+.\"
+.Dd March 4, 2006
+.Dt GPIOOW 4
+.Os
+.Sh NAME
+.Nm gpioow
+.Nd 1-Wire bus bit-banging through GPIO pin
+.Sh SYNOPSIS
+.Cd "gpioow* at gpio? offset 0 mask 0x1"
+.Cd "onewire* at gpioow?"
+.Sh DESCRIPTION
+The
+.Nm
+driver allows bit-banging a 1-Wire bus as a master using one GPIO pin.
+The pin is used as a data signal.
+GPIO pin must be able to drive an output and read an input.
+.Pp
+Pin number is specified in the kernel configuration with the
+.Ar offset
+locator.
+The
+.Ar mask
+locator should always be 0x1.
+.Sh SEE ALSO
+.Xr gpio 4 ,
+.Xr intro 4 ,
+.Xr onewire 4
+.Sh HISTORY
+The
+.Nm
+driver first appeared in
+.Ox 3.9 .
+.Sh AUTHORS
+.An -nosplit
+The
+.Nm
+driver was written by
+.An Alexander Yurchenko Aq grange@openbsd.org .
diff --git a/share/man/man4/onewire.4 b/share/man/man4/onewire.4
new file mode 100644
index 00000000000..6c5b60dc5a0
--- /dev/null
+++ b/share/man/man4/onewire.4
@@ -0,0 +1,68 @@
+.\"	$OpenBSD: onewire.4,v 1.1 2006/03/04 16:27:03 grange Exp $
+.\"
+.\" Copyright (c) 2006 Alexander Yurchenko <grange@openbsd.org>
+.\"
+.\" Permission to use, copy, modify, and distribute this software for any
+.\" purpose with or without fee is hereby granted, provided that the above
+.\" copyright notice and this permission notice appear in all copies.
+.\"
+.\" THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+.\" WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+.\" MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+.\" ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+.\" WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+.\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+.\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+.\"
+.Dd March 4, 2006
+.Dt ONEWIRE 4
+.Os
+.Sh NAME
+.Nm onewire
+.Nd 1-Wire bus
+.Sh SYNOPSIS
+.Cd "onewire* at gpioow?"
+.Pp
+.Cd "option ONEWIREVERBOSE"
+.Sh DESCRIPTION
+1-Wire bus was originally developed by Dallas Semiconductor for connecting
+integrated circuits.
+It is commonly used for connecting devices such as electronic keys, EEPROMs,
+temperature sensors, real-time clocks, security chips, etc.
+.Pp
+The
+.Nm
+driver provides a uniform programming interface layer between
+1-Wire master controllers and various 1-Wire slave devices.
+Each 1-Wire master controller attaches a
+.Nm
+framework; several slave devices can then be attached to the
+.Nm
+bus.
+.Pp
+The driver supports plugging and unplugging slave devices on the fly.
+.Sh SUPPORTED MASTERS
+.Bl -tag -width 10n -offset ind -compact
+.It Xr gpioow 4
+1-Wire bus bit-banging through GPIO pin
+.El
+.Sh SUPPORTED SLAVES
+.Bl -tag -width 10n -offset ind -compact
+.It Xr owid 4
+ID family type device
+.It Xr owtemp 4
+temperature family type device
+.El
+.Sh SEE ALSO
+.Xr intro 4
+.Sh HISTORY
+The
+.Nm
+driver first appeared in
+.Ox 3.9 .
+.Sh AUTHORS
+.An -nosplit
+The
+.Nm
+driver was written by
+.An Alexander Yurchenko Aq grange@openbsd.org .
diff --git a/share/man/man4/owid.4 b/share/man/man4/owid.4
new file mode 100644
index 00000000000..7983a22f011
--- /dev/null
+++ b/share/man/man4/owid.4
@@ -0,0 +1,53 @@
+.\"	$OpenBSD: owid.4,v 1.1 2006/03/04 16:27:03 grange Exp $
+.\"
+.\" Copyright (c) 2006 Alexander Yurchenko <grange@openbsd.org>
+.\"
+.\" Permission to use, copy, modify, and distribute this software for any
+.\" purpose with or without fee is hereby granted, provided that the above
+.\" copyright notice and this permission notice appear in all copies.
+.\"
+.\" THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+.\" WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+.\" MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+.\" ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+.\" WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+.\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+.\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+.\"
+.Dd March 4, 2006
+.Dt OWID 4
+.Os
+.Sh NAME
+.Nm owid
+.Nd 1-Wire ID family type device
+.Sh SYNOPSIS
+.Cd "owid* at onewire?"
+.Sh DESCRIPTION
+The
+.Nm
+driver provides support for the 1-Wire serial number family type device.
+This device can't do anything except reporting its unique serial number.
+The serial number is available through the
+.Xr sysctl 8
+interface.
+.Pp
+The following chips are supported by the driver:
+.Bl -bullet -compact -offset indent
+.It
+Maxim/Dallas DS1990
+.El
+.Sh SEE ALSO
+.Xr intro 4 ,
+.Xr onewire 4 ,
+.Xr sysctl 8
+.Sh HISTORY
+The
+.Nm
+driver first appeared in
+.Ox 3.9 .
+.Sh AUTHORS
+.An -nosplit
+The
+.Nm
+driver was written by
+.An Alexander Yurchenko Aq grange@openbsd.org .
diff --git a/share/man/man4/owtemp.4 b/share/man/man4/owtemp.4
new file mode 100644
index 00000000000..eb550b7cb56
--- /dev/null
+++ b/share/man/man4/owtemp.4
@@ -0,0 +1,53 @@
+.\"	$OpenBSD: owtemp.4,v 1.1 2006/03/04 16:27:03 grange Exp $
+.\"
+.\" Copyright (c) 2006 Alexander Yurchenko <grange@openbsd.org>
+.\"
+.\" Permission to use, copy, modify, and distribute this software for any
+.\" purpose with or without fee is hereby granted, provided that the above
+.\" copyright notice and this permission notice appear in all copies.
+.\"
+.\" THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+.\" WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+.\" MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+.\" ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+.\" WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+.\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+.\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+.\"
+.Dd March 4, 2006
+.Dt OWTEMP 4
+.Os
+.Sh NAME
+.Nm owtemp
+.Nd 1-Wire temperature family type device
+.Sh SYNOPSIS
+.Cd "owtemp* at onewire?"
+.Sh DESCRIPTION
+The
+.Nm
+driver provides support for the 1-Wire temperature sensor.
+The sensor possesses single temperature value that can be accessed
+through the
+.Xr sysctl 8
+interface.
+.Pp
+The following chips are supported by the driver:
+.Bl -bullet -compact -offset indent
+.It
+Maxim/Dallas DS1820, DS1920
+.El
+.Sh SEE ALSO
+.Xr intro 4 ,
+.Xr onewire 4 ,
+.Xr sysctl 8
+.Sh HISTORY
+The
+.Nm
+driver first appeared in
+.Ox 3.9 .
+.Sh AUTHORS
+.An -nosplit
+The
+.Nm
+driver was written by
+.An Alexander Yurchenko Aq grange@openbsd.org .
diff --git a/sys/arch/i386/conf/GENERIC b/sys/arch/i386/conf/GENERIC
index b2f64d78a87..02096997e4c 100644
--- a/sys/arch/i386/conf/GENERIC
+++ b/sys/arch/i386/conf/GENERIC
@@ -1,4 +1,4 @@
-#	$OpenBSD: GENERIC,v 1.473 2006/03/04 15:33:37 grange Exp $
+#	$OpenBSD: GENERIC,v 1.474 2006/03/04 16:27:03 grange Exp $
 #
 # For further information on compiling OpenBSD kernels, see the config(8)
 # man page.
@@ -73,6 +73,7 @@ option		ACPIVERBOSE
 option		PCIVERBOSE
 option		EISAVERBOSE
 option		USBVERBOSE
+option		ONEWIREVERBOSE
 
 pchb*	at pci?			# PCI-Host bridges
 ppb*	at pci?			# PCI-PCI bridges
@@ -639,6 +640,12 @@ scsibus* at ioprbs?
 # GPIO ``pin bus'' drivers
 #gpioiic* at gpio? offset 0 mask 0x3	# I2C bus bit-banging
 #iic*	at gpioiic?
+#gpioow* at gpio? offset 0 mask 0x1	# 1-Wire bus bit-banging
+#onewire* at gpioow?
+
+# 1-Wire devices
+#owid*	at onewire?			# ID
+#owtemp* at onewire?			# Temperature
 
 pseudo-device	pctr		1
 pseudo-device	mtrr		1	# Memory range attributes control
diff --git a/sys/arch/i386/conf/files.i386 b/sys/arch/i386/conf/files.i386
index 8dd8e70e341..d3130003116 100644
--- a/sys/arch/i386/conf/files.i386
+++ b/sys/arch/i386/conf/files.i386
@@ -1,4 +1,4 @@
-#	$OpenBSD: files.i386,v 1.143 2006/02/12 19:55:39 miod Exp $
+#	$OpenBSD: files.i386,v 1.144 2006/03/04 16:27:03 grange Exp $
 #
 # new style config file for i386 architecture
 #
@@ -394,6 +394,11 @@ include "dev/i2c/files.i2c"
 #
 include "dev/gpio/files.gpio"
 
+#
+# Machine-independent 1-Wire drivers
+#
+include "dev/onewire/files.onewire"
+
 include "../../../dev/acpi/files.acpi"
 file	arch/i386/i386/acpi_machdep.c		acpi
 
diff --git a/sys/conf/files b/sys/conf/files
index 1efe82f5165..00c4f96fcf7 100644
--- a/sys/conf/files
+++ b/sys/conf/files
@@ -1,4 +1,4 @@
-#	$OpenBSD: files,v 1.365 2006/02/01 11:03:33 dlg Exp $
+#	$OpenBSD: files,v 1.366 2006/03/04 16:27:02 grange Exp $
 #	$NetBSD: files,v 1.87 1996/05/19 17:17:50 jonathan Exp $
 
 #	@(#)files.newconf	7.5 (Berkeley) 5/10/93
@@ -18,6 +18,7 @@ define	midisyn
 define	radiobus {}
 define	i2cbus {}
 define	gpiobus {}
+define	onewirebus {}
 
 # filesystem firmware loading attribute
 define firmload
@@ -110,6 +111,9 @@ define	atapi {[channel = -1]}
 device	wdc: ata, atapi, wdc_base
 file	dev/ic/wdc.c			wdc_base
 
+# 1-Wire bus bit-banging
+define	onewire_bitbang
+
 # "Chipset" drivers.  These are the bus-independent routines which
 # contain the cfdrivers.  Attachments are provided by files.<bus>
 
diff --git a/sys/dev/gpio/files.gpio b/sys/dev/gpio/files.gpio
index add5a0cbe11..79fd80d3a03 100644
--- a/sys/dev/gpio/files.gpio
+++ b/sys/dev/gpio/files.gpio
@@ -1,4 +1,4 @@
-# $OpenBSD: files.gpio,v 1.5 2006/01/14 13:55:14 grange Exp $
+# $OpenBSD: files.gpio,v 1.6 2006/03/04 16:27:03 grange Exp $
 
 define	gpio {offset, mask}
 
@@ -10,3 +10,8 @@ file	dev/gpio/gpio.c				gpio	needs-flag
 device	gpioiic: i2cbus, i2c_bitbang
 attach	gpioiic at gpio
 file	dev/gpio/gpioiic.c			gpioiic
+
+# 1-Wire bus bit-banging
+device	gpioow: onewirebus, onewire_bitbang
+attach	gpioow at gpio
+file	dev/gpio/gpioow.c			gpioow
diff --git a/sys/dev/gpio/gpioow.c b/sys/dev/gpio/gpioow.c
new file mode 100644
index 00000000000..94364133eef
--- /dev/null
+++ b/sys/dev/gpio/gpioow.c
@@ -0,0 +1,245 @@
+/*	$OpenBSD: gpioow.c,v 1.1 2006/03/04 16:27:03 grange Exp $	*/
+
+/*
+ * Copyright (c) 2006 Alexander Yurchenko <grange@openbsd.org>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+/*
+ * 1-Wire bus bit-banging through GPIO pin.
+ */
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/device.h>
+#include <sys/gpio.h>
+
+#include <dev/gpio/gpiovar.h>
+
+#include <dev/onewire/onewirevar.h>
+
+#define GPIOOW_NPINS		1
+#define GPIOOW_PIN_DATA		0
+
+struct gpioow_softc {
+	struct device		sc_dev;
+
+	void *			sc_gpio;
+	struct gpio_pinmap	sc_map;
+	int			__map[GPIOOW_NPINS];
+
+	struct onewire_bus	sc_ow_bus;
+	struct device *		sc_ow_dev;
+
+	int			sc_data;
+	int			sc_dying;
+};
+
+int	gpioow_match(struct device *, void *, void *);
+void	gpioow_attach(struct device *, struct device *, void *);
+int	gpioow_detach(struct device *, int);
+int	gpioow_activate(struct device *, enum devact);
+
+int	gpioow_ow_reset(void *);
+int	gpioow_ow_bit(void *, int);
+
+void	gpioow_bb_rx(void *);
+void	gpioow_bb_tx(void *);
+int	gpioow_bb_get(void *);
+void	gpioow_bb_set(void *, int);
+
+struct cfattach gpioow_ca = {
+	sizeof(struct gpioow_softc),
+	gpioow_match,
+	gpioow_attach,
+	gpioow_detach,
+	gpioow_activate
+};
+
+struct cfdriver gpioow_cd = {
+	NULL, "gpioow", DV_DULL
+};
+
+static const struct onewire_bbops gpioow_bbops = {
+	gpioow_bb_rx,
+	gpioow_bb_tx,
+	gpioow_bb_get,
+	gpioow_bb_set
+};
+
+int
+gpioow_match(struct device *parent, void *match, void *aux)
+{
+	struct cfdata *cf = match;
+
+	return (strcmp(cf->cf_driver->cd_name, "gpioow") == 0);
+}
+
+void
+gpioow_attach(struct device *parent, struct device *self, void *aux)
+{
+	struct gpioow_softc *sc = (struct gpioow_softc *)self;
+	struct gpio_attach_args *ga = aux;
+	struct onewirebus_attach_args oba;
+	int caps;
+
+	/* Check that we have enough pins */
+	if (gpio_npins(ga->ga_mask) != GPIOOW_NPINS) {
+		printf(": invalid pin mask\n");
+		return;
+	}
+
+	/* Map pins */
+	sc->sc_gpio = ga->ga_gpio;
+	sc->sc_map.pm_map = sc->__map;
+	if (gpio_pin_map(sc->sc_gpio, ga->ga_offset, ga->ga_mask,
+	    &sc->sc_map)) {
+		printf(": can't map pins\n");
+		return;
+	}
+
+	/* Configure data pin */
+	caps = gpio_pin_caps(sc->sc_gpio, &sc->sc_map, GPIOOW_PIN_DATA);
+	if (!(caps & GPIO_PIN_OUTPUT)) {
+		printf(": data pin is unable to drive output\n");
+		goto fail;
+	}
+	if (!(caps & GPIO_PIN_INPUT)) {
+		printf(": data pin is unable to read input\n");
+		goto fail;
+	}
+	printf(": DATA[%d]", sc->sc_map.pm_map[GPIOOW_PIN_DATA]);
+	sc->sc_data = GPIO_PIN_OUTPUT;
+	if (caps & GPIO_PIN_OPENDRAIN) {
+		printf(" open-drain");
+		sc->sc_data |= GPIO_PIN_OPENDRAIN;
+	} else if ((caps & GPIO_PIN_PUSHPULL) && (caps & GPIO_PIN_TRISTATE)) {
+		printf(" push-pull tri-state");
+		sc->sc_data |= GPIO_PIN_PUSHPULL;
+	}
+	if (caps & GPIO_PIN_PULLUP) {
+		printf(" pull-up");
+		sc->sc_data |= GPIO_PIN_PULLUP;
+	}
+	gpio_pin_ctl(sc->sc_gpio, &sc->sc_map, GPIOOW_PIN_DATA, sc->sc_data);
+
+	printf("\n");
+
+	/* Attach 1-Wire bus */
+	sc->sc_ow_bus.bus_cookie = sc;
+	sc->sc_ow_bus.bus_reset = gpioow_ow_reset;
+	sc->sc_ow_bus.bus_bit = gpioow_ow_bit;
+
+	bzero(&oba, sizeof(oba));
+	oba.oba_bus = &sc->sc_ow_bus;
+	sc->sc_ow_dev = config_found(self, &oba, onewirebus_print);
+
+	return;
+
+fail:
+	gpio_pin_unmap(sc->sc_gpio, &sc->sc_map);
+}
+
+int
+gpioow_detach(struct device *self, int flags)
+{
+	struct gpioow_softc *sc = (struct gpioow_softc *)self;
+	int rv = 0;
+
+	if (sc->sc_ow_dev != NULL)
+		rv = config_detach(sc->sc_ow_dev, flags);
+
+	return (rv);
+}
+
+int
+gpioow_activate(struct device *self, enum devact act)
+{
+	struct gpioow_softc *sc = (struct gpioow_softc *)self;
+	int rv = 0;
+
+	switch (act) {
+	case DVACT_ACTIVATE:
+		return (EOPNOTSUPP);
+	case DVACT_DEACTIVATE:
+		sc->sc_dying = 1;
+		if (sc->sc_ow_dev != NULL)
+			rv = config_deactivate(sc->sc_ow_dev);
+		break;
+	}
+
+	return (rv);
+}
+
+int
+gpioow_ow_reset(void *arg)
+{
+	return (onewire_bb_reset(&gpioow_bbops, arg));
+}
+
+int
+gpioow_ow_bit(void *arg, int value)
+{
+	return (onewire_bb_bit(&gpioow_bbops, arg, value));
+}
+
+void
+gpioow_bb_rx(void *arg)
+{
+	struct gpioow_softc *sc = arg;
+	int data = sc->sc_data;
+
+	data &= ~(GPIO_PIN_INPUT | GPIO_PIN_OUTPUT | GPIO_PIN_TRISTATE);
+	data |= GPIO_PIN_INPUT;
+	if (data & GPIO_PIN_PUSHPULL)
+		data |= GPIO_PIN_TRISTATE;
+	if (sc->sc_data != data) {
+		sc->sc_data = data;
+		gpio_pin_ctl(sc->sc_gpio, &sc->sc_map, GPIOOW_PIN_DATA,
+		    sc->sc_data);
+	}
+}
+
+void
+gpioow_bb_tx(void *arg)
+{
+	struct gpioow_softc *sc = arg;
+	int data = sc->sc_data;
+
+	data &= ~(GPIO_PIN_INPUT | GPIO_PIN_OUTPUT | GPIO_PIN_TRISTATE);
+	data |= GPIO_PIN_OUTPUT;
+	if (sc->sc_data != data) {
+		sc->sc_data = data;
+		gpio_pin_ctl(sc->sc_gpio, &sc->sc_map, GPIOOW_PIN_DATA,
+		    sc->sc_data);
+	}
+}
+
+int
+gpioow_bb_get(void *arg)
+{
+	struct gpioow_softc *sc = arg;
+
+	return (gpio_pin_read(sc->sc_gpio, &sc->sc_map, GPIOOW_PIN_DATA) ==
+	    GPIO_PIN_HIGH ? 1 : 0);
+}
+
+void
+gpioow_bb_set(void *arg, int value)
+{
+	struct gpioow_softc *sc = arg;
+
+	gpio_pin_write(sc->sc_gpio, &sc->sc_map, GPIOOW_PIN_DATA,
+	    value ? GPIO_PIN_HIGH : GPIO_PIN_LOW);
+}
diff --git a/sys/dev/onewire/Makefile b/sys/dev/onewire/Makefile
new file mode 100644
index 00000000000..269c4d22368
--- /dev/null
+++ b/sys/dev/onewire/Makefile
@@ -0,0 +1,7 @@
+# $OpenBSD: Makefile,v 1.1 2006/03/04 16:27:03 grange Exp $
+
+AWK?=	awk
+
+onewiredevs.h onewiredevs_data.h: onewiredevs devlist2h.awk
+	/bin/rm -f onewiredevs.h onewiredevs_data.h
+	${AWK} -f devlist2h.awk onewiredevs
diff --git a/sys/dev/onewire/devlist2h.awk b/sys/dev/onewire/devlist2h.awk
new file mode 100644
index 00000000000..fdb8357d9bf
--- /dev/null
+++ b/sys/dev/onewire/devlist2h.awk
@@ -0,0 +1,55 @@
+# $OpenBSD: devlist2h.awk,v 1.1 2006/03/04 16:27:03 grange Exp $
+
+#
+# Copyright (c) 2006 Alexander Yurchenko <grange@openbsd.org>
+#
+# Permission to use, copy, modify, and distribute this software for any
+# purpose with or without fee is hereby granted, provided that the above
+# copyright notice and this permission notice appear in all copies.
+#
+# THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+# WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+# MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+# ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+# WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+# ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+# OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+#
+
+BEGIN {
+	hfile = "onewiredevs.h"
+	dfile = "onewiredevs_data.h"
+}
+
+NR == 1	{
+	VERSION = $0
+	gsub("\\$", "", VERSION)
+
+	printf("/*\t$OpenBSD: devlist2h.awk,v 1.1 2006/03/04 16:27:03 grange Exp $\t*/\n\n" \
+	       "/*\n * THIS FILE AUTOMATICALLY GENERATED.  DO NOT EDIT.\n" \
+	       " *\n * Generated from:\n *\t%s\n */\n\n", VERSION) > hfile
+	printf("/*\t$OpenBSD: devlist2h.awk,v 1.1 2006/03/04 16:27:03 grange Exp $\t*/\n\n" \
+	       "/*\n * THIS FILE AUTOMATICALLY GENERATED.  DO NOT EDIT.\n" \
+	       " *\n * Generated from:\n *\t%s\n */\n\n", VERSION) > dfile
+	printf("static const struct onewire_family " \
+	       "onewire_familytab[] = {\n") > dfile
+}
+
+$1 == "family" {
+	printf("#define ONEWIRE_FAMILY_%s\t%s\n", toupper($2), $3) > hfile
+	printf("\t{ ONEWIRE_FAMILY_%s, \"", toupper($2)) > dfile
+
+	f = 4
+	while (f <= NF) {
+		if (f > 4)
+			printf(" ") > dfile
+		printf("%s", $f) > dfile
+		f++
+	}
+	printf("\" },\n") > dfile
+	next
+}
+
+END {
+	printf("\t{ 0, NULL }\n};\n") > dfile
+}
diff --git a/sys/dev/onewire/files.onewire b/sys/dev/onewire/files.onewire
new file mode 100644
index 00000000000..682dcc4be73
--- /dev/null
+++ b/sys/dev/onewire/files.onewire
@@ -0,0 +1,20 @@
+# $OpenBSD: files.onewire,v 1.1 2006/03/04 16:27:03 grange Exp $
+
+define	onewire {}
+
+device	onewire: onewire
+attach	onewire at onewirebus
+file	dev/onewire/onewire.c		onewire
+file	dev/onewire/onewire_subr.c	onewire
+
+file	dev/onewire/onewire_bitbang.c	onewire_bitbang
+
+# ID family type device
+device	owid
+attach	owid at onewire
+file	dev/onewire/owid.c		owid
+
+# Temperature family type device
+device	owtemp
+attach	owtemp at onewire
+file	dev/onewire/owtemp.c		owtemp
diff --git a/sys/dev/onewire/onewire.c b/sys/dev/onewire/onewire.c
new file mode 100644
index 00000000000..27144f5844e
--- /dev/null
+++ b/sys/dev/onewire/onewire.c
@@ -0,0 +1,452 @@
+/*	$OpenBSD: onewire.c,v 1.1 2006/03/04 16:27:03 grange Exp $	*/
+
+/*
+ * Copyright (c) 2006 Alexander Yurchenko <grange@openbsd.org>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+/*
+ * 1-Wire bus driver.
+ */
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/device.h>
+#include <sys/kernel.h>
+#include <sys/kthread.h>
+#include <sys/lock.h>
+#include <sys/malloc.h>
+#include <sys/proc.h>
+#include <sys/queue.h>
+
+#include <dev/onewire/onewirereg.h>
+#include <dev/onewire/onewirevar.h>
+
+#ifdef ONEWIRE_DEBUG
+#define DPRINTF(x) printf x
+#else
+#define DPRINTF(x)
+#endif
+
+#define ONEWIRE_MAXDEVS		256
+#define ONEWIRE_SCANTIME	3
+
+struct onewire_softc {
+	struct device			sc_dev;
+
+	struct onewire_bus *		sc_bus;
+	struct lock			sc_lock;
+	struct proc *			sc_thread;
+	TAILQ_HEAD(, onewire_device)	sc_devs;
+
+	int				sc_dying;
+};
+
+struct onewire_device {
+	TAILQ_ENTRY(onewire_device)	d_list;
+	struct device *			d_dev;
+	u_int64_t			d_rom;
+	int				d_present;
+};
+
+int	onewire_match(struct device *, void *, void *);
+void	onewire_attach(struct device *, struct device *, void *);
+int	onewire_detach(struct device *, int);
+int	onewire_activate(struct device *, enum devact);
+int	onewire_print(void *, const char *);
+
+void	onewire_thread(void *);
+void	onewire_createthread(void *);
+void	onewire_scan(struct onewire_softc *);
+
+struct cfattach onewire_ca = {
+	sizeof(struct onewire_softc),
+	onewire_match,
+	onewire_attach,
+	onewire_detach,
+	onewire_activate
+};
+
+struct cfdriver onewire_cd = {
+	NULL, "onewire", DV_DULL
+};
+
+int
+onewire_match(struct device *parent, void *match, void *aux)
+{
+	struct cfdata *cf = match;
+
+	return (strcmp(cf->cf_driver->cd_name, "onewire") == 0);
+}
+
+void
+onewire_attach(struct device *parent, struct device *self, void *aux)
+{
+	struct onewire_softc *sc = (struct onewire_softc *)self;
+	struct onewirebus_attach_args *oba = aux;
+
+	sc->sc_bus = oba->oba_bus;
+	lockinit(&sc->sc_lock, PRIBIO, "owlock", 0, 0);
+	TAILQ_INIT(&sc->sc_devs);
+
+	printf("\n");
+
+	kthread_create_deferred(onewire_createthread, sc);
+}
+
+int
+onewire_detach(struct device *self, int flags)
+{
+	struct onewire_softc *sc = (struct onewire_softc *)self;
+	int rv;
+
+	sc->sc_dying = 1;
+	if (sc->sc_thread != NULL) {
+		wakeup(sc->sc_thread);
+		tsleep(&sc->sc_dying, PWAIT, "owdt", 0);
+	}
+
+	onewire_lock(sc, 0);
+	rv = config_detach_children(self, flags);
+	onewire_unlock(sc);
+
+	return (rv);
+}
+
+int
+onewire_activate(struct device *self, enum devact act)
+{
+	struct onewire_softc *sc = (struct onewire_softc *)self;
+
+	switch (act) {
+	case DVACT_ACTIVATE:
+		break;
+	case DVACT_DEACTIVATE:
+		sc->sc_dying = 1;
+		break;
+	}
+
+	return (config_activate_children(self, act));
+}
+
+int
+onewire_print(void *aux, const char *pnp)
+{
+	struct onewire_attach_args *oa = aux;
+	const char *famname;
+
+	if (pnp == NULL)
+		printf(" ");
+
+	famname = onewire_famname(ONEWIRE_ROM_FAMILY_TYPE(oa->oa_rom));
+	if (famname == NULL)
+		printf("family 0x%02x", ONEWIRE_ROM_FAMILY_TYPE(oa->oa_rom));
+	else
+		printf("\"%s\"", famname);
+	printf(" sn %012llx", ONEWIRE_ROM_SN(oa->oa_rom));
+
+	if (pnp != NULL)
+		printf(" at %s", pnp);
+
+	return (UNCONF);
+}
+
+int
+onewirebus_print(void *aux, const char *pnp)
+{
+	if (pnp != NULL)
+		printf("onewire at %s", pnp);
+
+	return (UNCONF);
+}
+
+int
+onewire_lock(void *arg, int flags)
+{
+	struct onewire_softc *sc = arg;
+	int lflags = LK_EXCLUSIVE;
+
+	if (flags & ONEWIRE_NOWAIT)
+		lflags |= LK_NOWAIT;
+
+	return (lockmgr(&sc->sc_lock, lflags, NULL));
+}
+
+void
+onewire_unlock(void *arg)
+{
+	struct onewire_softc *sc = arg;
+
+	lockmgr(&sc->sc_lock, LK_RELEASE, NULL);
+}
+
+int
+onewire_reset(void *arg)
+{
+	struct onewire_softc *sc = arg;
+	struct onewire_bus *bus = sc->sc_bus;
+
+	return (bus->bus_reset(bus->bus_cookie));
+}
+
+int
+onewire_bit(void *arg, int value)
+{
+	struct onewire_softc *sc = arg;
+	struct onewire_bus *bus = sc->sc_bus;
+
+	return (bus->bus_bit(bus->bus_cookie, value));
+}
+
+int
+onewire_read_byte(void *arg)
+{
+	struct onewire_softc *sc = arg;
+	struct onewire_bus *bus = sc->sc_bus;
+	u_int8_t value = 0;
+	int i;
+
+	if (bus->bus_read_byte != NULL)
+		return (bus->bus_read_byte(bus->bus_cookie));
+
+	for (i = 0; i < 8; i++)
+		value |= (bus->bus_bit(bus->bus_cookie, 1) << i);
+
+	return (value);
+}
+
+void
+onewire_write_byte(void *arg, int value)
+{
+	struct onewire_softc *sc = arg;
+	struct onewire_bus *bus = sc->sc_bus;
+	int i;
+
+	if (bus->bus_write_byte != NULL)
+		return (bus->bus_write_byte(bus->bus_cookie, value));
+
+	for (i = 0; i < 8; i++)
+		bus->bus_bit(bus->bus_cookie, (value >> i) & 0x1);
+}
+
+int
+onewire_triplet(void *arg, int dir)
+{
+	struct onewire_softc *sc = arg;
+	struct onewire_bus *bus = sc->sc_bus;
+	int rv;
+
+	if (bus->bus_triplet != NULL)
+		return (bus->bus_triplet(bus->bus_cookie, dir));
+
+	rv = bus->bus_bit(bus->bus_cookie, 1);
+	rv <<= 1;
+	rv |= bus->bus_bit(bus->bus_cookie, 1);
+
+	switch (rv) {
+	case 0x0:
+		bus->bus_bit(bus->bus_cookie, dir);
+		break;
+	case 0x1:
+		bus->bus_bit(bus->bus_cookie, 0);
+		break;
+	default:
+		bus->bus_bit(bus->bus_cookie, 1);
+	}
+
+	return (rv);
+}
+
+void
+onewire_read_block(void *arg, void *buf, int len)
+{
+	u_int8_t *p = buf;
+
+	while (len--)
+		*p++ = onewire_read_byte(arg);
+}
+
+void
+onewire_write_block(void *arg, const void *buf, int len)
+{
+	const u_int8_t *p = buf;
+
+	while (len--)
+		onewire_write_byte(arg, *p++);
+}
+
+void
+onewire_matchrom(void *arg, u_int64_t rom)
+{
+	int i;
+
+	onewire_write_byte(arg, ONEWIRE_CMD_MATCH_ROM);
+	for (i = 0; i < 8; i++)
+		onewire_write_byte(arg, (rom >> (i * 8)) & 0xff);
+}
+
+void
+onewire_thread(void *arg)
+{
+	struct onewire_softc *sc = arg;
+
+	while (!sc->sc_dying) {
+		onewire_scan(sc);
+		tsleep(sc->sc_thread, PWAIT, "owidle", ONEWIRE_SCANTIME * hz);
+	}
+
+	sc->sc_thread = NULL;
+	wakeup(&sc->sc_dying);
+	kthread_exit(0);
+}
+
+void
+onewire_createthread(void *arg)
+{
+	struct onewire_softc *sc = arg;
+
+	if (kthread_create(onewire_thread, sc, &sc->sc_thread,
+	    "%s", sc->sc_dev.dv_xname) != 0)
+		printf("%s: can't create kernel thread\n",
+		    sc->sc_dev.dv_xname);
+}
+
+void
+onewire_scan(struct onewire_softc *sc)
+{
+	struct onewire_device *d, *next, *nd;
+	struct onewire_attach_args oa;
+	struct device *dev;
+	int search = 1, count = 0, present;
+	int dir, rv;
+	u_int64_t mask, rom = 0, lastrom;
+	u_int8_t data[8];
+	int i, i0 = -1;
+
+	TAILQ_FOREACH(d, &sc->sc_devs, d_list)
+		d->d_present = 0;
+
+	while (search && count++ < ONEWIRE_MAXDEVS) {
+		/* XXX: yield processor */
+		tsleep(sc, PWAIT, "owscan", hz / 10);
+
+		/*
+		 * Reset the bus. If there's no presence pulse
+		 * don't search for any devices.
+		 */
+		onewire_lock(sc, 0);
+		if (onewire_reset(sc) != 0) {
+			DPRINTF(("%s: scan: no presence pulse\n",
+			    sc->sc_dev.dv_xname));
+			onewire_unlock(sc);
+			break;
+		}
+
+		/*
+		 * Start new search. Go through the previous path to
+		 * the point we made a decision last time and make an
+		 * opposite decision. If we didn't make any decision
+		 * stop searching.
+		 */
+		search = 0;
+		lastrom = rom;
+		rom = 0;
+		onewire_write_byte(sc, ONEWIRE_CMD_SEARCH_ROM);
+		for (i = 0; i < 64; i++) {
+			dir = (lastrom >> i) & 0x1;
+			if (i == i0)
+				dir = !dir;
+			rv = onewire_triplet(sc, dir);
+			switch (rv) {
+			case 0x0:
+				if (i != i0) {
+					i0 = i;
+					search = 1;
+				}
+				mask = dir;
+				break;
+			case 0x1:
+				mask = 0;
+				break;
+			case 0x2:
+				mask = 1;
+				break;
+			default:
+				DPRINTF(("%s: scan: triplet error 0x%x, "
+				    "step %d\n",
+				    sc->sc_dev.dv_xname, rv, i));
+				onewire_unlock(sc);
+				return;
+			}
+			rom |= (mask << i);
+		}
+		onewire_unlock(sc);
+
+		if (rom == 0)
+			continue;
+
+		/*
+		 * The last byte of the ROM code contains a CRC calculated
+		 * from the first 7 bytes. Re-calculate it to make sure
+		 * we found a valid device.
+		 */
+		for (i = 0; i < 8; i++)
+			data[i] = (rom >> (i * 8)) & 0xff;
+		if (onewire_crc(data, 7) != data[7])
+			continue;
+
+		/*
+		 * Go through the list of attached devices to see if we
+		 * found a new one.
+		 */
+		present = 0;
+		TAILQ_FOREACH(d, &sc->sc_devs, d_list) {
+			if (d->d_rom == rom) {
+				d->d_present = 1;
+				present = 1;
+				break;
+			}
+		}
+		if (!present) {
+			bzero(&oa, sizeof(oa));
+			oa.oa_onewire = sc;
+			oa.oa_rom = rom;
+			if ((dev = config_found(&sc->sc_dev, &oa,
+			    onewire_print)) == NULL)
+				continue;
+
+			MALLOC(nd, struct onewire_device *,
+			    sizeof(struct onewire_device), M_DEVBUF, M_NOWAIT);
+			if (nd == NULL)
+				continue;
+			nd->d_dev = dev;
+			nd->d_rom = rom;
+			nd->d_present = 1;
+			TAILQ_INSERT_TAIL(&sc->sc_devs, nd, d_list);
+		}
+	}
+
+	/* Detach disappeared devices */
+	onewire_lock(sc, 0);
+	for (d = TAILQ_FIRST(&sc->sc_devs);
+	    d != TAILQ_END(&sc->sc_dev); d = next) {
+		next = TAILQ_NEXT(d, d_list);
+		if (!d->d_present) {
+			config_detach(d->d_dev, DETACH_FORCE);
+			TAILQ_REMOVE(&sc->sc_devs, d, d_list);
+			FREE(d, M_DEVBUF);
+		}
+	}
+	onewire_unlock(sc);
+}
diff --git a/sys/dev/onewire/onewire_bitbang.c b/sys/dev/onewire/onewire_bitbang.c
new file mode 100644
index 00000000000..348fb67c4f1
--- /dev/null
+++ b/sys/dev/onewire/onewire_bitbang.c
@@ -0,0 +1,77 @@
+/*	$OpenBSD: onewire_bitbang.c,v 1.1 2006/03/04 16:27:03 grange Exp $	*/
+
+/*
+ * Copyright (c) 2006 Alexander Yurchenko <grange@openbsd.org>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+/*
+ * 1-Wire bus bit-banging routines.
+ */
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/device.h>
+
+#include <dev/onewire/onewirevar.h>
+
+int
+onewire_bb_reset(const struct onewire_bbops *ops, void *arg)
+{
+	int s, rv, i;
+
+	s = splhigh();
+	ops->bb_tx(arg);
+	ops->bb_set(arg, 0);
+	DELAY(480);
+	ops->bb_set(arg, 1);
+	ops->bb_rx(arg);
+	DELAY(30);
+	for (i = 0; i < 6; i++) {
+		if ((rv = ops->bb_get(arg)) == 0)
+			break;
+		DELAY(20);
+	}
+	DELAY(450);
+	splx(s);
+
+	return (rv);
+}
+
+int
+onewire_bb_bit(const struct onewire_bbops *ops, void *arg, int value)
+{
+	int s, rv, i;
+
+	s = splhigh();
+	ops->bb_tx(arg);
+	ops->bb_set(arg, 0);
+	DELAY(2);
+	if (value) {
+		ops->bb_set(arg, 1);
+		ops->bb_rx(arg);
+		for (i = 0; i < 15; i++) {
+			if ((rv = ops->bb_get(arg)) == 0)
+				break;
+			DELAY(2);
+		}
+		ops->bb_tx(arg);
+	}
+	DELAY(60);
+	ops->bb_set(arg, 1);
+	DELAY(5);
+	splx(s);
+
+	return (rv);
+}
diff --git a/sys/dev/onewire/onewire_subr.c b/sys/dev/onewire/onewire_subr.c
new file mode 100644
index 00000000000..f20e4913914
--- /dev/null
+++ b/sys/dev/onewire/onewire_subr.c
@@ -0,0 +1,112 @@
+/*	$OpenBSD: onewire_subr.c,v 1.1 2006/03/04 16:27:03 grange Exp $	*/
+
+/*
+ * Copyright (c) 2006 Alexander Yurchenko <grange@openbsd.org>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+/*
+ * 1-Wire bus miscellaneous routines.
+ */
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/device.h>
+
+#include <dev/onewire/onewiredevs.h>
+#include <dev/onewire/onewirereg.h>
+#include <dev/onewire/onewirevar.h>
+
+#ifdef ONEWIREVERBOSE
+struct onewire_family {
+	int		of_type;
+	const char *	of_name;
+};
+#include <dev/onewire/onewiredevs_data.h>
+#endif
+
+static const u_int8_t crctable[] = {
+	0x00, 0x5e, 0xbc, 0xe2, 0x61, 0x3f, 0xdd, 0x83,
+	0xc2, 0x9c, 0x7e, 0x20, 0xa3, 0xfd, 0x1f, 0x41,
+	0x9d, 0xc3, 0x21, 0x7f, 0xfc, 0xa2, 0x40, 0x1e,
+	0x5f, 0x01, 0xe3, 0xbd, 0x3e, 0x60, 0x82, 0xdc,
+	0x23, 0x7d, 0x9f, 0xc1, 0x42, 0x1c, 0xfe, 0xa0,
+	0xe1, 0xbf, 0x5d, 0x03, 0x80, 0xde, 0x3c, 0x62,
+	0xbe, 0xe0, 0x02, 0x5c, 0xdf, 0x81, 0x63, 0x3d,
+	0x7c, 0x22, 0xc0, 0x9e, 0x1d, 0x43, 0xa1, 0xff,
+	0x46, 0x18, 0xfa, 0xa4, 0x27, 0x79, 0x9b, 0xc5,
+	0x84, 0xda, 0x38, 0x66, 0xe5, 0xbb, 0x59, 0x07,
+	0xdb, 0x85, 0x67, 0x39, 0xba, 0xe4, 0x06, 0x58,
+	0x19, 0x47, 0xa5, 0xfb, 0x78, 0x26, 0xc4, 0x9a,
+	0x65, 0x3b, 0xd9, 0x87, 0x04, 0x5a, 0xb8, 0xe6,
+	0xa7, 0xf9, 0x1b, 0x45, 0xc6, 0x98, 0x7a, 0x24,
+	0xf8, 0xa6, 0x44, 0x1a, 0x99, 0xc7, 0x25, 0x7b,
+	0x3a, 0x64, 0x86, 0xd8, 0x5b, 0x05, 0xe7, 0xb9,
+	0x8c, 0xd2, 0x30, 0x6e, 0xed, 0xb3, 0x51, 0x0f,
+	0x4e, 0x10, 0xf2, 0xac, 0x2f, 0x71, 0x93, 0xcd,
+	0x11, 0x4f, 0xad, 0xf3, 0x70, 0x2e, 0xcc, 0x92,
+	0xd3, 0x8d, 0x6f, 0x31, 0xb2, 0xec, 0x0e, 0x50,
+	0xaf, 0xf1, 0x13, 0x4d, 0xce, 0x90, 0x72, 0x2c,
+	0x6d, 0x33, 0xd1, 0x8f, 0x0c, 0x52, 0xb0, 0xee,
+	0x32, 0x6c, 0x8e, 0xd0, 0x53, 0x0d, 0xef, 0xb1,
+	0xf0, 0xae, 0x4c, 0x12, 0x91, 0xcf, 0x2d, 0x73,
+	0xca, 0x94, 0x76, 0x28, 0xab, 0xf5, 0x17, 0x49,
+	0x08, 0x56, 0xb4, 0xea, 0x69, 0x37, 0xd5, 0x8b,
+	0x57, 0x09, 0xeb, 0xb5, 0x36, 0x68, 0x8a, 0xd4,
+	0x95, 0xcb, 0x29, 0x77, 0xf4, 0xaa, 0x48, 0x16,
+	0xe9, 0xb7, 0x55, 0x0b, 0x88, 0xd6, 0x34, 0x6a,
+	0x2b, 0x75, 0x97, 0xc9, 0x4a, 0x14, 0xf6, 0xa8,
+	0x74, 0x2a, 0xc8, 0x96, 0x15, 0x4b, 0xa9, 0xf7,
+	0xb6, 0xe8, 0x0a, 0x54, 0xd7, 0x89, 0x6b, 0x35
+};
+
+int
+onewire_crc(const void *buf, int len)
+{
+	const u_int8_t *p = buf;
+	u_int8_t crc = 0;
+
+	while (len--)
+		crc = crctable[crc ^ *p++];
+
+	return (crc);
+}
+
+const char *
+onewire_famname(int type)
+{
+#ifdef ONEWIREVERBOSE
+	const struct onewire_family *of;
+
+	for (of = onewire_famtab; of->of_name != NULL; of++)
+		if (of->of_type == type)
+			return (of->of_name);
+#endif
+
+	return (NULL);
+}
+
+int
+onewire_matchbyfam(struct onewire_attach_args *oa,
+    const struct onewire_matchfam *fams, int nent)
+{
+	const struct onewire_matchfam *om;
+	int i;
+
+	for (i = 0, om = fams; i < nent; i++, om++)
+		if (ONEWIRE_ROM_FAMILY_TYPE(oa->oa_rom) == om->om_type)
+			return (1);
+
+	return (0);
+}
diff --git a/sys/dev/onewire/onewiredevs b/sys/dev/onewire/onewiredevs
new file mode 100644
index 00000000000..4ff79e5d0b5
--- /dev/null
+++ b/sys/dev/onewire/onewiredevs
@@ -0,0 +1,31 @@
+$OpenBSD: onewiredevs,v 1.1 2006/03/04 16:27:03 grange Exp $
+
+/*
+ * Copyright (c) 2006 Alexander Yurchenko <grange@openbsd.org>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+/*
+ * List of known 1-Wire family types.
+ */
+
+family	DS1990		0x01	ID
+family	DS1991		0x02	MultiKey
+family	DS1994		0x04	4kb NVRAM + RTC
+family	DS1993		0x06	4kb NVRAM
+family	DS1992		0x08	1kb NVRAM
+family	DS1982		0x09	1kb EPROM
+family	DS1995		0x0a	16kb NVRAM
+family	DS1996		0x0c	64kb NVRAM
+family	DS1920		0x10	Temperature
diff --git a/sys/dev/onewire/onewirereg.h b/sys/dev/onewire/onewirereg.h
new file mode 100644
index 00000000000..6462e8db696
--- /dev/null
+++ b/sys/dev/onewire/onewirereg.h
@@ -0,0 +1,72 @@
+/*	$OpenBSD: onewirereg.h,v 1.1 2006/03/04 16:27:03 grange Exp $	*/
+
+/*
+ * Copyright (c) 2006 Alexander Yurchenko <grange@openbsd.org>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#ifndef _DEV_ONEWIRE_ONEWIREREG_H_
+#define _DEV_ONEWIRE_ONEWIREREG_H_
+
+/*
+ * 1-Wire bus protocol definitions.
+ */
+
+/*
+ * 64-bit ROM section.
+ */
+
+/* Family code */
+#define ONEWIRE_ROM_FAMILY(x)		((x) & 0xff)
+#define ONEWIRE_ROM_FAMILY_TYPE(x)	((x) & 0x7f)
+#define ONEWIRE_ROM_FAMILY_CUSTOM(x)	(((x) >> 7) & 0x1)
+
+/* Serial number */
+#define ONEWIRE_ROM_SN(x)		(((x) >> 8) & 0xffffffffffffULL)
+
+/* CRC */
+#define ONEWIRE_ROM_CRC(x)		(((x) >> 56) & 0xff)
+
+/*
+ * Command set.
+ */
+
+/* ROM commands */
+#define ONEWIRE_CMD_READ_ROM		0x33
+#define ONEWIRE_CMD_SKIP_ROM		0xcc
+#define ONEWIRE_CMD_MATCH_ROM		0x55
+#define ONEWIRE_CMD_SEARCH_ROM		0xf0
+#define ONEWIRE_CMD_OVERDRIVE_SKIP_ROM	0x3c
+#define ONEWIRE_CMD_OVERDRIVE_MATCH_ROM	0x69
+
+/* Scratchpad commands */
+#define ONEWIRE_CMD_READ_SCRATCHPAD	0xaa
+#define ONEWIRE_CMD_WRITE_SCRATCHPAD	0x0f
+#define ONEWIRE_CMD_COPY_SCRATCHPAD	0x55
+
+/* Memory commands */
+#define ONEWIRE_CMD_READ_MEMORY		0xf0
+#define ONEWIRE_CMD_WRITE_MEMORY	0x0f
+#define ONEWIRE_CMD_EXT_READ_MEMORY	0xa5
+
+/* Password commands */
+#define ONEWIRE_CMD_READ_SUBKEY		0x66
+#define ONEWIRE_CMD_WRITE_SUBKEY	0x99
+#define ONEWIRE_CMD_WRITE_PASSWORD	0x5a
+
+/* Status commands */
+#define ONEWIRE_CMD_READ_STATUS		0xaa
+#define ONEWIRE_CMD_WRITE_STATUS	0x55
+
+#endif	/* !_DEV_ONEWIRE_ONEWIREREG_H_ */
diff --git a/sys/dev/onewire/onewirevar.h b/sys/dev/onewire/onewirevar.h
new file mode 100644
index 00000000000..51b7ea4a434
--- /dev/null
+++ b/sys/dev/onewire/onewirevar.h
@@ -0,0 +1,86 @@
+/*	$OpenBSD: onewirevar.h,v 1.1 2006/03/04 16:27:03 grange Exp $	*/
+
+/*
+ * Copyright (c) 2006 Alexander Yurchenko <grange@openbsd.org>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#ifndef _DEV_ONEWIRE_ONEWIREVAR_H_
+#define _DEV_ONEWIRE_ONEWIREVAR_H_
+
+/*
+ * 1-Wire bus interface.
+ */
+
+/* Bus master interface */
+struct onewire_bus {
+	void *	bus_cookie;
+
+	int	(*bus_reset)(void *);
+	int	(*bus_bit)(void *, int);
+	int	(*bus_read_byte)(void *);
+	void	(*bus_write_byte)(void *, int);
+	int	(*bus_triplet)(void *, int);
+};
+
+/* Bus methods */
+int		onewire_lock(void *, int);
+void		onewire_unlock(void *);
+int		onewire_reset(void *);
+int		onewire_bit(void *, int);
+int		onewire_read_byte(void *);
+void		onewire_write_byte(void *, int);
+int		onewire_triplet(void *, int);
+void		onewire_read_block(void *, void *, int);
+void		onewire_write_block(void *, const void *, int);
+void		onewire_matchrom(void *, u_int64_t);
+
+#define ONEWIRE_NOWAIT		0x0001
+
+/* Bus attachment */
+struct onewirebus_attach_args {
+	struct onewire_bus *	oba_bus;
+};
+
+int	onewirebus_print(void *, const char *);
+
+/* Device attachment */
+struct onewire_attach_args {
+	void *			oa_onewire;
+	u_int64_t		oa_rom;
+};
+
+/* Family matching */
+struct onewire_matchfam {
+	int om_type;
+};
+
+/* Miscellaneous routines */
+int		onewire_crc(const void *, int);
+const char *	onewire_famname(int);
+int		onewire_matchbyfam(struct onewire_attach_args *,
+		    const struct onewire_matchfam *, int);
+
+/* Bus bit-banging */
+struct onewire_bbops {
+	void	(*bb_rx)(void *);
+	void	(*bb_tx)(void *);
+	int	(*bb_get)(void *);
+	void	(*bb_set)(void *, int);
+};
+
+int		onewire_bb_reset(const struct onewire_bbops *, void *);
+int		onewire_bb_bit(const struct onewire_bbops *, void *, int);
+
+#endif	/* !_DEV_ONEWIRE_ONEWIREVAR_H_ */
diff --git a/sys/dev/onewire/owid.c b/sys/dev/onewire/owid.c
new file mode 100644
index 00000000000..21fdb9e8b3c
--- /dev/null
+++ b/sys/dev/onewire/owid.c
@@ -0,0 +1,117 @@
+/*	$OpenBSD: owid.c,v 1.1 2006/03/04 16:27:03 grange Exp $	*/
+
+/*
+ * Copyright (c) 2006 Alexander Yurchenko <grange@openbsd.org>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+/*
+ * 1-Wire ID family type device driver.
+ */
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/device.h>
+#include <sys/kernel.h>
+#include <sys/proc.h>
+#include <sys/sensors.h>
+
+#include <dev/onewire/onewiredevs.h>
+#include <dev/onewire/onewirereg.h>
+#include <dev/onewire/onewirevar.h>
+
+struct owid_softc {
+	struct device		sc_dev;
+
+	void *			sc_onewire;
+	u_int64_t		sc_rom;
+
+	struct sensor		sc_sensor;
+
+	int			sc_dying;
+};
+
+int	owid_match(struct device *, void *, void *);
+void	owid_attach(struct device *, struct device *, void *);
+int	owid_detach(struct device *, int);
+int	owid_activate(struct device *, enum devact);
+
+struct cfattach owid_ca = {
+	sizeof(struct owid_softc),
+	owid_match,
+	owid_attach,
+	owid_detach,
+	owid_activate
+};
+
+struct cfdriver owid_cd = {
+	NULL, "owid", DV_DULL
+};
+
+static const struct onewire_matchfam owid_fams[] = {
+	{ ONEWIRE_FAMILY_DS1990 }
+};
+
+int
+owid_match(struct device *parent, void *match, void *aux)
+{
+	return (onewire_matchbyfam(aux, owid_fams,
+	    sizeof(owid_fams) /sizeof(owid_fams[0])));
+}
+
+void
+owid_attach(struct device *parent, struct device *self, void *aux)
+{
+	struct owid_softc *sc = (struct owid_softc *)self;
+	struct onewire_attach_args *oa = aux;
+
+	sc->sc_onewire = oa->oa_onewire;
+	sc->sc_rom = oa->oa_rom;
+
+	/* Initialize sensor */
+	strlcpy(sc->sc_sensor.device, sc->sc_dev.dv_xname,
+	    sizeof(sc->sc_sensor.device));
+	sc->sc_sensor.type = SENSOR_INTEGER;
+	strlcpy(sc->sc_sensor.desc, "ID", sizeof(sc->sc_sensor.desc));
+	sc->sc_sensor.value = ONEWIRE_ROM_SN(sc->sc_rom);
+	sensor_add(&sc->sc_sensor);
+
+	printf("\n");
+}
+
+int
+owid_detach(struct device *self, int flags)
+{
+	struct owid_softc *sc = (struct owid_softc *)self;
+
+	sensor_del(&sc->sc_sensor);
+
+	return (0);
+}
+
+int
+owid_activate(struct device *self, enum devact act)
+{
+	struct owid_softc *sc = (struct owid_softc *)self;
+
+	switch (act) {
+	case DVACT_ACTIVATE:
+		return (EOPNOTSUPP);
+	case DVACT_DEACTIVATE:
+		sc->sc_dying = 1;
+		break;
+	}
+
+	return (0);
+}
diff --git a/sys/dev/onewire/owtemp.c b/sys/dev/onewire/owtemp.c
new file mode 100644
index 00000000000..1fd5b673881
--- /dev/null
+++ b/sys/dev/onewire/owtemp.c
@@ -0,0 +1,167 @@
+/*	$OpenBSD: owtemp.c,v 1.1 2006/03/04 16:27:03 grange Exp $	*/
+
+/*
+ * Copyright (c) 2006 Alexander Yurchenko <grange@openbsd.org>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+/*
+ * 1-Wire temperature family type device driver.
+ */
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/device.h>
+#include <sys/kernel.h>
+#include <sys/proc.h>
+#include <sys/sensors.h>
+
+#include <dev/onewire/onewiredevs.h>
+#include <dev/onewire/onewirereg.h>
+#include <dev/onewire/onewirevar.h>
+
+#define DS1920_CMD_CONVERT		0x44
+#define DS1920_CMD_READ_SCRATCHPAD	0xbe
+
+struct owtemp_softc {
+	struct device		sc_dev;
+
+	void *			sc_onewire;
+	u_int64_t		sc_rom;
+
+	struct sensor		sc_sensor;
+
+	int			sc_dying;
+};
+
+int	owtemp_match(struct device *, void *, void *);
+void	owtemp_attach(struct device *, struct device *, void *);
+int	owtemp_detach(struct device *, int);
+int	owtemp_activate(struct device *, enum devact);
+
+void	owtemp_update(void *);
+
+struct cfattach owtemp_ca = {
+	sizeof(struct owtemp_softc),
+	owtemp_match,
+	owtemp_attach,
+	owtemp_detach,
+	owtemp_activate
+};
+
+struct cfdriver owtemp_cd = {
+	NULL, "owtemp", DV_DULL
+};
+
+static const struct onewire_matchfam owtemp_fams[] = {
+	{ ONEWIRE_FAMILY_DS1920 }
+};
+
+int
+owtemp_match(struct device *parent, void *match, void *aux)
+{
+	return (onewire_matchbyfam(aux, owtemp_fams,
+	    sizeof(owtemp_fams) /sizeof(owtemp_fams[0])));
+}
+
+void
+owtemp_attach(struct device *parent, struct device *self, void *aux)
+{
+	struct owtemp_softc *sc = (struct owtemp_softc *)self;
+	struct onewire_attach_args *oa = aux;
+
+	sc->sc_onewire = oa->oa_onewire;
+	sc->sc_rom = oa->oa_rom;
+
+	/* Initialize sensor */
+	strlcpy(sc->sc_sensor.device, sc->sc_dev.dv_xname,
+	    sizeof(sc->sc_sensor.device));
+	sc->sc_sensor.type = SENSOR_TEMP;
+	strlcpy(sc->sc_sensor.desc, "Temp", sizeof(sc->sc_sensor.desc));
+
+	if (sensor_task_register(sc, owtemp_update, 5)) {
+		printf(": unable to register update task\n");
+		return;
+	}
+	sensor_add(&sc->sc_sensor);
+
+	printf("\n");
+}
+
+int
+owtemp_detach(struct device *self, int flags)
+{
+	struct owtemp_softc *sc = (struct owtemp_softc *)self;
+
+	sensor_del(&sc->sc_sensor);
+	sensor_task_unregister(sc);
+
+	return (0);
+}
+
+int
+owtemp_activate(struct device *self, enum devact act)
+{
+	struct owtemp_softc *sc = (struct owtemp_softc *)self;
+
+	switch (act) {
+	case DVACT_ACTIVATE:
+		return (EOPNOTSUPP);
+	case DVACT_DEACTIVATE:
+		sc->sc_dying = 1;
+		break;
+	}
+
+	return (0);
+}
+
+void
+owtemp_update(void *arg)
+{
+	struct owtemp_softc *sc = arg;
+	u_int8_t data[9];
+
+	onewire_lock(sc->sc_onewire, 0);
+	if (onewire_reset(sc->sc_onewire) != 0)
+		goto done;
+	onewire_matchrom(sc->sc_onewire, sc->sc_rom);
+
+	/*
+	 * Start temperature conversion. The conversion takes up to 750ms.
+	 * After sending the command, the data line must be held high for
+	 * at least 750ms to provide power during the conversion process.
+	 * As such, no other activity may take place on the 1-Wire bus for
+	 * at least this period.
+	 */
+	onewire_write_byte(sc->sc_onewire, DS1920_CMD_CONVERT);
+	tsleep(sc, PRIBIO, "owtemp", hz);
+
+	if (onewire_reset(sc->sc_onewire) != 0)
+		goto done;
+	onewire_matchrom(sc->sc_onewire, sc->sc_rom);
+
+	/*
+	 * The result of the temperature measurement is placed in the
+	 * first two bytes of the scratchpad.
+	 */
+	onewire_write_byte(sc->sc_onewire, DS1920_CMD_READ_SCRATCHPAD);
+	onewire_read_block(sc->sc_onewire, data, 9);
+	if (onewire_crc(data, 8) == data[8]) {
+		sc->sc_sensor.value = 273150000 +
+		    (int)((u_int16_t)data[1] << 8 | data[0]) * 500000;
+	}
+
+done:
+	onewire_unlock(sc->sc_onewire);
+}