Driver for the Intel 82801AA (ICH) SMBus controller and compatibles.

Obtained from:	Whistle source tree

1 files changed, 682 insertions, 0 deletions

diff --git a/sys/dev/ichsmb/ichsmb.c b/sys/dev/ichsmb/ichsmb.c
new file mode 100644
index 0000000..c261c02
--- /dev/null
+++ b/sys/dev/ichsmb/ichsmb.c
@@ -0,0 +1,682 @@
+
+/*
+ * ichsmb.c
+ *
+ * Copyright (c) 2000 Whistle Communications, Inc.
+ * All rights reserved.
+ * 
+ * Subject to the following obligations and disclaimer of warranty, use and
+ * redistribution of this software, in source or object code forms, with or
+ * without modifications are expressly permitted by Whistle Communications;
+ * provided, however, that:
+ * 1. Any and all reproductions of the source or object code must include the
+ *    copyright notice above and the following disclaimer of warranties; and
+ * 2. No rights are granted, in any manner or form, to use Whistle
+ *    Communications, Inc. trademarks, including the mark "WHISTLE
+ *    COMMUNICATIONS" on advertising, endorsements, or otherwise except as
+ *    such appears in the above copyright notice or in the software.
+ * 
+ * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
+ * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
+ * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
+ * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
+ * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
+ * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
+ * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
+ * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
+ * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
+ * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
+ * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
+ * OF SUCH DAMAGE.
+ *
+ * Author: Archie Cobbs <archie@freebsd.org>
+ *
+ * $FreeBSD$
+ */
+
+/*
+ * Support for the SMBus controller logical device which is part of the
+ * Intel 81801AA (ICH) and 81801AB (ICH0) I/O controller hub chips.
+ */
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/kernel.h>
+#include <sys/errno.h>
+#include <sys/syslog.h>
+#include <sys/bus.h>
+
+#include <machine/bus.h>
+#include <sys/rman.h>
+#include <machine/resource.h>
+
+#include <dev/smbus/smbconf.h>
+
+#include <dev/ichsmb/ichsmb_var.h>
+#include <dev/ichsmb/ichsmb_reg.h>
+
+/*
+ * Enable debugging by defining ICHSMB_DEBUG to a non-zero value.
+ */
+#define ICHSMB_DEBUG	0
+#if ICHSMB_DEBUG != 0 && defined(__GNUC__)
+#define DBG(fmt, args...)	\
+	do { log(LOG_DEBUG, "%s: " fmt, __FUNCTION__ , ## args); } while (0)
+#else
+#define DBG(fmt, args...)	do { } while (0)
+#endif
+
+/*
+ * Our child device driver name
+ */
+#define DRIVER_SMBUS	"smbus"
+
+/*
+ * Internal functions
+ */
+static int ichsmb_wait(sc_p sc);
+
+/********************************************************************
+		BUS-INDEPENDENT BUS METHODS
+********************************************************************/
+
+/*
+ * Handle probe-time duties that are independent of the bus
+ * our device lives on.
+ */
+int
+ichsmb_probe(device_t dev)
+{
+	device_t smb;
+
+	/* Add child: an instance of the "smbus" device */
+	if ((smb = device_add_child(dev, DRIVER_SMBUS, -1)) == NULL) {
+		log(LOG_ERR, "%s: no \"%s\" child found\n",
+		    device_get_nameunit(dev), DRIVER_SMBUS);
+		return (ENXIO);
+	}
+	return (0);
+}
+
+/*
+ * Handle attach-time duties that are independent of the bus
+ * our device lives on.
+ */
+int
+ichsmb_attach(device_t dev)
+{
+	const sc_p sc = device_get_softc(dev);
+	int error;
+
+	/* Clear interrupt conditions */
+	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_HST_STA, 0xff);
+
+	/* Add "smbus" child */
+	if ((error = bus_generic_attach(dev)) != 0) {
+		log(LOG_ERR, "%s: failed to attach child: %d\n",
+		    device_get_nameunit(dev), error);
+		error = ENXIO;
+	}
+
+	/* Done */
+	return (error);
+}
+
+/********************************************************************
+			SMBUS METHODS
+********************************************************************/
+
+int 
+ichsmb_callback(device_t dev, int index, caddr_t data)
+{
+	int smb_error = 0;
+
+	DBG("index=%d how=%d\n", index, data ? *(int *)data : -1);
+	switch (index) {
+	case SMB_REQUEST_BUS:
+		break;
+	case SMB_RELEASE_BUS:
+		break;
+	default:
+		smb_error = SMB_EABORT;	/* XXX */
+		break;
+	}
+	DBG("smb_error=%d\n", smb_error);
+	return (smb_error);
+}
+
+int
+ichsmb_quick(device_t dev, u_char slave, int how)
+{
+	const sc_p sc = device_get_softc(dev);
+	int smb_error;
+	int s;
+
+	DBG("slave=0x%02x how=%d\n", slave, how);
+	KASSERT(sc->ich_cmd == -1,
+	    ("%s: ich_cmd=%d\n", __FUNCTION__ , sc->ich_cmd));
+	switch (how) {
+	case SMB_QREAD:
+	case SMB_QWRITE:
+		s = splhigh();
+		sc->ich_cmd = ICH_HST_CNT_SMB_CMD_QUICK;
+		bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_XMIT_SLVA,
+		    (slave << 1) | (how == SMB_QREAD ?
+	    		ICH_XMIT_SLVA_READ : ICH_XMIT_SLVA_WRITE));
+		bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_HST_CNT,
+		    ICH_HST_CNT_START | ICH_HST_CNT_INTREN | sc->ich_cmd);
+		smb_error = ichsmb_wait(sc);
+		splx(s);
+		break;
+	default:
+		smb_error = SMB_ENOTSUPP;
+	}
+	DBG("smb_error=%d\n", smb_error);
+	return (smb_error);
+}
+
+int
+ichsmb_sendb(device_t dev, u_char slave, char byte)
+{
+	const sc_p sc = device_get_softc(dev);
+	int smb_error;
+	int s;
+
+	DBG("slave=0x%02x byte=0x%02x\n", slave, (u_char)byte);
+	KASSERT(sc->ich_cmd == -1,
+	    ("%s: ich_cmd=%d\n", __FUNCTION__ , sc->ich_cmd));
+	s = splhigh();
+	sc->ich_cmd = ICH_HST_CNT_SMB_CMD_BYTE;
+	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_XMIT_SLVA,
+	    (slave << 1) | ICH_XMIT_SLVA_WRITE);
+	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_HST_CMD, byte);
+	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_HST_CNT,
+	    ICH_HST_CNT_START | ICH_HST_CNT_INTREN | sc->ich_cmd);
+	smb_error = ichsmb_wait(sc);
+	splx(s);
+	DBG("smb_error=%d\n", smb_error);
+	return (smb_error);
+}
+
+int
+ichsmb_recvb(device_t dev, u_char slave, char *byte)
+{
+	const sc_p sc = device_get_softc(dev);
+	int smb_error;
+	int s;
+
+	DBG("slave=0x%02x\n", slave);
+	KASSERT(sc->ich_cmd == -1,
+	    ("%s: ich_cmd=%d\n", __FUNCTION__ , sc->ich_cmd));
+	s = splhigh();
+	sc->ich_cmd = ICH_HST_CNT_SMB_CMD_BYTE;
+	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_XMIT_SLVA,
+	    (slave << 1) | ICH_XMIT_SLVA_READ);
+	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_HST_CNT,
+	    ICH_HST_CNT_START | ICH_HST_CNT_INTREN | sc->ich_cmd);
+	if ((smb_error = ichsmb_wait(sc)) == SMB_ENOERR)
+		*byte = bus_space_read_1(sc->io_bst, sc->io_bsh, ICH_D0);
+	splx(s);
+	DBG("smb_error=%d byte=0x%02x\n", smb_error, (u_char)*byte);
+	return (smb_error);
+}
+
+int
+ichsmb_writeb(device_t dev, u_char slave, char cmd, char byte)
+{
+	const sc_p sc = device_get_softc(dev);
+	int smb_error;
+	int s;
+
+	DBG("slave=0x%02x cmd=0x%02x byte=0x%02x\n",
+	    slave, (u_char)cmd, (u_char)byte);
+	KASSERT(sc->ich_cmd == -1,
+	    ("%s: ich_cmd=%d\n", __FUNCTION__ , sc->ich_cmd));
+	s = splhigh();
+	sc->ich_cmd = ICH_HST_CNT_SMB_CMD_BYTE_DATA;
+	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_XMIT_SLVA,
+	    (slave << 1) | ICH_XMIT_SLVA_WRITE);
+	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_HST_CMD, cmd);
+	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_D0, byte);
+	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_HST_CNT,
+	    ICH_HST_CNT_START | ICH_HST_CNT_INTREN | sc->ich_cmd);
+	smb_error = ichsmb_wait(sc);
+	splx(s);
+	DBG("smb_error=%d\n", smb_error);
+	return (smb_error);
+}
+
+int
+ichsmb_writew(device_t dev, u_char slave, char cmd, short word)
+{
+	const sc_p sc = device_get_softc(dev);
+	int smb_error;
+	int s;
+
+	DBG("slave=0x%02x cmd=0x%02x word=0x%04x\n",
+	    slave, (u_char)cmd, (u_int16_t)word);
+	KASSERT(sc->ich_cmd == -1,
+	    ("%s: ich_cmd=%d\n", __FUNCTION__ , sc->ich_cmd));
+	s = splhigh();
+	sc->ich_cmd = ICH_HST_CNT_SMB_CMD_WORD_DATA;
+	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_XMIT_SLVA,
+	    (slave << 1) | ICH_XMIT_SLVA_WRITE);
+	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_HST_CMD, cmd);
+	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_D0, word & 0xff);
+	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_D1, word >> 8);
+	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_HST_CNT,
+	    ICH_HST_CNT_START | ICH_HST_CNT_INTREN | sc->ich_cmd);
+	smb_error = ichsmb_wait(sc);
+	splx(s);
+	DBG("smb_error=%d\n", smb_error);
+	return (smb_error);
+}
+
+int
+ichsmb_readb(device_t dev, u_char slave, char cmd, char *byte)
+{
+	const sc_p sc = device_get_softc(dev);
+	int smb_error;
+	int s;
+
+	DBG("slave=0x%02x cmd=0x%02x\n", slave, (u_char)cmd);
+	KASSERT(sc->ich_cmd == -1,
+	    ("%s: ich_cmd=%d\n", __FUNCTION__ , sc->ich_cmd));
+	s = splhigh();
+	sc->ich_cmd = ICH_HST_CNT_SMB_CMD_BYTE_DATA;
+	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_XMIT_SLVA,
+	    (slave << 1) | ICH_XMIT_SLVA_READ);
+	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_HST_CMD, cmd);
+	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_HST_CNT,
+	    ICH_HST_CNT_START | ICH_HST_CNT_INTREN | sc->ich_cmd);
+	if ((smb_error = ichsmb_wait(sc)) == SMB_ENOERR)
+		*byte = bus_space_read_1(sc->io_bst, sc->io_bsh, ICH_D0);
+	splx(s);
+	DBG("smb_error=%d byte=0x%02x\n", smb_error, (u_char)*byte);
+	return (smb_error);
+}
+
+int
+ichsmb_readw(device_t dev, u_char slave, char cmd, short *word)
+{
+	const sc_p sc = device_get_softc(dev);
+	int smb_error;
+	int s;
+
+	DBG("slave=0x%02x cmd=0x%02x\n", slave, (u_char)cmd);
+	KASSERT(sc->ich_cmd == -1,
+	    ("%s: ich_cmd=%d\n", __FUNCTION__ , sc->ich_cmd));
+	s = splhigh();
+	sc->ich_cmd = ICH_HST_CNT_SMB_CMD_WORD_DATA;
+	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_XMIT_SLVA,
+	    (slave << 1) | ICH_XMIT_SLVA_READ);
+	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_HST_CMD, cmd);
+	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_HST_CNT,
+	    ICH_HST_CNT_START | ICH_HST_CNT_INTREN | sc->ich_cmd);
+	if ((smb_error = ichsmb_wait(sc)) == SMB_ENOERR) {
+		*word = (bus_space_read_1(sc->io_bst,
+			sc->io_bsh, ICH_D0) & 0xff)
+		  | (bus_space_read_1(sc->io_bst,
+			sc->io_bsh, ICH_D1) << 8);
+	}
+	splx(s);
+	DBG("smb_error=%d word=0x%04x\n", smb_error, (u_int16_t)*word);
+	return (smb_error);
+}
+
+int
+ichsmb_pcall(device_t dev, u_char slave, char cmd, short sdata, short *rdata)
+{
+	const sc_p sc = device_get_softc(dev);
+	int smb_error;
+	int s;
+
+	DBG("slave=0x%02x cmd=0x%02x sdata=0x%04x\n",
+	    slave, (u_char)cmd, (u_int16_t)sdata);
+	KASSERT(sc->ich_cmd == -1,
+	    ("%s: ich_cmd=%d\n", __FUNCTION__ , sc->ich_cmd));
+	s = splhigh();
+	sc->ich_cmd = ICH_HST_CNT_SMB_CMD_PROC_CALL;
+	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_XMIT_SLVA,
+	    (slave << 1) | ICH_XMIT_SLVA_WRITE);
+	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_HST_CMD, cmd);
+	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_D0, sdata & 0xff);
+	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_D1, sdata >> 8);
+	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_HST_CNT,
+	    ICH_HST_CNT_START | ICH_HST_CNT_INTREN | sc->ich_cmd);
+	if ((smb_error = ichsmb_wait(sc)) == SMB_ENOERR) {
+		*rdata = (bus_space_read_1(sc->io_bst,
+			sc->io_bsh, ICH_D0) & 0xff)
+		  | (bus_space_read_1(sc->io_bst,
+			sc->io_bsh, ICH_D1) << 8);
+	}
+	splx(s);
+	DBG("smb_error=%d rdata=0x%04x\n", smb_error, (u_int16_t)*rdata);
+	return (smb_error);
+}
+
+int
+ichsmb_bwrite(device_t dev, u_char slave, char cmd, u_char count, char *buf)
+{
+	const sc_p sc = device_get_softc(dev);
+	int smb_error;
+	int s;
+
+	DBG("slave=0x%02x cmd=0x%02x count=%d\n", slave, (u_char)cmd, count);
+#if ICHSMB_DEBUG
+#define DISP(ch)	(((ch) < 0x20 || (ch) >= 0x7e) ? '.' : (ch))
+	{
+	    u_char *p;
+
+	    for (p = (u_char *)buf; p - (u_char *)buf < 32; p += 8) {
+		DBG("%02x: %02x %02x %02x %02x %02x %02x %02x %02x"
+		    "  %c%c%c%c%c%c%c%c", (p - (u_char *)buf),
+		    p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7],
+		    DISP(p[0]), DISP(p[1]), DISP(p[2]), DISP(p[3]), 
+		    DISP(p[4]), DISP(p[5]), DISP(p[6]), DISP(p[7]));
+	    }
+	}
+#undef DISP
+#endif
+	KASSERT(sc->ich_cmd == -1,
+	    ("%s: ich_cmd=%d\n", __FUNCTION__ , sc->ich_cmd));
+	if (count < 1 || count > 32)
+		return (EINVAL);
+	bcopy(buf, sc->block_data, count);
+	sc->block_count = count;
+	sc->block_index = 1;
+	sc->block_write = 1;
+
+	s = splhigh();
+	sc->ich_cmd = ICH_HST_CNT_SMB_CMD_BLOCK;
+	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_XMIT_SLVA,
+	    (slave << 1) | ICH_XMIT_SLVA_WRITE);
+	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_HST_CMD, cmd);
+	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_D0, count);
+	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_BLOCK_DB, buf[0]);
+	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_HST_CNT,
+	    ICH_HST_CNT_START | ICH_HST_CNT_INTREN | sc->ich_cmd);
+	smb_error = ichsmb_wait(sc);
+	splx(s);
+	DBG("smb_error=%d\n", smb_error);
+	return (smb_error);
+}
+
+int
+ichsmb_bread(device_t dev, u_char slave, char cmd, u_char count, char *buf)
+{
+	const sc_p sc = device_get_softc(dev);
+	int smb_error;
+	int s;
+
+	DBG("slave=0x%02x cmd=0x%02x count=%d\n", slave, (u_char)cmd, count);
+	KASSERT(sc->ich_cmd == -1,
+	    ("%s: ich_cmd=%d\n", __FUNCTION__ , sc->ich_cmd));
+	if (count < 1 || count > 32)
+		return (EINVAL);
+	bzero(sc->block_data, sizeof(sc->block_data));
+	sc->block_count = count;
+	sc->block_index = 0;
+	sc->block_write = 0;
+
+	s = splhigh();
+	sc->ich_cmd = ICH_HST_CNT_SMB_CMD_BLOCK;
+	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_XMIT_SLVA,
+	    (slave << 1) | ICH_XMIT_SLVA_READ);
+	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_HST_CMD, cmd);
+	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_D0, count); /* XXX? */
+	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_HST_CNT,
+	    ICH_HST_CNT_START | ICH_HST_CNT_INTREN | sc->ich_cmd);
+	if ((smb_error = ichsmb_wait(sc)) == SMB_ENOERR)
+		bcopy(sc->block_data, buf, sc->block_count);
+	splx(s);
+	DBG("smb_error=%d\n", smb_error);
+#if ICHSMB_DEBUG
+#define DISP(ch)	(((ch) < 0x20 || (ch) >= 0x7e) ? '.' : (ch))
+	{
+	    u_char *p;
+
+	    for (p = (u_char *)buf; p - (u_char *)buf < 32; p += 8) {
+		DBG("%02x: %02x %02x %02x %02x %02x %02x %02x %02x"
+		    "  %c%c%c%c%c%c%c%c", (p - (u_char *)buf),
+		    p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7],
+		    DISP(p[0]), DISP(p[1]), DISP(p[2]), DISP(p[3]), 
+		    DISP(p[4]), DISP(p[5]), DISP(p[6]), DISP(p[7]));
+	    }
+	}
+#undef DISP
+#endif
+	return (smb_error);
+}
+
+/********************************************************************
+			OTHER FUNCTIONS
+********************************************************************/
+
+/*
+ * This table describes what interrupts we should ever expect to
+ * see after each ICH command, not including the SMBALERT interrupt.
+ */
+static const u_int8_t ichsmb_state_irqs[] = {
+	/* quick */
+	(ICH_HST_STA_BUS_ERR | ICH_HST_STA_DEV_ERR | ICH_HST_STA_INTR),
+	/* byte */
+	(ICH_HST_STA_BUS_ERR | ICH_HST_STA_DEV_ERR | ICH_HST_STA_INTR),
+	/* byte data */
+	(ICH_HST_STA_BUS_ERR | ICH_HST_STA_DEV_ERR | ICH_HST_STA_INTR),
+	/* word data */
+	(ICH_HST_STA_BUS_ERR | ICH_HST_STA_DEV_ERR | ICH_HST_STA_INTR),
+	/* process call */
+	(ICH_HST_STA_BUS_ERR | ICH_HST_STA_DEV_ERR | ICH_HST_STA_INTR),
+	/* block */
+	(ICH_HST_STA_BUS_ERR | ICH_HST_STA_DEV_ERR | ICH_HST_STA_INTR
+	    | ICH_HST_STA_BYTE_DONE_STS),
+	/* i2c read (not used) */
+	(ICH_HST_STA_BUS_ERR | ICH_HST_STA_DEV_ERR | ICH_HST_STA_INTR
+	    | ICH_HST_STA_BYTE_DONE_STS)
+};
+
+/*
+ * Interrupt handler. This handler is bus-independent. Note that our
+ * interrupt may be shared, so we must handle "false" interrupts.
+ */
+void
+ichsmb_device_intr(void *cookie)
+{
+	const sc_p sc = cookie;
+	const device_t dev = sc->dev;
+	const int maxloops = 16;
+	u_int8_t status;
+	u_int8_t ok_bits;
+	int cmd_index;
+        int count;
+	int s;
+
+	s = splhigh();
+	for (count = 0; count < maxloops; count++) {
+
+		/* Get and reset status bits */
+		status = bus_space_read_1(sc->io_bst, sc->io_bsh, ICH_HST_STA);
+#if ICHSMB_DEBUG
+		if ((status & ~(ICH_HST_STA_INUSE_STS | ICH_HST_STA_HOST_BUSY))
+		    || count > 0) {
+			DBG("%d stat=0x%02x\n", count, status);
+		}
+#endif
+		status &= ~(ICH_HST_STA_INUSE_STS | ICH_HST_STA_HOST_BUSY);
+		if (status == 0)
+			break;
+
+		/* Check for unexpected interrupt */
+		ok_bits = ICH_HST_STA_SMBALERT_STS;
+		cmd_index = sc->ich_cmd >> 2;
+		if (sc->ich_cmd != -1) {
+			KASSERT(cmd_index < sizeof(ichsmb_state_irqs),
+			    ("%s: ich_cmd=%d", device_get_nameunit(dev),
+			    sc->ich_cmd));
+			ok_bits |= ichsmb_state_irqs[cmd_index];
+		}
+		if ((status & ~ok_bits) != 0) {
+			log(LOG_ERR, "%s: irq 0x%02x during %d\n",
+			    device_get_nameunit(dev), status, cmd_index);
+			bus_space_write_1(sc->io_bst, sc->io_bsh,
+			    ICH_HST_STA, (status & ~ok_bits));
+			continue;
+		}
+
+		/* Handle SMBALERT interrupt */
+		if (status & ICH_HST_STA_SMBALERT_STS) {
+			static int smbalert_count = 16;
+			if (smbalert_count > 0) {
+				log(LOG_WARNING, "%s: SMBALERT# rec'd\n",
+				    device_get_nameunit(dev));
+				if (--smbalert_count == 0) {
+					log(LOG_WARNING,
+					    "%s: not logging anymore\n",
+					    device_get_nameunit(dev));
+				}
+			}
+		}
+
+		/* Check for bus error */
+		if (status & ICH_HST_STA_BUS_ERR) {
+			sc->smb_error = SMB_ECOLLI;	/* XXX SMB_EBUSERR? */
+			goto finished;
+		}
+
+		/* Check for device error */
+		if (status & ICH_HST_STA_DEV_ERR) {
+			sc->smb_error = SMB_ENOACK;	/* or SMB_ETIMEOUT? */
+			goto finished;
+		}
+
+		/* Check for byte completion in block transfer */
+		if (status & ICH_HST_STA_BYTE_DONE_STS) {
+			if (sc->block_write) {
+				if (sc->block_index < sc->block_count) {
+
+					/* Write next byte */
+					bus_space_write_1(sc->io_bst,
+					    sc->io_bsh, ICH_BLOCK_DB,
+					    sc->block_data[sc->block_index++]);
+				}
+			} else {
+
+				/* First interrupt, get the count also */
+				if (sc->block_index == 0) {
+					sc->block_count = bus_space_read_1(
+					    sc->io_bst, sc->io_bsh, ICH_D0);
+				}
+
+				/* Get next byte, if any */
+				if (sc->block_index < sc->block_count) {
+
+					/* Read next byte */
+					sc->block_data[sc->block_index++] =
+					    bus_space_read_1(sc->io_bst,
+					      sc->io_bsh, ICH_BLOCK_DB);
+
+					/* Set "LAST_BYTE" bit before reading
+					   the last byte of block data */
+					if (sc->block_index
+					    >= sc->block_count - 1) {
+						bus_space_write_1(sc->io_bst,
+						    sc->io_bsh, ICH_HST_CNT,
+						    ICH_HST_CNT_LAST_BYTE
+							| ICH_HST_CNT_INTREN
+							| sc->ich_cmd);
+					}
+				}
+			}
+		}
+
+		/* Check command completion */
+		if (status & ICH_HST_STA_INTR) {
+			sc->smb_error = SMB_ENOERR;
+finished:
+			sc->ich_cmd = -1;
+			bus_space_write_1(sc->io_bst, sc->io_bsh,
+			    ICH_HST_STA, status);
+			wakeup(sc);
+			break;
+		}
+
+		/* Clear status bits and try again */
+		bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_HST_STA, status);
+	}
+	splx(s);
+
+	/* Too many loops? */
+	if (count == maxloops) {
+		log(LOG_ERR, "%s: interrupt loop, status=0x%02x\n",
+		    device_get_nameunit(dev),
+		    bus_space_read_1(sc->io_bst, sc->io_bsh, ICH_HST_STA));
+	}
+}
+
+/*
+ * Wait for command completion. Assumes splhigh().
+ * Returns an SMB_* error code.
+ */
+static int
+ichsmb_wait(sc_p sc)
+{
+	const device_t dev = sc->dev;
+	int error, smb_error;
+
+	KASSERT(sc->ich_cmd != -1,
+	    ("%s: ich_cmd=%d\n", __FUNCTION__ , sc->ich_cmd));
+sleep:
+	error = tsleep(sc, PZERO | PCATCH, "ichsmb", hz / 4);
+	DBG("tsleep -> %d\n", error);
+	switch (error) {
+	case ERESTART:
+		if (sc->ich_cmd != -1)
+			goto sleep;
+		/* FALLTHROUGH */
+	case 0:
+		smb_error = sc->smb_error;
+		break;
+	case EWOULDBLOCK:
+		log(LOG_ERR, "%s: device timeout, status=0x%02x\n",
+		    device_get_nameunit(dev),
+		    bus_space_read_1(sc->io_bst, sc->io_bsh, ICH_HST_STA));
+		sc->ich_cmd = -1;
+		smb_error = SMB_ETIMEOUT;
+		break;
+	default:
+		smb_error = SMB_EABORT;
+		break;
+	}
+	return (smb_error);
+}
+
+/*
+ * Release resources associated with device.
+ */
+void
+ichsmb_release_resources(sc_p sc)
+{
+	const device_t dev = sc->dev;
+
+	if (sc->irq_handle != NULL) {
+		bus_teardown_intr(dev, sc->irq_res, sc->irq_handle);
+		sc->irq_handle = NULL;
+	}
+	if (sc->irq_res != NULL) {
+		bus_release_resource(dev,
+		    SYS_RES_IRQ, sc->irq_rid, sc->irq_res);
+		sc->irq_res = NULL;
+	}
+	if (sc->io_res != NULL) {
+		bus_release_resource(dev,
+		    SYS_RES_IOPORT, sc->io_rid, sc->io_res);
+		sc->io_res = NULL;
+	}
+}
+