xref: /openbsd/sys/dev/pci/ichiic.c (revision c0d07f7c)
1*c0d07f7cShaesbaert /*	$OpenBSD: ichiic.c,v 1.29 2012/10/05 10:51:28 haesbaert Exp $	*/
23b00bf77Sgrange 
33b00bf77Sgrange /*
4a547cd46Sgrange  * Copyright (c) 2005, 2006 Alexander Yurchenko <grange@openbsd.org>
53b00bf77Sgrange  *
63b00bf77Sgrange  * Permission to use, copy, modify, and distribute this software for any
73b00bf77Sgrange  * purpose with or without fee is hereby granted, provided that the above
83b00bf77Sgrange  * copyright notice and this permission notice appear in all copies.
93b00bf77Sgrange  *
103b00bf77Sgrange  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
113b00bf77Sgrange  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
123b00bf77Sgrange  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
133b00bf77Sgrange  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
143b00bf77Sgrange  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
153b00bf77Sgrange  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
163b00bf77Sgrange  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
173b00bf77Sgrange  */
183b00bf77Sgrange 
193b00bf77Sgrange /*
203b00bf77Sgrange  * Intel ICH SMBus controller driver.
213b00bf77Sgrange  */
223b00bf77Sgrange 
233b00bf77Sgrange #include <sys/param.h>
243b00bf77Sgrange #include <sys/systm.h>
253b00bf77Sgrange #include <sys/device.h>
263b00bf77Sgrange #include <sys/kernel.h>
2773550447Sdlg #include <sys/rwlock.h>
283b00bf77Sgrange 
293b00bf77Sgrange #include <machine/bus.h>
303b00bf77Sgrange 
313b00bf77Sgrange #include <dev/pci/pcidevs.h>
323b00bf77Sgrange #include <dev/pci/pcireg.h>
333b00bf77Sgrange #include <dev/pci/pcivar.h>
343b00bf77Sgrange 
353b00bf77Sgrange #include <dev/pci/ichreg.h>
363b00bf77Sgrange 
373b00bf77Sgrange #include <dev/i2c/i2cvar.h>
383b00bf77Sgrange 
393b00bf77Sgrange #ifdef ICHIIC_DEBUG
403b00bf77Sgrange #define DPRINTF(x) printf x
413b00bf77Sgrange #else
423b00bf77Sgrange #define DPRINTF(x)
433b00bf77Sgrange #endif
443b00bf77Sgrange 
453b00bf77Sgrange #define ICHIIC_DELAY	100
463b00bf77Sgrange #define ICHIIC_TIMEOUT	1
473b00bf77Sgrange 
483b00bf77Sgrange struct ichiic_softc {
493b00bf77Sgrange 	struct device		sc_dev;
503b00bf77Sgrange 
513b00bf77Sgrange 	bus_space_tag_t		sc_iot;
523b00bf77Sgrange 	bus_space_handle_t	sc_ioh;
533b00bf77Sgrange 	void *			sc_ih;
54749dbd03Sgrange 	int			sc_poll;
553b00bf77Sgrange 
563b00bf77Sgrange 	struct i2c_controller	sc_i2c_tag;
5773550447Sdlg 	struct rwlock		sc_i2c_lock;
58c17198b5Sgrange 	struct {
593b00bf77Sgrange 		i2c_op_t     op;
603b00bf77Sgrange 		void *       buf;
613b00bf77Sgrange 		size_t       len;
623b00bf77Sgrange 		int          flags;
63c17198b5Sgrange 		volatile int error;
643b00bf77Sgrange 	}			sc_i2c_xfer;
653b00bf77Sgrange };
663b00bf77Sgrange 
673b00bf77Sgrange int	ichiic_match(struct device *, void *, void *);
683b00bf77Sgrange void	ichiic_attach(struct device *, struct device *, void *);
693b00bf77Sgrange 
703b00bf77Sgrange int	ichiic_i2c_acquire_bus(void *, int);
713b00bf77Sgrange void	ichiic_i2c_release_bus(void *, int);
723b00bf77Sgrange int	ichiic_i2c_exec(void *, i2c_op_t, i2c_addr_t, const void *, size_t,
733b00bf77Sgrange 	    void *, size_t, int);
743b00bf77Sgrange 
753b00bf77Sgrange int	ichiic_intr(void *);
763b00bf77Sgrange 
773b00bf77Sgrange struct cfattach ichiic_ca = {
783b00bf77Sgrange 	sizeof(struct ichiic_softc),
793b00bf77Sgrange 	ichiic_match,
803b00bf77Sgrange 	ichiic_attach
813b00bf77Sgrange };
823b00bf77Sgrange 
833b00bf77Sgrange struct cfdriver ichiic_cd = {
843b00bf77Sgrange 	NULL, "ichiic", DV_DULL
853b00bf77Sgrange };
863b00bf77Sgrange 
873b00bf77Sgrange const struct pci_matchid ichiic_ids[] = {
888e056978Ssthen 	{ PCI_VENDOR_INTEL, PCI_PRODUCT_INTEL_3400_SMB },
89d22bb502Sjsg 	{ PCI_VENDOR_INTEL, PCI_PRODUCT_INTEL_6SERIES_SMB },
909eb33f7aSbrad 	{ PCI_VENDOR_INTEL, PCI_PRODUCT_INTEL_6300ESB_SMB },
91ae7cc0c1Sbrad 	{ PCI_VENDOR_INTEL, PCI_PRODUCT_INTEL_6321ESB_SMB },
92c9849cecSjasper 	{ PCI_VENDOR_INTEL, PCI_PRODUCT_INTEL_7SERIES_SMB },
933b00bf77Sgrange 	{ PCI_VENDOR_INTEL, PCI_PRODUCT_INTEL_82801AA_SMB },
943b00bf77Sgrange 	{ PCI_VENDOR_INTEL, PCI_PRODUCT_INTEL_82801AB_SMB },
953b00bf77Sgrange 	{ PCI_VENDOR_INTEL, PCI_PRODUCT_INTEL_82801BA_SMB },
963b00bf77Sgrange 	{ PCI_VENDOR_INTEL, PCI_PRODUCT_INTEL_82801CA_SMB },
973b00bf77Sgrange 	{ PCI_VENDOR_INTEL, PCI_PRODUCT_INTEL_82801DB_SMB },
989eb33f7aSbrad 	{ PCI_VENDOR_INTEL, PCI_PRODUCT_INTEL_82801E_SMB },
993b00bf77Sgrange 	{ PCI_VENDOR_INTEL, PCI_PRODUCT_INTEL_82801EB_SMB },
1003b00bf77Sgrange 	{ PCI_VENDOR_INTEL, PCI_PRODUCT_INTEL_82801FB_SMB },
101e182382cSbrad 	{ PCI_VENDOR_INTEL, PCI_PRODUCT_INTEL_82801GB_SMB },
102a2cd58f7Sbrad 	{ PCI_VENDOR_INTEL, PCI_PRODUCT_INTEL_82801H_SMB },
103a54030c0Sbrad 	{ PCI_VENDOR_INTEL, PCI_PRODUCT_INTEL_82801I_SMB },
1048e056978Ssthen 	{ PCI_VENDOR_INTEL, PCI_PRODUCT_INTEL_82801JD_SMB },
10554d12d52Sjsg 	{ PCI_VENDOR_INTEL, PCI_PRODUCT_INTEL_82801JI_SMB },
10654d12d52Sjsg 	{ PCI_VENDOR_INTEL, PCI_PRODUCT_INTEL_C600_SMB }
1073b00bf77Sgrange };
1083b00bf77Sgrange 
1093b00bf77Sgrange int
1103b00bf77Sgrange ichiic_match(struct device *parent, void *match, void *aux)
1113b00bf77Sgrange {
1123b00bf77Sgrange 	return (pci_matchbyid(aux, ichiic_ids,
1133b00bf77Sgrange 	    sizeof(ichiic_ids) / sizeof(ichiic_ids[0])));
1143b00bf77Sgrange }
1153b00bf77Sgrange 
1163b00bf77Sgrange void
1173b00bf77Sgrange ichiic_attach(struct device *parent, struct device *self, void *aux)
1183b00bf77Sgrange {
1193b00bf77Sgrange 	struct ichiic_softc *sc = (struct ichiic_softc *)self;
1203b00bf77Sgrange 	struct pci_attach_args *pa = aux;
1213b00bf77Sgrange 	struct i2cbus_attach_args iba;
122749dbd03Sgrange 	pcireg_t conf;
1233b00bf77Sgrange 	bus_size_t iosize;
1243b00bf77Sgrange 	pci_intr_handle_t ih;
1253b00bf77Sgrange 	const char *intrstr = NULL;
1263b00bf77Sgrange 
127d204c798Sgrange 	/* Read configuration */
128d204c798Sgrange 	conf = pci_conf_read(pa->pa_pc, pa->pa_tag, ICH_SMB_HOSTC);
1296f23e57aSgrange 	DPRINTF((": conf 0x%08x", conf));
130d204c798Sgrange 
131d204c798Sgrange 	if ((conf & ICH_SMB_HOSTC_HSTEN) == 0) {
132d204c798Sgrange 		printf(": SMBus disabled\n");
133d204c798Sgrange 		return;
134d204c798Sgrange 	}
135d204c798Sgrange 
1363b00bf77Sgrange 	/* Map I/O space */
1373b00bf77Sgrange 	if (pci_mapreg_map(pa, ICH_SMB_BASE, PCI_MAPREG_TYPE_IO, 0,
1383b00bf77Sgrange 	    &sc->sc_iot, &sc->sc_ioh, NULL, &iosize, 0)) {
139e10c952fSsthen 		printf(": can't map i/o space\n");
1403b00bf77Sgrange 		return;
1413b00bf77Sgrange 	}
1423b00bf77Sgrange 
143749dbd03Sgrange 	sc->sc_poll = 1;
144e3269dfcSgrange 	if (conf & ICH_SMB_HOSTC_SMIEN) {
145e3269dfcSgrange 		/* No PCI IRQ */
146e3269dfcSgrange 		printf(": SMI");
147749dbd03Sgrange 	} else {
1483b00bf77Sgrange 		/* Install interrupt handler */
149e3269dfcSgrange 		if (pci_intr_map(pa, &ih) == 0) {
1503b00bf77Sgrange 			intrstr = pci_intr_string(pa->pa_pc, ih);
151749dbd03Sgrange 			sc->sc_ih = pci_intr_establish(pa->pa_pc, ih, IPL_BIO,
152749dbd03Sgrange 			    ichiic_intr, sc, sc->sc_dev.dv_xname);
153e3269dfcSgrange 			if (sc->sc_ih != NULL) {
1543b00bf77Sgrange 				printf(": %s", intrstr);
155e3269dfcSgrange 				sc->sc_poll = 0;
156e3269dfcSgrange 			}
157e3269dfcSgrange 		}
158e3269dfcSgrange 		if (sc->sc_poll)
159e3269dfcSgrange 			printf(": polling");
160749dbd03Sgrange 	}
1613b00bf77Sgrange 
1623b00bf77Sgrange 	printf("\n");
1633b00bf77Sgrange 
1643b00bf77Sgrange 	/* Attach I2C bus */
16573550447Sdlg 	rw_init(&sc->sc_i2c_lock, "iiclk");
1663b00bf77Sgrange 	sc->sc_i2c_tag.ic_cookie = sc;
1673b00bf77Sgrange 	sc->sc_i2c_tag.ic_acquire_bus = ichiic_i2c_acquire_bus;
1683b00bf77Sgrange 	sc->sc_i2c_tag.ic_release_bus = ichiic_i2c_release_bus;
1693b00bf77Sgrange 	sc->sc_i2c_tag.ic_exec = ichiic_i2c_exec;
170a5a63700Sderaadt 
171f57d9f10Sgrange 	bzero(&iba, sizeof(iba));
1723b00bf77Sgrange 	iba.iba_name = "iic";
1733b00bf77Sgrange 	iba.iba_tag = &sc->sc_i2c_tag;
1743b00bf77Sgrange 	config_found(self, &iba, iicbus_print);
1753b00bf77Sgrange 
1763b00bf77Sgrange 	return;
1773b00bf77Sgrange }
1783b00bf77Sgrange 
1793b00bf77Sgrange int
1803b00bf77Sgrange ichiic_i2c_acquire_bus(void *cookie, int flags)
1813b00bf77Sgrange {
1823b00bf77Sgrange 	struct ichiic_softc *sc = cookie;
1833b00bf77Sgrange 
1847ecfa26eSgrange 	if (cold || sc->sc_poll || (flags & I2C_F_POLL))
1853b00bf77Sgrange 		return (0);
1863b00bf77Sgrange 
18773550447Sdlg 	return (rw_enter(&sc->sc_i2c_lock, RW_WRITE | RW_INTR));
1883b00bf77Sgrange }
1893b00bf77Sgrange 
1903b00bf77Sgrange void
1913b00bf77Sgrange ichiic_i2c_release_bus(void *cookie, int flags)
1923b00bf77Sgrange {
1933b00bf77Sgrange 	struct ichiic_softc *sc = cookie;
1943b00bf77Sgrange 
1957ecfa26eSgrange 	if (cold || sc->sc_poll || (flags & I2C_F_POLL))
1963b00bf77Sgrange 		return;
1973b00bf77Sgrange 
19873550447Sdlg 	rw_exit(&sc->sc_i2c_lock);
1993b00bf77Sgrange }
2003b00bf77Sgrange 
2013b00bf77Sgrange int
2023b00bf77Sgrange ichiic_i2c_exec(void *cookie, i2c_op_t op, i2c_addr_t addr,
2033b00bf77Sgrange     const void *cmdbuf, size_t cmdlen, void *buf, size_t len, int flags)
2043b00bf77Sgrange {
2053b00bf77Sgrange 	struct ichiic_softc *sc = cookie;
2063b00bf77Sgrange 	u_int8_t *b;
2073b00bf77Sgrange 	u_int8_t ctl, st;
2083b00bf77Sgrange 	int retries;
2093b00bf77Sgrange 
2106f23e57aSgrange 	DPRINTF(("%s: exec: op %d, addr 0x%02x, cmdlen %d, len %d, "
2116f23e57aSgrange 	    "flags 0x%02x\n", sc->sc_dev.dv_xname, op, addr, cmdlen,
2126f23e57aSgrange 	    len, flags));
213d204c798Sgrange 
214c90a9223Sgrange 	/* Wait for bus to be idle */
215c90a9223Sgrange 	for (retries = 100; retries > 0; retries--) {
216d204c798Sgrange 		st = bus_space_read_1(sc->sc_iot, sc->sc_ioh, ICH_SMB_HS);
217c90a9223Sgrange 		if (!(st & ICH_SMB_HS_BUSY))
218c90a9223Sgrange 			break;
219c90a9223Sgrange 		DELAY(ICHIIC_DELAY);
220c90a9223Sgrange 	}
221d204c798Sgrange 	DPRINTF(("%s: exec: st 0x%b\n", sc->sc_dev.dv_xname, st,
222d204c798Sgrange 	    ICH_SMB_HS_BITS));
223d204c798Sgrange 	if (st & ICH_SMB_HS_BUSY)
224c5eaf0b6Sgrange 		return (1);
225749dbd03Sgrange 
2267ecfa26eSgrange 	if (cold || sc->sc_poll)
227749dbd03Sgrange 		flags |= I2C_F_POLL;
2283b00bf77Sgrange 
2293b00bf77Sgrange 	if (!I2C_OP_STOP_P(op) || cmdlen > 1 || len > 2)
230c5eaf0b6Sgrange 		return (1);
2313b00bf77Sgrange 
2323b00bf77Sgrange 	/* Setup transfer */
2333b00bf77Sgrange 	sc->sc_i2c_xfer.op = op;
2343b00bf77Sgrange 	sc->sc_i2c_xfer.buf = buf;
2353b00bf77Sgrange 	sc->sc_i2c_xfer.len = len;
2363b00bf77Sgrange 	sc->sc_i2c_xfer.flags = flags;
2373b00bf77Sgrange 	sc->sc_i2c_xfer.error = 0;
2383b00bf77Sgrange 
2393b00bf77Sgrange 	/* Set slave address and transfer direction */
2403b00bf77Sgrange 	bus_space_write_1(sc->sc_iot, sc->sc_ioh, ICH_SMB_TXSLVA,
2413b00bf77Sgrange 	    ICH_SMB_TXSLVA_ADDR(addr) |
2423b00bf77Sgrange 	    (I2C_OP_READ_P(op) ? ICH_SMB_TXSLVA_READ : 0));
2433b00bf77Sgrange 
2443b00bf77Sgrange 	b = (void *)cmdbuf;
2453b00bf77Sgrange 	if (cmdlen > 0)
2463b00bf77Sgrange 		/* Set command byte */
2473b00bf77Sgrange 		bus_space_write_1(sc->sc_iot, sc->sc_ioh, ICH_SMB_HCMD, b[0]);
2483b00bf77Sgrange 
2493b00bf77Sgrange 	if (I2C_OP_WRITE_P(op)) {
2503b00bf77Sgrange 		/* Write data */
2513b00bf77Sgrange 		b = buf;
2523b00bf77Sgrange 		if (len > 0)
2533b00bf77Sgrange 			bus_space_write_1(sc->sc_iot, sc->sc_ioh,
2543b00bf77Sgrange 			    ICH_SMB_HD0, b[0]);
2553b00bf77Sgrange 		if (len > 1)
2563b00bf77Sgrange 			bus_space_write_1(sc->sc_iot, sc->sc_ioh,
2573b00bf77Sgrange 			    ICH_SMB_HD1, b[1]);
2583b00bf77Sgrange 	}
2593b00bf77Sgrange 
2603b00bf77Sgrange 	/* Set SMBus command */
2613b00bf77Sgrange 	if (len == 0)
2623b00bf77Sgrange 		ctl = ICH_SMB_HC_CMD_BYTE;
2633b00bf77Sgrange 	else if (len == 1)
2643b00bf77Sgrange 		ctl = ICH_SMB_HC_CMD_BDATA;
2653b00bf77Sgrange 	else if (len == 2)
2663b00bf77Sgrange 		ctl = ICH_SMB_HC_CMD_WDATA;
267*c0d07f7cShaesbaert 	else
268*c0d07f7cShaesbaert 		panic("%s: unexpected len %zd", __func__, len);
2693b00bf77Sgrange 
2703b00bf77Sgrange 	if ((flags & I2C_F_POLL) == 0)
2713b00bf77Sgrange 		ctl |= ICH_SMB_HC_INTREN;
2723b00bf77Sgrange 
2733b00bf77Sgrange 	/* Start transaction */
2743b00bf77Sgrange 	ctl |= ICH_SMB_HC_START;
2753b00bf77Sgrange 	bus_space_write_1(sc->sc_iot, sc->sc_ioh, ICH_SMB_HC, ctl);
2763b00bf77Sgrange 
2773b00bf77Sgrange 	if (flags & I2C_F_POLL) {
2783b00bf77Sgrange 		/* Poll for completion */
2793b00bf77Sgrange 		DELAY(ICHIIC_DELAY);
2803b00bf77Sgrange 		for (retries = 1000; retries > 0; retries--) {
2813b00bf77Sgrange 			st = bus_space_read_1(sc->sc_iot, sc->sc_ioh,
2823b00bf77Sgrange 			    ICH_SMB_HS);
2833b00bf77Sgrange 			if ((st & ICH_SMB_HS_BUSY) == 0)
2843b00bf77Sgrange 				break;
2853b00bf77Sgrange 			DELAY(ICHIIC_DELAY);
2863b00bf77Sgrange 		}
287d204c798Sgrange 		if (st & ICH_SMB_HS_BUSY)
288d204c798Sgrange 			goto timeout;
2893b00bf77Sgrange 		ichiic_intr(sc);
2903b00bf77Sgrange 	} else {
291c17198b5Sgrange 		/* Wait for interrupt */
292cda39e48Sderaadt 		if (tsleep(sc, PRIBIO, "ichiic", ICHIIC_TIMEOUT * hz))
293d204c798Sgrange 			goto timeout;
2943b00bf77Sgrange 	}
2953b00bf77Sgrange 
2963b00bf77Sgrange 	if (sc->sc_i2c_xfer.error)
2973b00bf77Sgrange 		return (1);
2983b00bf77Sgrange 
2993b00bf77Sgrange 	return (0);
300d204c798Sgrange 
301d204c798Sgrange timeout:
302d204c798Sgrange 	/*
303d204c798Sgrange 	 * Transfer timeout. Kill the transaction and clear status bits.
304d204c798Sgrange 	 */
305d204c798Sgrange 	bus_space_write_1(sc->sc_iot, sc->sc_ioh, ICH_SMB_HC,
306d204c798Sgrange 	    ICH_SMB_HC_KILL);
307d204c798Sgrange 	DELAY(ICHIIC_DELAY);
308d204c798Sgrange 	st = bus_space_read_1(sc->sc_iot, sc->sc_ioh, ICH_SMB_HS);
309d204c798Sgrange 	if ((st & ICH_SMB_HS_FAILED) == 0)
3106f23e57aSgrange 		printf("%s: abort failed, status 0x%b\n",
311d204c798Sgrange 		    sc->sc_dev.dv_xname, st, ICH_SMB_HS_BITS);
312d204c798Sgrange 	bus_space_write_1(sc->sc_iot, sc->sc_ioh, ICH_SMB_HS, st);
313d204c798Sgrange 	return (1);
3143b00bf77Sgrange }
3153b00bf77Sgrange 
3163b00bf77Sgrange int
3173b00bf77Sgrange ichiic_intr(void *arg)
3183b00bf77Sgrange {
3193b00bf77Sgrange 	struct ichiic_softc *sc = arg;
3203b00bf77Sgrange 	u_int8_t st;
3213b00bf77Sgrange 	u_int8_t *b;
3223b00bf77Sgrange 	size_t len;
3233b00bf77Sgrange 
3243b00bf77Sgrange 	/* Read status */
3253b00bf77Sgrange 	st = bus_space_read_1(sc->sc_iot, sc->sc_ioh, ICH_SMB_HS);
3263b00bf77Sgrange 	if ((st & ICH_SMB_HS_BUSY) != 0 || (st & (ICH_SMB_HS_INTR |
3273b00bf77Sgrange 	    ICH_SMB_HS_DEVERR | ICH_SMB_HS_BUSERR | ICH_SMB_HS_FAILED |
3283b00bf77Sgrange 	    ICH_SMB_HS_SMBAL | ICH_SMB_HS_BDONE)) == 0)
3293b00bf77Sgrange 		/* Interrupt was not for us */
3303b00bf77Sgrange 		return (0);
3313b00bf77Sgrange 
3323b00bf77Sgrange 	DPRINTF(("%s: intr st 0x%b\n", sc->sc_dev.dv_xname, st,
3333b00bf77Sgrange 	    ICH_SMB_HS_BITS));
3343b00bf77Sgrange 
3353b00bf77Sgrange 	/* Clear status bits */
3363b00bf77Sgrange 	bus_space_write_1(sc->sc_iot, sc->sc_ioh, ICH_SMB_HS, st);
3373b00bf77Sgrange 
3383b00bf77Sgrange 	/* Check for errors */
3393b00bf77Sgrange 	if (st & (ICH_SMB_HS_DEVERR | ICH_SMB_HS_BUSERR | ICH_SMB_HS_FAILED)) {
3403b00bf77Sgrange 		sc->sc_i2c_xfer.error = 1;
3413b00bf77Sgrange 		goto done;
3423b00bf77Sgrange 	}
3433b00bf77Sgrange 
3443b00bf77Sgrange 	if (st & ICH_SMB_HS_INTR) {
3453b00bf77Sgrange 		if (I2C_OP_WRITE_P(sc->sc_i2c_xfer.op))
3463b00bf77Sgrange 			goto done;
3473b00bf77Sgrange 
3483b00bf77Sgrange 		/* Read data */
3493b00bf77Sgrange 		b = sc->sc_i2c_xfer.buf;
3503b00bf77Sgrange 		len = sc->sc_i2c_xfer.len;
3513b00bf77Sgrange 		if (len > 0)
3523b00bf77Sgrange 			b[0] = bus_space_read_1(sc->sc_iot, sc->sc_ioh,
3533b00bf77Sgrange 			    ICH_SMB_HD0);
3543b00bf77Sgrange 		if (len > 1)
3553b00bf77Sgrange 			b[1] = bus_space_read_1(sc->sc_iot, sc->sc_ioh,
3563b00bf77Sgrange 			    ICH_SMB_HD1);
3573b00bf77Sgrange 	}
3583b00bf77Sgrange 
3593b00bf77Sgrange done:
3603b00bf77Sgrange 	if ((sc->sc_i2c_xfer.flags & I2C_F_POLL) == 0)
3613b00bf77Sgrange 		wakeup(sc);
3623b00bf77Sgrange 	return (1);
3633b00bf77Sgrange }
364