xref: /freebsd/sys/dev/ichsmb/ichsmb.c (revision 87569f75a91f298c52a71823c04d41cf53c88889)
1 /*-
2  * ichsmb.c
3  *
4  * Author: Archie Cobbs <archie@freebsd.org>
5  * Copyright (c) 2000 Whistle Communications, Inc.
6  * All rights reserved.
7  *
8  * Subject to the following obligations and disclaimer of warranty, use and
9  * redistribution of this software, in source or object code forms, with or
10  * without modifications are expressly permitted by Whistle Communications;
11  * provided, however, that:
12  * 1. Any and all reproductions of the source or object code must include the
13  *    copyright notice above and the following disclaimer of warranties; and
14  * 2. No rights are granted, in any manner or form, to use Whistle
15  *    Communications, Inc. trademarks, including the mark "WHISTLE
16  *    COMMUNICATIONS" on advertising, endorsements, or otherwise except as
17  *    such appears in the above copyright notice or in the software.
18  *
19  * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
20  * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
21  * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
22  * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
23  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
24  * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
25  * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
26  * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
27  * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
28  * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
29  * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
30  * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
31  * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
32  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
33  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
34  * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
35  * OF SUCH DAMAGE.
36  */
37 
38 #include <sys/cdefs.h>
39 __FBSDID("$FreeBSD$");
40 
41 /*
42  * Support for the SMBus controller logical device which is part of the
43  * Intel 81801AA (ICH) and 81801AB (ICH0) I/O controller hub chips.
44  *
45  * This driver assumes that the generic SMBus code will ensure that
46  * at most one process at a time calls into the SMBus methods below.
47  */
48 
49 #include <sys/param.h>
50 #include <sys/systm.h>
51 #include <sys/kernel.h>
52 #include <sys/errno.h>
53 #include <sys/lock.h>
54 #include <sys/mutex.h>
55 #include <sys/syslog.h>
56 #include <sys/bus.h>
57 
58 #include <machine/bus.h>
59 #include <sys/rman.h>
60 #include <machine/resource.h>
61 
62 #include <dev/smbus/smbconf.h>
63 
64 #include <dev/ichsmb/ichsmb_var.h>
65 #include <dev/ichsmb/ichsmb_reg.h>
66 
67 /*
68  * Enable debugging by defining ICHSMB_DEBUG to a non-zero value.
69  */
70 #define ICHSMB_DEBUG	0
71 #if ICHSMB_DEBUG != 0 && defined(__CC_SUPPORTS___FUNC__)
72 #define DBG(fmt, args...)	\
73 	do { log(LOG_DEBUG, "%s: " fmt, __func__ , ## args); } while (0)
74 #else
75 #define DBG(fmt, args...)	do { } while (0)
76 #endif
77 
78 /*
79  * Our child device driver name
80  */
81 #define DRIVER_SMBUS	"smbus"
82 
83 /*
84  * Internal functions
85  */
86 static int ichsmb_wait(sc_p sc);
87 
88 /********************************************************************
89 		BUS-INDEPENDENT BUS METHODS
90 ********************************************************************/
91 
92 /*
93  * Handle probe-time duties that are independent of the bus
94  * our device lives on.
95  */
96 int
97 ichsmb_probe(device_t dev)
98 {
99 	return (BUS_PROBE_DEFAULT);
100 }
101 
102 /*
103  * Handle attach-time duties that are independent of the bus
104  * our device lives on.
105  */
106 int
107 ichsmb_attach(device_t dev)
108 {
109 	const sc_p sc = device_get_softc(dev);
110 	int error;
111 
112 	/* Add child: an instance of the "smbus" device */
113 	if ((sc->smb = device_add_child(dev, DRIVER_SMBUS, -1)) == NULL) {
114 		log(LOG_ERR, "%s: no \"%s\" child found\n",
115 		    device_get_nameunit(dev), DRIVER_SMBUS);
116 		return (ENXIO);
117 	}
118 
119 	/* Clear interrupt conditions */
120 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_HST_STA, 0xff);
121 
122 	/* Add "smbus" child */
123 	if ((error = bus_generic_attach(dev)) != 0) {
124 		log(LOG_ERR, "%s: failed to attach child: %d\n",
125 		    device_get_nameunit(dev), error);
126 		return (ENXIO);
127 	}
128 
129 	/* Create mutex */
130 	mtx_init(&sc->mutex, device_get_nameunit(dev), "ichsmb", MTX_DEF);
131 	return (0);
132 }
133 
134 /********************************************************************
135 			SMBUS METHODS
136 ********************************************************************/
137 
138 int
139 ichsmb_callback(device_t dev, int index, caddr_t data)
140 {
141 	int smb_error = 0;
142 
143 	DBG("index=%d how=%d\n", index, data ? *(int *)data : -1);
144 	switch (index) {
145 	case SMB_REQUEST_BUS:
146 		break;
147 	case SMB_RELEASE_BUS:
148 		break;
149 	default:
150 		smb_error = SMB_EABORT;	/* XXX */
151 		break;
152 	}
153 	DBG("smb_error=%d\n", smb_error);
154 	return (smb_error);
155 }
156 
157 int
158 ichsmb_quick(device_t dev, u_char slave, int how)
159 {
160 	const sc_p sc = device_get_softc(dev);
161 	int smb_error;
162 
163 	DBG("slave=0x%02x how=%d\n", slave, how);
164 	KASSERT(sc->ich_cmd == -1,
165 	    ("%s: ich_cmd=%d\n", __func__ , sc->ich_cmd));
166 	switch (how) {
167 	case SMB_QREAD:
168 	case SMB_QWRITE:
169 		mtx_lock(&sc->mutex);
170 		sc->ich_cmd = ICH_HST_CNT_SMB_CMD_QUICK;
171 		bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_XMIT_SLVA,
172 		    (slave << 1) | (how == SMB_QREAD ?
173 	    		ICH_XMIT_SLVA_READ : ICH_XMIT_SLVA_WRITE));
174 		bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_HST_CNT,
175 		    ICH_HST_CNT_START | ICH_HST_CNT_INTREN | sc->ich_cmd);
176 		smb_error = ichsmb_wait(sc);
177 		mtx_unlock(&sc->mutex);
178 		break;
179 	default:
180 		smb_error = SMB_ENOTSUPP;
181 	}
182 	DBG("smb_error=%d\n", smb_error);
183 	return (smb_error);
184 }
185 
186 int
187 ichsmb_sendb(device_t dev, u_char slave, char byte)
188 {
189 	const sc_p sc = device_get_softc(dev);
190 	int smb_error;
191 
192 	DBG("slave=0x%02x byte=0x%02x\n", slave, (u_char)byte);
193 	KASSERT(sc->ich_cmd == -1,
194 	    ("%s: ich_cmd=%d\n", __func__ , sc->ich_cmd));
195 	mtx_lock(&sc->mutex);
196 	sc->ich_cmd = ICH_HST_CNT_SMB_CMD_BYTE;
197 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_XMIT_SLVA,
198 	    (slave << 1) | ICH_XMIT_SLVA_WRITE);
199 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_HST_CMD, byte);
200 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_HST_CNT,
201 	    ICH_HST_CNT_START | ICH_HST_CNT_INTREN | sc->ich_cmd);
202 	smb_error = ichsmb_wait(sc);
203 	mtx_unlock(&sc->mutex);
204 	DBG("smb_error=%d\n", smb_error);
205 	return (smb_error);
206 }
207 
208 int
209 ichsmb_recvb(device_t dev, u_char slave, char *byte)
210 {
211 	const sc_p sc = device_get_softc(dev);
212 	int smb_error;
213 
214 	DBG("slave=0x%02x\n", slave);
215 	KASSERT(sc->ich_cmd == -1,
216 	    ("%s: ich_cmd=%d\n", __func__ , sc->ich_cmd));
217 	mtx_lock(&sc->mutex);
218 	sc->ich_cmd = ICH_HST_CNT_SMB_CMD_BYTE;
219 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_XMIT_SLVA,
220 	    (slave << 1) | ICH_XMIT_SLVA_READ);
221 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_HST_CNT,
222 	    ICH_HST_CNT_START | ICH_HST_CNT_INTREN | sc->ich_cmd);
223 	if ((smb_error = ichsmb_wait(sc)) == SMB_ENOERR)
224 		*byte = bus_space_read_1(sc->io_bst, sc->io_bsh, ICH_D0);
225 	mtx_unlock(&sc->mutex);
226 	DBG("smb_error=%d byte=0x%02x\n", smb_error, (u_char)*byte);
227 	return (smb_error);
228 }
229 
230 int
231 ichsmb_writeb(device_t dev, u_char slave, char cmd, char byte)
232 {
233 	const sc_p sc = device_get_softc(dev);
234 	int smb_error;
235 
236 	DBG("slave=0x%02x cmd=0x%02x byte=0x%02x\n",
237 	    slave, (u_char)cmd, (u_char)byte);
238 	KASSERT(sc->ich_cmd == -1,
239 	    ("%s: ich_cmd=%d\n", __func__ , sc->ich_cmd));
240 	mtx_lock(&sc->mutex);
241 	sc->ich_cmd = ICH_HST_CNT_SMB_CMD_BYTE_DATA;
242 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_XMIT_SLVA,
243 	    (slave << 1) | ICH_XMIT_SLVA_WRITE);
244 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_HST_CMD, cmd);
245 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_D0, byte);
246 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_HST_CNT,
247 	    ICH_HST_CNT_START | ICH_HST_CNT_INTREN | sc->ich_cmd);
248 	smb_error = ichsmb_wait(sc);
249 	mtx_unlock(&sc->mutex);
250 	DBG("smb_error=%d\n", smb_error);
251 	return (smb_error);
252 }
253 
254 int
255 ichsmb_writew(device_t dev, u_char slave, char cmd, short word)
256 {
257 	const sc_p sc = device_get_softc(dev);
258 	int smb_error;
259 
260 	DBG("slave=0x%02x cmd=0x%02x word=0x%04x\n",
261 	    slave, (u_char)cmd, (u_int16_t)word);
262 	KASSERT(sc->ich_cmd == -1,
263 	    ("%s: ich_cmd=%d\n", __func__ , sc->ich_cmd));
264 	mtx_lock(&sc->mutex);
265 	sc->ich_cmd = ICH_HST_CNT_SMB_CMD_WORD_DATA;
266 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_XMIT_SLVA,
267 	    (slave << 1) | ICH_XMIT_SLVA_WRITE);
268 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_HST_CMD, cmd);
269 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_D0, word & 0xff);
270 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_D1, word >> 8);
271 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_HST_CNT,
272 	    ICH_HST_CNT_START | ICH_HST_CNT_INTREN | sc->ich_cmd);
273 	smb_error = ichsmb_wait(sc);
274 	mtx_unlock(&sc->mutex);
275 	DBG("smb_error=%d\n", smb_error);
276 	return (smb_error);
277 }
278 
279 int
280 ichsmb_readb(device_t dev, u_char slave, char cmd, char *byte)
281 {
282 	const sc_p sc = device_get_softc(dev);
283 	int smb_error;
284 
285 	DBG("slave=0x%02x cmd=0x%02x\n", slave, (u_char)cmd);
286 	KASSERT(sc->ich_cmd == -1,
287 	    ("%s: ich_cmd=%d\n", __func__ , sc->ich_cmd));
288 	mtx_lock(&sc->mutex);
289 	sc->ich_cmd = ICH_HST_CNT_SMB_CMD_BYTE_DATA;
290 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_XMIT_SLVA,
291 	    (slave << 1) | ICH_XMIT_SLVA_READ);
292 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_HST_CMD, cmd);
293 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_HST_CNT,
294 	    ICH_HST_CNT_START | ICH_HST_CNT_INTREN | sc->ich_cmd);
295 	if ((smb_error = ichsmb_wait(sc)) == SMB_ENOERR)
296 		*byte = bus_space_read_1(sc->io_bst, sc->io_bsh, ICH_D0);
297 	mtx_unlock(&sc->mutex);
298 	DBG("smb_error=%d byte=0x%02x\n", smb_error, (u_char)*byte);
299 	return (smb_error);
300 }
301 
302 int
303 ichsmb_readw(device_t dev, u_char slave, char cmd, short *word)
304 {
305 	const sc_p sc = device_get_softc(dev);
306 	int smb_error;
307 
308 	DBG("slave=0x%02x cmd=0x%02x\n", slave, (u_char)cmd);
309 	KASSERT(sc->ich_cmd == -1,
310 	    ("%s: ich_cmd=%d\n", __func__ , sc->ich_cmd));
311 	mtx_lock(&sc->mutex);
312 	sc->ich_cmd = ICH_HST_CNT_SMB_CMD_WORD_DATA;
313 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_XMIT_SLVA,
314 	    (slave << 1) | ICH_XMIT_SLVA_READ);
315 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_HST_CMD, cmd);
316 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_HST_CNT,
317 	    ICH_HST_CNT_START | ICH_HST_CNT_INTREN | sc->ich_cmd);
318 	if ((smb_error = ichsmb_wait(sc)) == SMB_ENOERR) {
319 		*word = (bus_space_read_1(sc->io_bst,
320 			sc->io_bsh, ICH_D0) & 0xff)
321 		  | (bus_space_read_1(sc->io_bst,
322 			sc->io_bsh, ICH_D1) << 8);
323 	}
324 	mtx_unlock(&sc->mutex);
325 	DBG("smb_error=%d word=0x%04x\n", smb_error, (u_int16_t)*word);
326 	return (smb_error);
327 }
328 
329 int
330 ichsmb_pcall(device_t dev, u_char slave, char cmd, short sdata, short *rdata)
331 {
332 	const sc_p sc = device_get_softc(dev);
333 	int smb_error;
334 
335 	DBG("slave=0x%02x cmd=0x%02x sdata=0x%04x\n",
336 	    slave, (u_char)cmd, (u_int16_t)sdata);
337 	KASSERT(sc->ich_cmd == -1,
338 	    ("%s: ich_cmd=%d\n", __func__ , sc->ich_cmd));
339 	mtx_lock(&sc->mutex);
340 	sc->ich_cmd = ICH_HST_CNT_SMB_CMD_PROC_CALL;
341 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_XMIT_SLVA,
342 	    (slave << 1) | ICH_XMIT_SLVA_WRITE);
343 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_HST_CMD, cmd);
344 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_D0, sdata & 0xff);
345 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_D1, sdata >> 8);
346 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_HST_CNT,
347 	    ICH_HST_CNT_START | ICH_HST_CNT_INTREN | sc->ich_cmd);
348 	if ((smb_error = ichsmb_wait(sc)) == SMB_ENOERR) {
349 		*rdata = (bus_space_read_1(sc->io_bst,
350 			sc->io_bsh, ICH_D0) & 0xff)
351 		  | (bus_space_read_1(sc->io_bst,
352 			sc->io_bsh, ICH_D1) << 8);
353 	}
354 	mtx_unlock(&sc->mutex);
355 	DBG("smb_error=%d rdata=0x%04x\n", smb_error, (u_int16_t)*rdata);
356 	return (smb_error);
357 }
358 
359 int
360 ichsmb_bwrite(device_t dev, u_char slave, char cmd, u_char count, char *buf)
361 {
362 	const sc_p sc = device_get_softc(dev);
363 	int smb_error;
364 
365 	DBG("slave=0x%02x cmd=0x%02x count=%d\n", slave, (u_char)cmd, count);
366 #if ICHSMB_DEBUG
367 #define DISP(ch)	(((ch) < 0x20 || (ch) >= 0x7e) ? '.' : (ch))
368 	{
369 	    u_char *p;
370 
371 	    for (p = (u_char *)buf; p - (u_char *)buf < 32; p += 8) {
372 		DBG("%02x: %02x %02x %02x %02x %02x %02x %02x %02x"
373 		    "  %c%c%c%c%c%c%c%c", (p - (u_char *)buf),
374 		    p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7],
375 		    DISP(p[0]), DISP(p[1]), DISP(p[2]), DISP(p[3]),
376 		    DISP(p[4]), DISP(p[5]), DISP(p[6]), DISP(p[7]));
377 	    }
378 	}
379 #undef DISP
380 #endif
381 	KASSERT(sc->ich_cmd == -1,
382 	    ("%s: ich_cmd=%d\n", __func__ , sc->ich_cmd));
383 	if (count < 1 || count > 32)
384 		return (EINVAL);
385 	bcopy(buf, sc->block_data, count);
386 	sc->block_count = count;
387 	sc->block_index = 1;
388 	sc->block_write = 1;
389 
390 	mtx_lock(&sc->mutex);
391 	sc->ich_cmd = ICH_HST_CNT_SMB_CMD_BLOCK;
392 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_XMIT_SLVA,
393 	    (slave << 1) | ICH_XMIT_SLVA_WRITE);
394 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_HST_CMD, cmd);
395 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_D0, count);
396 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_BLOCK_DB, buf[0]);
397 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_HST_CNT,
398 	    ICH_HST_CNT_START | ICH_HST_CNT_INTREN | sc->ich_cmd);
399 	smb_error = ichsmb_wait(sc);
400 	mtx_unlock(&sc->mutex);
401 	DBG("smb_error=%d\n", smb_error);
402 	return (smb_error);
403 }
404 
405 int
406 ichsmb_bread(device_t dev, u_char slave, char cmd, u_char count, char *buf)
407 {
408 	const sc_p sc = device_get_softc(dev);
409 	int smb_error;
410 
411 	DBG("slave=0x%02x cmd=0x%02x count=%d\n", slave, (u_char)cmd, count);
412 	KASSERT(sc->ich_cmd == -1,
413 	    ("%s: ich_cmd=%d\n", __func__ , sc->ich_cmd));
414 	if (count < 1 || count > 32)
415 		return (EINVAL);
416 	bzero(sc->block_data, sizeof(sc->block_data));
417 	sc->block_count = count;
418 	sc->block_index = 0;
419 	sc->block_write = 0;
420 
421 	mtx_lock(&sc->mutex);
422 	sc->ich_cmd = ICH_HST_CNT_SMB_CMD_BLOCK;
423 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_XMIT_SLVA,
424 	    (slave << 1) | ICH_XMIT_SLVA_READ);
425 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_HST_CMD, cmd);
426 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_D0, count); /* XXX? */
427 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_HST_CNT,
428 	    ICH_HST_CNT_START | ICH_HST_CNT_INTREN | sc->ich_cmd);
429 	if ((smb_error = ichsmb_wait(sc)) == SMB_ENOERR)
430 		bcopy(sc->block_data, buf, sc->block_count);
431 	mtx_unlock(&sc->mutex);
432 	DBG("smb_error=%d\n", smb_error);
433 #if ICHSMB_DEBUG
434 #define DISP(ch)	(((ch) < 0x20 || (ch) >= 0x7e) ? '.' : (ch))
435 	{
436 	    u_char *p;
437 
438 	    for (p = (u_char *)buf; p - (u_char *)buf < 32; p += 8) {
439 		DBG("%02x: %02x %02x %02x %02x %02x %02x %02x %02x"
440 		    "  %c%c%c%c%c%c%c%c", (p - (u_char *)buf),
441 		    p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7],
442 		    DISP(p[0]), DISP(p[1]), DISP(p[2]), DISP(p[3]),
443 		    DISP(p[4]), DISP(p[5]), DISP(p[6]), DISP(p[7]));
444 	    }
445 	}
446 #undef DISP
447 #endif
448 	return (smb_error);
449 }
450 
451 /********************************************************************
452 			OTHER FUNCTIONS
453 ********************************************************************/
454 
455 /*
456  * This table describes what interrupts we should ever expect to
457  * see after each ICH command, not including the SMBALERT interrupt.
458  */
459 static const u_int8_t ichsmb_state_irqs[] = {
460 	/* quick */
461 	(ICH_HST_STA_BUS_ERR | ICH_HST_STA_DEV_ERR | ICH_HST_STA_INTR),
462 	/* byte */
463 	(ICH_HST_STA_BUS_ERR | ICH_HST_STA_DEV_ERR | ICH_HST_STA_INTR),
464 	/* byte data */
465 	(ICH_HST_STA_BUS_ERR | ICH_HST_STA_DEV_ERR | ICH_HST_STA_INTR),
466 	/* word data */
467 	(ICH_HST_STA_BUS_ERR | ICH_HST_STA_DEV_ERR | ICH_HST_STA_INTR),
468 	/* process call */
469 	(ICH_HST_STA_BUS_ERR | ICH_HST_STA_DEV_ERR | ICH_HST_STA_INTR),
470 	/* block */
471 	(ICH_HST_STA_BUS_ERR | ICH_HST_STA_DEV_ERR | ICH_HST_STA_INTR
472 	    | ICH_HST_STA_BYTE_DONE_STS),
473 	/* i2c read (not used) */
474 	(ICH_HST_STA_BUS_ERR | ICH_HST_STA_DEV_ERR | ICH_HST_STA_INTR
475 	    | ICH_HST_STA_BYTE_DONE_STS)
476 };
477 
478 /*
479  * Interrupt handler. This handler is bus-independent. Note that our
480  * interrupt may be shared, so we must handle "false" interrupts.
481  */
482 void
483 ichsmb_device_intr(void *cookie)
484 {
485 	const sc_p sc = cookie;
486 	const device_t dev = sc->dev;
487 	const int maxloops = 16;
488 	u_int8_t status;
489 	u_int8_t ok_bits;
490 	int cmd_index;
491         int count;
492 
493 	mtx_lock(&sc->mutex);
494 	for (count = 0; count < maxloops; count++) {
495 
496 		/* Get and reset status bits */
497 		status = bus_space_read_1(sc->io_bst, sc->io_bsh, ICH_HST_STA);
498 #if ICHSMB_DEBUG
499 		if ((status & ~(ICH_HST_STA_INUSE_STS | ICH_HST_STA_HOST_BUSY))
500 		    || count > 0) {
501 			DBG("%d stat=0x%02x\n", count, status);
502 		}
503 #endif
504 		status &= ~(ICH_HST_STA_INUSE_STS | ICH_HST_STA_HOST_BUSY);
505 		if (status == 0)
506 			break;
507 
508 		/* Check for unexpected interrupt */
509 		ok_bits = ICH_HST_STA_SMBALERT_STS;
510 		cmd_index = sc->ich_cmd >> 2;
511 		if (sc->ich_cmd != -1) {
512 			KASSERT(cmd_index < sizeof(ichsmb_state_irqs),
513 			    ("%s: ich_cmd=%d", device_get_nameunit(dev),
514 			    sc->ich_cmd));
515 			ok_bits |= ichsmb_state_irqs[cmd_index];
516 		}
517 		if ((status & ~ok_bits) != 0) {
518 			log(LOG_ERR, "%s: irq 0x%02x during %d\n",
519 			    device_get_nameunit(dev), status, cmd_index);
520 			bus_space_write_1(sc->io_bst, sc->io_bsh,
521 			    ICH_HST_STA, (status & ~ok_bits));
522 			continue;
523 		}
524 
525 		/* Handle SMBALERT interrupt */
526 		if (status & ICH_HST_STA_SMBALERT_STS) {
527 			static int smbalert_count = 16;
528 			if (smbalert_count > 0) {
529 				log(LOG_WARNING, "%s: SMBALERT# rec'd\n",
530 				    device_get_nameunit(dev));
531 				if (--smbalert_count == 0) {
532 					log(LOG_WARNING,
533 					    "%s: not logging anymore\n",
534 					    device_get_nameunit(dev));
535 				}
536 			}
537 		}
538 
539 		/* Check for bus error */
540 		if (status & ICH_HST_STA_BUS_ERR) {
541 			sc->smb_error = SMB_ECOLLI;	/* XXX SMB_EBUSERR? */
542 			goto finished;
543 		}
544 
545 		/* Check for device error */
546 		if (status & ICH_HST_STA_DEV_ERR) {
547 			sc->smb_error = SMB_ENOACK;	/* or SMB_ETIMEOUT? */
548 			goto finished;
549 		}
550 
551 		/* Check for byte completion in block transfer */
552 		if (status & ICH_HST_STA_BYTE_DONE_STS) {
553 			if (sc->block_write) {
554 				if (sc->block_index < sc->block_count) {
555 
556 					/* Write next byte */
557 					bus_space_write_1(sc->io_bst,
558 					    sc->io_bsh, ICH_BLOCK_DB,
559 					    sc->block_data[sc->block_index++]);
560 				}
561 			} else {
562 
563 				/* First interrupt, get the count also */
564 				if (sc->block_index == 0) {
565 					sc->block_count = bus_space_read_1(
566 					    sc->io_bst, sc->io_bsh, ICH_D0);
567 				}
568 
569 				/* Get next byte, if any */
570 				if (sc->block_index < sc->block_count) {
571 
572 					/* Read next byte */
573 					sc->block_data[sc->block_index++] =
574 					    bus_space_read_1(sc->io_bst,
575 					      sc->io_bsh, ICH_BLOCK_DB);
576 
577 					/* Set "LAST_BYTE" bit before reading
578 					   the last byte of block data */
579 					if (sc->block_index
580 					    >= sc->block_count - 1) {
581 						bus_space_write_1(sc->io_bst,
582 						    sc->io_bsh, ICH_HST_CNT,
583 						    ICH_HST_CNT_LAST_BYTE
584 							| ICH_HST_CNT_INTREN
585 							| sc->ich_cmd);
586 					}
587 				}
588 			}
589 		}
590 
591 		/* Check command completion */
592 		if (status & ICH_HST_STA_INTR) {
593 			sc->smb_error = SMB_ENOERR;
594 finished:
595 			sc->ich_cmd = -1;
596 			bus_space_write_1(sc->io_bst, sc->io_bsh,
597 			    ICH_HST_STA, status);
598 			wakeup(sc);
599 			break;
600 		}
601 
602 		/* Clear status bits and try again */
603 		bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_HST_STA, status);
604 	}
605 	mtx_unlock(&sc->mutex);
606 
607 	/* Too many loops? */
608 	if (count == maxloops) {
609 		log(LOG_ERR, "%s: interrupt loop, status=0x%02x\n",
610 		    device_get_nameunit(dev),
611 		    bus_space_read_1(sc->io_bst, sc->io_bsh, ICH_HST_STA));
612 	}
613 }
614 
615 /*
616  * Wait for command completion. Assumes mutex is held.
617  * Returns an SMB_* error code.
618  */
619 static int
620 ichsmb_wait(sc_p sc)
621 {
622 	const device_t dev = sc->dev;
623 	int error, smb_error;
624 
625 	KASSERT(sc->ich_cmd != -1,
626 	    ("%s: ich_cmd=%d\n", __func__ , sc->ich_cmd));
627 	mtx_assert(&sc->mutex, MA_OWNED);
628 	error = msleep(sc, &sc->mutex, PZERO, "ichsmb", hz / 4);
629 	DBG("msleep -> %d\n", error);
630 	switch (error) {
631 	case 0:
632 		smb_error = sc->smb_error;
633 		break;
634 	case EWOULDBLOCK:
635 		log(LOG_ERR, "%s: device timeout, status=0x%02x\n",
636 		    device_get_nameunit(dev),
637 		    bus_space_read_1(sc->io_bst, sc->io_bsh, ICH_HST_STA));
638 		sc->ich_cmd = -1;
639 		smb_error = SMB_ETIMEOUT;
640 		break;
641 	default:
642 		smb_error = SMB_EABORT;
643 		break;
644 	}
645 	return (smb_error);
646 }
647 
648 /*
649  * Release resources associated with device.
650  */
651 void
652 ichsmb_release_resources(sc_p sc)
653 {
654 	const device_t dev = sc->dev;
655 
656 	if (sc->irq_handle != NULL) {
657 		bus_teardown_intr(dev, sc->irq_res, sc->irq_handle);
658 		sc->irq_handle = NULL;
659 	}
660 	if (sc->irq_res != NULL) {
661 		bus_release_resource(dev,
662 		    SYS_RES_IRQ, sc->irq_rid, sc->irq_res);
663 		sc->irq_res = NULL;
664 	}
665 	if (sc->io_res != NULL) {
666 		bus_release_resource(dev,
667 		    SYS_RES_IOPORT, sc->io_rid, sc->io_res);
668 		sc->io_res = NULL;
669 	}
670 }
671 
672 int ichsmb_detach(device_t dev)
673 {
674 	const sc_p sc = device_get_softc(dev);
675 
676 	mtx_destroy(&sc->mutex);
677 	bus_generic_detach(dev);
678 	device_delete_child(dev, sc->smb);
679 	ichsmb_release_resources(sc);
680 
681 	return 0;
682 }
683