xref: /freebsd/sys/dev/ichsmb/ichsmb.c (revision f856af0466c076beef4ea9b15d088e1119a945b8)
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/module.h>
55 #include <sys/mutex.h>
56 #include <sys/syslog.h>
57 #include <sys/bus.h>
58 
59 #include <machine/bus.h>
60 #include <sys/rman.h>
61 #include <machine/resource.h>
62 
63 #include <dev/smbus/smbconf.h>
64 
65 #include <dev/ichsmb/ichsmb_var.h>
66 #include <dev/ichsmb/ichsmb_reg.h>
67 
68 /*
69  * Enable debugging by defining ICHSMB_DEBUG to a non-zero value.
70  */
71 #define ICHSMB_DEBUG	0
72 #if ICHSMB_DEBUG != 0 && defined(__CC_SUPPORTS___FUNC__)
73 #define DBG(fmt, args...)	\
74 	do { log(LOG_DEBUG, "%s: " fmt, __func__ , ## args); } while (0)
75 #else
76 #define DBG(fmt, args...)	do { } while (0)
77 #endif
78 
79 /*
80  * Our child device driver name
81  */
82 #define DRIVER_SMBUS	"smbus"
83 
84 /*
85  * Internal functions
86  */
87 static int ichsmb_wait(sc_p sc);
88 
89 /********************************************************************
90 		BUS-INDEPENDENT BUS METHODS
91 ********************************************************************/
92 
93 /*
94  * Handle probe-time duties that are independent of the bus
95  * our device lives on.
96  */
97 int
98 ichsmb_probe(device_t dev)
99 {
100 	return (BUS_PROBE_DEFAULT);
101 }
102 
103 /*
104  * Handle attach-time duties that are independent of the bus
105  * our device lives on.
106  */
107 int
108 ichsmb_attach(device_t dev)
109 {
110 	const sc_p sc = device_get_softc(dev);
111 	int error;
112 
113 	/* Add child: an instance of the "smbus" device */
114 	if ((sc->smb = device_add_child(dev, DRIVER_SMBUS, -1)) == NULL) {
115 		log(LOG_ERR, "%s: no \"%s\" child found\n",
116 		    device_get_nameunit(dev), DRIVER_SMBUS);
117 		return (ENXIO);
118 	}
119 
120 	/* Clear interrupt conditions */
121 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_HST_STA, 0xff);
122 
123 	/* Add "smbus" child */
124 	if ((error = bus_generic_attach(dev)) != 0) {
125 		log(LOG_ERR, "%s: failed to attach child: %d\n",
126 		    device_get_nameunit(dev), error);
127 		return (ENXIO);
128 	}
129 
130 	/* Create mutex */
131 	mtx_init(&sc->mutex, device_get_nameunit(dev), "ichsmb", MTX_DEF);
132 	return (0);
133 }
134 
135 /********************************************************************
136 			SMBUS METHODS
137 ********************************************************************/
138 
139 int
140 ichsmb_callback(device_t dev, int index, void *data)
141 {
142 	int smb_error = 0;
143 
144 	DBG("index=%d how=%d\n", index, data ? *(int *)data : -1);
145 	switch (index) {
146 	case SMB_REQUEST_BUS:
147 		break;
148 	case SMB_RELEASE_BUS:
149 		break;
150 	default:
151 		smb_error = SMB_EABORT;	/* XXX */
152 		break;
153 	}
154 	DBG("smb_error=%d\n", smb_error);
155 	return (smb_error);
156 }
157 
158 int
159 ichsmb_quick(device_t dev, u_char slave, int how)
160 {
161 	const sc_p sc = device_get_softc(dev);
162 	int smb_error;
163 
164 	DBG("slave=0x%02x how=%d\n", slave, how);
165 	KASSERT(sc->ich_cmd == -1,
166 	    ("%s: ich_cmd=%d\n", __func__ , sc->ich_cmd));
167 	switch (how) {
168 	case SMB_QREAD:
169 	case SMB_QWRITE:
170 		mtx_lock(&sc->mutex);
171 		sc->ich_cmd = ICH_HST_CNT_SMB_CMD_QUICK;
172 		bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_XMIT_SLVA,
173 		    (slave << 1) | (how == SMB_QREAD ?
174 	    		ICH_XMIT_SLVA_READ : ICH_XMIT_SLVA_WRITE));
175 		bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_HST_CNT,
176 		    ICH_HST_CNT_START | ICH_HST_CNT_INTREN | sc->ich_cmd);
177 		smb_error = ichsmb_wait(sc);
178 		mtx_unlock(&sc->mutex);
179 		break;
180 	default:
181 		smb_error = SMB_ENOTSUPP;
182 	}
183 	DBG("smb_error=%d\n", smb_error);
184 	return (smb_error);
185 }
186 
187 int
188 ichsmb_sendb(device_t dev, u_char slave, char byte)
189 {
190 	const sc_p sc = device_get_softc(dev);
191 	int smb_error;
192 
193 	DBG("slave=0x%02x byte=0x%02x\n", slave, (u_char)byte);
194 	KASSERT(sc->ich_cmd == -1,
195 	    ("%s: ich_cmd=%d\n", __func__ , sc->ich_cmd));
196 	mtx_lock(&sc->mutex);
197 	sc->ich_cmd = ICH_HST_CNT_SMB_CMD_BYTE;
198 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_XMIT_SLVA,
199 	    (slave << 1) | ICH_XMIT_SLVA_WRITE);
200 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_HST_CMD, byte);
201 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_HST_CNT,
202 	    ICH_HST_CNT_START | ICH_HST_CNT_INTREN | sc->ich_cmd);
203 	smb_error = ichsmb_wait(sc);
204 	mtx_unlock(&sc->mutex);
205 	DBG("smb_error=%d\n", smb_error);
206 	return (smb_error);
207 }
208 
209 int
210 ichsmb_recvb(device_t dev, u_char slave, char *byte)
211 {
212 	const sc_p sc = device_get_softc(dev);
213 	int smb_error;
214 
215 	DBG("slave=0x%02x\n", slave);
216 	KASSERT(sc->ich_cmd == -1,
217 	    ("%s: ich_cmd=%d\n", __func__ , sc->ich_cmd));
218 	mtx_lock(&sc->mutex);
219 	sc->ich_cmd = ICH_HST_CNT_SMB_CMD_BYTE;
220 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_XMIT_SLVA,
221 	    (slave << 1) | ICH_XMIT_SLVA_READ);
222 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_HST_CNT,
223 	    ICH_HST_CNT_START | ICH_HST_CNT_INTREN | sc->ich_cmd);
224 	if ((smb_error = ichsmb_wait(sc)) == SMB_ENOERR)
225 		*byte = bus_space_read_1(sc->io_bst, sc->io_bsh, ICH_D0);
226 	mtx_unlock(&sc->mutex);
227 	DBG("smb_error=%d byte=0x%02x\n", smb_error, (u_char)*byte);
228 	return (smb_error);
229 }
230 
231 int
232 ichsmb_writeb(device_t dev, u_char slave, char cmd, char byte)
233 {
234 	const sc_p sc = device_get_softc(dev);
235 	int smb_error;
236 
237 	DBG("slave=0x%02x cmd=0x%02x byte=0x%02x\n",
238 	    slave, (u_char)cmd, (u_char)byte);
239 	KASSERT(sc->ich_cmd == -1,
240 	    ("%s: ich_cmd=%d\n", __func__ , sc->ich_cmd));
241 	mtx_lock(&sc->mutex);
242 	sc->ich_cmd = ICH_HST_CNT_SMB_CMD_BYTE_DATA;
243 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_XMIT_SLVA,
244 	    (slave << 1) | ICH_XMIT_SLVA_WRITE);
245 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_HST_CMD, cmd);
246 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_D0, byte);
247 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_HST_CNT,
248 	    ICH_HST_CNT_START | ICH_HST_CNT_INTREN | sc->ich_cmd);
249 	smb_error = ichsmb_wait(sc);
250 	mtx_unlock(&sc->mutex);
251 	DBG("smb_error=%d\n", smb_error);
252 	return (smb_error);
253 }
254 
255 int
256 ichsmb_writew(device_t dev, u_char slave, char cmd, short word)
257 {
258 	const sc_p sc = device_get_softc(dev);
259 	int smb_error;
260 
261 	DBG("slave=0x%02x cmd=0x%02x word=0x%04x\n",
262 	    slave, (u_char)cmd, (u_int16_t)word);
263 	KASSERT(sc->ich_cmd == -1,
264 	    ("%s: ich_cmd=%d\n", __func__ , sc->ich_cmd));
265 	mtx_lock(&sc->mutex);
266 	sc->ich_cmd = ICH_HST_CNT_SMB_CMD_WORD_DATA;
267 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_XMIT_SLVA,
268 	    (slave << 1) | ICH_XMIT_SLVA_WRITE);
269 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_HST_CMD, cmd);
270 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_D0, word & 0xff);
271 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_D1, word >> 8);
272 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_HST_CNT,
273 	    ICH_HST_CNT_START | ICH_HST_CNT_INTREN | sc->ich_cmd);
274 	smb_error = ichsmb_wait(sc);
275 	mtx_unlock(&sc->mutex);
276 	DBG("smb_error=%d\n", smb_error);
277 	return (smb_error);
278 }
279 
280 int
281 ichsmb_readb(device_t dev, u_char slave, char cmd, char *byte)
282 {
283 	const sc_p sc = device_get_softc(dev);
284 	int smb_error;
285 
286 	DBG("slave=0x%02x cmd=0x%02x\n", slave, (u_char)cmd);
287 	KASSERT(sc->ich_cmd == -1,
288 	    ("%s: ich_cmd=%d\n", __func__ , sc->ich_cmd));
289 	mtx_lock(&sc->mutex);
290 	sc->ich_cmd = ICH_HST_CNT_SMB_CMD_BYTE_DATA;
291 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_XMIT_SLVA,
292 	    (slave << 1) | ICH_XMIT_SLVA_READ);
293 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_HST_CMD, cmd);
294 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_HST_CNT,
295 	    ICH_HST_CNT_START | ICH_HST_CNT_INTREN | sc->ich_cmd);
296 	if ((smb_error = ichsmb_wait(sc)) == SMB_ENOERR)
297 		*byte = bus_space_read_1(sc->io_bst, sc->io_bsh, ICH_D0);
298 	mtx_unlock(&sc->mutex);
299 	DBG("smb_error=%d byte=0x%02x\n", smb_error, (u_char)*byte);
300 	return (smb_error);
301 }
302 
303 int
304 ichsmb_readw(device_t dev, u_char slave, char cmd, short *word)
305 {
306 	const sc_p sc = device_get_softc(dev);
307 	int smb_error;
308 
309 	DBG("slave=0x%02x cmd=0x%02x\n", slave, (u_char)cmd);
310 	KASSERT(sc->ich_cmd == -1,
311 	    ("%s: ich_cmd=%d\n", __func__ , sc->ich_cmd));
312 	mtx_lock(&sc->mutex);
313 	sc->ich_cmd = ICH_HST_CNT_SMB_CMD_WORD_DATA;
314 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_XMIT_SLVA,
315 	    (slave << 1) | ICH_XMIT_SLVA_READ);
316 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_HST_CMD, cmd);
317 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_HST_CNT,
318 	    ICH_HST_CNT_START | ICH_HST_CNT_INTREN | sc->ich_cmd);
319 	if ((smb_error = ichsmb_wait(sc)) == SMB_ENOERR) {
320 		*word = (bus_space_read_1(sc->io_bst,
321 			sc->io_bsh, ICH_D0) & 0xff)
322 		  | (bus_space_read_1(sc->io_bst,
323 			sc->io_bsh, ICH_D1) << 8);
324 	}
325 	mtx_unlock(&sc->mutex);
326 	DBG("smb_error=%d word=0x%04x\n", smb_error, (u_int16_t)*word);
327 	return (smb_error);
328 }
329 
330 int
331 ichsmb_pcall(device_t dev, u_char slave, char cmd, short sdata, short *rdata)
332 {
333 	const sc_p sc = device_get_softc(dev);
334 	int smb_error;
335 
336 	DBG("slave=0x%02x cmd=0x%02x sdata=0x%04x\n",
337 	    slave, (u_char)cmd, (u_int16_t)sdata);
338 	KASSERT(sc->ich_cmd == -1,
339 	    ("%s: ich_cmd=%d\n", __func__ , sc->ich_cmd));
340 	mtx_lock(&sc->mutex);
341 	sc->ich_cmd = ICH_HST_CNT_SMB_CMD_PROC_CALL;
342 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_XMIT_SLVA,
343 	    (slave << 1) | ICH_XMIT_SLVA_WRITE);
344 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_HST_CMD, cmd);
345 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_D0, sdata & 0xff);
346 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_D1, sdata >> 8);
347 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_HST_CNT,
348 	    ICH_HST_CNT_START | ICH_HST_CNT_INTREN | sc->ich_cmd);
349 	if ((smb_error = ichsmb_wait(sc)) == SMB_ENOERR) {
350 		*rdata = (bus_space_read_1(sc->io_bst,
351 			sc->io_bsh, ICH_D0) & 0xff)
352 		  | (bus_space_read_1(sc->io_bst,
353 			sc->io_bsh, ICH_D1) << 8);
354 	}
355 	mtx_unlock(&sc->mutex);
356 	DBG("smb_error=%d rdata=0x%04x\n", smb_error, (u_int16_t)*rdata);
357 	return (smb_error);
358 }
359 
360 int
361 ichsmb_bwrite(device_t dev, u_char slave, char cmd, u_char count, char *buf)
362 {
363 	const sc_p sc = device_get_softc(dev);
364 	int smb_error;
365 
366 	DBG("slave=0x%02x cmd=0x%02x count=%d\n", slave, (u_char)cmd, count);
367 #if ICHSMB_DEBUG
368 #define DISP(ch)	(((ch) < 0x20 || (ch) >= 0x7e) ? '.' : (ch))
369 	{
370 	    u_char *p;
371 
372 	    for (p = (u_char *)buf; p - (u_char *)buf < 32; p += 8) {
373 		DBG("%02x: %02x %02x %02x %02x %02x %02x %02x %02x"
374 		    "  %c%c%c%c%c%c%c%c", (p - (u_char *)buf),
375 		    p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7],
376 		    DISP(p[0]), DISP(p[1]), DISP(p[2]), DISP(p[3]),
377 		    DISP(p[4]), DISP(p[5]), DISP(p[6]), DISP(p[7]));
378 	    }
379 	}
380 #undef DISP
381 #endif
382 	KASSERT(sc->ich_cmd == -1,
383 	    ("%s: ich_cmd=%d\n", __func__ , sc->ich_cmd));
384 	if (count < 1 || count > 32)
385 		return (SMB_EINVAL);
386 	bcopy(buf, sc->block_data, count);
387 	sc->block_count = count;
388 	sc->block_index = 1;
389 	sc->block_write = 1;
390 
391 	mtx_lock(&sc->mutex);
392 	sc->ich_cmd = ICH_HST_CNT_SMB_CMD_BLOCK;
393 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_XMIT_SLVA,
394 	    (slave << 1) | ICH_XMIT_SLVA_WRITE);
395 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_HST_CMD, cmd);
396 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_D0, count);
397 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_BLOCK_DB, buf[0]);
398 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_HST_CNT,
399 	    ICH_HST_CNT_START | ICH_HST_CNT_INTREN | sc->ich_cmd);
400 	smb_error = ichsmb_wait(sc);
401 	mtx_unlock(&sc->mutex);
402 	DBG("smb_error=%d\n", smb_error);
403 	return (smb_error);
404 }
405 
406 int
407 ichsmb_bread(device_t dev, u_char slave, char cmd, u_char *count, char *buf)
408 {
409 	const sc_p sc = device_get_softc(dev);
410 	int smb_error;
411 
412 	DBG("slave=0x%02x cmd=0x%02x count=%d\n", slave, (u_char)cmd, count);
413 	KASSERT(sc->ich_cmd == -1,
414 	    ("%s: ich_cmd=%d\n", __func__ , sc->ich_cmd));
415 	if (*count < 1 || *count > 32)
416 		return (SMB_EINVAL);
417 	bzero(sc->block_data, sizeof(sc->block_data));
418 	sc->block_count = 0;
419 	sc->block_index = 0;
420 	sc->block_write = 0;
421 
422 	mtx_lock(&sc->mutex);
423 	sc->ich_cmd = ICH_HST_CNT_SMB_CMD_BLOCK;
424 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_XMIT_SLVA,
425 	    (slave << 1) | ICH_XMIT_SLVA_READ);
426 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_HST_CMD, cmd);
427 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_D0, *count); /* XXX? */
428 	bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_HST_CNT,
429 	    ICH_HST_CNT_START | ICH_HST_CNT_INTREN | sc->ich_cmd);
430 	if ((smb_error = ichsmb_wait(sc)) == SMB_ENOERR) {
431 		bcopy(sc->block_data, buf, min(sc->block_count, *count));
432 		*count = sc->block_count;
433 	}
434 	mtx_unlock(&sc->mutex);
435 	DBG("smb_error=%d\n", smb_error);
436 #if ICHSMB_DEBUG
437 #define DISP(ch)	(((ch) < 0x20 || (ch) >= 0x7e) ? '.' : (ch))
438 	{
439 	    u_char *p;
440 
441 	    for (p = (u_char *)buf; p - (u_char *)buf < 32; p += 8) {
442 		DBG("%02x: %02x %02x %02x %02x %02x %02x %02x %02x"
443 		    "  %c%c%c%c%c%c%c%c", (p - (u_char *)buf),
444 		    p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7],
445 		    DISP(p[0]), DISP(p[1]), DISP(p[2]), DISP(p[3]),
446 		    DISP(p[4]), DISP(p[5]), DISP(p[6]), DISP(p[7]));
447 	    }
448 	}
449 #undef DISP
450 #endif
451 	return (smb_error);
452 }
453 
454 /********************************************************************
455 			OTHER FUNCTIONS
456 ********************************************************************/
457 
458 /*
459  * This table describes what interrupts we should ever expect to
460  * see after each ICH command, not including the SMBALERT interrupt.
461  */
462 static const u_int8_t ichsmb_state_irqs[] = {
463 	/* quick */
464 	(ICH_HST_STA_BUS_ERR | ICH_HST_STA_DEV_ERR | ICH_HST_STA_INTR),
465 	/* byte */
466 	(ICH_HST_STA_BUS_ERR | ICH_HST_STA_DEV_ERR | ICH_HST_STA_INTR),
467 	/* byte data */
468 	(ICH_HST_STA_BUS_ERR | ICH_HST_STA_DEV_ERR | ICH_HST_STA_INTR),
469 	/* word data */
470 	(ICH_HST_STA_BUS_ERR | ICH_HST_STA_DEV_ERR | ICH_HST_STA_INTR),
471 	/* process call */
472 	(ICH_HST_STA_BUS_ERR | ICH_HST_STA_DEV_ERR | ICH_HST_STA_INTR),
473 	/* block */
474 	(ICH_HST_STA_BUS_ERR | ICH_HST_STA_DEV_ERR | ICH_HST_STA_INTR
475 	    | ICH_HST_STA_BYTE_DONE_STS),
476 	/* i2c read (not used) */
477 	(ICH_HST_STA_BUS_ERR | ICH_HST_STA_DEV_ERR | ICH_HST_STA_INTR
478 	    | ICH_HST_STA_BYTE_DONE_STS)
479 };
480 
481 /*
482  * Interrupt handler. This handler is bus-independent. Note that our
483  * interrupt may be shared, so we must handle "false" interrupts.
484  */
485 void
486 ichsmb_device_intr(void *cookie)
487 {
488 	const sc_p sc = cookie;
489 	const device_t dev = sc->dev;
490 	const int maxloops = 16;
491 	u_int8_t status;
492 	u_int8_t ok_bits;
493 	int cmd_index;
494         int count;
495 
496 	mtx_lock(&sc->mutex);
497 	for (count = 0; count < maxloops; count++) {
498 
499 		/* Get and reset status bits */
500 		status = bus_space_read_1(sc->io_bst, sc->io_bsh, ICH_HST_STA);
501 #if ICHSMB_DEBUG
502 		if ((status & ~(ICH_HST_STA_INUSE_STS | ICH_HST_STA_HOST_BUSY))
503 		    || count > 0) {
504 			DBG("%d stat=0x%02x\n", count, status);
505 		}
506 #endif
507 		status &= ~(ICH_HST_STA_INUSE_STS | ICH_HST_STA_HOST_BUSY);
508 		if (status == 0)
509 			break;
510 
511 		/* Check for unexpected interrupt */
512 		ok_bits = ICH_HST_STA_SMBALERT_STS;
513 		cmd_index = sc->ich_cmd >> 2;
514 		if (sc->ich_cmd != -1) {
515 			KASSERT(cmd_index < sizeof(ichsmb_state_irqs),
516 			    ("%s: ich_cmd=%d", device_get_nameunit(dev),
517 			    sc->ich_cmd));
518 			ok_bits |= ichsmb_state_irqs[cmd_index];
519 		}
520 		if ((status & ~ok_bits) != 0) {
521 			log(LOG_ERR, "%s: irq 0x%02x during %d\n",
522 			    device_get_nameunit(dev), status, cmd_index);
523 			bus_space_write_1(sc->io_bst, sc->io_bsh,
524 			    ICH_HST_STA, (status & ~ok_bits));
525 			continue;
526 		}
527 
528 		/* Handle SMBALERT interrupt */
529 		if (status & ICH_HST_STA_SMBALERT_STS) {
530 			static int smbalert_count = 16;
531 			if (smbalert_count > 0) {
532 				log(LOG_WARNING, "%s: SMBALERT# rec'd\n",
533 				    device_get_nameunit(dev));
534 				if (--smbalert_count == 0) {
535 					log(LOG_WARNING,
536 					    "%s: not logging anymore\n",
537 					    device_get_nameunit(dev));
538 				}
539 			}
540 		}
541 
542 		/* Check for bus error */
543 		if (status & ICH_HST_STA_BUS_ERR) {
544 			sc->smb_error = SMB_ECOLLI;	/* XXX SMB_EBUSERR? */
545 			goto finished;
546 		}
547 
548 		/* Check for device error */
549 		if (status & ICH_HST_STA_DEV_ERR) {
550 			sc->smb_error = SMB_ENOACK;	/* or SMB_ETIMEOUT? */
551 			goto finished;
552 		}
553 
554 		/* Check for byte completion in block transfer */
555 		if (status & ICH_HST_STA_BYTE_DONE_STS) {
556 			if (sc->block_write) {
557 				if (sc->block_index < sc->block_count) {
558 
559 					/* Write next byte */
560 					bus_space_write_1(sc->io_bst,
561 					    sc->io_bsh, ICH_BLOCK_DB,
562 					    sc->block_data[sc->block_index++]);
563 				}
564 			} else {
565 
566 				/* First interrupt, get the count also */
567 				if (sc->block_index == 0) {
568 					sc->block_count = bus_space_read_1(
569 					    sc->io_bst, sc->io_bsh, ICH_D0);
570 				}
571 
572 				/* Get next byte, if any */
573 				if (sc->block_index < sc->block_count) {
574 
575 					/* Read next byte */
576 					sc->block_data[sc->block_index++] =
577 					    bus_space_read_1(sc->io_bst,
578 					      sc->io_bsh, ICH_BLOCK_DB);
579 
580 					/* Set "LAST_BYTE" bit before reading
581 					   the last byte of block data */
582 					if (sc->block_index
583 					    >= sc->block_count - 1) {
584 						bus_space_write_1(sc->io_bst,
585 						    sc->io_bsh, ICH_HST_CNT,
586 						    ICH_HST_CNT_LAST_BYTE
587 							| ICH_HST_CNT_INTREN
588 							| sc->ich_cmd);
589 					}
590 				}
591 			}
592 		}
593 
594 		/* Check command completion */
595 		if (status & ICH_HST_STA_INTR) {
596 			sc->smb_error = SMB_ENOERR;
597 finished:
598 			sc->ich_cmd = -1;
599 			bus_space_write_1(sc->io_bst, sc->io_bsh,
600 			    ICH_HST_STA, status);
601 			wakeup(sc);
602 			break;
603 		}
604 
605 		/* Clear status bits and try again */
606 		bus_space_write_1(sc->io_bst, sc->io_bsh, ICH_HST_STA, status);
607 	}
608 	mtx_unlock(&sc->mutex);
609 
610 	/* Too many loops? */
611 	if (count == maxloops) {
612 		log(LOG_ERR, "%s: interrupt loop, status=0x%02x\n",
613 		    device_get_nameunit(dev),
614 		    bus_space_read_1(sc->io_bst, sc->io_bsh, ICH_HST_STA));
615 	}
616 }
617 
618 /*
619  * Wait for command completion. Assumes mutex is held.
620  * Returns an SMB_* error code.
621  */
622 static int
623 ichsmb_wait(sc_p sc)
624 {
625 	const device_t dev = sc->dev;
626 	int error, smb_error;
627 
628 	KASSERT(sc->ich_cmd != -1,
629 	    ("%s: ich_cmd=%d\n", __func__ , sc->ich_cmd));
630 	mtx_assert(&sc->mutex, MA_OWNED);
631 	error = msleep(sc, &sc->mutex, PZERO, "ichsmb", hz / 4);
632 	DBG("msleep -> %d\n", error);
633 	switch (error) {
634 	case 0:
635 		smb_error = sc->smb_error;
636 		break;
637 	case EWOULDBLOCK:
638 		log(LOG_ERR, "%s: device timeout, status=0x%02x\n",
639 		    device_get_nameunit(dev),
640 		    bus_space_read_1(sc->io_bst, sc->io_bsh, ICH_HST_STA));
641 		sc->ich_cmd = -1;
642 		smb_error = SMB_ETIMEOUT;
643 		break;
644 	default:
645 		smb_error = SMB_EABORT;
646 		break;
647 	}
648 	return (smb_error);
649 }
650 
651 /*
652  * Release resources associated with device.
653  */
654 void
655 ichsmb_release_resources(sc_p sc)
656 {
657 	const device_t dev = sc->dev;
658 
659 	if (sc->irq_handle != NULL) {
660 		bus_teardown_intr(dev, sc->irq_res, sc->irq_handle);
661 		sc->irq_handle = NULL;
662 	}
663 	if (sc->irq_res != NULL) {
664 		bus_release_resource(dev,
665 		    SYS_RES_IRQ, sc->irq_rid, sc->irq_res);
666 		sc->irq_res = NULL;
667 	}
668 	if (sc->io_res != NULL) {
669 		bus_release_resource(dev,
670 		    SYS_RES_IOPORT, sc->io_rid, sc->io_res);
671 		sc->io_res = NULL;
672 	}
673 }
674 
675 int
676 ichsmb_detach(device_t dev)
677 {
678 	const sc_p sc = device_get_softc(dev);
679 	int error;
680 
681 	error = bus_generic_detach(dev);
682 	if (error)
683 		return (error);
684 	device_delete_child(dev, sc->smb);
685 	ichsmb_release_resources(sc);
686 	mtx_destroy(&sc->mutex);
687 
688 	return 0;
689 }
690 
691 DRIVER_MODULE(smbus, ichsmb, smbus_driver, smbus_devclass, 0, 0);
692