xref: /openbmc/linux/drivers/input/serio/hil_mlc.c (revision 9cfc5c90)
1 /*
2  * HIL MLC state machine and serio interface driver
3  *
4  * Copyright (c) 2001 Brian S. Julin
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions, and the following disclaimer,
12  *    without modification.
13  * 2. The name of the author may not be used to endorse or promote products
14  *    derived from this software without specific prior written permission.
15  *
16  * Alternatively, this software may be distributed under the terms of the
17  * GNU General Public License ("GPL").
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
23  * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  *
29  * References:
30  * HP-HIL Technical Reference Manual.  Hewlett Packard Product No. 45918A
31  *
32  *
33  *	Driver theory of operation:
34  *
35  *	Some access methods and an ISR is defined by the sub-driver
36  *	(e.g. hp_sdc_mlc.c).  These methods are expected to provide a
37  *	few bits of logic in addition to raw access to the HIL MLC,
38  *	specifically, the ISR, which is entirely registered by the
39  *	sub-driver and invoked directly, must check for record
40  *	termination or packet match, at which point a semaphore must
41  *	be cleared and then the hil_mlcs_tasklet must be scheduled.
42  *
43  *	The hil_mlcs_tasklet processes the state machine for all MLCs
44  *	each time it runs, checking each MLC's progress at the current
45  *	node in the state machine, and moving the MLC to subsequent nodes
46  *	in the state machine when appropriate.  It will reschedule
47  *	itself if output is pending.  (This rescheduling should be replaced
48  *	at some point with a sub-driver-specific mechanism.)
49  *
50  *	A timer task prods the tasklet once per second to prevent
51  *	hangups when attached devices do not return expected data
52  *	and to initiate probes of the loop for new devices.
53  */
54 
55 #include <linux/hil_mlc.h>
56 #include <linux/errno.h>
57 #include <linux/kernel.h>
58 #include <linux/module.h>
59 #include <linux/init.h>
60 #include <linux/interrupt.h>
61 #include <linux/slab.h>
62 #include <linux/timer.h>
63 #include <linux/list.h>
64 
65 MODULE_AUTHOR("Brian S. Julin <bri@calyx.com>");
66 MODULE_DESCRIPTION("HIL MLC serio");
67 MODULE_LICENSE("Dual BSD/GPL");
68 
69 EXPORT_SYMBOL(hil_mlc_register);
70 EXPORT_SYMBOL(hil_mlc_unregister);
71 
72 #define PREFIX "HIL MLC: "
73 
74 static LIST_HEAD(hil_mlcs);
75 static DEFINE_RWLOCK(hil_mlcs_lock);
76 static struct timer_list	hil_mlcs_kicker;
77 static int			hil_mlcs_probe;
78 
79 static void hil_mlcs_process(unsigned long unused);
80 static DECLARE_TASKLET_DISABLED(hil_mlcs_tasklet, hil_mlcs_process, 0);
81 
82 
83 /* #define HIL_MLC_DEBUG */
84 
85 /********************** Device info/instance management **********************/
86 
87 static void hil_mlc_clear_di_map(hil_mlc *mlc, int val)
88 {
89 	int j;
90 
91 	for (j = val; j < 7 ; j++)
92 		mlc->di_map[j] = -1;
93 }
94 
95 static void hil_mlc_clear_di_scratch(hil_mlc *mlc)
96 {
97 	memset(&mlc->di_scratch, 0, sizeof(mlc->di_scratch));
98 }
99 
100 static void hil_mlc_copy_di_scratch(hil_mlc *mlc, int idx)
101 {
102 	memcpy(&mlc->di[idx], &mlc->di_scratch, sizeof(mlc->di_scratch));
103 }
104 
105 static int hil_mlc_match_di_scratch(hil_mlc *mlc)
106 {
107 	int idx;
108 
109 	for (idx = 0; idx < HIL_MLC_DEVMEM; idx++) {
110 		int j, found = 0;
111 
112 		/* In-use slots are not eligible. */
113 		for (j = 0; j < 7 ; j++)
114 			if (mlc->di_map[j] == idx)
115 				found++;
116 
117 		if (found)
118 			continue;
119 
120 		if (!memcmp(mlc->di + idx, &mlc->di_scratch,
121 				sizeof(mlc->di_scratch)))
122 			break;
123 	}
124 	return idx >= HIL_MLC_DEVMEM ? -1 : idx;
125 }
126 
127 static int hil_mlc_find_free_di(hil_mlc *mlc)
128 {
129 	int idx;
130 
131 	/* TODO: Pick all-zero slots first, failing that,
132 	 * randomize the slot picked among those eligible.
133 	 */
134 	for (idx = 0; idx < HIL_MLC_DEVMEM; idx++) {
135 		int j, found = 0;
136 
137 		for (j = 0; j < 7 ; j++)
138 			if (mlc->di_map[j] == idx)
139 				found++;
140 
141 		if (!found)
142 			break;
143 	}
144 
145 	return idx; /* Note: It is guaranteed at least one above will match */
146 }
147 
148 static inline void hil_mlc_clean_serio_map(hil_mlc *mlc)
149 {
150 	int idx;
151 
152 	for (idx = 0; idx < HIL_MLC_DEVMEM; idx++) {
153 		int j, found = 0;
154 
155 		for (j = 0; j < 7 ; j++)
156 			if (mlc->di_map[j] == idx)
157 				found++;
158 
159 		if (!found)
160 			mlc->serio_map[idx].di_revmap = -1;
161 	}
162 }
163 
164 static void hil_mlc_send_polls(hil_mlc *mlc)
165 {
166 	int did, i, cnt;
167 	struct serio *serio;
168 	struct serio_driver *drv;
169 
170 	i = cnt = 0;
171 	did = (mlc->ipacket[0] & HIL_PKT_ADDR_MASK) >> 8;
172 	serio = did ? mlc->serio[mlc->di_map[did - 1]] : NULL;
173 	drv = (serio != NULL) ? serio->drv : NULL;
174 
175 	while (mlc->icount < 15 - i) {
176 		hil_packet p;
177 
178 		p = mlc->ipacket[i];
179 		if (did != (p & HIL_PKT_ADDR_MASK) >> 8) {
180 			if (drv && drv->interrupt) {
181 				drv->interrupt(serio, 0, 0);
182 				drv->interrupt(serio, HIL_ERR_INT >> 16, 0);
183 				drv->interrupt(serio, HIL_PKT_CMD >> 8,  0);
184 				drv->interrupt(serio, HIL_CMD_POL + cnt, 0);
185 			}
186 
187 			did = (p & HIL_PKT_ADDR_MASK) >> 8;
188 			serio = did ? mlc->serio[mlc->di_map[did-1]] : NULL;
189 			drv = (serio != NULL) ? serio->drv : NULL;
190 			cnt = 0;
191 		}
192 
193 		cnt++;
194 		i++;
195 
196 		if (drv && drv->interrupt) {
197 			drv->interrupt(serio, (p >> 24), 0);
198 			drv->interrupt(serio, (p >> 16) & 0xff, 0);
199 			drv->interrupt(serio, (p >> 8) & ~HIL_PKT_ADDR_MASK, 0);
200 			drv->interrupt(serio, p & 0xff, 0);
201 		}
202 	}
203 }
204 
205 /*************************** State engine *********************************/
206 
207 #define HILSEN_SCHED	0x000100	/* Schedule the tasklet		*/
208 #define HILSEN_BREAK	0x000200	/* Wait until next pass		*/
209 #define HILSEN_UP	0x000400	/* relative node#, decrement	*/
210 #define HILSEN_DOWN	0x000800	/* relative node#, increment	*/
211 #define HILSEN_FOLLOW	0x001000	/* use retval as next node#	*/
212 
213 #define HILSEN_MASK	0x0000ff
214 #define HILSEN_START	0
215 #define HILSEN_RESTART	1
216 #define HILSEN_DHR	9
217 #define HILSEN_DHR2	10
218 #define HILSEN_IFC	14
219 #define HILSEN_HEAL0	16
220 #define HILSEN_HEAL	18
221 #define HILSEN_ACF      21
222 #define HILSEN_ACF2	22
223 #define HILSEN_DISC0	25
224 #define HILSEN_DISC	27
225 #define HILSEN_MATCH	40
226 #define HILSEN_OPERATE	41
227 #define HILSEN_PROBE	44
228 #define HILSEN_DSR	52
229 #define HILSEN_REPOLL	55
230 #define HILSEN_IFCACF	58
231 #define HILSEN_END	60
232 
233 #define HILSEN_NEXT	(HILSEN_DOWN | 1)
234 #define HILSEN_SAME	(HILSEN_DOWN | 0)
235 #define HILSEN_LAST	(HILSEN_UP | 1)
236 
237 #define HILSEN_DOZE	(HILSEN_SAME | HILSEN_SCHED | HILSEN_BREAK)
238 #define HILSEN_SLEEP	(HILSEN_SAME | HILSEN_BREAK)
239 
240 static int hilse_match(hil_mlc *mlc, int unused)
241 {
242 	int rc;
243 
244 	rc = hil_mlc_match_di_scratch(mlc);
245 	if (rc == -1) {
246 		rc = hil_mlc_find_free_di(mlc);
247 		if (rc == -1)
248 			goto err;
249 
250 #ifdef HIL_MLC_DEBUG
251 		printk(KERN_DEBUG PREFIX "new in slot %i\n", rc);
252 #endif
253 		hil_mlc_copy_di_scratch(mlc, rc);
254 		mlc->di_map[mlc->ddi] = rc;
255 		mlc->serio_map[rc].di_revmap = mlc->ddi;
256 		hil_mlc_clean_serio_map(mlc);
257 		serio_rescan(mlc->serio[rc]);
258 		return -1;
259 	}
260 
261 	mlc->di_map[mlc->ddi] = rc;
262 #ifdef HIL_MLC_DEBUG
263 	printk(KERN_DEBUG PREFIX "same in slot %i\n", rc);
264 #endif
265 	mlc->serio_map[rc].di_revmap = mlc->ddi;
266 	hil_mlc_clean_serio_map(mlc);
267 	return 0;
268 
269  err:
270 	printk(KERN_ERR PREFIX "Residual device slots exhausted, close some serios!\n");
271 	return 1;
272 }
273 
274 /* An LCV used to prevent runaway loops, forces 5 second sleep when reset. */
275 static int hilse_init_lcv(hil_mlc *mlc, int unused)
276 {
277 	struct timeval tv;
278 
279 	do_gettimeofday(&tv);
280 
281 	if (mlc->lcv && (tv.tv_sec - mlc->lcv_tv.tv_sec) < 5)
282 		return -1;
283 
284 	mlc->lcv_tv = tv;
285 	mlc->lcv = 0;
286 
287 	return 0;
288 }
289 
290 static int hilse_inc_lcv(hil_mlc *mlc, int lim)
291 {
292 	return mlc->lcv++ >= lim ? -1 : 0;
293 }
294 
295 #if 0
296 static int hilse_set_lcv(hil_mlc *mlc, int val)
297 {
298 	mlc->lcv = val;
299 
300 	return 0;
301 }
302 #endif
303 
304 /* Management of the discovered device index (zero based, -1 means no devs) */
305 static int hilse_set_ddi(hil_mlc *mlc, int val)
306 {
307 	mlc->ddi = val;
308 	hil_mlc_clear_di_map(mlc, val + 1);
309 
310 	return 0;
311 }
312 
313 static int hilse_dec_ddi(hil_mlc *mlc, int unused)
314 {
315 	mlc->ddi--;
316 	if (mlc->ddi <= -1) {
317 		mlc->ddi = -1;
318 		hil_mlc_clear_di_map(mlc, 0);
319 		return -1;
320 	}
321 	hil_mlc_clear_di_map(mlc, mlc->ddi + 1);
322 
323 	return 0;
324 }
325 
326 static int hilse_inc_ddi(hil_mlc *mlc, int unused)
327 {
328 	BUG_ON(mlc->ddi >= 6);
329 	mlc->ddi++;
330 
331 	return 0;
332 }
333 
334 static int hilse_take_idd(hil_mlc *mlc, int unused)
335 {
336 	int i;
337 
338 	/* Help the state engine:
339 	 * Is this a real IDD response or just an echo?
340 	 *
341 	 * Real IDD response does not start with a command.
342 	 */
343 	if (mlc->ipacket[0] & HIL_PKT_CMD)
344 		goto bail;
345 
346 	/* Should have the command echoed further down. */
347 	for (i = 1; i < 16; i++) {
348 		if (((mlc->ipacket[i] & HIL_PKT_ADDR_MASK) ==
349 		     (mlc->ipacket[0] & HIL_PKT_ADDR_MASK)) &&
350 		    (mlc->ipacket[i] & HIL_PKT_CMD) &&
351 		    ((mlc->ipacket[i] & HIL_PKT_DATA_MASK) == HIL_CMD_IDD))
352 			break;
353 	}
354 	if (i > 15)
355 		goto bail;
356 
357 	/* And the rest of the packets should still be clear. */
358 	while (++i < 16)
359 		if (mlc->ipacket[i])
360 			break;
361 
362 	if (i < 16)
363 		goto bail;
364 
365 	for (i = 0; i < 16; i++)
366 		mlc->di_scratch.idd[i] =
367 			mlc->ipacket[i] & HIL_PKT_DATA_MASK;
368 
369 	/* Next step is to see if RSC supported */
370 	if (mlc->di_scratch.idd[1] & HIL_IDD_HEADER_RSC)
371 		return HILSEN_NEXT;
372 
373 	if (mlc->di_scratch.idd[1] & HIL_IDD_HEADER_EXD)
374 		return HILSEN_DOWN | 4;
375 
376 	return 0;
377 
378  bail:
379 	mlc->ddi--;
380 
381 	return -1; /* This should send us off to ACF */
382 }
383 
384 static int hilse_take_rsc(hil_mlc *mlc, int unused)
385 {
386 	int i;
387 
388 	for (i = 0; i < 16; i++)
389 		mlc->di_scratch.rsc[i] =
390 			mlc->ipacket[i] & HIL_PKT_DATA_MASK;
391 
392 	/* Next step is to see if EXD supported (IDD has already been read) */
393 	if (mlc->di_scratch.idd[1] & HIL_IDD_HEADER_EXD)
394 		return HILSEN_NEXT;
395 
396 	return 0;
397 }
398 
399 static int hilse_take_exd(hil_mlc *mlc, int unused)
400 {
401 	int i;
402 
403 	for (i = 0; i < 16; i++)
404 		mlc->di_scratch.exd[i] =
405 			mlc->ipacket[i] & HIL_PKT_DATA_MASK;
406 
407 	/* Next step is to see if RNM supported. */
408 	if (mlc->di_scratch.exd[0] & HIL_EXD_HEADER_RNM)
409 		return HILSEN_NEXT;
410 
411 	return 0;
412 }
413 
414 static int hilse_take_rnm(hil_mlc *mlc, int unused)
415 {
416 	int i;
417 
418 	for (i = 0; i < 16; i++)
419 		mlc->di_scratch.rnm[i] =
420 			mlc->ipacket[i] & HIL_PKT_DATA_MASK;
421 
422 	printk(KERN_INFO PREFIX "Device name gotten: %16s\n",
423 			mlc->di_scratch.rnm);
424 
425 	return 0;
426 }
427 
428 static int hilse_operate(hil_mlc *mlc, int repoll)
429 {
430 
431 	if (mlc->opercnt == 0)
432 		hil_mlcs_probe = 0;
433 	mlc->opercnt = 1;
434 
435 	hil_mlc_send_polls(mlc);
436 
437 	if (!hil_mlcs_probe)
438 		return 0;
439 	hil_mlcs_probe = 0;
440 	mlc->opercnt = 0;
441 	return 1;
442 }
443 
444 #define FUNC(funct, funct_arg, zero_rc, neg_rc, pos_rc) \
445 { HILSE_FUNC,		{ .func = funct }, funct_arg, zero_rc, neg_rc, pos_rc },
446 #define OUT(pack) \
447 { HILSE_OUT,		{ .packet = pack }, 0, HILSEN_NEXT, HILSEN_DOZE, 0 },
448 #define CTS \
449 { HILSE_CTS,		{ .packet = 0    }, 0, HILSEN_NEXT | HILSEN_SCHED | HILSEN_BREAK, HILSEN_DOZE, 0 },
450 #define EXPECT(comp, to, got, got_wrong, timed_out) \
451 { HILSE_EXPECT,		{ .packet = comp }, to, got, got_wrong, timed_out },
452 #define EXPECT_LAST(comp, to, got, got_wrong, timed_out) \
453 { HILSE_EXPECT_LAST,	{ .packet = comp }, to, got, got_wrong, timed_out },
454 #define EXPECT_DISC(comp, to, got, got_wrong, timed_out) \
455 { HILSE_EXPECT_DISC,	{ .packet = comp }, to, got, got_wrong, timed_out },
456 #define IN(to, got, got_error, timed_out) \
457 { HILSE_IN,		{ .packet = 0    }, to, got, got_error, timed_out },
458 #define OUT_DISC(pack) \
459 { HILSE_OUT_DISC,	{ .packet = pack }, 0, 0, 0, 0 },
460 #define OUT_LAST(pack) \
461 { HILSE_OUT_LAST,	{ .packet = pack }, 0, 0, 0, 0 },
462 
463 static const struct hilse_node hil_mlc_se[HILSEN_END] = {
464 
465 	/* 0  HILSEN_START */
466 	FUNC(hilse_init_lcv, 0,	HILSEN_NEXT,	HILSEN_SLEEP,	0)
467 
468 	/* 1  HILSEN_RESTART */
469 	FUNC(hilse_inc_lcv, 10,	HILSEN_NEXT,	HILSEN_START,  0)
470 	OUT(HIL_CTRL_ONLY)			/* Disable APE */
471 	CTS
472 
473 #define TEST_PACKET(x) \
474 (HIL_PKT_CMD | (x << HIL_PKT_ADDR_SHIFT) | x << 4 | x)
475 
476 	OUT(HIL_DO_ALTER_CTRL | HIL_CTRL_TEST | TEST_PACKET(0x5))
477 	EXPECT(HIL_ERR_INT | TEST_PACKET(0x5),
478 	       2000,		HILSEN_NEXT,	HILSEN_RESTART,	HILSEN_RESTART)
479 	OUT(HIL_DO_ALTER_CTRL | HIL_CTRL_TEST | TEST_PACKET(0xa))
480 	EXPECT(HIL_ERR_INT | TEST_PACKET(0xa),
481 	       2000,		HILSEN_NEXT,	HILSEN_RESTART,	HILSEN_RESTART)
482 	OUT(HIL_CTRL_ONLY | 0)			/* Disable test mode */
483 
484 	/* 9  HILSEN_DHR */
485 	FUNC(hilse_init_lcv, 0,	HILSEN_NEXT,	HILSEN_SLEEP,	0)
486 
487 	/* 10 HILSEN_DHR2 */
488 	FUNC(hilse_inc_lcv, 10,	HILSEN_NEXT,	HILSEN_START,	0)
489 	FUNC(hilse_set_ddi, -1,	HILSEN_NEXT,	0,		0)
490 	OUT(HIL_PKT_CMD | HIL_CMD_DHR)
491 	IN(300000,		HILSEN_DHR2,	HILSEN_DHR2,	HILSEN_NEXT)
492 
493 	/* 14 HILSEN_IFC */
494 	OUT(HIL_PKT_CMD | HIL_CMD_IFC)
495 	EXPECT(HIL_PKT_CMD | HIL_CMD_IFC | HIL_ERR_INT,
496 	       20000,		HILSEN_DISC,	HILSEN_DHR2,	HILSEN_NEXT )
497 
498 	/* If devices are there, they weren't in PUP or other loopback mode.
499 	 * We're more concerned at this point with restoring operation
500 	 * to devices than discovering new ones, so we try to salvage
501 	 * the loop configuration by closing off the loop.
502 	 */
503 
504 	/* 16 HILSEN_HEAL0 */
505 	FUNC(hilse_dec_ddi, 0,	HILSEN_NEXT,	HILSEN_ACF,	0)
506 	FUNC(hilse_inc_ddi, 0,	HILSEN_NEXT,	0,		0)
507 
508 	/* 18 HILSEN_HEAL */
509 	OUT_LAST(HIL_CMD_ELB)
510 	EXPECT_LAST(HIL_CMD_ELB | HIL_ERR_INT,
511 		    20000,	HILSEN_REPOLL,	HILSEN_DSR,	HILSEN_NEXT)
512 	FUNC(hilse_dec_ddi, 0,	HILSEN_HEAL,	HILSEN_NEXT,	0)
513 
514 	/* 21 HILSEN_ACF */
515 	FUNC(hilse_init_lcv, 0,	HILSEN_NEXT,	HILSEN_DOZE,	0)
516 
517 	/* 22 HILSEN_ACF2 */
518 	FUNC(hilse_inc_lcv, 10,	HILSEN_NEXT,	HILSEN_START,	0)
519 	OUT(HIL_PKT_CMD | HIL_CMD_ACF | 1)
520 	IN(20000,		HILSEN_NEXT,	HILSEN_DSR,	HILSEN_NEXT)
521 
522 	/* 25 HILSEN_DISC0 */
523 	OUT_DISC(HIL_PKT_CMD | HIL_CMD_ELB)
524 	EXPECT_DISC(HIL_PKT_CMD | HIL_CMD_ELB | HIL_ERR_INT,
525 	       20000,		HILSEN_NEXT,	HILSEN_DSR,	HILSEN_DSR)
526 
527 	/* Only enter here if response just received */
528 	/* 27 HILSEN_DISC */
529 	OUT_DISC(HIL_PKT_CMD | HIL_CMD_IDD)
530 	EXPECT_DISC(HIL_PKT_CMD | HIL_CMD_IDD | HIL_ERR_INT,
531 	       20000,		HILSEN_NEXT,	HILSEN_DSR,	HILSEN_START)
532 	FUNC(hilse_inc_ddi,  0,	HILSEN_NEXT,	HILSEN_START,	0)
533 	FUNC(hilse_take_idd, 0,	HILSEN_MATCH,	HILSEN_IFCACF,	HILSEN_FOLLOW)
534 	OUT_LAST(HIL_PKT_CMD | HIL_CMD_RSC)
535 	EXPECT_LAST(HIL_PKT_CMD | HIL_CMD_RSC | HIL_ERR_INT,
536 	       30000,		HILSEN_NEXT,	HILSEN_DSR,	HILSEN_DSR)
537 	FUNC(hilse_take_rsc, 0,	HILSEN_MATCH,	0,		HILSEN_FOLLOW)
538 	OUT_LAST(HIL_PKT_CMD | HIL_CMD_EXD)
539 	EXPECT_LAST(HIL_PKT_CMD | HIL_CMD_EXD | HIL_ERR_INT,
540 	       30000,		HILSEN_NEXT,	HILSEN_DSR,	HILSEN_DSR)
541 	FUNC(hilse_take_exd, 0,	HILSEN_MATCH,	0,		HILSEN_FOLLOW)
542 	OUT_LAST(HIL_PKT_CMD | HIL_CMD_RNM)
543 	EXPECT_LAST(HIL_PKT_CMD | HIL_CMD_RNM | HIL_ERR_INT,
544 	       30000,		HILSEN_NEXT,	HILSEN_DSR,	HILSEN_DSR)
545 	FUNC(hilse_take_rnm, 0, HILSEN_MATCH,	0,		0)
546 
547 	/* 40 HILSEN_MATCH */
548 	FUNC(hilse_match, 0,	HILSEN_NEXT,	HILSEN_NEXT,	/* TODO */ 0)
549 
550 	/* 41 HILSEN_OPERATE */
551 	OUT(HIL_PKT_CMD | HIL_CMD_POL)
552 	EXPECT(HIL_PKT_CMD | HIL_CMD_POL | HIL_ERR_INT,
553 	       20000,		HILSEN_NEXT,	HILSEN_DSR,	HILSEN_NEXT)
554 	FUNC(hilse_operate, 0,	HILSEN_OPERATE,	HILSEN_IFC,	HILSEN_NEXT)
555 
556 	/* 44 HILSEN_PROBE */
557 	OUT_LAST(HIL_PKT_CMD | HIL_CMD_EPT)
558 	IN(10000,		HILSEN_DISC,	HILSEN_DSR,	HILSEN_NEXT)
559 	OUT_DISC(HIL_PKT_CMD | HIL_CMD_ELB)
560 	IN(10000,		HILSEN_DISC,	HILSEN_DSR,	HILSEN_NEXT)
561 	OUT(HIL_PKT_CMD | HIL_CMD_ACF | 1)
562 	IN(10000,		HILSEN_DISC0,	HILSEN_DSR,	HILSEN_NEXT)
563 	OUT_LAST(HIL_PKT_CMD | HIL_CMD_ELB)
564 	IN(10000,		HILSEN_OPERATE,	HILSEN_DSR,	HILSEN_DSR)
565 
566 	/* 52 HILSEN_DSR */
567 	FUNC(hilse_set_ddi, -1,	HILSEN_NEXT,	0,		0)
568 	OUT(HIL_PKT_CMD | HIL_CMD_DSR)
569 	IN(20000,		HILSEN_DHR,	HILSEN_DHR,	HILSEN_IFC)
570 
571 	/* 55 HILSEN_REPOLL */
572 	OUT(HIL_PKT_CMD | HIL_CMD_RPL)
573 	EXPECT(HIL_PKT_CMD | HIL_CMD_RPL | HIL_ERR_INT,
574 	       20000,		HILSEN_NEXT,	HILSEN_DSR,	HILSEN_NEXT)
575 	FUNC(hilse_operate, 1,	HILSEN_OPERATE,	HILSEN_IFC,	HILSEN_PROBE)
576 
577 	/* 58 HILSEN_IFCACF */
578 	OUT(HIL_PKT_CMD | HIL_CMD_IFC)
579 	EXPECT(HIL_PKT_CMD | HIL_CMD_IFC | HIL_ERR_INT,
580 	       20000,		HILSEN_ACF2,	HILSEN_DHR2,	HILSEN_HEAL)
581 
582 	/* 60 HILSEN_END */
583 };
584 
585 static inline void hilse_setup_input(hil_mlc *mlc, const struct hilse_node *node)
586 {
587 
588 	switch (node->act) {
589 	case HILSE_EXPECT_DISC:
590 		mlc->imatch = node->object.packet;
591 		mlc->imatch |= ((mlc->ddi + 2) << HIL_PKT_ADDR_SHIFT);
592 		break;
593 	case HILSE_EXPECT_LAST:
594 		mlc->imatch = node->object.packet;
595 		mlc->imatch |= ((mlc->ddi + 1) << HIL_PKT_ADDR_SHIFT);
596 		break;
597 	case HILSE_EXPECT:
598 		mlc->imatch = node->object.packet;
599 		break;
600 	case HILSE_IN:
601 		mlc->imatch = 0;
602 		break;
603 	default:
604 		BUG();
605 	}
606 	mlc->istarted = 1;
607 	mlc->intimeout = node->arg;
608 	do_gettimeofday(&(mlc->instart));
609 	mlc->icount = 15;
610 	memset(mlc->ipacket, 0, 16 * sizeof(hil_packet));
611 	BUG_ON(down_trylock(&mlc->isem));
612 }
613 
614 #ifdef HIL_MLC_DEBUG
615 static int doze;
616 static int seidx; /* For debug */
617 #endif
618 
619 static int hilse_donode(hil_mlc *mlc)
620 {
621 	const struct hilse_node *node;
622 	int nextidx = 0;
623 	int sched_long = 0;
624 	unsigned long flags;
625 
626 #ifdef HIL_MLC_DEBUG
627 	if (mlc->seidx && mlc->seidx != seidx &&
628 	    mlc->seidx != 41 && mlc->seidx != 42 && mlc->seidx != 43) {
629 		printk(KERN_DEBUG PREFIX "z%i \n {%i}", doze, mlc->seidx);
630 		doze = 0;
631 	}
632 
633 	seidx = mlc->seidx;
634 #endif
635 	node = hil_mlc_se + mlc->seidx;
636 
637 	switch (node->act) {
638 		int rc;
639 		hil_packet pack;
640 
641 	case HILSE_FUNC:
642 		BUG_ON(node->object.func == NULL);
643 		rc = node->object.func(mlc, node->arg);
644 		nextidx = (rc > 0) ? node->ugly :
645 			((rc < 0) ? node->bad : node->good);
646 		if (nextidx == HILSEN_FOLLOW)
647 			nextidx = rc;
648 		break;
649 
650 	case HILSE_EXPECT_LAST:
651 	case HILSE_EXPECT_DISC:
652 	case HILSE_EXPECT:
653 	case HILSE_IN:
654 		/* Already set up from previous HILSE_OUT_* */
655 		write_lock_irqsave(&mlc->lock, flags);
656 		rc = mlc->in(mlc, node->arg);
657 		if (rc == 2)  {
658 			nextidx = HILSEN_DOZE;
659 			sched_long = 1;
660 			write_unlock_irqrestore(&mlc->lock, flags);
661 			break;
662 		}
663 		if (rc == 1)
664 			nextidx = node->ugly;
665 		else if (rc == 0)
666 			nextidx = node->good;
667 		else
668 			nextidx = node->bad;
669 		mlc->istarted = 0;
670 		write_unlock_irqrestore(&mlc->lock, flags);
671 		break;
672 
673 	case HILSE_OUT_LAST:
674 		write_lock_irqsave(&mlc->lock, flags);
675 		pack = node->object.packet;
676 		pack |= ((mlc->ddi + 1) << HIL_PKT_ADDR_SHIFT);
677 		goto out;
678 
679 	case HILSE_OUT_DISC:
680 		write_lock_irqsave(&mlc->lock, flags);
681 		pack = node->object.packet;
682 		pack |= ((mlc->ddi + 2) << HIL_PKT_ADDR_SHIFT);
683 		goto out;
684 
685 	case HILSE_OUT:
686 		write_lock_irqsave(&mlc->lock, flags);
687 		pack = node->object.packet;
688 	out:
689 		if (!mlc->istarted) {
690 			/* Prepare to receive input */
691 			if ((node + 1)->act & HILSE_IN)
692 				hilse_setup_input(mlc, node + 1);
693 		}
694 
695 		write_unlock_irqrestore(&mlc->lock, flags);
696 
697 		if (down_trylock(&mlc->osem)) {
698 			nextidx = HILSEN_DOZE;
699 			break;
700 		}
701 		up(&mlc->osem);
702 
703 		write_lock_irqsave(&mlc->lock, flags);
704 		if (!mlc->ostarted) {
705 			mlc->ostarted = 1;
706 			mlc->opacket = pack;
707 			mlc->out(mlc);
708 			nextidx = HILSEN_DOZE;
709 			write_unlock_irqrestore(&mlc->lock, flags);
710 			break;
711 		}
712 		mlc->ostarted = 0;
713 		do_gettimeofday(&(mlc->instart));
714 		write_unlock_irqrestore(&mlc->lock, flags);
715 		nextidx = HILSEN_NEXT;
716 		break;
717 
718 	case HILSE_CTS:
719 		write_lock_irqsave(&mlc->lock, flags);
720 		nextidx = mlc->cts(mlc) ? node->bad : node->good;
721 		write_unlock_irqrestore(&mlc->lock, flags);
722 		break;
723 
724 	default:
725 		BUG();
726 	}
727 
728 #ifdef HIL_MLC_DEBUG
729 	if (nextidx == HILSEN_DOZE)
730 		doze++;
731 #endif
732 
733 	while (nextidx & HILSEN_SCHED) {
734 		struct timeval tv;
735 
736 		if (!sched_long)
737 			goto sched;
738 
739 		do_gettimeofday(&tv);
740 		tv.tv_usec += USEC_PER_SEC * (tv.tv_sec - mlc->instart.tv_sec);
741 		tv.tv_usec -= mlc->instart.tv_usec;
742 		if (tv.tv_usec >= mlc->intimeout) goto sched;
743 		tv.tv_usec = (mlc->intimeout - tv.tv_usec) * HZ / USEC_PER_SEC;
744 		if (!tv.tv_usec) goto sched;
745 		mod_timer(&hil_mlcs_kicker, jiffies + tv.tv_usec);
746 		break;
747 	sched:
748 		tasklet_schedule(&hil_mlcs_tasklet);
749 		break;
750 	}
751 
752 	if (nextidx & HILSEN_DOWN)
753 		mlc->seidx += nextidx & HILSEN_MASK;
754 	else if (nextidx & HILSEN_UP)
755 		mlc->seidx -= nextidx & HILSEN_MASK;
756 	else
757 		mlc->seidx = nextidx & HILSEN_MASK;
758 
759 	if (nextidx & HILSEN_BREAK)
760 		return 1;
761 
762 	return 0;
763 }
764 
765 /******************** tasklet context functions **************************/
766 static void hil_mlcs_process(unsigned long unused)
767 {
768 	struct list_head *tmp;
769 
770 	read_lock(&hil_mlcs_lock);
771 	list_for_each(tmp, &hil_mlcs) {
772 		struct hil_mlc *mlc = list_entry(tmp, hil_mlc, list);
773 		while (hilse_donode(mlc) == 0) {
774 #ifdef HIL_MLC_DEBUG
775 			if (mlc->seidx != 41 &&
776 			    mlc->seidx != 42 &&
777 			    mlc->seidx != 43)
778 				printk(KERN_DEBUG PREFIX " + ");
779 #endif
780 		}
781 	}
782 	read_unlock(&hil_mlcs_lock);
783 }
784 
785 /************************* Keepalive timer task *********************/
786 
787 static void hil_mlcs_timer(unsigned long data)
788 {
789 	hil_mlcs_probe = 1;
790 	tasklet_schedule(&hil_mlcs_tasklet);
791 	/* Re-insert the periodic task. */
792 	if (!timer_pending(&hil_mlcs_kicker))
793 		mod_timer(&hil_mlcs_kicker, jiffies + HZ);
794 }
795 
796 /******************** user/kernel context functions **********************/
797 
798 static int hil_mlc_serio_write(struct serio *serio, unsigned char c)
799 {
800 	struct hil_mlc_serio_map *map;
801 	struct hil_mlc *mlc;
802 	struct serio_driver *drv;
803 	uint8_t *idx, *last;
804 
805 	map = serio->port_data;
806 	BUG_ON(map == NULL);
807 
808 	mlc = map->mlc;
809 	BUG_ON(mlc == NULL);
810 
811 	mlc->serio_opacket[map->didx] |=
812 		((hil_packet)c) << (8 * (3 - mlc->serio_oidx[map->didx]));
813 
814 	if (mlc->serio_oidx[map->didx] >= 3) {
815 		/* for now only commands */
816 		if (!(mlc->serio_opacket[map->didx] & HIL_PKT_CMD))
817 			return -EIO;
818 		switch (mlc->serio_opacket[map->didx] & HIL_PKT_DATA_MASK) {
819 		case HIL_CMD_IDD:
820 			idx = mlc->di[map->didx].idd;
821 			goto emu;
822 		case HIL_CMD_RSC:
823 			idx = mlc->di[map->didx].rsc;
824 			goto emu;
825 		case HIL_CMD_EXD:
826 			idx = mlc->di[map->didx].exd;
827 			goto emu;
828 		case HIL_CMD_RNM:
829 			idx = mlc->di[map->didx].rnm;
830 			goto emu;
831 		default:
832 			break;
833 		}
834 		mlc->serio_oidx[map->didx] = 0;
835 		mlc->serio_opacket[map->didx] = 0;
836 	}
837 
838 	mlc->serio_oidx[map->didx]++;
839 	return -EIO;
840  emu:
841 	drv = serio->drv;
842 	BUG_ON(drv == NULL);
843 
844 	last = idx + 15;
845 	while ((last != idx) && (*last == 0))
846 		last--;
847 
848 	while (idx != last) {
849 		drv->interrupt(serio, 0, 0);
850 		drv->interrupt(serio, HIL_ERR_INT >> 16, 0);
851 		drv->interrupt(serio, 0, 0);
852 		drv->interrupt(serio, *idx, 0);
853 		idx++;
854 	}
855 	drv->interrupt(serio, 0, 0);
856 	drv->interrupt(serio, HIL_ERR_INT >> 16, 0);
857 	drv->interrupt(serio, HIL_PKT_CMD >> 8, 0);
858 	drv->interrupt(serio, *idx, 0);
859 
860 	mlc->serio_oidx[map->didx] = 0;
861 	mlc->serio_opacket[map->didx] = 0;
862 
863 	return 0;
864 }
865 
866 static int hil_mlc_serio_open(struct serio *serio)
867 {
868 	struct hil_mlc_serio_map *map;
869 	struct hil_mlc *mlc;
870 
871 	if (serio_get_drvdata(serio) != NULL)
872 		return -EBUSY;
873 
874 	map = serio->port_data;
875 	BUG_ON(map == NULL);
876 
877 	mlc = map->mlc;
878 	BUG_ON(mlc == NULL);
879 
880 	return 0;
881 }
882 
883 static void hil_mlc_serio_close(struct serio *serio)
884 {
885 	struct hil_mlc_serio_map *map;
886 	struct hil_mlc *mlc;
887 
888 	map = serio->port_data;
889 	BUG_ON(map == NULL);
890 
891 	mlc = map->mlc;
892 	BUG_ON(mlc == NULL);
893 
894 	serio_set_drvdata(serio, NULL);
895 	serio->drv = NULL;
896 	/* TODO wake up interruptable */
897 }
898 
899 static const struct serio_device_id hil_mlc_serio_id = {
900 	.type = SERIO_HIL_MLC,
901 	.proto = SERIO_HIL,
902 	.extra = SERIO_ANY,
903 	.id = SERIO_ANY,
904 };
905 
906 int hil_mlc_register(hil_mlc *mlc)
907 {
908 	int i;
909 	unsigned long flags;
910 
911 	BUG_ON(mlc == NULL);
912 
913 	mlc->istarted = 0;
914 	mlc->ostarted = 0;
915 
916 	rwlock_init(&mlc->lock);
917 	sema_init(&mlc->osem, 1);
918 
919 	sema_init(&mlc->isem, 1);
920 	mlc->icount = -1;
921 	mlc->imatch = 0;
922 
923 	mlc->opercnt = 0;
924 
925 	sema_init(&(mlc->csem), 0);
926 
927 	hil_mlc_clear_di_scratch(mlc);
928 	hil_mlc_clear_di_map(mlc, 0);
929 	for (i = 0; i < HIL_MLC_DEVMEM; i++) {
930 		struct serio *mlc_serio;
931 		hil_mlc_copy_di_scratch(mlc, i);
932 		mlc_serio = kzalloc(sizeof(*mlc_serio), GFP_KERNEL);
933 		mlc->serio[i] = mlc_serio;
934 		if (!mlc->serio[i]) {
935 			for (; i >= 0; i--)
936 				kfree(mlc->serio[i]);
937 			return -ENOMEM;
938 		}
939 		snprintf(mlc_serio->name, sizeof(mlc_serio->name)-1, "HIL_SERIO%d", i);
940 		snprintf(mlc_serio->phys, sizeof(mlc_serio->phys)-1, "HIL%d", i);
941 		mlc_serio->id			= hil_mlc_serio_id;
942 		mlc_serio->id.id		= i; /* HIL port no. */
943 		mlc_serio->write		= hil_mlc_serio_write;
944 		mlc_serio->open			= hil_mlc_serio_open;
945 		mlc_serio->close		= hil_mlc_serio_close;
946 		mlc_serio->port_data		= &(mlc->serio_map[i]);
947 		mlc->serio_map[i].mlc		= mlc;
948 		mlc->serio_map[i].didx		= i;
949 		mlc->serio_map[i].di_revmap	= -1;
950 		mlc->serio_opacket[i]		= 0;
951 		mlc->serio_oidx[i]		= 0;
952 		serio_register_port(mlc_serio);
953 	}
954 
955 	mlc->tasklet = &hil_mlcs_tasklet;
956 
957 	write_lock_irqsave(&hil_mlcs_lock, flags);
958 	list_add_tail(&mlc->list, &hil_mlcs);
959 	mlc->seidx = HILSEN_START;
960 	write_unlock_irqrestore(&hil_mlcs_lock, flags);
961 
962 	tasklet_schedule(&hil_mlcs_tasklet);
963 	return 0;
964 }
965 
966 int hil_mlc_unregister(hil_mlc *mlc)
967 {
968 	struct list_head *tmp;
969 	unsigned long flags;
970 	int i;
971 
972 	BUG_ON(mlc == NULL);
973 
974 	write_lock_irqsave(&hil_mlcs_lock, flags);
975 	list_for_each(tmp, &hil_mlcs)
976 		if (list_entry(tmp, hil_mlc, list) == mlc)
977 			goto found;
978 
979 	/* not found in list */
980 	write_unlock_irqrestore(&hil_mlcs_lock, flags);
981 	tasklet_schedule(&hil_mlcs_tasklet);
982 	return -ENODEV;
983 
984  found:
985 	list_del(tmp);
986 	write_unlock_irqrestore(&hil_mlcs_lock, flags);
987 
988 	for (i = 0; i < HIL_MLC_DEVMEM; i++) {
989 		serio_unregister_port(mlc->serio[i]);
990 		mlc->serio[i] = NULL;
991 	}
992 
993 	tasklet_schedule(&hil_mlcs_tasklet);
994 	return 0;
995 }
996 
997 /**************************** Module interface *************************/
998 
999 static int __init hil_mlc_init(void)
1000 {
1001 	setup_timer(&hil_mlcs_kicker, &hil_mlcs_timer, 0);
1002 	mod_timer(&hil_mlcs_kicker, jiffies + HZ);
1003 
1004 	tasklet_enable(&hil_mlcs_tasklet);
1005 
1006 	return 0;
1007 }
1008 
1009 static void __exit hil_mlc_exit(void)
1010 {
1011 	del_timer_sync(&hil_mlcs_kicker);
1012 	tasklet_kill(&hil_mlcs_tasklet);
1013 }
1014 
1015 module_init(hil_mlc_init);
1016 module_exit(hil_mlc_exit);
1017