xref: /openbmc/linux/drivers/macintosh/via-cuda.c (revision dea54fba)
1 /*
2  * Device driver for the Cuda and Egret system controllers found on PowerMacs
3  * and 68k Macs.
4  *
5  * The Cuda or Egret is a 6805 microcontroller interfaced to the 6522 VIA.
6  * This MCU controls system power, Parameter RAM, Real Time Clock and the
7  * Apple Desktop Bus (ADB) that connects to the keyboard and mouse.
8  *
9  * Copyright (C) 1996 Paul Mackerras.
10  */
11 #include <stdarg.h>
12 #include <linux/types.h>
13 #include <linux/errno.h>
14 #include <linux/kernel.h>
15 #include <linux/delay.h>
16 #include <linux/adb.h>
17 #include <linux/cuda.h>
18 #include <linux/spinlock.h>
19 #include <linux/interrupt.h>
20 #ifdef CONFIG_PPC
21 #include <asm/prom.h>
22 #include <asm/machdep.h>
23 #else
24 #include <asm/macintosh.h>
25 #include <asm/macints.h>
26 #include <asm/mac_via.h>
27 #endif
28 #include <asm/io.h>
29 #include <linux/init.h>
30 
31 static volatile unsigned char __iomem *via;
32 static DEFINE_SPINLOCK(cuda_lock);
33 
34 /* VIA registers - spaced 0x200 bytes apart */
35 #define RS		0x200		/* skip between registers */
36 #define B		0		/* B-side data */
37 #define A		RS		/* A-side data */
38 #define DIRB		(2*RS)		/* B-side direction (1=output) */
39 #define DIRA		(3*RS)		/* A-side direction (1=output) */
40 #define T1CL		(4*RS)		/* Timer 1 ctr/latch (low 8 bits) */
41 #define T1CH		(5*RS)		/* Timer 1 counter (high 8 bits) */
42 #define T1LL		(6*RS)		/* Timer 1 latch (low 8 bits) */
43 #define T1LH		(7*RS)		/* Timer 1 latch (high 8 bits) */
44 #define T2CL		(8*RS)		/* Timer 2 ctr/latch (low 8 bits) */
45 #define T2CH		(9*RS)		/* Timer 2 counter (high 8 bits) */
46 #define SR		(10*RS)		/* Shift register */
47 #define ACR		(11*RS)		/* Auxiliary control register */
48 #define PCR		(12*RS)		/* Peripheral control register */
49 #define IFR		(13*RS)		/* Interrupt flag register */
50 #define IER		(14*RS)		/* Interrupt enable register */
51 #define ANH		(15*RS)		/* A-side data, no handshake */
52 
53 /*
54  * When the Cuda design replaced the Egret, some signal names and
55  * logic sense changed. They all serve the same purposes, however.
56  *
57  *   VIA pin       |  Egret pin
58  * ----------------+------------------------------------------
59  *   PB3 (input)   |  Transceiver session   (active low)
60  *   PB4 (output)  |  VIA full              (active high)
61  *   PB5 (output)  |  System session        (active high)
62  *
63  *   VIA pin       |  Cuda pin
64  * ----------------+------------------------------------------
65  *   PB3 (input)   |  Transfer request      (active low)
66  *   PB4 (output)  |  Byte acknowledge      (active low)
67  *   PB5 (output)  |  Transfer in progress  (active low)
68  */
69 
70 /* Bits in Port B data register */
71 #define TREQ		0x08		/* Transfer request */
72 #define TACK		0x10		/* Transfer acknowledge */
73 #define TIP		0x20		/* Transfer in progress */
74 
75 /* Bits in ACR */
76 #define SR_CTRL		0x1c		/* Shift register control bits */
77 #define SR_EXT		0x0c		/* Shift on external clock */
78 #define SR_OUT		0x10		/* Shift out if 1 */
79 
80 /* Bits in IFR and IER */
81 #define IER_SET		0x80		/* set bits in IER */
82 #define IER_CLR		0		/* clear bits in IER */
83 #define SR_INT		0x04		/* Shift register full/empty */
84 
85 /* Duration of byte acknowledgement pulse (us) */
86 #define EGRET_TACK_ASSERTED_DELAY	300
87 #define EGRET_TACK_NEGATED_DELAY	400
88 
89 /* Interval from interrupt to start of session (us) */
90 #define EGRET_SESSION_DELAY		450
91 
92 #ifdef CONFIG_PPC
93 #define mcu_is_egret	false
94 #else
95 static bool mcu_is_egret;
96 #endif
97 
98 static inline bool TREQ_asserted(u8 portb)
99 {
100 	return !(portb & TREQ);
101 }
102 
103 static inline void assert_TIP(void)
104 {
105 	if (mcu_is_egret) {
106 		udelay(EGRET_SESSION_DELAY);
107 		out_8(&via[B], in_8(&via[B]) | TIP);
108 	} else
109 		out_8(&via[B], in_8(&via[B]) & ~TIP);
110 }
111 
112 static inline void assert_TIP_and_TACK(void)
113 {
114 	if (mcu_is_egret) {
115 		udelay(EGRET_SESSION_DELAY);
116 		out_8(&via[B], in_8(&via[B]) | TIP | TACK);
117 	} else
118 		out_8(&via[B], in_8(&via[B]) & ~(TIP | TACK));
119 }
120 
121 static inline void assert_TACK(void)
122 {
123 	if (mcu_is_egret) {
124 		udelay(EGRET_TACK_NEGATED_DELAY);
125 		out_8(&via[B], in_8(&via[B]) | TACK);
126 	} else
127 		out_8(&via[B], in_8(&via[B]) & ~TACK);
128 }
129 
130 static inline void toggle_TACK(void)
131 {
132 	out_8(&via[B], in_8(&via[B]) ^ TACK);
133 }
134 
135 static inline void negate_TACK(void)
136 {
137 	if (mcu_is_egret) {
138 		udelay(EGRET_TACK_ASSERTED_DELAY);
139 		out_8(&via[B], in_8(&via[B]) & ~TACK);
140 	} else
141 		out_8(&via[B], in_8(&via[B]) | TACK);
142 }
143 
144 static inline void negate_TIP_and_TACK(void)
145 {
146 	if (mcu_is_egret) {
147 		udelay(EGRET_TACK_ASSERTED_DELAY);
148 		out_8(&via[B], in_8(&via[B]) & ~(TIP | TACK));
149 	} else
150 		out_8(&via[B], in_8(&via[B]) | TIP | TACK);
151 }
152 
153 static enum cuda_state {
154     idle,
155     sent_first_byte,
156     sending,
157     reading,
158     read_done,
159     awaiting_reply
160 } cuda_state;
161 
162 static struct adb_request *current_req;
163 static struct adb_request *last_req;
164 static unsigned char cuda_rbuf[16];
165 static unsigned char *reply_ptr;
166 static int reading_reply;
167 static int data_index;
168 static int cuda_irq;
169 #ifdef CONFIG_PPC
170 static struct device_node *vias;
171 #endif
172 static int cuda_fully_inited;
173 
174 #ifdef CONFIG_ADB
175 static int cuda_probe(void);
176 static int cuda_send_request(struct adb_request *req, int sync);
177 static int cuda_adb_autopoll(int devs);
178 static int cuda_reset_adb_bus(void);
179 #endif /* CONFIG_ADB */
180 
181 static int cuda_init_via(void);
182 static void cuda_start(void);
183 static irqreturn_t cuda_interrupt(int irq, void *arg);
184 static void cuda_input(unsigned char *buf, int nb);
185 void cuda_poll(void);
186 static int cuda_write(struct adb_request *req);
187 
188 int cuda_request(struct adb_request *req,
189 		 void (*done)(struct adb_request *), int nbytes, ...);
190 
191 #ifdef CONFIG_ADB
192 struct adb_driver via_cuda_driver = {
193 	.name         = "CUDA",
194 	.probe        = cuda_probe,
195 	.send_request = cuda_send_request,
196 	.autopoll     = cuda_adb_autopoll,
197 	.poll         = cuda_poll,
198 	.reset_bus    = cuda_reset_adb_bus,
199 };
200 #endif /* CONFIG_ADB */
201 
202 #ifdef CONFIG_MAC
203 int __init find_via_cuda(void)
204 {
205     struct adb_request req;
206     int err;
207 
208     if (macintosh_config->adb_type != MAC_ADB_CUDA &&
209         macintosh_config->adb_type != MAC_ADB_EGRET)
210 	return 0;
211 
212     via = via1;
213     cuda_state = idle;
214     mcu_is_egret = macintosh_config->adb_type == MAC_ADB_EGRET;
215 
216     err = cuda_init_via();
217     if (err) {
218 	printk(KERN_ERR "cuda_init_via() failed\n");
219 	via = NULL;
220 	return 0;
221     }
222 
223     /* enable autopoll */
224     cuda_request(&req, NULL, 3, CUDA_PACKET, CUDA_AUTOPOLL, 1);
225     while (!req.complete)
226 	cuda_poll();
227 
228     return 1;
229 }
230 #else
231 int __init find_via_cuda(void)
232 {
233     struct adb_request req;
234     phys_addr_t taddr;
235     const u32 *reg;
236     int err;
237 
238     if (vias != 0)
239 	return 1;
240     vias = of_find_node_by_name(NULL, "via-cuda");
241     if (vias == 0)
242 	return 0;
243 
244     reg = of_get_property(vias, "reg", NULL);
245     if (reg == NULL) {
246 	    printk(KERN_ERR "via-cuda: No \"reg\" property !\n");
247 	    goto fail;
248     }
249     taddr = of_translate_address(vias, reg);
250     if (taddr == 0) {
251 	    printk(KERN_ERR "via-cuda: Can't translate address !\n");
252 	    goto fail;
253     }
254     via = ioremap(taddr, 0x2000);
255     if (via == NULL) {
256 	    printk(KERN_ERR "via-cuda: Can't map address !\n");
257 	    goto fail;
258     }
259 
260     cuda_state = idle;
261     sys_ctrler = SYS_CTRLER_CUDA;
262 
263     err = cuda_init_via();
264     if (err) {
265 	printk(KERN_ERR "cuda_init_via() failed\n");
266 	via = NULL;
267 	return 0;
268     }
269 
270     /* Clear and enable interrupts, but only on PPC. On 68K it's done  */
271     /* for us by the main VIA driver in arch/m68k/mac/via.c        */
272 
273     out_8(&via[IFR], 0x7f);	/* clear interrupts by writing 1s */
274     out_8(&via[IER], IER_SET|SR_INT); /* enable interrupt from SR */
275 
276     /* enable autopoll */
277     cuda_request(&req, NULL, 3, CUDA_PACKET, CUDA_AUTOPOLL, 1);
278     while (!req.complete)
279 	cuda_poll();
280 
281     return 1;
282 
283  fail:
284     of_node_put(vias);
285     vias = NULL;
286     return 0;
287 }
288 #endif /* !defined CONFIG_MAC */
289 
290 static int __init via_cuda_start(void)
291 {
292     if (via == NULL)
293 	return -ENODEV;
294 
295 #ifdef CONFIG_MAC
296     cuda_irq = IRQ_MAC_ADB;
297 #else
298     cuda_irq = irq_of_parse_and_map(vias, 0);
299     if (!cuda_irq) {
300 	printk(KERN_ERR "via-cuda: can't map interrupts for %s\n",
301 	       vias->full_name);
302 	return -ENODEV;
303     }
304 #endif
305 
306     if (request_irq(cuda_irq, cuda_interrupt, 0, "ADB", cuda_interrupt)) {
307 	printk(KERN_ERR "via-cuda: can't request irq %d\n", cuda_irq);
308 	return -EAGAIN;
309     }
310 
311     pr_info("Macintosh Cuda and Egret driver.\n");
312 
313     cuda_fully_inited = 1;
314     return 0;
315 }
316 
317 device_initcall(via_cuda_start);
318 
319 #ifdef CONFIG_ADB
320 static int
321 cuda_probe(void)
322 {
323 #ifdef CONFIG_PPC
324     if (sys_ctrler != SYS_CTRLER_CUDA)
325 	return -ENODEV;
326 #else
327     if (macintosh_config->adb_type != MAC_ADB_CUDA &&
328         macintosh_config->adb_type != MAC_ADB_EGRET)
329 	return -ENODEV;
330 #endif
331     if (via == NULL)
332 	return -ENODEV;
333     return 0;
334 }
335 #endif /* CONFIG_ADB */
336 
337 static int __init sync_egret(void)
338 {
339 	if (TREQ_asserted(in_8(&via[B]))) {
340 		/* Complete the inbound transfer */
341 		assert_TIP_and_TACK();
342 		while (1) {
343 			negate_TACK();
344 			mdelay(1);
345 			(void)in_8(&via[SR]);
346 			assert_TACK();
347 			if (!TREQ_asserted(in_8(&via[B])))
348 				break;
349 		}
350 		negate_TIP_and_TACK();
351 	} else if (in_8(&via[B]) & TIP) {
352 		/* Terminate the outbound transfer */
353 		negate_TACK();
354 		assert_TACK();
355 		mdelay(1);
356 		negate_TIP_and_TACK();
357 	}
358 	/* Clear shift register interrupt */
359 	if (in_8(&via[IFR]) & SR_INT)
360 		(void)in_8(&via[SR]);
361 	return 0;
362 }
363 
364 #define WAIT_FOR(cond, what)					\
365     do {                                                        \
366     	int x;							\
367 	for (x = 1000; !(cond); --x) {				\
368 	    if (x == 0) {					\
369 		pr_err("Timeout waiting for " what "\n");	\
370 		return -ENXIO;					\
371 	    }							\
372 	    udelay(100);					\
373 	}							\
374     } while (0)
375 
376 static int
377 __init cuda_init_via(void)
378 {
379 #ifdef CONFIG_PPC
380     out_8(&via[IER], 0x7f);					/* disable interrupts from VIA */
381     (void)in_8(&via[IER]);
382 #else
383     out_8(&via[IER], SR_INT);					/* disable SR interrupt from VIA */
384 #endif
385 
386     out_8(&via[DIRB], (in_8(&via[DIRB]) | TACK | TIP) & ~TREQ);	/* TACK & TIP out */
387     out_8(&via[ACR], (in_8(&via[ACR]) & ~SR_CTRL) | SR_EXT);	/* SR data in */
388     (void)in_8(&via[SR]);					/* clear any left-over data */
389 
390     if (mcu_is_egret)
391 	return sync_egret();
392 
393     negate_TIP_and_TACK();
394 
395     /* delay 4ms and then clear any pending interrupt */
396     mdelay(4);
397     (void)in_8(&via[SR]);
398     out_8(&via[IFR], SR_INT);
399 
400     /* sync with the CUDA - assert TACK without TIP */
401     assert_TACK();
402 
403     /* wait for the CUDA to assert TREQ in response */
404     WAIT_FOR(TREQ_asserted(in_8(&via[B])), "CUDA response to sync");
405 
406     /* wait for the interrupt and then clear it */
407     WAIT_FOR(in_8(&via[IFR]) & SR_INT, "CUDA response to sync (2)");
408     (void)in_8(&via[SR]);
409     out_8(&via[IFR], SR_INT);
410 
411     /* finish the sync by negating TACK */
412     negate_TACK();
413 
414     /* wait for the CUDA to negate TREQ and the corresponding interrupt */
415     WAIT_FOR(!TREQ_asserted(in_8(&via[B])), "CUDA response to sync (3)");
416     WAIT_FOR(in_8(&via[IFR]) & SR_INT, "CUDA response to sync (4)");
417     (void)in_8(&via[SR]);
418     out_8(&via[IFR], SR_INT);
419 
420     return 0;
421 }
422 
423 #ifdef CONFIG_ADB
424 /* Send an ADB command */
425 static int
426 cuda_send_request(struct adb_request *req, int sync)
427 {
428     int i;
429 
430     if ((via == NULL) || !cuda_fully_inited) {
431 	req->complete = 1;
432 	return -ENXIO;
433     }
434 
435     req->reply_expected = 1;
436 
437     i = cuda_write(req);
438     if (i)
439 	return i;
440 
441     if (sync) {
442 	while (!req->complete)
443 	    cuda_poll();
444     }
445     return 0;
446 }
447 
448 
449 /* Enable/disable autopolling */
450 static int
451 cuda_adb_autopoll(int devs)
452 {
453     struct adb_request req;
454 
455     if ((via == NULL) || !cuda_fully_inited)
456 	return -ENXIO;
457 
458     cuda_request(&req, NULL, 3, CUDA_PACKET, CUDA_AUTOPOLL, (devs? 1: 0));
459     while (!req.complete)
460 	cuda_poll();
461     return 0;
462 }
463 
464 /* Reset adb bus - how do we do this?? */
465 static int
466 cuda_reset_adb_bus(void)
467 {
468     struct adb_request req;
469 
470     if ((via == NULL) || !cuda_fully_inited)
471 	return -ENXIO;
472 
473     cuda_request(&req, NULL, 2, ADB_PACKET, 0);		/* maybe? */
474     while (!req.complete)
475 	cuda_poll();
476     return 0;
477 }
478 #endif /* CONFIG_ADB */
479 
480 /* Construct and send a cuda request */
481 int
482 cuda_request(struct adb_request *req, void (*done)(struct adb_request *),
483 	     int nbytes, ...)
484 {
485     va_list list;
486     int i;
487 
488     if (via == NULL) {
489 	req->complete = 1;
490 	return -ENXIO;
491     }
492 
493     req->nbytes = nbytes;
494     req->done = done;
495     va_start(list, nbytes);
496     for (i = 0; i < nbytes; ++i)
497 	req->data[i] = va_arg(list, int);
498     va_end(list);
499     req->reply_expected = 1;
500     return cuda_write(req);
501 }
502 EXPORT_SYMBOL(cuda_request);
503 
504 static int
505 cuda_write(struct adb_request *req)
506 {
507     unsigned long flags;
508 
509     if (req->nbytes < 2 || req->data[0] > CUDA_PACKET) {
510 	req->complete = 1;
511 	return -EINVAL;
512     }
513     req->next = NULL;
514     req->sent = 0;
515     req->complete = 0;
516     req->reply_len = 0;
517 
518     spin_lock_irqsave(&cuda_lock, flags);
519     if (current_req != 0) {
520 	last_req->next = req;
521 	last_req = req;
522     } else {
523 	current_req = req;
524 	last_req = req;
525 	if (cuda_state == idle)
526 	    cuda_start();
527     }
528     spin_unlock_irqrestore(&cuda_lock, flags);
529 
530     return 0;
531 }
532 
533 static void
534 cuda_start(void)
535 {
536     /* assert cuda_state == idle */
537     if (current_req == NULL)
538 	return;
539     data_index = 0;
540     if (TREQ_asserted(in_8(&via[B])))
541 	return;			/* a byte is coming in from the CUDA */
542 
543     /* set the shift register to shift out and send a byte */
544     out_8(&via[ACR], in_8(&via[ACR]) | SR_OUT);
545     out_8(&via[SR], current_req->data[data_index++]);
546     if (mcu_is_egret)
547 	assert_TIP_and_TACK();
548     else
549 	assert_TIP();
550     cuda_state = sent_first_byte;
551 }
552 
553 void
554 cuda_poll(void)
555 {
556 	cuda_interrupt(0, NULL);
557 }
558 EXPORT_SYMBOL(cuda_poll);
559 
560 #define ARRAY_FULL(a, p)	((p) - (a) == ARRAY_SIZE(a))
561 
562 static irqreturn_t
563 cuda_interrupt(int irq, void *arg)
564 {
565     unsigned long flags;
566     u8 status;
567     struct adb_request *req = NULL;
568     unsigned char ibuf[16];
569     int ibuf_len = 0;
570     int complete = 0;
571 
572     spin_lock_irqsave(&cuda_lock, flags);
573 
574     /* On powermacs, this handler is registered for the VIA IRQ. But they use
575      * just the shift register IRQ -- other VIA interrupt sources are disabled.
576      * On m68k macs, the VIA IRQ sources are dispatched individually. Unless
577      * we are polling, the shift register IRQ flag has already been cleared.
578      */
579 
580 #ifdef CONFIG_MAC
581     if (!arg)
582 #endif
583     {
584         if ((in_8(&via[IFR]) & SR_INT) == 0) {
585             spin_unlock_irqrestore(&cuda_lock, flags);
586             return IRQ_NONE;
587         } else {
588             out_8(&via[IFR], SR_INT);
589         }
590     }
591 
592     status = in_8(&via[B]) & (TIP | TACK | TREQ);
593 
594     switch (cuda_state) {
595     case idle:
596 	/* System controller has unsolicited data for us */
597 	(void)in_8(&via[SR]);
598 idle_state:
599 	assert_TIP();
600 	cuda_state = reading;
601 	reply_ptr = cuda_rbuf;
602 	reading_reply = 0;
603 	break;
604 
605     case awaiting_reply:
606 	/* System controller has reply data for us */
607 	(void)in_8(&via[SR]);
608 	assert_TIP();
609 	cuda_state = reading;
610 	reply_ptr = current_req->reply;
611 	reading_reply = 1;
612 	break;
613 
614     case sent_first_byte:
615 	if (TREQ_asserted(status)) {
616 	    /* collision */
617 	    out_8(&via[ACR], in_8(&via[ACR]) & ~SR_OUT);
618 	    (void)in_8(&via[SR]);
619 	    negate_TIP_and_TACK();
620 	    cuda_state = idle;
621 	    /* Egret does not raise an "aborted" interrupt */
622 	    if (mcu_is_egret)
623 		goto idle_state;
624 	} else {
625 	    out_8(&via[SR], current_req->data[data_index++]);
626 	    toggle_TACK();
627 	    if (mcu_is_egret)
628 		assert_TACK();
629 	    cuda_state = sending;
630 	}
631 	break;
632 
633     case sending:
634 	req = current_req;
635 	if (data_index >= req->nbytes) {
636 	    out_8(&via[ACR], in_8(&via[ACR]) & ~SR_OUT);
637 	    (void)in_8(&via[SR]);
638 	    negate_TIP_and_TACK();
639 	    req->sent = 1;
640 	    if (req->reply_expected) {
641 		cuda_state = awaiting_reply;
642 	    } else {
643 		current_req = req->next;
644 		complete = 1;
645 		/* not sure about this */
646 		cuda_state = idle;
647 		cuda_start();
648 	    }
649 	} else {
650 	    out_8(&via[SR], req->data[data_index++]);
651 	    toggle_TACK();
652 	    if (mcu_is_egret)
653 		assert_TACK();
654 	}
655 	break;
656 
657     case reading:
658 	if (reading_reply ? ARRAY_FULL(current_req->reply, reply_ptr)
659 	                  : ARRAY_FULL(cuda_rbuf, reply_ptr))
660 	    (void)in_8(&via[SR]);
661 	else
662 	    *reply_ptr++ = in_8(&via[SR]);
663 	if (!TREQ_asserted(status)) {
664 	    if (mcu_is_egret)
665 		assert_TACK();
666 	    /* that's all folks */
667 	    negate_TIP_and_TACK();
668 	    cuda_state = read_done;
669 	    /* Egret does not raise a "read done" interrupt */
670 	    if (mcu_is_egret)
671 		goto read_done_state;
672 	} else {
673 	    toggle_TACK();
674 	    if (mcu_is_egret)
675 		negate_TACK();
676 	}
677 	break;
678 
679     case read_done:
680 	(void)in_8(&via[SR]);
681 read_done_state:
682 	if (reading_reply) {
683 	    req = current_req;
684 	    req->reply_len = reply_ptr - req->reply;
685 	    if (req->data[0] == ADB_PACKET) {
686 		/* Have to adjust the reply from ADB commands */
687 		if (req->reply_len <= 2 || (req->reply[1] & 2) != 0) {
688 		    /* the 0x2 bit indicates no response */
689 		    req->reply_len = 0;
690 		} else {
691 		    /* leave just the command and result bytes in the reply */
692 		    req->reply_len -= 2;
693 		    memmove(req->reply, req->reply + 2, req->reply_len);
694 		}
695 	    }
696 	    current_req = req->next;
697 	    complete = 1;
698 	    reading_reply = 0;
699 	} else {
700 	    /* This is tricky. We must break the spinlock to call
701 	     * cuda_input. However, doing so means we might get
702 	     * re-entered from another CPU getting an interrupt
703 	     * or calling cuda_poll(). I ended up using the stack
704 	     * (it's only for 16 bytes) and moving the actual
705 	     * call to cuda_input to outside of the lock.
706 	     */
707 	    ibuf_len = reply_ptr - cuda_rbuf;
708 	    memcpy(ibuf, cuda_rbuf, ibuf_len);
709 	}
710 	reply_ptr = cuda_rbuf;
711 	cuda_state = idle;
712 	cuda_start();
713 	if (cuda_state == idle && TREQ_asserted(in_8(&via[B]))) {
714 	    assert_TIP();
715 	    cuda_state = reading;
716 	}
717 	break;
718 
719     default:
720 	pr_err("cuda_interrupt: unknown cuda_state %d?\n", cuda_state);
721     }
722     spin_unlock_irqrestore(&cuda_lock, flags);
723     if (complete && req) {
724     	void (*done)(struct adb_request *) = req->done;
725     	mb();
726     	req->complete = 1;
727     	/* Here, we assume that if the request has a done member, the
728     	 * struct request will survive to setting req->complete to 1
729     	 */
730     	if (done)
731 		(*done)(req);
732     }
733     if (ibuf_len)
734 	cuda_input(ibuf, ibuf_len);
735     return IRQ_HANDLED;
736 }
737 
738 static void
739 cuda_input(unsigned char *buf, int nb)
740 {
741     switch (buf[0]) {
742     case ADB_PACKET:
743 #ifdef CONFIG_XMON
744 	if (nb == 5 && buf[2] == 0x2c) {
745 	    extern int xmon_wants_key, xmon_adb_keycode;
746 	    if (xmon_wants_key) {
747 		xmon_adb_keycode = buf[3];
748 		return;
749 	    }
750 	}
751 #endif /* CONFIG_XMON */
752 #ifdef CONFIG_ADB
753 	adb_input(buf+2, nb-2, buf[1] & 0x40);
754 #endif /* CONFIG_ADB */
755 	break;
756 
757     case TIMER_PACKET:
758 	/* Egret sends these periodically. Might be useful as a 'heartbeat'
759 	 * to trigger a recovery for the VIA shift register errata.
760 	 */
761 	break;
762 
763     default:
764 	print_hex_dump(KERN_INFO, "cuda_input: ", DUMP_PREFIX_NONE, 32, 1,
765 	               buf, nb, false);
766     }
767 }
768