Pull bugzilla-9429 into release branch
[pv_ops_mirror.git] / drivers / macintosh / via-maciisi.c
blob2dc788042707fb6dd6abc78abafc84d678c977cd
1 /*
2 * Device driver for the IIsi-style ADB on some Mac LC and II-class machines
4 * Based on via-cuda.c and via-macii.c, as well as the original
5 * adb-bus.c, which in turn is somewhat influenced by (but uses no
6 * code from) the NetBSD HWDIRECT ADB code. Original IIsi driver work
7 * was done by Robert Thompson and integrated into the old style
8 * driver by Michael Schmitz.
10 * Original sources (c) Alan Cox, Paul Mackerras, and others.
12 * Rewritten for Unified ADB by David Huggins-Daines <dhd@debian.org>
14 * 7/13/2000- extensive changes by Andrew McPherson <andrew@macduff.dhs.org>
15 * Works about 30% of the time now.
18 #include <linux/types.h>
19 #include <linux/errno.h>
20 #include <linux/kernel.h>
21 #include <linux/adb.h>
22 #include <linux/cuda.h>
23 #include <linux/delay.h>
24 #include <linux/interrupt.h>
25 #include <asm/macintosh.h>
26 #include <asm/macints.h>
27 #include <asm/machw.h>
28 #include <asm/mac_via.h>
30 static volatile unsigned char *via;
32 /* VIA registers - spaced 0x200 bytes apart - only the ones we actually use */
33 #define RS 0x200 /* skip between registers */
34 #define B 0 /* B-side data */
35 #define A RS /* A-side data */
36 #define DIRB (2*RS) /* B-side direction (1=output) */
37 #define DIRA (3*RS) /* A-side direction (1=output) */
38 #define SR (10*RS) /* Shift register */
39 #define ACR (11*RS) /* Auxiliary control register */
40 #define IFR (13*RS) /* Interrupt flag register */
41 #define IER (14*RS) /* Interrupt enable register */
43 /* Bits in B data register: all active low */
44 #define TREQ 0x08 /* Transfer request (input) */
45 #define TACK 0x10 /* Transfer acknowledge (output) */
46 #define TIP 0x20 /* Transfer in progress (output) */
47 #define ST_MASK 0x30 /* mask for selecting ADB state bits */
49 /* Bits in ACR */
50 #define SR_CTRL 0x1c /* Shift register control bits */
51 #define SR_EXT 0x0c /* Shift on external clock */
52 #define SR_OUT 0x10 /* Shift out if 1 */
54 /* Bits in IFR and IER */
55 #define IER_SET 0x80 /* set bits in IER */
56 #define IER_CLR 0 /* clear bits in IER */
57 #define SR_INT 0x04 /* Shift register full/empty */
58 #define SR_DATA 0x08 /* Shift register data */
59 #define SR_CLOCK 0x10 /* Shift register clock */
61 #define ADB_DELAY 150
63 #undef DEBUG_MACIISI_ADB
65 static struct adb_request* current_req;
66 static struct adb_request* last_req;
67 static unsigned char maciisi_rbuf[16];
68 static unsigned char *reply_ptr;
69 static int data_index;
70 static int reading_reply;
71 static int reply_len;
72 static int tmp;
73 static int need_sync;
75 static enum maciisi_state {
76 idle,
77 sending,
78 reading,
79 } maciisi_state;
81 static int maciisi_probe(void);
82 static int maciisi_init(void);
83 static int maciisi_send_request(struct adb_request* req, int sync);
84 static void maciisi_sync(struct adb_request *req);
85 static int maciisi_write(struct adb_request* req);
86 static irqreturn_t maciisi_interrupt(int irq, void* arg);
87 static void maciisi_input(unsigned char *buf, int nb);
88 static int maciisi_init_via(void);
89 static void maciisi_poll(void);
90 static int maciisi_start(void);
92 struct adb_driver via_maciisi_driver = {
93 "Mac IIsi",
94 maciisi_probe,
95 maciisi_init,
96 maciisi_send_request,
97 NULL, /* maciisi_adb_autopoll, */
98 maciisi_poll,
99 NULL /* maciisi_reset_adb_bus */
102 static int
103 maciisi_probe(void)
105 if (macintosh_config->adb_type != MAC_ADB_IISI)
106 return -ENODEV;
108 via = via1;
109 return 0;
112 static int
113 maciisi_init(void)
115 int err;
117 if (via == NULL)
118 return -ENODEV;
120 if ((err = maciisi_init_via())) {
121 printk(KERN_ERR "maciisi_init: maciisi_init_via() failed, code %d\n", err);
122 via = NULL;
123 return err;
126 if (request_irq(IRQ_MAC_ADB, maciisi_interrupt, IRQ_FLG_LOCK | IRQ_FLG_FAST,
127 "ADB", maciisi_interrupt)) {
128 printk(KERN_ERR "maciisi_init: can't get irq %d\n", IRQ_MAC_ADB);
129 return -EAGAIN;
132 printk("adb: Mac IIsi driver v0.2 for Unified ADB.\n");
133 return 0;
136 /* Flush data from the ADB controller */
137 static void
138 maciisi_stfu(void)
140 int status = via[B] & (TIP|TREQ);
142 if (status & TREQ) {
143 #ifdef DEBUG_MACIISI_ADB
144 printk (KERN_DEBUG "maciisi_stfu called with TREQ high!\n");
145 #endif
146 return;
149 udelay(ADB_DELAY);
150 via[ACR] &= ~SR_OUT;
151 via[IER] = IER_CLR | SR_INT;
153 udelay(ADB_DELAY);
155 status = via[B] & (TIP|TREQ);
157 if (!(status & TREQ))
159 via[B] |= TIP;
161 while(1)
163 int poll_timeout = ADB_DELAY * 5;
164 /* Poll for SR interrupt */
165 while (!(via[IFR] & SR_INT) && poll_timeout-- > 0)
166 status = via[B] & (TIP|TREQ);
168 tmp = via[SR]; /* Clear shift register */
169 #ifdef DEBUG_MACIISI_ADB
170 printk(KERN_DEBUG "maciisi_stfu: status %x timeout %d data %x\n",
171 status, poll_timeout, tmp);
172 #endif
173 if(via[B] & TREQ)
174 break;
176 /* ACK on-off */
177 via[B] |= TACK;
178 udelay(ADB_DELAY);
179 via[B] &= ~TACK;
182 /* end frame */
183 via[B] &= ~TIP;
184 udelay(ADB_DELAY);
187 via[IER] = IER_SET | SR_INT;
190 /* All specifically VIA-related initialization goes here */
191 static int
192 maciisi_init_via(void)
194 int i;
196 /* Set the lines up. We want TREQ as input TACK|TIP as output */
197 via[DIRB] = (via[DIRB] | TACK | TIP) & ~TREQ;
198 /* Shift register on input */
199 via[ACR] = (via[ACR] & ~SR_CTRL) | SR_EXT;
200 #ifdef DEBUG_MACIISI_ADB
201 printk(KERN_DEBUG "maciisi_init_via: initial status %x\n", via[B] & (TIP|TREQ));
202 #endif
203 /* Wipe any pending data and int */
204 tmp = via[SR];
205 /* Enable keyboard interrupts */
206 via[IER] = IER_SET | SR_INT;
207 /* Set initial state: idle */
208 via[B] &= ~(TACK|TIP);
209 /* Clear interrupt bit */
210 via[IFR] = SR_INT;
212 for(i = 0; i < 60; i++) {
213 udelay(ADB_DELAY);
214 maciisi_stfu();
215 udelay(ADB_DELAY);
216 if(via[B] & TREQ)
217 break;
219 if (i == 60)
220 printk(KERN_ERR "maciisi_init_via: bus jam?\n");
222 maciisi_state = idle;
223 need_sync = 0;
225 return 0;
228 /* Send a request, possibly waiting for a reply */
229 static int
230 maciisi_send_request(struct adb_request* req, int sync)
232 int i;
234 #ifdef DEBUG_MACIISI_ADB
235 static int dump_packet = 0;
236 #endif
238 if (via == NULL) {
239 req->complete = 1;
240 return -ENXIO;
243 #ifdef DEBUG_MACIISI_ADB
244 if (dump_packet) {
245 printk(KERN_DEBUG "maciisi_send_request:");
246 for (i = 0; i < req->nbytes; i++) {
247 printk(" %.2x", req->data[i]);
249 printk(" sync %d\n", sync);
251 #endif
253 req->reply_expected = 1;
255 i = maciisi_write(req);
256 if (i)
258 /* Normally, if a packet requires syncing, that happens at the end of
259 * maciisi_send_request. But if the transfer fails, it will be restarted
260 * by maciisi_interrupt(). We use need_sync to tell maciisi_interrupt
261 * when to sync a packet that it sends out.
263 * Suggestions on a better way to do this are welcome.
265 if(i == -EBUSY && sync)
266 need_sync = 1;
267 else
268 need_sync = 0;
269 return i;
271 if(sync)
272 maciisi_sync(req);
274 return 0;
277 /* Poll the ADB chip until the request completes */
278 static void maciisi_sync(struct adb_request *req)
280 int count = 0;
282 #ifdef DEBUG_MACIISI_ADB
283 printk(KERN_DEBUG "maciisi_sync called\n");
284 #endif
286 /* If for some reason the ADB chip shuts up on us, we want to avoid an endless loop. */
287 while (!req->complete && count++ < 50) {
288 maciisi_poll();
290 /* This could be BAD... when the ADB controller doesn't respond
291 * for this long, it's probably not coming back :-( */
292 if(count >= 50) /* Hopefully shouldn't happen */
293 printk(KERN_ERR "maciisi_send_request: poll timed out!\n");
297 maciisi_request(struct adb_request *req, void (*done)(struct adb_request *),
298 int nbytes, ...)
300 va_list list;
301 int i;
303 req->nbytes = nbytes;
304 req->done = done;
305 req->reply_expected = 0;
306 va_start(list, nbytes);
307 for (i = 0; i < nbytes; i++)
308 req->data[i++] = va_arg(list, int);
309 va_end(list);
311 return maciisi_send_request(req, 1);
314 /* Enqueue a request, and run the queue if possible */
315 static int
316 maciisi_write(struct adb_request* req)
318 unsigned long flags;
319 int i;
321 /* We will accept CUDA packets - the VIA sends them to us, so
322 it figures that we should be able to send them to it */
323 if (req->nbytes < 2 || req->data[0] > CUDA_PACKET) {
324 printk(KERN_ERR "maciisi_write: packet too small or not an ADB or CUDA packet\n");
325 req->complete = 1;
326 return -EINVAL;
328 req->next = NULL;
329 req->sent = 0;
330 req->complete = 0;
331 req->reply_len = 0;
333 local_irq_save(flags);
335 if (current_req) {
336 last_req->next = req;
337 last_req = req;
338 } else {
339 current_req = req;
340 last_req = req;
342 if (maciisi_state == idle)
344 i = maciisi_start();
345 if(i != 0)
347 local_irq_restore(flags);
348 return i;
351 else
353 #ifdef DEBUG_MACIISI_ADB
354 printk(KERN_DEBUG "maciisi_write: would start, but state is %d\n", maciisi_state);
355 #endif
356 local_irq_restore(flags);
357 return -EBUSY;
360 local_irq_restore(flags);
362 return 0;
365 static int
366 maciisi_start(void)
368 struct adb_request* req;
369 int status;
371 #ifdef DEBUG_MACIISI_ADB
372 status = via[B] & (TIP | TREQ);
374 printk(KERN_DEBUG "maciisi_start called, state=%d, status=%x, ifr=%x\n", maciisi_state, status, via[IFR]);
375 #endif
377 if (maciisi_state != idle) {
378 /* shouldn't happen */
379 printk(KERN_ERR "maciisi_start: maciisi_start called when driver busy!\n");
380 return -EBUSY;
383 req = current_req;
384 if (req == NULL)
385 return -EINVAL;
387 status = via[B] & (TIP|TREQ);
388 if (!(status & TREQ)) {
389 #ifdef DEBUG_MACIISI_ADB
390 printk(KERN_DEBUG "maciisi_start: bus busy - aborting\n");
391 #endif
392 return -EBUSY;
395 /* Okay, send */
396 #ifdef DEBUG_MACIISI_ADB
397 printk(KERN_DEBUG "maciisi_start: sending\n");
398 #endif
399 /* Set state to active */
400 via[B] |= TIP;
401 /* ACK off */
402 via[B] &= ~TACK;
403 /* Delay */
404 udelay(ADB_DELAY);
405 /* Shift out and send */
406 via[ACR] |= SR_OUT;
407 via[SR] = req->data[0];
408 data_index = 1;
409 /* ACK on */
410 via[B] |= TACK;
411 maciisi_state = sending;
413 return 0;
416 void
417 maciisi_poll(void)
419 unsigned long flags;
421 local_irq_save(flags);
422 if (via[IFR] & SR_INT) {
423 maciisi_interrupt(0, NULL);
425 else /* avoid calling this function too quickly in a loop */
426 udelay(ADB_DELAY);
428 local_irq_restore(flags);
431 /* Shift register interrupt - this is *supposed* to mean that the
432 register is either full or empty. In practice, I have no idea what
433 it means :( */
434 static irqreturn_t
435 maciisi_interrupt(int irq, void* arg)
437 int status;
438 struct adb_request *req;
439 #ifdef DEBUG_MACIISI_ADB
440 static int dump_reply = 0;
441 #endif
442 int i;
443 unsigned long flags;
445 local_irq_save(flags);
447 status = via[B] & (TIP|TREQ);
448 #ifdef DEBUG_MACIISI_ADB
449 printk(KERN_DEBUG "state %d status %x ifr %x\n", maciisi_state, status, via[IFR]);
450 #endif
452 if (!(via[IFR] & SR_INT)) {
453 /* Shouldn't happen, we hope */
454 printk(KERN_ERR "maciisi_interrupt: called without interrupt flag set\n");
455 local_irq_restore(flags);
456 return IRQ_NONE;
459 /* Clear the interrupt */
460 /* via[IFR] = SR_INT; */
462 switch_start:
463 switch (maciisi_state) {
464 case idle:
465 if (status & TIP)
466 printk(KERN_ERR "maciisi_interrupt: state is idle but TIP asserted!\n");
468 if(!reading_reply)
469 udelay(ADB_DELAY);
470 /* Shift in */
471 via[ACR] &= ~SR_OUT;
472 /* Signal start of frame */
473 via[B] |= TIP;
474 /* Clear the interrupt (throw this value on the floor, it's useless) */
475 tmp = via[SR];
476 /* ACK adb chip, high-low */
477 via[B] |= TACK;
478 udelay(ADB_DELAY);
479 via[B] &= ~TACK;
480 reply_len = 0;
481 maciisi_state = reading;
482 if (reading_reply) {
483 reply_ptr = current_req->reply;
484 } else {
485 reply_ptr = maciisi_rbuf;
487 break;
489 case sending:
490 /* via[SR]; */
491 /* Set ACK off */
492 via[B] &= ~TACK;
493 req = current_req;
495 if (!(status & TREQ)) {
496 /* collision */
497 printk(KERN_ERR "maciisi_interrupt: send collision\n");
498 /* Set idle and input */
499 via[ACR] &= ~SR_OUT;
500 tmp = via[SR];
501 via[B] &= ~TIP;
502 /* Must re-send */
503 reading_reply = 0;
504 reply_len = 0;
505 maciisi_state = idle;
506 udelay(ADB_DELAY);
507 /* process this now, because the IFR has been cleared */
508 goto switch_start;
511 udelay(ADB_DELAY);
513 if (data_index >= req->nbytes) {
514 /* Sent the whole packet, put the bus back in idle state */
515 /* Shift in, we are about to read a reply (hopefully) */
516 via[ACR] &= ~SR_OUT;
517 tmp = via[SR];
518 /* End of frame */
519 via[B] &= ~TIP;
520 req->sent = 1;
521 maciisi_state = idle;
522 if (req->reply_expected) {
523 /* Note: only set this once we've
524 successfully sent the packet */
525 reading_reply = 1;
526 } else {
527 current_req = req->next;
528 if (req->done)
529 (*req->done)(req);
530 /* Do any queued requests now */
531 i = maciisi_start();
532 if(i == 0 && need_sync) {
533 /* Packet needs to be synced */
534 maciisi_sync(current_req);
536 if(i != -EBUSY)
537 need_sync = 0;
539 } else {
540 /* Sending more stuff */
541 /* Shift out */
542 via[ACR] |= SR_OUT;
543 /* Write */
544 via[SR] = req->data[data_index++];
545 /* Signal 'byte ready' */
546 via[B] |= TACK;
548 break;
550 case reading:
551 /* Shift in */
552 /* via[ACR] &= ~SR_OUT; */ /* Not in 2.2 */
553 if (reply_len++ > 16) {
554 printk(KERN_ERR "maciisi_interrupt: reply too long, aborting read\n");
555 via[B] |= TACK;
556 udelay(ADB_DELAY);
557 via[B] &= ~(TACK|TIP);
558 maciisi_state = idle;
559 i = maciisi_start();
560 if(i == 0 && need_sync) {
561 /* Packet needs to be synced */
562 maciisi_sync(current_req);
564 if(i != -EBUSY)
565 need_sync = 0;
566 break;
568 /* Read data */
569 *reply_ptr++ = via[SR];
570 status = via[B] & (TIP|TREQ);
571 /* ACK on/off */
572 via[B] |= TACK;
573 udelay(ADB_DELAY);
574 via[B] &= ~TACK;
575 if (!(status & TREQ))
576 break; /* more stuff to deal with */
578 /* end of frame */
579 via[B] &= ~TIP;
580 tmp = via[SR]; /* That's what happens in 2.2 */
581 udelay(ADB_DELAY); /* Give controller time to recover */
583 /* end of packet, deal with it */
584 if (reading_reply) {
585 req = current_req;
586 req->reply_len = reply_ptr - req->reply;
587 if (req->data[0] == ADB_PACKET) {
588 /* Have to adjust the reply from ADB commands */
589 if (req->reply_len <= 2 || (req->reply[1] & 2) != 0) {
590 /* the 0x2 bit indicates no response */
591 req->reply_len = 0;
592 } else {
593 /* leave just the command and result bytes in the reply */
594 req->reply_len -= 2;
595 memmove(req->reply, req->reply + 2, req->reply_len);
598 #ifdef DEBUG_MACIISI_ADB
599 if (dump_reply) {
600 int i;
601 printk(KERN_DEBUG "maciisi_interrupt: reply is ");
602 for (i = 0; i < req->reply_len; ++i)
603 printk(" %.2x", req->reply[i]);
604 printk("\n");
606 #endif
607 req->complete = 1;
608 current_req = req->next;
609 if (req->done)
610 (*req->done)(req);
611 /* Obviously, we got it */
612 reading_reply = 0;
613 } else {
614 maciisi_input(maciisi_rbuf, reply_ptr - maciisi_rbuf);
616 maciisi_state = idle;
617 status = via[B] & (TIP|TREQ);
618 if (!(status & TREQ)) {
619 /* Timeout?! More likely, another packet coming in already */
620 #ifdef DEBUG_MACIISI_ADB
621 printk(KERN_DEBUG "extra data after packet: status %x ifr %x\n",
622 status, via[IFR]);
623 #endif
624 #if 0
625 udelay(ADB_DELAY);
626 via[B] |= TIP;
628 maciisi_state = reading;
629 reading_reply = 0;
630 reply_ptr = maciisi_rbuf;
631 #else
632 /* Process the packet now */
633 reading_reply = 0;
634 goto switch_start;
635 #endif
636 /* We used to do this... but the controller might actually have data for us */
637 /* maciisi_stfu(); */
639 else {
640 /* Do any queued requests now if possible */
641 i = maciisi_start();
642 if(i == 0 && need_sync) {
643 /* Packet needs to be synced */
644 maciisi_sync(current_req);
646 if(i != -EBUSY)
647 need_sync = 0;
649 break;
651 default:
652 printk("maciisi_interrupt: unknown maciisi_state %d?\n", maciisi_state);
654 local_irq_restore(flags);
655 return IRQ_HANDLED;
658 static void
659 maciisi_input(unsigned char *buf, int nb)
661 #ifdef DEBUG_MACIISI_ADB
662 int i;
663 #endif
665 switch (buf[0]) {
666 case ADB_PACKET:
667 adb_input(buf+2, nb-2, buf[1] & 0x40);
668 break;
669 default:
670 #ifdef DEBUG_MACIISI_ADB
671 printk(KERN_DEBUG "data from IIsi ADB (%d bytes):", nb);
672 for (i = 0; i < nb; ++i)
673 printk(" %.2x", buf[i]);
674 printk("\n");
675 #endif
676 break;