blob: 2d9d79150403b17996f034a8165a45ea28a687b5 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * Device driver for the via-cuda on Apple Powermacs.
3 *
4 * The VIA (versatile interface adapter) interfaces to the CUDA,
5 * a 6805 microprocessor core which controls the ADB (Apple Desktop
6 * Bus) which connects to the keyboard and mouse. The CUDA also
7 * controls system power and the RTC (real time clock) chip.
8 *
9 * Copyright (C) 1996 Paul Mackerras.
10 */
11#include <stdarg.h>
12#include <linux/config.h>
13#include <linux/types.h>
14#include <linux/errno.h>
15#include <linux/kernel.h>
16#include <linux/delay.h>
17#include <linux/sched.h>
18#include <linux/adb.h>
19#include <linux/cuda.h>
20#include <linux/spinlock.h>
21#include <linux/interrupt.h>
22#ifdef CONFIG_PPC
23#include <asm/prom.h>
24#include <asm/machdep.h>
25#else
26#include <asm/macintosh.h>
27#include <asm/macints.h>
28#include <asm/machw.h>
29#include <asm/mac_via.h>
30#endif
31#include <asm/io.h>
32#include <asm/system.h>
33#include <linux/init.h>
34
35static volatile unsigned char __iomem *via;
36static DEFINE_SPINLOCK(cuda_lock);
37
38#ifdef CONFIG_MAC
39#define CUDA_IRQ IRQ_MAC_ADB
Linus Torvalds1da177e2005-04-16 15:20:36 -070040#define eieio()
41#else
42#define CUDA_IRQ vias->intrs[0].line
43#endif
44
45/* VIA registers - spaced 0x200 bytes apart */
46#define RS 0x200 /* skip between registers */
47#define B 0 /* B-side data */
48#define A RS /* A-side data */
49#define DIRB (2*RS) /* B-side direction (1=output) */
50#define DIRA (3*RS) /* A-side direction (1=output) */
51#define T1CL (4*RS) /* Timer 1 ctr/latch (low 8 bits) */
52#define T1CH (5*RS) /* Timer 1 counter (high 8 bits) */
53#define T1LL (6*RS) /* Timer 1 latch (low 8 bits) */
54#define T1LH (7*RS) /* Timer 1 latch (high 8 bits) */
55#define T2CL (8*RS) /* Timer 2 ctr/latch (low 8 bits) */
56#define T2CH (9*RS) /* Timer 2 counter (high 8 bits) */
57#define SR (10*RS) /* Shift register */
58#define ACR (11*RS) /* Auxiliary control register */
59#define PCR (12*RS) /* Peripheral control register */
60#define IFR (13*RS) /* Interrupt flag register */
61#define IER (14*RS) /* Interrupt enable register */
62#define ANH (15*RS) /* A-side data, no handshake */
63
64/* Bits in B data register: all active low */
65#define TREQ 0x08 /* Transfer request (input) */
66#define TACK 0x10 /* Transfer acknowledge (output) */
67#define TIP 0x20 /* Transfer in progress (output) */
68
69/* Bits in ACR */
70#define SR_CTRL 0x1c /* Shift register control bits */
71#define SR_EXT 0x0c /* Shift on external clock */
72#define SR_OUT 0x10 /* Shift out if 1 */
73
74/* Bits in IFR and IER */
75#define IER_SET 0x80 /* set bits in IER */
76#define IER_CLR 0 /* clear bits in IER */
77#define SR_INT 0x04 /* Shift register full/empty */
78
79static enum cuda_state {
80 idle,
81 sent_first_byte,
82 sending,
83 reading,
84 read_done,
85 awaiting_reply
86} cuda_state;
87
88static struct adb_request *current_req;
89static struct adb_request *last_req;
90static unsigned char cuda_rbuf[16];
91static unsigned char *reply_ptr;
92static int reading_reply;
93static int data_index;
94#ifdef CONFIG_PPC
95static struct device_node *vias;
96#endif
97static int cuda_fully_inited = 0;
98
99#ifdef CONFIG_ADB
100static int cuda_probe(void);
101static int cuda_init(void);
102static int cuda_send_request(struct adb_request *req, int sync);
103static int cuda_adb_autopoll(int devs);
104static int cuda_reset_adb_bus(void);
105#endif /* CONFIG_ADB */
106
107static int cuda_init_via(void);
108static void cuda_start(void);
109static irqreturn_t cuda_interrupt(int irq, void *arg, struct pt_regs *regs);
110static void cuda_input(unsigned char *buf, int nb, struct pt_regs *regs);
111void cuda_poll(void);
112static int cuda_write(struct adb_request *req);
113
114int cuda_request(struct adb_request *req,
115 void (*done)(struct adb_request *), int nbytes, ...);
116
117#ifdef CONFIG_ADB
118struct adb_driver via_cuda_driver = {
119 "CUDA",
120 cuda_probe,
121 cuda_init,
122 cuda_send_request,
123 cuda_adb_autopoll,
124 cuda_poll,
125 cuda_reset_adb_bus
126};
127#endif /* CONFIG_ADB */
128
129#ifdef CONFIG_PPC
Benjamin Herrenschmidt51d30822005-11-23 17:57:25 +1100130int __init find_via_cuda(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700131{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700132 struct adb_request req;
Benjamin Herrenschmidt51d30822005-11-23 17:57:25 +1100133 phys_addr_t taddr;
134 u32 *reg;
135 int err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700136
137 if (vias != 0)
138 return 1;
Benjamin Herrenschmidt51d30822005-11-23 17:57:25 +1100139 vias = of_find_node_by_name(NULL, "via-cuda");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700140 if (vias == 0)
141 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700142
Benjamin Herrenschmidt51d30822005-11-23 17:57:25 +1100143 reg = (u32 *)get_property(vias, "reg", NULL);
144 if (reg == NULL) {
145 printk(KERN_ERR "via-cuda: No \"reg\" property !\n");
146 goto fail;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700147 }
Benjamin Herrenschmidt51d30822005-11-23 17:57:25 +1100148 taddr = of_translate_address(vias, reg);
149 if (taddr == 0) {
150 printk(KERN_ERR "via-cuda: Can't translate address !\n");
151 goto fail;
152 }
153 via = ioremap(taddr, 0x2000);
154 if (via == NULL) {
155 printk(KERN_ERR "via-cuda: Can't map address !\n");
156 goto fail;
157 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700158
159 cuda_state = idle;
160 sys_ctrler = SYS_CTRLER_CUDA;
161
162 err = cuda_init_via();
163 if (err) {
164 printk(KERN_ERR "cuda_init_via() failed\n");
165 via = NULL;
166 return 0;
167 }
168
169 /* Clear and enable interrupts, but only on PPC. On 68K it's done */
170 /* for us by the main VIA driver in arch/m68k/mac/via.c */
171
172#ifndef CONFIG_MAC
173 out_8(&via[IFR], 0x7f); /* clear interrupts by writing 1s */
174 out_8(&via[IER], IER_SET|SR_INT); /* enable interrupt from SR */
175#endif
176
177 /* enable autopoll */
178 cuda_request(&req, NULL, 3, CUDA_PACKET, CUDA_AUTOPOLL, 1);
179 while (!req.complete)
180 cuda_poll();
181
182 return 1;
Benjamin Herrenschmidt51d30822005-11-23 17:57:25 +1100183
184 fail:
185 of_node_put(vias);
186 vias = NULL;
187 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700188}
189#endif /* CONFIG_PPC */
190
191static int __init via_cuda_start(void)
192{
193 if (via == NULL)
194 return -ENODEV;
195
Linus Torvalds1da177e2005-04-16 15:20:36 -0700196 if (request_irq(CUDA_IRQ, cuda_interrupt, 0, "ADB", cuda_interrupt)) {
197 printk(KERN_ERR "cuda_init: can't get irq %d\n", CUDA_IRQ);
198 return -EAGAIN;
199 }
200
201 printk("Macintosh CUDA driver v0.5 for Unified ADB.\n");
202
203 cuda_fully_inited = 1;
204 return 0;
205}
206
207device_initcall(via_cuda_start);
208
209#ifdef CONFIG_ADB
210static int
211cuda_probe(void)
212{
213#ifdef CONFIG_PPC
214 if (sys_ctrler != SYS_CTRLER_CUDA)
215 return -ENODEV;
216#else
217 if (macintosh_config->adb_type != MAC_ADB_CUDA)
218 return -ENODEV;
219 via = via1;
220#endif
221 return 0;
222}
223
224static int __init
225cuda_init(void)
226{
227#ifdef CONFIG_PPC
228 if (via == NULL)
229 return -ENODEV;
230 return 0;
231#else
232 int err = cuda_init_via();
233 if (err) {
234 printk(KERN_ERR "cuda_init_via() failed\n");
235 return -ENODEV;
236 }
237
238 return via_cuda_start();
239#endif
240}
241#endif /* CONFIG_ADB */
242
243#define WAIT_FOR(cond, what) \
244 do { \
245 int x; \
246 for (x = 1000; !(cond); --x) { \
247 if (x == 0) { \
248 printk("Timeout waiting for " what "\n"); \
249 return -ENXIO; \
250 } \
251 udelay(100); \
252 } \
253 } while (0)
254
255static int
256cuda_init_via(void)
257{
258 out_8(&via[DIRB], (in_8(&via[DIRB]) | TACK | TIP) & ~TREQ); /* TACK & TIP out */
259 out_8(&via[B], in_8(&via[B]) | TACK | TIP); /* negate them */
260 out_8(&via[ACR] ,(in_8(&via[ACR]) & ~SR_CTRL) | SR_EXT); /* SR data in */
261 (void)in_8(&via[SR]); /* clear any left-over data */
262#ifndef CONFIG_MAC
263 out_8(&via[IER], 0x7f); /* disable interrupts from VIA */
264 (void)in_8(&via[IER]);
265#endif
266
267 /* delay 4ms and then clear any pending interrupt */
268 mdelay(4);
269 (void)in_8(&via[SR]);
270 out_8(&via[IFR], in_8(&via[IFR]) & 0x7f);
271
272 /* sync with the CUDA - assert TACK without TIP */
273 out_8(&via[B], in_8(&via[B]) & ~TACK);
274
275 /* wait for the CUDA to assert TREQ in response */
276 WAIT_FOR((in_8(&via[B]) & TREQ) == 0, "CUDA response to sync");
277
278 /* wait for the interrupt and then clear it */
279 WAIT_FOR(in_8(&via[IFR]) & SR_INT, "CUDA response to sync (2)");
280 (void)in_8(&via[SR]);
281 out_8(&via[IFR], in_8(&via[IFR]) & 0x7f);
282
283 /* finish the sync by negating TACK */
284 out_8(&via[B], in_8(&via[B]) | TACK);
285
286 /* wait for the CUDA to negate TREQ and the corresponding interrupt */
287 WAIT_FOR(in_8(&via[B]) & TREQ, "CUDA response to sync (3)");
288 WAIT_FOR(in_8(&via[IFR]) & SR_INT, "CUDA response to sync (4)");
289 (void)in_8(&via[SR]);
290 out_8(&via[IFR], in_8(&via[IFR]) & 0x7f);
291 out_8(&via[B], in_8(&via[B]) | TIP); /* should be unnecessary */
292
293 return 0;
294}
295
296#ifdef CONFIG_ADB
297/* Send an ADB command */
298static int
299cuda_send_request(struct adb_request *req, int sync)
300{
301 int i;
302
303 if ((via == NULL) || !cuda_fully_inited) {
304 req->complete = 1;
305 return -ENXIO;
306 }
307
308 req->reply_expected = 1;
309
310 i = cuda_write(req);
311 if (i)
312 return i;
313
314 if (sync) {
315 while (!req->complete)
316 cuda_poll();
317 }
318 return 0;
319}
320
321
322/* Enable/disable autopolling */
323static int
324cuda_adb_autopoll(int devs)
325{
326 struct adb_request req;
327
328 if ((via == NULL) || !cuda_fully_inited)
329 return -ENXIO;
330
331 cuda_request(&req, NULL, 3, CUDA_PACKET, CUDA_AUTOPOLL, (devs? 1: 0));
332 while (!req.complete)
333 cuda_poll();
334 return 0;
335}
336
337/* Reset adb bus - how do we do this?? */
338static int
339cuda_reset_adb_bus(void)
340{
341 struct adb_request req;
342
343 if ((via == NULL) || !cuda_fully_inited)
344 return -ENXIO;
345
346 cuda_request(&req, NULL, 2, ADB_PACKET, 0); /* maybe? */
347 while (!req.complete)
348 cuda_poll();
349 return 0;
350}
351#endif /* CONFIG_ADB */
352/* Construct and send a cuda request */
353int
354cuda_request(struct adb_request *req, void (*done)(struct adb_request *),
355 int nbytes, ...)
356{
357 va_list list;
358 int i;
359
360 if (via == NULL) {
361 req->complete = 1;
362 return -ENXIO;
363 }
364
365 req->nbytes = nbytes;
366 req->done = done;
367 va_start(list, nbytes);
368 for (i = 0; i < nbytes; ++i)
369 req->data[i] = va_arg(list, int);
370 va_end(list);
371 req->reply_expected = 1;
372 return cuda_write(req);
373}
374
375static int
376cuda_write(struct adb_request *req)
377{
378 unsigned long flags;
379
380 if (req->nbytes < 2 || req->data[0] > CUDA_PACKET) {
381 req->complete = 1;
382 return -EINVAL;
383 }
384 req->next = NULL;
385 req->sent = 0;
386 req->complete = 0;
387 req->reply_len = 0;
388
389 spin_lock_irqsave(&cuda_lock, flags);
390 if (current_req != 0) {
391 last_req->next = req;
392 last_req = req;
393 } else {
394 current_req = req;
395 last_req = req;
396 if (cuda_state == idle)
397 cuda_start();
398 }
399 spin_unlock_irqrestore(&cuda_lock, flags);
400
401 return 0;
402}
403
404static void
405cuda_start(void)
406{
407 struct adb_request *req;
408
409 /* assert cuda_state == idle */
410 /* get the packet to send */
411 req = current_req;
412 if (req == 0)
413 return;
414 if ((in_8(&via[B]) & TREQ) == 0)
415 return; /* a byte is coming in from the CUDA */
416
417 /* set the shift register to shift out and send a byte */
418 out_8(&via[ACR], in_8(&via[ACR]) | SR_OUT);
419 out_8(&via[SR], req->data[0]);
420 out_8(&via[B], in_8(&via[B]) & ~TIP);
421 cuda_state = sent_first_byte;
422}
423
424void
425cuda_poll(void)
426{
427 unsigned long flags;
428
429 /* cuda_interrupt only takes a normal lock, we disable
430 * interrupts here to avoid re-entering and thus deadlocking.
431 * An option would be to disable only the IRQ source with
432 * disable_irq(), would that work on m68k ? --BenH
433 */
434 local_irq_save(flags);
435 cuda_interrupt(0, NULL, NULL);
436 local_irq_restore(flags);
437}
438
439static irqreturn_t
440cuda_interrupt(int irq, void *arg, struct pt_regs *regs)
441{
442 int status;
443 struct adb_request *req = NULL;
444 unsigned char ibuf[16];
445 int ibuf_len = 0;
446 int complete = 0;
447 unsigned char virq;
448
449 spin_lock(&cuda_lock);
450
451 virq = in_8(&via[IFR]) & 0x7f;
452 out_8(&via[IFR], virq);
453 if ((virq & SR_INT) == 0) {
454 spin_unlock(&cuda_lock);
455 return IRQ_NONE;
456 }
457
458 status = (~in_8(&via[B]) & (TIP|TREQ)) | (in_8(&via[ACR]) & SR_OUT);
459 /* printk("cuda_interrupt: state=%d status=%x\n", cuda_state, status); */
460 switch (cuda_state) {
461 case idle:
462 /* CUDA has sent us the first byte of data - unsolicited */
463 if (status != TREQ)
464 printk("cuda: state=idle, status=%x\n", status);
465 (void)in_8(&via[SR]);
466 out_8(&via[B], in_8(&via[B]) & ~TIP);
467 cuda_state = reading;
468 reply_ptr = cuda_rbuf;
469 reading_reply = 0;
470 break;
471
472 case awaiting_reply:
473 /* CUDA has sent us the first byte of data of a reply */
474 if (status != TREQ)
475 printk("cuda: state=awaiting_reply, status=%x\n", status);
476 (void)in_8(&via[SR]);
477 out_8(&via[B], in_8(&via[B]) & ~TIP);
478 cuda_state = reading;
479 reply_ptr = current_req->reply;
480 reading_reply = 1;
481 break;
482
483 case sent_first_byte:
484 if (status == TREQ + TIP + SR_OUT) {
485 /* collision */
486 out_8(&via[ACR], in_8(&via[ACR]) & ~SR_OUT);
487 (void)in_8(&via[SR]);
488 out_8(&via[B], in_8(&via[B]) | TIP | TACK);
489 cuda_state = idle;
490 } else {
491 /* assert status == TIP + SR_OUT */
492 if (status != TIP + SR_OUT)
493 printk("cuda: state=sent_first_byte status=%x\n", status);
494 out_8(&via[SR], current_req->data[1]);
495 out_8(&via[B], in_8(&via[B]) ^ TACK);
496 data_index = 2;
497 cuda_state = sending;
498 }
499 break;
500
501 case sending:
502 req = current_req;
503 if (data_index >= req->nbytes) {
504 out_8(&via[ACR], in_8(&via[ACR]) & ~SR_OUT);
505 (void)in_8(&via[SR]);
506 out_8(&via[B], in_8(&via[B]) | TACK | TIP);
507 req->sent = 1;
508 if (req->reply_expected) {
509 cuda_state = awaiting_reply;
510 } else {
511 current_req = req->next;
512 complete = 1;
513 /* not sure about this */
514 cuda_state = idle;
515 cuda_start();
516 }
517 } else {
518 out_8(&via[SR], req->data[data_index++]);
519 out_8(&via[B], in_8(&via[B]) ^ TACK);
520 }
521 break;
522
523 case reading:
524 *reply_ptr++ = in_8(&via[SR]);
525 if (status == TIP) {
526 /* that's all folks */
527 out_8(&via[B], in_8(&via[B]) | TACK | TIP);
528 cuda_state = read_done;
529 } else {
530 /* assert status == TIP | TREQ */
531 if (status != TIP + TREQ)
532 printk("cuda: state=reading status=%x\n", status);
533 out_8(&via[B], in_8(&via[B]) ^ TACK);
534 }
535 break;
536
537 case read_done:
538 (void)in_8(&via[SR]);
539 if (reading_reply) {
540 req = current_req;
541 req->reply_len = reply_ptr - req->reply;
542 if (req->data[0] == ADB_PACKET) {
543 /* Have to adjust the reply from ADB commands */
544 if (req->reply_len <= 2 || (req->reply[1] & 2) != 0) {
545 /* the 0x2 bit indicates no response */
546 req->reply_len = 0;
547 } else {
548 /* leave just the command and result bytes in the reply */
549 req->reply_len -= 2;
550 memmove(req->reply, req->reply + 2, req->reply_len);
551 }
552 }
553 current_req = req->next;
554 complete = 1;
555 } else {
556 /* This is tricky. We must break the spinlock to call
557 * cuda_input. However, doing so means we might get
558 * re-entered from another CPU getting an interrupt
559 * or calling cuda_poll(). I ended up using the stack
560 * (it's only for 16 bytes) and moving the actual
561 * call to cuda_input to outside of the lock.
562 */
563 ibuf_len = reply_ptr - cuda_rbuf;
564 memcpy(ibuf, cuda_rbuf, ibuf_len);
565 }
566 if (status == TREQ) {
567 out_8(&via[B], in_8(&via[B]) & ~TIP);
568 cuda_state = reading;
569 reply_ptr = cuda_rbuf;
570 reading_reply = 0;
571 } else {
572 cuda_state = idle;
573 cuda_start();
574 }
575 break;
576
577 default:
578 printk("cuda_interrupt: unknown cuda_state %d?\n", cuda_state);
579 }
580 spin_unlock(&cuda_lock);
581 if (complete && req) {
582 void (*done)(struct adb_request *) = req->done;
583 mb();
584 req->complete = 1;
585 /* Here, we assume that if the request has a done member, the
586 * struct request will survive to setting req->complete to 1
587 */
588 if (done)
589 (*done)(req);
590 }
591 if (ibuf_len)
592 cuda_input(ibuf, ibuf_len, regs);
593 return IRQ_HANDLED;
594}
595
596static void
597cuda_input(unsigned char *buf, int nb, struct pt_regs *regs)
598{
599 int i;
600
601 switch (buf[0]) {
602 case ADB_PACKET:
603#ifdef CONFIG_XMON
604 if (nb == 5 && buf[2] == 0x2c) {
605 extern int xmon_wants_key, xmon_adb_keycode;
606 if (xmon_wants_key) {
607 xmon_adb_keycode = buf[3];
608 return;
609 }
610 }
611#endif /* CONFIG_XMON */
612#ifdef CONFIG_ADB
613 adb_input(buf+2, nb-2, regs, buf[1] & 0x40);
614#endif /* CONFIG_ADB */
615 break;
616
617 default:
618 printk("data from cuda (%d bytes):", nb);
619 for (i = 0; i < nb; ++i)
620 printk(" %.2x", buf[i]);
621 printk("\n");
622 }
623}