2 * Device driver for the via-cuda on Apple Powermacs.
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.
9 * Copyright (C) 1996 Paul Mackerras.
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>
22 #include <asm/machdep.h>
24 #include <asm/macintosh.h>
25 #include <asm/macints.h>
26 #include <asm/machw.h>
27 #include <asm/mac_via.h>
30 #include <asm/system.h>
31 #include <linux/init.h>
33 static volatile unsigned char __iomem *via;
34 static DEFINE_SPINLOCK(cuda_lock);
36 /* VIA registers - spaced 0x200 bytes apart */
37 #define RS 0x200 /* skip between registers */
38 #define B 0 /* B-side data */
39 #define A RS /* A-side data */
40 #define DIRB (2*RS) /* B-side direction (1=output) */
41 #define DIRA (3*RS) /* A-side direction (1=output) */
42 #define T1CL (4*RS) /* Timer 1 ctr/latch (low 8 bits) */
43 #define T1CH (5*RS) /* Timer 1 counter (high 8 bits) */
44 #define T1LL (6*RS) /* Timer 1 latch (low 8 bits) */
45 #define T1LH (7*RS) /* Timer 1 latch (high 8 bits) */
46 #define T2CL (8*RS) /* Timer 2 ctr/latch (low 8 bits) */
47 #define T2CH (9*RS) /* Timer 2 counter (high 8 bits) */
48 #define SR (10*RS) /* Shift register */
49 #define ACR (11*RS) /* Auxiliary control register */
50 #define PCR (12*RS) /* Peripheral control register */
51 #define IFR (13*RS) /* Interrupt flag register */
52 #define IER (14*RS) /* Interrupt enable register */
53 #define ANH (15*RS) /* A-side data, no handshake */
55 /* Bits in B data register: all active low */
56 #define TREQ 0x08 /* Transfer request (input) */
57 #define TACK 0x10 /* Transfer acknowledge (output) */
58 #define TIP 0x20 /* Transfer in progress (output) */
61 #define SR_CTRL 0x1c /* Shift register control bits */
62 #define SR_EXT 0x0c /* Shift on external clock */
63 #define SR_OUT 0x10 /* Shift out if 1 */
65 /* Bits in IFR and IER */
66 #define IER_SET 0x80 /* set bits in IER */
67 #define IER_CLR 0 /* clear bits in IER */
68 #define SR_INT 0x04 /* Shift register full/empty */
70 static enum cuda_state {
79 static struct adb_request *current_req;
80 static struct adb_request *last_req;
81 static unsigned char cuda_rbuf[16];
82 static unsigned char *reply_ptr;
83 static int reading_reply;
84 static int data_index;
86 static struct device_node *vias;
88 static int cuda_fully_inited;
91 static int cuda_probe(void);
92 static int cuda_init(void);
93 static int cuda_send_request(struct adb_request *req, int sync);
94 static int cuda_adb_autopoll(int devs);
95 static int cuda_reset_adb_bus(void);
96 #endif /* CONFIG_ADB */
98 static int cuda_init_via(void);
99 static void cuda_start(void);
100 static irqreturn_t cuda_interrupt(int irq, void *arg);
101 static void cuda_input(unsigned char *buf, int nb);
102 void cuda_poll(void);
103 static int cuda_write(struct adb_request *req);
105 int cuda_request(struct adb_request *req,
106 void (*done)(struct adb_request *), int nbytes, ...);
109 struct adb_driver via_cuda_driver = {
118 #endif /* CONFIG_ADB */
121 int __init find_via_cuda(void)
123 struct adb_request req;
130 vias = of_find_node_by_name(NULL, "via-cuda");
134 reg = of_get_property(vias, "reg", NULL);
136 printk(KERN_ERR "via-cuda: No \"reg\" property !\n");
139 taddr = of_translate_address(vias, reg);
141 printk(KERN_ERR "via-cuda: Can't translate address !\n");
144 via = ioremap(taddr, 0x2000);
146 printk(KERN_ERR "via-cuda: Can't map address !\n");
151 sys_ctrler = SYS_CTRLER_CUDA;
153 err = cuda_init_via();
155 printk(KERN_ERR "cuda_init_via() failed\n");
160 /* Clear and enable interrupts, but only on PPC. On 68K it's done */
161 /* for us by the main VIA driver in arch/m68k/mac/via.c */
164 out_8(&via[IFR], 0x7f); /* clear interrupts by writing 1s */
165 out_8(&via[IER], IER_SET|SR_INT); /* enable interrupt from SR */
168 /* enable autopoll */
169 cuda_request(&req, NULL, 3, CUDA_PACKET, CUDA_AUTOPOLL, 1);
170 while (!req.complete)
180 #endif /* CONFIG_PPC */
182 static int __init via_cuda_start(void)
191 #else /* CONFIG_MAC */
192 irq = irq_of_parse_and_map(vias, 0);
194 printk(KERN_ERR "via-cuda: can't map interrupts for %s\n",
198 #endif /* CONFIG_MAP */
200 if (request_irq(irq, cuda_interrupt, 0, "ADB", cuda_interrupt)) {
201 printk(KERN_ERR "via-cuda: can't request irq %d\n", irq);
205 printk("Macintosh CUDA driver v0.5 for Unified ADB.\n");
207 cuda_fully_inited = 1;
211 device_initcall(via_cuda_start);
218 if (sys_ctrler != SYS_CTRLER_CUDA)
221 if (macintosh_config->adb_type != MAC_ADB_CUDA)
236 int err = cuda_init_via();
238 printk(KERN_ERR "cuda_init_via() failed\n");
242 return via_cuda_start();
245 #endif /* CONFIG_ADB */
247 #define WAIT_FOR(cond, what) \
250 for (x = 1000; !(cond); --x) { \
252 printk("Timeout waiting for " what "\n"); \
262 out_8(&via[DIRB], (in_8(&via[DIRB]) | TACK | TIP) & ~TREQ); /* TACK & TIP out */
263 out_8(&via[B], in_8(&via[B]) | TACK | TIP); /* negate them */
264 out_8(&via[ACR] ,(in_8(&via[ACR]) & ~SR_CTRL) | SR_EXT); /* SR data in */
265 (void)in_8(&via[SR]); /* clear any left-over data */
267 out_8(&via[IER], 0x7f); /* disable interrupts from VIA */
268 (void)in_8(&via[IER]);
271 /* delay 4ms and then clear any pending interrupt */
273 (void)in_8(&via[SR]);
274 out_8(&via[IFR], in_8(&via[IFR]) & 0x7f);
276 /* sync with the CUDA - assert TACK without TIP */
277 out_8(&via[B], in_8(&via[B]) & ~TACK);
279 /* wait for the CUDA to assert TREQ in response */
280 WAIT_FOR((in_8(&via[B]) & TREQ) == 0, "CUDA response to sync");
282 /* wait for the interrupt and then clear it */
283 WAIT_FOR(in_8(&via[IFR]) & SR_INT, "CUDA response to sync (2)");
284 (void)in_8(&via[SR]);
285 out_8(&via[IFR], in_8(&via[IFR]) & 0x7f);
287 /* finish the sync by negating TACK */
288 out_8(&via[B], in_8(&via[B]) | TACK);
290 /* wait for the CUDA to negate TREQ and the corresponding interrupt */
291 WAIT_FOR(in_8(&via[B]) & TREQ, "CUDA response to sync (3)");
292 WAIT_FOR(in_8(&via[IFR]) & SR_INT, "CUDA response to sync (4)");
293 (void)in_8(&via[SR]);
294 out_8(&via[IFR], in_8(&via[IFR]) & 0x7f);
295 out_8(&via[B], in_8(&via[B]) | TIP); /* should be unnecessary */
301 /* Send an ADB command */
303 cuda_send_request(struct adb_request *req, int sync)
307 if ((via == NULL) || !cuda_fully_inited) {
312 req->reply_expected = 1;
319 while (!req->complete)
326 /* Enable/disable autopolling */
328 cuda_adb_autopoll(int devs)
330 struct adb_request req;
332 if ((via == NULL) || !cuda_fully_inited)
335 cuda_request(&req, NULL, 3, CUDA_PACKET, CUDA_AUTOPOLL, (devs? 1: 0));
336 while (!req.complete)
341 /* Reset adb bus - how do we do this?? */
343 cuda_reset_adb_bus(void)
345 struct adb_request req;
347 if ((via == NULL) || !cuda_fully_inited)
350 cuda_request(&req, NULL, 2, ADB_PACKET, 0); /* maybe? */
351 while (!req.complete)
355 #endif /* CONFIG_ADB */
356 /* Construct and send a cuda request */
358 cuda_request(struct adb_request *req, void (*done)(struct adb_request *),
369 req->nbytes = nbytes;
371 va_start(list, nbytes);
372 for (i = 0; i < nbytes; ++i)
373 req->data[i] = va_arg(list, int);
375 req->reply_expected = 1;
376 return cuda_write(req);
380 cuda_write(struct adb_request *req)
384 if (req->nbytes < 2 || req->data[0] > CUDA_PACKET) {
393 spin_lock_irqsave(&cuda_lock, flags);
394 if (current_req != 0) {
395 last_req->next = req;
400 if (cuda_state == idle)
403 spin_unlock_irqrestore(&cuda_lock, flags);
411 struct adb_request *req;
413 /* assert cuda_state == idle */
414 /* get the packet to send */
418 if ((in_8(&via[B]) & TREQ) == 0)
419 return; /* a byte is coming in from the CUDA */
421 /* set the shift register to shift out and send a byte */
422 out_8(&via[ACR], in_8(&via[ACR]) | SR_OUT);
423 out_8(&via[SR], req->data[0]);
424 out_8(&via[B], in_8(&via[B]) & ~TIP);
425 cuda_state = sent_first_byte;
433 /* cuda_interrupt only takes a normal lock, we disable
434 * interrupts here to avoid re-entering and thus deadlocking.
435 * An option would be to disable only the IRQ source with
436 * disable_irq(), would that work on m68k ? --BenH
438 local_irq_save(flags);
439 cuda_interrupt(0, NULL);
440 local_irq_restore(flags);
444 cuda_interrupt(int irq, void *arg)
447 struct adb_request *req = NULL;
448 unsigned char ibuf[16];
453 spin_lock(&cuda_lock);
455 virq = in_8(&via[IFR]) & 0x7f;
456 out_8(&via[IFR], virq);
457 if ((virq & SR_INT) == 0) {
458 spin_unlock(&cuda_lock);
462 status = (~in_8(&via[B]) & (TIP|TREQ)) | (in_8(&via[ACR]) & SR_OUT);
463 /* printk("cuda_interrupt: state=%d status=%x\n", cuda_state, status); */
464 switch (cuda_state) {
466 /* CUDA has sent us the first byte of data - unsolicited */
468 printk("cuda: state=idle, status=%x\n", status);
469 (void)in_8(&via[SR]);
470 out_8(&via[B], in_8(&via[B]) & ~TIP);
471 cuda_state = reading;
472 reply_ptr = cuda_rbuf;
477 /* CUDA has sent us the first byte of data of a reply */
479 printk("cuda: state=awaiting_reply, status=%x\n", status);
480 (void)in_8(&via[SR]);
481 out_8(&via[B], in_8(&via[B]) & ~TIP);
482 cuda_state = reading;
483 reply_ptr = current_req->reply;
487 case sent_first_byte:
488 if (status == TREQ + TIP + SR_OUT) {
490 out_8(&via[ACR], in_8(&via[ACR]) & ~SR_OUT);
491 (void)in_8(&via[SR]);
492 out_8(&via[B], in_8(&via[B]) | TIP | TACK);
495 /* assert status == TIP + SR_OUT */
496 if (status != TIP + SR_OUT)
497 printk("cuda: state=sent_first_byte status=%x\n", status);
498 out_8(&via[SR], current_req->data[1]);
499 out_8(&via[B], in_8(&via[B]) ^ TACK);
501 cuda_state = sending;
507 if (data_index >= req->nbytes) {
508 out_8(&via[ACR], in_8(&via[ACR]) & ~SR_OUT);
509 (void)in_8(&via[SR]);
510 out_8(&via[B], in_8(&via[B]) | TACK | TIP);
512 if (req->reply_expected) {
513 cuda_state = awaiting_reply;
515 current_req = req->next;
517 /* not sure about this */
522 out_8(&via[SR], req->data[data_index++]);
523 out_8(&via[B], in_8(&via[B]) ^ TACK);
528 *reply_ptr++ = in_8(&via[SR]);
530 /* that's all folks */
531 out_8(&via[B], in_8(&via[B]) | TACK | TIP);
532 cuda_state = read_done;
534 /* assert status == TIP | TREQ */
535 if (status != TIP + TREQ)
536 printk("cuda: state=reading status=%x\n", status);
537 out_8(&via[B], in_8(&via[B]) ^ TACK);
542 (void)in_8(&via[SR]);
545 req->reply_len = reply_ptr - req->reply;
546 if (req->data[0] == ADB_PACKET) {
547 /* Have to adjust the reply from ADB commands */
548 if (req->reply_len <= 2 || (req->reply[1] & 2) != 0) {
549 /* the 0x2 bit indicates no response */
552 /* leave just the command and result bytes in the reply */
554 memmove(req->reply, req->reply + 2, req->reply_len);
557 current_req = req->next;
560 /* This is tricky. We must break the spinlock to call
561 * cuda_input. However, doing so means we might get
562 * re-entered from another CPU getting an interrupt
563 * or calling cuda_poll(). I ended up using the stack
564 * (it's only for 16 bytes) and moving the actual
565 * call to cuda_input to outside of the lock.
567 ibuf_len = reply_ptr - cuda_rbuf;
568 memcpy(ibuf, cuda_rbuf, ibuf_len);
570 if (status == TREQ) {
571 out_8(&via[B], in_8(&via[B]) & ~TIP);
572 cuda_state = reading;
573 reply_ptr = cuda_rbuf;
582 printk("cuda_interrupt: unknown cuda_state %d?\n", cuda_state);
584 spin_unlock(&cuda_lock);
585 if (complete && req) {
586 void (*done)(struct adb_request *) = req->done;
589 /* Here, we assume that if the request has a done member, the
590 * struct request will survive to setting req->complete to 1
596 cuda_input(ibuf, ibuf_len);
601 cuda_input(unsigned char *buf, int nb)
608 if (nb == 5 && buf[2] == 0x2c) {
609 extern int xmon_wants_key, xmon_adb_keycode;
610 if (xmon_wants_key) {
611 xmon_adb_keycode = buf[3];
615 #endif /* CONFIG_XMON */
617 adb_input(buf+2, nb-2, buf[1] & 0x40);
618 #endif /* CONFIG_ADB */
622 printk("data from cuda (%d bytes):", nb);
623 for (i = 0; i < nb; ++i)
624 printk(" %.2x", buf[i]);