1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* |
3 | * Device driver for the Cuda and Egret system controllers found on PowerMacs |
4 | * and 68k Macs. |
5 | * |
6 | * The Cuda or Egret is a 6805 microcontroller interfaced to the 6522 VIA. |
7 | * This MCU controls system power, Parameter RAM, Real Time Clock and the |
8 | * Apple Desktop Bus (ADB) that connects to the keyboard and mouse. |
9 | * |
10 | * Copyright (C) 1996 Paul Mackerras. |
11 | */ |
12 | #include <linux/stdarg.h> |
13 | #include <linux/types.h> |
14 | #include <linux/errno.h> |
15 | #include <linux/kernel.h> |
16 | #include <linux/delay.h> |
17 | #include <linux/adb.h> |
18 | #include <linux/cuda.h> |
19 | #include <linux/spinlock.h> |
20 | #include <linux/interrupt.h> |
21 | #include <linux/of_address.h> |
22 | #include <linux/of_irq.h> |
23 | |
24 | #ifdef CONFIG_PPC |
25 | #include <asm/machdep.h> |
26 | #include <asm/pmac_feature.h> |
27 | #else |
28 | #include <asm/macintosh.h> |
29 | #include <asm/macints.h> |
30 | #include <asm/mac_via.h> |
31 | #endif |
32 | #include <asm/io.h> |
33 | #include <linux/init.h> |
34 | |
35 | static volatile unsigned char __iomem *via; |
36 | static DEFINE_SPINLOCK(cuda_lock); |
37 | |
38 | /* VIA registers - spaced 0x200 bytes apart */ |
39 | #define RS 0x200 /* skip between registers */ |
40 | #define B 0 /* B-side data */ |
41 | #define A RS /* A-side data */ |
42 | #define DIRB (2*RS) /* B-side direction (1=output) */ |
43 | #define DIRA (3*RS) /* A-side direction (1=output) */ |
44 | #define T1CL (4*RS) /* Timer 1 ctr/latch (low 8 bits) */ |
45 | #define T1CH (5*RS) /* Timer 1 counter (high 8 bits) */ |
46 | #define T1LL (6*RS) /* Timer 1 latch (low 8 bits) */ |
47 | #define T1LH (7*RS) /* Timer 1 latch (high 8 bits) */ |
48 | #define T2CL (8*RS) /* Timer 2 ctr/latch (low 8 bits) */ |
49 | #define T2CH (9*RS) /* Timer 2 counter (high 8 bits) */ |
50 | #define SR (10*RS) /* Shift register */ |
51 | #define ACR (11*RS) /* Auxiliary control register */ |
52 | #define PCR (12*RS) /* Peripheral control register */ |
53 | #define IFR (13*RS) /* Interrupt flag register */ |
54 | #define IER (14*RS) /* Interrupt enable register */ |
55 | #define ANH (15*RS) /* A-side data, no handshake */ |
56 | |
57 | /* |
58 | * When the Cuda design replaced the Egret, some signal names and |
59 | * logic sense changed. They all serve the same purposes, however. |
60 | * |
61 | * VIA pin | Egret pin |
62 | * ----------------+------------------------------------------ |
63 | * PB3 (input) | Transceiver session (active low) |
64 | * PB4 (output) | VIA full (active high) |
65 | * PB5 (output) | System session (active high) |
66 | * |
67 | * VIA pin | Cuda pin |
68 | * ----------------+------------------------------------------ |
69 | * PB3 (input) | Transfer request (active low) |
70 | * PB4 (output) | Byte acknowledge (active low) |
71 | * PB5 (output) | Transfer in progress (active low) |
72 | */ |
73 | |
74 | /* Bits in Port B data register */ |
75 | #define TREQ 0x08 /* Transfer request */ |
76 | #define TACK 0x10 /* Transfer acknowledge */ |
77 | #define TIP 0x20 /* Transfer in progress */ |
78 | |
79 | /* Bits in ACR */ |
80 | #define SR_CTRL 0x1c /* Shift register control bits */ |
81 | #define SR_EXT 0x0c /* Shift on external clock */ |
82 | #define SR_OUT 0x10 /* Shift out if 1 */ |
83 | |
84 | /* Bits in IFR and IER */ |
85 | #define IER_SET 0x80 /* set bits in IER */ |
86 | #define IER_CLR 0 /* clear bits in IER */ |
87 | #define SR_INT 0x04 /* Shift register full/empty */ |
88 | |
89 | /* Duration of byte acknowledgement pulse (us) */ |
90 | #define EGRET_TACK_ASSERTED_DELAY 300 |
91 | #define EGRET_TACK_NEGATED_DELAY 400 |
92 | |
93 | /* Interval from interrupt to start of session (us) */ |
94 | #define EGRET_SESSION_DELAY 450 |
95 | |
96 | #ifdef CONFIG_PPC |
97 | #define mcu_is_egret false |
98 | #else |
99 | static bool mcu_is_egret; |
100 | #endif |
101 | |
102 | static inline bool TREQ_asserted(u8 portb) |
103 | { |
104 | return !(portb & TREQ); |
105 | } |
106 | |
107 | static inline void assert_TIP(void) |
108 | { |
109 | if (mcu_is_egret) { |
110 | udelay(EGRET_SESSION_DELAY); |
111 | out_8(&via[B], in_8(&via[B]) | TIP); |
112 | } else |
113 | out_8(&via[B], in_8(&via[B]) & ~TIP); |
114 | } |
115 | |
116 | static inline void assert_TIP_and_TACK(void) |
117 | { |
118 | if (mcu_is_egret) { |
119 | udelay(EGRET_SESSION_DELAY); |
120 | out_8(&via[B], in_8(&via[B]) | TIP | TACK); |
121 | } else |
122 | out_8(&via[B], in_8(&via[B]) & ~(TIP | TACK)); |
123 | } |
124 | |
125 | static inline void assert_TACK(void) |
126 | { |
127 | if (mcu_is_egret) { |
128 | udelay(EGRET_TACK_NEGATED_DELAY); |
129 | out_8(&via[B], in_8(&via[B]) | TACK); |
130 | } else |
131 | out_8(&via[B], in_8(&via[B]) & ~TACK); |
132 | } |
133 | |
134 | static inline void toggle_TACK(void) |
135 | { |
136 | out_8(&via[B], in_8(&via[B]) ^ TACK); |
137 | } |
138 | |
139 | static inline void negate_TACK(void) |
140 | { |
141 | if (mcu_is_egret) { |
142 | udelay(EGRET_TACK_ASSERTED_DELAY); |
143 | out_8(&via[B], in_8(&via[B]) & ~TACK); |
144 | } else |
145 | out_8(&via[B], in_8(&via[B]) | TACK); |
146 | } |
147 | |
148 | static inline void negate_TIP_and_TACK(void) |
149 | { |
150 | if (mcu_is_egret) { |
151 | udelay(EGRET_TACK_ASSERTED_DELAY); |
152 | out_8(&via[B], in_8(&via[B]) & ~(TIP | TACK)); |
153 | } else |
154 | out_8(&via[B], in_8(&via[B]) | TIP | TACK); |
155 | } |
156 | |
157 | static enum cuda_state { |
158 | idle, |
159 | sent_first_byte, |
160 | sending, |
161 | reading, |
162 | read_done, |
163 | awaiting_reply |
164 | } cuda_state; |
165 | |
166 | static struct adb_request *current_req; |
167 | static struct adb_request *last_req; |
168 | static unsigned char cuda_rbuf[16]; |
169 | static unsigned char *reply_ptr; |
170 | static int reading_reply; |
171 | static int data_index; |
172 | static int cuda_irq; |
173 | #ifdef CONFIG_PPC |
174 | static struct device_node *vias; |
175 | #endif |
176 | static int cuda_fully_inited; |
177 | |
178 | #ifdef CONFIG_ADB |
179 | static int cuda_probe(void); |
180 | static int cuda_send_request(struct adb_request *req, int sync); |
181 | static int cuda_adb_autopoll(int devs); |
182 | static int cuda_reset_adb_bus(void); |
183 | #endif /* CONFIG_ADB */ |
184 | |
185 | static int cuda_init_via(void); |
186 | static void cuda_start(void); |
187 | static irqreturn_t cuda_interrupt(int irq, void *arg); |
188 | static void cuda_input(unsigned char *buf, int nb); |
189 | void cuda_poll(void); |
190 | static int cuda_write(struct adb_request *req); |
191 | |
192 | int cuda_request(struct adb_request *req, |
193 | void (*done)(struct adb_request *), int nbytes, ...); |
194 | |
195 | #ifdef CONFIG_ADB |
196 | struct adb_driver via_cuda_driver = { |
197 | .name = "CUDA" , |
198 | .probe = cuda_probe, |
199 | .send_request = cuda_send_request, |
200 | .autopoll = cuda_adb_autopoll, |
201 | .poll = cuda_poll, |
202 | .reset_bus = cuda_reset_adb_bus, |
203 | }; |
204 | #endif /* CONFIG_ADB */ |
205 | |
206 | #ifdef CONFIG_MAC |
207 | int __init find_via_cuda(void) |
208 | { |
209 | struct adb_request req; |
210 | int err; |
211 | |
212 | if (macintosh_config->adb_type != MAC_ADB_CUDA && |
213 | macintosh_config->adb_type != MAC_ADB_EGRET) |
214 | return 0; |
215 | |
216 | via = via1; |
217 | cuda_state = idle; |
218 | mcu_is_egret = macintosh_config->adb_type == MAC_ADB_EGRET; |
219 | |
220 | err = cuda_init_via(); |
221 | if (err) { |
222 | printk(KERN_ERR "cuda_init_via() failed\n" ); |
223 | via = NULL; |
224 | return 0; |
225 | } |
226 | |
227 | /* enable autopoll */ |
228 | cuda_request(&req, NULL, 3, CUDA_PACKET, CUDA_AUTOPOLL, 1); |
229 | while (!req.complete) |
230 | cuda_poll(); |
231 | |
232 | return 1; |
233 | } |
234 | #else |
235 | int __init find_via_cuda(void) |
236 | { |
237 | struct adb_request req; |
238 | struct resource res; |
239 | int err; |
240 | |
241 | if (vias) |
242 | return 1; |
243 | vias = of_find_node_by_name(NULL, name: "via-cuda" ); |
244 | if (!vias) |
245 | return 0; |
246 | |
247 | err = of_address_to_resource(dev: vias, index: 0, r: &res); |
248 | if (err) { |
249 | printk(KERN_ERR "via-cuda: Error getting \"reg\" property !\n" ); |
250 | goto fail; |
251 | } |
252 | via = ioremap(offset: res.start, size: 0x2000); |
253 | if (via == NULL) { |
254 | printk(KERN_ERR "via-cuda: Can't map address !\n" ); |
255 | goto fail; |
256 | } |
257 | |
258 | cuda_state = idle; |
259 | sys_ctrler = SYS_CTRLER_CUDA; |
260 | |
261 | err = cuda_init_via(); |
262 | if (err) { |
263 | printk(KERN_ERR "cuda_init_via() failed\n" ); |
264 | via = NULL; |
265 | return 0; |
266 | } |
267 | |
268 | /* Clear and enable interrupts, but only on PPC. On 68K it's done */ |
269 | /* for us by the main VIA driver in arch/m68k/mac/via.c */ |
270 | |
271 | out_8(&via[IFR], 0x7f); /* clear interrupts by writing 1s */ |
272 | out_8(&via[IER], IER_SET|SR_INT); /* enable interrupt from SR */ |
273 | |
274 | /* enable autopoll */ |
275 | cuda_request(req: &req, NULL, nbytes: 3, CUDA_PACKET, CUDA_AUTOPOLL, 1); |
276 | while (!req.complete) |
277 | cuda_poll(); |
278 | |
279 | return 1; |
280 | |
281 | fail: |
282 | of_node_put(node: vias); |
283 | vias = NULL; |
284 | return 0; |
285 | } |
286 | #endif /* !defined CONFIG_MAC */ |
287 | |
288 | static int __init via_cuda_start(void) |
289 | { |
290 | if (via == NULL) |
291 | return -ENODEV; |
292 | |
293 | #ifdef CONFIG_MAC |
294 | cuda_irq = IRQ_MAC_ADB; |
295 | #else |
296 | cuda_irq = irq_of_parse_and_map(node: vias, index: 0); |
297 | if (!cuda_irq) { |
298 | printk(KERN_ERR "via-cuda: can't map interrupts for %pOF\n" , |
299 | vias); |
300 | return -ENODEV; |
301 | } |
302 | #endif |
303 | |
304 | if (request_irq(irq: cuda_irq, handler: cuda_interrupt, flags: 0, name: "ADB" , dev: cuda_interrupt)) { |
305 | printk(KERN_ERR "via-cuda: can't request irq %d\n" , cuda_irq); |
306 | return -EAGAIN; |
307 | } |
308 | |
309 | pr_info("Macintosh Cuda and Egret driver.\n" ); |
310 | |
311 | cuda_fully_inited = 1; |
312 | return 0; |
313 | } |
314 | |
315 | device_initcall(via_cuda_start); |
316 | |
317 | #ifdef CONFIG_ADB |
318 | static int |
319 | cuda_probe(void) |
320 | { |
321 | #ifdef CONFIG_PPC |
322 | if (sys_ctrler != SYS_CTRLER_CUDA) |
323 | return -ENODEV; |
324 | #else |
325 | if (macintosh_config->adb_type != MAC_ADB_CUDA && |
326 | macintosh_config->adb_type != MAC_ADB_EGRET) |
327 | return -ENODEV; |
328 | #endif |
329 | if (via == NULL) |
330 | return -ENODEV; |
331 | return 0; |
332 | } |
333 | #endif /* CONFIG_ADB */ |
334 | |
335 | static int __init sync_egret(void) |
336 | { |
337 | if (TREQ_asserted(portb: in_8(&via[B]))) { |
338 | /* Complete the inbound transfer */ |
339 | assert_TIP_and_TACK(); |
340 | while (1) { |
341 | negate_TACK(); |
342 | mdelay(1); |
343 | (void)in_8(&via[SR]); |
344 | assert_TACK(); |
345 | if (!TREQ_asserted(portb: in_8(&via[B]))) |
346 | break; |
347 | } |
348 | negate_TIP_and_TACK(); |
349 | } else if (in_8(&via[B]) & TIP) { |
350 | /* Terminate the outbound transfer */ |
351 | negate_TACK(); |
352 | assert_TACK(); |
353 | mdelay(1); |
354 | negate_TIP_and_TACK(); |
355 | } |
356 | /* Clear shift register interrupt */ |
357 | if (in_8(&via[IFR]) & SR_INT) |
358 | (void)in_8(&via[SR]); |
359 | return 0; |
360 | } |
361 | |
362 | #define WAIT_FOR(cond, what) \ |
363 | do { \ |
364 | int x; \ |
365 | for (x = 1000; !(cond); --x) { \ |
366 | if (x == 0) { \ |
367 | pr_err("Timeout waiting for " what "\n"); \ |
368 | return -ENXIO; \ |
369 | } \ |
370 | udelay(100); \ |
371 | } \ |
372 | } while (0) |
373 | |
374 | static int |
375 | __init cuda_init_via(void) |
376 | { |
377 | #ifdef CONFIG_PPC |
378 | out_8(&via[IER], 0x7f); /* disable interrupts from VIA */ |
379 | (void)in_8(&via[IER]); |
380 | #else |
381 | out_8(&via[IER], SR_INT); /* disable SR interrupt from VIA */ |
382 | #endif |
383 | |
384 | out_8(&via[DIRB], (in_8(&via[DIRB]) | TACK | TIP) & ~TREQ); /* TACK & TIP out */ |
385 | out_8(&via[ACR], (in_8(&via[ACR]) & ~SR_CTRL) | SR_EXT); /* SR data in */ |
386 | (void)in_8(&via[SR]); /* clear any left-over data */ |
387 | |
388 | if (mcu_is_egret) |
389 | return sync_egret(); |
390 | |
391 | negate_TIP_and_TACK(); |
392 | |
393 | /* delay 4ms and then clear any pending interrupt */ |
394 | mdelay(4); |
395 | (void)in_8(&via[SR]); |
396 | out_8(&via[IFR], SR_INT); |
397 | |
398 | /* sync with the CUDA - assert TACK without TIP */ |
399 | assert_TACK(); |
400 | |
401 | /* wait for the CUDA to assert TREQ in response */ |
402 | WAIT_FOR(TREQ_asserted(in_8(&via[B])), "CUDA response to sync" ); |
403 | |
404 | /* wait for the interrupt and then clear it */ |
405 | WAIT_FOR(in_8(&via[IFR]) & SR_INT, "CUDA response to sync (2)" ); |
406 | (void)in_8(&via[SR]); |
407 | out_8(&via[IFR], SR_INT); |
408 | |
409 | /* finish the sync by negating TACK */ |
410 | negate_TACK(); |
411 | |
412 | /* wait for the CUDA to negate TREQ and the corresponding interrupt */ |
413 | WAIT_FOR(!TREQ_asserted(in_8(&via[B])), "CUDA response to sync (3)" ); |
414 | WAIT_FOR(in_8(&via[IFR]) & SR_INT, "CUDA response to sync (4)" ); |
415 | (void)in_8(&via[SR]); |
416 | out_8(&via[IFR], SR_INT); |
417 | |
418 | return 0; |
419 | } |
420 | |
421 | #ifdef CONFIG_ADB |
422 | /* Send an ADB command */ |
423 | static int |
424 | cuda_send_request(struct adb_request *req, int sync) |
425 | { |
426 | int i; |
427 | |
428 | if ((via == NULL) || !cuda_fully_inited) { |
429 | req->complete = 1; |
430 | return -ENXIO; |
431 | } |
432 | |
433 | req->reply_expected = 1; |
434 | |
435 | i = cuda_write(req); |
436 | if (i) |
437 | return i; |
438 | |
439 | if (sync) { |
440 | while (!req->complete) |
441 | cuda_poll(); |
442 | } |
443 | return 0; |
444 | } |
445 | |
446 | |
447 | /* Enable/disable autopolling */ |
448 | static int |
449 | cuda_adb_autopoll(int devs) |
450 | { |
451 | struct adb_request req; |
452 | |
453 | if ((via == NULL) || !cuda_fully_inited) |
454 | return -ENXIO; |
455 | |
456 | cuda_request(&req, NULL, 3, CUDA_PACKET, CUDA_AUTOPOLL, (devs? 1: 0)); |
457 | while (!req.complete) |
458 | cuda_poll(); |
459 | return 0; |
460 | } |
461 | |
462 | /* Reset adb bus - how do we do this?? */ |
463 | static int |
464 | cuda_reset_adb_bus(void) |
465 | { |
466 | struct adb_request req; |
467 | |
468 | if ((via == NULL) || !cuda_fully_inited) |
469 | return -ENXIO; |
470 | |
471 | cuda_request(&req, NULL, 2, ADB_PACKET, 0); /* maybe? */ |
472 | while (!req.complete) |
473 | cuda_poll(); |
474 | return 0; |
475 | } |
476 | #endif /* CONFIG_ADB */ |
477 | |
478 | /* Construct and send a cuda request */ |
479 | int |
480 | cuda_request(struct adb_request *req, void (*done)(struct adb_request *), |
481 | int nbytes, ...) |
482 | { |
483 | va_list list; |
484 | int i; |
485 | |
486 | if (via == NULL) { |
487 | req->complete = 1; |
488 | return -ENXIO; |
489 | } |
490 | |
491 | req->nbytes = nbytes; |
492 | req->done = done; |
493 | va_start(list, nbytes); |
494 | for (i = 0; i < nbytes; ++i) |
495 | req->data[i] = va_arg(list, int); |
496 | va_end(list); |
497 | req->reply_expected = 1; |
498 | return cuda_write(req); |
499 | } |
500 | EXPORT_SYMBOL(cuda_request); |
501 | |
502 | static int |
503 | cuda_write(struct adb_request *req) |
504 | { |
505 | unsigned long flags; |
506 | |
507 | if (req->nbytes < 2 || req->data[0] > CUDA_PACKET) { |
508 | req->complete = 1; |
509 | return -EINVAL; |
510 | } |
511 | req->next = NULL; |
512 | req->sent = 0; |
513 | req->complete = 0; |
514 | req->reply_len = 0; |
515 | |
516 | spin_lock_irqsave(&cuda_lock, flags); |
517 | if (current_req) { |
518 | last_req->next = req; |
519 | last_req = req; |
520 | } else { |
521 | current_req = req; |
522 | last_req = req; |
523 | if (cuda_state == idle) |
524 | cuda_start(); |
525 | } |
526 | spin_unlock_irqrestore(lock: &cuda_lock, flags); |
527 | |
528 | return 0; |
529 | } |
530 | |
531 | static void |
532 | cuda_start(void) |
533 | { |
534 | /* assert cuda_state == idle */ |
535 | if (current_req == NULL) |
536 | return; |
537 | data_index = 0; |
538 | if (TREQ_asserted(portb: in_8(&via[B]))) |
539 | return; /* a byte is coming in from the CUDA */ |
540 | |
541 | /* set the shift register to shift out and send a byte */ |
542 | out_8(&via[ACR], in_8(&via[ACR]) | SR_OUT); |
543 | out_8(&via[SR], current_req->data[data_index++]); |
544 | if (mcu_is_egret) |
545 | assert_TIP_and_TACK(); |
546 | else |
547 | assert_TIP(); |
548 | cuda_state = sent_first_byte; |
549 | } |
550 | |
551 | void |
552 | cuda_poll(void) |
553 | { |
554 | cuda_interrupt(irq: 0, NULL); |
555 | } |
556 | EXPORT_SYMBOL(cuda_poll); |
557 | |
558 | #define ARRAY_FULL(a, p) ((p) - (a) == ARRAY_SIZE(a)) |
559 | |
560 | static irqreturn_t |
561 | cuda_interrupt(int irq, void *arg) |
562 | { |
563 | unsigned long flags; |
564 | u8 status; |
565 | struct adb_request *req = NULL; |
566 | unsigned char ibuf[16]; |
567 | int ibuf_len = 0; |
568 | int complete = 0; |
569 | bool full; |
570 | |
571 | spin_lock_irqsave(&cuda_lock, flags); |
572 | |
573 | /* On powermacs, this handler is registered for the VIA IRQ. But they use |
574 | * just the shift register IRQ -- other VIA interrupt sources are disabled. |
575 | * On m68k macs, the VIA IRQ sources are dispatched individually. Unless |
576 | * we are polling, the shift register IRQ flag has already been cleared. |
577 | */ |
578 | |
579 | #ifdef CONFIG_MAC |
580 | if (!arg) |
581 | #endif |
582 | { |
583 | if ((in_8(&via[IFR]) & SR_INT) == 0) { |
584 | spin_unlock_irqrestore(lock: &cuda_lock, flags); |
585 | return IRQ_NONE; |
586 | } else { |
587 | out_8(&via[IFR], SR_INT); |
588 | } |
589 | } |
590 | |
591 | status = in_8(&via[B]) & (TIP | TACK | TREQ); |
592 | |
593 | switch (cuda_state) { |
594 | case idle: |
595 | /* System controller has unsolicited data for us */ |
596 | (void)in_8(&via[SR]); |
597 | idle_state: |
598 | assert_TIP(); |
599 | cuda_state = reading; |
600 | reply_ptr = cuda_rbuf; |
601 | reading_reply = 0; |
602 | break; |
603 | |
604 | case awaiting_reply: |
605 | /* System controller has reply data for us */ |
606 | (void)in_8(&via[SR]); |
607 | assert_TIP(); |
608 | cuda_state = reading; |
609 | reply_ptr = current_req->reply; |
610 | reading_reply = 1; |
611 | break; |
612 | |
613 | case sent_first_byte: |
614 | if (TREQ_asserted(portb: status)) { |
615 | /* collision */ |
616 | out_8(&via[ACR], in_8(&via[ACR]) & ~SR_OUT); |
617 | (void)in_8(&via[SR]); |
618 | negate_TIP_and_TACK(); |
619 | cuda_state = idle; |
620 | /* Egret does not raise an "aborted" interrupt */ |
621 | if (mcu_is_egret) |
622 | goto idle_state; |
623 | } else { |
624 | out_8(&via[SR], current_req->data[data_index++]); |
625 | toggle_TACK(); |
626 | if (mcu_is_egret) |
627 | assert_TACK(); |
628 | cuda_state = sending; |
629 | } |
630 | break; |
631 | |
632 | case sending: |
633 | req = current_req; |
634 | if (data_index >= req->nbytes) { |
635 | out_8(&via[ACR], in_8(&via[ACR]) & ~SR_OUT); |
636 | (void)in_8(&via[SR]); |
637 | negate_TIP_and_TACK(); |
638 | req->sent = 1; |
639 | if (req->reply_expected) { |
640 | cuda_state = awaiting_reply; |
641 | } else { |
642 | current_req = req->next; |
643 | complete = 1; |
644 | /* not sure about this */ |
645 | cuda_state = idle; |
646 | cuda_start(); |
647 | } |
648 | } else { |
649 | out_8(&via[SR], req->data[data_index++]); |
650 | toggle_TACK(); |
651 | if (mcu_is_egret) |
652 | assert_TACK(); |
653 | } |
654 | break; |
655 | |
656 | case reading: |
657 | full = reading_reply ? ARRAY_FULL(current_req->reply, reply_ptr) |
658 | : ARRAY_FULL(cuda_rbuf, reply_ptr); |
659 | if (full) |
660 | (void)in_8(&via[SR]); |
661 | else |
662 | *reply_ptr++ = in_8(&via[SR]); |
663 | if (!TREQ_asserted(portb: status) || full) { |
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(portb: 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(lock: &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(buf: ibuf, nb: 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, prefix_str: "cuda_input: " , prefix_type: DUMP_PREFIX_NONE, rowsize: 32, groupsize: 1, |
765 | buf, len: nb, ascii: false); |
766 | } |
767 | } |
768 | |
769 | /* Offset between Unix time (1970-based) and Mac time (1904-based) */ |
770 | #define RTC_OFFSET 2082844800 |
771 | |
772 | time64_t cuda_get_time(void) |
773 | { |
774 | struct adb_request req; |
775 | u32 now; |
776 | |
777 | if (cuda_request(&req, NULL, 2, CUDA_PACKET, CUDA_GET_TIME) < 0) |
778 | return 0; |
779 | while (!req.complete) |
780 | cuda_poll(); |
781 | if (req.reply_len != 7) |
782 | pr_err("%s: got %d byte reply\n" , __func__, req.reply_len); |
783 | now = (req.reply[3] << 24) + (req.reply[4] << 16) + |
784 | (req.reply[5] << 8) + req.reply[6]; |
785 | return (time64_t)now - RTC_OFFSET; |
786 | } |
787 | |
788 | int cuda_set_rtc_time(struct rtc_time *tm) |
789 | { |
790 | u32 now; |
791 | struct adb_request req; |
792 | |
793 | now = lower_32_bits(rtc_tm_to_time64(tm) + RTC_OFFSET); |
794 | if (cuda_request(&req, NULL, 6, CUDA_PACKET, CUDA_SET_TIME, |
795 | now >> 24, now >> 16, now >> 8, now) < 0) |
796 | return -ENXIO; |
797 | while (!req.complete) |
798 | cuda_poll(); |
799 | if ((req.reply_len != 3) && (req.reply_len != 7)) |
800 | pr_err("%s: got %d byte reply\n" , __func__, req.reply_len); |
801 | return 0; |
802 | } |
803 | |