1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* |
3 | * 3215 line mode terminal driver. |
4 | * |
5 | * Copyright IBM Corp. 1999, 2009 |
6 | * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com> |
7 | * |
8 | * Updated: |
9 | * Aug-2000: Added tab support |
10 | * Dan Morrison, IBM Corporation <dmorriso@cse.buffalo.edu> |
11 | */ |
12 | |
13 | #include <linux/types.h> |
14 | #include <linux/kdev_t.h> |
15 | #include <linux/tty.h> |
16 | #include <linux/tty_flip.h> |
17 | #include <linux/vt_kern.h> |
18 | #include <linux/init.h> |
19 | #include <linux/console.h> |
20 | #include <linux/interrupt.h> |
21 | #include <linux/err.h> |
22 | #include <linux/panic_notifier.h> |
23 | #include <linux/reboot.h> |
24 | #include <linux/serial.h> /* ASYNC_* flags */ |
25 | #include <linux/slab.h> |
26 | #include <asm/ccwdev.h> |
27 | #include <asm/cio.h> |
28 | #include <linux/io.h> |
29 | #include <asm/ebcdic.h> |
30 | #include <linux/uaccess.h> |
31 | #include <asm/delay.h> |
32 | #include <asm/cpcmd.h> |
33 | #include <asm/setup.h> |
34 | |
35 | #include "ctrlchar.h" |
36 | |
37 | #define NR_3215 1 |
38 | #define NR_3215_REQ (4*NR_3215) |
39 | #define RAW3215_BUFFER_SIZE 65536 /* output buffer size */ |
40 | #define RAW3215_INBUF_SIZE 256 /* input buffer size */ |
41 | #define RAW3215_MIN_SPACE 128 /* minimum free space for wakeup */ |
42 | #define RAW3215_MIN_WRITE 1024 /* min. length for immediate output */ |
43 | #define RAW3215_MAX_BYTES 3968 /* max. bytes to write with one ssch */ |
44 | #define RAW3215_MAX_NEWLINE 50 /* max. lines to write with one ssch */ |
45 | #define RAW3215_NR_CCWS 3 |
46 | #define RAW3215_TIMEOUT HZ/10 /* time for delayed output */ |
47 | |
48 | #define RAW3215_FIXED 1 /* 3215 console device is not be freed */ |
49 | #define RAW3215_WORKING 4 /* set if a request is being worked on */ |
50 | #define RAW3215_THROTTLED 8 /* set if reading is disabled */ |
51 | #define RAW3215_STOPPED 16 /* set if writing is disabled */ |
52 | #define RAW3215_TIMER_RUNS 64 /* set if the output delay timer is on */ |
53 | #define RAW3215_FLUSHING 128 /* set to flush buffer (no delay) */ |
54 | |
55 | #define TAB_STOP_SIZE 8 /* tab stop size */ |
56 | |
57 | /* |
58 | * Request types for a 3215 device |
59 | */ |
60 | enum raw3215_type { |
61 | RAW3215_FREE, RAW3215_READ, RAW3215_WRITE |
62 | }; |
63 | |
64 | /* |
65 | * Request structure for a 3215 device |
66 | */ |
67 | struct raw3215_req { |
68 | enum raw3215_type type; /* type of the request */ |
69 | int start, len; /* start index & len in output buffer */ |
70 | int delayable; /* indication to wait for more data */ |
71 | int residual; /* residual count for read request */ |
72 | struct ccw1 ccws[RAW3215_NR_CCWS]; /* space for the channel program */ |
73 | struct raw3215_info *info; /* pointer to main structure */ |
74 | struct raw3215_req *next; /* pointer to next request */ |
75 | } __attribute__ ((aligned(8))); |
76 | |
77 | struct raw3215_info { |
78 | struct tty_port port; |
79 | struct ccw_device *cdev; /* device for tty driver */ |
80 | spinlock_t *lock; /* pointer to irq lock */ |
81 | int flags; /* state flags */ |
82 | u8 *buffer; /* pointer to output buffer */ |
83 | u8 *inbuf; /* pointer to input buffer */ |
84 | int head; /* first free byte in output buffer */ |
85 | int count; /* number of bytes in output buffer */ |
86 | int written; /* number of bytes in write requests */ |
87 | struct raw3215_req *queued_read; /* pointer to queued read requests */ |
88 | struct raw3215_req *queued_write;/* pointer to queued write requests */ |
89 | wait_queue_head_t empty_wait; /* wait queue for flushing */ |
90 | struct timer_list timer; /* timer for delayed output */ |
91 | int line_pos; /* position on the line (for tabs) */ |
92 | }; |
93 | |
94 | /* array of 3215 devices structures */ |
95 | static struct raw3215_info *raw3215[NR_3215]; |
96 | /* spinlock to protect the raw3215 array */ |
97 | static DEFINE_SPINLOCK(raw3215_device_lock); |
98 | /* list of free request structures */ |
99 | static struct raw3215_req *raw3215_freelist; |
100 | /* spinlock to protect free list */ |
101 | static DEFINE_SPINLOCK(raw3215_freelist_lock); |
102 | |
103 | static struct tty_driver *tty3215_driver; |
104 | static bool con3215_drop = true; |
105 | |
106 | /* |
107 | * Get a request structure from the free list |
108 | */ |
109 | static inline struct raw3215_req *raw3215_alloc_req(void) |
110 | { |
111 | struct raw3215_req *req; |
112 | unsigned long flags; |
113 | |
114 | spin_lock_irqsave(&raw3215_freelist_lock, flags); |
115 | req = raw3215_freelist; |
116 | raw3215_freelist = req->next; |
117 | spin_unlock_irqrestore(lock: &raw3215_freelist_lock, flags); |
118 | return req; |
119 | } |
120 | |
121 | /* |
122 | * Put a request structure back to the free list |
123 | */ |
124 | static inline void raw3215_free_req(struct raw3215_req *req) |
125 | { |
126 | unsigned long flags; |
127 | |
128 | if (req->type == RAW3215_FREE) |
129 | return; /* don't free a free request */ |
130 | req->type = RAW3215_FREE; |
131 | spin_lock_irqsave(&raw3215_freelist_lock, flags); |
132 | req->next = raw3215_freelist; |
133 | raw3215_freelist = req; |
134 | spin_unlock_irqrestore(lock: &raw3215_freelist_lock, flags); |
135 | } |
136 | |
137 | /* |
138 | * Set up a read request that reads up to 160 byte from the 3215 device. |
139 | * If there is a queued read request it is used, but that shouldn't happen |
140 | * because a 3215 terminal won't accept a new read before the old one is |
141 | * completed. |
142 | */ |
143 | static void raw3215_mk_read_req(struct raw3215_info *raw) |
144 | { |
145 | struct raw3215_req *req; |
146 | struct ccw1 *ccw; |
147 | |
148 | /* there can only be ONE read request at a time */ |
149 | req = raw->queued_read; |
150 | if (req == NULL) { |
151 | /* no queued read request, use new req structure */ |
152 | req = raw3215_alloc_req(); |
153 | req->type = RAW3215_READ; |
154 | req->info = raw; |
155 | raw->queued_read = req; |
156 | } |
157 | |
158 | ccw = req->ccws; |
159 | ccw->cmd_code = 0x0A; /* read inquiry */ |
160 | ccw->flags = 0x20; /* ignore incorrect length */ |
161 | ccw->count = 160; |
162 | ccw->cda = virt_to_dma32(raw->inbuf); |
163 | } |
164 | |
165 | /* |
166 | * Set up a write request with the information from the main structure. |
167 | * A ccw chain is created that writes as much as possible from the output |
168 | * buffer to the 3215 device. If a queued write exists it is replaced by |
169 | * the new, probably lengthened request. |
170 | */ |
171 | static void raw3215_mk_write_req(struct raw3215_info *raw) |
172 | { |
173 | struct raw3215_req *req; |
174 | struct ccw1 *ccw; |
175 | int len, count, ix, lines; |
176 | |
177 | if (raw->count <= raw->written) |
178 | return; |
179 | /* check if there is a queued write request */ |
180 | req = raw->queued_write; |
181 | if (req == NULL) { |
182 | /* no queued write request, use new req structure */ |
183 | req = raw3215_alloc_req(); |
184 | req->type = RAW3215_WRITE; |
185 | req->info = raw; |
186 | raw->queued_write = req; |
187 | } else { |
188 | raw->written -= req->len; |
189 | } |
190 | |
191 | ccw = req->ccws; |
192 | req->start = (raw->head - raw->count + raw->written) & |
193 | (RAW3215_BUFFER_SIZE - 1); |
194 | /* |
195 | * now we have to count newlines. We can at max accept |
196 | * RAW3215_MAX_NEWLINE newlines in a single ssch due to |
197 | * a restriction in VM |
198 | */ |
199 | lines = 0; |
200 | ix = req->start; |
201 | while (lines < RAW3215_MAX_NEWLINE && ix != raw->head) { |
202 | if (raw->buffer[ix] == 0x15) |
203 | lines++; |
204 | ix = (ix + 1) & (RAW3215_BUFFER_SIZE - 1); |
205 | } |
206 | len = ((ix - 1 - req->start) & (RAW3215_BUFFER_SIZE - 1)) + 1; |
207 | if (len > RAW3215_MAX_BYTES) |
208 | len = RAW3215_MAX_BYTES; |
209 | req->len = len; |
210 | raw->written += len; |
211 | |
212 | /* set the indication if we should try to enlarge this request */ |
213 | req->delayable = (ix == raw->head) && (len < RAW3215_MIN_WRITE); |
214 | |
215 | ix = req->start; |
216 | while (len > 0) { |
217 | if (ccw > req->ccws) |
218 | ccw[-1].flags |= 0x40; /* use command chaining */ |
219 | ccw->cmd_code = 0x01; /* write, auto carrier return */ |
220 | ccw->flags = 0x20; /* ignore incorrect length ind. */ |
221 | ccw->cda = virt_to_dma32(raw->buffer + ix); |
222 | count = len; |
223 | if (ix + count > RAW3215_BUFFER_SIZE) |
224 | count = RAW3215_BUFFER_SIZE - ix; |
225 | ccw->count = count; |
226 | len -= count; |
227 | ix = (ix + count) & (RAW3215_BUFFER_SIZE - 1); |
228 | ccw++; |
229 | } |
230 | /* |
231 | * Add a NOP to the channel program. 3215 devices are purely |
232 | * emulated and its much better to avoid the channel end |
233 | * interrupt in this case. |
234 | */ |
235 | if (ccw > req->ccws) |
236 | ccw[-1].flags |= 0x40; /* use command chaining */ |
237 | ccw->cmd_code = 0x03; /* NOP */ |
238 | ccw->flags = 0; |
239 | ccw->cda = 0; |
240 | ccw->count = 1; |
241 | } |
242 | |
243 | /* |
244 | * Start a read or a write request |
245 | */ |
246 | static void raw3215_start_io(struct raw3215_info *raw) |
247 | { |
248 | struct raw3215_req *req; |
249 | int res; |
250 | |
251 | req = raw->queued_read; |
252 | if (req != NULL && |
253 | !(raw->flags & (RAW3215_WORKING | RAW3215_THROTTLED))) { |
254 | /* dequeue request */ |
255 | raw->queued_read = NULL; |
256 | res = ccw_device_start(raw->cdev, req->ccws, |
257 | (unsigned long) req, 0, 0); |
258 | if (res != 0) { |
259 | /* do_IO failed, put request back to queue */ |
260 | raw->queued_read = req; |
261 | } else { |
262 | raw->flags |= RAW3215_WORKING; |
263 | } |
264 | } |
265 | req = raw->queued_write; |
266 | if (req != NULL && |
267 | !(raw->flags & (RAW3215_WORKING | RAW3215_STOPPED))) { |
268 | /* dequeue request */ |
269 | raw->queued_write = NULL; |
270 | res = ccw_device_start(raw->cdev, req->ccws, |
271 | (unsigned long) req, 0, 0); |
272 | if (res != 0) { |
273 | /* do_IO failed, put request back to queue */ |
274 | raw->queued_write = req; |
275 | } else { |
276 | raw->flags |= RAW3215_WORKING; |
277 | } |
278 | } |
279 | } |
280 | |
281 | /* |
282 | * Function to start a delayed output after RAW3215_TIMEOUT seconds |
283 | */ |
284 | static void raw3215_timeout(struct timer_list *t) |
285 | { |
286 | struct raw3215_info *raw = from_timer(raw, t, timer); |
287 | unsigned long flags; |
288 | |
289 | spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags); |
290 | raw->flags &= ~RAW3215_TIMER_RUNS; |
291 | raw3215_mk_write_req(raw); |
292 | raw3215_start_io(raw); |
293 | if ((raw->queued_read || raw->queued_write) && |
294 | !(raw->flags & RAW3215_WORKING) && |
295 | !(raw->flags & RAW3215_TIMER_RUNS)) { |
296 | raw->timer.expires = RAW3215_TIMEOUT + jiffies; |
297 | add_timer(timer: &raw->timer); |
298 | raw->flags |= RAW3215_TIMER_RUNS; |
299 | } |
300 | spin_unlock_irqrestore(lock: get_ccwdev_lock(raw->cdev), flags); |
301 | } |
302 | |
303 | /* |
304 | * Function to conditionally start an IO. A read is started immediately, |
305 | * a write is only started immediately if the flush flag is on or the |
306 | * amount of data is bigger than RAW3215_MIN_WRITE. If a write is not |
307 | * done immediately a timer is started with a delay of RAW3215_TIMEOUT. |
308 | */ |
309 | static inline void raw3215_try_io(struct raw3215_info *raw) |
310 | { |
311 | if (!tty_port_initialized(port: &raw->port)) |
312 | return; |
313 | if (raw->queued_read != NULL) |
314 | raw3215_start_io(raw); |
315 | else if (raw->queued_write != NULL) { |
316 | if ((raw->queued_write->delayable == 0) || |
317 | (raw->flags & RAW3215_FLUSHING)) { |
318 | /* execute write requests bigger than minimum size */ |
319 | raw3215_start_io(raw); |
320 | } |
321 | } |
322 | if ((raw->queued_read || raw->queued_write) && |
323 | !(raw->flags & RAW3215_WORKING) && |
324 | !(raw->flags & RAW3215_TIMER_RUNS)) { |
325 | raw->timer.expires = RAW3215_TIMEOUT + jiffies; |
326 | add_timer(timer: &raw->timer); |
327 | raw->flags |= RAW3215_TIMER_RUNS; |
328 | } |
329 | } |
330 | |
331 | /* |
332 | * Try to start the next IO and wake up processes waiting on the tty. |
333 | */ |
334 | static void raw3215_next_io(struct raw3215_info *raw, struct tty_struct *tty) |
335 | { |
336 | raw3215_mk_write_req(raw); |
337 | raw3215_try_io(raw); |
338 | if (tty && RAW3215_BUFFER_SIZE - raw->count >= RAW3215_MIN_SPACE) |
339 | tty_wakeup(tty); |
340 | } |
341 | |
342 | /* |
343 | * Interrupt routine, called from common io layer |
344 | */ |
345 | static void raw3215_irq(struct ccw_device *cdev, unsigned long intparm, |
346 | struct irb *irb) |
347 | { |
348 | struct raw3215_info *raw; |
349 | struct raw3215_req *req; |
350 | struct tty_struct *tty; |
351 | int cstat, dstat; |
352 | int count; |
353 | |
354 | raw = dev_get_drvdata(dev: &cdev->dev); |
355 | req = (struct raw3215_req *) intparm; |
356 | tty = tty_port_tty_get(port: &raw->port); |
357 | cstat = irb->scsw.cmd.cstat; |
358 | dstat = irb->scsw.cmd.dstat; |
359 | if (cstat != 0) |
360 | raw3215_next_io(raw, tty); |
361 | if (dstat & 0x01) { /* we got a unit exception */ |
362 | dstat &= ~0x01; /* we can ignore it */ |
363 | } |
364 | switch (dstat) { |
365 | case 0x80: |
366 | if (cstat != 0) |
367 | break; |
368 | /* Attention interrupt, someone hit the enter key */ |
369 | raw3215_mk_read_req(raw); |
370 | raw3215_next_io(raw, tty); |
371 | break; |
372 | case 0x08: |
373 | case 0x0C: |
374 | /* Channel end interrupt. */ |
375 | if ((raw = req->info) == NULL) |
376 | goto put_tty; /* That shouldn't happen ... */ |
377 | if (req->type == RAW3215_READ) { |
378 | /* store residual count, then wait for device end */ |
379 | req->residual = irb->scsw.cmd.count; |
380 | } |
381 | if (dstat == 0x08) |
382 | break; |
383 | fallthrough; |
384 | case 0x04: |
385 | /* Device end interrupt. */ |
386 | if ((raw = req->info) == NULL) |
387 | goto put_tty; /* That shouldn't happen ... */ |
388 | if (req->type == RAW3215_READ && tty != NULL) { |
389 | unsigned int cchar; |
390 | |
391 | count = 160 - req->residual; |
392 | EBCASC(raw->inbuf, count); |
393 | cchar = ctrlchar_handle(buf: raw->inbuf, len: count, tty); |
394 | switch (cchar & CTRLCHAR_MASK) { |
395 | case CTRLCHAR_SYSRQ: |
396 | break; |
397 | |
398 | case CTRLCHAR_CTRL: |
399 | tty_insert_flip_char(port: &raw->port, ch: cchar, |
400 | TTY_NORMAL); |
401 | tty_flip_buffer_push(port: &raw->port); |
402 | break; |
403 | |
404 | case CTRLCHAR_NONE: |
405 | if (count < 2 || |
406 | (strncmp(raw->inbuf+count-2, "\252n" , 2) && |
407 | strncmp(raw->inbuf+count-2, "^n" , 2)) ) { |
408 | /* add the auto \n */ |
409 | raw->inbuf[count] = '\n'; |
410 | count++; |
411 | } else |
412 | count -= 2; |
413 | tty_insert_flip_string(port: &raw->port, chars: raw->inbuf, |
414 | size: count); |
415 | tty_flip_buffer_push(port: &raw->port); |
416 | break; |
417 | } |
418 | } else if (req->type == RAW3215_WRITE) { |
419 | raw->count -= req->len; |
420 | raw->written -= req->len; |
421 | } |
422 | raw->flags &= ~RAW3215_WORKING; |
423 | raw3215_free_req(req); |
424 | /* check for empty wait */ |
425 | if (waitqueue_active(wq_head: &raw->empty_wait) && |
426 | raw->queued_write == NULL && |
427 | raw->queued_read == NULL) { |
428 | wake_up_interruptible(&raw->empty_wait); |
429 | } |
430 | raw3215_next_io(raw, tty); |
431 | break; |
432 | default: |
433 | /* Strange interrupt, I'll do my best to clean up */ |
434 | if (req != NULL && req->type != RAW3215_FREE) { |
435 | if (req->type == RAW3215_WRITE) { |
436 | raw->count -= req->len; |
437 | raw->written -= req->len; |
438 | } |
439 | raw->flags &= ~RAW3215_WORKING; |
440 | raw3215_free_req(req); |
441 | } |
442 | raw3215_next_io(raw, tty); |
443 | } |
444 | put_tty: |
445 | tty_kref_put(tty); |
446 | } |
447 | |
448 | /* |
449 | * Need to drop data to avoid blocking. Drop as much data as possible. |
450 | * This is unqueued part in the buffer and the queued part in the request. |
451 | * Also adjust the head position to append new data and set count |
452 | * accordingly. |
453 | * |
454 | * Return number of bytes available in buffer. |
455 | */ |
456 | static unsigned int raw3215_drop(struct raw3215_info *raw) |
457 | { |
458 | struct raw3215_req *req; |
459 | |
460 | req = raw->queued_write; |
461 | if (req) { |
462 | /* Drop queued data and delete request */ |
463 | raw->written -= req->len; |
464 | raw3215_free_req(req); |
465 | raw->queued_write = NULL; |
466 | } |
467 | raw->head = (raw->head - raw->count + raw->written) & |
468 | (RAW3215_BUFFER_SIZE - 1); |
469 | raw->count = raw->written; |
470 | |
471 | return RAW3215_BUFFER_SIZE - raw->count; |
472 | } |
473 | |
474 | /* |
475 | * Wait until length bytes are available int the output buffer. |
476 | * If drop mode is active and wait condition holds true, start dropping |
477 | * data. |
478 | * Has to be called with the s390irq lock held. Can be called |
479 | * disabled. |
480 | */ |
481 | static unsigned int raw3215_make_room(struct raw3215_info *raw, |
482 | unsigned int length, bool drop) |
483 | { |
484 | while (RAW3215_BUFFER_SIZE - raw->count < length) { |
485 | if (drop) |
486 | return raw3215_drop(raw); |
487 | |
488 | /* there might be a request pending */ |
489 | raw->flags |= RAW3215_FLUSHING; |
490 | raw3215_mk_write_req(raw); |
491 | raw3215_try_io(raw); |
492 | raw->flags &= ~RAW3215_FLUSHING; |
493 | #ifdef CONFIG_TN3215_CONSOLE |
494 | ccw_device_wait_idle(raw->cdev); |
495 | #endif |
496 | /* Enough room freed up ? */ |
497 | if (RAW3215_BUFFER_SIZE - raw->count >= length) |
498 | break; |
499 | /* there might be another cpu waiting for the lock */ |
500 | spin_unlock(lock: get_ccwdev_lock(raw->cdev)); |
501 | udelay(100); |
502 | spin_lock(lock: get_ccwdev_lock(raw->cdev)); |
503 | } |
504 | return length; |
505 | } |
506 | |
507 | #define RAW3215_COUNT 1 |
508 | #define RAW3215_STORE 2 |
509 | |
510 | /* |
511 | * Add text to console buffer. Find tabs in input and calculate size |
512 | * including tab replacement. |
513 | * This function operates in 2 different modes, depending on parameter |
514 | * opmode: |
515 | * RAW3215_COUNT: Get the size needed for the input string with |
516 | * proper tab replacement calculation. |
517 | * Return value is the number of bytes required to store the |
518 | * input. However no data is actually stored. |
519 | * The parameter todrop is not used. |
520 | * RAW3215_STORE: Add data to the console buffer. The parameter todrop is |
521 | * valid and contains the number of bytes to be dropped from head of |
522 | * string without blocking. |
523 | * Return value is the number of bytes copied. |
524 | */ |
525 | static unsigned int raw3215_addtext(const u8 *str, size_t length, |
526 | struct raw3215_info *raw, int opmode, |
527 | unsigned int todrop) |
528 | { |
529 | unsigned int i, blanks, expanded_size = 0; |
530 | unsigned int column = raw->line_pos; |
531 | size_t c; |
532 | u8 ch; |
533 | |
534 | if (opmode == RAW3215_COUNT) |
535 | todrop = 0; |
536 | |
537 | for (c = 0; c < length; ++c) { |
538 | blanks = 1; |
539 | ch = str[c]; |
540 | |
541 | switch (ch) { |
542 | case '\n': |
543 | expanded_size++; |
544 | column = 0; |
545 | break; |
546 | case '\t': |
547 | blanks = TAB_STOP_SIZE - (column % TAB_STOP_SIZE); |
548 | column += blanks; |
549 | expanded_size += blanks; |
550 | ch = ' '; |
551 | break; |
552 | default: |
553 | expanded_size++; |
554 | column++; |
555 | break; |
556 | } |
557 | |
558 | if (opmode == RAW3215_COUNT) |
559 | continue; |
560 | if (todrop && expanded_size < todrop) /* Drop head data */ |
561 | continue; |
562 | for (i = 0; i < blanks; i++) { |
563 | raw->buffer[raw->head] = _ascebc[ch]; |
564 | raw->head = (raw->head + 1) & (RAW3215_BUFFER_SIZE - 1); |
565 | raw->count++; |
566 | } |
567 | raw->line_pos = column; |
568 | } |
569 | return expanded_size - todrop; |
570 | } |
571 | |
572 | /* |
573 | * String write routine for 3215 devices |
574 | */ |
575 | static void raw3215_write(struct raw3215_info *raw, const u8 *str, |
576 | size_t length) |
577 | { |
578 | unsigned int count, avail; |
579 | unsigned long flags; |
580 | |
581 | spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags); |
582 | |
583 | count = raw3215_addtext(str, length, raw, RAW3215_COUNT, todrop: 0); |
584 | |
585 | avail = raw3215_make_room(raw, length: count, drop: con3215_drop); |
586 | if (avail) { |
587 | raw3215_addtext(str, length, raw, RAW3215_STORE, |
588 | todrop: count - avail); |
589 | } |
590 | if (!(raw->flags & RAW3215_WORKING)) { |
591 | raw3215_mk_write_req(raw); |
592 | /* start or queue request */ |
593 | raw3215_try_io(raw); |
594 | } |
595 | spin_unlock_irqrestore(lock: get_ccwdev_lock(raw->cdev), flags); |
596 | } |
597 | |
598 | /* |
599 | * Put character routine for 3215 devices |
600 | */ |
601 | static void raw3215_putchar(struct raw3215_info *raw, u8 ch) |
602 | { |
603 | raw3215_write(raw, str: &ch, length: 1); |
604 | } |
605 | |
606 | /* |
607 | * Flush routine, it simply sets the flush flag and tries to start |
608 | * pending IO. |
609 | */ |
610 | static void raw3215_flush_buffer(struct raw3215_info *raw) |
611 | { |
612 | unsigned long flags; |
613 | |
614 | spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags); |
615 | if (raw->count > 0) { |
616 | raw->flags |= RAW3215_FLUSHING; |
617 | raw3215_try_io(raw); |
618 | raw->flags &= ~RAW3215_FLUSHING; |
619 | } |
620 | spin_unlock_irqrestore(lock: get_ccwdev_lock(raw->cdev), flags); |
621 | } |
622 | |
623 | /* |
624 | * Fire up a 3215 device. |
625 | */ |
626 | static int raw3215_startup(struct raw3215_info *raw) |
627 | { |
628 | unsigned long flags; |
629 | |
630 | if (tty_port_initialized(port: &raw->port)) |
631 | return 0; |
632 | raw->line_pos = 0; |
633 | tty_port_set_initialized(port: &raw->port, val: true); |
634 | spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags); |
635 | raw3215_try_io(raw); |
636 | spin_unlock_irqrestore(lock: get_ccwdev_lock(raw->cdev), flags); |
637 | |
638 | return 0; |
639 | } |
640 | |
641 | /* |
642 | * Shutdown a 3215 device. |
643 | */ |
644 | static void raw3215_shutdown(struct raw3215_info *raw) |
645 | { |
646 | DECLARE_WAITQUEUE(wait, current); |
647 | unsigned long flags; |
648 | |
649 | if (!tty_port_initialized(port: &raw->port) || (raw->flags & RAW3215_FIXED)) |
650 | return; |
651 | /* Wait for outstanding requests, then free irq */ |
652 | spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags); |
653 | if ((raw->flags & RAW3215_WORKING) || |
654 | raw->queued_write != NULL || |
655 | raw->queued_read != NULL) { |
656 | add_wait_queue(wq_head: &raw->empty_wait, wq_entry: &wait); |
657 | set_current_state(TASK_INTERRUPTIBLE); |
658 | spin_unlock_irqrestore(lock: get_ccwdev_lock(raw->cdev), flags); |
659 | schedule(); |
660 | spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags); |
661 | remove_wait_queue(wq_head: &raw->empty_wait, wq_entry: &wait); |
662 | set_current_state(TASK_RUNNING); |
663 | tty_port_set_initialized(port: &raw->port, val: true); |
664 | } |
665 | spin_unlock_irqrestore(lock: get_ccwdev_lock(raw->cdev), flags); |
666 | } |
667 | |
668 | static struct raw3215_info *raw3215_alloc_info(void) |
669 | { |
670 | struct raw3215_info *info; |
671 | |
672 | info = kzalloc(size: sizeof(struct raw3215_info), GFP_KERNEL | GFP_DMA); |
673 | if (!info) |
674 | return NULL; |
675 | |
676 | info->buffer = kzalloc(RAW3215_BUFFER_SIZE, GFP_KERNEL | GFP_DMA); |
677 | info->inbuf = kzalloc(RAW3215_INBUF_SIZE, GFP_KERNEL | GFP_DMA); |
678 | if (!info->buffer || !info->inbuf) { |
679 | kfree(objp: info->inbuf); |
680 | kfree(objp: info->buffer); |
681 | kfree(objp: info); |
682 | return NULL; |
683 | } |
684 | |
685 | timer_setup(&info->timer, raw3215_timeout, 0); |
686 | init_waitqueue_head(&info->empty_wait); |
687 | tty_port_init(port: &info->port); |
688 | |
689 | return info; |
690 | } |
691 | |
692 | static void raw3215_free_info(struct raw3215_info *raw) |
693 | { |
694 | kfree(objp: raw->inbuf); |
695 | kfree(objp: raw->buffer); |
696 | tty_port_destroy(port: &raw->port); |
697 | kfree(objp: raw); |
698 | } |
699 | |
700 | static int raw3215_probe(struct ccw_device *cdev) |
701 | { |
702 | struct raw3215_info *raw; |
703 | int line; |
704 | |
705 | /* Console is special. */ |
706 | if (raw3215[0] && (raw3215[0] == dev_get_drvdata(dev: &cdev->dev))) |
707 | return 0; |
708 | |
709 | raw = raw3215_alloc_info(); |
710 | if (raw == NULL) |
711 | return -ENOMEM; |
712 | |
713 | raw->cdev = cdev; |
714 | dev_set_drvdata(dev: &cdev->dev, data: raw); |
715 | cdev->handler = raw3215_irq; |
716 | |
717 | spin_lock(lock: &raw3215_device_lock); |
718 | for (line = 0; line < NR_3215; line++) { |
719 | if (!raw3215[line]) { |
720 | raw3215[line] = raw; |
721 | break; |
722 | } |
723 | } |
724 | spin_unlock(lock: &raw3215_device_lock); |
725 | if (line == NR_3215) { |
726 | raw3215_free_info(raw); |
727 | return -ENODEV; |
728 | } |
729 | |
730 | return 0; |
731 | } |
732 | |
733 | static void raw3215_remove(struct ccw_device *cdev) |
734 | { |
735 | struct raw3215_info *raw; |
736 | unsigned int line; |
737 | |
738 | ccw_device_set_offline(cdev); |
739 | raw = dev_get_drvdata(dev: &cdev->dev); |
740 | if (raw) { |
741 | spin_lock(lock: &raw3215_device_lock); |
742 | for (line = 0; line < NR_3215; line++) |
743 | if (raw3215[line] == raw) |
744 | break; |
745 | raw3215[line] = NULL; |
746 | spin_unlock(lock: &raw3215_device_lock); |
747 | dev_set_drvdata(dev: &cdev->dev, NULL); |
748 | raw3215_free_info(raw); |
749 | } |
750 | } |
751 | |
752 | static int raw3215_set_online(struct ccw_device *cdev) |
753 | { |
754 | struct raw3215_info *raw; |
755 | |
756 | raw = dev_get_drvdata(dev: &cdev->dev); |
757 | if (!raw) |
758 | return -ENODEV; |
759 | |
760 | return raw3215_startup(raw); |
761 | } |
762 | |
763 | static int raw3215_set_offline(struct ccw_device *cdev) |
764 | { |
765 | struct raw3215_info *raw; |
766 | |
767 | raw = dev_get_drvdata(dev: &cdev->dev); |
768 | if (!raw) |
769 | return -ENODEV; |
770 | |
771 | raw3215_shutdown(raw); |
772 | |
773 | return 0; |
774 | } |
775 | |
776 | static struct ccw_device_id raw3215_id[] = { |
777 | { CCW_DEVICE(0x3215, 0) }, |
778 | { /* end of list */ }, |
779 | }; |
780 | |
781 | static ssize_t con_drop_store(struct device_driver *dev, const char *buf, size_t count) |
782 | { |
783 | bool drop; |
784 | int rc; |
785 | |
786 | rc = kstrtobool(s: buf, res: &drop); |
787 | if (!rc) |
788 | con3215_drop = drop; |
789 | return rc ?: count; |
790 | } |
791 | |
792 | static ssize_t con_drop_show(struct device_driver *dev, char *buf) |
793 | { |
794 | return sysfs_emit(buf, fmt: "%d\n" , con3215_drop ? 1 : 0); |
795 | } |
796 | |
797 | static DRIVER_ATTR_RW(con_drop); |
798 | |
799 | static struct attribute *con3215_drv_attrs[] = { |
800 | &driver_attr_con_drop.attr, |
801 | NULL, |
802 | }; |
803 | |
804 | static struct attribute_group con3215_drv_attr_group = { |
805 | .attrs = con3215_drv_attrs, |
806 | NULL, |
807 | }; |
808 | |
809 | static const struct attribute_group *con3215_drv_attr_groups[] = { |
810 | &con3215_drv_attr_group, |
811 | NULL, |
812 | }; |
813 | |
814 | static struct ccw_driver raw3215_ccw_driver = { |
815 | .driver = { |
816 | .name = "3215" , |
817 | .groups = con3215_drv_attr_groups, |
818 | .owner = THIS_MODULE, |
819 | }, |
820 | .ids = raw3215_id, |
821 | .probe = &raw3215_probe, |
822 | .remove = &raw3215_remove, |
823 | .set_online = &raw3215_set_online, |
824 | .set_offline = &raw3215_set_offline, |
825 | .int_class = IRQIO_C15, |
826 | }; |
827 | |
828 | static void handle_write(struct raw3215_info *raw, const u8 *str, size_t count) |
829 | { |
830 | while (count > 0) { |
831 | size_t i = min_t(size_t, count, RAW3215_BUFFER_SIZE - 1); |
832 | raw3215_write(raw, str, length: i); |
833 | count -= i; |
834 | str += i; |
835 | } |
836 | } |
837 | |
838 | #ifdef CONFIG_TN3215_CONSOLE |
839 | /* |
840 | * Write a string to the 3215 console |
841 | */ |
842 | static void con3215_write(struct console *co, const char *str, unsigned int count) |
843 | { |
844 | handle_write(raw3215[0], str, count); |
845 | } |
846 | |
847 | static struct tty_driver *con3215_device(struct console *c, int *index) |
848 | { |
849 | *index = c->index; |
850 | return tty3215_driver; |
851 | } |
852 | |
853 | /* |
854 | * The below function is called as a panic/reboot notifier before the |
855 | * system enters a disabled, endless loop. |
856 | * |
857 | * Notice we must use the spin_trylock() alternative, to prevent lockups |
858 | * in atomic context (panic routine runs with secondary CPUs, local IRQs |
859 | * and preemption disabled). |
860 | */ |
861 | static int con3215_notify(struct notifier_block *self, |
862 | unsigned long event, void *data) |
863 | { |
864 | struct raw3215_info *raw; |
865 | unsigned long flags; |
866 | |
867 | raw = raw3215[0]; /* console 3215 is the first one */ |
868 | if (!spin_trylock_irqsave(get_ccwdev_lock(raw->cdev), flags)) |
869 | return NOTIFY_DONE; |
870 | raw3215_make_room(raw, RAW3215_BUFFER_SIZE, false); |
871 | spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags); |
872 | |
873 | return NOTIFY_DONE; |
874 | } |
875 | |
876 | static struct notifier_block on_panic_nb = { |
877 | .notifier_call = con3215_notify, |
878 | .priority = INT_MIN + 1, /* run the callback late */ |
879 | }; |
880 | |
881 | static struct notifier_block on_reboot_nb = { |
882 | .notifier_call = con3215_notify, |
883 | .priority = INT_MIN + 1, /* run the callback late */ |
884 | }; |
885 | |
886 | /* |
887 | * The console structure for the 3215 console |
888 | */ |
889 | static struct console con3215 = { |
890 | .name = "ttyS" , |
891 | .write = con3215_write, |
892 | .device = con3215_device, |
893 | .flags = CON_PRINTBUFFER, |
894 | }; |
895 | |
896 | /* |
897 | * 3215 console initialization code called from console_init(). |
898 | */ |
899 | static int __init con3215_init(void) |
900 | { |
901 | struct ccw_device *cdev; |
902 | struct raw3215_info *raw; |
903 | struct raw3215_req *req; |
904 | int i; |
905 | |
906 | /* Check if 3215 is to be the console */ |
907 | if (!CONSOLE_IS_3215) |
908 | return -ENODEV; |
909 | |
910 | /* Set the console mode for VM */ |
911 | if (MACHINE_IS_VM) { |
912 | cpcmd("TERM CONMODE 3215" , NULL, 0, NULL); |
913 | cpcmd("TERM AUTOCR OFF" , NULL, 0, NULL); |
914 | } |
915 | |
916 | /* allocate 3215 request structures */ |
917 | raw3215_freelist = NULL; |
918 | for (i = 0; i < NR_3215_REQ; i++) { |
919 | req = kzalloc(sizeof(struct raw3215_req), GFP_KERNEL | GFP_DMA); |
920 | if (!req) |
921 | return -ENOMEM; |
922 | req->next = raw3215_freelist; |
923 | raw3215_freelist = req; |
924 | } |
925 | |
926 | cdev = ccw_device_create_console(&raw3215_ccw_driver); |
927 | if (IS_ERR(cdev)) |
928 | return -ENODEV; |
929 | |
930 | raw3215[0] = raw = raw3215_alloc_info(); |
931 | raw->cdev = cdev; |
932 | dev_set_drvdata(&cdev->dev, raw); |
933 | cdev->handler = raw3215_irq; |
934 | |
935 | raw->flags |= RAW3215_FIXED; |
936 | if (ccw_device_enable_console(cdev)) { |
937 | ccw_device_destroy_console(cdev); |
938 | raw3215_free_info(raw); |
939 | raw3215[0] = NULL; |
940 | return -ENODEV; |
941 | } |
942 | |
943 | /* Request the console irq */ |
944 | if (raw3215_startup(raw) != 0) { |
945 | raw3215_free_info(raw); |
946 | raw3215[0] = NULL; |
947 | return -ENODEV; |
948 | } |
949 | atomic_notifier_chain_register(&panic_notifier_list, &on_panic_nb); |
950 | register_reboot_notifier(&on_reboot_nb); |
951 | register_console(&con3215); |
952 | return 0; |
953 | } |
954 | console_initcall(con3215_init); |
955 | #endif |
956 | |
957 | static int tty3215_install(struct tty_driver *driver, struct tty_struct *tty) |
958 | { |
959 | struct raw3215_info *raw; |
960 | |
961 | raw = raw3215[tty->index]; |
962 | if (raw == NULL) |
963 | return -ENODEV; |
964 | |
965 | tty->driver_data = raw; |
966 | |
967 | return tty_port_install(port: &raw->port, driver, tty); |
968 | } |
969 | |
970 | /* |
971 | * tty3215_open |
972 | * |
973 | * This routine is called whenever a 3215 tty is opened. |
974 | */ |
975 | static int tty3215_open(struct tty_struct *tty, struct file * filp) |
976 | { |
977 | struct raw3215_info *raw = tty->driver_data; |
978 | |
979 | tty_port_tty_set(port: &raw->port, tty); |
980 | |
981 | /* |
982 | * Start up 3215 device |
983 | */ |
984 | return raw3215_startup(raw); |
985 | } |
986 | |
987 | /* |
988 | * tty3215_close() |
989 | * |
990 | * This routine is called when the 3215 tty is closed. We wait |
991 | * for the remaining request to be completed. Then we clean up. |
992 | */ |
993 | static void tty3215_close(struct tty_struct *tty, struct file * filp) |
994 | { |
995 | struct raw3215_info *raw = tty->driver_data; |
996 | |
997 | if (raw == NULL || tty->count > 1) |
998 | return; |
999 | tty->closing = 1; |
1000 | /* Shutdown the terminal */ |
1001 | raw3215_shutdown(raw); |
1002 | tty->closing = 0; |
1003 | tty_port_tty_set(port: &raw->port, NULL); |
1004 | } |
1005 | |
1006 | /* |
1007 | * Returns the amount of free space in the output buffer. |
1008 | */ |
1009 | static unsigned int tty3215_write_room(struct tty_struct *tty) |
1010 | { |
1011 | struct raw3215_info *raw = tty->driver_data; |
1012 | |
1013 | /* Subtract TAB_STOP_SIZE to allow for a tab, 8 <<< 64K */ |
1014 | if ((RAW3215_BUFFER_SIZE - raw->count - TAB_STOP_SIZE) >= 0) |
1015 | return RAW3215_BUFFER_SIZE - raw->count - TAB_STOP_SIZE; |
1016 | else |
1017 | return 0; |
1018 | } |
1019 | |
1020 | /* |
1021 | * String write routine for 3215 ttys |
1022 | */ |
1023 | static ssize_t tty3215_write(struct tty_struct *tty, const u8 *buf, |
1024 | size_t count) |
1025 | { |
1026 | handle_write(raw: tty->driver_data, str: buf, count); |
1027 | return count; |
1028 | } |
1029 | |
1030 | /* |
1031 | * Put character routine for 3215 ttys |
1032 | */ |
1033 | static int tty3215_put_char(struct tty_struct *tty, u8 ch) |
1034 | { |
1035 | struct raw3215_info *raw = tty->driver_data; |
1036 | |
1037 | raw3215_putchar(raw, ch); |
1038 | |
1039 | return 1; |
1040 | } |
1041 | |
1042 | static void tty3215_flush_chars(struct tty_struct *tty) |
1043 | { |
1044 | } |
1045 | |
1046 | /* |
1047 | * Returns the number of characters in the output buffer |
1048 | */ |
1049 | static unsigned int tty3215_chars_in_buffer(struct tty_struct *tty) |
1050 | { |
1051 | struct raw3215_info *raw = tty->driver_data; |
1052 | |
1053 | return raw->count; |
1054 | } |
1055 | |
1056 | static void tty3215_flush_buffer(struct tty_struct *tty) |
1057 | { |
1058 | struct raw3215_info *raw = tty->driver_data; |
1059 | |
1060 | raw3215_flush_buffer(raw); |
1061 | tty_wakeup(tty); |
1062 | } |
1063 | |
1064 | /* |
1065 | * Disable reading from a 3215 tty |
1066 | */ |
1067 | static void tty3215_throttle(struct tty_struct *tty) |
1068 | { |
1069 | struct raw3215_info *raw = tty->driver_data; |
1070 | |
1071 | raw->flags |= RAW3215_THROTTLED; |
1072 | } |
1073 | |
1074 | /* |
1075 | * Enable reading from a 3215 tty |
1076 | */ |
1077 | static void tty3215_unthrottle(struct tty_struct *tty) |
1078 | { |
1079 | struct raw3215_info *raw = tty->driver_data; |
1080 | unsigned long flags; |
1081 | |
1082 | if (raw->flags & RAW3215_THROTTLED) { |
1083 | spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags); |
1084 | raw->flags &= ~RAW3215_THROTTLED; |
1085 | raw3215_try_io(raw); |
1086 | spin_unlock_irqrestore(lock: get_ccwdev_lock(raw->cdev), flags); |
1087 | } |
1088 | } |
1089 | |
1090 | /* |
1091 | * Disable writing to a 3215 tty |
1092 | */ |
1093 | static void tty3215_stop(struct tty_struct *tty) |
1094 | { |
1095 | struct raw3215_info *raw = tty->driver_data; |
1096 | |
1097 | raw->flags |= RAW3215_STOPPED; |
1098 | } |
1099 | |
1100 | /* |
1101 | * Enable writing to a 3215 tty |
1102 | */ |
1103 | static void tty3215_start(struct tty_struct *tty) |
1104 | { |
1105 | struct raw3215_info *raw = tty->driver_data; |
1106 | unsigned long flags; |
1107 | |
1108 | if (raw->flags & RAW3215_STOPPED) { |
1109 | spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags); |
1110 | raw->flags &= ~RAW3215_STOPPED; |
1111 | raw3215_try_io(raw); |
1112 | spin_unlock_irqrestore(lock: get_ccwdev_lock(raw->cdev), flags); |
1113 | } |
1114 | } |
1115 | |
1116 | static const struct tty_operations tty3215_ops = { |
1117 | .install = tty3215_install, |
1118 | .open = tty3215_open, |
1119 | .close = tty3215_close, |
1120 | .write = tty3215_write, |
1121 | .put_char = tty3215_put_char, |
1122 | .flush_chars = tty3215_flush_chars, |
1123 | .write_room = tty3215_write_room, |
1124 | .chars_in_buffer = tty3215_chars_in_buffer, |
1125 | .flush_buffer = tty3215_flush_buffer, |
1126 | .throttle = tty3215_throttle, |
1127 | .unthrottle = tty3215_unthrottle, |
1128 | .stop = tty3215_stop, |
1129 | .start = tty3215_start, |
1130 | }; |
1131 | |
1132 | static int __init con3215_setup_drop(char *str) |
1133 | { |
1134 | bool drop; |
1135 | int rc; |
1136 | |
1137 | rc = kstrtobool(s: str, res: &drop); |
1138 | if (!rc) |
1139 | con3215_drop = drop; |
1140 | return rc; |
1141 | } |
1142 | early_param("con3215_drop" , con3215_setup_drop); |
1143 | |
1144 | /* |
1145 | * 3215 tty registration code called from tty_init(). |
1146 | * Most kernel services (incl. kmalloc) are available at this poimt. |
1147 | */ |
1148 | static int __init tty3215_init(void) |
1149 | { |
1150 | struct tty_driver *driver; |
1151 | int ret; |
1152 | |
1153 | if (!CONSOLE_IS_3215) |
1154 | return 0; |
1155 | |
1156 | driver = tty_alloc_driver(NR_3215, TTY_DRIVER_REAL_RAW); |
1157 | if (IS_ERR(ptr: driver)) |
1158 | return PTR_ERR(ptr: driver); |
1159 | |
1160 | ret = ccw_driver_register(&raw3215_ccw_driver); |
1161 | if (ret) { |
1162 | tty_driver_kref_put(driver); |
1163 | return ret; |
1164 | } |
1165 | /* |
1166 | * Initialize the tty_driver structure |
1167 | * Entries in tty3215_driver that are NOT initialized: |
1168 | * proc_entry, set_termios, flush_buffer, set_ldisc, write_proc |
1169 | */ |
1170 | |
1171 | driver->driver_name = "tty3215" ; |
1172 | driver->name = "ttyS" ; |
1173 | driver->major = TTY_MAJOR; |
1174 | driver->minor_start = 64; |
1175 | driver->type = TTY_DRIVER_TYPE_SYSTEM; |
1176 | driver->subtype = SYSTEM_TYPE_TTY; |
1177 | driver->init_termios = tty_std_termios; |
1178 | driver->init_termios.c_iflag = IGNBRK | IGNPAR; |
1179 | driver->init_termios.c_oflag = ONLCR; |
1180 | driver->init_termios.c_lflag = ISIG; |
1181 | tty_set_operations(driver, op: &tty3215_ops); |
1182 | ret = tty_register_driver(driver); |
1183 | if (ret) { |
1184 | tty_driver_kref_put(driver); |
1185 | return ret; |
1186 | } |
1187 | tty3215_driver = driver; |
1188 | return 0; |
1189 | } |
1190 | device_initcall(tty3215_init); |
1191 | |