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 | char *buffer; /* pointer to output buffer */ |
83 | char *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 | char ubuffer[80]; /* copy_from_user buffer */ |
93 | }; |
94 | |
95 | /* array of 3215 devices structures */ |
96 | static struct raw3215_info *raw3215[NR_3215]; |
97 | /* spinlock to protect the raw3215 array */ |
98 | static DEFINE_SPINLOCK(raw3215_device_lock); |
99 | /* list of free request structures */ |
100 | static struct raw3215_req *raw3215_freelist; |
101 | /* spinlock to protect free list */ |
102 | static DEFINE_SPINLOCK(raw3215_freelist_lock); |
103 | |
104 | static struct tty_driver *tty3215_driver; |
105 | static bool con3215_drop = true; |
106 | |
107 | /* |
108 | * Get a request structure from the free list |
109 | */ |
110 | static inline struct raw3215_req *raw3215_alloc_req(void) |
111 | { |
112 | struct raw3215_req *req; |
113 | unsigned long flags; |
114 | |
115 | spin_lock_irqsave(&raw3215_freelist_lock, flags); |
116 | req = raw3215_freelist; |
117 | raw3215_freelist = req->next; |
118 | spin_unlock_irqrestore(lock: &raw3215_freelist_lock, flags); |
119 | return req; |
120 | } |
121 | |
122 | /* |
123 | * Put a request structure back to the free list |
124 | */ |
125 | static inline void raw3215_free_req(struct raw3215_req *req) |
126 | { |
127 | unsigned long flags; |
128 | |
129 | if (req->type == RAW3215_FREE) |
130 | return; /* don't free a free request */ |
131 | req->type = RAW3215_FREE; |
132 | spin_lock_irqsave(&raw3215_freelist_lock, flags); |
133 | req->next = raw3215_freelist; |
134 | raw3215_freelist = req; |
135 | spin_unlock_irqrestore(lock: &raw3215_freelist_lock, flags); |
136 | } |
137 | |
138 | /* |
139 | * Set up a read request that reads up to 160 byte from the 3215 device. |
140 | * If there is a queued read request it is used, but that shouldn't happen |
141 | * because a 3215 terminal won't accept a new read before the old one is |
142 | * completed. |
143 | */ |
144 | static void raw3215_mk_read_req(struct raw3215_info *raw) |
145 | { |
146 | struct raw3215_req *req; |
147 | struct ccw1 *ccw; |
148 | |
149 | /* there can only be ONE read request at a time */ |
150 | req = raw->queued_read; |
151 | if (req == NULL) { |
152 | /* no queued read request, use new req structure */ |
153 | req = raw3215_alloc_req(); |
154 | req->type = RAW3215_READ; |
155 | req->info = raw; |
156 | raw->queued_read = req; |
157 | } |
158 | |
159 | ccw = req->ccws; |
160 | ccw->cmd_code = 0x0A; /* read inquiry */ |
161 | ccw->flags = 0x20; /* ignore incorrect length */ |
162 | ccw->count = 160; |
163 | ccw->cda = (__u32)__pa(raw->inbuf); |
164 | } |
165 | |
166 | /* |
167 | * Set up a write request with the information from the main structure. |
168 | * A ccw chain is created that writes as much as possible from the output |
169 | * buffer to the 3215 device. If a queued write exists it is replaced by |
170 | * the new, probably lengthened request. |
171 | */ |
172 | static void raw3215_mk_write_req(struct raw3215_info *raw) |
173 | { |
174 | struct raw3215_req *req; |
175 | struct ccw1 *ccw; |
176 | int len, count, ix, lines; |
177 | |
178 | if (raw->count <= raw->written) |
179 | return; |
180 | /* check if there is a queued write request */ |
181 | req = raw->queued_write; |
182 | if (req == NULL) { |
183 | /* no queued write request, use new req structure */ |
184 | req = raw3215_alloc_req(); |
185 | req->type = RAW3215_WRITE; |
186 | req->info = raw; |
187 | raw->queued_write = req; |
188 | } else { |
189 | raw->written -= req->len; |
190 | } |
191 | |
192 | ccw = req->ccws; |
193 | req->start = (raw->head - raw->count + raw->written) & |
194 | (RAW3215_BUFFER_SIZE - 1); |
195 | /* |
196 | * now we have to count newlines. We can at max accept |
197 | * RAW3215_MAX_NEWLINE newlines in a single ssch due to |
198 | * a restriction in VM |
199 | */ |
200 | lines = 0; |
201 | ix = req->start; |
202 | while (lines < RAW3215_MAX_NEWLINE && ix != raw->head) { |
203 | if (raw->buffer[ix] == 0x15) |
204 | lines++; |
205 | ix = (ix + 1) & (RAW3215_BUFFER_SIZE - 1); |
206 | } |
207 | len = ((ix - 1 - req->start) & (RAW3215_BUFFER_SIZE - 1)) + 1; |
208 | if (len > RAW3215_MAX_BYTES) |
209 | len = RAW3215_MAX_BYTES; |
210 | req->len = len; |
211 | raw->written += len; |
212 | |
213 | /* set the indication if we should try to enlarge this request */ |
214 | req->delayable = (ix == raw->head) && (len < RAW3215_MIN_WRITE); |
215 | |
216 | ix = req->start; |
217 | while (len > 0) { |
218 | if (ccw > req->ccws) |
219 | ccw[-1].flags |= 0x40; /* use command chaining */ |
220 | ccw->cmd_code = 0x01; /* write, auto carrier return */ |
221 | ccw->flags = 0x20; /* ignore incorrect length ind. */ |
222 | ccw->cda = (__u32)__pa(raw->buffer + ix); |
223 | count = len; |
224 | if (ix + count > RAW3215_BUFFER_SIZE) |
225 | count = RAW3215_BUFFER_SIZE - ix; |
226 | ccw->count = count; |
227 | len -= count; |
228 | ix = (ix + count) & (RAW3215_BUFFER_SIZE - 1); |
229 | ccw++; |
230 | } |
231 | /* |
232 | * Add a NOP to the channel program. 3215 devices are purely |
233 | * emulated and its much better to avoid the channel end |
234 | * interrupt in this case. |
235 | */ |
236 | if (ccw > req->ccws) |
237 | ccw[-1].flags |= 0x40; /* use command chaining */ |
238 | ccw->cmd_code = 0x03; /* NOP */ |
239 | ccw->flags = 0; |
240 | ccw->cda = 0; |
241 | ccw->count = 1; |
242 | } |
243 | |
244 | /* |
245 | * Start a read or a write request |
246 | */ |
247 | static void raw3215_start_io(struct raw3215_info *raw) |
248 | { |
249 | struct raw3215_req *req; |
250 | int res; |
251 | |
252 | req = raw->queued_read; |
253 | if (req != NULL && |
254 | !(raw->flags & (RAW3215_WORKING | RAW3215_THROTTLED))) { |
255 | /* dequeue request */ |
256 | raw->queued_read = NULL; |
257 | res = ccw_device_start(raw->cdev, req->ccws, |
258 | (unsigned long) req, 0, 0); |
259 | if (res != 0) { |
260 | /* do_IO failed, put request back to queue */ |
261 | raw->queued_read = req; |
262 | } else { |
263 | raw->flags |= RAW3215_WORKING; |
264 | } |
265 | } |
266 | req = raw->queued_write; |
267 | if (req != NULL && |
268 | !(raw->flags & (RAW3215_WORKING | RAW3215_STOPPED))) { |
269 | /* dequeue request */ |
270 | raw->queued_write = NULL; |
271 | res = ccw_device_start(raw->cdev, req->ccws, |
272 | (unsigned long) req, 0, 0); |
273 | if (res != 0) { |
274 | /* do_IO failed, put request back to queue */ |
275 | raw->queued_write = req; |
276 | } else { |
277 | raw->flags |= RAW3215_WORKING; |
278 | } |
279 | } |
280 | } |
281 | |
282 | /* |
283 | * Function to start a delayed output after RAW3215_TIMEOUT seconds |
284 | */ |
285 | static void raw3215_timeout(struct timer_list *t) |
286 | { |
287 | struct raw3215_info *raw = from_timer(raw, t, timer); |
288 | unsigned long flags; |
289 | |
290 | spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags); |
291 | raw->flags &= ~RAW3215_TIMER_RUNS; |
292 | raw3215_mk_write_req(raw); |
293 | raw3215_start_io(raw); |
294 | if ((raw->queued_read || raw->queued_write) && |
295 | !(raw->flags & RAW3215_WORKING) && |
296 | !(raw->flags & RAW3215_TIMER_RUNS)) { |
297 | raw->timer.expires = RAW3215_TIMEOUT + jiffies; |
298 | add_timer(timer: &raw->timer); |
299 | raw->flags |= RAW3215_TIMER_RUNS; |
300 | } |
301 | spin_unlock_irqrestore(lock: get_ccwdev_lock(raw->cdev), flags); |
302 | } |
303 | |
304 | /* |
305 | * Function to conditionally start an IO. A read is started immediately, |
306 | * a write is only started immediately if the flush flag is on or the |
307 | * amount of data is bigger than RAW3215_MIN_WRITE. If a write is not |
308 | * done immediately a timer is started with a delay of RAW3215_TIMEOUT. |
309 | */ |
310 | static inline void raw3215_try_io(struct raw3215_info *raw) |
311 | { |
312 | if (!tty_port_initialized(port: &raw->port)) |
313 | return; |
314 | if (raw->queued_read != NULL) |
315 | raw3215_start_io(raw); |
316 | else if (raw->queued_write != NULL) { |
317 | if ((raw->queued_write->delayable == 0) || |
318 | (raw->flags & RAW3215_FLUSHING)) { |
319 | /* execute write requests bigger than minimum size */ |
320 | raw3215_start_io(raw); |
321 | } |
322 | } |
323 | if ((raw->queued_read || raw->queued_write) && |
324 | !(raw->flags & RAW3215_WORKING) && |
325 | !(raw->flags & RAW3215_TIMER_RUNS)) { |
326 | raw->timer.expires = RAW3215_TIMEOUT + jiffies; |
327 | add_timer(timer: &raw->timer); |
328 | raw->flags |= RAW3215_TIMER_RUNS; |
329 | } |
330 | } |
331 | |
332 | /* |
333 | * Try to start the next IO and wake up processes waiting on the tty. |
334 | */ |
335 | static void raw3215_next_io(struct raw3215_info *raw, struct tty_struct *tty) |
336 | { |
337 | raw3215_mk_write_req(raw); |
338 | raw3215_try_io(raw); |
339 | if (tty && RAW3215_BUFFER_SIZE - raw->count >= RAW3215_MIN_SPACE) |
340 | tty_wakeup(tty); |
341 | } |
342 | |
343 | /* |
344 | * Interrupt routine, called from common io layer |
345 | */ |
346 | static void raw3215_irq(struct ccw_device *cdev, unsigned long intparm, |
347 | struct irb *irb) |
348 | { |
349 | struct raw3215_info *raw; |
350 | struct raw3215_req *req; |
351 | struct tty_struct *tty; |
352 | int cstat, dstat; |
353 | int count; |
354 | |
355 | raw = dev_get_drvdata(dev: &cdev->dev); |
356 | req = (struct raw3215_req *) intparm; |
357 | tty = tty_port_tty_get(port: &raw->port); |
358 | cstat = irb->scsw.cmd.cstat; |
359 | dstat = irb->scsw.cmd.dstat; |
360 | if (cstat != 0) |
361 | raw3215_next_io(raw, tty); |
362 | if (dstat & 0x01) { /* we got a unit exception */ |
363 | dstat &= ~0x01; /* we can ignore it */ |
364 | } |
365 | switch (dstat) { |
366 | case 0x80: |
367 | if (cstat != 0) |
368 | break; |
369 | /* Attention interrupt, someone hit the enter key */ |
370 | raw3215_mk_read_req(raw); |
371 | raw3215_next_io(raw, tty); |
372 | break; |
373 | case 0x08: |
374 | case 0x0C: |
375 | /* Channel end interrupt. */ |
376 | if ((raw = req->info) == NULL) |
377 | goto put_tty; /* That shouldn't happen ... */ |
378 | if (req->type == RAW3215_READ) { |
379 | /* store residual count, then wait for device end */ |
380 | req->residual = irb->scsw.cmd.count; |
381 | } |
382 | if (dstat == 0x08) |
383 | break; |
384 | fallthrough; |
385 | case 0x04: |
386 | /* Device end interrupt. */ |
387 | if ((raw = req->info) == NULL) |
388 | goto put_tty; /* That shouldn't happen ... */ |
389 | if (req->type == RAW3215_READ && tty != NULL) { |
390 | unsigned int cchar; |
391 | |
392 | count = 160 - req->residual; |
393 | EBCASC(raw->inbuf, count); |
394 | cchar = ctrlchar_handle(buf: raw->inbuf, len: count, tty); |
395 | switch (cchar & CTRLCHAR_MASK) { |
396 | case CTRLCHAR_SYSRQ: |
397 | break; |
398 | |
399 | case CTRLCHAR_CTRL: |
400 | tty_insert_flip_char(port: &raw->port, ch: cchar, |
401 | TTY_NORMAL); |
402 | tty_flip_buffer_push(port: &raw->port); |
403 | break; |
404 | |
405 | case CTRLCHAR_NONE: |
406 | if (count < 2 || |
407 | (strncmp(raw->inbuf+count-2, "\252n" , 2) && |
408 | strncmp(raw->inbuf+count-2, "^n" , 2)) ) { |
409 | /* add the auto \n */ |
410 | raw->inbuf[count] = '\n'; |
411 | count++; |
412 | } else |
413 | count -= 2; |
414 | tty_insert_flip_string(port: &raw->port, chars: raw->inbuf, |
415 | size: count); |
416 | tty_flip_buffer_push(port: &raw->port); |
417 | break; |
418 | } |
419 | } else if (req->type == RAW3215_WRITE) { |
420 | raw->count -= req->len; |
421 | raw->written -= req->len; |
422 | } |
423 | raw->flags &= ~RAW3215_WORKING; |
424 | raw3215_free_req(req); |
425 | /* check for empty wait */ |
426 | if (waitqueue_active(wq_head: &raw->empty_wait) && |
427 | raw->queued_write == NULL && |
428 | raw->queued_read == NULL) { |
429 | wake_up_interruptible(&raw->empty_wait); |
430 | } |
431 | raw3215_next_io(raw, tty); |
432 | break; |
433 | default: |
434 | /* Strange interrupt, I'll do my best to clean up */ |
435 | if (req != NULL && req->type != RAW3215_FREE) { |
436 | if (req->type == RAW3215_WRITE) { |
437 | raw->count -= req->len; |
438 | raw->written -= req->len; |
439 | } |
440 | raw->flags &= ~RAW3215_WORKING; |
441 | raw3215_free_req(req); |
442 | } |
443 | raw3215_next_io(raw, tty); |
444 | } |
445 | put_tty: |
446 | tty_kref_put(tty); |
447 | } |
448 | |
449 | /* |
450 | * Need to drop data to avoid blocking. Drop as much data as possible. |
451 | * This is unqueued part in the buffer and the queued part in the request. |
452 | * Also adjust the head position to append new data and set count |
453 | * accordingly. |
454 | * |
455 | * Return number of bytes available in buffer. |
456 | */ |
457 | static unsigned int raw3215_drop(struct raw3215_info *raw) |
458 | { |
459 | struct raw3215_req *req; |
460 | |
461 | req = raw->queued_write; |
462 | if (req) { |
463 | /* Drop queued data and delete request */ |
464 | raw->written -= req->len; |
465 | raw3215_free_req(req); |
466 | raw->queued_write = NULL; |
467 | } |
468 | raw->head = (raw->head - raw->count + raw->written) & |
469 | (RAW3215_BUFFER_SIZE - 1); |
470 | raw->count = raw->written; |
471 | |
472 | return RAW3215_BUFFER_SIZE - raw->count; |
473 | } |
474 | |
475 | /* |
476 | * Wait until length bytes are available int the output buffer. |
477 | * If drop mode is active and wait condition holds true, start dropping |
478 | * data. |
479 | * Has to be called with the s390irq lock held. Can be called |
480 | * disabled. |
481 | */ |
482 | static unsigned int raw3215_make_room(struct raw3215_info *raw, |
483 | unsigned int length, bool drop) |
484 | { |
485 | while (RAW3215_BUFFER_SIZE - raw->count < length) { |
486 | if (drop) |
487 | return raw3215_drop(raw); |
488 | |
489 | /* there might be a request pending */ |
490 | raw->flags |= RAW3215_FLUSHING; |
491 | raw3215_mk_write_req(raw); |
492 | raw3215_try_io(raw); |
493 | raw->flags &= ~RAW3215_FLUSHING; |
494 | #ifdef CONFIG_TN3215_CONSOLE |
495 | ccw_device_wait_idle(raw->cdev); |
496 | #endif |
497 | /* Enough room freed up ? */ |
498 | if (RAW3215_BUFFER_SIZE - raw->count >= length) |
499 | break; |
500 | /* there might be another cpu waiting for the lock */ |
501 | spin_unlock(lock: get_ccwdev_lock(raw->cdev)); |
502 | udelay(100); |
503 | spin_lock(lock: get_ccwdev_lock(raw->cdev)); |
504 | } |
505 | return length; |
506 | } |
507 | |
508 | #define RAW3215_COUNT 1 |
509 | #define RAW3215_STORE 2 |
510 | |
511 | /* |
512 | * Add text to console buffer. Find tabs in input and calculate size |
513 | * including tab replacement. |
514 | * This function operates in 2 different modes, depending on parameter |
515 | * opmode: |
516 | * RAW3215_COUNT: Get the size needed for the input string with |
517 | * proper tab replacement calculation. |
518 | * Return value is the number of bytes required to store the |
519 | * input. However no data is actually stored. |
520 | * The parameter todrop is not used. |
521 | * RAW3215_STORE: Add data to the console buffer. The parameter todrop is |
522 | * valid and contains the number of bytes to be dropped from head of |
523 | * string without blocking. |
524 | * Return value is the number of bytes copied. |
525 | */ |
526 | static unsigned int raw3215_addtext(const char *str, unsigned int length, |
527 | struct raw3215_info *raw, int opmode, |
528 | unsigned int todrop) |
529 | { |
530 | unsigned int c, ch, i, blanks, expanded_size = 0; |
531 | unsigned int column = raw->line_pos; |
532 | |
533 | if (opmode == RAW3215_COUNT) |
534 | todrop = 0; |
535 | |
536 | for (c = 0; c < length; ++c) { |
537 | blanks = 1; |
538 | ch = str[c]; |
539 | |
540 | switch (ch) { |
541 | case '\n': |
542 | expanded_size++; |
543 | column = 0; |
544 | break; |
545 | case '\t': |
546 | blanks = TAB_STOP_SIZE - (column % TAB_STOP_SIZE); |
547 | column += blanks; |
548 | expanded_size += blanks; |
549 | ch = ' '; |
550 | break; |
551 | default: |
552 | expanded_size++; |
553 | column++; |
554 | break; |
555 | } |
556 | |
557 | if (opmode == RAW3215_COUNT) |
558 | continue; |
559 | if (todrop && expanded_size < todrop) /* Drop head data */ |
560 | continue; |
561 | for (i = 0; i < blanks; i++) { |
562 | raw->buffer[raw->head] = (char)_ascebc[(int)ch]; |
563 | raw->head = (raw->head + 1) & (RAW3215_BUFFER_SIZE - 1); |
564 | raw->count++; |
565 | } |
566 | raw->line_pos = column; |
567 | } |
568 | return expanded_size - todrop; |
569 | } |
570 | |
571 | /* |
572 | * String write routine for 3215 devices |
573 | */ |
574 | static void raw3215_write(struct raw3215_info *raw, const char *str, |
575 | unsigned int length) |
576 | { |
577 | unsigned int count, avail; |
578 | unsigned long flags; |
579 | |
580 | spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags); |
581 | |
582 | count = raw3215_addtext(str, length, raw, RAW3215_COUNT, todrop: 0); |
583 | |
584 | avail = raw3215_make_room(raw, length: count, drop: con3215_drop); |
585 | if (avail) { |
586 | raw3215_addtext(str, length, raw, RAW3215_STORE, |
587 | todrop: count - avail); |
588 | } |
589 | if (!(raw->flags & RAW3215_WORKING)) { |
590 | raw3215_mk_write_req(raw); |
591 | /* start or queue request */ |
592 | raw3215_try_io(raw); |
593 | } |
594 | spin_unlock_irqrestore(lock: get_ccwdev_lock(raw->cdev), flags); |
595 | } |
596 | |
597 | /* |
598 | * Put character routine for 3215 devices |
599 | */ |
600 | static void raw3215_putchar(struct raw3215_info *raw, unsigned char ch) |
601 | { |
602 | raw3215_write(raw, str: &ch, length: 1); |
603 | } |
604 | |
605 | /* |
606 | * Flush routine, it simply sets the flush flag and tries to start |
607 | * pending IO. |
608 | */ |
609 | static void raw3215_flush_buffer(struct raw3215_info *raw) |
610 | { |
611 | unsigned long flags; |
612 | |
613 | spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags); |
614 | if (raw->count > 0) { |
615 | raw->flags |= RAW3215_FLUSHING; |
616 | raw3215_try_io(raw); |
617 | raw->flags &= ~RAW3215_FLUSHING; |
618 | } |
619 | spin_unlock_irqrestore(lock: get_ccwdev_lock(raw->cdev), flags); |
620 | } |
621 | |
622 | /* |
623 | * Fire up a 3215 device. |
624 | */ |
625 | static int raw3215_startup(struct raw3215_info *raw) |
626 | { |
627 | unsigned long flags; |
628 | |
629 | if (tty_port_initialized(port: &raw->port)) |
630 | return 0; |
631 | raw->line_pos = 0; |
632 | tty_port_set_initialized(port: &raw->port, val: true); |
633 | spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags); |
634 | raw3215_try_io(raw); |
635 | spin_unlock_irqrestore(lock: get_ccwdev_lock(raw->cdev), flags); |
636 | |
637 | return 0; |
638 | } |
639 | |
640 | /* |
641 | * Shutdown a 3215 device. |
642 | */ |
643 | static void raw3215_shutdown(struct raw3215_info *raw) |
644 | { |
645 | DECLARE_WAITQUEUE(wait, current); |
646 | unsigned long flags; |
647 | |
648 | if (!tty_port_initialized(port: &raw->port) || (raw->flags & RAW3215_FIXED)) |
649 | return; |
650 | /* Wait for outstanding requests, then free irq */ |
651 | spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags); |
652 | if ((raw->flags & RAW3215_WORKING) || |
653 | raw->queued_write != NULL || |
654 | raw->queued_read != NULL) { |
655 | add_wait_queue(wq_head: &raw->empty_wait, wq_entry: &wait); |
656 | set_current_state(TASK_INTERRUPTIBLE); |
657 | spin_unlock_irqrestore(lock: get_ccwdev_lock(raw->cdev), flags); |
658 | schedule(); |
659 | spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags); |
660 | remove_wait_queue(wq_head: &raw->empty_wait, wq_entry: &wait); |
661 | set_current_state(TASK_RUNNING); |
662 | tty_port_set_initialized(port: &raw->port, val: true); |
663 | } |
664 | spin_unlock_irqrestore(lock: get_ccwdev_lock(raw->cdev), flags); |
665 | } |
666 | |
667 | static struct raw3215_info *raw3215_alloc_info(void) |
668 | { |
669 | struct raw3215_info *info; |
670 | |
671 | info = kzalloc(size: sizeof(struct raw3215_info), GFP_KERNEL | GFP_DMA); |
672 | if (!info) |
673 | return NULL; |
674 | |
675 | info->buffer = kzalloc(RAW3215_BUFFER_SIZE, GFP_KERNEL | GFP_DMA); |
676 | info->inbuf = kzalloc(RAW3215_INBUF_SIZE, GFP_KERNEL | GFP_DMA); |
677 | if (!info->buffer || !info->inbuf) { |
678 | kfree(objp: info->inbuf); |
679 | kfree(objp: info->buffer); |
680 | kfree(objp: info); |
681 | return NULL; |
682 | } |
683 | |
684 | timer_setup(&info->timer, raw3215_timeout, 0); |
685 | init_waitqueue_head(&info->empty_wait); |
686 | tty_port_init(port: &info->port); |
687 | |
688 | return info; |
689 | } |
690 | |
691 | static void raw3215_free_info(struct raw3215_info *raw) |
692 | { |
693 | kfree(objp: raw->inbuf); |
694 | kfree(objp: raw->buffer); |
695 | tty_port_destroy(port: &raw->port); |
696 | kfree(objp: raw); |
697 | } |
698 | |
699 | static int raw3215_probe(struct ccw_device *cdev) |
700 | { |
701 | struct raw3215_info *raw; |
702 | int line; |
703 | |
704 | /* Console is special. */ |
705 | if (raw3215[0] && (raw3215[0] == dev_get_drvdata(dev: &cdev->dev))) |
706 | return 0; |
707 | |
708 | raw = raw3215_alloc_info(); |
709 | if (raw == NULL) |
710 | return -ENOMEM; |
711 | |
712 | raw->cdev = cdev; |
713 | dev_set_drvdata(dev: &cdev->dev, data: raw); |
714 | cdev->handler = raw3215_irq; |
715 | |
716 | spin_lock(lock: &raw3215_device_lock); |
717 | for (line = 0; line < NR_3215; line++) { |
718 | if (!raw3215[line]) { |
719 | raw3215[line] = raw; |
720 | break; |
721 | } |
722 | } |
723 | spin_unlock(lock: &raw3215_device_lock); |
724 | if (line == NR_3215) { |
725 | raw3215_free_info(raw); |
726 | return -ENODEV; |
727 | } |
728 | |
729 | return 0; |
730 | } |
731 | |
732 | static void raw3215_remove(struct ccw_device *cdev) |
733 | { |
734 | struct raw3215_info *raw; |
735 | unsigned int line; |
736 | |
737 | ccw_device_set_offline(cdev); |
738 | raw = dev_get_drvdata(dev: &cdev->dev); |
739 | if (raw) { |
740 | spin_lock(lock: &raw3215_device_lock); |
741 | for (line = 0; line < NR_3215; line++) |
742 | if (raw3215[line] == raw) |
743 | break; |
744 | raw3215[line] = NULL; |
745 | spin_unlock(lock: &raw3215_device_lock); |
746 | dev_set_drvdata(dev: &cdev->dev, NULL); |
747 | raw3215_free_info(raw); |
748 | } |
749 | } |
750 | |
751 | static int raw3215_set_online(struct ccw_device *cdev) |
752 | { |
753 | struct raw3215_info *raw; |
754 | |
755 | raw = dev_get_drvdata(dev: &cdev->dev); |
756 | if (!raw) |
757 | return -ENODEV; |
758 | |
759 | return raw3215_startup(raw); |
760 | } |
761 | |
762 | static int raw3215_set_offline(struct ccw_device *cdev) |
763 | { |
764 | struct raw3215_info *raw; |
765 | |
766 | raw = dev_get_drvdata(dev: &cdev->dev); |
767 | if (!raw) |
768 | return -ENODEV; |
769 | |
770 | raw3215_shutdown(raw); |
771 | |
772 | return 0; |
773 | } |
774 | |
775 | static struct ccw_device_id raw3215_id[] = { |
776 | { CCW_DEVICE(0x3215, 0) }, |
777 | { /* end of list */ }, |
778 | }; |
779 | |
780 | static ssize_t con_drop_store(struct device_driver *dev, const char *buf, size_t count) |
781 | { |
782 | bool drop; |
783 | int rc; |
784 | |
785 | rc = kstrtobool(s: buf, res: &drop); |
786 | if (!rc) |
787 | con3215_drop = drop; |
788 | return rc ?: count; |
789 | } |
790 | |
791 | static ssize_t con_drop_show(struct device_driver *dev, char *buf) |
792 | { |
793 | return sysfs_emit(buf, fmt: "%d\n" , con3215_drop ? 1 : 0); |
794 | } |
795 | |
796 | static DRIVER_ATTR_RW(con_drop); |
797 | |
798 | static struct attribute *con3215_drv_attrs[] = { |
799 | &driver_attr_con_drop.attr, |
800 | NULL, |
801 | }; |
802 | |
803 | static struct attribute_group con3215_drv_attr_group = { |
804 | .attrs = con3215_drv_attrs, |
805 | NULL, |
806 | }; |
807 | |
808 | static const struct attribute_group *con3215_drv_attr_groups[] = { |
809 | &con3215_drv_attr_group, |
810 | NULL, |
811 | }; |
812 | |
813 | static struct ccw_driver raw3215_ccw_driver = { |
814 | .driver = { |
815 | .name = "3215" , |
816 | .groups = con3215_drv_attr_groups, |
817 | .owner = THIS_MODULE, |
818 | }, |
819 | .ids = raw3215_id, |
820 | .probe = &raw3215_probe, |
821 | .remove = &raw3215_remove, |
822 | .set_online = &raw3215_set_online, |
823 | .set_offline = &raw3215_set_offline, |
824 | .int_class = IRQIO_C15, |
825 | }; |
826 | |
827 | static void handle_write(struct raw3215_info *raw, const char *str, int count) |
828 | { |
829 | int i; |
830 | |
831 | while (count > 0) { |
832 | i = min_t(int, count, RAW3215_BUFFER_SIZE - 1); |
833 | raw3215_write(raw, str, length: i); |
834 | count -= i; |
835 | str += i; |
836 | } |
837 | } |
838 | |
839 | #ifdef CONFIG_TN3215_CONSOLE |
840 | /* |
841 | * Write a string to the 3215 console |
842 | */ |
843 | static void con3215_write(struct console *co, const char *str, unsigned int count) |
844 | { |
845 | handle_write(raw3215[0], str, count); |
846 | } |
847 | |
848 | static struct tty_driver *con3215_device(struct console *c, int *index) |
849 | { |
850 | *index = c->index; |
851 | return tty3215_driver; |
852 | } |
853 | |
854 | /* |
855 | * The below function is called as a panic/reboot notifier before the |
856 | * system enters a disabled, endless loop. |
857 | * |
858 | * Notice we must use the spin_trylock() alternative, to prevent lockups |
859 | * in atomic context (panic routine runs with secondary CPUs, local IRQs |
860 | * and preemption disabled). |
861 | */ |
862 | static int con3215_notify(struct notifier_block *self, |
863 | unsigned long event, void *data) |
864 | { |
865 | struct raw3215_info *raw; |
866 | unsigned long flags; |
867 | |
868 | raw = raw3215[0]; /* console 3215 is the first one */ |
869 | if (!spin_trylock_irqsave(get_ccwdev_lock(raw->cdev), flags)) |
870 | return NOTIFY_DONE; |
871 | raw3215_make_room(raw, RAW3215_BUFFER_SIZE, false); |
872 | spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags); |
873 | |
874 | return NOTIFY_DONE; |
875 | } |
876 | |
877 | static struct notifier_block on_panic_nb = { |
878 | .notifier_call = con3215_notify, |
879 | .priority = INT_MIN + 1, /* run the callback late */ |
880 | }; |
881 | |
882 | static struct notifier_block on_reboot_nb = { |
883 | .notifier_call = con3215_notify, |
884 | .priority = INT_MIN + 1, /* run the callback late */ |
885 | }; |
886 | |
887 | /* |
888 | * The console structure for the 3215 console |
889 | */ |
890 | static struct console con3215 = { |
891 | .name = "ttyS" , |
892 | .write = con3215_write, |
893 | .device = con3215_device, |
894 | .flags = CON_PRINTBUFFER, |
895 | }; |
896 | |
897 | /* |
898 | * 3215 console initialization code called from console_init(). |
899 | */ |
900 | static int __init con3215_init(void) |
901 | { |
902 | struct ccw_device *cdev; |
903 | struct raw3215_info *raw; |
904 | struct raw3215_req *req; |
905 | int i; |
906 | |
907 | /* Check if 3215 is to be the console */ |
908 | if (!CONSOLE_IS_3215) |
909 | return -ENODEV; |
910 | |
911 | /* Set the console mode for VM */ |
912 | if (MACHINE_IS_VM) { |
913 | cpcmd("TERM CONMODE 3215" , NULL, 0, NULL); |
914 | cpcmd("TERM AUTOCR OFF" , NULL, 0, NULL); |
915 | } |
916 | |
917 | /* allocate 3215 request structures */ |
918 | raw3215_freelist = NULL; |
919 | for (i = 0; i < NR_3215_REQ; i++) { |
920 | req = kzalloc(sizeof(struct raw3215_req), GFP_KERNEL | GFP_DMA); |
921 | if (!req) |
922 | return -ENOMEM; |
923 | req->next = raw3215_freelist; |
924 | raw3215_freelist = req; |
925 | } |
926 | |
927 | cdev = ccw_device_create_console(&raw3215_ccw_driver); |
928 | if (IS_ERR(cdev)) |
929 | return -ENODEV; |
930 | |
931 | raw3215[0] = raw = raw3215_alloc_info(); |
932 | raw->cdev = cdev; |
933 | dev_set_drvdata(&cdev->dev, raw); |
934 | cdev->handler = raw3215_irq; |
935 | |
936 | raw->flags |= RAW3215_FIXED; |
937 | if (ccw_device_enable_console(cdev)) { |
938 | ccw_device_destroy_console(cdev); |
939 | raw3215_free_info(raw); |
940 | raw3215[0] = NULL; |
941 | return -ENODEV; |
942 | } |
943 | |
944 | /* Request the console irq */ |
945 | if (raw3215_startup(raw) != 0) { |
946 | raw3215_free_info(raw); |
947 | raw3215[0] = NULL; |
948 | return -ENODEV; |
949 | } |
950 | atomic_notifier_chain_register(&panic_notifier_list, &on_panic_nb); |
951 | register_reboot_notifier(&on_reboot_nb); |
952 | register_console(&con3215); |
953 | return 0; |
954 | } |
955 | console_initcall(con3215_init); |
956 | #endif |
957 | |
958 | static int tty3215_install(struct tty_driver *driver, struct tty_struct *tty) |
959 | { |
960 | struct raw3215_info *raw; |
961 | |
962 | raw = raw3215[tty->index]; |
963 | if (raw == NULL) |
964 | return -ENODEV; |
965 | |
966 | tty->driver_data = raw; |
967 | |
968 | return tty_port_install(port: &raw->port, driver, tty); |
969 | } |
970 | |
971 | /* |
972 | * tty3215_open |
973 | * |
974 | * This routine is called whenever a 3215 tty is opened. |
975 | */ |
976 | static int tty3215_open(struct tty_struct *tty, struct file * filp) |
977 | { |
978 | struct raw3215_info *raw = tty->driver_data; |
979 | |
980 | tty_port_tty_set(port: &raw->port, tty); |
981 | |
982 | /* |
983 | * Start up 3215 device |
984 | */ |
985 | return raw3215_startup(raw); |
986 | } |
987 | |
988 | /* |
989 | * tty3215_close() |
990 | * |
991 | * This routine is called when the 3215 tty is closed. We wait |
992 | * for the remaining request to be completed. Then we clean up. |
993 | */ |
994 | static void tty3215_close(struct tty_struct *tty, struct file * filp) |
995 | { |
996 | struct raw3215_info *raw = tty->driver_data; |
997 | |
998 | if (raw == NULL || tty->count > 1) |
999 | return; |
1000 | tty->closing = 1; |
1001 | /* Shutdown the terminal */ |
1002 | raw3215_shutdown(raw); |
1003 | tty->closing = 0; |
1004 | tty_port_tty_set(port: &raw->port, NULL); |
1005 | } |
1006 | |
1007 | /* |
1008 | * Returns the amount of free space in the output buffer. |
1009 | */ |
1010 | static unsigned int tty3215_write_room(struct tty_struct *tty) |
1011 | { |
1012 | struct raw3215_info *raw = tty->driver_data; |
1013 | |
1014 | /* Subtract TAB_STOP_SIZE to allow for a tab, 8 <<< 64K */ |
1015 | if ((RAW3215_BUFFER_SIZE - raw->count - TAB_STOP_SIZE) >= 0) |
1016 | return RAW3215_BUFFER_SIZE - raw->count - TAB_STOP_SIZE; |
1017 | else |
1018 | return 0; |
1019 | } |
1020 | |
1021 | /* |
1022 | * String write routine for 3215 ttys |
1023 | */ |
1024 | static ssize_t tty3215_write(struct tty_struct *tty, const u8 *buf, |
1025 | size_t count) |
1026 | { |
1027 | handle_write(raw: tty->driver_data, str: buf, count); |
1028 | return count; |
1029 | } |
1030 | |
1031 | /* |
1032 | * Put character routine for 3215 ttys |
1033 | */ |
1034 | static int tty3215_put_char(struct tty_struct *tty, u8 ch) |
1035 | { |
1036 | struct raw3215_info *raw = tty->driver_data; |
1037 | |
1038 | raw3215_putchar(raw, ch); |
1039 | |
1040 | return 1; |
1041 | } |
1042 | |
1043 | static void tty3215_flush_chars(struct tty_struct *tty) |
1044 | { |
1045 | } |
1046 | |
1047 | /* |
1048 | * Returns the number of characters in the output buffer |
1049 | */ |
1050 | static unsigned int tty3215_chars_in_buffer(struct tty_struct *tty) |
1051 | { |
1052 | struct raw3215_info *raw = tty->driver_data; |
1053 | |
1054 | return raw->count; |
1055 | } |
1056 | |
1057 | static void tty3215_flush_buffer(struct tty_struct *tty) |
1058 | { |
1059 | struct raw3215_info *raw = tty->driver_data; |
1060 | |
1061 | raw3215_flush_buffer(raw); |
1062 | tty_wakeup(tty); |
1063 | } |
1064 | |
1065 | /* |
1066 | * Disable reading from a 3215 tty |
1067 | */ |
1068 | static void tty3215_throttle(struct tty_struct *tty) |
1069 | { |
1070 | struct raw3215_info *raw = tty->driver_data; |
1071 | |
1072 | raw->flags |= RAW3215_THROTTLED; |
1073 | } |
1074 | |
1075 | /* |
1076 | * Enable reading from a 3215 tty |
1077 | */ |
1078 | static void tty3215_unthrottle(struct tty_struct *tty) |
1079 | { |
1080 | struct raw3215_info *raw = tty->driver_data; |
1081 | unsigned long flags; |
1082 | |
1083 | if (raw->flags & RAW3215_THROTTLED) { |
1084 | spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags); |
1085 | raw->flags &= ~RAW3215_THROTTLED; |
1086 | raw3215_try_io(raw); |
1087 | spin_unlock_irqrestore(lock: get_ccwdev_lock(raw->cdev), flags); |
1088 | } |
1089 | } |
1090 | |
1091 | /* |
1092 | * Disable writing to a 3215 tty |
1093 | */ |
1094 | static void tty3215_stop(struct tty_struct *tty) |
1095 | { |
1096 | struct raw3215_info *raw = tty->driver_data; |
1097 | |
1098 | raw->flags |= RAW3215_STOPPED; |
1099 | } |
1100 | |
1101 | /* |
1102 | * Enable writing to a 3215 tty |
1103 | */ |
1104 | static void tty3215_start(struct tty_struct *tty) |
1105 | { |
1106 | struct raw3215_info *raw = tty->driver_data; |
1107 | unsigned long flags; |
1108 | |
1109 | if (raw->flags & RAW3215_STOPPED) { |
1110 | spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags); |
1111 | raw->flags &= ~RAW3215_STOPPED; |
1112 | raw3215_try_io(raw); |
1113 | spin_unlock_irqrestore(lock: get_ccwdev_lock(raw->cdev), flags); |
1114 | } |
1115 | } |
1116 | |
1117 | static const struct tty_operations tty3215_ops = { |
1118 | .install = tty3215_install, |
1119 | .open = tty3215_open, |
1120 | .close = tty3215_close, |
1121 | .write = tty3215_write, |
1122 | .put_char = tty3215_put_char, |
1123 | .flush_chars = tty3215_flush_chars, |
1124 | .write_room = tty3215_write_room, |
1125 | .chars_in_buffer = tty3215_chars_in_buffer, |
1126 | .flush_buffer = tty3215_flush_buffer, |
1127 | .throttle = tty3215_throttle, |
1128 | .unthrottle = tty3215_unthrottle, |
1129 | .stop = tty3215_stop, |
1130 | .start = tty3215_start, |
1131 | }; |
1132 | |
1133 | static int __init con3215_setup_drop(char *str) |
1134 | { |
1135 | bool drop; |
1136 | int rc; |
1137 | |
1138 | rc = kstrtobool(s: str, res: &drop); |
1139 | if (!rc) |
1140 | con3215_drop = drop; |
1141 | return rc; |
1142 | } |
1143 | early_param("con3215_drop" , con3215_setup_drop); |
1144 | |
1145 | /* |
1146 | * 3215 tty registration code called from tty_init(). |
1147 | * Most kernel services (incl. kmalloc) are available at this poimt. |
1148 | */ |
1149 | static int __init tty3215_init(void) |
1150 | { |
1151 | struct tty_driver *driver; |
1152 | int ret; |
1153 | |
1154 | if (!CONSOLE_IS_3215) |
1155 | return 0; |
1156 | |
1157 | driver = tty_alloc_driver(NR_3215, TTY_DRIVER_REAL_RAW); |
1158 | if (IS_ERR(ptr: driver)) |
1159 | return PTR_ERR(ptr: driver); |
1160 | |
1161 | ret = ccw_driver_register(&raw3215_ccw_driver); |
1162 | if (ret) { |
1163 | tty_driver_kref_put(driver); |
1164 | return ret; |
1165 | } |
1166 | /* |
1167 | * Initialize the tty_driver structure |
1168 | * Entries in tty3215_driver that are NOT initialized: |
1169 | * proc_entry, set_termios, flush_buffer, set_ldisc, write_proc |
1170 | */ |
1171 | |
1172 | driver->driver_name = "tty3215" ; |
1173 | driver->name = "ttyS" ; |
1174 | driver->major = TTY_MAJOR; |
1175 | driver->minor_start = 64; |
1176 | driver->type = TTY_DRIVER_TYPE_SYSTEM; |
1177 | driver->subtype = SYSTEM_TYPE_TTY; |
1178 | driver->init_termios = tty_std_termios; |
1179 | driver->init_termios.c_iflag = IGNBRK | IGNPAR; |
1180 | driver->init_termios.c_oflag = ONLCR; |
1181 | driver->init_termios.c_lflag = ISIG; |
1182 | tty_set_operations(driver, op: &tty3215_ops); |
1183 | ret = tty_register_driver(driver); |
1184 | if (ret) { |
1185 | tty_driver_kref_put(driver); |
1186 | return ret; |
1187 | } |
1188 | tty3215_driver = driver; |
1189 | return 0; |
1190 | } |
1191 | device_initcall(tty3215_init); |
1192 | |