4ed343e4eb4155718cc31084eb6902a2ee84f570
[firefly-linux-kernel-4.4.55.git] / drivers / s390 / char / con3215.c
1 /*
2  * 3215 line mode terminal driver.
3  *
4  * Copyright IBM Corp. 1999, 2009
5  * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
6  *
7  * Updated:
8  *  Aug-2000: Added tab support
9  *            Dan Morrison, IBM Corporation <dmorriso@cse.buffalo.edu>
10  */
11
12 #include <linux/module.h>
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/reboot.h>
23 #include <linux/serial.h> /* ASYNC_* flags */
24 #include <linux/slab.h>
25 #include <asm/ccwdev.h>
26 #include <asm/cio.h>
27 #include <asm/io.h>
28 #include <asm/ebcdic.h>
29 #include <asm/uaccess.h>
30 #include <asm/delay.h>
31 #include <asm/cpcmd.h>
32 #include <asm/setup.h>
33
34 #include "ctrlchar.h"
35
36 #define NR_3215             1
37 #define NR_3215_REQ         (4*NR_3215)
38 #define RAW3215_BUFFER_SIZE 65536     /* output buffer size */
39 #define RAW3215_INBUF_SIZE  256       /* input buffer size */
40 #define RAW3215_MIN_SPACE   128       /* minimum free space for wakeup */
41 #define RAW3215_MIN_WRITE   1024      /* min. length for immediate output */
42 #define RAW3215_MAX_BYTES   3968      /* max. bytes to write with one ssch */
43 #define RAW3215_MAX_NEWLINE 50        /* max. lines to write with one ssch */
44 #define RAW3215_NR_CCWS     3
45 #define RAW3215_TIMEOUT     HZ/10     /* time for delayed output */
46
47 #define RAW3215_WORKING     4         /* set if a request is being worked on */
48 #define RAW3215_THROTTLED   8         /* set if reading is disabled */
49 #define RAW3215_STOPPED     16        /* set if writing is disabled */
50 #define RAW3215_TIMER_RUNS  64        /* set if the output delay timer is on */
51 #define RAW3215_FLUSHING    128       /* set to flush buffer (no delay) */
52
53 #define TAB_STOP_SIZE       8         /* tab stop size */
54
55 /*
56  * Request types for a 3215 device
57  */
58 enum raw3215_type {
59         RAW3215_FREE, RAW3215_READ, RAW3215_WRITE
60 };
61
62 /*
63  * Request structure for a 3215 device
64  */
65 struct raw3215_req {
66         enum raw3215_type type;       /* type of the request */
67         int start, len;               /* start index & len in output buffer */
68         int delayable;                /* indication to wait for more data */
69         int residual;                 /* residual count for read request */
70         struct ccw1 ccws[RAW3215_NR_CCWS]; /* space for the channel program */
71         struct raw3215_info *info;    /* pointer to main structure */
72         struct raw3215_req *next;     /* pointer to next request */
73 } __attribute__ ((aligned(8)));
74
75 struct raw3215_info {
76         struct tty_port port;
77         struct ccw_device *cdev;      /* device for tty driver */
78         spinlock_t *lock;             /* pointer to irq lock */
79         int flags;                    /* state flags */
80         char *buffer;                 /* pointer to output buffer */
81         char *inbuf;                  /* pointer to input buffer */
82         int head;                     /* first free byte in output buffer */
83         int count;                    /* number of bytes in output buffer */
84         int written;                  /* number of bytes in write requests */
85         struct raw3215_req *queued_read; /* pointer to queued read requests */
86         struct raw3215_req *queued_write;/* pointer to queued write requests */
87         struct tasklet_struct tlet;   /* tasklet to invoke tty_wakeup */
88         wait_queue_head_t empty_wait; /* wait queue for flushing */
89         struct timer_list timer;      /* timer for delayed output */
90         int line_pos;                 /* position on the line (for tabs) */
91         char ubuffer[80];             /* copy_from_user buffer */
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 spinlock_t raw3215_freelist_lock;
102
103 static struct tty_driver *tty3215_driver;
104
105 /*
106  * Get a request structure from the free list
107  */
108 static inline struct raw3215_req *raw3215_alloc_req(void)
109 {
110         struct raw3215_req *req;
111         unsigned long flags;
112
113         spin_lock_irqsave(&raw3215_freelist_lock, flags);
114         req = raw3215_freelist;
115         raw3215_freelist = req->next;
116         spin_unlock_irqrestore(&raw3215_freelist_lock, flags);
117         return req;
118 }
119
120 /*
121  * Put a request structure back to the free list
122  */
123 static inline void raw3215_free_req(struct raw3215_req *req)
124 {
125         unsigned long flags;
126
127         if (req->type == RAW3215_FREE)
128                 return;         /* don't free a free request */
129         req->type = RAW3215_FREE;
130         spin_lock_irqsave(&raw3215_freelist_lock, flags);
131         req->next = raw3215_freelist;
132         raw3215_freelist = req;
133         spin_unlock_irqrestore(&raw3215_freelist_lock, flags);
134 }
135
136 /*
137  * Set up a read request that reads up to 160 byte from the 3215 device.
138  * If there is a queued read request it is used, but that shouldn't happen
139  * because a 3215 terminal won't accept a new read before the old one is
140  * completed.
141  */
142 static void raw3215_mk_read_req(struct raw3215_info *raw)
143 {
144         struct raw3215_req *req;
145         struct ccw1 *ccw;
146
147         /* there can only be ONE read request at a time */
148         req = raw->queued_read;
149         if (req == NULL) {
150                 /* no queued read request, use new req structure */
151                 req = raw3215_alloc_req();
152                 req->type = RAW3215_READ;
153                 req->info = raw;
154                 raw->queued_read = req;
155         }
156
157         ccw = req->ccws;
158         ccw->cmd_code = 0x0A; /* read inquiry */
159         ccw->flags = 0x20;    /* ignore incorrect length */
160         ccw->count = 160;
161         ccw->cda = (__u32) __pa(raw->inbuf);
162 }
163
164 /*
165  * Set up a write request with the information from the main structure.
166  * A ccw chain is created that writes as much as possible from the output
167  * buffer to the 3215 device. If a queued write exists it is replaced by
168  * the new, probably lengthened request.
169  */
170 static void raw3215_mk_write_req(struct raw3215_info *raw)
171 {
172         struct raw3215_req *req;
173         struct ccw1 *ccw;
174         int len, count, ix, lines;
175
176         if (raw->count <= raw->written)
177                 return;
178         /* check if there is a queued write request */
179         req = raw->queued_write;
180         if (req == NULL) {
181                 /* no queued write request, use new req structure */
182                 req = raw3215_alloc_req();
183                 req->type = RAW3215_WRITE;
184                 req->info = raw;
185                 raw->queued_write = req;
186         } else {
187                 raw->written -= req->len;
188         }
189
190         ccw = req->ccws;
191         req->start = (raw->head - raw->count + raw->written) &
192                      (RAW3215_BUFFER_SIZE - 1);
193         /*
194          * now we have to count newlines. We can at max accept
195          * RAW3215_MAX_NEWLINE newlines in a single ssch due to
196          * a restriction in VM
197          */
198         lines = 0;
199         ix = req->start;
200         while (lines < RAW3215_MAX_NEWLINE && ix != raw->head) {
201                 if (raw->buffer[ix] == 0x15)
202                         lines++;
203                 ix = (ix + 1) & (RAW3215_BUFFER_SIZE - 1);
204         }
205         len = ((ix - 1 - req->start) & (RAW3215_BUFFER_SIZE - 1)) + 1;
206         if (len > RAW3215_MAX_BYTES)
207                 len = RAW3215_MAX_BYTES;
208         req->len = len;
209         raw->written += len;
210
211         /* set the indication if we should try to enlarge this request */
212         req->delayable = (ix == raw->head) && (len < RAW3215_MIN_WRITE);
213
214         ix = req->start;
215         while (len > 0) {
216                 if (ccw > req->ccws)
217                         ccw[-1].flags |= 0x40; /* use command chaining */
218                 ccw->cmd_code = 0x01; /* write, auto carrier return */
219                 ccw->flags = 0x20;    /* ignore incorrect length ind.  */
220                 ccw->cda =
221                         (__u32) __pa(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(unsigned long __data)
285 {
286         struct raw3215_info *raw = (struct raw3215_info *) __data;
287         unsigned long flags;
288
289         spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags);
290         if (raw->flags & RAW3215_TIMER_RUNS) {
291                 del_timer(&raw->timer);
292                 raw->flags &= ~RAW3215_TIMER_RUNS;
293                 if (!(raw->port.flags & ASYNC_SUSPENDED)) {
294                         raw3215_mk_write_req(raw);
295                         raw3215_start_io(raw);
296                 }
297         }
298         spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags);
299 }
300
301 /*
302  * Function to conditionally start an IO. A read is started immediately,
303  * a write is only started immediately if the flush flag is on or the
304  * amount of data is bigger than RAW3215_MIN_WRITE. If a write is not
305  * done immediately a timer is started with a delay of RAW3215_TIMEOUT.
306  */
307 static inline void raw3215_try_io(struct raw3215_info *raw)
308 {
309         if (!(raw->port.flags & ASYNC_INITIALIZED) ||
310                         (raw->port.flags & ASYNC_SUSPENDED))
311                 return;
312         if (raw->queued_read != NULL)
313                 raw3215_start_io(raw);
314         else if (raw->queued_write != NULL) {
315                 if ((raw->queued_write->delayable == 0) ||
316                     (raw->flags & RAW3215_FLUSHING)) {
317                         /* execute write requests bigger than minimum size */
318                         raw3215_start_io(raw);
319                         if (raw->flags & RAW3215_TIMER_RUNS) {
320                                 del_timer(&raw->timer);
321                                 raw->flags &= ~RAW3215_TIMER_RUNS;
322                         }
323                 } else if (!(raw->flags & RAW3215_TIMER_RUNS)) {
324                         /* delay small writes */
325                         raw->timer.expires = RAW3215_TIMEOUT + jiffies;
326                         add_timer(&raw->timer);
327                         raw->flags |= RAW3215_TIMER_RUNS;
328                 }
329         }
330 }
331
332 /*
333  * Call tty_wakeup from tasklet context
334  */
335 static void raw3215_wakeup(unsigned long data)
336 {
337         struct raw3215_info *raw = (struct raw3215_info *) data;
338         struct tty_struct *tty;
339
340         tty = tty_port_tty_get(&raw->port);
341         if (tty) {
342                 tty_wakeup(tty);
343                 tty_kref_put(tty);
344         }
345 }
346
347 /*
348  * Try to start the next IO and wake up processes waiting on the tty.
349  */
350 static void raw3215_next_io(struct raw3215_info *raw, struct tty_struct *tty)
351 {
352         raw3215_mk_write_req(raw);
353         raw3215_try_io(raw);
354         if (tty && RAW3215_BUFFER_SIZE - raw->count >= RAW3215_MIN_SPACE)
355                 tasklet_schedule(&raw->tlet);
356 }
357
358 /*
359  * Interrupt routine, called from common io layer
360  */
361 static void raw3215_irq(struct ccw_device *cdev, unsigned long intparm,
362                         struct irb *irb)
363 {
364         struct raw3215_info *raw;
365         struct raw3215_req *req;
366         struct tty_struct *tty;
367         int cstat, dstat;
368         int count;
369
370         raw = dev_get_drvdata(&cdev->dev);
371         req = (struct raw3215_req *) intparm;
372         tty = tty_port_tty_get(&raw->port);
373         cstat = irb->scsw.cmd.cstat;
374         dstat = irb->scsw.cmd.dstat;
375         if (cstat != 0)
376                 raw3215_next_io(raw, tty);
377         if (dstat & 0x01) { /* we got a unit exception */
378                 dstat &= ~0x01;  /* we can ignore it */
379         }
380         switch (dstat) {
381         case 0x80:
382                 if (cstat != 0)
383                         break;
384                 /* Attention interrupt, someone hit the enter key */
385                 raw3215_mk_read_req(raw);
386                 raw3215_next_io(raw, tty);
387                 break;
388         case 0x08:
389         case 0x0C:
390                 /* Channel end interrupt. */
391                 if ((raw = req->info) == NULL)
392                         goto put_tty;        /* That shouldn't happen ... */
393                 if (req->type == RAW3215_READ) {
394                         /* store residual count, then wait for device end */
395                         req->residual = irb->scsw.cmd.count;
396                 }
397                 if (dstat == 0x08)
398                         break;
399         case 0x04:
400                 /* Device end interrupt. */
401                 if ((raw = req->info) == NULL)
402                         goto put_tty;        /* That shouldn't happen ... */
403                 if (req->type == RAW3215_READ && tty != NULL) {
404                         unsigned int cchar;
405
406                         count = 160 - req->residual;
407                         EBCASC(raw->inbuf, count);
408                         cchar = ctrlchar_handle(raw->inbuf, count, tty);
409                         switch (cchar & CTRLCHAR_MASK) {
410                         case CTRLCHAR_SYSRQ:
411                                 break;
412
413                         case CTRLCHAR_CTRL:
414                                 tty_insert_flip_char(tty, cchar, TTY_NORMAL);
415                                 tty_flip_buffer_push(tty);
416                                 break;
417
418                         case CTRLCHAR_NONE:
419                                 if (count < 2 ||
420                                     (strncmp(raw->inbuf+count-2, "\252n", 2) &&
421                                      strncmp(raw->inbuf+count-2, "^n", 2)) ) {
422                                         /* add the auto \n */
423                                         raw->inbuf[count] = '\n';
424                                         count++;
425                                 } else
426                                         count -= 2;
427                                 tty_insert_flip_string(tty, raw->inbuf, count);
428                                 tty_flip_buffer_push(tty);
429                                 break;
430                         }
431                 } else if (req->type == RAW3215_WRITE) {
432                         raw->count -= req->len;
433                         raw->written -= req->len;
434                 }
435                 raw->flags &= ~RAW3215_WORKING;
436                 raw3215_free_req(req);
437                 /* check for empty wait */
438                 if (waitqueue_active(&raw->empty_wait) &&
439                     raw->queued_write == NULL &&
440                     raw->queued_read == NULL) {
441                         wake_up_interruptible(&raw->empty_wait);
442                 }
443                 raw3215_next_io(raw, tty);
444                 break;
445         default:
446                 /* Strange interrupt, I'll do my best to clean up */
447                 if (req != NULL && req->type != RAW3215_FREE) {
448                         if (req->type == RAW3215_WRITE) {
449                                 raw->count -= req->len;
450                                 raw->written -= req->len;
451                         }
452                         raw->flags &= ~RAW3215_WORKING;
453                         raw3215_free_req(req);
454                 }
455                 raw3215_next_io(raw, tty);
456         }
457 put_tty:
458         tty_kref_put(tty);
459 }
460
461 /*
462  * Drop the oldest line from the output buffer.
463  */
464 static void raw3215_drop_line(struct raw3215_info *raw)
465 {
466         int ix;
467         char ch;
468
469         BUG_ON(raw->written != 0);
470         ix = (raw->head - raw->count) & (RAW3215_BUFFER_SIZE - 1);
471         while (raw->count > 0) {
472                 ch = raw->buffer[ix];
473                 ix = (ix + 1) & (RAW3215_BUFFER_SIZE - 1);
474                 raw->count--;
475                 if (ch == 0x15)
476                         break;
477         }
478         raw->head = ix;
479 }
480
481 /*
482  * Wait until length bytes are available int the output buffer.
483  * Has to be called with the s390irq lock held. Can be called
484  * disabled.
485  */
486 static void raw3215_make_room(struct raw3215_info *raw, unsigned int length)
487 {
488         while (RAW3215_BUFFER_SIZE - raw->count < length) {
489                 /* While console is frozen for suspend we have no other
490                  * choice but to drop message from the buffer to make
491                  * room for even more messages. */
492                 if (raw->port.flags & ASYNC_SUSPENDED) {
493                         raw3215_drop_line(raw);
494                         continue;
495                 }
496                 /* there might be a request pending */
497                 raw->flags |= RAW3215_FLUSHING;
498                 raw3215_mk_write_req(raw);
499                 raw3215_try_io(raw);
500                 raw->flags &= ~RAW3215_FLUSHING;
501 #ifdef CONFIG_TN3215_CONSOLE
502                 wait_cons_dev();
503 #endif
504                 /* Enough room freed up ? */
505                 if (RAW3215_BUFFER_SIZE - raw->count >= length)
506                         break;
507                 /* there might be another cpu waiting for the lock */
508                 spin_unlock(get_ccwdev_lock(raw->cdev));
509                 udelay(100);
510                 spin_lock(get_ccwdev_lock(raw->cdev));
511         }
512 }
513
514 /*
515  * String write routine for 3215 devices
516  */
517 static void raw3215_write(struct raw3215_info *raw, const char *str,
518                           unsigned int length)
519 {
520         unsigned long flags;
521         int c, count;
522
523         while (length > 0) {
524                 spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags);
525                 count = (length > RAW3215_BUFFER_SIZE) ?
526                                              RAW3215_BUFFER_SIZE : length;
527                 length -= count;
528
529                 raw3215_make_room(raw, count);
530
531                 /* copy string to output buffer and convert it to EBCDIC */
532                 while (1) {
533                         c = min_t(int, count,
534                                   min(RAW3215_BUFFER_SIZE - raw->count,
535                                       RAW3215_BUFFER_SIZE - raw->head));
536                         if (c <= 0)
537                                 break;
538                         memcpy(raw->buffer + raw->head, str, c);
539                         ASCEBC(raw->buffer + raw->head, c);
540                         raw->head = (raw->head + c) & (RAW3215_BUFFER_SIZE - 1);
541                         raw->count += c;
542                         raw->line_pos += c;
543                         str += c;
544                         count -= c;
545                 }
546                 if (!(raw->flags & RAW3215_WORKING)) {
547                         raw3215_mk_write_req(raw);
548                         /* start or queue request */
549                         raw3215_try_io(raw);
550                 }
551                 spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags);
552         }
553 }
554
555 /*
556  * Put character routine for 3215 devices
557  */
558 static void raw3215_putchar(struct raw3215_info *raw, unsigned char ch)
559 {
560         unsigned long flags;
561         unsigned int length, i;
562
563         spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags);
564         if (ch == '\t') {
565                 length = TAB_STOP_SIZE - (raw->line_pos%TAB_STOP_SIZE);
566                 raw->line_pos += length;
567                 ch = ' ';
568         } else if (ch == '\n') {
569                 length = 1;
570                 raw->line_pos = 0;
571         } else {
572                 length = 1;
573                 raw->line_pos++;
574         }
575         raw3215_make_room(raw, length);
576
577         for (i = 0; i < length; i++) {
578                 raw->buffer[raw->head] = (char) _ascebc[(int) ch];
579                 raw->head = (raw->head + 1) & (RAW3215_BUFFER_SIZE - 1);
580                 raw->count++;
581         }
582         if (!(raw->flags & RAW3215_WORKING)) {
583                 raw3215_mk_write_req(raw);
584                 /* start or queue request */
585                 raw3215_try_io(raw);
586         }
587         spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags);
588 }
589
590 /*
591  * Flush routine, it simply sets the flush flag and tries to start
592  * pending IO.
593  */
594 static void raw3215_flush_buffer(struct raw3215_info *raw)
595 {
596         unsigned long flags;
597
598         spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags);
599         if (raw->count > 0) {
600                 raw->flags |= RAW3215_FLUSHING;
601                 raw3215_try_io(raw);
602                 raw->flags &= ~RAW3215_FLUSHING;
603         }
604         spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags);
605 }
606
607 /*
608  * Fire up a 3215 device.
609  */
610 static int raw3215_startup(struct raw3215_info *raw)
611 {
612         unsigned long flags;
613
614         if (raw->port.flags & ASYNC_INITIALIZED)
615                 return 0;
616         raw->line_pos = 0;
617         raw->port.flags |= ASYNC_INITIALIZED;
618         spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags);
619         raw3215_try_io(raw);
620         spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags);
621
622         return 0;
623 }
624
625 /*
626  * Shutdown a 3215 device.
627  */
628 static void raw3215_shutdown(struct raw3215_info *raw)
629 {
630         DECLARE_WAITQUEUE(wait, current);
631         unsigned long flags;
632
633         if (!(raw->port.flags & ASYNC_INITIALIZED))
634                 return;
635         /* Wait for outstanding requests, then free irq */
636         spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags);
637         if ((raw->flags & RAW3215_WORKING) ||
638             raw->queued_write != NULL ||
639             raw->queued_read != NULL) {
640                 raw->port.flags |= ASYNC_CLOSING;
641                 add_wait_queue(&raw->empty_wait, &wait);
642                 set_current_state(TASK_INTERRUPTIBLE);
643                 spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags);
644                 schedule();
645                 spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags);
646                 remove_wait_queue(&raw->empty_wait, &wait);
647                 set_current_state(TASK_RUNNING);
648                 raw->port.flags &= ~(ASYNC_INITIALIZED | ASYNC_CLOSING);
649         }
650         spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags);
651 }
652
653 static struct raw3215_info *raw3215_alloc_info(void)
654 {
655         struct raw3215_info *info;
656
657         info = kzalloc(sizeof(struct raw3215_info), GFP_KERNEL | GFP_DMA);
658         if (!info)
659                 return NULL;
660
661         info->buffer = kzalloc(RAW3215_BUFFER_SIZE, GFP_KERNEL | GFP_DMA);
662         info->inbuf = kzalloc(RAW3215_INBUF_SIZE, GFP_KERNEL | GFP_DMA);
663         if (!info->buffer || !info->inbuf) {
664                 kfree(info);
665                 return NULL;
666         }
667
668         setup_timer(&info->timer, raw3215_timeout, (unsigned long)info);
669         init_waitqueue_head(&info->empty_wait);
670         tasklet_init(&info->tlet, raw3215_wakeup, (unsigned long)info);
671         tty_port_init(&info->port);
672
673         return info;
674 }
675
676 static void raw3215_free_info(struct raw3215_info *raw)
677 {
678         kfree(raw->inbuf);
679         kfree(raw->buffer);
680         kfree(raw);
681 }
682
683 static int raw3215_probe (struct ccw_device *cdev)
684 {
685         struct raw3215_info *raw;
686         int line;
687
688         /* Console is special. */
689         if (raw3215[0] && (raw3215[0] == dev_get_drvdata(&cdev->dev)))
690                 return 0;
691
692         raw = raw3215_alloc_info();
693         if (raw == NULL)
694                 return -ENOMEM;
695
696         raw->cdev = cdev;
697         dev_set_drvdata(&cdev->dev, raw);
698         cdev->handler = raw3215_irq;
699
700         spin_lock(&raw3215_device_lock);
701         for (line = 0; line < NR_3215; line++) {
702                 if (!raw3215[line]) {
703                         raw3215[line] = raw;
704                         break;
705                 }
706         }
707         spin_unlock(&raw3215_device_lock);
708         if (line == NR_3215) {
709                 raw3215_free_info(raw);
710                 return -ENODEV;
711         }
712
713         return 0;
714 }
715
716 static void raw3215_remove (struct ccw_device *cdev)
717 {
718         struct raw3215_info *raw;
719         unsigned int line;
720
721         ccw_device_set_offline(cdev);
722         raw = dev_get_drvdata(&cdev->dev);
723         if (raw) {
724                 spin_lock(&raw3215_device_lock);
725                 for (line = 0; line < NR_3215; line++)
726                         if (raw3215[line] == raw)
727                                 break;
728                 raw3215[line] = NULL;
729                 spin_unlock(&raw3215_device_lock);
730                 dev_set_drvdata(&cdev->dev, NULL);
731                 raw3215_free_info(raw);
732         }
733 }
734
735 static int raw3215_set_online (struct ccw_device *cdev)
736 {
737         struct raw3215_info *raw;
738
739         raw = dev_get_drvdata(&cdev->dev);
740         if (!raw)
741                 return -ENODEV;
742
743         return raw3215_startup(raw);
744 }
745
746 static int raw3215_set_offline (struct ccw_device *cdev)
747 {
748         struct raw3215_info *raw;
749
750         raw = dev_get_drvdata(&cdev->dev);
751         if (!raw)
752                 return -ENODEV;
753
754         raw3215_shutdown(raw);
755
756         return 0;
757 }
758
759 static int raw3215_pm_stop(struct ccw_device *cdev)
760 {
761         struct raw3215_info *raw;
762         unsigned long flags;
763
764         /* Empty the output buffer, then prevent new I/O. */
765         raw = dev_get_drvdata(&cdev->dev);
766         spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags);
767         raw3215_make_room(raw, RAW3215_BUFFER_SIZE);
768         raw->port.flags |= ASYNC_SUSPENDED;
769         spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags);
770         return 0;
771 }
772
773 static int raw3215_pm_start(struct ccw_device *cdev)
774 {
775         struct raw3215_info *raw;
776         unsigned long flags;
777
778         /* Allow I/O again and flush output buffer. */
779         raw = dev_get_drvdata(&cdev->dev);
780         spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags);
781         raw->port.flags &= ~ASYNC_SUSPENDED;
782         raw->flags |= RAW3215_FLUSHING;
783         raw3215_try_io(raw);
784         raw->flags &= ~RAW3215_FLUSHING;
785         spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags);
786         return 0;
787 }
788
789 static struct ccw_device_id raw3215_id[] = {
790         { CCW_DEVICE(0x3215, 0) },
791         { /* end of list */ },
792 };
793
794 static struct ccw_driver raw3215_ccw_driver = {
795         .driver = {
796                 .name   = "3215",
797                 .owner  = THIS_MODULE,
798         },
799         .ids            = raw3215_id,
800         .probe          = &raw3215_probe,
801         .remove         = &raw3215_remove,
802         .set_online     = &raw3215_set_online,
803         .set_offline    = &raw3215_set_offline,
804         .freeze         = &raw3215_pm_stop,
805         .thaw           = &raw3215_pm_start,
806         .restore        = &raw3215_pm_start,
807         .int_class      = IOINT_C15,
808 };
809
810 #ifdef CONFIG_TN3215_CONSOLE
811 /*
812  * Write a string to the 3215 console
813  */
814 static void con3215_write(struct console *co, const char *str,
815                           unsigned int count)
816 {
817         struct raw3215_info *raw;
818         int i;
819
820         if (count <= 0)
821                 return;
822         raw = raw3215[0];       /* console 3215 is the first one */
823         while (count > 0) {
824                 for (i = 0; i < count; i++)
825                         if (str[i] == '\t' || str[i] == '\n')
826                                 break;
827                 raw3215_write(raw, str, i);
828                 count -= i;
829                 str += i;
830                 if (count > 0) {
831                         raw3215_putchar(raw, *str);
832                         count--;
833                         str++;
834                 }
835         }
836 }
837
838 static struct tty_driver *con3215_device(struct console *c, int *index)
839 {
840         *index = c->index;
841         return tty3215_driver;
842 }
843
844 /*
845  * panic() calls con3215_flush through a panic_notifier
846  * before the system enters a disabled, endless loop.
847  */
848 static void con3215_flush(void)
849 {
850         struct raw3215_info *raw;
851         unsigned long flags;
852
853         raw = raw3215[0];  /* console 3215 is the first one */
854         if (raw->port.flags & ASYNC_SUSPENDED)
855                 /* The console is still frozen for suspend. */
856                 if (ccw_device_force_console())
857                         /* Forcing didn't work, no panic message .. */
858                         return;
859         spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags);
860         raw3215_make_room(raw, RAW3215_BUFFER_SIZE);
861         spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags);
862 }
863
864 static int con3215_notify(struct notifier_block *self,
865                           unsigned long event, void *data)
866 {
867         con3215_flush();
868         return NOTIFY_OK;
869 }
870
871 static struct notifier_block on_panic_nb = {
872         .notifier_call = con3215_notify,
873         .priority = 0,
874 };
875
876 static struct notifier_block on_reboot_nb = {
877         .notifier_call = con3215_notify,
878         .priority = 0,
879 };
880
881 /*
882  *  The console structure for the 3215 console
883  */
884 static struct console con3215 = {
885         .name    = "ttyS",
886         .write   = con3215_write,
887         .device  = con3215_device,
888         .flags   = CON_PRINTBUFFER,
889 };
890
891 /*
892  * 3215 console initialization code called from console_init().
893  */
894 static int __init con3215_init(void)
895 {
896         struct ccw_device *cdev;
897         struct raw3215_info *raw;
898         struct raw3215_req *req;
899         int i;
900
901         /* Check if 3215 is to be the console */
902         if (!CONSOLE_IS_3215)
903                 return -ENODEV;
904
905         /* Set the console mode for VM */
906         if (MACHINE_IS_VM) {
907                 cpcmd("TERM CONMODE 3215", NULL, 0, NULL);
908                 cpcmd("TERM AUTOCR OFF", NULL, 0, NULL);
909         }
910
911         /* allocate 3215 request structures */
912         raw3215_freelist = NULL;
913         spin_lock_init(&raw3215_freelist_lock);
914         for (i = 0; i < NR_3215_REQ; i++) {
915                 req = kzalloc(sizeof(struct raw3215_req), GFP_KERNEL | GFP_DMA);
916                 req->next = raw3215_freelist;
917                 raw3215_freelist = req;
918         }
919
920         cdev = ccw_device_probe_console();
921         if (IS_ERR(cdev))
922                 return -ENODEV;
923
924         raw3215[0] = raw = raw3215_alloc_info();
925         raw->cdev = cdev;
926         dev_set_drvdata(&cdev->dev, raw);
927         cdev->handler = raw3215_irq;
928
929         /* Request the console irq */
930         if (raw3215_startup(raw) != 0) {
931                 raw3215_free_info(raw);
932                 raw3215[0] = NULL;
933                 return -ENODEV;
934         }
935         atomic_notifier_chain_register(&panic_notifier_list, &on_panic_nb);
936         register_reboot_notifier(&on_reboot_nb);
937         register_console(&con3215);
938         return 0;
939 }
940 console_initcall(con3215_init);
941 #endif
942
943 static int tty3215_install(struct tty_driver *driver, struct tty_struct *tty)
944 {
945         struct raw3215_info *raw;
946
947         raw = raw3215[tty->index];
948         if (raw == NULL)
949                 return -ENODEV;
950
951         tty->driver_data = raw;
952
953         return tty_port_install(&raw->port, driver, tty);
954 }
955
956 /*
957  * tty3215_open
958  *
959  * This routine is called whenever a 3215 tty is opened.
960  */
961 static int tty3215_open(struct tty_struct *tty, struct file * filp)
962 {
963         struct raw3215_info *raw = tty->driver_data;
964         int retval;
965
966         tty_port_tty_set(&raw->port, tty);
967
968         tty->low_latency = 0;  /* don't use bottom half for pushing chars */
969         /*
970          * Start up 3215 device
971          */
972         retval = raw3215_startup(raw);
973         if (retval)
974                 return retval;
975
976         return 0;
977 }
978
979 /*
980  * tty3215_close()
981  *
982  * This routine is called when the 3215 tty is closed. We wait
983  * for the remaining request to be completed. Then we clean up.
984  */
985 static void tty3215_close(struct tty_struct *tty, struct file * filp)
986 {
987         struct raw3215_info *raw;
988
989         raw = (struct raw3215_info *) tty->driver_data;
990         if (raw == NULL || tty->count > 1)
991                 return;
992         tty->closing = 1;
993         /* Shutdown the terminal */
994         raw3215_shutdown(raw);
995         tasklet_kill(&raw->tlet);
996         tty->closing = 0;
997         tty_port_tty_set(&raw->port, NULL);
998 }
999
1000 /*
1001  * Returns the amount of free space in the output buffer.
1002  */
1003 static int tty3215_write_room(struct tty_struct *tty)
1004 {
1005         struct raw3215_info *raw;
1006
1007         raw = (struct raw3215_info *) tty->driver_data;
1008
1009         /* Subtract TAB_STOP_SIZE to allow for a tab, 8 <<< 64K */
1010         if ((RAW3215_BUFFER_SIZE - raw->count - TAB_STOP_SIZE) >= 0)
1011                 return RAW3215_BUFFER_SIZE - raw->count - TAB_STOP_SIZE;
1012         else
1013                 return 0;
1014 }
1015
1016 /*
1017  * String write routine for 3215 ttys
1018  */
1019 static int tty3215_write(struct tty_struct * tty,
1020                          const unsigned char *buf, int count)
1021 {
1022         struct raw3215_info *raw;
1023
1024         if (!tty)
1025                 return 0;
1026         raw = (struct raw3215_info *) tty->driver_data;
1027         raw3215_write(raw, 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, unsigned char ch)
1035 {
1036         struct raw3215_info *raw;
1037
1038         if (!tty)
1039                 return 0;
1040         raw = (struct raw3215_info *) tty->driver_data;
1041         raw3215_putchar(raw, ch);
1042         return 1;
1043 }
1044
1045 static void tty3215_flush_chars(struct tty_struct *tty)
1046 {
1047 }
1048
1049 /*
1050  * Returns the number of characters in the output buffer
1051  */
1052 static int tty3215_chars_in_buffer(struct tty_struct *tty)
1053 {
1054         struct raw3215_info *raw;
1055
1056         raw = (struct raw3215_info *) tty->driver_data;
1057         return raw->count;
1058 }
1059
1060 static void tty3215_flush_buffer(struct tty_struct *tty)
1061 {
1062         struct raw3215_info *raw;
1063
1064         raw = (struct raw3215_info *) tty->driver_data;
1065         raw3215_flush_buffer(raw);
1066         tty_wakeup(tty);
1067 }
1068
1069 /*
1070  * Disable reading from a 3215 tty
1071  */
1072 static void tty3215_throttle(struct tty_struct * tty)
1073 {
1074         struct raw3215_info *raw;
1075
1076         raw = (struct raw3215_info *) tty->driver_data;
1077         raw->flags |= RAW3215_THROTTLED;
1078 }
1079
1080 /*
1081  * Enable reading from a 3215 tty
1082  */
1083 static void tty3215_unthrottle(struct tty_struct * tty)
1084 {
1085         struct raw3215_info *raw;
1086         unsigned long flags;
1087
1088         raw = (struct raw3215_info *) tty->driver_data;
1089         if (raw->flags & RAW3215_THROTTLED) {
1090                 spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags);
1091                 raw->flags &= ~RAW3215_THROTTLED;
1092                 raw3215_try_io(raw);
1093                 spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags);
1094         }
1095 }
1096
1097 /*
1098  * Disable writing to a 3215 tty
1099  */
1100 static void tty3215_stop(struct tty_struct *tty)
1101 {
1102         struct raw3215_info *raw;
1103
1104         raw = (struct raw3215_info *) tty->driver_data;
1105         raw->flags |= RAW3215_STOPPED;
1106 }
1107
1108 /*
1109  * Enable writing to a 3215 tty
1110  */
1111 static void tty3215_start(struct tty_struct *tty)
1112 {
1113         struct raw3215_info *raw;
1114         unsigned long flags;
1115
1116         raw = (struct raw3215_info *) tty->driver_data;
1117         if (raw->flags & RAW3215_STOPPED) {
1118                 spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags);
1119                 raw->flags &= ~RAW3215_STOPPED;
1120                 raw3215_try_io(raw);
1121                 spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags);
1122         }
1123 }
1124
1125 static const struct tty_operations tty3215_ops = {
1126         .install = tty3215_install,
1127         .open = tty3215_open,
1128         .close = tty3215_close,
1129         .write = tty3215_write,
1130         .put_char = tty3215_put_char,
1131         .flush_chars = tty3215_flush_chars,
1132         .write_room = tty3215_write_room,
1133         .chars_in_buffer = tty3215_chars_in_buffer,
1134         .flush_buffer = tty3215_flush_buffer,
1135         .throttle = tty3215_throttle,
1136         .unthrottle = tty3215_unthrottle,
1137         .stop = tty3215_stop,
1138         .start = tty3215_start,
1139 };
1140
1141 /*
1142  * 3215 tty registration code called from tty_init().
1143  * Most kernel services (incl. kmalloc) are available at this poimt.
1144  */
1145 static int __init tty3215_init(void)
1146 {
1147         struct tty_driver *driver;
1148         int ret;
1149
1150         if (!CONSOLE_IS_3215)
1151                 return 0;
1152
1153         driver = alloc_tty_driver(NR_3215);
1154         if (!driver)
1155                 return -ENOMEM;
1156
1157         ret = ccw_driver_register(&raw3215_ccw_driver);
1158         if (ret) {
1159                 put_tty_driver(driver);
1160                 return ret;
1161         }
1162         /*
1163          * Initialize the tty_driver structure
1164          * Entries in tty3215_driver that are NOT initialized:
1165          * proc_entry, set_termios, flush_buffer, set_ldisc, write_proc
1166          */
1167
1168         driver->driver_name = "tty3215";
1169         driver->name = "ttyS";
1170         driver->major = TTY_MAJOR;
1171         driver->minor_start = 64;
1172         driver->type = TTY_DRIVER_TYPE_SYSTEM;
1173         driver->subtype = SYSTEM_TYPE_TTY;
1174         driver->init_termios = tty_std_termios;
1175         driver->init_termios.c_iflag = IGNBRK | IGNPAR;
1176         driver->init_termios.c_oflag = ONLCR | XTABS;
1177         driver->init_termios.c_lflag = ISIG;
1178         driver->flags = TTY_DRIVER_REAL_RAW;
1179         tty_set_operations(driver, &tty3215_ops);
1180         ret = tty_register_driver(driver);
1181         if (ret) {
1182                 put_tty_driver(driver);
1183                 return ret;
1184         }
1185         tty3215_driver = driver;
1186         return 0;
1187 }
1188
1189 static void __exit tty3215_exit(void)
1190 {
1191         tty_unregister_driver(tty3215_driver);
1192         put_tty_driver(tty3215_driver);
1193         ccw_driver_unregister(&raw3215_ccw_driver);
1194 }
1195
1196 module_init(tty3215_init);
1197 module_exit(tty3215_exit);