]> nv-tegra.nvidia Code Review - linux-2.6.git/blob - drivers/s390/char/con3215.c
Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux...
[linux-2.6.git] / drivers / s390 / char / con3215.c
1 /*
2  *  drivers/s390/char/con3215.c
3  *    3215 line mode terminal driver.
4  *
5  *  S390 version
6  *    Copyright (C) 1999,2000 IBM Deutschland Entwicklung GmbH, IBM Corporation
7  *    Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
8  *
9  *  Updated:
10  *   Aug-2000: Added tab support
11  *             Dan Morrison, IBM Corporation (dmorriso@cse.buffalo.edu)
12  */
13
14 #include <linux/module.h>
15 #include <linux/types.h>
16 #include <linux/kdev_t.h>
17 #include <linux/tty.h>
18 #include <linux/tty_flip.h>
19 #include <linux/vt_kern.h>
20 #include <linux/init.h>
21 #include <linux/console.h>
22 #include <linux/interrupt.h>
23 #include <linux/err.h>
24
25 #include <linux/slab.h>
26 #include <linux/bootmem.h>
27
28 #include <asm/ccwdev.h>
29 #include <asm/cio.h>
30 #include <asm/io.h>
31 #include <asm/ebcdic.h>
32 #include <asm/uaccess.h>
33 #include <asm/delay.h>
34 #include <asm/cpcmd.h>
35 #include <asm/setup.h>
36
37 #include "ctrlchar.h"
38
39 #define NR_3215             1
40 #define NR_3215_REQ         (4*NR_3215)
41 #define RAW3215_BUFFER_SIZE 65536     /* output buffer size */
42 #define RAW3215_INBUF_SIZE  256       /* input buffer size */
43 #define RAW3215_MIN_SPACE   128       /* minimum free space for wakeup */
44 #define RAW3215_MIN_WRITE   1024      /* min. length for immediate output */
45 #define RAW3215_MAX_BYTES   3968      /* max. bytes to write with one ssch */
46 #define RAW3215_MAX_NEWLINE 50        /* max. lines to write with one ssch */
47 #define RAW3215_NR_CCWS     3
48 #define RAW3215_TIMEOUT     HZ/10     /* time for delayed output */
49
50 #define RAW3215_FIXED       1         /* 3215 console device is not be freed */
51 #define RAW3215_ACTIVE      2         /* set if the device is in use */
52 #define RAW3215_WORKING     4         /* set if a request is being worked on */
53 #define RAW3215_THROTTLED   8         /* set if reading is disabled */
54 #define RAW3215_STOPPED     16        /* set if writing is disabled */
55 #define RAW3215_CLOSING     32        /* set while in close process */
56 #define RAW3215_TIMER_RUNS  64        /* set if the output delay timer is on */
57 #define RAW3215_FLUSHING    128       /* set to flush buffer (no delay) */
58
59 #define TAB_STOP_SIZE       8         /* tab stop size */
60
61 /*
62  * Request types for a 3215 device
63  */
64 enum raw3215_type {
65         RAW3215_FREE, RAW3215_READ, RAW3215_WRITE
66 };
67
68 /*
69  * Request structure for a 3215 device
70  */
71 struct raw3215_req {
72         enum raw3215_type type;       /* type of the request */
73         int start, len;               /* start index & len in output buffer */
74         int delayable;                /* indication to wait for more data */
75         int residual;                 /* residual count for read request */
76         struct ccw1 ccws[RAW3215_NR_CCWS]; /* space for the channel program */
77         struct raw3215_info *info;    /* pointer to main structure */
78         struct raw3215_req *next;     /* pointer to next request */
79 } __attribute__ ((aligned(8)));
80
81 struct raw3215_info {
82         struct ccw_device *cdev;      /* device for tty driver */
83         spinlock_t *lock;             /* pointer to irq lock */
84         int flags;                    /* state flags */
85         char *buffer;                 /* pointer to output buffer */
86         char *inbuf;                  /* pointer to input buffer */
87         int head;                     /* first free byte in output buffer */
88         int count;                    /* number of bytes in output buffer */
89         int written;                  /* number of bytes in write requests */
90         struct tty_struct *tty;       /* pointer to tty structure if present */
91         struct tasklet_struct tasklet;
92         struct raw3215_req *queued_read; /* pointer to queued read requests */
93         struct raw3215_req *queued_write;/* pointer to queued write requests */
94         wait_queue_head_t empty_wait; /* wait queue for flushing */
95         struct timer_list timer;      /* timer for delayed output */
96         char *message;                /* pending message from raw3215_irq */
97         int msg_dstat;                /* dstat for pending message */
98         int msg_cstat;                /* cstat for pending message */
99         int line_pos;                 /* position on the line (for tabs) */
100         char ubuffer[80];             /* copy_from_user buffer */
101 };
102
103 /* array of 3215 devices structures */
104 static struct raw3215_info *raw3215[NR_3215];
105 /* spinlock to protect the raw3215 array */
106 static DEFINE_SPINLOCK(raw3215_device_lock);
107 /* list of free request structures */
108 static struct raw3215_req *raw3215_freelist;
109 /* spinlock to protect free list */
110 static spinlock_t raw3215_freelist_lock;
111
112 static struct tty_driver *tty3215_driver;
113
114 /*
115  * Get a request structure from the free list
116  */
117 static inline struct raw3215_req *
118 raw3215_alloc_req(void) {
119         struct raw3215_req *req;
120         unsigned long flags;
121
122         spin_lock_irqsave(&raw3215_freelist_lock, flags);
123         req = raw3215_freelist;
124         raw3215_freelist = req->next;
125         spin_unlock_irqrestore(&raw3215_freelist_lock, flags);
126         return req;
127 }
128
129 /*
130  * Put a request structure back to the free list
131  */
132 static inline void
133 raw3215_free_req(struct raw3215_req *req) {
134         unsigned long flags;
135
136         if (req->type == RAW3215_FREE)
137                 return;         /* don't free a free request */
138         req->type = RAW3215_FREE;
139         spin_lock_irqsave(&raw3215_freelist_lock, flags);
140         req->next = raw3215_freelist;
141         raw3215_freelist = req;
142         spin_unlock_irqrestore(&raw3215_freelist_lock, flags);
143 }
144
145 /*
146  * Set up a read request that reads up to 160 byte from the 3215 device.
147  * If there is a queued read request it is used, but that shouldn't happen
148  * because a 3215 terminal won't accept a new read before the old one is
149  * completed.
150  */
151 static void
152 raw3215_mk_read_req(struct raw3215_info *raw)
153 {
154         struct raw3215_req *req;
155         struct ccw1 *ccw;
156
157         /* there can only be ONE read request at a time */
158         req = raw->queued_read;
159         if (req == NULL) {
160                 /* no queued read request, use new req structure */
161                 req = raw3215_alloc_req();
162                 req->type = RAW3215_READ;
163                 req->info = raw;
164                 raw->queued_read = req;
165         }
166
167         ccw = req->ccws;
168         ccw->cmd_code = 0x0A; /* read inquiry */
169         ccw->flags = 0x20;    /* ignore incorrect length */
170         ccw->count = 160;
171         ccw->cda = (__u32) __pa(raw->inbuf);
172 }
173
174 /*
175  * Set up a write request with the information from the main structure.
176  * A ccw chain is created that writes as much as possible from the output
177  * buffer to the 3215 device. If a queued write exists it is replaced by
178  * the new, probably lengthened request.
179  */
180 static void
181 raw3215_mk_write_req(struct raw3215_info *raw)
182 {
183         struct raw3215_req *req;
184         struct ccw1 *ccw;
185         int len, count, ix, lines;
186
187         if (raw->count <= raw->written)
188                 return;
189         /* check if there is a queued write request */
190         req = raw->queued_write;
191         if (req == NULL) {
192                 /* no queued write request, use new req structure */
193                 req = raw3215_alloc_req();
194                 req->type = RAW3215_WRITE;
195                 req->info = raw;
196                 raw->queued_write = req;
197         } else {
198                 raw->written -= req->len;
199         }
200
201         ccw = req->ccws;
202         req->start = (raw->head - raw->count + raw->written) &
203                      (RAW3215_BUFFER_SIZE - 1);
204         /*
205          * now we have to count newlines. We can at max accept
206          * RAW3215_MAX_NEWLINE newlines in a single ssch due to
207          * a restriction in VM
208          */
209         lines = 0;
210         ix = req->start;
211         while (lines < RAW3215_MAX_NEWLINE && ix != raw->head) {
212                 if (raw->buffer[ix] == 0x15)
213                         lines++;
214                 ix = (ix + 1) & (RAW3215_BUFFER_SIZE - 1);
215         }
216         len = ((ix - 1 - req->start) & (RAW3215_BUFFER_SIZE - 1)) + 1;
217         if (len > RAW3215_MAX_BYTES)
218                 len = RAW3215_MAX_BYTES;
219         req->len = len;
220         raw->written += len;
221
222         /* set the indication if we should try to enlarge this request */
223         req->delayable = (ix == raw->head) && (len < RAW3215_MIN_WRITE);
224
225         ix = req->start;
226         while (len > 0) {
227                 if (ccw > req->ccws)
228                         ccw[-1].flags |= 0x40; /* use command chaining */
229                 ccw->cmd_code = 0x01; /* write, auto carrier return */
230                 ccw->flags = 0x20;    /* ignore incorrect length ind.  */
231                 ccw->cda =
232                         (__u32) __pa(raw->buffer + ix);
233                 count = len;
234                 if (ix + count > RAW3215_BUFFER_SIZE)
235                         count = RAW3215_BUFFER_SIZE - ix;
236                 ccw->count = count;
237                 len -= count;
238                 ix = (ix + count) & (RAW3215_BUFFER_SIZE - 1);
239                 ccw++;
240         }
241         /*
242          * Add a NOP to the channel program. 3215 devices are purely
243          * emulated and its much better to avoid the channel end
244          * interrupt in this case.
245          */
246         if (ccw > req->ccws)
247                 ccw[-1].flags |= 0x40; /* use command chaining */
248         ccw->cmd_code = 0x03; /* NOP */
249         ccw->flags = 0;
250         ccw->cda = 0;
251         ccw->count = 1;
252 }
253
254 /*
255  * Start a read or a write request
256  */
257 static void
258 raw3215_start_io(struct raw3215_info *raw)
259 {
260         struct raw3215_req *req;
261         int res;
262
263         req = raw->queued_read;
264         if (req != NULL &&
265             !(raw->flags & (RAW3215_WORKING | RAW3215_THROTTLED))) {
266                 /* dequeue request */
267                 raw->queued_read = NULL;
268                 res = ccw_device_start(raw->cdev, req->ccws,
269                                        (unsigned long) req, 0, 0);
270                 if (res != 0) {
271                         /* do_IO failed, put request back to queue */
272                         raw->queued_read = req;
273                 } else {
274                         raw->flags |= RAW3215_WORKING;
275                 }
276         }
277         req = raw->queued_write;
278         if (req != NULL &&
279             !(raw->flags & (RAW3215_WORKING | RAW3215_STOPPED))) {
280                 /* dequeue request */
281                 raw->queued_write = NULL;
282                 res = ccw_device_start(raw->cdev, req->ccws,
283                                        (unsigned long) req, 0, 0);
284                 if (res != 0) {
285                         /* do_IO failed, put request back to queue */
286                         raw->queued_write = req;
287                 } else {
288                         raw->flags |= RAW3215_WORKING;
289                 }
290         }
291 }
292
293 /*
294  * Function to start a delayed output after RAW3215_TIMEOUT seconds
295  */
296 static void
297 raw3215_timeout(unsigned long __data)
298 {
299         struct raw3215_info *raw = (struct raw3215_info *) __data;
300         unsigned long flags;
301
302         spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags);
303         if (raw->flags & RAW3215_TIMER_RUNS) {
304                 del_timer(&raw->timer);
305                 raw->flags &= ~RAW3215_TIMER_RUNS;
306                 raw3215_mk_write_req(raw);
307                 raw3215_start_io(raw);
308         }
309         spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags);
310 }
311
312 /*
313  * Function to conditionally start an IO. A read is started immediately,
314  * a write is only started immediately if the flush flag is on or the
315  * amount of data is bigger than RAW3215_MIN_WRITE. If a write is not
316  * done immediately a timer is started with a delay of RAW3215_TIMEOUT.
317  */
318 static inline void
319 raw3215_try_io(struct raw3215_info *raw)
320 {
321         if (!(raw->flags & RAW3215_ACTIVE))
322                 return;
323         if (raw->queued_read != NULL)
324                 raw3215_start_io(raw);
325         else if (raw->queued_write != NULL) {
326                 if ((raw->queued_write->delayable == 0) ||
327                     (raw->flags & RAW3215_FLUSHING)) {
328                         /* execute write requests bigger than minimum size */
329                         raw3215_start_io(raw);
330                         if (raw->flags & RAW3215_TIMER_RUNS) {
331                                 del_timer(&raw->timer);
332                                 raw->flags &= ~RAW3215_TIMER_RUNS;
333                         }
334                 } else if (!(raw->flags & RAW3215_TIMER_RUNS)) {
335                         /* delay small writes */
336                         init_timer(&raw->timer);
337                         raw->timer.expires = RAW3215_TIMEOUT + jiffies;
338                         raw->timer.data = (unsigned long) raw;
339                         raw->timer.function = raw3215_timeout;
340                         add_timer(&raw->timer);
341                         raw->flags |= RAW3215_TIMER_RUNS;
342                 }
343         }
344 }
345
346 /*
347  * The bottom half handler routine for 3215 devices. It tries to start
348  * the next IO and wakes up processes waiting on the tty.
349  */
350 static void
351 raw3215_tasklet(void *data)
352 {
353         struct raw3215_info *raw;
354         struct tty_struct *tty;
355         unsigned long flags;
356
357         raw = (struct raw3215_info *) data;
358         spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags);
359         raw3215_mk_write_req(raw);
360         raw3215_try_io(raw);
361         spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags);
362         /* Check for pending message from raw3215_irq */
363         if (raw->message != NULL) {
364                 printk(raw->message, raw->msg_dstat, raw->msg_cstat);
365                 raw->message = NULL;
366         }
367         tty = raw->tty;
368         if (tty != NULL &&
369             RAW3215_BUFFER_SIZE - raw->count >= RAW3215_MIN_SPACE) {
370                 tty_wakeup(tty);
371         }
372 }
373
374 /*
375  * Interrupt routine, called from common io layer
376  */
377 static void
378 raw3215_irq(struct ccw_device *cdev, unsigned long intparm, struct irb *irb)
379 {
380         struct raw3215_info *raw;
381         struct raw3215_req *req;
382         struct tty_struct *tty;
383         int cstat, dstat;
384         int count, slen;
385
386         raw = cdev->dev.driver_data;
387         req = (struct raw3215_req *) intparm;
388         cstat = irb->scsw.cstat;
389         dstat = irb->scsw.dstat;
390         if (cstat != 0) {
391                 raw->message = KERN_WARNING
392                         "Got nonzero channel status in raw3215_irq "
393                         "(dev sts 0x%2x, sch sts 0x%2x)";
394                 raw->msg_dstat = dstat;
395                 raw->msg_cstat = cstat;
396                 tasklet_schedule(&raw->tasklet);
397         }
398         if (dstat & 0x01) { /* we got a unit exception */
399                 dstat &= ~0x01;  /* we can ignore it */
400         }
401         switch (dstat) {
402         case 0x80:
403                 if (cstat != 0)
404                         break;
405                 /* Attention interrupt, someone hit the enter key */
406                 raw3215_mk_read_req(raw);
407                 if (MACHINE_IS_P390)
408                         memset(raw->inbuf, 0, RAW3215_INBUF_SIZE);
409                 tasklet_schedule(&raw->tasklet);
410                 break;
411         case 0x08:
412         case 0x0C:
413                 /* Channel end interrupt. */
414                 if ((raw = req->info) == NULL)
415                         return;              /* That shouldn't happen ... */
416                 if (req->type == RAW3215_READ) {
417                         /* store residual count, then wait for device end */
418                         req->residual = irb->scsw.count;
419                 }
420                 if (dstat == 0x08)
421                         break;
422         case 0x04:
423                 /* Device end interrupt. */
424                 if ((raw = req->info) == NULL)
425                         return;              /* That shouldn't happen ... */
426                 if (req->type == RAW3215_READ && raw->tty != NULL) {
427                         unsigned int cchar;
428
429                         tty = raw->tty;
430                         count = 160 - req->residual;
431                         if (MACHINE_IS_P390) {
432                                 slen = strnlen(raw->inbuf, RAW3215_INBUF_SIZE);
433                                 if (count > slen)
434                                         count = slen;
435                         } else
436                         EBCASC(raw->inbuf, count);
437                         cchar = ctrlchar_handle(raw->inbuf, count, tty);
438                         switch (cchar & CTRLCHAR_MASK) {
439                         case CTRLCHAR_SYSRQ:
440                                 break;
441
442                         case CTRLCHAR_CTRL:
443                                 tty_insert_flip_char(tty, cchar, TTY_NORMAL);
444                                 tty_flip_buffer_push(raw->tty);
445                                 break;
446
447                         case CTRLCHAR_NONE:
448                                 if (count < 2 ||
449                                     (strncmp(raw->inbuf+count-2, "\252n", 2) &&
450                                      strncmp(raw->inbuf+count-2, "^n", 2)) ) {
451                                         /* add the auto \n */
452                                         raw->inbuf[count] = '\n';
453                                         count++;
454                                 } else
455                                         count -= 2;
456                                 tty_insert_flip_string(tty, raw->inbuf, count);
457                                 tty_flip_buffer_push(raw->tty);
458                                 break;
459                         }
460                 } else if (req->type == RAW3215_WRITE) {
461                         raw->count -= req->len;
462                         raw->written -= req->len;
463                 }
464                 raw->flags &= ~RAW3215_WORKING;
465                 raw3215_free_req(req);
466                 /* check for empty wait */
467                 if (waitqueue_active(&raw->empty_wait) &&
468                     raw->queued_write == NULL &&
469                     raw->queued_read == NULL) {
470                         wake_up_interruptible(&raw->empty_wait);
471                 }
472                 tasklet_schedule(&raw->tasklet);
473                 break;
474         default:
475                 /* Strange interrupt, I'll do my best to clean up */
476                 if (req != NULL && req->type != RAW3215_FREE) {
477                         if (req->type == RAW3215_WRITE) {
478                                 raw->count -= req->len;
479                                 raw->written -= req->len;
480                         }
481                         raw->flags &= ~RAW3215_WORKING;
482                         raw3215_free_req(req);
483                 }
484                 raw->message = KERN_WARNING
485                         "Spurious interrupt in in raw3215_irq "
486                         "(dev sts 0x%2x, sch sts 0x%2x)";
487                 raw->msg_dstat = dstat;
488                 raw->msg_cstat = cstat;
489                 tasklet_schedule(&raw->tasklet);
490         }
491         return;
492 }
493
494 /*
495  * Wait until length bytes are available int the output buffer.
496  * Has to be called with the s390irq lock held. Can be called
497  * disabled.
498  */
499 static void
500 raw3215_make_room(struct raw3215_info *raw, unsigned int length)
501 {
502         while (RAW3215_BUFFER_SIZE - raw->count < length) {
503                 /* there might be a request pending */
504                 raw->flags |= RAW3215_FLUSHING;
505                 raw3215_mk_write_req(raw);
506                 raw3215_try_io(raw);
507                 raw->flags &= ~RAW3215_FLUSHING;
508 #ifdef CONFIG_TN3215_CONSOLE
509                 wait_cons_dev();
510 #endif
511                 /* Enough room freed up ? */
512                 if (RAW3215_BUFFER_SIZE - raw->count >= length)
513                         break;
514                 /* there might be another cpu waiting for the lock */
515                 spin_unlock(get_ccwdev_lock(raw->cdev));
516                 udelay(100);
517                 spin_lock(get_ccwdev_lock(raw->cdev));
518         }
519 }
520
521 /*
522  * String write routine for 3215 devices
523  */
524 static void
525 raw3215_write(struct raw3215_info *raw, const char *str, unsigned int length)
526 {
527         unsigned long flags;
528         int c, count;
529
530         while (length > 0) {
531                 spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags);
532                 count = (length > RAW3215_BUFFER_SIZE) ?
533                                              RAW3215_BUFFER_SIZE : length;
534                 length -= count;
535
536                 raw3215_make_room(raw, count);
537
538                 /* copy string to output buffer and convert it to EBCDIC */
539                 while (1) {
540                         c = min_t(int, count,
541                                   min(RAW3215_BUFFER_SIZE - raw->count,
542                                       RAW3215_BUFFER_SIZE - raw->head));
543                         if (c <= 0)
544                                 break;
545                         memcpy(raw->buffer + raw->head, str, c);
546                         ASCEBC(raw->buffer + raw->head, c);
547                         raw->head = (raw->head + c) & (RAW3215_BUFFER_SIZE - 1);
548                         raw->count += c;
549                         raw->line_pos += c;
550                         str += c;
551                         count -= c;
552                 }
553                 if (!(raw->flags & RAW3215_WORKING)) {
554                         raw3215_mk_write_req(raw);
555                         /* start or queue request */
556                         raw3215_try_io(raw);
557                 }
558                 spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags);
559         }
560 }
561
562 /*
563  * Put character routine for 3215 devices
564  */
565 static void
566 raw3215_putchar(struct raw3215_info *raw, unsigned char ch)
567 {
568         unsigned long flags;
569         unsigned int length, i;
570
571         spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags);
572         if (ch == '\t') {
573                 length = TAB_STOP_SIZE - (raw->line_pos%TAB_STOP_SIZE);
574                 raw->line_pos += length;
575                 ch = ' ';
576         } else if (ch == '\n') {
577                 length = 1;
578                 raw->line_pos = 0;
579         } else {
580                 length = 1;
581                 raw->line_pos++;
582         }
583         raw3215_make_room(raw, length);
584
585         for (i = 0; i < length; i++) {
586                 raw->buffer[raw->head] = (char) _ascebc[(int) ch];
587                 raw->head = (raw->head + 1) & (RAW3215_BUFFER_SIZE - 1);
588                 raw->count++;
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(get_ccwdev_lock(raw->cdev), flags);
596 }
597
598 /*
599  * Flush routine, it simply sets the flush flag and tries to start
600  * pending IO.
601  */
602 static void
603 raw3215_flush_buffer(struct raw3215_info *raw)
604 {
605         unsigned long flags;
606
607         spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags);
608         if (raw->count > 0) {
609                 raw->flags |= RAW3215_FLUSHING;
610                 raw3215_try_io(raw);
611                 raw->flags &= ~RAW3215_FLUSHING;
612         }
613         spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags);
614 }
615
616 /*
617  * Fire up a 3215 device.
618  */
619 static int
620 raw3215_startup(struct raw3215_info *raw)
621 {
622         unsigned long flags;
623
624         if (raw->flags & RAW3215_ACTIVE)
625                 return 0;
626         raw->line_pos = 0;
627         raw->flags |= RAW3215_ACTIVE;
628         spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags);
629         raw3215_try_io(raw);
630         spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags);
631
632         return 0;
633 }
634
635 /*
636  * Shutdown a 3215 device.
637  */
638 static void
639 raw3215_shutdown(struct raw3215_info *raw)
640 {
641         DECLARE_WAITQUEUE(wait, current);
642         unsigned long flags;
643
644         if (!(raw->flags & RAW3215_ACTIVE) || (raw->flags & RAW3215_FIXED))
645                 return;
646         /* Wait for outstanding requests, then free irq */
647         spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags);
648         if ((raw->flags & RAW3215_WORKING) ||
649             raw->queued_write != NULL ||
650             raw->queued_read != NULL) {
651                 raw->flags |= RAW3215_CLOSING;
652                 add_wait_queue(&raw->empty_wait, &wait);
653                 set_current_state(TASK_INTERRUPTIBLE);
654                 spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags);
655                 schedule();
656                 spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags);
657                 remove_wait_queue(&raw->empty_wait, &wait);
658                 set_current_state(TASK_RUNNING);
659                 raw->flags &= ~(RAW3215_ACTIVE | RAW3215_CLOSING);
660         }
661         spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags);
662 }
663
664 static int
665 raw3215_probe (struct ccw_device *cdev)
666 {
667         struct raw3215_info *raw;
668         int line;
669
670         /* Console is special. */
671         if (raw3215[0] && (cdev->dev.driver_data == raw3215[0]))
672                 return 0;
673         raw = kmalloc(sizeof(struct raw3215_info) +
674                       RAW3215_INBUF_SIZE, GFP_KERNEL|GFP_DMA);
675         if (raw == NULL)
676                 return -ENOMEM;
677
678         spin_lock(&raw3215_device_lock);
679         for (line = 0; line < NR_3215; line++) {
680                 if (!raw3215[line]) {
681                         raw3215[line] = raw;
682                         break;
683                 }
684         }
685         spin_unlock(&raw3215_device_lock);
686         if (line == NR_3215) {
687                 kfree(raw);
688                 return -ENODEV;
689         }
690
691         raw->cdev = cdev;
692         raw->inbuf = (char *) raw + sizeof(struct raw3215_info);
693         memset(raw, 0, sizeof(struct raw3215_info));
694         raw->buffer = kmalloc(RAW3215_BUFFER_SIZE,
695                                        GFP_KERNEL|GFP_DMA);
696         if (raw->buffer == NULL) {
697                 spin_lock(&raw3215_device_lock);
698                 raw3215[line] = NULL;
699                 spin_unlock(&raw3215_device_lock);
700                 kfree(raw);
701                 return -ENOMEM;
702         }
703         tasklet_init(&raw->tasklet,
704                      (void (*)(unsigned long)) raw3215_tasklet,
705                      (unsigned long) raw);
706         init_waitqueue_head(&raw->empty_wait);
707
708         cdev->dev.driver_data = raw;
709         cdev->handler = raw3215_irq;
710
711         return 0;
712 }
713
714 static void
715 raw3215_remove (struct ccw_device *cdev)
716 {
717         struct raw3215_info *raw;
718
719         ccw_device_set_offline(cdev);
720         raw = cdev->dev.driver_data;
721         if (raw) {
722                 cdev->dev.driver_data = NULL;
723                 kfree(raw->buffer);
724                 kfree(raw);
725         }
726 }
727
728 static int
729 raw3215_set_online (struct ccw_device *cdev)
730 {
731         struct raw3215_info *raw;
732
733         raw = cdev->dev.driver_data;
734         if (!raw)
735                 return -ENODEV;
736
737         return raw3215_startup(raw);
738 }
739
740 static int
741 raw3215_set_offline (struct ccw_device *cdev)
742 {
743         struct raw3215_info *raw;
744
745         raw = cdev->dev.driver_data;
746         if (!raw)
747                 return -ENODEV;
748
749         raw3215_shutdown(raw);
750
751         return 0;
752 }
753
754 static struct ccw_device_id raw3215_id[] = {
755         { CCW_DEVICE(0x3215, 0) },
756         { /* end of list */ },
757 };
758
759 static struct ccw_driver raw3215_ccw_driver = {
760         .name           = "3215",
761         .owner          = THIS_MODULE,
762         .ids            = raw3215_id,
763         .probe          = &raw3215_probe,
764         .remove         = &raw3215_remove,
765         .set_online     = &raw3215_set_online,
766         .set_offline    = &raw3215_set_offline,
767 };
768
769 #ifdef CONFIG_TN3215_CONSOLE
770 /*
771  * Write a string to the 3215 console
772  */
773 static void
774 con3215_write(struct console *co, const char *str, unsigned int count)
775 {
776         struct raw3215_info *raw;
777         int i;
778
779         if (count <= 0)
780                 return;
781         raw = raw3215[0];       /* console 3215 is the first one */
782         while (count > 0) {
783                 for (i = 0; i < count; i++)
784                         if (str[i] == '\t' || str[i] == '\n')
785                                 break;
786                 raw3215_write(raw, str, i);
787                 count -= i;
788                 str += i;
789                 if (count > 0) {
790                         raw3215_putchar(raw, *str);
791                         count--;
792                         str++;
793                 }
794         }
795 }
796
797 static struct tty_driver *con3215_device(struct console *c, int *index)
798 {
799         *index = c->index;
800         return tty3215_driver;
801 }
802
803 /*
804  * panic() calls console_unblank before the system enters a
805  * disabled, endless loop.
806  */
807 static void
808 con3215_unblank(void)
809 {
810         struct raw3215_info *raw;
811         unsigned long flags;
812
813         raw = raw3215[0];  /* console 3215 is the first one */
814         spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags);
815         raw3215_make_room(raw, RAW3215_BUFFER_SIZE);
816         spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags);
817 }
818
819 /*
820  *  The console structure for the 3215 console
821  */
822 static struct console con3215 = {
823         .name    = "ttyS",
824         .write   = con3215_write,
825         .device  = con3215_device,
826         .unblank = con3215_unblank,
827         .flags   = CON_PRINTBUFFER,
828 };
829
830 /*
831  * 3215 console initialization code called from console_init().
832  * NOTE: This is called before kmalloc is available.
833  */
834 static int __init
835 con3215_init(void)
836 {
837         struct ccw_device *cdev;
838         struct raw3215_info *raw;
839         struct raw3215_req *req;
840         int i;
841
842         /* Check if 3215 is to be the console */
843         if (!CONSOLE_IS_3215)
844                 return -ENODEV;
845
846         /* Set the console mode for VM */
847         if (MACHINE_IS_VM) {
848                 cpcmd("TERM CONMODE 3215", NULL, 0, NULL);
849                 cpcmd("TERM AUTOCR OFF", NULL, 0, NULL);
850         }
851
852         /* allocate 3215 request structures */
853         raw3215_freelist = NULL;
854         spin_lock_init(&raw3215_freelist_lock);
855         for (i = 0; i < NR_3215_REQ; i++) {
856                 req = (struct raw3215_req *) alloc_bootmem_low(sizeof(struct raw3215_req));
857                 req->next = raw3215_freelist;
858                 raw3215_freelist = req;
859         }
860
861         cdev = ccw_device_probe_console();
862         if (IS_ERR(cdev))
863                 return -ENODEV;
864
865         raw3215[0] = raw = (struct raw3215_info *)
866                 alloc_bootmem_low(sizeof(struct raw3215_info));
867         memset(raw, 0, sizeof(struct raw3215_info));
868         raw->buffer = (char *) alloc_bootmem_low(RAW3215_BUFFER_SIZE);
869         raw->inbuf = (char *) alloc_bootmem_low(RAW3215_INBUF_SIZE);
870         raw->cdev = cdev;
871         cdev->dev.driver_data = raw;
872         cdev->handler = raw3215_irq;
873
874         raw->flags |= RAW3215_FIXED;
875         tasklet_init(&raw->tasklet,
876                      (void (*)(unsigned long)) raw3215_tasklet,
877                      (unsigned long) raw);
878         init_waitqueue_head(&raw->empty_wait);
879
880         /* Request the console irq */
881         if (raw3215_startup(raw) != 0) {
882                 free_bootmem((unsigned long) raw->inbuf, RAW3215_INBUF_SIZE);
883                 free_bootmem((unsigned long) raw->buffer, RAW3215_BUFFER_SIZE);
884                 free_bootmem((unsigned long) raw, sizeof(struct raw3215_info));
885                 raw3215[0] = NULL;
886                 printk("Couldn't find a 3215 console device\n");
887                 return -ENODEV;
888         }
889         register_console(&con3215);
890         return 0;
891 }
892 console_initcall(con3215_init);
893 #endif
894
895 /*
896  * tty3215_open
897  *
898  * This routine is called whenever a 3215 tty is opened.
899  */
900 static int
901 tty3215_open(struct tty_struct *tty, struct file * filp)
902 {
903         struct raw3215_info *raw;
904         int retval, line;
905
906         line = tty->index;
907         if ((line < 0) || (line >= NR_3215))
908                 return -ENODEV;
909
910         raw = raw3215[line];
911         if (raw == NULL)
912                 return -ENODEV;
913
914         tty->driver_data = raw;
915         raw->tty = tty;
916
917         tty->low_latency = 0;  /* don't use bottom half for pushing chars */
918         /*
919          * Start up 3215 device
920          */
921         retval = raw3215_startup(raw);
922         if (retval)
923                 return retval;
924
925         return 0;
926 }
927
928 /*
929  * tty3215_close()
930  *
931  * This routine is called when the 3215 tty is closed. We wait
932  * for the remaining request to be completed. Then we clean up.
933  */
934 static void
935 tty3215_close(struct tty_struct *tty, struct file * filp)
936 {
937         struct raw3215_info *raw;
938
939         raw = (struct raw3215_info *) tty->driver_data;
940         if (raw == NULL || tty->count > 1)
941                 return;
942         tty->closing = 1;
943         /* Shutdown the terminal */
944         raw3215_shutdown(raw);
945         tty->closing = 0;
946         raw->tty = NULL;
947 }
948
949 /*
950  * Returns the amount of free space in the output buffer.
951  */
952 static int
953 tty3215_write_room(struct tty_struct *tty)
954 {
955         struct raw3215_info *raw;
956
957         raw = (struct raw3215_info *) tty->driver_data;
958
959         /* Subtract TAB_STOP_SIZE to allow for a tab, 8 <<< 64K */
960         if ((RAW3215_BUFFER_SIZE - raw->count - TAB_STOP_SIZE) >= 0)
961                 return RAW3215_BUFFER_SIZE - raw->count - TAB_STOP_SIZE;
962         else
963                 return 0;
964 }
965
966 /*
967  * String write routine for 3215 ttys
968  */
969 static int
970 tty3215_write(struct tty_struct * tty,
971               const unsigned char *buf, int count)
972 {
973         struct raw3215_info *raw;
974
975         if (!tty)
976                 return 0;
977         raw = (struct raw3215_info *) tty->driver_data;
978         raw3215_write(raw, buf, count);
979         return count;
980 }
981
982 /*
983  * Put character routine for 3215 ttys
984  */
985 static int
986 tty3215_put_char(struct tty_struct *tty, unsigned char ch)
987 {
988         struct raw3215_info *raw;
989
990         if (!tty)
991                 return 0;
992         raw = (struct raw3215_info *) tty->driver_data;
993         raw3215_putchar(raw, ch);
994         return 1;
995 }
996
997 static void
998 tty3215_flush_chars(struct tty_struct *tty)
999 {
1000 }
1001
1002 /*
1003  * Returns the number of characters in the output buffer
1004  */
1005 static int
1006 tty3215_chars_in_buffer(struct tty_struct *tty)
1007 {
1008         struct raw3215_info *raw;
1009
1010         raw = (struct raw3215_info *) tty->driver_data;
1011         return raw->count;
1012 }
1013
1014 static void
1015 tty3215_flush_buffer(struct tty_struct *tty)
1016 {
1017         struct raw3215_info *raw;
1018
1019         raw = (struct raw3215_info *) tty->driver_data;
1020         raw3215_flush_buffer(raw);
1021         tty_wakeup(tty);
1022 }
1023
1024 /*
1025  * Currently we don't have any io controls for 3215 ttys
1026  */
1027 static int
1028 tty3215_ioctl(struct tty_struct *tty, struct file * file,
1029               unsigned int cmd, unsigned long arg)
1030 {
1031         if (tty->flags & (1 << TTY_IO_ERROR))
1032                 return -EIO;
1033
1034         switch (cmd) {
1035         default:
1036                 return -ENOIOCTLCMD;
1037         }
1038         return 0;
1039 }
1040
1041 /*
1042  * Disable reading from a 3215 tty
1043  */
1044 static void
1045 tty3215_throttle(struct tty_struct * tty)
1046 {
1047         struct raw3215_info *raw;
1048
1049         raw = (struct raw3215_info *) tty->driver_data;
1050         raw->flags |= RAW3215_THROTTLED;
1051 }
1052
1053 /*
1054  * Enable reading from a 3215 tty
1055  */
1056 static void
1057 tty3215_unthrottle(struct tty_struct * tty)
1058 {
1059         struct raw3215_info *raw;
1060         unsigned long flags;
1061
1062         raw = (struct raw3215_info *) tty->driver_data;
1063         if (raw->flags & RAW3215_THROTTLED) {
1064                 spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags);
1065                 raw->flags &= ~RAW3215_THROTTLED;
1066                 raw3215_try_io(raw);
1067                 spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags);
1068         }
1069 }
1070
1071 /*
1072  * Disable writing to a 3215 tty
1073  */
1074 static void
1075 tty3215_stop(struct tty_struct *tty)
1076 {
1077         struct raw3215_info *raw;
1078
1079         raw = (struct raw3215_info *) tty->driver_data;
1080         raw->flags |= RAW3215_STOPPED;
1081 }
1082
1083 /*
1084  * Enable writing to a 3215 tty
1085  */
1086 static void
1087 tty3215_start(struct tty_struct *tty)
1088 {
1089         struct raw3215_info *raw;
1090         unsigned long flags;
1091
1092         raw = (struct raw3215_info *) tty->driver_data;
1093         if (raw->flags & RAW3215_STOPPED) {
1094                 spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags);
1095                 raw->flags &= ~RAW3215_STOPPED;
1096                 raw3215_try_io(raw);
1097                 spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags);
1098         }
1099 }
1100
1101 static const struct tty_operations tty3215_ops = {
1102         .open = tty3215_open,
1103         .close = tty3215_close,
1104         .write = tty3215_write,
1105         .put_char = tty3215_put_char,
1106         .flush_chars = tty3215_flush_chars,
1107         .write_room = tty3215_write_room,
1108         .chars_in_buffer = tty3215_chars_in_buffer,
1109         .flush_buffer = tty3215_flush_buffer,
1110         .ioctl = tty3215_ioctl,
1111         .throttle = tty3215_throttle,
1112         .unthrottle = tty3215_unthrottle,
1113         .stop = tty3215_stop,
1114         .start = tty3215_start,
1115 };
1116
1117 /*
1118  * 3215 tty registration code called from tty_init().
1119  * Most kernel services (incl. kmalloc) are available at this poimt.
1120  */
1121 static int __init
1122 tty3215_init(void)
1123 {
1124         struct tty_driver *driver;
1125         int ret;
1126
1127         if (!CONSOLE_IS_3215)
1128                 return 0;
1129
1130         driver = alloc_tty_driver(NR_3215);
1131         if (!driver)
1132                 return -ENOMEM;
1133
1134         ret = ccw_driver_register(&raw3215_ccw_driver);
1135         if (ret) {
1136                 put_tty_driver(driver);
1137                 return ret;
1138         }
1139         /*
1140          * Initialize the tty_driver structure
1141          * Entries in tty3215_driver that are NOT initialized:
1142          * proc_entry, set_termios, flush_buffer, set_ldisc, write_proc
1143          */
1144
1145         driver->owner = THIS_MODULE;
1146         driver->driver_name = "tty3215";
1147         driver->name = "ttyS";
1148         driver->major = TTY_MAJOR;
1149         driver->minor_start = 64;
1150         driver->type = TTY_DRIVER_TYPE_SYSTEM;
1151         driver->subtype = SYSTEM_TYPE_TTY;
1152         driver->init_termios = tty_std_termios;
1153         driver->init_termios.c_iflag = IGNBRK | IGNPAR;
1154         driver->init_termios.c_oflag = ONLCR | XTABS;
1155         driver->init_termios.c_lflag = ISIG;
1156         driver->flags = TTY_DRIVER_REAL_RAW;
1157         tty_set_operations(driver, &tty3215_ops);
1158         ret = tty_register_driver(driver);
1159         if (ret) {
1160                 printk("Couldn't register tty3215 driver\n");
1161                 put_tty_driver(driver);
1162                 return ret;
1163         }
1164         tty3215_driver = driver;
1165         return 0;
1166 }
1167
1168 static void __exit
1169 tty3215_exit(void)
1170 {
1171         tty_unregister_driver(tty3215_driver);
1172         put_tty_driver(tty3215_driver);
1173         ccw_driver_unregister(&raw3215_ccw_driver);
1174 }
1175
1176 module_init(tty3215_init);
1177 module_exit(tty3215_exit);