[PATCH] aic7xxx_osm build fix
[cris-mirror.git] / drivers / s390 / char / sclp_tty.c
bloba20d7c89341dabf3d36d07024eb7d78e8b656cd4
1 /*
2 * drivers/s390/char/sclp_tty.c
3 * SCLP line mode terminal driver.
5 * S390 version
6 * Copyright (C) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation
7 * Author(s): Martin Peschke <mpeschke@de.ibm.com>
8 * Martin Schwidefsky <schwidefsky@de.ibm.com>
9 */
11 #include <linux/config.h>
12 #include <linux/module.h>
13 #include <linux/kmod.h>
14 #include <linux/tty.h>
15 #include <linux/tty_driver.h>
16 #include <linux/sched.h>
17 #include <linux/wait.h>
18 #include <linux/slab.h>
19 #include <linux/err.h>
20 #include <linux/init.h>
21 #include <linux/interrupt.h>
22 #include <asm/uaccess.h>
24 #include "ctrlchar.h"
25 #include "sclp.h"
26 #include "sclp_rw.h"
27 #include "sclp_tty.h"
29 #define SCLP_TTY_PRINT_HEADER "sclp tty driver: "
32 * size of a buffer that collects single characters coming in
33 * via sclp_tty_put_char()
35 #define SCLP_TTY_BUF_SIZE 512
38 * There is exactly one SCLP terminal, so we can keep things simple
39 * and allocate all variables statically.
42 /* Lock to guard over changes to global variables. */
43 static spinlock_t sclp_tty_lock;
44 /* List of free pages that can be used for console output buffering. */
45 static struct list_head sclp_tty_pages;
46 /* List of full struct sclp_buffer structures ready for output. */
47 static struct list_head sclp_tty_outqueue;
48 /* Counter how many buffers are emitted. */
49 static int sclp_tty_buffer_count;
50 /* Pointer to current console buffer. */
51 static struct sclp_buffer *sclp_ttybuf;
52 /* Timer for delayed output of console messages. */
53 static struct timer_list sclp_tty_timer;
54 /* Waitqueue to wait for buffers to get empty. */
55 static wait_queue_head_t sclp_tty_waitq;
57 static struct tty_struct *sclp_tty;
58 static unsigned char sclp_tty_chars[SCLP_TTY_BUF_SIZE];
59 static unsigned short int sclp_tty_chars_count;
61 struct tty_driver *sclp_tty_driver;
63 extern struct termios tty_std_termios;
65 static struct sclp_ioctls sclp_ioctls;
66 static struct sclp_ioctls sclp_ioctls_init =
68 8, /* 1 hor. tab. = 8 spaces */
69 0, /* no echo of input by this driver */
70 80, /* 80 characters/line */
71 1, /* write after 1/10 s without final new line */
72 MAX_KMEM_PAGES, /* quick fix: avoid __alloc_pages */
73 MAX_KMEM_PAGES, /* take 32/64 pages from kernel memory, */
74 0, /* do not convert to lower case */
75 0x6c /* to seprate upper and lower case */
76 /* ('%' in EBCDIC) */
79 /* This routine is called whenever we try to open a SCLP terminal. */
80 static int
81 sclp_tty_open(struct tty_struct *tty, struct file *filp)
83 sclp_tty = tty;
84 tty->driver_data = NULL;
85 tty->low_latency = 0;
86 return 0;
89 /* This routine is called when the SCLP terminal is closed. */
90 static void
91 sclp_tty_close(struct tty_struct *tty, struct file *filp)
93 if (tty->count > 1)
94 return;
95 sclp_tty = NULL;
98 /* execute commands to control the i/o behaviour of the SCLP tty at runtime */
99 static int
100 sclp_tty_ioctl(struct tty_struct *tty, struct file * file,
101 unsigned int cmd, unsigned long arg)
103 unsigned long flags;
104 unsigned int obuf;
105 int check;
106 int rc;
108 if (tty->flags & (1 << TTY_IO_ERROR))
109 return -EIO;
110 rc = 0;
111 check = 0;
112 switch (cmd) {
113 case TIOCSCLPSHTAB:
114 /* set width of horizontal tab */
115 if (get_user(sclp_ioctls.htab, (unsigned short __user *) arg))
116 rc = -EFAULT;
117 else
118 check = 1;
119 break;
120 case TIOCSCLPGHTAB:
121 /* get width of horizontal tab */
122 if (put_user(sclp_ioctls.htab, (unsigned short __user *) arg))
123 rc = -EFAULT;
124 break;
125 case TIOCSCLPSECHO:
126 /* enable/disable echo of input */
127 if (get_user(sclp_ioctls.echo, (unsigned char __user *) arg))
128 rc = -EFAULT;
129 break;
130 case TIOCSCLPGECHO:
131 /* Is echo of input enabled ? */
132 if (put_user(sclp_ioctls.echo, (unsigned char __user *) arg))
133 rc = -EFAULT;
134 break;
135 case TIOCSCLPSCOLS:
136 /* set number of columns for output */
137 if (get_user(sclp_ioctls.columns, (unsigned short __user *) arg))
138 rc = -EFAULT;
139 else
140 check = 1;
141 break;
142 case TIOCSCLPGCOLS:
143 /* get number of columns for output */
144 if (put_user(sclp_ioctls.columns, (unsigned short __user *) arg))
145 rc = -EFAULT;
146 break;
147 case TIOCSCLPSNL:
148 /* enable/disable writing without final new line character */
149 if (get_user(sclp_ioctls.final_nl, (signed char __user *) arg))
150 rc = -EFAULT;
151 break;
152 case TIOCSCLPGNL:
153 /* Is writing without final new line character enabled ? */
154 if (put_user(sclp_ioctls.final_nl, (signed char __user *) arg))
155 rc = -EFAULT;
156 break;
157 case TIOCSCLPSOBUF:
159 * set the maximum buffers size for output, will be rounded
160 * up to next 4kB boundary and stored as number of SCCBs
161 * (4kB Buffers) limitation: 256 x 4kB
163 if (get_user(obuf, (unsigned int __user *) arg) == 0) {
164 if (obuf & 0xFFF)
165 sclp_ioctls.max_sccb = (obuf >> 12) + 1;
166 else
167 sclp_ioctls.max_sccb = (obuf >> 12);
168 } else
169 rc = -EFAULT;
170 break;
171 case TIOCSCLPGOBUF:
172 /* get the maximum buffers size for output */
173 obuf = sclp_ioctls.max_sccb << 12;
174 if (put_user(obuf, (unsigned int __user *) arg))
175 rc = -EFAULT;
176 break;
177 case TIOCSCLPGKBUF:
178 /* get the number of buffers got from kernel at startup */
179 if (put_user(sclp_ioctls.kmem_sccb, (unsigned short __user *) arg))
180 rc = -EFAULT;
181 break;
182 case TIOCSCLPSCASE:
183 /* enable/disable conversion from upper to lower case */
184 if (get_user(sclp_ioctls.tolower, (unsigned char __user *) arg))
185 rc = -EFAULT;
186 break;
187 case TIOCSCLPGCASE:
188 /* Is conversion from upper to lower case of input enabled? */
189 if (put_user(sclp_ioctls.tolower, (unsigned char __user *) arg))
190 rc = -EFAULT;
191 break;
192 case TIOCSCLPSDELIM:
194 * set special character used for separating upper and
195 * lower case, 0x00 disables this feature
197 if (get_user(sclp_ioctls.delim, (unsigned char __user *) arg))
198 rc = -EFAULT;
199 break;
200 case TIOCSCLPGDELIM:
202 * get special character used for separating upper and
203 * lower case, 0x00 disables this feature
205 if (put_user(sclp_ioctls.delim, (unsigned char __user *) arg))
206 rc = -EFAULT;
207 break;
208 case TIOCSCLPSINIT:
209 /* set initial (default) sclp ioctls */
210 sclp_ioctls = sclp_ioctls_init;
211 check = 1;
212 break;
213 default:
214 rc = -ENOIOCTLCMD;
215 break;
217 if (check) {
218 spin_lock_irqsave(&sclp_tty_lock, flags);
219 if (sclp_ttybuf != NULL) {
220 sclp_set_htab(sclp_ttybuf, sclp_ioctls.htab);
221 sclp_set_columns(sclp_ttybuf, sclp_ioctls.columns);
223 spin_unlock_irqrestore(&sclp_tty_lock, flags);
225 return rc;
229 * This routine returns the numbers of characters the tty driver
230 * will accept for queuing to be written. This number is subject
231 * to change as output buffers get emptied, or if the output flow
232 * control is acted. This is not an exact number because not every
233 * character needs the same space in the sccb. The worst case is
234 * a string of newlines. Every newlines creates a new mto which
235 * needs 8 bytes.
237 static int
238 sclp_tty_write_room (struct tty_struct *tty)
240 unsigned long flags;
241 struct list_head *l;
242 int count;
244 spin_lock_irqsave(&sclp_tty_lock, flags);
245 count = 0;
246 if (sclp_ttybuf != NULL)
247 count = sclp_buffer_space(sclp_ttybuf) / sizeof(struct mto);
248 list_for_each(l, &sclp_tty_pages)
249 count += NR_EMPTY_MTO_PER_SCCB;
250 spin_unlock_irqrestore(&sclp_tty_lock, flags);
251 return count;
254 static void
255 sclp_ttybuf_callback(struct sclp_buffer *buffer, int rc)
257 unsigned long flags;
258 void *page;
260 do {
261 page = sclp_unmake_buffer(buffer);
262 spin_lock_irqsave(&sclp_tty_lock, flags);
263 /* Remove buffer from outqueue */
264 list_del(&buffer->list);
265 sclp_tty_buffer_count--;
266 list_add_tail((struct list_head *) page, &sclp_tty_pages);
267 /* Check if there is a pending buffer on the out queue. */
268 buffer = NULL;
269 if (!list_empty(&sclp_tty_outqueue))
270 buffer = list_entry(sclp_tty_outqueue.next,
271 struct sclp_buffer, list);
272 spin_unlock_irqrestore(&sclp_tty_lock, flags);
273 } while (buffer && sclp_emit_buffer(buffer, sclp_ttybuf_callback));
274 wake_up(&sclp_tty_waitq);
275 /* check if the tty needs a wake up call */
276 if (sclp_tty != NULL) {
277 tty_wakeup(sclp_tty);
281 static inline void
282 __sclp_ttybuf_emit(struct sclp_buffer *buffer)
284 unsigned long flags;
285 int count;
286 int rc;
288 spin_lock_irqsave(&sclp_tty_lock, flags);
289 list_add_tail(&buffer->list, &sclp_tty_outqueue);
290 count = sclp_tty_buffer_count++;
291 spin_unlock_irqrestore(&sclp_tty_lock, flags);
292 if (count)
293 return;
294 rc = sclp_emit_buffer(buffer, sclp_ttybuf_callback);
295 if (rc)
296 sclp_ttybuf_callback(buffer, rc);
300 * When this routine is called from the timer then we flush the
301 * temporary write buffer.
303 static void
304 sclp_tty_timeout(unsigned long data)
306 unsigned long flags;
307 struct sclp_buffer *buf;
309 spin_lock_irqsave(&sclp_tty_lock, flags);
310 buf = sclp_ttybuf;
311 sclp_ttybuf = NULL;
312 spin_unlock_irqrestore(&sclp_tty_lock, flags);
314 if (buf != NULL) {
315 __sclp_ttybuf_emit(buf);
320 * Write a string to the sclp tty.
322 static void
323 sclp_tty_write_string(const unsigned char *str, int count)
325 unsigned long flags;
326 void *page;
327 int written;
328 struct sclp_buffer *buf;
330 if (count <= 0)
331 return;
332 spin_lock_irqsave(&sclp_tty_lock, flags);
333 do {
334 /* Create a sclp output buffer if none exists yet */
335 if (sclp_ttybuf == NULL) {
336 while (list_empty(&sclp_tty_pages)) {
337 spin_unlock_irqrestore(&sclp_tty_lock, flags);
338 if (in_interrupt())
339 sclp_sync_wait();
340 else
341 wait_event(sclp_tty_waitq,
342 !list_empty(&sclp_tty_pages));
343 spin_lock_irqsave(&sclp_tty_lock, flags);
345 page = sclp_tty_pages.next;
346 list_del((struct list_head *) page);
347 sclp_ttybuf = sclp_make_buffer(page,
348 sclp_ioctls.columns,
349 sclp_ioctls.htab);
351 /* try to write the string to the current output buffer */
352 written = sclp_write(sclp_ttybuf, str, count);
353 if (written == count)
354 break;
356 * Not all characters could be written to the current
357 * output buffer. Emit the buffer, create a new buffer
358 * and then output the rest of the string.
360 buf = sclp_ttybuf;
361 sclp_ttybuf = NULL;
362 spin_unlock_irqrestore(&sclp_tty_lock, flags);
363 __sclp_ttybuf_emit(buf);
364 spin_lock_irqsave(&sclp_tty_lock, flags);
365 str += written;
366 count -= written;
367 } while (count > 0);
368 /* Setup timer to output current console buffer after 1/10 second */
369 if (sclp_ioctls.final_nl) {
370 if (sclp_ttybuf != NULL &&
371 sclp_chars_in_buffer(sclp_ttybuf) != 0 &&
372 !timer_pending(&sclp_tty_timer)) {
373 init_timer(&sclp_tty_timer);
374 sclp_tty_timer.function = sclp_tty_timeout;
375 sclp_tty_timer.data = 0UL;
376 sclp_tty_timer.expires = jiffies + HZ/10;
377 add_timer(&sclp_tty_timer);
379 } else {
380 if (sclp_ttybuf != NULL &&
381 sclp_chars_in_buffer(sclp_ttybuf) != 0) {
382 buf = sclp_ttybuf;
383 sclp_ttybuf = NULL;
384 spin_unlock_irqrestore(&sclp_tty_lock, flags);
385 __sclp_ttybuf_emit(buf);
386 spin_lock_irqsave(&sclp_tty_lock, flags);
389 spin_unlock_irqrestore(&sclp_tty_lock, flags);
393 * This routine is called by the kernel to write a series of characters to the
394 * tty device. The characters may come from user space or kernel space. This
395 * routine will return the number of characters actually accepted for writing.
397 static int
398 sclp_tty_write(struct tty_struct *tty, const unsigned char *buf, int count)
400 if (sclp_tty_chars_count > 0) {
401 sclp_tty_write_string(sclp_tty_chars, sclp_tty_chars_count);
402 sclp_tty_chars_count = 0;
404 sclp_tty_write_string(buf, count);
405 return count;
409 * This routine is called by the kernel to write a single character to the tty
410 * device. If the kernel uses this routine, it must call the flush_chars()
411 * routine (if defined) when it is done stuffing characters into the driver.
413 * Characters provided to sclp_tty_put_char() are buffered by the SCLP driver.
414 * If the given character is a '\n' the contents of the SCLP write buffer
415 * - including previous characters from sclp_tty_put_char() and strings from
416 * sclp_write() without final '\n' - will be written.
418 static void
419 sclp_tty_put_char(struct tty_struct *tty, unsigned char ch)
421 sclp_tty_chars[sclp_tty_chars_count++] = ch;
422 if (ch == '\n' || sclp_tty_chars_count >= SCLP_TTY_BUF_SIZE) {
423 sclp_tty_write_string(sclp_tty_chars, sclp_tty_chars_count);
424 sclp_tty_chars_count = 0;
429 * This routine is called by the kernel after it has written a series of
430 * characters to the tty device using put_char().
432 static void
433 sclp_tty_flush_chars(struct tty_struct *tty)
435 if (sclp_tty_chars_count > 0) {
436 sclp_tty_write_string(sclp_tty_chars, sclp_tty_chars_count);
437 sclp_tty_chars_count = 0;
442 * This routine returns the number of characters in the write buffer of the
443 * SCLP driver. The provided number includes all characters that are stored
444 * in the SCCB (will be written next time the SCLP is not busy) as well as
445 * characters in the write buffer (will not be written as long as there is a
446 * final line feed missing).
448 static int
449 sclp_tty_chars_in_buffer(struct tty_struct *tty)
451 unsigned long flags;
452 struct list_head *l;
453 struct sclp_buffer *t;
454 int count;
456 spin_lock_irqsave(&sclp_tty_lock, flags);
457 count = 0;
458 if (sclp_ttybuf != NULL)
459 count = sclp_chars_in_buffer(sclp_ttybuf);
460 list_for_each(l, &sclp_tty_outqueue) {
461 t = list_entry(l, struct sclp_buffer, list);
462 count += sclp_chars_in_buffer(t);
464 spin_unlock_irqrestore(&sclp_tty_lock, flags);
465 return count;
469 * removes all content from buffers of low level driver
471 static void
472 sclp_tty_flush_buffer(struct tty_struct *tty)
474 if (sclp_tty_chars_count > 0) {
475 sclp_tty_write_string(sclp_tty_chars, sclp_tty_chars_count);
476 sclp_tty_chars_count = 0;
481 * push input to tty
483 static void
484 sclp_tty_input(unsigned char* buf, unsigned int count)
486 unsigned int cchar;
489 * If this tty driver is currently closed
490 * then throw the received input away.
492 if (sclp_tty == NULL)
493 return;
494 cchar = ctrlchar_handle(buf, count, sclp_tty);
495 switch (cchar & CTRLCHAR_MASK) {
496 case CTRLCHAR_SYSRQ:
497 break;
498 case CTRLCHAR_CTRL:
499 sclp_tty->flip.count++;
500 *sclp_tty->flip.flag_buf_ptr++ = TTY_NORMAL;
501 *sclp_tty->flip.char_buf_ptr++ = cchar;
502 tty_flip_buffer_push(sclp_tty);
503 break;
504 case CTRLCHAR_NONE:
505 /* send (normal) input to line discipline */
506 memcpy(sclp_tty->flip.char_buf_ptr, buf, count);
507 if (count < 2 ||
508 (strncmp ((const char *) buf + count - 2, "^n", 2) &&
509 strncmp ((const char *) buf + count - 2, "\0252n", 2))) {
510 sclp_tty->flip.char_buf_ptr[count] = '\n';
511 count++;
512 } else
513 count -= 2;
514 memset(sclp_tty->flip.flag_buf_ptr, TTY_NORMAL, count);
515 sclp_tty->flip.char_buf_ptr += count;
516 sclp_tty->flip.flag_buf_ptr += count;
517 sclp_tty->flip.count += count;
518 tty_flip_buffer_push(sclp_tty);
519 break;
524 * get a EBCDIC string in upper/lower case,
525 * find out characters in lower/upper case separated by a special character,
526 * modifiy original string,
527 * returns length of resulting string
529 static int
530 sclp_switch_cases(unsigned char *buf, int count,
531 unsigned char delim, int tolower)
533 unsigned char *ip, *op;
534 int toggle;
536 /* initially changing case is off */
537 toggle = 0;
538 ip = op = buf;
539 while (count-- > 0) {
540 /* compare with special character */
541 if (*ip == delim) {
542 /* followed by another special character? */
543 if (count && ip[1] == delim) {
545 * ... then put a single copy of the special
546 * character to the output string
548 *op++ = *ip++;
549 count--;
550 } else
552 * ... special character follower by a normal
553 * character toggles the case change behaviour
555 toggle = ~toggle;
556 /* skip special character */
557 ip++;
558 } else
559 /* not the special character */
560 if (toggle)
561 /* but case switching is on */
562 if (tolower)
563 /* switch to uppercase */
564 *op++ = _ebc_toupper[(int) *ip++];
565 else
566 /* switch to lowercase */
567 *op++ = _ebc_tolower[(int) *ip++];
568 else
569 /* no case switching, copy the character */
570 *op++ = *ip++;
572 /* return length of reformatted string. */
573 return op - buf;
576 static void
577 sclp_get_input(unsigned char *start, unsigned char *end)
579 int count;
581 count = end - start;
583 * if set in ioctl convert EBCDIC to lower case
584 * (modify original input in SCCB)
586 if (sclp_ioctls.tolower)
587 EBC_TOLOWER(start, count);
590 * if set in ioctl find out characters in lower or upper case
591 * (depends on current case) separated by a special character,
592 * works on EBCDIC
594 if (sclp_ioctls.delim)
595 count = sclp_switch_cases(start, count,
596 sclp_ioctls.delim,
597 sclp_ioctls.tolower);
599 /* convert EBCDIC to ASCII (modify original input in SCCB) */
600 sclp_ebcasc_str(start, count);
602 /* if set in ioctl write operators input to console */
603 if (sclp_ioctls.echo)
604 sclp_tty_write(sclp_tty, start, count);
606 /* transfer input to high level driver */
607 sclp_tty_input(start, count);
610 static inline struct gds_vector *
611 find_gds_vector(struct gds_vector *start, struct gds_vector *end, u16 id)
613 struct gds_vector *vec;
615 for (vec = start; vec < end; vec = (void *) vec + vec->length)
616 if (vec->gds_id == id)
617 return vec;
618 return NULL;
621 static inline struct gds_subvector *
622 find_gds_subvector(struct gds_subvector *start,
623 struct gds_subvector *end, u8 key)
625 struct gds_subvector *subvec;
627 for (subvec = start; subvec < end;
628 subvec = (void *) subvec + subvec->length)
629 if (subvec->key == key)
630 return subvec;
631 return NULL;
634 static inline void
635 sclp_eval_selfdeftextmsg(struct gds_subvector *start,
636 struct gds_subvector *end)
638 struct gds_subvector *subvec;
640 subvec = start;
641 while (subvec < end) {
642 subvec = find_gds_subvector(subvec, end, 0x30);
643 if (!subvec)
644 break;
645 sclp_get_input((unsigned char *)(subvec + 1),
646 (unsigned char *) subvec + subvec->length);
647 subvec = (void *) subvec + subvec->length;
651 static inline void
652 sclp_eval_textcmd(struct gds_subvector *start,
653 struct gds_subvector *end)
655 struct gds_subvector *subvec;
657 subvec = start;
658 while (subvec < end) {
659 subvec = find_gds_subvector(subvec, end,
660 GDS_KEY_SelfDefTextMsg);
661 if (!subvec)
662 break;
663 sclp_eval_selfdeftextmsg((struct gds_subvector *)(subvec + 1),
664 (void *)subvec + subvec->length);
665 subvec = (void *) subvec + subvec->length;
669 static inline void
670 sclp_eval_cpmsu(struct gds_vector *start, struct gds_vector *end)
672 struct gds_vector *vec;
674 vec = start;
675 while (vec < end) {
676 vec = find_gds_vector(vec, end, GDS_ID_TextCmd);
677 if (!vec)
678 break;
679 sclp_eval_textcmd((struct gds_subvector *)(vec + 1),
680 (void *) vec + vec->length);
681 vec = (void *) vec + vec->length;
686 static inline void
687 sclp_eval_mdsmu(struct gds_vector *start, void *end)
689 struct gds_vector *vec;
691 vec = find_gds_vector(start, end, GDS_ID_CPMSU);
692 if (vec)
693 sclp_eval_cpmsu(vec + 1, (void *) vec + vec->length);
696 static void
697 sclp_tty_receiver(struct evbuf_header *evbuf)
699 struct gds_vector *start, *end, *vec;
701 start = (struct gds_vector *)(evbuf + 1);
702 end = (void *) evbuf + evbuf->length;
703 vec = find_gds_vector(start, end, GDS_ID_MDSMU);
704 if (vec)
705 sclp_eval_mdsmu(vec + 1, (void *) vec + vec->length);
708 static void
709 sclp_tty_state_change(struct sclp_register *reg)
713 static struct sclp_register sclp_input_event =
715 .receive_mask = EvTyp_OpCmd_Mask | EvTyp_PMsgCmd_Mask,
716 .state_change_fn = sclp_tty_state_change,
717 .receiver_fn = sclp_tty_receiver
720 static struct tty_operations sclp_ops = {
721 .open = sclp_tty_open,
722 .close = sclp_tty_close,
723 .write = sclp_tty_write,
724 .put_char = sclp_tty_put_char,
725 .flush_chars = sclp_tty_flush_chars,
726 .write_room = sclp_tty_write_room,
727 .chars_in_buffer = sclp_tty_chars_in_buffer,
728 .flush_buffer = sclp_tty_flush_buffer,
729 .ioctl = sclp_tty_ioctl,
732 int __init
733 sclp_tty_init(void)
735 struct tty_driver *driver;
736 void *page;
737 int i;
738 int rc;
740 if (!CONSOLE_IS_SCLP)
741 return 0;
742 driver = alloc_tty_driver(1);
743 if (!driver)
744 return -ENOMEM;
746 rc = sclp_rw_init();
747 if (rc) {
748 printk(KERN_ERR SCLP_TTY_PRINT_HEADER
749 "could not register tty - "
750 "sclp_rw_init returned %d\n", rc);
751 put_tty_driver(driver);
752 return rc;
754 /* Allocate pages for output buffering */
755 INIT_LIST_HEAD(&sclp_tty_pages);
756 for (i = 0; i < MAX_KMEM_PAGES; i++) {
757 page = (void *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
758 if (page == NULL) {
759 put_tty_driver(driver);
760 return -ENOMEM;
762 list_add_tail((struct list_head *) page, &sclp_tty_pages);
764 INIT_LIST_HEAD(&sclp_tty_outqueue);
765 spin_lock_init(&sclp_tty_lock);
766 init_waitqueue_head(&sclp_tty_waitq);
767 init_timer(&sclp_tty_timer);
768 sclp_ttybuf = NULL;
769 sclp_tty_buffer_count = 0;
770 if (MACHINE_IS_VM) {
772 * save 4 characters for the CPU number
773 * written at start of each line by VM/CP
775 sclp_ioctls_init.columns = 76;
776 /* case input lines to lowercase */
777 sclp_ioctls_init.tolower = 1;
779 sclp_ioctls = sclp_ioctls_init;
780 sclp_tty_chars_count = 0;
781 sclp_tty = NULL;
783 rc = sclp_register(&sclp_input_event);
784 if (rc) {
785 put_tty_driver(driver);
786 return rc;
789 driver->owner = THIS_MODULE;
790 driver->driver_name = "sclp_line";
791 driver->name = "sclp_line";
792 driver->major = TTY_MAJOR;
793 driver->minor_start = 64;
794 driver->type = TTY_DRIVER_TYPE_SYSTEM;
795 driver->subtype = SYSTEM_TYPE_TTY;
796 driver->init_termios = tty_std_termios;
797 driver->init_termios.c_iflag = IGNBRK | IGNPAR;
798 driver->init_termios.c_oflag = ONLCR | XTABS;
799 driver->init_termios.c_lflag = ISIG | ECHO;
800 driver->flags = TTY_DRIVER_REAL_RAW;
801 tty_set_operations(driver, &sclp_ops);
802 rc = tty_register_driver(driver);
803 if (rc) {
804 printk(KERN_ERR SCLP_TTY_PRINT_HEADER
805 "could not register tty - "
806 "tty_register_driver returned %d\n", rc);
807 put_tty_driver(driver);
808 return rc;
810 sclp_tty_driver = driver;
811 return 0;
813 module_init(sclp_tty_init);