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1/*
2 * drivers/s390/char/sclp_tty.c
3 * SCLP line mode terminal driver.
4 *
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 */
10
11#include <linux/module.h>
12#include <linux/kmod.h>
13#include <linux/tty.h>
14#include <linux/tty_driver.h>
15#include <linux/tty_flip.h>
16#include <linux/err.h>
17#include <linux/init.h>
18#include <linux/interrupt.h>
19#include <linux/gfp.h>
20#include <asm/uaccess.h>
21
22#include "ctrlchar.h"
23#include "sclp.h"
24#include "sclp_rw.h"
25#include "sclp_tty.h"
26
27/*
28 * size of a buffer that collects single characters coming in
29 * via sclp_tty_put_char()
30 */
31#define SCLP_TTY_BUF_SIZE 512
32
33/*
34 * There is exactly one SCLP terminal, so we can keep things simple
35 * and allocate all variables statically.
36 */
37
38/* Lock to guard over changes to global variables. */
39static spinlock_t sclp_tty_lock;
40/* List of free pages that can be used for console output buffering. */
41static struct list_head sclp_tty_pages;
42/* List of full struct sclp_buffer structures ready for output. */
43static struct list_head sclp_tty_outqueue;
44/* Counter how many buffers are emitted. */
45static int sclp_tty_buffer_count;
46/* Pointer to current console buffer. */
47static struct sclp_buffer *sclp_ttybuf;
48/* Timer for delayed output of console messages. */
49static struct timer_list sclp_tty_timer;
50
51static struct tty_struct *sclp_tty;
52static unsigned char sclp_tty_chars[SCLP_TTY_BUF_SIZE];
53static unsigned short int sclp_tty_chars_count;
54
55struct tty_driver *sclp_tty_driver;
56
57static int sclp_tty_tolower;
58static int sclp_tty_columns = 80;
59
60#define SPACES_PER_TAB 8
61#define CASE_DELIMITER 0x6c /* to separate upper and lower case (% in EBCDIC) */
62
63/* This routine is called whenever we try to open a SCLP terminal. */
64static int
65sclp_tty_open(struct tty_struct *tty, struct file *filp)
66{
67 sclp_tty = tty;
68 tty->driver_data = NULL;
69 tty->low_latency = 0;
70 return 0;
71}
72
73/* This routine is called when the SCLP terminal is closed. */
74static void
75sclp_tty_close(struct tty_struct *tty, struct file *filp)
76{
77 if (tty->count > 1)
78 return;
79 sclp_tty = NULL;
80}
81
82/*
83 * This routine returns the numbers of characters the tty driver
84 * will accept for queuing to be written. This number is subject
85 * to change as output buffers get emptied, or if the output flow
86 * control is acted. This is not an exact number because not every
87 * character needs the same space in the sccb. The worst case is
88 * a string of newlines. Every newlines creates a new mto which
89 * needs 8 bytes.
90 */
91static int
92sclp_tty_write_room (struct tty_struct *tty)
93{
94 unsigned long flags;
95 struct list_head *l;
96 int count;
97
98 spin_lock_irqsave(&sclp_tty_lock, flags);
99 count = 0;
100 if (sclp_ttybuf != NULL)
101 count = sclp_buffer_space(sclp_ttybuf) / sizeof(struct mto);
102 list_for_each(l, &sclp_tty_pages)
103 count += NR_EMPTY_MTO_PER_SCCB;
104 spin_unlock_irqrestore(&sclp_tty_lock, flags);
105 return count;
106}
107
108static void
109sclp_ttybuf_callback(struct sclp_buffer *buffer, int rc)
110{
111 unsigned long flags;
112 void *page;
113
114 do {
115 page = sclp_unmake_buffer(buffer);
116 spin_lock_irqsave(&sclp_tty_lock, flags);
117 /* Remove buffer from outqueue */
118 list_del(&buffer->list);
119 sclp_tty_buffer_count--;
120 list_add_tail((struct list_head *) page, &sclp_tty_pages);
121 /* Check if there is a pending buffer on the out queue. */
122 buffer = NULL;
123 if (!list_empty(&sclp_tty_outqueue))
124 buffer = list_entry(sclp_tty_outqueue.next,
125 struct sclp_buffer, list);
126 spin_unlock_irqrestore(&sclp_tty_lock, flags);
127 } while (buffer && sclp_emit_buffer(buffer, sclp_ttybuf_callback));
128 /* check if the tty needs a wake up call */
129 if (sclp_tty != NULL) {
130 tty_wakeup(sclp_tty);
131 }
132}
133
134static inline void
135__sclp_ttybuf_emit(struct sclp_buffer *buffer)
136{
137 unsigned long flags;
138 int count;
139 int rc;
140
141 spin_lock_irqsave(&sclp_tty_lock, flags);
142 list_add_tail(&buffer->list, &sclp_tty_outqueue);
143 count = sclp_tty_buffer_count++;
144 spin_unlock_irqrestore(&sclp_tty_lock, flags);
145 if (count)
146 return;
147 rc = sclp_emit_buffer(buffer, sclp_ttybuf_callback);
148 if (rc)
149 sclp_ttybuf_callback(buffer, rc);
150}
151
152/*
153 * When this routine is called from the timer then we flush the
154 * temporary write buffer.
155 */
156static void
157sclp_tty_timeout(unsigned long data)
158{
159 unsigned long flags;
160 struct sclp_buffer *buf;
161
162 spin_lock_irqsave(&sclp_tty_lock, flags);
163 buf = sclp_ttybuf;
164 sclp_ttybuf = NULL;
165 spin_unlock_irqrestore(&sclp_tty_lock, flags);
166
167 if (buf != NULL) {
168 __sclp_ttybuf_emit(buf);
169 }
170}
171
172/*
173 * Write a string to the sclp tty.
174 */
175static int sclp_tty_write_string(const unsigned char *str, int count, int may_fail)
176{
177 unsigned long flags;
178 void *page;
179 int written;
180 int overall_written;
181 struct sclp_buffer *buf;
182
183 if (count <= 0)
184 return 0;
185 overall_written = 0;
186 spin_lock_irqsave(&sclp_tty_lock, flags);
187 do {
188 /* Create a sclp output buffer if none exists yet */
189 if (sclp_ttybuf == NULL) {
190 while (list_empty(&sclp_tty_pages)) {
191 spin_unlock_irqrestore(&sclp_tty_lock, flags);
192 if (may_fail)
193 goto out;
194 else
195 sclp_sync_wait();
196 spin_lock_irqsave(&sclp_tty_lock, flags);
197 }
198 page = sclp_tty_pages.next;
199 list_del((struct list_head *) page);
200 sclp_ttybuf = sclp_make_buffer(page, sclp_tty_columns,
201 SPACES_PER_TAB);
202 }
203 /* try to write the string to the current output buffer */
204 written = sclp_write(sclp_ttybuf, str, count);
205 overall_written += written;
206 if (written == count)
207 break;
208 /*
209 * Not all characters could be written to the current
210 * output buffer. Emit the buffer, create a new buffer
211 * and then output the rest of the string.
212 */
213 buf = sclp_ttybuf;
214 sclp_ttybuf = NULL;
215 spin_unlock_irqrestore(&sclp_tty_lock, flags);
216 __sclp_ttybuf_emit(buf);
217 spin_lock_irqsave(&sclp_tty_lock, flags);
218 str += written;
219 count -= written;
220 } while (count > 0);
221 /* Setup timer to output current console buffer after 1/10 second */
222 if (sclp_ttybuf && sclp_chars_in_buffer(sclp_ttybuf) &&
223 !timer_pending(&sclp_tty_timer)) {
224 init_timer(&sclp_tty_timer);
225 sclp_tty_timer.function = sclp_tty_timeout;
226 sclp_tty_timer.data = 0UL;
227 sclp_tty_timer.expires = jiffies + HZ/10;
228 add_timer(&sclp_tty_timer);
229 }
230 spin_unlock_irqrestore(&sclp_tty_lock, flags);
231out:
232 return overall_written;
233}
234
235/*
236 * This routine is called by the kernel to write a series of characters to the
237 * tty device. The characters may come from user space or kernel space. This
238 * routine will return the number of characters actually accepted for writing.
239 */
240static int
241sclp_tty_write(struct tty_struct *tty, const unsigned char *buf, int count)
242{
243 if (sclp_tty_chars_count > 0) {
244 sclp_tty_write_string(sclp_tty_chars, sclp_tty_chars_count, 0);
245 sclp_tty_chars_count = 0;
246 }
247 return sclp_tty_write_string(buf, count, 1);
248}
249
250/*
251 * This routine is called by the kernel to write a single character to the tty
252 * device. If the kernel uses this routine, it must call the flush_chars()
253 * routine (if defined) when it is done stuffing characters into the driver.
254 *
255 * Characters provided to sclp_tty_put_char() are buffered by the SCLP driver.
256 * If the given character is a '\n' the contents of the SCLP write buffer
257 * - including previous characters from sclp_tty_put_char() and strings from
258 * sclp_write() without final '\n' - will be written.
259 */
260static int
261sclp_tty_put_char(struct tty_struct *tty, unsigned char ch)
262{
263 sclp_tty_chars[sclp_tty_chars_count++] = ch;
264 if (ch == '\n' || sclp_tty_chars_count >= SCLP_TTY_BUF_SIZE) {
265 sclp_tty_write_string(sclp_tty_chars, sclp_tty_chars_count, 0);
266 sclp_tty_chars_count = 0;
267 }
268 return 1;
269}
270
271/*
272 * This routine is called by the kernel after it has written a series of
273 * characters to the tty device using put_char().
274 */
275static void
276sclp_tty_flush_chars(struct tty_struct *tty)
277{
278 if (sclp_tty_chars_count > 0) {
279 sclp_tty_write_string(sclp_tty_chars, sclp_tty_chars_count, 0);
280 sclp_tty_chars_count = 0;
281 }
282}
283
284/*
285 * This routine returns the number of characters in the write buffer of the
286 * SCLP driver. The provided number includes all characters that are stored
287 * in the SCCB (will be written next time the SCLP is not busy) as well as
288 * characters in the write buffer (will not be written as long as there is a
289 * final line feed missing).
290 */
291static int
292sclp_tty_chars_in_buffer(struct tty_struct *tty)
293{
294 unsigned long flags;
295 struct list_head *l;
296 struct sclp_buffer *t;
297 int count;
298
299 spin_lock_irqsave(&sclp_tty_lock, flags);
300 count = 0;
301 if (sclp_ttybuf != NULL)
302 count = sclp_chars_in_buffer(sclp_ttybuf);
303 list_for_each(l, &sclp_tty_outqueue) {
304 t = list_entry(l, struct sclp_buffer, list);
305 count += sclp_chars_in_buffer(t);
306 }
307 spin_unlock_irqrestore(&sclp_tty_lock, flags);
308 return count;
309}
310
311/*
312 * removes all content from buffers of low level driver
313 */
314static void
315sclp_tty_flush_buffer(struct tty_struct *tty)
316{
317 if (sclp_tty_chars_count > 0) {
318 sclp_tty_write_string(sclp_tty_chars, sclp_tty_chars_count, 0);
319 sclp_tty_chars_count = 0;
320 }
321}
322
323/*
324 * push input to tty
325 */
326static void
327sclp_tty_input(unsigned char* buf, unsigned int count)
328{
329 unsigned int cchar;
330
331 /*
332 * If this tty driver is currently closed
333 * then throw the received input away.
334 */
335 if (sclp_tty == NULL)
336 return;
337 cchar = ctrlchar_handle(buf, count, sclp_tty);
338 switch (cchar & CTRLCHAR_MASK) {
339 case CTRLCHAR_SYSRQ:
340 break;
341 case CTRLCHAR_CTRL:
342 tty_insert_flip_char(sclp_tty, cchar, TTY_NORMAL);
343 tty_flip_buffer_push(sclp_tty);
344 break;
345 case CTRLCHAR_NONE:
346 /* send (normal) input to line discipline */
347 if (count < 2 ||
348 (strncmp((const char *) buf + count - 2, "^n", 2) &&
349 strncmp((const char *) buf + count - 2, "\252n", 2))) {
350 /* add the auto \n */
351 tty_insert_flip_string(sclp_tty, buf, count);
352 tty_insert_flip_char(sclp_tty, '\n', TTY_NORMAL);
353 } else
354 tty_insert_flip_string(sclp_tty, buf, count - 2);
355 tty_flip_buffer_push(sclp_tty);
356 break;
357 }
358}
359
360/*
361 * get a EBCDIC string in upper/lower case,
362 * find out characters in lower/upper case separated by a special character,
363 * modifiy original string,
364 * returns length of resulting string
365 */
366static int sclp_switch_cases(unsigned char *buf, int count)
367{
368 unsigned char *ip, *op;
369 int toggle;
370
371 /* initially changing case is off */
372 toggle = 0;
373 ip = op = buf;
374 while (count-- > 0) {
375 /* compare with special character */
376 if (*ip == CASE_DELIMITER) {
377 /* followed by another special character? */
378 if (count && ip[1] == CASE_DELIMITER) {
379 /*
380 * ... then put a single copy of the special
381 * character to the output string
382 */
383 *op++ = *ip++;
384 count--;
385 } else
386 /*
387 * ... special character follower by a normal
388 * character toggles the case change behaviour
389 */
390 toggle = ~toggle;
391 /* skip special character */
392 ip++;
393 } else
394 /* not the special character */
395 if (toggle)
396 /* but case switching is on */
397 if (sclp_tty_tolower)
398 /* switch to uppercase */
399 *op++ = _ebc_toupper[(int) *ip++];
400 else
401 /* switch to lowercase */
402 *op++ = _ebc_tolower[(int) *ip++];
403 else
404 /* no case switching, copy the character */
405 *op++ = *ip++;
406 }
407 /* return length of reformatted string. */
408 return op - buf;
409}
410
411static void sclp_get_input(struct gds_subvector *sv)
412{
413 unsigned char *str;
414 int count;
415
416 str = (unsigned char *) (sv + 1);
417 count = sv->length - sizeof(*sv);
418 if (sclp_tty_tolower)
419 EBC_TOLOWER(str, count);
420 count = sclp_switch_cases(str, count);
421 /* convert EBCDIC to ASCII (modify original input in SCCB) */
422 sclp_ebcasc_str(str, count);
423
424 /* transfer input to high level driver */
425 sclp_tty_input(str, count);
426}
427
428static inline void sclp_eval_selfdeftextmsg(struct gds_subvector *sv)
429{
430 void *end;
431
432 end = (void *) sv + sv->length;
433 for (sv = sv + 1; (void *) sv < end; sv = (void *) sv + sv->length)
434 if (sv->key == 0x30)
435 sclp_get_input(sv);
436}
437
438static inline void sclp_eval_textcmd(struct gds_vector *v)
439{
440 struct gds_subvector *sv;
441 void *end;
442
443 end = (void *) v + v->length;
444 for (sv = (struct gds_subvector *) (v + 1);
445 (void *) sv < end; sv = (void *) sv + sv->length)
446 if (sv->key == GDS_KEY_SELFDEFTEXTMSG)
447 sclp_eval_selfdeftextmsg(sv);
448
449}
450
451static inline void sclp_eval_cpmsu(struct gds_vector *v)
452{
453 void *end;
454
455 end = (void *) v + v->length;
456 for (v = v + 1; (void *) v < end; v = (void *) v + v->length)
457 if (v->gds_id == GDS_ID_TEXTCMD)
458 sclp_eval_textcmd(v);
459}
460
461
462static inline void sclp_eval_mdsmu(struct gds_vector *v)
463{
464 v = sclp_find_gds_vector(v + 1, (void *) v + v->length, GDS_ID_CPMSU);
465 if (v)
466 sclp_eval_cpmsu(v);
467}
468
469static void sclp_tty_receiver(struct evbuf_header *evbuf)
470{
471 struct gds_vector *v;
472
473 v = sclp_find_gds_vector(evbuf + 1, (void *) evbuf + evbuf->length,
474 GDS_ID_MDSMU);
475 if (v)
476 sclp_eval_mdsmu(v);
477}
478
479static void
480sclp_tty_state_change(struct sclp_register *reg)
481{
482}
483
484static struct sclp_register sclp_input_event =
485{
486 .receive_mask = EVTYP_OPCMD_MASK | EVTYP_PMSGCMD_MASK,
487 .state_change_fn = sclp_tty_state_change,
488 .receiver_fn = sclp_tty_receiver
489};
490
491static const struct tty_operations sclp_ops = {
492 .open = sclp_tty_open,
493 .close = sclp_tty_close,
494 .write = sclp_tty_write,
495 .put_char = sclp_tty_put_char,
496 .flush_chars = sclp_tty_flush_chars,
497 .write_room = sclp_tty_write_room,
498 .chars_in_buffer = sclp_tty_chars_in_buffer,
499 .flush_buffer = sclp_tty_flush_buffer,
500};
501
502static int __init
503sclp_tty_init(void)
504{
505 struct tty_driver *driver;
506 void *page;
507 int i;
508 int rc;
509
510 if (!CONSOLE_IS_SCLP)
511 return 0;
512 driver = alloc_tty_driver(1);
513 if (!driver)
514 return -ENOMEM;
515
516 rc = sclp_rw_init();
517 if (rc) {
518 put_tty_driver(driver);
519 return rc;
520 }
521 /* Allocate pages for output buffering */
522 INIT_LIST_HEAD(&sclp_tty_pages);
523 for (i = 0; i < MAX_KMEM_PAGES; i++) {
524 page = (void *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
525 if (page == NULL) {
526 put_tty_driver(driver);
527 return -ENOMEM;
528 }
529 list_add_tail((struct list_head *) page, &sclp_tty_pages);
530 }
531 INIT_LIST_HEAD(&sclp_tty_outqueue);
532 spin_lock_init(&sclp_tty_lock);
533 init_timer(&sclp_tty_timer);
534 sclp_ttybuf = NULL;
535 sclp_tty_buffer_count = 0;
536 if (MACHINE_IS_VM) {
537 /*
538 * save 4 characters for the CPU number
539 * written at start of each line by VM/CP
540 */
541 sclp_tty_columns = 76;
542 /* case input lines to lowercase */
543 sclp_tty_tolower = 1;
544 }
545 sclp_tty_chars_count = 0;
546 sclp_tty = NULL;
547
548 rc = sclp_register(&sclp_input_event);
549 if (rc) {
550 put_tty_driver(driver);
551 return rc;
552 }
553
554 driver->owner = THIS_MODULE;
555 driver->driver_name = "sclp_line";
556 driver->name = "sclp_line";
557 driver->major = TTY_MAJOR;
558 driver->minor_start = 64;
559 driver->type = TTY_DRIVER_TYPE_SYSTEM;
560 driver->subtype = SYSTEM_TYPE_TTY;
561 driver->init_termios = tty_std_termios;
562 driver->init_termios.c_iflag = IGNBRK | IGNPAR;
563 driver->init_termios.c_oflag = ONLCR | XTABS;
564 driver->init_termios.c_lflag = ISIG | ECHO;
565 driver->flags = TTY_DRIVER_REAL_RAW;
566 tty_set_operations(driver, &sclp_ops);
567 rc = tty_register_driver(driver);
568 if (rc) {
569 put_tty_driver(driver);
570 return rc;
571 }
572 sclp_tty_driver = driver;
573 return 0;
574}
575module_init(sclp_tty_init);
1/*
2 * SCLP line mode terminal driver.
3 *
4 * S390 version
5 * Copyright IBM Corp. 1999
6 * Author(s): Martin Peschke <mpeschke@de.ibm.com>
7 * Martin Schwidefsky <schwidefsky@de.ibm.com>
8 */
9
10#include <linux/module.h>
11#include <linux/kmod.h>
12#include <linux/tty.h>
13#include <linux/tty_driver.h>
14#include <linux/tty_flip.h>
15#include <linux/err.h>
16#include <linux/init.h>
17#include <linux/interrupt.h>
18#include <linux/gfp.h>
19#include <asm/uaccess.h>
20
21#include "ctrlchar.h"
22#include "sclp.h"
23#include "sclp_rw.h"
24#include "sclp_tty.h"
25
26/*
27 * size of a buffer that collects single characters coming in
28 * via sclp_tty_put_char()
29 */
30#define SCLP_TTY_BUF_SIZE 512
31
32/*
33 * There is exactly one SCLP terminal, so we can keep things simple
34 * and allocate all variables statically.
35 */
36
37/* Lock to guard over changes to global variables. */
38static spinlock_t sclp_tty_lock;
39/* List of free pages that can be used for console output buffering. */
40static struct list_head sclp_tty_pages;
41/* List of full struct sclp_buffer structures ready for output. */
42static struct list_head sclp_tty_outqueue;
43/* Counter how many buffers are emitted. */
44static int sclp_tty_buffer_count;
45/* Pointer to current console buffer. */
46static struct sclp_buffer *sclp_ttybuf;
47/* Timer for delayed output of console messages. */
48static struct timer_list sclp_tty_timer;
49
50static struct tty_port sclp_port;
51static unsigned char sclp_tty_chars[SCLP_TTY_BUF_SIZE];
52static unsigned short int sclp_tty_chars_count;
53
54struct tty_driver *sclp_tty_driver;
55
56static int sclp_tty_tolower;
57static int sclp_tty_columns = 80;
58
59#define SPACES_PER_TAB 8
60#define CASE_DELIMITER 0x6c /* to separate upper and lower case (% in EBCDIC) */
61
62/* This routine is called whenever we try to open a SCLP terminal. */
63static int
64sclp_tty_open(struct tty_struct *tty, struct file *filp)
65{
66 tty_port_tty_set(&sclp_port, tty);
67 tty->driver_data = NULL;
68 sclp_port.low_latency = 0;
69 return 0;
70}
71
72/* This routine is called when the SCLP terminal is closed. */
73static void
74sclp_tty_close(struct tty_struct *tty, struct file *filp)
75{
76 if (tty->count > 1)
77 return;
78 tty_port_tty_set(&sclp_port, NULL);
79}
80
81/*
82 * This routine returns the numbers of characters the tty driver
83 * will accept for queuing to be written. This number is subject
84 * to change as output buffers get emptied, or if the output flow
85 * control is acted. This is not an exact number because not every
86 * character needs the same space in the sccb. The worst case is
87 * a string of newlines. Every newline creates a new message which
88 * needs 82 bytes.
89 */
90static int
91sclp_tty_write_room (struct tty_struct *tty)
92{
93 unsigned long flags;
94 struct list_head *l;
95 int count;
96
97 spin_lock_irqsave(&sclp_tty_lock, flags);
98 count = 0;
99 if (sclp_ttybuf != NULL)
100 count = sclp_buffer_space(sclp_ttybuf) / sizeof(struct msg_buf);
101 list_for_each(l, &sclp_tty_pages)
102 count += NR_EMPTY_MSG_PER_SCCB;
103 spin_unlock_irqrestore(&sclp_tty_lock, flags);
104 return count;
105}
106
107static void
108sclp_ttybuf_callback(struct sclp_buffer *buffer, int rc)
109{
110 unsigned long flags;
111 void *page;
112
113 do {
114 page = sclp_unmake_buffer(buffer);
115 spin_lock_irqsave(&sclp_tty_lock, flags);
116 /* Remove buffer from outqueue */
117 list_del(&buffer->list);
118 sclp_tty_buffer_count--;
119 list_add_tail((struct list_head *) page, &sclp_tty_pages);
120 /* Check if there is a pending buffer on the out queue. */
121 buffer = NULL;
122 if (!list_empty(&sclp_tty_outqueue))
123 buffer = list_entry(sclp_tty_outqueue.next,
124 struct sclp_buffer, list);
125 spin_unlock_irqrestore(&sclp_tty_lock, flags);
126 } while (buffer && sclp_emit_buffer(buffer, sclp_ttybuf_callback));
127
128 tty_port_tty_wakeup(&sclp_port);
129}
130
131static inline void
132__sclp_ttybuf_emit(struct sclp_buffer *buffer)
133{
134 unsigned long flags;
135 int count;
136 int rc;
137
138 spin_lock_irqsave(&sclp_tty_lock, flags);
139 list_add_tail(&buffer->list, &sclp_tty_outqueue);
140 count = sclp_tty_buffer_count++;
141 spin_unlock_irqrestore(&sclp_tty_lock, flags);
142 if (count)
143 return;
144 rc = sclp_emit_buffer(buffer, sclp_ttybuf_callback);
145 if (rc)
146 sclp_ttybuf_callback(buffer, rc);
147}
148
149/*
150 * When this routine is called from the timer then we flush the
151 * temporary write buffer.
152 */
153static void
154sclp_tty_timeout(unsigned long data)
155{
156 unsigned long flags;
157 struct sclp_buffer *buf;
158
159 spin_lock_irqsave(&sclp_tty_lock, flags);
160 buf = sclp_ttybuf;
161 sclp_ttybuf = NULL;
162 spin_unlock_irqrestore(&sclp_tty_lock, flags);
163
164 if (buf != NULL) {
165 __sclp_ttybuf_emit(buf);
166 }
167}
168
169/*
170 * Write a string to the sclp tty.
171 */
172static int sclp_tty_write_string(const unsigned char *str, int count, int may_fail)
173{
174 unsigned long flags;
175 void *page;
176 int written;
177 int overall_written;
178 struct sclp_buffer *buf;
179
180 if (count <= 0)
181 return 0;
182 overall_written = 0;
183 spin_lock_irqsave(&sclp_tty_lock, flags);
184 do {
185 /* Create a sclp output buffer if none exists yet */
186 if (sclp_ttybuf == NULL) {
187 while (list_empty(&sclp_tty_pages)) {
188 spin_unlock_irqrestore(&sclp_tty_lock, flags);
189 if (may_fail)
190 goto out;
191 else
192 sclp_sync_wait();
193 spin_lock_irqsave(&sclp_tty_lock, flags);
194 }
195 page = sclp_tty_pages.next;
196 list_del((struct list_head *) page);
197 sclp_ttybuf = sclp_make_buffer(page, sclp_tty_columns,
198 SPACES_PER_TAB);
199 }
200 /* try to write the string to the current output buffer */
201 written = sclp_write(sclp_ttybuf, str, count);
202 overall_written += written;
203 if (written == count)
204 break;
205 /*
206 * Not all characters could be written to the current
207 * output buffer. Emit the buffer, create a new buffer
208 * and then output the rest of the string.
209 */
210 buf = sclp_ttybuf;
211 sclp_ttybuf = NULL;
212 spin_unlock_irqrestore(&sclp_tty_lock, flags);
213 __sclp_ttybuf_emit(buf);
214 spin_lock_irqsave(&sclp_tty_lock, flags);
215 str += written;
216 count -= written;
217 } while (count > 0);
218 /* Setup timer to output current console buffer after 1/10 second */
219 if (sclp_ttybuf && sclp_chars_in_buffer(sclp_ttybuf) &&
220 !timer_pending(&sclp_tty_timer)) {
221 init_timer(&sclp_tty_timer);
222 sclp_tty_timer.function = sclp_tty_timeout;
223 sclp_tty_timer.data = 0UL;
224 sclp_tty_timer.expires = jiffies + HZ/10;
225 add_timer(&sclp_tty_timer);
226 }
227 spin_unlock_irqrestore(&sclp_tty_lock, flags);
228out:
229 return overall_written;
230}
231
232/*
233 * This routine is called by the kernel to write a series of characters to the
234 * tty device. The characters may come from user space or kernel space. This
235 * routine will return the number of characters actually accepted for writing.
236 */
237static int
238sclp_tty_write(struct tty_struct *tty, const unsigned char *buf, int count)
239{
240 if (sclp_tty_chars_count > 0) {
241 sclp_tty_write_string(sclp_tty_chars, sclp_tty_chars_count, 0);
242 sclp_tty_chars_count = 0;
243 }
244 return sclp_tty_write_string(buf, count, 1);
245}
246
247/*
248 * This routine is called by the kernel to write a single character to the tty
249 * device. If the kernel uses this routine, it must call the flush_chars()
250 * routine (if defined) when it is done stuffing characters into the driver.
251 *
252 * Characters provided to sclp_tty_put_char() are buffered by the SCLP driver.
253 * If the given character is a '\n' the contents of the SCLP write buffer
254 * - including previous characters from sclp_tty_put_char() and strings from
255 * sclp_write() without final '\n' - will be written.
256 */
257static int
258sclp_tty_put_char(struct tty_struct *tty, unsigned char ch)
259{
260 sclp_tty_chars[sclp_tty_chars_count++] = ch;
261 if (ch == '\n' || sclp_tty_chars_count >= SCLP_TTY_BUF_SIZE) {
262 sclp_tty_write_string(sclp_tty_chars, sclp_tty_chars_count, 0);
263 sclp_tty_chars_count = 0;
264 }
265 return 1;
266}
267
268/*
269 * This routine is called by the kernel after it has written a series of
270 * characters to the tty device using put_char().
271 */
272static void
273sclp_tty_flush_chars(struct tty_struct *tty)
274{
275 if (sclp_tty_chars_count > 0) {
276 sclp_tty_write_string(sclp_tty_chars, sclp_tty_chars_count, 0);
277 sclp_tty_chars_count = 0;
278 }
279}
280
281/*
282 * This routine returns the number of characters in the write buffer of the
283 * SCLP driver. The provided number includes all characters that are stored
284 * in the SCCB (will be written next time the SCLP is not busy) as well as
285 * characters in the write buffer (will not be written as long as there is a
286 * final line feed missing).
287 */
288static int
289sclp_tty_chars_in_buffer(struct tty_struct *tty)
290{
291 unsigned long flags;
292 struct list_head *l;
293 struct sclp_buffer *t;
294 int count;
295
296 spin_lock_irqsave(&sclp_tty_lock, flags);
297 count = 0;
298 if (sclp_ttybuf != NULL)
299 count = sclp_chars_in_buffer(sclp_ttybuf);
300 list_for_each(l, &sclp_tty_outqueue) {
301 t = list_entry(l, struct sclp_buffer, list);
302 count += sclp_chars_in_buffer(t);
303 }
304 spin_unlock_irqrestore(&sclp_tty_lock, flags);
305 return count;
306}
307
308/*
309 * removes all content from buffers of low level driver
310 */
311static void
312sclp_tty_flush_buffer(struct tty_struct *tty)
313{
314 if (sclp_tty_chars_count > 0) {
315 sclp_tty_write_string(sclp_tty_chars, sclp_tty_chars_count, 0);
316 sclp_tty_chars_count = 0;
317 }
318}
319
320/*
321 * push input to tty
322 */
323static void
324sclp_tty_input(unsigned char* buf, unsigned int count)
325{
326 struct tty_struct *tty = tty_port_tty_get(&sclp_port);
327 unsigned int cchar;
328
329 /*
330 * If this tty driver is currently closed
331 * then throw the received input away.
332 */
333 if (tty == NULL)
334 return;
335 cchar = ctrlchar_handle(buf, count, tty);
336 switch (cchar & CTRLCHAR_MASK) {
337 case CTRLCHAR_SYSRQ:
338 break;
339 case CTRLCHAR_CTRL:
340 tty_insert_flip_char(&sclp_port, cchar, TTY_NORMAL);
341 tty_flip_buffer_push(&sclp_port);
342 break;
343 case CTRLCHAR_NONE:
344 /* send (normal) input to line discipline */
345 if (count < 2 ||
346 (strncmp((const char *) buf + count - 2, "^n", 2) &&
347 strncmp((const char *) buf + count - 2, "\252n", 2))) {
348 /* add the auto \n */
349 tty_insert_flip_string(&sclp_port, buf, count);
350 tty_insert_flip_char(&sclp_port, '\n', TTY_NORMAL);
351 } else
352 tty_insert_flip_string(&sclp_port, buf, count - 2);
353 tty_flip_buffer_push(&sclp_port);
354 break;
355 }
356 tty_kref_put(tty);
357}
358
359/*
360 * get a EBCDIC string in upper/lower case,
361 * find out characters in lower/upper case separated by a special character,
362 * modifiy original string,
363 * returns length of resulting string
364 */
365static int sclp_switch_cases(unsigned char *buf, int count)
366{
367 unsigned char *ip, *op;
368 int toggle;
369
370 /* initially changing case is off */
371 toggle = 0;
372 ip = op = buf;
373 while (count-- > 0) {
374 /* compare with special character */
375 if (*ip == CASE_DELIMITER) {
376 /* followed by another special character? */
377 if (count && ip[1] == CASE_DELIMITER) {
378 /*
379 * ... then put a single copy of the special
380 * character to the output string
381 */
382 *op++ = *ip++;
383 count--;
384 } else
385 /*
386 * ... special character follower by a normal
387 * character toggles the case change behaviour
388 */
389 toggle = ~toggle;
390 /* skip special character */
391 ip++;
392 } else
393 /* not the special character */
394 if (toggle)
395 /* but case switching is on */
396 if (sclp_tty_tolower)
397 /* switch to uppercase */
398 *op++ = _ebc_toupper[(int) *ip++];
399 else
400 /* switch to lowercase */
401 *op++ = _ebc_tolower[(int) *ip++];
402 else
403 /* no case switching, copy the character */
404 *op++ = *ip++;
405 }
406 /* return length of reformatted string. */
407 return op - buf;
408}
409
410static void sclp_get_input(struct gds_subvector *sv)
411{
412 unsigned char *str;
413 int count;
414
415 str = (unsigned char *) (sv + 1);
416 count = sv->length - sizeof(*sv);
417 if (sclp_tty_tolower)
418 EBC_TOLOWER(str, count);
419 count = sclp_switch_cases(str, count);
420 /* convert EBCDIC to ASCII (modify original input in SCCB) */
421 sclp_ebcasc_str(str, count);
422
423 /* transfer input to high level driver */
424 sclp_tty_input(str, count);
425}
426
427static inline void sclp_eval_selfdeftextmsg(struct gds_subvector *sv)
428{
429 void *end;
430
431 end = (void *) sv + sv->length;
432 for (sv = sv + 1; (void *) sv < end; sv = (void *) sv + sv->length)
433 if (sv->key == 0x30)
434 sclp_get_input(sv);
435}
436
437static inline void sclp_eval_textcmd(struct gds_vector *v)
438{
439 struct gds_subvector *sv;
440 void *end;
441
442 end = (void *) v + v->length;
443 for (sv = (struct gds_subvector *) (v + 1);
444 (void *) sv < end; sv = (void *) sv + sv->length)
445 if (sv->key == GDS_KEY_SELFDEFTEXTMSG)
446 sclp_eval_selfdeftextmsg(sv);
447
448}
449
450static inline void sclp_eval_cpmsu(struct gds_vector *v)
451{
452 void *end;
453
454 end = (void *) v + v->length;
455 for (v = v + 1; (void *) v < end; v = (void *) v + v->length)
456 if (v->gds_id == GDS_ID_TEXTCMD)
457 sclp_eval_textcmd(v);
458}
459
460
461static inline void sclp_eval_mdsmu(struct gds_vector *v)
462{
463 v = sclp_find_gds_vector(v + 1, (void *) v + v->length, GDS_ID_CPMSU);
464 if (v)
465 sclp_eval_cpmsu(v);
466}
467
468static void sclp_tty_receiver(struct evbuf_header *evbuf)
469{
470 struct gds_vector *v;
471
472 v = sclp_find_gds_vector(evbuf + 1, (void *) evbuf + evbuf->length,
473 GDS_ID_MDSMU);
474 if (v)
475 sclp_eval_mdsmu(v);
476}
477
478static void
479sclp_tty_state_change(struct sclp_register *reg)
480{
481}
482
483static struct sclp_register sclp_input_event =
484{
485 .receive_mask = EVTYP_OPCMD_MASK | EVTYP_PMSGCMD_MASK,
486 .state_change_fn = sclp_tty_state_change,
487 .receiver_fn = sclp_tty_receiver
488};
489
490static const struct tty_operations sclp_ops = {
491 .open = sclp_tty_open,
492 .close = sclp_tty_close,
493 .write = sclp_tty_write,
494 .put_char = sclp_tty_put_char,
495 .flush_chars = sclp_tty_flush_chars,
496 .write_room = sclp_tty_write_room,
497 .chars_in_buffer = sclp_tty_chars_in_buffer,
498 .flush_buffer = sclp_tty_flush_buffer,
499};
500
501static int __init
502sclp_tty_init(void)
503{
504 struct tty_driver *driver;
505 void *page;
506 int i;
507 int rc;
508
509 if (!CONSOLE_IS_SCLP)
510 return 0;
511 driver = alloc_tty_driver(1);
512 if (!driver)
513 return -ENOMEM;
514
515 rc = sclp_rw_init();
516 if (rc) {
517 put_tty_driver(driver);
518 return rc;
519 }
520 /* Allocate pages for output buffering */
521 INIT_LIST_HEAD(&sclp_tty_pages);
522 for (i = 0; i < MAX_KMEM_PAGES; i++) {
523 page = (void *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
524 if (page == NULL) {
525 put_tty_driver(driver);
526 return -ENOMEM;
527 }
528 list_add_tail((struct list_head *) page, &sclp_tty_pages);
529 }
530 INIT_LIST_HEAD(&sclp_tty_outqueue);
531 spin_lock_init(&sclp_tty_lock);
532 init_timer(&sclp_tty_timer);
533 sclp_ttybuf = NULL;
534 sclp_tty_buffer_count = 0;
535 if (MACHINE_IS_VM) {
536 /*
537 * save 4 characters for the CPU number
538 * written at start of each line by VM/CP
539 */
540 sclp_tty_columns = 76;
541 /* case input lines to lowercase */
542 sclp_tty_tolower = 1;
543 }
544 sclp_tty_chars_count = 0;
545
546 rc = sclp_register(&sclp_input_event);
547 if (rc) {
548 put_tty_driver(driver);
549 return rc;
550 }
551
552 tty_port_init(&sclp_port);
553
554 driver->driver_name = "sclp_line";
555 driver->name = "sclp_line";
556 driver->major = TTY_MAJOR;
557 driver->minor_start = 64;
558 driver->type = TTY_DRIVER_TYPE_SYSTEM;
559 driver->subtype = SYSTEM_TYPE_TTY;
560 driver->init_termios = tty_std_termios;
561 driver->init_termios.c_iflag = IGNBRK | IGNPAR;
562 driver->init_termios.c_oflag = ONLCR;
563 driver->init_termios.c_lflag = ISIG | ECHO;
564 driver->flags = TTY_DRIVER_REAL_RAW;
565 tty_set_operations(driver, &sclp_ops);
566 tty_port_link_device(&sclp_port, driver, 0);
567 rc = tty_register_driver(driver);
568 if (rc) {
569 put_tty_driver(driver);
570 tty_port_destroy(&sclp_port);
571 return rc;
572 }
573 sclp_tty_driver = driver;
574 return 0;
575}
576module_init(sclp_tty_init);