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1/*
2 *    IBM/3270 Driver - tty functions.
3 *
4 *  Author(s):
5 *    Original 3270 Code for 2.4 written by Richard Hitt (UTS Global)
6 *    Rewritten for 2.5 by Martin Schwidefsky <schwidefsky@de.ibm.com>
7 *	-- Copyright IBM Corp. 2003
8 */
9
10#include <linux/module.h>
11#include <linux/types.h>
12#include <linux/kdev_t.h>
13#include <linux/tty.h>
14#include <linux/vt_kern.h>
15#include <linux/init.h>
16#include <linux/console.h>
17#include <linux/interrupt.h>
18#include <linux/workqueue.h>
19
20#include <linux/slab.h>
21#include <linux/bootmem.h>
22#include <linux/compat.h>
23
24#include <asm/ccwdev.h>
25#include <asm/cio.h>
26#include <asm/ebcdic.h>
27#include <asm/uaccess.h>
28
29#include "raw3270.h"
30#include "tty3270.h"
31#include "keyboard.h"
32
33#define TTY3270_CHAR_BUF_SIZE 256
34#define TTY3270_OUTPUT_BUFFER_SIZE 1024
35#define TTY3270_STRING_PAGES 5
36
37struct tty_driver *tty3270_driver;
38static int tty3270_max_index;
39
40static struct raw3270_fn tty3270_fn;
41
42struct tty3270_cell {
43	unsigned char character;
44	unsigned char highlight;
45	unsigned char f_color;
46};
47
48struct tty3270_line {
49	struct tty3270_cell *cells;
50	int len;
51};
52
53#define ESCAPE_NPAR 8
54
55/*
56 * The main tty view data structure.
57 * FIXME:
58 * 1) describe line orientation & lines list concept against screen
59 * 2) describe conversion of screen to lines
60 * 3) describe line format.
61 */
62struct tty3270 {
63	struct raw3270_view view;
64	struct tty_port port;
65	void **freemem_pages;		/* Array of pages used for freemem. */
66	struct list_head freemem;	/* List of free memory for strings. */
67
68	/* Output stuff. */
69	struct list_head lines;		/* List of lines. */
70	struct list_head update;	/* List of lines to update. */
71	unsigned char wcc;		/* Write control character. */
72	int nr_lines;			/* # lines in list. */
73	int nr_up;			/* # lines up in history. */
74	unsigned long update_flags;	/* Update indication bits. */
75	struct string *status;		/* Lower right of display. */
76	struct raw3270_request *write;	/* Single write request. */
77	struct timer_list timer;	/* Output delay timer. */
78
79	/* Current tty screen. */
80	unsigned int cx, cy;		/* Current output position. */
81	unsigned int highlight;		/* Blink/reverse/underscore */
82	unsigned int f_color;		/* Foreground color */
83	struct tty3270_line *screen;
84	unsigned int n_model, n_cols, n_rows;	/* New model & size */
85	struct work_struct resize_work;
86
87	/* Input stuff. */
88	struct string *prompt;		/* Output string for input area. */
89	struct string *input;		/* Input string for read request. */
90	struct raw3270_request *read;	/* Single read request. */
91	struct raw3270_request *kreset;	/* Single keyboard reset request. */
92	unsigned char inattr;		/* Visible/invisible input. */
93	int throttle, attn;		/* tty throttle/unthrottle. */
94	struct tasklet_struct readlet;	/* Tasklet to issue read request. */
95	struct kbd_data *kbd;		/* key_maps stuff. */
96
97	/* Escape sequence parsing. */
98	int esc_state, esc_ques, esc_npar;
99	int esc_par[ESCAPE_NPAR];
100	unsigned int saved_cx, saved_cy;
101	unsigned int saved_highlight, saved_f_color;
102
103	/* Command recalling. */
104	struct list_head rcl_lines;	/* List of recallable lines. */
105	struct list_head *rcl_walk;	/* Point in rcl_lines list. */
106	int rcl_nr, rcl_max;		/* Number/max number of rcl_lines. */
107
108	/* Character array for put_char/flush_chars. */
109	unsigned int char_count;
110	char char_buf[TTY3270_CHAR_BUF_SIZE];
111};
112
113/* tty3270->update_flags. See tty3270_update for details. */
114#define TTY_UPDATE_ERASE	1	/* Use EWRITEA instead of WRITE. */
115#define TTY_UPDATE_LIST		2	/* Update lines in tty3270->update. */
116#define TTY_UPDATE_INPUT	4	/* Update input line. */
117#define TTY_UPDATE_STATUS	8	/* Update status line. */
118#define TTY_UPDATE_ALL		16	/* Recreate screen. */
119
120static void tty3270_update(struct tty3270 *);
121static void tty3270_resize_work(struct work_struct *work);
122
123/*
124 * Setup timeout for a device. On timeout trigger an update.
125 */
126static void tty3270_set_timer(struct tty3270 *tp, int expires)
127{
128	mod_timer(&tp->timer, jiffies + expires);
129}
130
131/*
132 * The input line are the two last lines of the screen.
133 */
134static void
135tty3270_update_prompt(struct tty3270 *tp, char *input, int count)
136{
137	struct string *line;
138	unsigned int off;
139
140	line = tp->prompt;
141	if (count != 0)
142		line->string[5] = TF_INMDT;
143	else
144		line->string[5] = tp->inattr;
145	if (count > tp->view.cols * 2 - 11)
146		count = tp->view.cols * 2 - 11;
147	memcpy(line->string + 6, input, count);
148	line->string[6 + count] = TO_IC;
149	/* Clear to end of input line. */
150	if (count < tp->view.cols * 2 - 11) {
151		line->string[7 + count] = TO_RA;
152		line->string[10 + count] = 0;
153		off = tp->view.cols * tp->view.rows - 9;
154		raw3270_buffer_address(tp->view.dev, line->string+count+8, off);
155		line->len = 11 + count;
156	} else
157		line->len = 7 + count;
158	tp->update_flags |= TTY_UPDATE_INPUT;
159}
160
161static void
162tty3270_create_prompt(struct tty3270 *tp)
163{
164	static const unsigned char blueprint[] =
165		{ TO_SBA, 0, 0, 0x6e, TO_SF, TF_INPUT,
166		  /* empty input string */
167		  TO_IC, TO_RA, 0, 0, 0 };
168	struct string *line;
169	unsigned int offset;
170
171	line = alloc_string(&tp->freemem,
172			    sizeof(blueprint) + tp->view.cols * 2 - 9);
173	tp->prompt = line;
174	tp->inattr = TF_INPUT;
175	/* Copy blueprint to status line */
176	memcpy(line->string, blueprint, sizeof(blueprint));
177	line->len = sizeof(blueprint);
178	/* Set output offsets. */
179	offset = tp->view.cols * (tp->view.rows - 2);
180	raw3270_buffer_address(tp->view.dev, line->string + 1, offset);
181	offset = tp->view.cols * tp->view.rows - 9;
182	raw3270_buffer_address(tp->view.dev, line->string + 8, offset);
183
184	/* Allocate input string for reading. */
185	tp->input = alloc_string(&tp->freemem, tp->view.cols * 2 - 9 + 6);
186}
187
188/*
189 * The status line is the last line of the screen. It shows the string
190 * "Running"/"Holding" in the lower right corner of the screen.
191 */
192static void
193tty3270_update_status(struct tty3270 * tp)
194{
195	char *str;
196
197	str = (tp->nr_up != 0) ? "History" : "Running";
198	memcpy(tp->status->string + 8, str, 7);
199	codepage_convert(tp->view.ascebc, tp->status->string + 8, 7);
200	tp->update_flags |= TTY_UPDATE_STATUS;
201}
202
203static void
204tty3270_create_status(struct tty3270 * tp)
205{
206	static const unsigned char blueprint[] =
207		{ TO_SBA, 0, 0, TO_SF, TF_LOG, TO_SA, TAT_COLOR, TAC_GREEN,
208		  0, 0, 0, 0, 0, 0, 0, TO_SF, TF_LOG, TO_SA, TAT_COLOR,
209		  TAC_RESET };
210	struct string *line;
211	unsigned int offset;
212
213	line = alloc_string(&tp->freemem,sizeof(blueprint));
214	tp->status = line;
215	/* Copy blueprint to status line */
216	memcpy(line->string, blueprint, sizeof(blueprint));
217	/* Set address to start of status string (= last 9 characters). */
218	offset = tp->view.cols * tp->view.rows - 9;
219	raw3270_buffer_address(tp->view.dev, line->string + 1, offset);
220}
221
222/*
223 * Set output offsets to 3270 datastream fragment of a tty string.
224 * (TO_SBA offset at the start and TO_RA offset at the end of the string)
225 */
226static void
227tty3270_update_string(struct tty3270 *tp, struct string *line, int nr)
228{
229	unsigned char *cp;
230
231	raw3270_buffer_address(tp->view.dev, line->string + 1,
232			       tp->view.cols * nr);
233	cp = line->string + line->len - 4;
234	if (*cp == TO_RA)
235		raw3270_buffer_address(tp->view.dev, cp + 1,
236				       tp->view.cols * (nr + 1));
237}
238
239/*
240 * Rebuild update list to print all lines.
241 */
242static void
243tty3270_rebuild_update(struct tty3270 *tp)
244{
245	struct string *s, *n;
246	int line, nr_up;
247
248	/*
249	 * Throw away update list and create a new one,
250	 * containing all lines that will fit on the screen.
251	 */
252	list_for_each_entry_safe(s, n, &tp->update, update)
253		list_del_init(&s->update);
254	line = tp->view.rows - 3;
255	nr_up = tp->nr_up;
256	list_for_each_entry_reverse(s, &tp->lines, list) {
257		if (nr_up > 0) {
258			nr_up--;
259			continue;
260		}
261		tty3270_update_string(tp, s, line);
262		list_add(&s->update, &tp->update);
263		if (--line < 0)
264			break;
265	}
266	tp->update_flags |= TTY_UPDATE_LIST;
267}
268
269/*
270 * Alloc string for size bytes. If there is not enough room in
271 * freemem, free strings until there is room.
272 */
273static struct string *
274tty3270_alloc_string(struct tty3270 *tp, size_t size)
275{
276	struct string *s, *n;
277
278	s = alloc_string(&tp->freemem, size);
279	if (s)
280		return s;
281	list_for_each_entry_safe(s, n, &tp->lines, list) {
282		BUG_ON(tp->nr_lines <= tp->view.rows - 2);
283		list_del(&s->list);
284		if (!list_empty(&s->update))
285			list_del(&s->update);
286		tp->nr_lines--;
287		if (free_string(&tp->freemem, s) >= size)
288			break;
289	}
290	s = alloc_string(&tp->freemem, size);
291	BUG_ON(!s);
292	if (tp->nr_up != 0 &&
293	    tp->nr_up + tp->view.rows - 2 >= tp->nr_lines) {
294		tp->nr_up = tp->nr_lines - tp->view.rows + 2;
295		tty3270_rebuild_update(tp);
296		tty3270_update_status(tp);
297	}
298	return s;
299}
300
301/*
302 * Add an empty line to the list.
303 */
304static void
305tty3270_blank_line(struct tty3270 *tp)
306{
307	static const unsigned char blueprint[] =
308		{ TO_SBA, 0, 0, TO_SA, TAT_EXTHI, TAX_RESET,
309		  TO_SA, TAT_COLOR, TAC_RESET, TO_RA, 0, 0, 0 };
310	struct string *s;
311
312	s = tty3270_alloc_string(tp, sizeof(blueprint));
313	memcpy(s->string, blueprint, sizeof(blueprint));
314	s->len = sizeof(blueprint);
315	list_add_tail(&s->list, &tp->lines);
316	tp->nr_lines++;
317	if (tp->nr_up != 0)
318		tp->nr_up++;
319}
320
321/*
322 * Write request completion callback.
323 */
324static void
325tty3270_write_callback(struct raw3270_request *rq, void *data)
326{
327	struct tty3270 *tp = container_of(rq->view, struct tty3270, view);
328
329	if (rq->rc != 0) {
330		/* Write wasn't successful. Refresh all. */
331		tp->update_flags = TTY_UPDATE_ALL;
332		tty3270_set_timer(tp, 1);
333	}
334	raw3270_request_reset(rq);
335	xchg(&tp->write, rq);
336}
337
338/*
339 * Update 3270 display.
340 */
341static void
342tty3270_update(struct tty3270 *tp)
343{
344	static char invalid_sba[2] = { 0xff, 0xff };
345	struct raw3270_request *wrq;
346	unsigned long updated;
347	struct string *s, *n;
348	char *sba, *str;
349	int rc, len;
350
351	wrq = xchg(&tp->write, 0);
352	if (!wrq) {
353		tty3270_set_timer(tp, 1);
354		return;
355	}
356
357	spin_lock(&tp->view.lock);
358	updated = 0;
359	if (tp->update_flags & TTY_UPDATE_ALL) {
360		tty3270_rebuild_update(tp);
361		tty3270_update_status(tp);
362		tp->update_flags = TTY_UPDATE_ERASE | TTY_UPDATE_LIST |
363			TTY_UPDATE_INPUT | TTY_UPDATE_STATUS;
364	}
365	if (tp->update_flags & TTY_UPDATE_ERASE) {
366		/* Use erase write alternate to erase display. */
367		raw3270_request_set_cmd(wrq, TC_EWRITEA);
368		updated |= TTY_UPDATE_ERASE;
369	} else
370		raw3270_request_set_cmd(wrq, TC_WRITE);
371
372	raw3270_request_add_data(wrq, &tp->wcc, 1);
373	tp->wcc = TW_NONE;
374
375	/*
376	 * Update status line.
377	 */
378	if (tp->update_flags & TTY_UPDATE_STATUS)
379		if (raw3270_request_add_data(wrq, tp->status->string,
380					     tp->status->len) == 0)
381			updated |= TTY_UPDATE_STATUS;
382
383	/*
384	 * Write input line.
385	 */
386	if (tp->update_flags & TTY_UPDATE_INPUT)
387		if (raw3270_request_add_data(wrq, tp->prompt->string,
388					     tp->prompt->len) == 0)
389			updated |= TTY_UPDATE_INPUT;
390
391	sba = invalid_sba;
392
393	if (tp->update_flags & TTY_UPDATE_LIST) {
394		/* Write strings in the update list to the screen. */
395		list_for_each_entry_safe(s, n, &tp->update, update) {
396			str = s->string;
397			len = s->len;
398			/*
399			 * Skip TO_SBA at the start of the string if the
400			 * last output position matches the start address
401			 * of this line.
402			 */
403			if (s->string[1] == sba[0] && s->string[2] == sba[1])
404				str += 3, len -= 3;
405			if (raw3270_request_add_data(wrq, str, len) != 0)
406				break;
407			list_del_init(&s->update);
408			sba = s->string + s->len - 3;
409		}
410		if (list_empty(&tp->update))
411			updated |= TTY_UPDATE_LIST;
412	}
413	wrq->callback = tty3270_write_callback;
414	rc = raw3270_start(&tp->view, wrq);
415	if (rc == 0) {
416		tp->update_flags &= ~updated;
417		if (tp->update_flags)
418			tty3270_set_timer(tp, 1);
419	} else {
420		raw3270_request_reset(wrq);
421		xchg(&tp->write, wrq);
422	}
423	spin_unlock(&tp->view.lock);
424}
425
426/*
427 * Command recalling.
428 */
429static void
430tty3270_rcl_add(struct tty3270 *tp, char *input, int len)
431{
432	struct string *s;
433
434	tp->rcl_walk = NULL;
435	if (len <= 0)
436		return;
437	if (tp->rcl_nr >= tp->rcl_max) {
438		s = list_entry(tp->rcl_lines.next, struct string, list);
439		list_del(&s->list);
440		free_string(&tp->freemem, s);
441		tp->rcl_nr--;
442	}
443	s = tty3270_alloc_string(tp, len);
444	memcpy(s->string, input, len);
445	list_add_tail(&s->list, &tp->rcl_lines);
446	tp->rcl_nr++;
447}
448
449static void
450tty3270_rcl_backward(struct kbd_data *kbd)
451{
452	struct tty3270 *tp = container_of(kbd->port, struct tty3270, port);
453	struct string *s;
454
455	spin_lock_bh(&tp->view.lock);
456	if (tp->inattr == TF_INPUT) {
457		if (tp->rcl_walk && tp->rcl_walk->prev != &tp->rcl_lines)
458			tp->rcl_walk = tp->rcl_walk->prev;
459		else if (!list_empty(&tp->rcl_lines))
460			tp->rcl_walk = tp->rcl_lines.prev;
461		s = tp->rcl_walk ?
462			list_entry(tp->rcl_walk, struct string, list) : NULL;
463		if (tp->rcl_walk) {
464			s = list_entry(tp->rcl_walk, struct string, list);
465			tty3270_update_prompt(tp, s->string, s->len);
466		} else
467			tty3270_update_prompt(tp, NULL, 0);
468		tty3270_set_timer(tp, 1);
469	}
470	spin_unlock_bh(&tp->view.lock);
471}
472
473/*
474 * Deactivate tty view.
475 */
476static void
477tty3270_exit_tty(struct kbd_data *kbd)
478{
479	struct tty3270 *tp = container_of(kbd->port, struct tty3270, port);
480
481	raw3270_deactivate_view(&tp->view);
482}
483
484/*
485 * Scroll forward in history.
486 */
487static void
488tty3270_scroll_forward(struct kbd_data *kbd)
489{
490	struct tty3270 *tp = container_of(kbd->port, struct tty3270, port);
491	int nr_up;
492
493	spin_lock_bh(&tp->view.lock);
494	nr_up = tp->nr_up - tp->view.rows + 2;
495	if (nr_up < 0)
496		nr_up = 0;
497	if (nr_up != tp->nr_up) {
498		tp->nr_up = nr_up;
499		tty3270_rebuild_update(tp);
500		tty3270_update_status(tp);
501		tty3270_set_timer(tp, 1);
502	}
503	spin_unlock_bh(&tp->view.lock);
504}
505
506/*
507 * Scroll backward in history.
508 */
509static void
510tty3270_scroll_backward(struct kbd_data *kbd)
511{
512	struct tty3270 *tp = container_of(kbd->port, struct tty3270, port);
513	int nr_up;
514
515	spin_lock_bh(&tp->view.lock);
516	nr_up = tp->nr_up + tp->view.rows - 2;
517	if (nr_up + tp->view.rows - 2 > tp->nr_lines)
518		nr_up = tp->nr_lines - tp->view.rows + 2;
519	if (nr_up != tp->nr_up) {
520		tp->nr_up = nr_up;
521		tty3270_rebuild_update(tp);
522		tty3270_update_status(tp);
523		tty3270_set_timer(tp, 1);
524	}
525	spin_unlock_bh(&tp->view.lock);
526}
527
528/*
529 * Pass input line to tty.
530 */
531static void
532tty3270_read_tasklet(struct raw3270_request *rrq)
533{
534	static char kreset_data = TW_KR;
535	struct tty3270 *tp = container_of(rrq->view, struct tty3270, view);
536	char *input;
537	int len;
538
539	spin_lock_bh(&tp->view.lock);
540	/*
541	 * Two AID keys are special: For 0x7d (enter) the input line
542	 * has to be emitted to the tty and for 0x6d the screen
543	 * needs to be redrawn.
544	 */
545	input = NULL;
546	len = 0;
547	if (tp->input->string[0] == 0x7d) {
548		/* Enter: write input to tty. */
549		input = tp->input->string + 6;
550		len = tp->input->len - 6 - rrq->rescnt;
551		if (tp->inattr != TF_INPUTN)
552			tty3270_rcl_add(tp, input, len);
553		if (tp->nr_up > 0) {
554			tp->nr_up = 0;
555			tty3270_rebuild_update(tp);
556			tty3270_update_status(tp);
557		}
558		/* Clear input area. */
559		tty3270_update_prompt(tp, NULL, 0);
560		tty3270_set_timer(tp, 1);
561	} else if (tp->input->string[0] == 0x6d) {
562		/* Display has been cleared. Redraw. */
563		tp->update_flags = TTY_UPDATE_ALL;
564		tty3270_set_timer(tp, 1);
565	}
566	spin_unlock_bh(&tp->view.lock);
567
568	/* Start keyboard reset command. */
569	raw3270_request_reset(tp->kreset);
570	raw3270_request_set_cmd(tp->kreset, TC_WRITE);
571	raw3270_request_add_data(tp->kreset, &kreset_data, 1);
572	raw3270_start(&tp->view, tp->kreset);
573
574	while (len-- > 0)
575		kbd_keycode(tp->kbd, *input++);
576	/* Emit keycode for AID byte. */
577	kbd_keycode(tp->kbd, 256 + tp->input->string[0]);
578
579	raw3270_request_reset(rrq);
580	xchg(&tp->read, rrq);
581	raw3270_put_view(&tp->view);
582}
583
584/*
585 * Read request completion callback.
586 */
587static void
588tty3270_read_callback(struct raw3270_request *rq, void *data)
589{
590	struct tty3270 *tp = container_of(rq->view, struct tty3270, view);
591	raw3270_get_view(rq->view);
592	/* Schedule tasklet to pass input to tty. */
593	tasklet_schedule(&tp->readlet);
594}
595
596/*
597 * Issue a read request. Call with device lock.
598 */
599static void
600tty3270_issue_read(struct tty3270 *tp, int lock)
601{
602	struct raw3270_request *rrq;
603	int rc;
604
605	rrq = xchg(&tp->read, 0);
606	if (!rrq)
607		/* Read already scheduled. */
608		return;
609	rrq->callback = tty3270_read_callback;
610	rrq->callback_data = tp;
611	raw3270_request_set_cmd(rrq, TC_READMOD);
612	raw3270_request_set_data(rrq, tp->input->string, tp->input->len);
613	/* Issue the read modified request. */
614	if (lock) {
615		rc = raw3270_start(&tp->view, rrq);
616	} else
617		rc = raw3270_start_irq(&tp->view, rrq);
618	if (rc) {
619		raw3270_request_reset(rrq);
620		xchg(&tp->read, rrq);
621	}
622}
623
624/*
625 * Switch to the tty view.
626 */
627static int
628tty3270_activate(struct raw3270_view *view)
629{
630	struct tty3270 *tp = container_of(view, struct tty3270, view);
631
632	tp->update_flags = TTY_UPDATE_ALL;
633	tty3270_set_timer(tp, 1);
634	return 0;
635}
636
637static void
638tty3270_deactivate(struct raw3270_view *view)
639{
640	struct tty3270 *tp = container_of(view, struct tty3270, view);
641
642	del_timer(&tp->timer);
643}
644
645static int
646tty3270_irq(struct tty3270 *tp, struct raw3270_request *rq, struct irb *irb)
647{
648	/* Handle ATTN. Schedule tasklet to read aid. */
649	if (irb->scsw.cmd.dstat & DEV_STAT_ATTENTION) {
650		if (!tp->throttle)
651			tty3270_issue_read(tp, 0);
652		else
653			tp->attn = 1;
654	}
655
656	if (rq) {
657		if (irb->scsw.cmd.dstat & DEV_STAT_UNIT_CHECK)
658			rq->rc = -EIO;
659		else
660			/* Normal end. Copy residual count. */
661			rq->rescnt = irb->scsw.cmd.count;
662	}
663	return RAW3270_IO_DONE;
664}
665
666/*
667 * Allocate tty3270 structure.
668 */
669static struct tty3270 *
670tty3270_alloc_view(void)
671{
672	struct tty3270 *tp;
673	int pages;
674
675	tp = kzalloc(sizeof(struct tty3270), GFP_KERNEL);
676	if (!tp)
677		goto out_err;
678	tp->freemem_pages =
679		kmalloc(sizeof(void *) * TTY3270_STRING_PAGES, GFP_KERNEL);
680	if (!tp->freemem_pages)
681		goto out_tp;
682	INIT_LIST_HEAD(&tp->freemem);
683	INIT_LIST_HEAD(&tp->lines);
684	INIT_LIST_HEAD(&tp->update);
685	INIT_LIST_HEAD(&tp->rcl_lines);
686	tp->rcl_max = 20;
687
688	for (pages = 0; pages < TTY3270_STRING_PAGES; pages++) {
689		tp->freemem_pages[pages] = (void *)
690			__get_free_pages(GFP_KERNEL|GFP_DMA, 0);
691		if (!tp->freemem_pages[pages])
692			goto out_pages;
693		add_string_memory(&tp->freemem,
694				  tp->freemem_pages[pages], PAGE_SIZE);
695	}
696	tp->write = raw3270_request_alloc(TTY3270_OUTPUT_BUFFER_SIZE);
697	if (IS_ERR(tp->write))
698		goto out_pages;
699	tp->read = raw3270_request_alloc(0);
700	if (IS_ERR(tp->read))
701		goto out_write;
702	tp->kreset = raw3270_request_alloc(1);
703	if (IS_ERR(tp->kreset))
704		goto out_read;
705	tp->kbd = kbd_alloc();
706	if (!tp->kbd)
707		goto out_reset;
708
709	tty_port_init(&tp->port);
710	setup_timer(&tp->timer, (void (*)(unsigned long)) tty3270_update,
711		    (unsigned long) tp);
712	tasklet_init(&tp->readlet,
713		     (void (*)(unsigned long)) tty3270_read_tasklet,
714		     (unsigned long) tp->read);
715	INIT_WORK(&tp->resize_work, tty3270_resize_work);
716
717	return tp;
718
719out_reset:
720	raw3270_request_free(tp->kreset);
721out_read:
722	raw3270_request_free(tp->read);
723out_write:
724	raw3270_request_free(tp->write);
725out_pages:
726	while (pages--)
727		free_pages((unsigned long) tp->freemem_pages[pages], 0);
728	kfree(tp->freemem_pages);
729	tty_port_destroy(&tp->port);
730out_tp:
731	kfree(tp);
732out_err:
733	return ERR_PTR(-ENOMEM);
734}
735
736/*
737 * Free tty3270 structure.
738 */
739static void
740tty3270_free_view(struct tty3270 *tp)
741{
742	int pages;
743
744	kbd_free(tp->kbd);
745	raw3270_request_free(tp->kreset);
746	raw3270_request_free(tp->read);
747	raw3270_request_free(tp->write);
748	for (pages = 0; pages < TTY3270_STRING_PAGES; pages++)
749		free_pages((unsigned long) tp->freemem_pages[pages], 0);
750	kfree(tp->freemem_pages);
751	tty_port_destroy(&tp->port);
752	kfree(tp);
753}
754
755/*
756 * Allocate tty3270 screen.
757 */
758static struct tty3270_line *
759tty3270_alloc_screen(unsigned int rows, unsigned int cols)
760{
761	struct tty3270_line *screen;
762	unsigned long size;
763	int lines;
764
765	size = sizeof(struct tty3270_line) * (rows - 2);
766	screen = kzalloc(size, GFP_KERNEL);
767	if (!screen)
768		goto out_err;
769	for (lines = 0; lines < rows - 2; lines++) {
770		size = sizeof(struct tty3270_cell) * cols;
771		screen[lines].cells = kzalloc(size, GFP_KERNEL);
772		if (!screen[lines].cells)
773			goto out_screen;
774	}
775	return screen;
776out_screen:
777	while (lines--)
778		kfree(screen[lines].cells);
779	kfree(screen);
780out_err:
781	return ERR_PTR(-ENOMEM);
782}
783
784/*
785 * Free tty3270 screen.
786 */
787static void
788tty3270_free_screen(struct tty3270_line *screen, unsigned int rows)
789{
790	int lines;
791
792	for (lines = 0; lines < rows - 2; lines++)
793		kfree(screen[lines].cells);
794	kfree(screen);
795}
796
797/*
798 * Resize tty3270 screen
799 */
800static void tty3270_resize_work(struct work_struct *work)
801{
802	struct tty3270 *tp = container_of(work, struct tty3270, resize_work);
803	struct tty3270_line *screen, *oscreen;
804	struct tty_struct *tty;
805	unsigned int orows;
806	struct winsize ws;
807
808	screen = tty3270_alloc_screen(tp->n_rows, tp->n_cols);
809	if (IS_ERR(screen))
810		return;
811	/* Switch to new output size */
812	spin_lock_bh(&tp->view.lock);
813	oscreen = tp->screen;
814	orows = tp->view.rows;
815	tp->view.model = tp->n_model;
816	tp->view.rows = tp->n_rows;
817	tp->view.cols = tp->n_cols;
818	tp->screen = screen;
819	free_string(&tp->freemem, tp->prompt);
820	free_string(&tp->freemem, tp->status);
821	tty3270_create_prompt(tp);
822	tty3270_create_status(tp);
823	tp->nr_up = 0;
824	while (tp->nr_lines < tp->view.rows - 2)
825		tty3270_blank_line(tp);
826	tp->update_flags = TTY_UPDATE_ALL;
827	spin_unlock_bh(&tp->view.lock);
828	tty3270_free_screen(oscreen, orows);
829	tty3270_set_timer(tp, 1);
830	/* Informat tty layer about new size */
831	tty = tty_port_tty_get(&tp->port);
832	if (!tty)
833		return;
834	ws.ws_row = tp->view.rows - 2;
835	ws.ws_col = tp->view.cols;
836	tty_do_resize(tty, &ws);
837}
838
839static void
840tty3270_resize(struct raw3270_view *view, int model, int rows, int cols)
841{
842	struct tty3270 *tp = container_of(view, struct tty3270, view);
843
844	tp->n_model = model;
845	tp->n_rows = rows;
846	tp->n_cols = cols;
847	schedule_work(&tp->resize_work);
848}
849
850/*
851 * Unlink tty3270 data structure from tty.
852 */
853static void
854tty3270_release(struct raw3270_view *view)
855{
856	struct tty3270 *tp = container_of(view, struct tty3270, view);
857	struct tty_struct *tty = tty_port_tty_get(&tp->port);
858
859	if (tty) {
860		tty->driver_data = NULL;
861		tty_port_tty_set(&tp->port, NULL);
862		tty_hangup(tty);
863		raw3270_put_view(&tp->view);
864		tty_kref_put(tty);
865	}
866}
867
868/*
869 * Free tty3270 data structure
870 */
871static void
872tty3270_free(struct raw3270_view *view)
873{
874	struct tty3270 *tp = container_of(view, struct tty3270, view);
875
876	del_timer_sync(&tp->timer);
877	tty3270_free_screen(tp->screen, tp->view.rows);
878	tty3270_free_view(tp);
879}
880
881/*
882 * Delayed freeing of tty3270 views.
883 */
884static void
885tty3270_del_views(void)
886{
887	int i;
888
889	for (i = RAW3270_FIRSTMINOR; i <= tty3270_max_index; i++) {
890		struct raw3270_view *view = raw3270_find_view(&tty3270_fn, i);
891		if (!IS_ERR(view))
892			raw3270_del_view(view);
893	}
894}
895
896static struct raw3270_fn tty3270_fn = {
897	.activate = tty3270_activate,
898	.deactivate = tty3270_deactivate,
899	.intv = (void *) tty3270_irq,
900	.release = tty3270_release,
901	.free = tty3270_free,
902	.resize = tty3270_resize
903};
904
905/*
906 * This routine is called whenever a 3270 tty is opened first time.
907 */
908static int tty3270_install(struct tty_driver *driver, struct tty_struct *tty)
909{
910	struct raw3270_view *view;
911	struct tty3270 *tp;
912	int i, rc;
913
914	/* Check if the tty3270 is already there. */
915	view = raw3270_find_view(&tty3270_fn, tty->index + RAW3270_FIRSTMINOR);
916	if (!IS_ERR(view)) {
917		tp = container_of(view, struct tty3270, view);
918		tty->driver_data = tp;
919		tty->winsize.ws_row = tp->view.rows - 2;
920		tty->winsize.ws_col = tp->view.cols;
921		tp->port.low_latency = 0;
922		/* why to reassign? */
923		tty_port_tty_set(&tp->port, tty);
924		tp->inattr = TF_INPUT;
925		return tty_port_install(&tp->port, driver, tty);
926	}
927	if (tty3270_max_index < tty->index + 1)
928		tty3270_max_index = tty->index + 1;
929
930	/* Allocate tty3270 structure on first open. */
931	tp = tty3270_alloc_view();
932	if (IS_ERR(tp))
933		return PTR_ERR(tp);
934
935	rc = raw3270_add_view(&tp->view, &tty3270_fn,
936			      tty->index + RAW3270_FIRSTMINOR);
937	if (rc) {
938		tty3270_free_view(tp);
939		return rc;
940	}
941
942	tp->screen = tty3270_alloc_screen(tp->view.rows, tp->view.cols);
943	if (IS_ERR(tp->screen)) {
944		rc = PTR_ERR(tp->screen);
945		raw3270_put_view(&tp->view);
946		raw3270_del_view(&tp->view);
947		tty3270_free_view(tp);
948		return rc;
949	}
950
951	tty_port_tty_set(&tp->port, tty);
952	tp->port.low_latency = 0;
953	tty->winsize.ws_row = tp->view.rows - 2;
954	tty->winsize.ws_col = tp->view.cols;
955
956	tty3270_create_prompt(tp);
957	tty3270_create_status(tp);
958	tty3270_update_status(tp);
959
960	/* Create blank line for every line in the tty output area. */
961	for (i = 0; i < tp->view.rows - 2; i++)
962		tty3270_blank_line(tp);
963
964	tp->kbd->port = &tp->port;
965	tp->kbd->fn_handler[KVAL(K_INCRCONSOLE)] = tty3270_exit_tty;
966	tp->kbd->fn_handler[KVAL(K_SCROLLBACK)] = tty3270_scroll_backward;
967	tp->kbd->fn_handler[KVAL(K_SCROLLFORW)] = tty3270_scroll_forward;
968	tp->kbd->fn_handler[KVAL(K_CONS)] = tty3270_rcl_backward;
969	kbd_ascebc(tp->kbd, tp->view.ascebc);
970
971	raw3270_activate_view(&tp->view);
972
973	rc = tty_port_install(&tp->port, driver, tty);
974	if (rc) {
975		raw3270_put_view(&tp->view);
976		return rc;
977	}
978
979	tty->driver_data = tp;
980
981	return 0;
982}
983
984/*
985 * This routine is called whenever a 3270 tty is opened.
986 */
987static int
988tty3270_open(struct tty_struct *tty, struct file *filp)
989{
990	struct tty3270 *tp = tty->driver_data;
991	struct tty_port *port = &tp->port;
992
993	port->count++;
994	tty_port_tty_set(port, tty);
995	return 0;
996}
997
998/*
999 * This routine is called when the 3270 tty is closed. We wait
1000 * for the remaining request to be completed. Then we clean up.
1001 */
1002static void
1003tty3270_close(struct tty_struct *tty, struct file * filp)
1004{
1005	struct tty3270 *tp = tty->driver_data;
1006
1007	if (tty->count > 1)
1008		return;
1009	if (tp) {
1010		tty->driver_data = NULL;
1011		tty_port_tty_set(&tp->port, NULL);
1012	}
1013}
1014
1015static void tty3270_cleanup(struct tty_struct *tty)
1016{
1017	struct tty3270 *tp = tty->driver_data;
1018
1019	if (tp)
1020		raw3270_put_view(&tp->view);
1021}
1022
1023/*
1024 * We always have room.
1025 */
1026static int
1027tty3270_write_room(struct tty_struct *tty)
1028{
1029	return INT_MAX;
1030}
1031
1032/*
1033 * Insert character into the screen at the current position with the
1034 * current color and highlight. This function does NOT do cursor movement.
1035 */
1036static void tty3270_put_character(struct tty3270 *tp, char ch)
1037{
1038	struct tty3270_line *line;
1039	struct tty3270_cell *cell;
1040
1041	line = tp->screen + tp->cy;
1042	if (line->len <= tp->cx) {
1043		while (line->len < tp->cx) {
1044			cell = line->cells + line->len;
1045			cell->character = tp->view.ascebc[' '];
1046			cell->highlight = tp->highlight;
1047			cell->f_color = tp->f_color;
1048			line->len++;
1049		}
1050		line->len++;
1051	}
1052	cell = line->cells + tp->cx;
1053	cell->character = tp->view.ascebc[(unsigned int) ch];
1054	cell->highlight = tp->highlight;
1055	cell->f_color = tp->f_color;
1056}
1057
1058/*
1059 * Convert a tty3270_line to a 3270 data fragment usable for output.
1060 */
1061static void
1062tty3270_convert_line(struct tty3270 *tp, int line_nr)
1063{
1064	struct tty3270_line *line;
1065	struct tty3270_cell *cell;
1066	struct string *s, *n;
1067	unsigned char highlight;
1068	unsigned char f_color;
1069	char *cp;
1070	int flen, i;
1071
1072	/* Determine how long the fragment will be. */
1073	flen = 3;		/* Prefix (TO_SBA). */
1074	line = tp->screen + line_nr;
1075	flen += line->len;
1076	highlight = TAX_RESET;
1077	f_color = TAC_RESET;
1078	for (i = 0, cell = line->cells; i < line->len; i++, cell++) {
1079		if (cell->highlight != highlight) {
1080			flen += 3;	/* TO_SA to switch highlight. */
1081			highlight = cell->highlight;
1082		}
1083		if (cell->f_color != f_color) {
1084			flen += 3;	/* TO_SA to switch color. */
1085			f_color = cell->f_color;
1086		}
1087	}
1088	if (highlight != TAX_RESET)
1089		flen += 3;	/* TO_SA to reset hightlight. */
1090	if (f_color != TAC_RESET)
1091		flen += 3;	/* TO_SA to reset color. */
1092	if (line->len < tp->view.cols)
1093		flen += 4;	/* Postfix (TO_RA). */
1094
1095	/* Find the line in the list. */
1096	i = tp->view.rows - 2 - line_nr;
1097	list_for_each_entry_reverse(s, &tp->lines, list)
1098		if (--i <= 0)
1099			break;
1100	/*
1101	 * Check if the line needs to get reallocated.
1102	 */
1103	if (s->len != flen) {
1104		/* Reallocate string. */
1105		n = tty3270_alloc_string(tp, flen);
1106		list_add(&n->list, &s->list);
1107		list_del_init(&s->list);
1108		if (!list_empty(&s->update))
1109			list_del_init(&s->update);
1110		free_string(&tp->freemem, s);
1111		s = n;
1112	}
1113
1114	/* Write 3270 data fragment. */
1115	cp = s->string;
1116	*cp++ = TO_SBA;
1117	*cp++ = 0;
1118	*cp++ = 0;
1119
1120	highlight = TAX_RESET;
1121	f_color = TAC_RESET;
1122	for (i = 0, cell = line->cells; i < line->len; i++, cell++) {
1123		if (cell->highlight != highlight) {
1124			*cp++ = TO_SA;
1125			*cp++ = TAT_EXTHI;
1126			*cp++ = cell->highlight;
1127			highlight = cell->highlight;
1128		}
1129		if (cell->f_color != f_color) {
1130			*cp++ = TO_SA;
1131			*cp++ = TAT_COLOR;
1132			*cp++ = cell->f_color;
1133			f_color = cell->f_color;
1134		}
1135		*cp++ = cell->character;
1136	}
1137	if (highlight != TAX_RESET) {
1138		*cp++ = TO_SA;
1139		*cp++ = TAT_EXTHI;
1140		*cp++ = TAX_RESET;
1141	}
1142	if (f_color != TAC_RESET) {
1143		*cp++ = TO_SA;
1144		*cp++ = TAT_COLOR;
1145		*cp++ = TAC_RESET;
1146	}
1147	if (line->len < tp->view.cols) {
1148		*cp++ = TO_RA;
1149		*cp++ = 0;
1150		*cp++ = 0;
1151		*cp++ = 0;
1152	}
1153
1154	if (tp->nr_up + line_nr < tp->view.rows - 2) {
1155		/* Line is currently visible on screen. */
1156		tty3270_update_string(tp, s, line_nr);
1157		/* Add line to update list. */
1158		if (list_empty(&s->update)) {
1159			list_add_tail(&s->update, &tp->update);
1160			tp->update_flags |= TTY_UPDATE_LIST;
1161		}
1162	}
1163}
1164
1165/*
1166 * Do carriage return.
1167 */
1168static void
1169tty3270_cr(struct tty3270 *tp)
1170{
1171	tp->cx = 0;
1172}
1173
1174/*
1175 * Do line feed.
1176 */
1177static void
1178tty3270_lf(struct tty3270 *tp)
1179{
1180	struct tty3270_line temp;
1181	int i;
1182
1183	tty3270_convert_line(tp, tp->cy);
1184	if (tp->cy < tp->view.rows - 3) {
1185		tp->cy++;
1186		return;
1187	}
1188	/* Last line just filled up. Add new, blank line. */
1189	tty3270_blank_line(tp);
1190	temp = tp->screen[0];
1191	temp.len = 0;
1192	for (i = 0; i < tp->view.rows - 3; i++)
1193		tp->screen[i] = tp->screen[i+1];
1194	tp->screen[tp->view.rows - 3] = temp;
1195	tty3270_rebuild_update(tp);
1196}
1197
1198static void
1199tty3270_ri(struct tty3270 *tp)
1200{
1201	if (tp->cy > 0) {
1202	    tty3270_convert_line(tp, tp->cy);
1203	    tp->cy--;
1204	}
1205}
1206
1207/*
1208 * Insert characters at current position.
1209 */
1210static void
1211tty3270_insert_characters(struct tty3270 *tp, int n)
1212{
1213	struct tty3270_line *line;
1214	int k;
1215
1216	line = tp->screen + tp->cy;
1217	while (line->len < tp->cx) {
1218		line->cells[line->len].character = tp->view.ascebc[' '];
1219		line->cells[line->len].highlight = TAX_RESET;
1220		line->cells[line->len].f_color = TAC_RESET;
1221		line->len++;
1222	}
1223	if (n > tp->view.cols - tp->cx)
1224		n = tp->view.cols - tp->cx;
1225	k = min_t(int, line->len - tp->cx, tp->view.cols - tp->cx - n);
1226	while (k--)
1227		line->cells[tp->cx + n + k] = line->cells[tp->cx + k];
1228	line->len += n;
1229	if (line->len > tp->view.cols)
1230		line->len = tp->view.cols;
1231	while (n-- > 0) {
1232		line->cells[tp->cx + n].character = tp->view.ascebc[' '];
1233		line->cells[tp->cx + n].highlight = tp->highlight;
1234		line->cells[tp->cx + n].f_color = tp->f_color;
1235	}
1236}
1237
1238/*
1239 * Delete characters at current position.
1240 */
1241static void
1242tty3270_delete_characters(struct tty3270 *tp, int n)
1243{
1244	struct tty3270_line *line;
1245	int i;
1246
1247	line = tp->screen + tp->cy;
1248	if (line->len <= tp->cx)
1249		return;
1250	if (line->len - tp->cx <= n) {
1251		line->len = tp->cx;
1252		return;
1253	}
1254	for (i = tp->cx; i + n < line->len; i++)
1255		line->cells[i] = line->cells[i + n];
1256	line->len -= n;
1257}
1258
1259/*
1260 * Erase characters at current position.
1261 */
1262static void
1263tty3270_erase_characters(struct tty3270 *tp, int n)
1264{
1265	struct tty3270_line *line;
1266	struct tty3270_cell *cell;
1267
1268	line = tp->screen + tp->cy;
1269	while (line->len > tp->cx && n-- > 0) {
1270		cell = line->cells + tp->cx++;
1271		cell->character = ' ';
1272		cell->highlight = TAX_RESET;
1273		cell->f_color = TAC_RESET;
1274	}
1275	tp->cx += n;
1276	tp->cx = min_t(int, tp->cx, tp->view.cols - 1);
1277}
1278
1279/*
1280 * Erase line, 3 different cases:
1281 *  Esc [ 0 K	Erase from current position to end of line inclusive
1282 *  Esc [ 1 K	Erase from beginning of line to current position inclusive
1283 *  Esc [ 2 K	Erase entire line (without moving cursor)
1284 */
1285static void
1286tty3270_erase_line(struct tty3270 *tp, int mode)
1287{
1288	struct tty3270_line *line;
1289	struct tty3270_cell *cell;
1290	int i;
1291
1292	line = tp->screen + tp->cy;
1293	if (mode == 0)
1294		line->len = tp->cx;
1295	else if (mode == 1) {
1296		for (i = 0; i < tp->cx; i++) {
1297			cell = line->cells + i;
1298			cell->character = ' ';
1299			cell->highlight = TAX_RESET;
1300			cell->f_color = TAC_RESET;
1301		}
1302		if (line->len <= tp->cx)
1303			line->len = tp->cx + 1;
1304	} else if (mode == 2)
1305		line->len = 0;
1306	tty3270_convert_line(tp, tp->cy);
1307}
1308
1309/*
1310 * Erase display, 3 different cases:
1311 *  Esc [ 0 J	Erase from current position to bottom of screen inclusive
1312 *  Esc [ 1 J	Erase from top of screen to current position inclusive
1313 *  Esc [ 2 J	Erase entire screen (without moving the cursor)
1314 */
1315static void
1316tty3270_erase_display(struct tty3270 *tp, int mode)
1317{
1318	int i;
1319
1320	if (mode == 0) {
1321		tty3270_erase_line(tp, 0);
1322		for (i = tp->cy + 1; i < tp->view.rows - 2; i++) {
1323			tp->screen[i].len = 0;
1324			tty3270_convert_line(tp, i);
1325		}
1326	} else if (mode == 1) {
1327		for (i = 0; i < tp->cy; i++) {
1328			tp->screen[i].len = 0;
1329			tty3270_convert_line(tp, i);
1330		}
1331		tty3270_erase_line(tp, 1);
1332	} else if (mode == 2) {
1333		for (i = 0; i < tp->view.rows - 2; i++) {
1334			tp->screen[i].len = 0;
1335			tty3270_convert_line(tp, i);
1336		}
1337	}
1338	tty3270_rebuild_update(tp);
1339}
1340
1341/*
1342 * Set attributes found in an escape sequence.
1343 *  Esc [ <attr> ; <attr> ; ... m
1344 */
1345static void
1346tty3270_set_attributes(struct tty3270 *tp)
1347{
1348	static unsigned char f_colors[] = {
1349		TAC_DEFAULT, TAC_RED, TAC_GREEN, TAC_YELLOW, TAC_BLUE,
1350		TAC_PINK, TAC_TURQ, TAC_WHITE, 0, TAC_DEFAULT
1351	};
1352	int i, attr;
1353
1354	for (i = 0; i <= tp->esc_npar; i++) {
1355		attr = tp->esc_par[i];
1356		switch (attr) {
1357		case 0:		/* Reset */
1358			tp->highlight = TAX_RESET;
1359			tp->f_color = TAC_RESET;
1360			break;
1361		/* Highlight. */
1362		case 4:		/* Start underlining. */
1363			tp->highlight = TAX_UNDER;
1364			break;
1365		case 5:		/* Start blink. */
1366			tp->highlight = TAX_BLINK;
1367			break;
1368		case 7:		/* Start reverse. */
1369			tp->highlight = TAX_REVER;
1370			break;
1371		case 24:	/* End underlining */
1372			if (tp->highlight == TAX_UNDER)
1373				tp->highlight = TAX_RESET;
1374			break;
1375		case 25:	/* End blink. */
1376			if (tp->highlight == TAX_BLINK)
1377				tp->highlight = TAX_RESET;
1378			break;
1379		case 27:	/* End reverse. */
1380			if (tp->highlight == TAX_REVER)
1381				tp->highlight = TAX_RESET;
1382			break;
1383		/* Foreground color. */
1384		case 30:	/* Black */
1385		case 31:	/* Red */
1386		case 32:	/* Green */
1387		case 33:	/* Yellow */
1388		case 34:	/* Blue */
1389		case 35:	/* Magenta */
1390		case 36:	/* Cyan */
1391		case 37:	/* White */
1392		case 39:	/* Black */
1393			tp->f_color = f_colors[attr - 30];
1394			break;
1395		}
1396	}
1397}
1398
1399static inline int
1400tty3270_getpar(struct tty3270 *tp, int ix)
1401{
1402	return (tp->esc_par[ix] > 0) ? tp->esc_par[ix] : 1;
1403}
1404
1405static void
1406tty3270_goto_xy(struct tty3270 *tp, int cx, int cy)
1407{
1408	int max_cx = max(0, cx);
1409	int max_cy = max(0, cy);
1410
1411	tp->cx = min_t(int, tp->view.cols - 1, max_cx);
1412	cy = min_t(int, tp->view.rows - 3, max_cy);
1413	if (cy != tp->cy) {
1414		tty3270_convert_line(tp, tp->cy);
1415		tp->cy = cy;
1416	}
1417}
1418
1419/*
1420 * Process escape sequences. Known sequences:
1421 *  Esc 7			Save Cursor Position
1422 *  Esc 8			Restore Cursor Position
1423 *  Esc [ Pn ; Pn ; .. m	Set attributes
1424 *  Esc [ Pn ; Pn H		Cursor Position
1425 *  Esc [ Pn ; Pn f		Cursor Position
1426 *  Esc [ Pn A			Cursor Up
1427 *  Esc [ Pn B			Cursor Down
1428 *  Esc [ Pn C			Cursor Forward
1429 *  Esc [ Pn D			Cursor Backward
1430 *  Esc [ Pn G			Cursor Horizontal Absolute
1431 *  Esc [ Pn X			Erase Characters
1432 *  Esc [ Ps J			Erase in Display
1433 *  Esc [ Ps K			Erase in Line
1434 * // FIXME: add all the new ones.
1435 *
1436 *  Pn is a numeric parameter, a string of zero or more decimal digits.
1437 *  Ps is a selective parameter.
1438 */
1439static void
1440tty3270_escape_sequence(struct tty3270 *tp, char ch)
1441{
1442	enum { ESnormal, ESesc, ESsquare, ESgetpars };
1443
1444	if (tp->esc_state == ESnormal) {
1445		if (ch == 0x1b)
1446			/* Starting new escape sequence. */
1447			tp->esc_state = ESesc;
1448		return;
1449	}
1450	if (tp->esc_state == ESesc) {
1451		tp->esc_state = ESnormal;
1452		switch (ch) {
1453		case '[':
1454			tp->esc_state = ESsquare;
1455			break;
1456		case 'E':
1457			tty3270_cr(tp);
1458			tty3270_lf(tp);
1459			break;
1460		case 'M':
1461			tty3270_ri(tp);
1462			break;
1463		case 'D':
1464			tty3270_lf(tp);
1465			break;
1466		case 'Z':		/* Respond ID. */
1467			kbd_puts_queue(&tp->port, "\033[?6c");
1468			break;
1469		case '7':		/* Save cursor position. */
1470			tp->saved_cx = tp->cx;
1471			tp->saved_cy = tp->cy;
1472			tp->saved_highlight = tp->highlight;
1473			tp->saved_f_color = tp->f_color;
1474			break;
1475		case '8':		/* Restore cursor position. */
1476			tty3270_convert_line(tp, tp->cy);
1477			tty3270_goto_xy(tp, tp->saved_cx, tp->saved_cy);
1478			tp->highlight = tp->saved_highlight;
1479			tp->f_color = tp->saved_f_color;
1480			break;
1481		case 'c':		/* Reset terminal. */
1482			tp->cx = tp->saved_cx = 0;
1483			tp->cy = tp->saved_cy = 0;
1484			tp->highlight = tp->saved_highlight = TAX_RESET;
1485			tp->f_color = tp->saved_f_color = TAC_RESET;
1486			tty3270_erase_display(tp, 2);
1487			break;
1488		}
1489		return;
1490	}
1491	if (tp->esc_state == ESsquare) {
1492		tp->esc_state = ESgetpars;
1493		memset(tp->esc_par, 0, sizeof(tp->esc_par));
1494		tp->esc_npar = 0;
1495		tp->esc_ques = (ch == '?');
1496		if (tp->esc_ques)
1497			return;
1498	}
1499	if (tp->esc_state == ESgetpars) {
1500		if (ch == ';' && tp->esc_npar < ESCAPE_NPAR - 1) {
1501			tp->esc_npar++;
1502			return;
1503		}
1504		if (ch >= '0' && ch <= '9') {
1505			tp->esc_par[tp->esc_npar] *= 10;
1506			tp->esc_par[tp->esc_npar] += ch - '0';
1507			return;
1508		}
1509	}
1510	tp->esc_state = ESnormal;
1511	if (ch == 'n' && !tp->esc_ques) {
1512		if (tp->esc_par[0] == 5)		/* Status report. */
1513			kbd_puts_queue(&tp->port, "\033[0n");
1514		else if (tp->esc_par[0] == 6) {	/* Cursor report. */
1515			char buf[40];
1516			sprintf(buf, "\033[%d;%dR", tp->cy + 1, tp->cx + 1);
1517			kbd_puts_queue(&tp->port, buf);
1518		}
1519		return;
1520	}
1521	if (tp->esc_ques)
1522		return;
1523	switch (ch) {
1524	case 'm':
1525		tty3270_set_attributes(tp);
1526		break;
1527	case 'H':	/* Set cursor position. */
1528	case 'f':
1529		tty3270_goto_xy(tp, tty3270_getpar(tp, 1) - 1,
1530				tty3270_getpar(tp, 0) - 1);
1531		break;
1532	case 'd':	/* Set y position. */
1533		tty3270_goto_xy(tp, tp->cx, tty3270_getpar(tp, 0) - 1);
1534		break;
1535	case 'A':	/* Cursor up. */
1536	case 'F':
1537		tty3270_goto_xy(tp, tp->cx, tp->cy - tty3270_getpar(tp, 0));
1538		break;
1539	case 'B':	/* Cursor down. */
1540	case 'e':
1541	case 'E':
1542		tty3270_goto_xy(tp, tp->cx, tp->cy + tty3270_getpar(tp, 0));
1543		break;
1544	case 'C':	/* Cursor forward. */
1545	case 'a':
1546		tty3270_goto_xy(tp, tp->cx + tty3270_getpar(tp, 0), tp->cy);
1547		break;
1548	case 'D':	/* Cursor backward. */
1549		tty3270_goto_xy(tp, tp->cx - tty3270_getpar(tp, 0), tp->cy);
1550		break;
1551	case 'G':	/* Set x position. */
1552	case '`':
1553		tty3270_goto_xy(tp, tty3270_getpar(tp, 0), tp->cy);
1554		break;
1555	case 'X':	/* Erase Characters. */
1556		tty3270_erase_characters(tp, tty3270_getpar(tp, 0));
1557		break;
1558	case 'J':	/* Erase display. */
1559		tty3270_erase_display(tp, tp->esc_par[0]);
1560		break;
1561	case 'K':	/* Erase line. */
1562		tty3270_erase_line(tp, tp->esc_par[0]);
1563		break;
1564	case 'P':	/* Delete characters. */
1565		tty3270_delete_characters(tp, tty3270_getpar(tp, 0));
1566		break;
1567	case '@':	/* Insert characters. */
1568		tty3270_insert_characters(tp, tty3270_getpar(tp, 0));
1569		break;
1570	case 's':	/* Save cursor position. */
1571		tp->saved_cx = tp->cx;
1572		tp->saved_cy = tp->cy;
1573		tp->saved_highlight = tp->highlight;
1574		tp->saved_f_color = tp->f_color;
1575		break;
1576	case 'u':	/* Restore cursor position. */
1577		tty3270_convert_line(tp, tp->cy);
1578		tty3270_goto_xy(tp, tp->saved_cx, tp->saved_cy);
1579		tp->highlight = tp->saved_highlight;
1580		tp->f_color = tp->saved_f_color;
1581		break;
1582	}
1583}
1584
1585/*
1586 * String write routine for 3270 ttys
1587 */
1588static void
1589tty3270_do_write(struct tty3270 *tp, struct tty_struct *tty,
1590		const unsigned char *buf, int count)
1591{
1592	int i_msg, i;
1593
1594	spin_lock_bh(&tp->view.lock);
1595	for (i_msg = 0; !tty->stopped && i_msg < count; i_msg++) {
1596		if (tp->esc_state != 0) {
1597			/* Continue escape sequence. */
1598			tty3270_escape_sequence(tp, buf[i_msg]);
1599			continue;
1600		}
1601
1602		switch (buf[i_msg]) {
1603		case 0x07:		/* '\a' -- Alarm */
1604			tp->wcc |= TW_PLUSALARM;
1605			break;
1606		case 0x08:		/* Backspace. */
1607			if (tp->cx > 0) {
1608				tp->cx--;
1609				tty3270_put_character(tp, ' ');
1610			}
1611			break;
1612		case 0x09:		/* '\t' -- Tabulate */
1613			for (i = tp->cx % 8; i < 8; i++) {
1614				if (tp->cx >= tp->view.cols) {
1615					tty3270_cr(tp);
1616					tty3270_lf(tp);
1617					break;
1618				}
1619				tty3270_put_character(tp, ' ');
1620				tp->cx++;
1621			}
1622			break;
1623		case 0x0a:		/* '\n' -- New Line */
1624			tty3270_cr(tp);
1625			tty3270_lf(tp);
1626			break;
1627		case 0x0c:		/* '\f' -- Form Feed */
1628			tty3270_erase_display(tp, 2);
1629			tp->cx = tp->cy = 0;
1630			break;
1631		case 0x0d:		/* '\r' -- Carriage Return */
1632			tp->cx = 0;
1633			break;
1634		case 0x0f:		/* SuSE "exit alternate mode" */
1635			break;
1636		case 0x1b:		/* Start escape sequence. */
1637			tty3270_escape_sequence(tp, buf[i_msg]);
1638			break;
1639		default:		/* Insert normal character. */
1640			if (tp->cx >= tp->view.cols) {
1641				tty3270_cr(tp);
1642				tty3270_lf(tp);
1643			}
1644			tty3270_put_character(tp, buf[i_msg]);
1645			tp->cx++;
1646			break;
1647		}
1648	}
1649	/* Convert current line to 3270 data fragment. */
1650	tty3270_convert_line(tp, tp->cy);
1651
1652	/* Setup timer to update display after 1/10 second */
1653	if (!timer_pending(&tp->timer))
1654		tty3270_set_timer(tp, HZ/10);
1655
1656	spin_unlock_bh(&tp->view.lock);
1657}
1658
1659/*
1660 * String write routine for 3270 ttys
1661 */
1662static int
1663tty3270_write(struct tty_struct * tty,
1664	      const unsigned char *buf, int count)
1665{
1666	struct tty3270 *tp;
1667
1668	tp = tty->driver_data;
1669	if (!tp)
1670		return 0;
1671	if (tp->char_count > 0) {
1672		tty3270_do_write(tp, tty, tp->char_buf, tp->char_count);
1673		tp->char_count = 0;
1674	}
1675	tty3270_do_write(tp, tty, buf, count);
1676	return count;
1677}
1678
1679/*
1680 * Put single characters to the ttys character buffer
1681 */
1682static int tty3270_put_char(struct tty_struct *tty, unsigned char ch)
1683{
1684	struct tty3270 *tp;
1685
1686	tp = tty->driver_data;
1687	if (!tp || tp->char_count >= TTY3270_CHAR_BUF_SIZE)
1688		return 0;
1689	tp->char_buf[tp->char_count++] = ch;
1690	return 1;
1691}
1692
1693/*
1694 * Flush all characters from the ttys characeter buffer put there
1695 * by tty3270_put_char.
1696 */
1697static void
1698tty3270_flush_chars(struct tty_struct *tty)
1699{
1700	struct tty3270 *tp;
1701
1702	tp = tty->driver_data;
1703	if (!tp)
1704		return;
1705	if (tp->char_count > 0) {
1706		tty3270_do_write(tp, tty, tp->char_buf, tp->char_count);
1707		tp->char_count = 0;
1708	}
1709}
1710
1711/*
1712 * Returns the number of characters in the output buffer. This is
1713 * used in tty_wait_until_sent to wait until all characters have
1714 * appeared on the screen.
1715 */
1716static int
1717tty3270_chars_in_buffer(struct tty_struct *tty)
1718{
1719	return 0;
1720}
1721
1722static void
1723tty3270_flush_buffer(struct tty_struct *tty)
1724{
1725}
1726
1727/*
1728 * Check for visible/invisible input switches
1729 */
1730static void
1731tty3270_set_termios(struct tty_struct *tty, struct ktermios *old)
1732{
1733	struct tty3270 *tp;
1734	int new;
1735
1736	tp = tty->driver_data;
1737	if (!tp)
1738		return;
1739	spin_lock_bh(&tp->view.lock);
1740	if (L_ICANON(tty)) {
1741		new = L_ECHO(tty) ? TF_INPUT: TF_INPUTN;
1742		if (new != tp->inattr) {
1743			tp->inattr = new;
1744			tty3270_update_prompt(tp, NULL, 0);
1745			tty3270_set_timer(tp, 1);
1746		}
1747	}
1748	spin_unlock_bh(&tp->view.lock);
1749}
1750
1751/*
1752 * Disable reading from a 3270 tty
1753 */
1754static void
1755tty3270_throttle(struct tty_struct * tty)
1756{
1757	struct tty3270 *tp;
1758
1759	tp = tty->driver_data;
1760	if (!tp)
1761		return;
1762	tp->throttle = 1;
1763}
1764
1765/*
1766 * Enable reading from a 3270 tty
1767 */
1768static void
1769tty3270_unthrottle(struct tty_struct * tty)
1770{
1771	struct tty3270 *tp;
1772
1773	tp = tty->driver_data;
1774	if (!tp)
1775		return;
1776	tp->throttle = 0;
1777	if (tp->attn)
1778		tty3270_issue_read(tp, 1);
1779}
1780
1781/*
1782 * Hang up the tty device.
1783 */
1784static void
1785tty3270_hangup(struct tty_struct *tty)
1786{
1787	// FIXME: implement
1788}
1789
1790static void
1791tty3270_wait_until_sent(struct tty_struct *tty, int timeout)
1792{
1793}
1794
1795static int tty3270_ioctl(struct tty_struct *tty, unsigned int cmd,
1796			 unsigned long arg)
1797{
1798	struct tty3270 *tp;
1799
1800	tp = tty->driver_data;
1801	if (!tp)
1802		return -ENODEV;
1803	if (tty->flags & (1 << TTY_IO_ERROR))
1804		return -EIO;
1805	return kbd_ioctl(tp->kbd, cmd, arg);
1806}
1807
1808#ifdef CONFIG_COMPAT
1809static long tty3270_compat_ioctl(struct tty_struct *tty,
1810				 unsigned int cmd, unsigned long arg)
1811{
1812	struct tty3270 *tp;
1813
1814	tp = tty->driver_data;
1815	if (!tp)
1816		return -ENODEV;
1817	if (tty->flags & (1 << TTY_IO_ERROR))
1818		return -EIO;
1819	return kbd_ioctl(tp->kbd, cmd, (unsigned long)compat_ptr(arg));
1820}
1821#endif
1822
1823static const struct tty_operations tty3270_ops = {
1824	.install = tty3270_install,
1825	.cleanup = tty3270_cleanup,
1826	.open = tty3270_open,
1827	.close = tty3270_close,
1828	.write = tty3270_write,
1829	.put_char = tty3270_put_char,
1830	.flush_chars = tty3270_flush_chars,
1831	.write_room = tty3270_write_room,
1832	.chars_in_buffer = tty3270_chars_in_buffer,
1833	.flush_buffer = tty3270_flush_buffer,
1834	.throttle = tty3270_throttle,
1835	.unthrottle = tty3270_unthrottle,
1836	.hangup = tty3270_hangup,
1837	.wait_until_sent = tty3270_wait_until_sent,
1838	.ioctl = tty3270_ioctl,
1839#ifdef CONFIG_COMPAT
1840	.compat_ioctl = tty3270_compat_ioctl,
1841#endif
1842	.set_termios = tty3270_set_termios
1843};
1844
1845static void tty3270_create_cb(int minor)
1846{
1847	tty_register_device(tty3270_driver, minor - RAW3270_FIRSTMINOR, NULL);
1848}
1849
1850static void tty3270_destroy_cb(int minor)
1851{
1852	tty_unregister_device(tty3270_driver, minor - RAW3270_FIRSTMINOR);
1853}
1854
1855static struct raw3270_notifier tty3270_notifier =
1856{
1857	.create = tty3270_create_cb,
1858	.destroy = tty3270_destroy_cb,
1859};
1860
1861/*
1862 * 3270 tty registration code called from tty_init().
1863 * Most kernel services (incl. kmalloc) are available at this poimt.
1864 */
1865static int __init tty3270_init(void)
1866{
1867	struct tty_driver *driver;
1868	int ret;
1869
1870	driver = tty_alloc_driver(RAW3270_MAXDEVS,
1871				  TTY_DRIVER_REAL_RAW |
1872				  TTY_DRIVER_DYNAMIC_DEV |
1873				  TTY_DRIVER_RESET_TERMIOS);
1874	if (IS_ERR(driver))
1875		return PTR_ERR(driver);
1876
1877	/*
1878	 * Initialize the tty_driver structure
1879	 * Entries in tty3270_driver that are NOT initialized:
1880	 * proc_entry, set_termios, flush_buffer, set_ldisc, write_proc
1881	 */
1882	driver->driver_name = "tty3270";
1883	driver->name = "3270/tty";
1884	driver->major = IBM_TTY3270_MAJOR;
1885	driver->minor_start = RAW3270_FIRSTMINOR;
1886	driver->name_base = RAW3270_FIRSTMINOR;
1887	driver->type = TTY_DRIVER_TYPE_SYSTEM;
1888	driver->subtype = SYSTEM_TYPE_TTY;
1889	driver->init_termios = tty_std_termios;
1890	tty_set_operations(driver, &tty3270_ops);
1891	ret = tty_register_driver(driver);
1892	if (ret) {
1893		put_tty_driver(driver);
1894		return ret;
1895	}
1896	tty3270_driver = driver;
1897	raw3270_register_notifier(&tty3270_notifier);
1898	return 0;
1899}
1900
1901static void __exit
1902tty3270_exit(void)
1903{
1904	struct tty_driver *driver;
1905
1906	raw3270_unregister_notifier(&tty3270_notifier);
1907	driver = tty3270_driver;
1908	tty3270_driver = NULL;
1909	tty_unregister_driver(driver);
1910	put_tty_driver(driver);
1911	tty3270_del_views();
1912}
1913
1914MODULE_LICENSE("GPL");
1915MODULE_ALIAS_CHARDEV_MAJOR(IBM_TTY3270_MAJOR);
1916
1917module_init(tty3270_init);
1918module_exit(tty3270_exit);
1919