drivers/s390/char/tty3270.c

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