drivers/s390/char/con3215.c

   1 /*
   2  *  drivers/s390/char/con3215.c
   3  *    3215 line mode terminal driver.
   4  *
   5  *  S390 version
   6  *    Copyright (C) 1999,2000 IBM Deutschland Entwicklung GmbH, IBM Corporation
   7  *    Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
   8  *
   9  *  Updated:
  10  *   Aug-2000: Added tab support
  11  *             Dan Morrison, IBM Corporation (dmorriso@cse.buffalo.edu)
  12  */
  13
  14 #include <linux/config.h>
  15 #include <linux/module.h>
  16 #include <linux/types.h>
  17 #include <linux/kdev_t.h>
  18 #include <linux/tty.h>
  19 #include <linux/vt_kern.h>
  20 #include <linux/init.h>
  21 #include <linux/console.h>
  22 #include <linux/interrupt.h>
  23
  24 #include <linux/slab.h>
  25 #include <linux/bootmem.h>
  26
  27 #include <asm/ccwdev.h>
  28 #include <asm/cio.h>
  29 #include <asm/io.h>
  30 #include <asm/ebcdic.h>
  31 #include <asm/uaccess.h>
  32 #include <asm/delay.h>
  33 #include <asm/cpcmd.h>
  34 #include <asm/setup.h>
  35
  36 #include "ctrlchar.h"
  37
  38 #define NR_3215             1
  39 #define NR_3215_REQ         (4*NR_3215)
  40 #define RAW3215_BUFFER_SIZE 65536     /* output buffer size */
  41 #define RAW3215_INBUF_SIZE  256       /* input buffer size */
  42 #define RAW3215_MIN_SPACE   128       /* minimum free space for wakeup */
  43 #define RAW3215_MIN_WRITE   1024      /* min. length for immediate output */
  44 #define RAW3215_MAX_BYTES   3968      /* max. bytes to write with one ssch */
  45 #define RAW3215_MAX_NEWLINE 50        /* max. lines to write with one ssch */
  46 #define RAW3215_NR_CCWS     3
  47 #define RAW3215_TIMEOUT     HZ/10     /* time for delayed output */
  48
  49 #define RAW3215_FIXED       1         /* 3215 console device is not be freed */
  50 #define RAW3215_ACTIVE      2         /* set if the device is in use */
  51 #define RAW3215_WORKING     4         /* set if a request is being worked on */
  52 #define RAW3215_THROTTLED   8         /* set if reading is disabled */
  53 #define RAW3215_STOPPED     16        /* set if writing is disabled */
  54 #define RAW3215_CLOSING     32        /* set while in close process */
  55 #define RAW3215_TIMER_RUNS  64        /* set if the output delay timer is on */
  56 #define RAW3215_FLUSHING    128       /* set to flush buffer (no delay) */
  57
  58 #define TAB_STOP_SIZE       8         /* tab stop size */
  59
  60 /*
  61  * Request types for a 3215 device
  62  */
  63 enum raw3215_type {
  64         RAW3215_FREE, RAW3215_READ, RAW3215_WRITE
  65 };
  66
  67 /*
  68  * Request structure for a 3215 device
  69  */
  70 struct raw3215_req {
  71         enum raw3215_type type;       /* type of the request */
  72         int start, len;               /* start index & len in output buffer */
  73         int delayable;                /* indication to wait for more data */
  74         int residual;                 /* residual count for read request */
  75         struct ccw1 ccws[RAW3215_NR_CCWS]; /* space for the channel program */
  76         struct raw3215_info *info;    /* pointer to main structure */
  77         struct raw3215_req *next;     /* pointer to next request */
  78 } __attribute__ ((aligned(8)));
  79
  80 struct raw3215_info {
  81         struct ccw_device *cdev;      /* device for tty driver */
  82         spinlock_t *lock;             /* pointer to irq lock */
  83         int flags;                    /* state flags */
  84         char *buffer;                 /* pointer to output buffer */
  85         char *inbuf;                  /* pointer to input buffer */
  86         int head;                     /* first free byte in output buffer */
  87         int count;                    /* number of bytes in output buffer */
  88         int written;                  /* number of bytes in write requests */
  89         struct tty_struct *tty;       /* pointer to tty structure if present */
  90         struct tasklet_struct tasklet;
  91         struct raw3215_req *queued_read; /* pointer to queued read requests */
  92         struct raw3215_req *queued_write;/* pointer to queued write requests */
  93         wait_queue_head_t empty_wait; /* wait queue for flushing */
  94         struct timer_list timer;      /* timer for delayed output */
  95         char *message;                /* pending message from raw3215_irq */
  96         int msg_dstat;                /* dstat for pending message */
  97         int msg_cstat;                /* cstat for pending message */
  98         int line_pos;                 /* position on the line (for tabs) */
  99         char ubuffer[80];             /* copy_from_user buffer */
 100 };
 101
 102 /* array of 3215 devices structures */
 103 static struct raw3215_info *raw3215[NR_3215];
 104 /* spinlock to protect the raw3215 array */
 105 static spinlock_t raw3215_device_lock = SPIN_LOCK_UNLOCKED;
 106 /* list of free request structures */
 107 static struct raw3215_req *raw3215_freelist;
 108 /* spinlock to protect free list */
 109 static spinlock_t raw3215_freelist_lock;
 110
 111 static struct tty_driver *tty3215_driver;
 112
 113 /*
 114  * Get a request structure from the free list
 115  */
 116 static inline struct raw3215_req *
 117 raw3215_alloc_req(void) {
 118         struct raw3215_req *req;
 119         unsigned long flags;
 120
 121         spin_lock_irqsave(&raw3215_freelist_lock, flags);
 122         req = raw3215_freelist;
 123         raw3215_freelist = req->next;
 124         spin_unlock_irqrestore(&raw3215_freelist_lock, flags);
 125         return req;
 126 }
 127
 128 /*
 129  * Put a request structure back to the free list
 130  */
 131 static inline void
 132 raw3215_free_req(struct raw3215_req *req) {
 133         unsigned long flags;
 134
 135         if (req->type == RAW3215_FREE)
 136                 return;         /* don't free a free request */
 137         req->type = RAW3215_FREE;
 138         spin_lock_irqsave(&raw3215_freelist_lock, flags);
 139         req->next = raw3215_freelist;
 140         raw3215_freelist = req;
 141         spin_unlock_irqrestore(&raw3215_freelist_lock, flags);
 142 }
 143
 144 /*
 145  * Set up a read request that reads up to 160 byte from the 3215 device.
 146  * If there is a queued read request it is used, but that shouldn't happen
 147  * because a 3215 terminal won't accept a new read before the old one is
 148  * completed.
 149  */
 150 static void
 151 raw3215_mk_read_req(struct raw3215_info *raw)
 152 {
 153         struct raw3215_req *req;
 154         struct ccw1 *ccw;
 155
 156         /* there can only be ONE read request at a time */
 157         req = raw->queued_read;
 158         if (req == NULL) {
 159                 /* no queued read request, use new req structure */
 160                 req = raw3215_alloc_req();
 161                 req->type = RAW3215_READ;
 162                 req->info = raw;
 163                 raw->queued_read = req;
 164         }
 165
 166         ccw = req->ccws;
 167         ccw->cmd_code = 0x0A; /* read inquiry */
 168         ccw->flags = 0x20;    /* ignore incorrect length */
 169         ccw->count = 160;
 170         ccw->cda = (__u32) __pa(raw->inbuf);
 171 }
 172
 173 /*
 174  * Set up a write request with the information from the main structure.
 175  * A ccw chain is created that writes as much as possible from the output
 176  * buffer to the 3215 device. If a queued write exists it is replaced by
 177  * the new, probably lengthened request.
 178  */
 179 static void
 180 raw3215_mk_write_req(struct raw3215_info *raw)
 181 {
 182         struct raw3215_req *req;
 183         struct ccw1 *ccw;
 184         int len, count, ix, lines;
 185
 186         if (raw->count <= raw->written)
 187                 return;
 188         /* check if there is a queued write request */
 189         req = raw->queued_write;
 190         if (req == NULL) {
 191                 /* no queued write request, use new req structure */
 192                 req = raw3215_alloc_req();
 193                 req->type = RAW3215_WRITE;
 194                 req->info = raw;
 195                 raw->queued_write = req;
 196         } else {
 197                 raw->written -= req->len;
 198         }
 199
 200         ccw = req->ccws;
 201         req->start = (raw->head - raw->count + raw->written) &
 202                      (RAW3215_BUFFER_SIZE - 1);
 203         /*
 204          * now we have to count newlines. We can at max accept
 205          * RAW3215_MAX_NEWLINE newlines in a single ssch due to
 206          * a restriction in VM
 207          */
 208         lines = 0;
 209         ix = req->start;
 210         while (lines < RAW3215_MAX_NEWLINE && ix != raw->head) {
 211                 if (raw->buffer[ix] == 0x15)
 212                         lines++;
 213                 ix = (ix + 1) & (RAW3215_BUFFER_SIZE - 1);
 214         }
 215         len = ((ix - 1 - req->start) & (RAW3215_BUFFER_SIZE - 1)) + 1;
 216         if (len > RAW3215_MAX_BYTES)
 217                 len = RAW3215_MAX_BYTES;
 218         req->len = len;
 219         raw->written += len;
 220
 221         /* set the indication if we should try to enlarge this request */
 222         req->delayable = (ix == raw->head) && (len < RAW3215_MIN_WRITE);
 223
 224         ix = req->start;
 225         while (len > 0) {
 226                 if (ccw > req->ccws)
 227                         ccw[-1].flags |= 0x40; /* use command chaining */
 228                 ccw->cmd_code = 0x01; /* write, auto carrier return */
 229                 ccw->flags = 0x20;    /* ignore incorrect length ind.  */
 230                 ccw->cda =
 231                         (__u32) __pa(raw->buffer + ix);
 232                 count = len;
 233                 if (ix + count > RAW3215_BUFFER_SIZE)
 234                         count = RAW3215_BUFFER_SIZE - ix;
 235                 ccw->count = count;
 236                 len -= count;
 237                 ix = (ix + count) & (RAW3215_BUFFER_SIZE - 1);
 238                 ccw++;
 239         }
 240         /*
 241          * Add a NOP to the channel program. 3215 devices are purely
 242          * emulated and its much better to avoid the channel end
 243          * interrupt in this case.
 244          */
 245         if (ccw > req->ccws)
 246                 ccw[-1].flags |= 0x40; /* use command chaining */
 247         ccw->cmd_code = 0x03; /* NOP */
 248         ccw->flags = 0;
 249         ccw->cda = 0;
 250         ccw->count = 1;
 251 }
 252
 253 /*
 254  * Start a read or a write request
 255  */
 256 static void
 257 raw3215_start_io(struct raw3215_info *raw)
 258 {
 259         struct raw3215_req *req;
 260         int res;
 261
 262         req = raw->queued_read;
 263         if (req != NULL &&
 264             !(raw->flags & (RAW3215_WORKING | RAW3215_THROTTLED))) {
 265                 /* dequeue request */
 266                 raw->queued_read = NULL;
 267                 res = ccw_device_start(raw->cdev, req->ccws,
 268                                        (unsigned long) req, 0, 0);
 269                 if (res != 0) {
 270                         /* do_IO failed, put request back to queue */
 271                         raw->queued_read = req;
 272                 } else {
 273                         raw->flags |= RAW3215_WORKING;
 274                 }
 275         }
 276         req = raw->queued_write;
 277         if (req != NULL &&
 278             !(raw->flags & (RAW3215_WORKING | RAW3215_STOPPED))) {
 279                 /* dequeue request */
 280                 raw->queued_write = NULL;
 281                 res = ccw_device_start(raw->cdev, req->ccws,
 282                                        (unsigned long) req, 0, 0);
 283                 if (res != 0) {
 284                         /* do_IO failed, put request back to queue */
 285                         raw->queued_write = req;
 286                 } else {
 287                         raw->flags |= RAW3215_WORKING;
 288                 }
 289         }
 290 }
 291
 292 /*
 293  * Function to start a delayed output after RAW3215_TIMEOUT seconds
 294  */
 295 static void
 296 raw3215_timeout(unsigned long __data)
 297 {
 298         struct raw3215_info *raw = (struct raw3215_info *) __data;
 299         unsigned long flags;
 300
 301         spin_lock_irqsave(raw->lock, flags);
 302         if (raw->flags & RAW3215_TIMER_RUNS) {
 303                 del_timer(&raw->timer);
 304                 raw->flags &= ~RAW3215_TIMER_RUNS;
 305                 raw3215_mk_write_req(raw);
 306                 raw3215_start_io(raw);
 307         }
 308         spin_unlock_irqrestore(raw->lock, flags);
 309 }
 310
 311 /*
 312  * Function to conditionally start an IO. A read is started immediately,
 313  * a write is only started immediately if the flush flag is on or the
 314  * amount of data is bigger than RAW3215_MIN_WRITE. If a write is not
 315  * done immediately a timer is started with a delay of RAW3215_TIMEOUT.
 316  */
 317 static inline void
 318 raw3215_try_io(struct raw3215_info *raw)
 319 {
 320         if (!(raw->flags & RAW3215_ACTIVE))
 321                 return;
 322         if (raw->queued_read != NULL)
 323                 raw3215_start_io(raw);
 324         else if (raw->queued_write != NULL) {
 325                 if ((raw->queued_write->delayable == 0) ||
 326                     (raw->flags & RAW3215_FLUSHING)) {
 327                         /* execute write requests bigger than minimum size */
 328                         raw3215_start_io(raw);
 329                         if (raw->flags & RAW3215_TIMER_RUNS) {
 330                                 del_timer(&raw->timer);
 331                                 raw->flags &= ~RAW3215_TIMER_RUNS;
 332                         }
 333                 } else if (!(raw->flags & RAW3215_TIMER_RUNS)) {
 334                         /* delay small writes */
 335                         init_timer(&raw->timer);
 336                         raw->timer.expires = RAW3215_TIMEOUT + jiffies;
 337                         raw->timer.data = (unsigned long) raw;
 338                         raw->timer.function = raw3215_timeout;
 339                         add_timer(&raw->timer);
 340                         raw->flags |= RAW3215_TIMER_RUNS;
 341                 }
 342         }
 343 }
 344
 345 /*
 346  * The bottom half handler routine for 3215 devices. It tries to start
 347  * the next IO and wakes up processes waiting on the tty.
 348  */
 349 static void
 350 raw3215_tasklet(void *data)
 351 {
 352         struct raw3215_info *raw;
 353         struct tty_struct *tty;
 354         unsigned long flags;
 355
 356         raw = (struct raw3215_info *) data;
 357         spin_lock_irqsave(raw->lock, flags);
 358         raw3215_mk_write_req(raw);
 359         raw3215_try_io(raw);
 360         spin_unlock_irqrestore(raw->lock, flags);
 361         /* Check for pending message from raw3215_irq */
 362         if (raw->message != NULL) {
 363                 printk(raw->message, raw->msg_dstat, raw->msg_cstat);
 364                 raw->message = NULL;
 365         }
 366         tty = raw->tty;
 367         if (tty != NULL &&
 368             RAW3215_BUFFER_SIZE - raw->count >= RAW3215_MIN_SPACE) {
 369                 tty_wakeup(tty);
 370         }
 371 }
 372
 373 /*
 374  * Interrupt routine, called from common io layer
 375  */
 376 static void
 377 raw3215_irq(struct ccw_device *cdev, unsigned long intparm, struct irb *irb)
 378 {
 379         struct raw3215_info *raw;
 380         struct raw3215_req *req;
 381         struct tty_struct *tty;
 382         int cstat, dstat;
 383         int count, slen;
 384
 385         raw = cdev->dev.driver_data;
 386         req = (struct raw3215_req *) intparm;
 387         cstat = irb->scsw.cstat;
 388         dstat = irb->scsw.dstat;
 389         if (cstat != 0) {
 390                 raw->message = KERN_WARNING
 391                         "Got nonzero channel status in raw3215_irq "
 392                         "(dev sts 0x%2x, sch sts 0x%2x)";
 393                 raw->msg_dstat = dstat;
 394                 raw->msg_cstat = cstat;
 395                 tasklet_schedule(&raw->tasklet);
 396         }
 397         if (dstat & 0x01) { /* we got a unit exception */
 398                 dstat &= ~0x01;  /* we can ignore it */
 399         }
 400         switch (dstat) {
 401         case 0x80:
 402                 if (cstat != 0)
 403                         break;
 404                 /* Attention interrupt, someone hit the enter key */
 405                 raw3215_mk_read_req(raw);
 406                 if (MACHINE_IS_P390)
 407                         memset(raw->inbuf, 0, RAW3215_INBUF_SIZE);
 408                 tasklet_schedule(&raw->tasklet);
 409                 break;
 410         case 0x08:
 411         case 0x0C:
 412                 /* Channel end interrupt. */
 413                 if ((raw = req->info) == NULL)
 414                         return;              /* That shouldn't happen ... */
 415                 if (req->type == RAW3215_READ) {
 416                         /* store residual count, then wait for device end */
 417                         req->residual = irb->scsw.count;
 418                 }
 419                 if (dstat == 0x08)
 420                         break;
 421         case 0x04:
 422                 /* Device end interrupt. */
 423                 if ((raw = req->info) == NULL)
 424                         return;              /* That shouldn't happen ... */
 425                 if (req->type == RAW3215_READ && raw->tty != NULL) {
 426                         unsigned int cchar;
 427
 428                         tty = raw->tty;
 429                         count = 160 - req->residual;
 430                         if (MACHINE_IS_P390) {
 431                                 slen = strnlen(raw->inbuf, RAW3215_INBUF_SIZE);
 432                                 if (count > slen)
 433                                         count = slen;
 434                         } else
 435                         if (count >= TTY_FLIPBUF_SIZE - tty->flip.count)
 436                                 count = TTY_FLIPBUF_SIZE - tty->flip.count - 1;
 437                         EBCASC(raw->inbuf, count);
 438                         cchar = ctrlchar_handle(raw->inbuf, count, tty);
 439                         switch (cchar & CTRLCHAR_MASK) {
 440                         case CTRLCHAR_SYSRQ:
 441                                 break;
 442
 443                         case CTRLCHAR_CTRL:
 444                                 tty->flip.count++;
 445                                 *tty->flip.flag_buf_ptr++ = TTY_NORMAL;
 446                                 *tty->flip.char_buf_ptr++ = cchar;
 447                                 tty_flip_buffer_push(raw->tty);
 448                                 break;
 449
 450                         case CTRLCHAR_NONE:
 451                                 memcpy(tty->flip.char_buf_ptr,
 452                                        raw->inbuf, count);
 453                                 if (count < 2 ||
 454                                     (strncmp(raw->inbuf+count-2, "^n", 2) &&
 455                                     strncmp(raw->inbuf+count-2, "\252n", 2)) ) {
 456                                         /* don't add the auto \n */
 457                                         tty->flip.char_buf_ptr[count] = '\n';
 458                                         memset(tty->flip.flag_buf_ptr,
 459                                                TTY_NORMAL, count + 1);
 460                                         count++;
 461                                 } else
 462                                         count-=2;
 463                                 tty->flip.char_buf_ptr += count;
 464                                 tty->flip.flag_buf_ptr += count;
 465                                 tty->flip.count += count;
 466                                 tty_flip_buffer_push(raw->tty);
 467                                 break;
 468                         }
 469                 } else if (req->type == RAW3215_WRITE) {
 470                         raw->count -= req->len;
 471                         raw->written -= req->len;
 472                 }
 473                 raw->flags &= ~RAW3215_WORKING;
 474                 raw3215_free_req(req);
 475                 /* check for empty wait */
 476                 if (waitqueue_active(&raw->empty_wait) &&
 477                     raw->queued_write == NULL &&
 478                     raw->queued_read == NULL) {
 479                         wake_up_interruptible(&raw->empty_wait);
 480                 }
 481                 tasklet_schedule(&raw->tasklet);
 482                 break;
 483         default:
 484                 /* Strange interrupt, I'll do my best to clean up */
 485                 if (req != NULL && req->type != RAW3215_FREE) {
 486                         if (req->type == RAW3215_WRITE) {
 487                                 raw->count -= req->len;
 488                                 raw->written -= req->len;
 489                         }
 490                         raw->flags &= ~RAW3215_WORKING;
 491                         raw3215_free_req(req);
 492                 }
 493                 raw->message = KERN_WARNING
 494                         "Spurious interrupt in in raw3215_irq "
 495                         "(dev sts 0x%2x, sch sts 0x%2x)";
 496                 raw->msg_dstat = dstat;
 497                 raw->msg_cstat = cstat;
 498                 tasklet_schedule(&raw->tasklet);
 499         }
 500         return;
 501 }
 502
 503 /*
 504  * Wait until length bytes are available int the output buffer.
 505  * Has to be called with the s390irq lock held. Can be called
 506  * disabled.
 507  */
 508 static void
 509 raw3215_make_room(struct raw3215_info *raw, unsigned int length)
 510 {
 511         while (RAW3215_BUFFER_SIZE - raw->count < length) {
 512                 /* there might be a request pending */
 513                 raw->flags |= RAW3215_FLUSHING;
 514                 raw3215_mk_write_req(raw);
 515                 raw3215_try_io(raw);
 516                 raw->flags &= ~RAW3215_FLUSHING;
 517 #ifdef CONFIG_TN3215_CONSOLE
 518                 wait_cons_dev();
 519 #endif
 520                 /* Enough room freed up ? */
 521                 if (RAW3215_BUFFER_SIZE - raw->count >= length)
 522                         break;
 523                 /* there might be another cpu waiting for the lock */
 524                 spin_unlock(raw->lock);
 525                 udelay(100);
 526                 spin_lock(raw->lock);
 527         }
 528 }
 529
 530 /*
 531  * String write routine for 3215 devices
 532  */
 533 static void
 534 raw3215_write(struct raw3215_info *raw, const char *str, unsigned int length)
 535 {
 536         unsigned long flags;
 537         int c, count;
 538
 539         while (length > 0) {
 540                 spin_lock_irqsave(raw->lock, flags);
 541                 count = (length > RAW3215_BUFFER_SIZE) ?
 542                                              RAW3215_BUFFER_SIZE : length;
 543                 length -= count;
 544
 545                 raw3215_make_room(raw, count);
 546
 547                 /* copy string to output buffer and convert it to EBCDIC */
 548                 while (1) {
 549                         c = min_t(int, count,
 550                                   min(RAW3215_BUFFER_SIZE - raw->count,
 551                                       RAW3215_BUFFER_SIZE - raw->head));
 552                         if (c <= 0)
 553                                 break;
 554                         memcpy(raw->buffer + raw->head, str, c);
 555                         ASCEBC(raw->buffer + raw->head, c);
 556                         raw->head = (raw->head + c) & (RAW3215_BUFFER_SIZE - 1);
 557                         raw->count += c;
 558                         raw->line_pos += c;
 559                         str += c;
 560                         count -= c;
 561                 }
 562                 if (!(raw->flags & RAW3215_WORKING)) {
 563                         raw3215_mk_write_req(raw);
 564                         /* start or queue request */
 565                         raw3215_try_io(raw);
 566                 }
 567                 spin_unlock_irqrestore(raw->lock, flags);
 568         }
 569 }
 570
 571 /*
 572  * Put character routine for 3215 devices
 573  */
 574 static void
 575 raw3215_putchar(struct raw3215_info *raw, unsigned char ch)
 576 {
 577         unsigned long flags;
 578         unsigned int length, i;
 579
 580         spin_lock_irqsave(raw->lock, flags);
 581         if (ch == '\t') {
 582                 length = TAB_STOP_SIZE - (raw->line_pos%TAB_STOP_SIZE);
 583                 raw->line_pos += length;
 584                 ch = ' ';
 585         } else if (ch == '\n') {
 586                 length = 1;
 587                 raw->line_pos = 0;
 588         } else {
 589                 length = 1;
 590                 raw->line_pos++;
 591         }
 592         raw3215_make_room(raw, length);
 593
 594         for (i = 0; i < length; i++) {
 595                 raw->buffer[raw->head] = (char) _ascebc[(int) ch];
 596                 raw->head = (raw->head + 1) & (RAW3215_BUFFER_SIZE - 1);
 597                 raw->count++;
 598         }
 599         if (!(raw->flags & RAW3215_WORKING)) {
 600                 raw3215_mk_write_req(raw);
 601                 /* start or queue request */
 602                 raw3215_try_io(raw);
 603         }
 604         spin_unlock_irqrestore(raw->lock, flags);
 605 }
 606
 607 /*
 608  * Flush routine, it simply sets the flush flag and tries to start
 609  * pending IO.
 610  */
 611 static void
 612 raw3215_flush_buffer(struct raw3215_info *raw)
 613 {
 614         unsigned long flags;
 615
 616         spin_lock_irqsave(raw->lock, flags);
 617         if (raw->count > 0) {
 618                 raw->flags |= RAW3215_FLUSHING;
 619                 raw3215_try_io(raw);
 620                 raw->flags &= ~RAW3215_FLUSHING;
 621         }
 622         spin_unlock_irqrestore(raw->lock, flags);
 623 }
 624
 625 /*
 626  * Fire up a 3215 device.
 627  */
 628 static int
 629 raw3215_startup(struct raw3215_info *raw)
 630 {
 631         unsigned long flags;
 632
 633         if (raw->flags & RAW3215_ACTIVE)
 634                 return 0;
 635         raw->line_pos = 0;
 636         raw->flags |= RAW3215_ACTIVE;
 637         spin_lock_irqsave(raw->lock, flags);
 638         raw3215_try_io(raw);
 639         spin_unlock_irqrestore(raw->lock, flags);
 640
 641         return 0;
 642 }
 643
 644 /*
 645  * Shutdown a 3215 device.
 646  */
 647 static void
 648 raw3215_shutdown(struct raw3215_info *raw)
 649 {
 650         DECLARE_WAITQUEUE(wait, current);
 651         unsigned long flags;
 652
 653         if (!(raw->flags & RAW3215_ACTIVE) || (raw->flags & RAW3215_FIXED))
 654                 return;
 655         /* Wait for outstanding requests, then free irq */
 656         spin_lock_irqsave(raw->lock, flags);
 657         if ((raw->flags & RAW3215_WORKING) ||
 658             raw->queued_write != NULL ||
 659             raw->queued_read != NULL) {
 660                 raw->flags |= RAW3215_CLOSING;
 661                 add_wait_queue(&raw->empty_wait, &wait);
 662                 set_current_state(TASK_INTERRUPTIBLE);
 663                 spin_unlock_irqrestore(raw->lock, flags);
 664                 schedule();
 665                 spin_lock_irqsave(raw->lock, flags);
 666                 remove_wait_queue(&raw->empty_wait, &wait);
 667                 set_current_state(TASK_RUNNING);
 668                 raw->flags &= ~(RAW3215_ACTIVE | RAW3215_CLOSING);
 669         }
 670         spin_unlock_irqrestore(raw->lock, flags);
 671 }
 672
 673 static int
 674 raw3215_probe (struct ccw_device *cdev)
 675 {
 676         struct raw3215_info *raw;
 677         int line;
 678
 679         raw = kmalloc(sizeof(struct raw3215_info) +
 680                       RAW3215_INBUF_SIZE, GFP_KERNEL|GFP_DMA);
 681         if (raw == NULL)
 682                 return -ENOMEM;
 683
 684         spin_lock(&raw3215_device_lock);
 685         for (line = 0; line < NR_3215; line++) {
 686                 if (!raw3215[line]) {
 687                         raw3215[line] = raw;
 688                         break;
 689                 }
 690         }
 691         spin_unlock(&raw3215_device_lock);
 692         if (line == NR_3215) {
 693                 kfree(raw);
 694                 return -ENODEV;
 695         }
 696
 697         raw->cdev = cdev;
 698         raw->lock = get_ccwdev_lock(cdev);
 699         raw->inbuf = (char *) raw + sizeof(struct raw3215_info);
 700         memset(raw, 0, sizeof(struct raw3215_info));
 701         raw->buffer = (char *) kmalloc(RAW3215_BUFFER_SIZE,
 702                                        GFP_KERNEL|GFP_DMA);
 703         if (raw->buffer == NULL) {
 704                 spin_lock(&raw3215_device_lock);
 705                 raw3215[line] = 0;
 706                 spin_unlock(&raw3215_device_lock);
 707                 kfree(raw);
 708                 return -ENOMEM;
 709         }
 710         tasklet_init(&raw->tasklet,
 711                      (void (*)(unsigned long)) raw3215_tasklet,
 712                      (unsigned long) raw);
 713         init_waitqueue_head(&raw->empty_wait);
 714
 715         cdev->dev.driver_data = raw;
 716         cdev->handler = raw3215_irq;
 717
 718         return 0;
 719 }
 720
 721 static void
 722 raw3215_remove (struct ccw_device *cdev)
 723 {
 724         struct raw3215_info *raw;
 725
 726         ccw_device_set_offline(cdev);
 727         raw = cdev->dev.driver_data;
 728         if (raw) {
 729                 cdev->dev.driver_data = NULL;
 730                 if (raw->buffer)
 731                         kfree(raw->buffer);
 732                 kfree(raw);
 733         }
 734 }
 735
 736 static int
 737 raw3215_set_online (struct ccw_device *cdev)
 738 {
 739         struct raw3215_info *raw;
 740
 741         raw = cdev->dev.driver_data;
 742         if (!raw)
 743                 return -ENODEV;
 744
 745         return raw3215_startup(raw);
 746 }
 747
 748 static int
 749 raw3215_set_offline (struct ccw_device *cdev)
 750 {
 751         struct raw3215_info *raw;
 752
 753         raw = cdev->dev.driver_data;
 754         if (!raw)
 755                 return -ENODEV;
 756
 757         raw3215_shutdown(raw);
 758
 759         return 0;
 760 }
 761
 762 static struct ccw_device_id raw3215_id[] = {
 763         { CCW_DEVICE(0x3215, 0) },
 764         { /* end of list */ },
 765 };
 766
 767 static struct ccw_driver raw3215_ccw_driver = {
 768         .name           = "3215",
 769         .owner          = THIS_MODULE,
 770         .ids            = raw3215_id,
 771         .probe          = &raw3215_probe,
 772         .remove         = &raw3215_remove,
 773         .set_online     = &raw3215_set_online,
 774         .set_offline    = &raw3215_set_offline,
 775 };
 776
 777 #ifdef CONFIG_TN3215_CONSOLE
 778 /*
 779  * Write a string to the 3215 console
 780  */
 781 static void
 782 con3215_write(struct console *co, const char *str, unsigned int count)
 783 {
 784         struct raw3215_info *raw;
 785         int i;
 786
 787         if (count <= 0)
 788                 return;
 789         raw = raw3215[0];       /* console 3215 is the first one */
 790         while (count > 0) {
 791                 for (i = 0; i < count; i++)
 792                         if (str[i] == '\t' || str[i] == '\n')
 793                                 break;
 794                 raw3215_write(raw, str, i);
 795                 count -= i;
 796                 str += i;
 797                 if (count > 0) {
 798                         raw3215_putchar(raw, *str);
 799                         count--;
 800                         str++;
 801                 }
 802         }
 803 }
 804
 805 static struct tty_driver *con3215_device(struct console *c, int *index)
 806 {
 807         *index = c->index;
 808         return tty3215_driver;
 809 }
 810
 811 /*
 812  * panic() calls console_unblank before the system enters a
 813  * disabled, endless loop.
 814  */
 815 static void
 816 con3215_unblank(void)
 817 {
 818         struct raw3215_info *raw;
 819         unsigned long flags;
 820
 821         raw = raw3215[0];  /* console 3215 is the first one */
 822         spin_lock_irqsave(raw->lock, flags);
 823         raw3215_make_room(raw, RAW3215_BUFFER_SIZE);
 824         spin_unlock_irqrestore(raw->lock, flags);
 825 }
 826
 827 static int __init
 828 con3215_consetup(struct console *co, char *options)
 829 {
 830         return 0;
 831 }
 832
 833 /*
 834  *  The console structure for the 3215 console
 835  */
 836 static struct console con3215 = {
 837         .name    = "ttyS",
 838         .write   = con3215_write,
 839         .device  = con3215_device,
 840         .unblank = con3215_unblank,
 841         .setup   = con3215_consetup,
 842         .flags   = CON_PRINTBUFFER,
 843 };
 844
 845 /*
 846  * 3215 console initialization code called from console_init().
 847  * NOTE: This is called before kmalloc is available.
 848  */
 849 static int __init
 850 con3215_init(void)
 851 {
 852         struct ccw_device *cdev;
 853         struct raw3215_info *raw;
 854         struct raw3215_req *req;
 855         int i;
 856
 857         /* Check if 3215 is to be the console */
 858         if (!CONSOLE_IS_3215)
 859                 return -ENODEV;
 860
 861         /* Set the console mode for VM */
 862         if (MACHINE_IS_VM) {
 863                 cpcmd("TERM CONMODE 3215", NULL, 0);
 864                 cpcmd("TERM AUTOCR OFF", NULL, 0);
 865         }
 866
 867         /* allocate 3215 request structures */
 868         raw3215_freelist = NULL;
 869         spin_lock_init(&raw3215_freelist_lock);
 870         for (i = 0; i < NR_3215_REQ; i++) {
 871                 req = (struct raw3215_req *) alloc_bootmem_low(sizeof(struct raw3215_req));
 872                 req->next = raw3215_freelist;
 873                 raw3215_freelist = req;
 874         }
 875
 876         cdev = ccw_device_probe_console();
 877         if (!cdev)
 878                 return -ENODEV;
 879
 880         raw3215[0] = raw = (struct raw3215_info *)
 881                 alloc_bootmem_low(sizeof(struct raw3215_info));
 882         memset(raw, 0, sizeof(struct raw3215_info));
 883         raw->buffer = (char *) alloc_bootmem_low(RAW3215_BUFFER_SIZE);
 884         raw->inbuf = (char *) alloc_bootmem_low(RAW3215_INBUF_SIZE);
 885         raw->cdev = cdev;
 886         raw->lock = get_ccwdev_lock(cdev);
 887         cdev->dev.driver_data = raw;
 888         cdev->handler = raw3215_irq;
 889
 890         raw->flags |= RAW3215_FIXED;
 891         tasklet_init(&raw->tasklet,
 892                      (void (*)(unsigned long)) raw3215_tasklet,
 893                      (unsigned long) raw);
 894         init_waitqueue_head(&raw->empty_wait);
 895
 896         /* Request the console irq */
 897         if (raw3215_startup(raw) != 0) {
 898                 free_bootmem((unsigned long) raw->inbuf, RAW3215_INBUF_SIZE);
 899                 free_bootmem((unsigned long) raw->buffer, RAW3215_BUFFER_SIZE);
 900                 free_bootmem((unsigned long) raw, sizeof(struct raw3215_info));
 901                 raw3215[0] = NULL;
 902                 printk("Couldn't find a 3215 console device\n");
 903                 return -ENODEV;
 904         }
 905         register_console(&con3215);
 906         return 0;
 907 }
 908 console_initcall(con3215_init);
 909 #endif
 910
 911 /*
 912  * tty3215_open
 913  *
 914  * This routine is called whenever a 3215 tty is opened.
 915  */
 916 static int
 917 tty3215_open(struct tty_struct *tty, struct file * filp)
 918 {
 919         struct raw3215_info *raw;
 920         int retval, line;
 921
 922         line = tty->index;
 923         if ((line < 0) || (line >= NR_3215))
 924                 return -ENODEV;
 925
 926         raw = raw3215[line];
 927         if (raw == NULL)
 928                 return -ENODEV;
 929
 930         tty->driver_data = raw;
 931         raw->tty = tty;
 932
 933         tty->low_latency = 0;  /* don't use bottom half for pushing chars */
 934         /*
 935          * Start up 3215 device
 936          */
 937         retval = raw3215_startup(raw);
 938         if (retval)
 939                 return retval;
 940
 941         return 0;
 942 }
 943
 944 /*
 945  * tty3215_close()
 946  *
 947  * This routine is called when the 3215 tty is closed. We wait
 948  * for the remaining request to be completed. Then we clean up.
 949  */
 950 static void
 951 tty3215_close(struct tty_struct *tty, struct file * filp)
 952 {
 953         struct raw3215_info *raw;
 954
 955         raw = (struct raw3215_info *) tty->driver_data;
 956         if (raw == NULL || tty->count > 1)
 957                 return;
 958         tty->closing = 1;
 959         /* Shutdown the terminal */
 960         raw3215_shutdown(raw);
 961         tty->closing = 0;
 962         raw->tty = NULL;
 963 }
 964
 965 /*
 966  * Returns the amount of free space in the output buffer.
 967  */
 968 static int
 969 tty3215_write_room(struct tty_struct *tty)
 970 {
 971         struct raw3215_info *raw;
 972
 973         raw = (struct raw3215_info *) tty->driver_data;
 974
 975         /* Subtract TAB_STOP_SIZE to allow for a tab, 8 <<< 64K */
 976         if ((RAW3215_BUFFER_SIZE - raw->count - TAB_STOP_SIZE) >= 0)
 977                 return RAW3215_BUFFER_SIZE - raw->count - TAB_STOP_SIZE;
 978         else
 979                 return 0;
 980 }
 981
 982 /*
 983  * String write routine for 3215 ttys
 984  */
 985 static int
 986 tty3215_write(struct tty_struct * tty, int from_user,
 987               const unsigned char *buf, int count)
 988 {
 989         struct raw3215_info *raw;
 990         int length, ret;
 991
 992         if (!tty)
 993                 return 0;
 994         raw = (struct raw3215_info *) tty->driver_data;
 995         if (!from_user) {
 996                 raw3215_write(raw, buf, count);
 997                 return count;
 998         }
 999         ret = 0;
1000         while (count > 0) {
1001                 length = count < 80 ? count : 80;
1002                 length -= copy_from_user(raw->ubuffer,
1003                                 (const unsigned char __user *)buf, length);
1004                 if (length == 0) {
1005                         if (!ret)
1006                                 ret = -EFAULT;
1007                         break;
1008                 }
1009                 raw3215_write(raw, raw->ubuffer, count);
1010                 buf += length;
1011                 count -= length;
1012                 ret += length;
1013         }
1014         return ret;
1015 }
1016
1017 /*
1018  * Put character routine for 3215 ttys
1019  */
1020 static void
1021 tty3215_put_char(struct tty_struct *tty, unsigned char ch)
1022 {
1023         struct raw3215_info *raw;
1024
1025         if (!tty)
1026                 return;
1027         raw = (struct raw3215_info *) tty->driver_data;
1028         raw3215_putchar(raw, ch);
1029 }
1030
1031 static void
1032 tty3215_flush_chars(struct tty_struct *tty)
1033 {
1034 }
1035
1036 /*
1037  * Returns the number of characters in the output buffer
1038  */
1039 static int
1040 tty3215_chars_in_buffer(struct tty_struct *tty)
1041 {
1042         struct raw3215_info *raw;
1043
1044         raw = (struct raw3215_info *) tty->driver_data;
1045         return raw->count;
1046 }
1047
1048 static void
1049 tty3215_flush_buffer(struct tty_struct *tty)
1050 {
1051         struct raw3215_info *raw;
1052
1053         raw = (struct raw3215_info *) tty->driver_data;
1054         raw3215_flush_buffer(raw);
1055         tty_wakeup(tty);
1056 }
1057
1058 /*
1059  * Currently we don't have any io controls for 3215 ttys
1060  */
1061 static int
1062 tty3215_ioctl(struct tty_struct *tty, struct file * file,
1063               unsigned int cmd, unsigned long arg)
1064 {
1065         if (tty->flags & (1 << TTY_IO_ERROR))
1066                 return -EIO;
1067
1068         switch (cmd) {
1069         default:
1070                 return -ENOIOCTLCMD;
1071         }
1072         return 0;
1073 }
1074
1075 /*
1076  * Disable reading from a 3215 tty
1077  */
1078 static void
1079 tty3215_throttle(struct tty_struct * tty)
1080 {
1081         struct raw3215_info *raw;
1082
1083         raw = (struct raw3215_info *) tty->driver_data;
1084         raw->flags |= RAW3215_THROTTLED;
1085 }
1086
1087 /*
1088  * Enable reading from a 3215 tty
1089  */
1090 static void
1091 tty3215_unthrottle(struct tty_struct * tty)
1092 {
1093         struct raw3215_info *raw;
1094         unsigned long flags;
1095
1096         raw = (struct raw3215_info *) tty->driver_data;
1097         if (raw->flags & RAW3215_THROTTLED) {
1098                 spin_lock_irqsave(raw->lock, flags);
1099                 raw->flags &= ~RAW3215_THROTTLED;
1100                 raw3215_try_io(raw);
1101                 spin_unlock_irqrestore(raw->lock, flags);
1102         }
1103 }
1104
1105 /*
1106  * Disable writing to a 3215 tty
1107  */
1108 static void
1109 tty3215_stop(struct tty_struct *tty)
1110 {
1111         struct raw3215_info *raw;
1112
1113         raw = (struct raw3215_info *) tty->driver_data;
1114         raw->flags |= RAW3215_STOPPED;
1115 }
1116
1117 /*
1118  * Enable writing to a 3215 tty
1119  */
1120 static void
1121 tty3215_start(struct tty_struct *tty)
1122 {
1123         struct raw3215_info *raw;
1124         unsigned long flags;
1125
1126         raw = (struct raw3215_info *) tty->driver_data;
1127         if (raw->flags & RAW3215_STOPPED) {
1128                 spin_lock_irqsave(raw->lock, flags);
1129                 raw->flags &= ~RAW3215_STOPPED;
1130                 raw3215_try_io(raw);
1131                 spin_unlock_irqrestore(raw->lock, flags);
1132         }
1133 }
1134
1135 static struct tty_operations tty3215_ops = {
1136         .open = tty3215_open,
1137         .close = tty3215_close,
1138         .write = tty3215_write,
1139         .put_char = tty3215_put_char,
1140         .flush_chars = tty3215_flush_chars,
1141         .write_room = tty3215_write_room,
1142         .chars_in_buffer = tty3215_chars_in_buffer,
1143         .flush_buffer = tty3215_flush_buffer,
1144         .ioctl = tty3215_ioctl,
1145         .throttle = tty3215_throttle,
1146         .unthrottle = tty3215_unthrottle,
1147         .stop = tty3215_stop,
1148         .start = tty3215_start,
1149 };
1150
1151 /*
1152  * 3215 tty registration code called from tty_init().
1153  * Most kernel services (incl. kmalloc) are available at this poimt.
1154  */
1155 int __init
1156 tty3215_init(void)
1157 {
1158         struct tty_driver *driver;
1159         int ret;
1160
1161         if (!CONSOLE_IS_3215)
1162                 return 0;
1163
1164         driver = alloc_tty_driver(NR_3215);
1165         if (!driver)
1166                 return -ENOMEM;
1167
1168         ret = ccw_driver_register(&raw3215_ccw_driver);
1169         if (ret) {
1170                 put_tty_driver(driver);
1171                 return ret;
1172         }
1173         /*
1174          * Initialize the tty_driver structure
1175          * Entries in tty3215_driver that are NOT initialized:
1176          * proc_entry, set_termios, flush_buffer, set_ldisc, write_proc
1177          */
1178
1179         driver->owner = THIS_MODULE;
1180         driver->driver_name = "tty3215";
1181         driver->name = "ttyS";
1182         driver->major = TTY_MAJOR;
1183         driver->minor_start = 64;
1184         driver->type = TTY_DRIVER_TYPE_SYSTEM;
1185         driver->subtype = SYSTEM_TYPE_TTY;
1186         driver->init_termios = tty_std_termios;
1187         driver->init_termios.c_iflag = IGNBRK | IGNPAR;
1188         driver->init_termios.c_oflag = ONLCR | XTABS;
1189         driver->init_termios.c_lflag = ISIG;
1190         driver->flags = TTY_DRIVER_REAL_RAW;
1191         tty_set_operations(driver, &tty3215_ops);
1192         ret = tty_register_driver(driver);
1193         if (ret) {
1194                 printk("Couldn't register tty3215 driver\n");
1195                 put_tty_driver(driver);
1196                 return ret;
1197         }
1198         tty3215_driver = driver;
1199         return 0;
1200 }
1201
1202 static void __exit
1203 tty3215_exit(void)
1204 {
1205         tty_unregister_driver(tty3215_driver);
1206         put_tty_driver(tty3215_driver);
1207         ccw_driver_unregister(&raw3215_ccw_driver);
1208 }
1209
1210 module_init(tty3215_init);
1211 module_exit(tty3215_exit);