1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * 3215 line mode terminal driver. 4 * 5 * Copyright IBM Corp. 1999, 2009 6 * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com> 7 * 8 * Updated: 9 * Aug-2000: Added tab support 10 * Dan Morrison, IBM Corporation <dmorriso@cse.buffalo.edu> 11 */ 12 13 #include <linux/types.h> 14 #include <linux/kdev_t.h> 15 #include <linux/tty.h> 16 #include <linux/tty_flip.h> 17 #include <linux/vt_kern.h> 18 #include <linux/init.h> 19 #include <linux/console.h> 20 #include <linux/interrupt.h> 21 #include <linux/err.h> 22 #include <linux/panic_notifier.h> 23 #include <linux/reboot.h> 24 #include <linux/serial.h> /* ASYNC_* flags */ 25 #include <linux/slab.h> 26 #include <asm/ccwdev.h> 27 #include <asm/cio.h> 28 #include <asm/io.h> 29 #include <asm/ebcdic.h> 30 #include <linux/uaccess.h> 31 #include <asm/delay.h> 32 #include <asm/cpcmd.h> 33 #include <asm/setup.h> 34 35 #include "ctrlchar.h" 36 37 #define NR_3215 1 38 #define NR_3215_REQ (4*NR_3215) 39 #define RAW3215_BUFFER_SIZE 65536 /* output buffer size */ 40 #define RAW3215_INBUF_SIZE 256 /* input buffer size */ 41 #define RAW3215_MIN_SPACE 128 /* minimum free space for wakeup */ 42 #define RAW3215_MIN_WRITE 1024 /* min. length for immediate output */ 43 #define RAW3215_MAX_BYTES 3968 /* max. bytes to write with one ssch */ 44 #define RAW3215_MAX_NEWLINE 50 /* max. lines to write with one ssch */ 45 #define RAW3215_NR_CCWS 3 46 #define RAW3215_TIMEOUT HZ/10 /* time for delayed output */ 47 48 #define RAW3215_FIXED 1 /* 3215 console device is not be freed */ 49 #define RAW3215_WORKING 4 /* set if a request is being worked on */ 50 #define RAW3215_THROTTLED 8 /* set if reading is disabled */ 51 #define RAW3215_STOPPED 16 /* set if writing is disabled */ 52 #define RAW3215_TIMER_RUNS 64 /* set if the output delay timer is on */ 53 #define RAW3215_FLUSHING 128 /* set to flush buffer (no delay) */ 54 55 #define TAB_STOP_SIZE 8 /* tab stop size */ 56 57 /* 58 * Request types for a 3215 device 59 */ 60 enum raw3215_type { 61 RAW3215_FREE, RAW3215_READ, RAW3215_WRITE 62 }; 63 64 /* 65 * Request structure for a 3215 device 66 */ 67 struct raw3215_req { 68 enum raw3215_type type; /* type of the request */ 69 int start, len; /* start index & len in output buffer */ 70 int delayable; /* indication to wait for more data */ 71 int residual; /* residual count for read request */ 72 struct ccw1 ccws[RAW3215_NR_CCWS]; /* space for the channel program */ 73 struct raw3215_info *info; /* pointer to main structure */ 74 struct raw3215_req *next; /* pointer to next request */ 75 } __attribute__ ((aligned(8))); 76 77 struct raw3215_info { 78 struct tty_port port; 79 struct ccw_device *cdev; /* device for tty driver */ 80 spinlock_t *lock; /* pointer to irq lock */ 81 int flags; /* state flags */ 82 char *buffer; /* pointer to output buffer */ 83 char *inbuf; /* pointer to input buffer */ 84 int head; /* first free byte in output buffer */ 85 int count; /* number of bytes in output buffer */ 86 int written; /* number of bytes in write requests */ 87 struct raw3215_req *queued_read; /* pointer to queued read requests */ 88 struct raw3215_req *queued_write;/* pointer to queued write requests */ 89 wait_queue_head_t empty_wait; /* wait queue for flushing */ 90 struct timer_list timer; /* timer for delayed output */ 91 int line_pos; /* position on the line (for tabs) */ 92 char ubuffer[80]; /* copy_from_user buffer */ 93 }; 94 95 /* array of 3215 devices structures */ 96 static struct raw3215_info *raw3215[NR_3215]; 97 /* spinlock to protect the raw3215 array */ 98 static DEFINE_SPINLOCK(raw3215_device_lock); 99 /* list of free request structures */ 100 static struct raw3215_req *raw3215_freelist; 101 /* spinlock to protect free list */ 102 static DEFINE_SPINLOCK(raw3215_freelist_lock); 103 104 static struct tty_driver *tty3215_driver; 105 static bool con3215_drop = true; 106 107 /* 108 * Get a request structure from the free list 109 */ 110 static inline struct raw3215_req *raw3215_alloc_req(void) 111 { 112 struct raw3215_req *req; 113 unsigned long flags; 114 115 spin_lock_irqsave(&raw3215_freelist_lock, flags); 116 req = raw3215_freelist; 117 raw3215_freelist = req->next; 118 spin_unlock_irqrestore(&raw3215_freelist_lock, flags); 119 return req; 120 } 121 122 /* 123 * Put a request structure back to the free list 124 */ 125 static inline void raw3215_free_req(struct raw3215_req *req) 126 { 127 unsigned long flags; 128 129 if (req->type == RAW3215_FREE) 130 return; /* don't free a free request */ 131 req->type = RAW3215_FREE; 132 spin_lock_irqsave(&raw3215_freelist_lock, flags); 133 req->next = raw3215_freelist; 134 raw3215_freelist = req; 135 spin_unlock_irqrestore(&raw3215_freelist_lock, flags); 136 } 137 138 /* 139 * Set up a read request that reads up to 160 byte from the 3215 device. 140 * If there is a queued read request it is used, but that shouldn't happen 141 * because a 3215 terminal won't accept a new read before the old one is 142 * completed. 143 */ 144 static void raw3215_mk_read_req(struct raw3215_info *raw) 145 { 146 struct raw3215_req *req; 147 struct ccw1 *ccw; 148 149 /* there can only be ONE read request at a time */ 150 req = raw->queued_read; 151 if (req == NULL) { 152 /* no queued read request, use new req structure */ 153 req = raw3215_alloc_req(); 154 req->type = RAW3215_READ; 155 req->info = raw; 156 raw->queued_read = req; 157 } 158 159 ccw = req->ccws; 160 ccw->cmd_code = 0x0A; /* read inquiry */ 161 ccw->flags = 0x20; /* ignore incorrect length */ 162 ccw->count = 160; 163 ccw->cda = (__u32)__pa(raw->inbuf); 164 } 165 166 /* 167 * Set up a write request with the information from the main structure. 168 * A ccw chain is created that writes as much as possible from the output 169 * buffer to the 3215 device. If a queued write exists it is replaced by 170 * the new, probably lengthened request. 171 */ 172 static void raw3215_mk_write_req(struct raw3215_info *raw) 173 { 174 struct raw3215_req *req; 175 struct ccw1 *ccw; 176 int len, count, ix, lines; 177 178 if (raw->count <= raw->written) 179 return; 180 /* check if there is a queued write request */ 181 req = raw->queued_write; 182 if (req == NULL) { 183 /* no queued write request, use new req structure */ 184 req = raw3215_alloc_req(); 185 req->type = RAW3215_WRITE; 186 req->info = raw; 187 raw->queued_write = req; 188 } else { 189 raw->written -= req->len; 190 } 191 192 ccw = req->ccws; 193 req->start = (raw->head - raw->count + raw->written) & 194 (RAW3215_BUFFER_SIZE - 1); 195 /* 196 * now we have to count newlines. We can at max accept 197 * RAW3215_MAX_NEWLINE newlines in a single ssch due to 198 * a restriction in VM 199 */ 200 lines = 0; 201 ix = req->start; 202 while (lines < RAW3215_MAX_NEWLINE && ix != raw->head) { 203 if (raw->buffer[ix] == 0x15) 204 lines++; 205 ix = (ix + 1) & (RAW3215_BUFFER_SIZE - 1); 206 } 207 len = ((ix - 1 - req->start) & (RAW3215_BUFFER_SIZE - 1)) + 1; 208 if (len > RAW3215_MAX_BYTES) 209 len = RAW3215_MAX_BYTES; 210 req->len = len; 211 raw->written += len; 212 213 /* set the indication if we should try to enlarge this request */ 214 req->delayable = (ix == raw->head) && (len < RAW3215_MIN_WRITE); 215 216 ix = req->start; 217 while (len > 0) { 218 if (ccw > req->ccws) 219 ccw[-1].flags |= 0x40; /* use command chaining */ 220 ccw->cmd_code = 0x01; /* write, auto carrier return */ 221 ccw->flags = 0x20; /* ignore incorrect length ind. */ 222 ccw->cda = (__u32)__pa(raw->buffer + ix); 223 count = len; 224 if (ix + count > RAW3215_BUFFER_SIZE) 225 count = RAW3215_BUFFER_SIZE - ix; 226 ccw->count = count; 227 len -= count; 228 ix = (ix + count) & (RAW3215_BUFFER_SIZE - 1); 229 ccw++; 230 } 231 /* 232 * Add a NOP to the channel program. 3215 devices are purely 233 * emulated and its much better to avoid the channel end 234 * interrupt in this case. 235 */ 236 if (ccw > req->ccws) 237 ccw[-1].flags |= 0x40; /* use command chaining */ 238 ccw->cmd_code = 0x03; /* NOP */ 239 ccw->flags = 0; 240 ccw->cda = 0; 241 ccw->count = 1; 242 } 243 244 /* 245 * Start a read or a write request 246 */ 247 static void raw3215_start_io(struct raw3215_info *raw) 248 { 249 struct raw3215_req *req; 250 int res; 251 252 req = raw->queued_read; 253 if (req != NULL && 254 !(raw->flags & (RAW3215_WORKING | RAW3215_THROTTLED))) { 255 /* dequeue request */ 256 raw->queued_read = NULL; 257 res = ccw_device_start(raw->cdev, req->ccws, 258 (unsigned long) req, 0, 0); 259 if (res != 0) { 260 /* do_IO failed, put request back to queue */ 261 raw->queued_read = req; 262 } else { 263 raw->flags |= RAW3215_WORKING; 264 } 265 } 266 req = raw->queued_write; 267 if (req != NULL && 268 !(raw->flags & (RAW3215_WORKING | RAW3215_STOPPED))) { 269 /* dequeue request */ 270 raw->queued_write = NULL; 271 res = ccw_device_start(raw->cdev, req->ccws, 272 (unsigned long) req, 0, 0); 273 if (res != 0) { 274 /* do_IO failed, put request back to queue */ 275 raw->queued_write = req; 276 } else { 277 raw->flags |= RAW3215_WORKING; 278 } 279 } 280 } 281 282 /* 283 * Function to start a delayed output after RAW3215_TIMEOUT seconds 284 */ 285 static void raw3215_timeout(struct timer_list *t) 286 { 287 struct raw3215_info *raw = from_timer(raw, t, timer); 288 unsigned long flags; 289 290 spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags); 291 raw->flags &= ~RAW3215_TIMER_RUNS; 292 raw3215_mk_write_req(raw); 293 raw3215_start_io(raw); 294 if ((raw->queued_read || raw->queued_write) && 295 !(raw->flags & RAW3215_WORKING) && 296 !(raw->flags & RAW3215_TIMER_RUNS)) { 297 raw->timer.expires = RAW3215_TIMEOUT + jiffies; 298 add_timer(&raw->timer); 299 raw->flags |= RAW3215_TIMER_RUNS; 300 } 301 spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags); 302 } 303 304 /* 305 * Function to conditionally start an IO. A read is started immediately, 306 * a write is only started immediately if the flush flag is on or the 307 * amount of data is bigger than RAW3215_MIN_WRITE. If a write is not 308 * done immediately a timer is started with a delay of RAW3215_TIMEOUT. 309 */ 310 static inline void raw3215_try_io(struct raw3215_info *raw) 311 { 312 if (!tty_port_initialized(&raw->port)) 313 return; 314 if (raw->queued_read != NULL) 315 raw3215_start_io(raw); 316 else if (raw->queued_write != NULL) { 317 if ((raw->queued_write->delayable == 0) || 318 (raw->flags & RAW3215_FLUSHING)) { 319 /* execute write requests bigger than minimum size */ 320 raw3215_start_io(raw); 321 } 322 } 323 if ((raw->queued_read || raw->queued_write) && 324 !(raw->flags & RAW3215_WORKING) && 325 !(raw->flags & RAW3215_TIMER_RUNS)) { 326 raw->timer.expires = RAW3215_TIMEOUT + jiffies; 327 add_timer(&raw->timer); 328 raw->flags |= RAW3215_TIMER_RUNS; 329 } 330 } 331 332 /* 333 * Try to start the next IO and wake up processes waiting on the tty. 334 */ 335 static void raw3215_next_io(struct raw3215_info *raw, struct tty_struct *tty) 336 { 337 raw3215_mk_write_req(raw); 338 raw3215_try_io(raw); 339 if (tty && RAW3215_BUFFER_SIZE - raw->count >= RAW3215_MIN_SPACE) 340 tty_wakeup(tty); 341 } 342 343 /* 344 * Interrupt routine, called from common io layer 345 */ 346 static void raw3215_irq(struct ccw_device *cdev, unsigned long intparm, 347 struct irb *irb) 348 { 349 struct raw3215_info *raw; 350 struct raw3215_req *req; 351 struct tty_struct *tty; 352 int cstat, dstat; 353 int count; 354 355 raw = dev_get_drvdata(&cdev->dev); 356 req = (struct raw3215_req *) intparm; 357 tty = tty_port_tty_get(&raw->port); 358 cstat = irb->scsw.cmd.cstat; 359 dstat = irb->scsw.cmd.dstat; 360 if (cstat != 0) 361 raw3215_next_io(raw, tty); 362 if (dstat & 0x01) { /* we got a unit exception */ 363 dstat &= ~0x01; /* we can ignore it */ 364 } 365 switch (dstat) { 366 case 0x80: 367 if (cstat != 0) 368 break; 369 /* Attention interrupt, someone hit the enter key */ 370 raw3215_mk_read_req(raw); 371 raw3215_next_io(raw, tty); 372 break; 373 case 0x08: 374 case 0x0C: 375 /* Channel end interrupt. */ 376 if ((raw = req->info) == NULL) 377 goto put_tty; /* That shouldn't happen ... */ 378 if (req->type == RAW3215_READ) { 379 /* store residual count, then wait for device end */ 380 req->residual = irb->scsw.cmd.count; 381 } 382 if (dstat == 0x08) 383 break; 384 fallthrough; 385 case 0x04: 386 /* Device end interrupt. */ 387 if ((raw = req->info) == NULL) 388 goto put_tty; /* That shouldn't happen ... */ 389 if (req->type == RAW3215_READ && tty != NULL) { 390 unsigned int cchar; 391 392 count = 160 - req->residual; 393 EBCASC(raw->inbuf, count); 394 cchar = ctrlchar_handle(raw->inbuf, count, tty); 395 switch (cchar & CTRLCHAR_MASK) { 396 case CTRLCHAR_SYSRQ: 397 break; 398 399 case CTRLCHAR_CTRL: 400 tty_insert_flip_char(&raw->port, cchar, 401 TTY_NORMAL); 402 tty_flip_buffer_push(&raw->port); 403 break; 404 405 case CTRLCHAR_NONE: 406 if (count < 2 || 407 (strncmp(raw->inbuf+count-2, "\252n", 2) && 408 strncmp(raw->inbuf+count-2, "^n", 2)) ) { 409 /* add the auto \n */ 410 raw->inbuf[count] = '\n'; 411 count++; 412 } else 413 count -= 2; 414 tty_insert_flip_string(&raw->port, raw->inbuf, 415 count); 416 tty_flip_buffer_push(&raw->port); 417 break; 418 } 419 } else if (req->type == RAW3215_WRITE) { 420 raw->count -= req->len; 421 raw->written -= req->len; 422 } 423 raw->flags &= ~RAW3215_WORKING; 424 raw3215_free_req(req); 425 /* check for empty wait */ 426 if (waitqueue_active(&raw->empty_wait) && 427 raw->queued_write == NULL && 428 raw->queued_read == NULL) { 429 wake_up_interruptible(&raw->empty_wait); 430 } 431 raw3215_next_io(raw, tty); 432 break; 433 default: 434 /* Strange interrupt, I'll do my best to clean up */ 435 if (req != NULL && req->type != RAW3215_FREE) { 436 if (req->type == RAW3215_WRITE) { 437 raw->count -= req->len; 438 raw->written -= req->len; 439 } 440 raw->flags &= ~RAW3215_WORKING; 441 raw3215_free_req(req); 442 } 443 raw3215_next_io(raw, tty); 444 } 445 put_tty: 446 tty_kref_put(tty); 447 } 448 449 /* 450 * Need to drop data to avoid blocking. Drop as much data as possible. 451 * This is unqueued part in the buffer and the queued part in the request. 452 * Also adjust the head position to append new data and set count 453 * accordingly. 454 * 455 * Return number of bytes available in buffer. 456 */ 457 static unsigned int raw3215_drop(struct raw3215_info *raw) 458 { 459 struct raw3215_req *req; 460 461 req = raw->queued_write; 462 if (req) { 463 /* Drop queued data and delete request */ 464 raw->written -= req->len; 465 raw3215_free_req(req); 466 raw->queued_write = NULL; 467 } 468 raw->head = (raw->head - raw->count + raw->written) & 469 (RAW3215_BUFFER_SIZE - 1); 470 raw->count = raw->written; 471 472 return RAW3215_BUFFER_SIZE - raw->count; 473 } 474 475 /* 476 * Wait until length bytes are available int the output buffer. 477 * If drop mode is active and wait condition holds true, start dropping 478 * data. 479 * Has to be called with the s390irq lock held. Can be called 480 * disabled. 481 */ 482 static unsigned int raw3215_make_room(struct raw3215_info *raw, 483 unsigned int length, bool drop) 484 { 485 while (RAW3215_BUFFER_SIZE - raw->count < length) { 486 if (drop) 487 return raw3215_drop(raw); 488 489 /* there might be a request pending */ 490 raw->flags |= RAW3215_FLUSHING; 491 raw3215_mk_write_req(raw); 492 raw3215_try_io(raw); 493 raw->flags &= ~RAW3215_FLUSHING; 494 #ifdef CONFIG_TN3215_CONSOLE 495 ccw_device_wait_idle(raw->cdev); 496 #endif 497 /* Enough room freed up ? */ 498 if (RAW3215_BUFFER_SIZE - raw->count >= length) 499 break; 500 /* there might be another cpu waiting for the lock */ 501 spin_unlock(get_ccwdev_lock(raw->cdev)); 502 udelay(100); 503 spin_lock(get_ccwdev_lock(raw->cdev)); 504 } 505 return length; 506 } 507 508 #define RAW3215_COUNT 1 509 #define RAW3215_STORE 2 510 511 /* 512 * Add text to console buffer. Find tabs in input and calculate size 513 * including tab replacement. 514 * This function operates in 2 different modes, depending on parameter 515 * opmode: 516 * RAW3215_COUNT: Get the size needed for the input string with 517 * proper tab replacement calculation. 518 * Return value is the number of bytes required to store the 519 * input. However no data is actually stored. 520 * The parameter todrop is not used. 521 * RAW3215_STORE: Add data to the console buffer. The parameter todrop is 522 * valid and contains the number of bytes to be dropped from head of 523 * string without blocking. 524 * Return value is the number of bytes copied. 525 */ 526 static unsigned int raw3215_addtext(const char *str, unsigned int length, 527 struct raw3215_info *raw, int opmode, 528 unsigned int todrop) 529 { 530 unsigned int c, ch, i, blanks, expanded_size = 0; 531 unsigned int column = raw->line_pos; 532 533 if (opmode == RAW3215_COUNT) 534 todrop = 0; 535 536 for (c = 0; c < length; ++c) { 537 blanks = 1; 538 ch = str[c]; 539 540 switch (ch) { 541 case '\n': 542 expanded_size++; 543 column = 0; 544 break; 545 case '\t': 546 blanks = TAB_STOP_SIZE - (column % TAB_STOP_SIZE); 547 column += blanks; 548 expanded_size += blanks; 549 ch = ' '; 550 break; 551 default: 552 expanded_size++; 553 column++; 554 break; 555 } 556 557 if (opmode == RAW3215_COUNT) 558 continue; 559 if (todrop && expanded_size < todrop) /* Drop head data */ 560 continue; 561 for (i = 0; i < blanks; i++) { 562 raw->buffer[raw->head] = (char)_ascebc[(int)ch]; 563 raw->head = (raw->head + 1) & (RAW3215_BUFFER_SIZE - 1); 564 raw->count++; 565 } 566 raw->line_pos = column; 567 } 568 return expanded_size - todrop; 569 } 570 571 /* 572 * String write routine for 3215 devices 573 */ 574 static void raw3215_write(struct raw3215_info *raw, const char *str, 575 unsigned int length) 576 { 577 unsigned int count, avail; 578 unsigned long flags; 579 580 spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags); 581 582 count = raw3215_addtext(str, length, raw, RAW3215_COUNT, 0); 583 584 avail = raw3215_make_room(raw, count, con3215_drop); 585 if (avail) { 586 raw3215_addtext(str, length, raw, RAW3215_STORE, 587 count - avail); 588 } 589 if (!(raw->flags & RAW3215_WORKING)) { 590 raw3215_mk_write_req(raw); 591 /* start or queue request */ 592 raw3215_try_io(raw); 593 } 594 spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags); 595 } 596 597 /* 598 * Put character routine for 3215 devices 599 */ 600 static void raw3215_putchar(struct raw3215_info *raw, unsigned char ch) 601 { 602 raw3215_write(raw, &ch, 1); 603 } 604 605 /* 606 * Flush routine, it simply sets the flush flag and tries to start 607 * pending IO. 608 */ 609 static void raw3215_flush_buffer(struct raw3215_info *raw) 610 { 611 unsigned long flags; 612 613 spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags); 614 if (raw->count > 0) { 615 raw->flags |= RAW3215_FLUSHING; 616 raw3215_try_io(raw); 617 raw->flags &= ~RAW3215_FLUSHING; 618 } 619 spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags); 620 } 621 622 /* 623 * Fire up a 3215 device. 624 */ 625 static int raw3215_startup(struct raw3215_info *raw) 626 { 627 unsigned long flags; 628 629 if (tty_port_initialized(&raw->port)) 630 return 0; 631 raw->line_pos = 0; 632 tty_port_set_initialized(&raw->port, 1); 633 spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags); 634 raw3215_try_io(raw); 635 spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags); 636 637 return 0; 638 } 639 640 /* 641 * Shutdown a 3215 device. 642 */ 643 static void raw3215_shutdown(struct raw3215_info *raw) 644 { 645 DECLARE_WAITQUEUE(wait, current); 646 unsigned long flags; 647 648 if (!tty_port_initialized(&raw->port) || (raw->flags & RAW3215_FIXED)) 649 return; 650 /* Wait for outstanding requests, then free irq */ 651 spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags); 652 if ((raw->flags & RAW3215_WORKING) || 653 raw->queued_write != NULL || 654 raw->queued_read != NULL) { 655 add_wait_queue(&raw->empty_wait, &wait); 656 set_current_state(TASK_INTERRUPTIBLE); 657 spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags); 658 schedule(); 659 spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags); 660 remove_wait_queue(&raw->empty_wait, &wait); 661 set_current_state(TASK_RUNNING); 662 tty_port_set_initialized(&raw->port, 1); 663 } 664 spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags); 665 } 666 667 static struct raw3215_info *raw3215_alloc_info(void) 668 { 669 struct raw3215_info *info; 670 671 info = kzalloc(sizeof(struct raw3215_info), GFP_KERNEL | GFP_DMA); 672 if (!info) 673 return NULL; 674 675 info->buffer = kzalloc(RAW3215_BUFFER_SIZE, GFP_KERNEL | GFP_DMA); 676 info->inbuf = kzalloc(RAW3215_INBUF_SIZE, GFP_KERNEL | GFP_DMA); 677 if (!info->buffer || !info->inbuf) { 678 kfree(info->inbuf); 679 kfree(info->buffer); 680 kfree(info); 681 return NULL; 682 } 683 684 timer_setup(&info->timer, raw3215_timeout, 0); 685 init_waitqueue_head(&info->empty_wait); 686 tty_port_init(&info->port); 687 688 return info; 689 } 690 691 static void raw3215_free_info(struct raw3215_info *raw) 692 { 693 kfree(raw->inbuf); 694 kfree(raw->buffer); 695 tty_port_destroy(&raw->port); 696 kfree(raw); 697 } 698 699 static int raw3215_probe(struct ccw_device *cdev) 700 { 701 struct raw3215_info *raw; 702 int line; 703 704 /* Console is special. */ 705 if (raw3215[0] && (raw3215[0] == dev_get_drvdata(&cdev->dev))) 706 return 0; 707 708 raw = raw3215_alloc_info(); 709 if (raw == NULL) 710 return -ENOMEM; 711 712 raw->cdev = cdev; 713 dev_set_drvdata(&cdev->dev, raw); 714 cdev->handler = raw3215_irq; 715 716 spin_lock(&raw3215_device_lock); 717 for (line = 0; line < NR_3215; line++) { 718 if (!raw3215[line]) { 719 raw3215[line] = raw; 720 break; 721 } 722 } 723 spin_unlock(&raw3215_device_lock); 724 if (line == NR_3215) { 725 raw3215_free_info(raw); 726 return -ENODEV; 727 } 728 729 return 0; 730 } 731 732 static void raw3215_remove(struct ccw_device *cdev) 733 { 734 struct raw3215_info *raw; 735 unsigned int line; 736 737 ccw_device_set_offline(cdev); 738 raw = dev_get_drvdata(&cdev->dev); 739 if (raw) { 740 spin_lock(&raw3215_device_lock); 741 for (line = 0; line < NR_3215; line++) 742 if (raw3215[line] == raw) 743 break; 744 raw3215[line] = NULL; 745 spin_unlock(&raw3215_device_lock); 746 dev_set_drvdata(&cdev->dev, NULL); 747 raw3215_free_info(raw); 748 } 749 } 750 751 static int raw3215_set_online(struct ccw_device *cdev) 752 { 753 struct raw3215_info *raw; 754 755 raw = dev_get_drvdata(&cdev->dev); 756 if (!raw) 757 return -ENODEV; 758 759 return raw3215_startup(raw); 760 } 761 762 static int raw3215_set_offline(struct ccw_device *cdev) 763 { 764 struct raw3215_info *raw; 765 766 raw = dev_get_drvdata(&cdev->dev); 767 if (!raw) 768 return -ENODEV; 769 770 raw3215_shutdown(raw); 771 772 return 0; 773 } 774 775 static struct ccw_device_id raw3215_id[] = { 776 { CCW_DEVICE(0x3215, 0) }, 777 { /* end of list */ }, 778 }; 779 780 static ssize_t con_drop_store(struct device_driver *dev, const char *buf, size_t count) 781 { 782 bool drop; 783 int rc; 784 785 rc = kstrtobool(buf, &drop); 786 if (!rc) 787 con3215_drop = drop; 788 return rc ?: count; 789 } 790 791 static ssize_t con_drop_show(struct device_driver *dev, char *buf) 792 { 793 return sysfs_emit(buf, "%d\n", con3215_drop ? 1 : 0); 794 } 795 796 static DRIVER_ATTR_RW(con_drop); 797 798 static struct attribute *con3215_drv_attrs[] = { 799 &driver_attr_con_drop.attr, 800 NULL, 801 }; 802 803 static struct attribute_group con3215_drv_attr_group = { 804 .attrs = con3215_drv_attrs, 805 NULL, 806 }; 807 808 static const struct attribute_group *con3215_drv_attr_groups[] = { 809 &con3215_drv_attr_group, 810 NULL, 811 }; 812 813 static struct ccw_driver raw3215_ccw_driver = { 814 .driver = { 815 .name = "3215", 816 .groups = con3215_drv_attr_groups, 817 .owner = THIS_MODULE, 818 }, 819 .ids = raw3215_id, 820 .probe = &raw3215_probe, 821 .remove = &raw3215_remove, 822 .set_online = &raw3215_set_online, 823 .set_offline = &raw3215_set_offline, 824 .int_class = IRQIO_C15, 825 }; 826 827 static void handle_write(struct raw3215_info *raw, const char *str, int count) 828 { 829 int i; 830 831 while (count > 0) { 832 i = min_t(int, count, RAW3215_BUFFER_SIZE - 1); 833 raw3215_write(raw, str, i); 834 count -= i; 835 str += i; 836 } 837 } 838 839 #ifdef CONFIG_TN3215_CONSOLE 840 /* 841 * Write a string to the 3215 console 842 */ 843 static void con3215_write(struct console *co, const char *str, unsigned int count) 844 { 845 handle_write(raw3215[0], str, count); 846 } 847 848 static struct tty_driver *con3215_device(struct console *c, int *index) 849 { 850 *index = c->index; 851 return tty3215_driver; 852 } 853 854 /* 855 * The below function is called as a panic/reboot notifier before the 856 * system enters a disabled, endless loop. 857 * 858 * Notice we must use the spin_trylock() alternative, to prevent lockups 859 * in atomic context (panic routine runs with secondary CPUs, local IRQs 860 * and preemption disabled). 861 */ 862 static int con3215_notify(struct notifier_block *self, 863 unsigned long event, void *data) 864 { 865 struct raw3215_info *raw; 866 unsigned long flags; 867 868 raw = raw3215[0]; /* console 3215 is the first one */ 869 if (!spin_trylock_irqsave(get_ccwdev_lock(raw->cdev), flags)) 870 return NOTIFY_DONE; 871 raw3215_make_room(raw, RAW3215_BUFFER_SIZE, false); 872 spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags); 873 874 return NOTIFY_DONE; 875 } 876 877 static struct notifier_block on_panic_nb = { 878 .notifier_call = con3215_notify, 879 .priority = INT_MIN + 1, /* run the callback late */ 880 }; 881 882 static struct notifier_block on_reboot_nb = { 883 .notifier_call = con3215_notify, 884 .priority = INT_MIN + 1, /* run the callback late */ 885 }; 886 887 /* 888 * The console structure for the 3215 console 889 */ 890 static struct console con3215 = { 891 .name = "ttyS", 892 .write = con3215_write, 893 .device = con3215_device, 894 .flags = CON_PRINTBUFFER, 895 }; 896 897 /* 898 * 3215 console initialization code called from console_init(). 899 */ 900 static int __init con3215_init(void) 901 { 902 struct ccw_device *cdev; 903 struct raw3215_info *raw; 904 struct raw3215_req *req; 905 int i; 906 907 /* Check if 3215 is to be the console */ 908 if (!CONSOLE_IS_3215) 909 return -ENODEV; 910 911 /* Set the console mode for VM */ 912 if (MACHINE_IS_VM) { 913 cpcmd("TERM CONMODE 3215", NULL, 0, NULL); 914 cpcmd("TERM AUTOCR OFF", NULL, 0, NULL); 915 } 916 917 /* allocate 3215 request structures */ 918 raw3215_freelist = NULL; 919 for (i = 0; i < NR_3215_REQ; i++) { 920 req = kzalloc(sizeof(struct raw3215_req), GFP_KERNEL | GFP_DMA); 921 if (!req) 922 return -ENOMEM; 923 req->next = raw3215_freelist; 924 raw3215_freelist = req; 925 } 926 927 cdev = ccw_device_create_console(&raw3215_ccw_driver); 928 if (IS_ERR(cdev)) 929 return -ENODEV; 930 931 raw3215[0] = raw = raw3215_alloc_info(); 932 raw->cdev = cdev; 933 dev_set_drvdata(&cdev->dev, raw); 934 cdev->handler = raw3215_irq; 935 936 raw->flags |= RAW3215_FIXED; 937 if (ccw_device_enable_console(cdev)) { 938 ccw_device_destroy_console(cdev); 939 raw3215_free_info(raw); 940 raw3215[0] = NULL; 941 return -ENODEV; 942 } 943 944 /* Request the console irq */ 945 if (raw3215_startup(raw) != 0) { 946 raw3215_free_info(raw); 947 raw3215[0] = NULL; 948 return -ENODEV; 949 } 950 atomic_notifier_chain_register(&panic_notifier_list, &on_panic_nb); 951 register_reboot_notifier(&on_reboot_nb); 952 register_console(&con3215); 953 return 0; 954 } 955 console_initcall(con3215_init); 956 #endif 957 958 static int tty3215_install(struct tty_driver *driver, struct tty_struct *tty) 959 { 960 struct raw3215_info *raw; 961 962 raw = raw3215[tty->index]; 963 if (raw == NULL) 964 return -ENODEV; 965 966 tty->driver_data = raw; 967 968 return tty_port_install(&raw->port, driver, tty); 969 } 970 971 /* 972 * tty3215_open 973 * 974 * This routine is called whenever a 3215 tty is opened. 975 */ 976 static int tty3215_open(struct tty_struct *tty, struct file * filp) 977 { 978 struct raw3215_info *raw = tty->driver_data; 979 980 tty_port_tty_set(&raw->port, tty); 981 982 /* 983 * Start up 3215 device 984 */ 985 return raw3215_startup(raw); 986 } 987 988 /* 989 * tty3215_close() 990 * 991 * This routine is called when the 3215 tty is closed. We wait 992 * for the remaining request to be completed. Then we clean up. 993 */ 994 static void tty3215_close(struct tty_struct *tty, struct file * filp) 995 { 996 struct raw3215_info *raw = tty->driver_data; 997 998 if (raw == NULL || tty->count > 1) 999 return; 1000 tty->closing = 1; 1001 /* Shutdown the terminal */ 1002 raw3215_shutdown(raw); 1003 tty->closing = 0; 1004 tty_port_tty_set(&raw->port, NULL); 1005 } 1006 1007 /* 1008 * Returns the amount of free space in the output buffer. 1009 */ 1010 static unsigned int tty3215_write_room(struct tty_struct *tty) 1011 { 1012 struct raw3215_info *raw = tty->driver_data; 1013 1014 /* Subtract TAB_STOP_SIZE to allow for a tab, 8 <<< 64K */ 1015 if ((RAW3215_BUFFER_SIZE - raw->count - TAB_STOP_SIZE) >= 0) 1016 return RAW3215_BUFFER_SIZE - raw->count - TAB_STOP_SIZE; 1017 else 1018 return 0; 1019 } 1020 1021 /* 1022 * String write routine for 3215 ttys 1023 */ 1024 static int tty3215_write(struct tty_struct *tty, 1025 const unsigned char *buf, int count) 1026 { 1027 handle_write(tty->driver_data, buf, count); 1028 return count; 1029 } 1030 1031 /* 1032 * Put character routine for 3215 ttys 1033 */ 1034 static int tty3215_put_char(struct tty_struct *tty, unsigned char ch) 1035 { 1036 struct raw3215_info *raw = tty->driver_data; 1037 1038 raw3215_putchar(raw, ch); 1039 1040 return 1; 1041 } 1042 1043 static void tty3215_flush_chars(struct tty_struct *tty) 1044 { 1045 } 1046 1047 /* 1048 * Returns the number of characters in the output buffer 1049 */ 1050 static unsigned int tty3215_chars_in_buffer(struct tty_struct *tty) 1051 { 1052 struct raw3215_info *raw = tty->driver_data; 1053 1054 return raw->count; 1055 } 1056 1057 static void tty3215_flush_buffer(struct tty_struct *tty) 1058 { 1059 struct raw3215_info *raw = tty->driver_data; 1060 1061 raw3215_flush_buffer(raw); 1062 tty_wakeup(tty); 1063 } 1064 1065 /* 1066 * Disable reading from a 3215 tty 1067 */ 1068 static void tty3215_throttle(struct tty_struct *tty) 1069 { 1070 struct raw3215_info *raw = tty->driver_data; 1071 1072 raw->flags |= RAW3215_THROTTLED; 1073 } 1074 1075 /* 1076 * Enable reading from a 3215 tty 1077 */ 1078 static void tty3215_unthrottle(struct tty_struct *tty) 1079 { 1080 struct raw3215_info *raw = tty->driver_data; 1081 unsigned long flags; 1082 1083 if (raw->flags & RAW3215_THROTTLED) { 1084 spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags); 1085 raw->flags &= ~RAW3215_THROTTLED; 1086 raw3215_try_io(raw); 1087 spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags); 1088 } 1089 } 1090 1091 /* 1092 * Disable writing to a 3215 tty 1093 */ 1094 static void tty3215_stop(struct tty_struct *tty) 1095 { 1096 struct raw3215_info *raw = tty->driver_data; 1097 1098 raw->flags |= RAW3215_STOPPED; 1099 } 1100 1101 /* 1102 * Enable writing to a 3215 tty 1103 */ 1104 static void tty3215_start(struct tty_struct *tty) 1105 { 1106 struct raw3215_info *raw = tty->driver_data; 1107 unsigned long flags; 1108 1109 if (raw->flags & RAW3215_STOPPED) { 1110 spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags); 1111 raw->flags &= ~RAW3215_STOPPED; 1112 raw3215_try_io(raw); 1113 spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags); 1114 } 1115 } 1116 1117 static const struct tty_operations tty3215_ops = { 1118 .install = tty3215_install, 1119 .open = tty3215_open, 1120 .close = tty3215_close, 1121 .write = tty3215_write, 1122 .put_char = tty3215_put_char, 1123 .flush_chars = tty3215_flush_chars, 1124 .write_room = tty3215_write_room, 1125 .chars_in_buffer = tty3215_chars_in_buffer, 1126 .flush_buffer = tty3215_flush_buffer, 1127 .throttle = tty3215_throttle, 1128 .unthrottle = tty3215_unthrottle, 1129 .stop = tty3215_stop, 1130 .start = tty3215_start, 1131 }; 1132 1133 static int __init con3215_setup_drop(char *str) 1134 { 1135 bool drop; 1136 int rc; 1137 1138 rc = kstrtobool(str, &drop); 1139 if (!rc) 1140 con3215_drop = drop; 1141 return rc; 1142 } 1143 early_param("con3215_drop", con3215_setup_drop); 1144 1145 /* 1146 * 3215 tty registration code called from tty_init(). 1147 * Most kernel services (incl. kmalloc) are available at this poimt. 1148 */ 1149 static int __init tty3215_init(void) 1150 { 1151 struct tty_driver *driver; 1152 int ret; 1153 1154 if (!CONSOLE_IS_3215) 1155 return 0; 1156 1157 driver = tty_alloc_driver(NR_3215, TTY_DRIVER_REAL_RAW); 1158 if (IS_ERR(driver)) 1159 return PTR_ERR(driver); 1160 1161 ret = ccw_driver_register(&raw3215_ccw_driver); 1162 if (ret) { 1163 tty_driver_kref_put(driver); 1164 return ret; 1165 } 1166 /* 1167 * Initialize the tty_driver structure 1168 * Entries in tty3215_driver that are NOT initialized: 1169 * proc_entry, set_termios, flush_buffer, set_ldisc, write_proc 1170 */ 1171 1172 driver->driver_name = "tty3215"; 1173 driver->name = "ttyS"; 1174 driver->major = TTY_MAJOR; 1175 driver->minor_start = 64; 1176 driver->type = TTY_DRIVER_TYPE_SYSTEM; 1177 driver->subtype = SYSTEM_TYPE_TTY; 1178 driver->init_termios = tty_std_termios; 1179 driver->init_termios.c_iflag = IGNBRK | IGNPAR; 1180 driver->init_termios.c_oflag = ONLCR; 1181 driver->init_termios.c_lflag = ISIG; 1182 tty_set_operations(driver, &tty3215_ops); 1183 ret = tty_register_driver(driver); 1184 if (ret) { 1185 tty_driver_kref_put(driver); 1186 return ret; 1187 } 1188 tty3215_driver = driver; 1189 return 0; 1190 } 1191 device_initcall(tty3215_init); 1192