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 <linux/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 u8 *buffer; /* pointer to output buffer */ 83 u8 *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 }; 93 94 /* array of 3215 devices structures */ 95 static struct raw3215_info *raw3215[NR_3215]; 96 /* spinlock to protect the raw3215 array */ 97 static DEFINE_SPINLOCK(raw3215_device_lock); 98 /* list of free request structures */ 99 static struct raw3215_req *raw3215_freelist; 100 /* spinlock to protect free list */ 101 static DEFINE_SPINLOCK(raw3215_freelist_lock); 102 103 static struct tty_driver *tty3215_driver; 104 static bool con3215_drop = true; 105 106 /* 107 * Get a request structure from the free list 108 */ 109 static inline struct raw3215_req *raw3215_alloc_req(void) 110 { 111 struct raw3215_req *req; 112 unsigned long flags; 113 114 spin_lock_irqsave(&raw3215_freelist_lock, flags); 115 req = raw3215_freelist; 116 raw3215_freelist = req->next; 117 spin_unlock_irqrestore(&raw3215_freelist_lock, flags); 118 return req; 119 } 120 121 /* 122 * Put a request structure back to the free list 123 */ 124 static inline void raw3215_free_req(struct raw3215_req *req) 125 { 126 unsigned long flags; 127 128 if (req->type == RAW3215_FREE) 129 return; /* don't free a free request */ 130 req->type = RAW3215_FREE; 131 spin_lock_irqsave(&raw3215_freelist_lock, flags); 132 req->next = raw3215_freelist; 133 raw3215_freelist = req; 134 spin_unlock_irqrestore(&raw3215_freelist_lock, flags); 135 } 136 137 /* 138 * Set up a read request that reads up to 160 byte from the 3215 device. 139 * If there is a queued read request it is used, but that shouldn't happen 140 * because a 3215 terminal won't accept a new read before the old one is 141 * completed. 142 */ 143 static void raw3215_mk_read_req(struct raw3215_info *raw) 144 { 145 struct raw3215_req *req; 146 struct ccw1 *ccw; 147 148 /* there can only be ONE read request at a time */ 149 req = raw->queued_read; 150 if (req == NULL) { 151 /* no queued read request, use new req structure */ 152 req = raw3215_alloc_req(); 153 req->type = RAW3215_READ; 154 req->info = raw; 155 raw->queued_read = req; 156 } 157 158 ccw = req->ccws; 159 ccw->cmd_code = 0x0A; /* read inquiry */ 160 ccw->flags = 0x20; /* ignore incorrect length */ 161 ccw->count = 160; 162 ccw->cda = virt_to_dma32(raw->inbuf); 163 } 164 165 /* 166 * Set up a write request with the information from the main structure. 167 * A ccw chain is created that writes as much as possible from the output 168 * buffer to the 3215 device. If a queued write exists it is replaced by 169 * the new, probably lengthened request. 170 */ 171 static void raw3215_mk_write_req(struct raw3215_info *raw) 172 { 173 struct raw3215_req *req; 174 struct ccw1 *ccw; 175 int len, count, ix, lines; 176 177 if (raw->count <= raw->written) 178 return; 179 /* check if there is a queued write request */ 180 req = raw->queued_write; 181 if (req == NULL) { 182 /* no queued write request, use new req structure */ 183 req = raw3215_alloc_req(); 184 req->type = RAW3215_WRITE; 185 req->info = raw; 186 raw->queued_write = req; 187 } else { 188 raw->written -= req->len; 189 } 190 191 ccw = req->ccws; 192 req->start = (raw->head - raw->count + raw->written) & 193 (RAW3215_BUFFER_SIZE - 1); 194 /* 195 * now we have to count newlines. We can at max accept 196 * RAW3215_MAX_NEWLINE newlines in a single ssch due to 197 * a restriction in VM 198 */ 199 lines = 0; 200 ix = req->start; 201 while (lines < RAW3215_MAX_NEWLINE && ix != raw->head) { 202 if (raw->buffer[ix] == 0x15) 203 lines++; 204 ix = (ix + 1) & (RAW3215_BUFFER_SIZE - 1); 205 } 206 len = ((ix - 1 - req->start) & (RAW3215_BUFFER_SIZE - 1)) + 1; 207 if (len > RAW3215_MAX_BYTES) 208 len = RAW3215_MAX_BYTES; 209 req->len = len; 210 raw->written += len; 211 212 /* set the indication if we should try to enlarge this request */ 213 req->delayable = (ix == raw->head) && (len < RAW3215_MIN_WRITE); 214 215 ix = req->start; 216 while (len > 0) { 217 if (ccw > req->ccws) 218 ccw[-1].flags |= 0x40; /* use command chaining */ 219 ccw->cmd_code = 0x01; /* write, auto carrier return */ 220 ccw->flags = 0x20; /* ignore incorrect length ind. */ 221 ccw->cda = virt_to_dma32(raw->buffer + ix); 222 count = len; 223 if (ix + count > RAW3215_BUFFER_SIZE) 224 count = RAW3215_BUFFER_SIZE - ix; 225 ccw->count = count; 226 len -= count; 227 ix = (ix + count) & (RAW3215_BUFFER_SIZE - 1); 228 ccw++; 229 } 230 /* 231 * Add a NOP to the channel program. 3215 devices are purely 232 * emulated and its much better to avoid the channel end 233 * interrupt in this case. 234 */ 235 if (ccw > req->ccws) 236 ccw[-1].flags |= 0x40; /* use command chaining */ 237 ccw->cmd_code = 0x03; /* NOP */ 238 ccw->flags = 0; 239 ccw->cda = 0; 240 ccw->count = 1; 241 } 242 243 /* 244 * Start a read or a write request 245 */ 246 static void raw3215_start_io(struct raw3215_info *raw) 247 { 248 struct raw3215_req *req; 249 int res; 250 251 req = raw->queued_read; 252 if (req != NULL && 253 !(raw->flags & (RAW3215_WORKING | RAW3215_THROTTLED))) { 254 /* dequeue request */ 255 raw->queued_read = NULL; 256 res = ccw_device_start(raw->cdev, req->ccws, 257 (unsigned long) req, 0, 0); 258 if (res != 0) { 259 /* do_IO failed, put request back to queue */ 260 raw->queued_read = req; 261 } else { 262 raw->flags |= RAW3215_WORKING; 263 } 264 } 265 req = raw->queued_write; 266 if (req != NULL && 267 !(raw->flags & (RAW3215_WORKING | RAW3215_STOPPED))) { 268 /* dequeue request */ 269 raw->queued_write = NULL; 270 res = ccw_device_start(raw->cdev, req->ccws, 271 (unsigned long) req, 0, 0); 272 if (res != 0) { 273 /* do_IO failed, put request back to queue */ 274 raw->queued_write = req; 275 } else { 276 raw->flags |= RAW3215_WORKING; 277 } 278 } 279 } 280 281 /* 282 * Function to start a delayed output after RAW3215_TIMEOUT seconds 283 */ 284 static void raw3215_timeout(struct timer_list *t) 285 { 286 struct raw3215_info *raw = from_timer(raw, t, timer); 287 unsigned long flags; 288 289 spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags); 290 raw->flags &= ~RAW3215_TIMER_RUNS; 291 raw3215_mk_write_req(raw); 292 raw3215_start_io(raw); 293 if ((raw->queued_read || raw->queued_write) && 294 !(raw->flags & RAW3215_WORKING) && 295 !(raw->flags & RAW3215_TIMER_RUNS)) { 296 raw->timer.expires = RAW3215_TIMEOUT + jiffies; 297 add_timer(&raw->timer); 298 raw->flags |= RAW3215_TIMER_RUNS; 299 } 300 spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags); 301 } 302 303 /* 304 * Function to conditionally start an IO. A read is started immediately, 305 * a write is only started immediately if the flush flag is on or the 306 * amount of data is bigger than RAW3215_MIN_WRITE. If a write is not 307 * done immediately a timer is started with a delay of RAW3215_TIMEOUT. 308 */ 309 static inline void raw3215_try_io(struct raw3215_info *raw) 310 { 311 if (!tty_port_initialized(&raw->port)) 312 return; 313 if (raw->queued_read != NULL) 314 raw3215_start_io(raw); 315 else if (raw->queued_write != NULL) { 316 if ((raw->queued_write->delayable == 0) || 317 (raw->flags & RAW3215_FLUSHING)) { 318 /* execute write requests bigger than minimum size */ 319 raw3215_start_io(raw); 320 } 321 } 322 if ((raw->queued_read || raw->queued_write) && 323 !(raw->flags & RAW3215_WORKING) && 324 !(raw->flags & RAW3215_TIMER_RUNS)) { 325 raw->timer.expires = RAW3215_TIMEOUT + jiffies; 326 add_timer(&raw->timer); 327 raw->flags |= RAW3215_TIMER_RUNS; 328 } 329 } 330 331 /* 332 * Try to start the next IO and wake up processes waiting on the tty. 333 */ 334 static void raw3215_next_io(struct raw3215_info *raw, struct tty_struct *tty) 335 { 336 raw3215_mk_write_req(raw); 337 raw3215_try_io(raw); 338 if (tty && RAW3215_BUFFER_SIZE - raw->count >= RAW3215_MIN_SPACE) 339 tty_wakeup(tty); 340 } 341 342 /* 343 * Interrupt routine, called from common io layer 344 */ 345 static void raw3215_irq(struct ccw_device *cdev, unsigned long intparm, 346 struct irb *irb) 347 { 348 struct raw3215_info *raw; 349 struct raw3215_req *req; 350 struct tty_struct *tty; 351 int cstat, dstat; 352 int count; 353 354 raw = dev_get_drvdata(&cdev->dev); 355 req = (struct raw3215_req *) intparm; 356 tty = tty_port_tty_get(&raw->port); 357 cstat = irb->scsw.cmd.cstat; 358 dstat = irb->scsw.cmd.dstat; 359 if (cstat != 0) 360 raw3215_next_io(raw, tty); 361 if (dstat & 0x01) { /* we got a unit exception */ 362 dstat &= ~0x01; /* we can ignore it */ 363 } 364 switch (dstat) { 365 case 0x80: 366 if (cstat != 0) 367 break; 368 /* Attention interrupt, someone hit the enter key */ 369 raw3215_mk_read_req(raw); 370 raw3215_next_io(raw, tty); 371 break; 372 case 0x08: 373 case 0x0C: 374 /* Channel end interrupt. */ 375 if ((raw = req->info) == NULL) 376 goto put_tty; /* That shouldn't happen ... */ 377 if (req->type == RAW3215_READ) { 378 /* store residual count, then wait for device end */ 379 req->residual = irb->scsw.cmd.count; 380 } 381 if (dstat == 0x08) 382 break; 383 fallthrough; 384 case 0x04: 385 /* Device end interrupt. */ 386 if ((raw = req->info) == NULL) 387 goto put_tty; /* That shouldn't happen ... */ 388 if (req->type == RAW3215_READ && tty != NULL) { 389 unsigned int cchar; 390 391 count = 160 - req->residual; 392 EBCASC(raw->inbuf, count); 393 cchar = ctrlchar_handle(raw->inbuf, count, tty); 394 switch (cchar & CTRLCHAR_MASK) { 395 case CTRLCHAR_SYSRQ: 396 break; 397 398 case CTRLCHAR_CTRL: 399 tty_insert_flip_char(&raw->port, cchar, 400 TTY_NORMAL); 401 tty_flip_buffer_push(&raw->port); 402 break; 403 404 case CTRLCHAR_NONE: 405 if (count < 2 || 406 (strncmp(raw->inbuf+count-2, "\252n", 2) && 407 strncmp(raw->inbuf+count-2, "^n", 2)) ) { 408 /* add the auto \n */ 409 raw->inbuf[count] = '\n'; 410 count++; 411 } else 412 count -= 2; 413 tty_insert_flip_string(&raw->port, raw->inbuf, 414 count); 415 tty_flip_buffer_push(&raw->port); 416 break; 417 } 418 } else if (req->type == RAW3215_WRITE) { 419 raw->count -= req->len; 420 raw->written -= req->len; 421 } 422 raw->flags &= ~RAW3215_WORKING; 423 raw3215_free_req(req); 424 /* check for empty wait */ 425 if (waitqueue_active(&raw->empty_wait) && 426 raw->queued_write == NULL && 427 raw->queued_read == NULL) { 428 wake_up_interruptible(&raw->empty_wait); 429 } 430 raw3215_next_io(raw, tty); 431 break; 432 default: 433 /* Strange interrupt, I'll do my best to clean up */ 434 if (req != NULL && req->type != RAW3215_FREE) { 435 if (req->type == RAW3215_WRITE) { 436 raw->count -= req->len; 437 raw->written -= req->len; 438 } 439 raw->flags &= ~RAW3215_WORKING; 440 raw3215_free_req(req); 441 } 442 raw3215_next_io(raw, tty); 443 } 444 put_tty: 445 tty_kref_put(tty); 446 } 447 448 /* 449 * Need to drop data to avoid blocking. Drop as much data as possible. 450 * This is unqueued part in the buffer and the queued part in the request. 451 * Also adjust the head position to append new data and set count 452 * accordingly. 453 * 454 * Return number of bytes available in buffer. 455 */ 456 static unsigned int raw3215_drop(struct raw3215_info *raw) 457 { 458 struct raw3215_req *req; 459 460 req = raw->queued_write; 461 if (req) { 462 /* Drop queued data and delete request */ 463 raw->written -= req->len; 464 raw3215_free_req(req); 465 raw->queued_write = NULL; 466 } 467 raw->head = (raw->head - raw->count + raw->written) & 468 (RAW3215_BUFFER_SIZE - 1); 469 raw->count = raw->written; 470 471 return RAW3215_BUFFER_SIZE - raw->count; 472 } 473 474 /* 475 * Wait until length bytes are available int the output buffer. 476 * If drop mode is active and wait condition holds true, start dropping 477 * data. 478 * Has to be called with the s390irq lock held. Can be called 479 * disabled. 480 */ 481 static unsigned int raw3215_make_room(struct raw3215_info *raw, 482 unsigned int length, bool drop) 483 { 484 while (RAW3215_BUFFER_SIZE - raw->count < length) { 485 if (drop) 486 return raw3215_drop(raw); 487 488 /* there might be a request pending */ 489 raw->flags |= RAW3215_FLUSHING; 490 raw3215_mk_write_req(raw); 491 raw3215_try_io(raw); 492 raw->flags &= ~RAW3215_FLUSHING; 493 #ifdef CONFIG_TN3215_CONSOLE 494 ccw_device_wait_idle(raw->cdev); 495 #endif 496 /* Enough room freed up ? */ 497 if (RAW3215_BUFFER_SIZE - raw->count >= length) 498 break; 499 /* there might be another cpu waiting for the lock */ 500 spin_unlock(get_ccwdev_lock(raw->cdev)); 501 udelay(100); 502 spin_lock(get_ccwdev_lock(raw->cdev)); 503 } 504 return length; 505 } 506 507 #define RAW3215_COUNT 1 508 #define RAW3215_STORE 2 509 510 /* 511 * Add text to console buffer. Find tabs in input and calculate size 512 * including tab replacement. 513 * This function operates in 2 different modes, depending on parameter 514 * opmode: 515 * RAW3215_COUNT: Get the size needed for the input string with 516 * proper tab replacement calculation. 517 * Return value is the number of bytes required to store the 518 * input. However no data is actually stored. 519 * The parameter todrop is not used. 520 * RAW3215_STORE: Add data to the console buffer. The parameter todrop is 521 * valid and contains the number of bytes to be dropped from head of 522 * string without blocking. 523 * Return value is the number of bytes copied. 524 */ 525 static unsigned int raw3215_addtext(const u8 *str, size_t length, 526 struct raw3215_info *raw, int opmode, 527 unsigned int todrop) 528 { 529 unsigned int i, blanks, expanded_size = 0; 530 unsigned int column = raw->line_pos; 531 size_t c; 532 u8 ch; 533 534 if (opmode == RAW3215_COUNT) 535 todrop = 0; 536 537 for (c = 0; c < length; ++c) { 538 blanks = 1; 539 ch = str[c]; 540 541 switch (ch) { 542 case '\n': 543 expanded_size++; 544 column = 0; 545 break; 546 case '\t': 547 blanks = TAB_STOP_SIZE - (column % TAB_STOP_SIZE); 548 column += blanks; 549 expanded_size += blanks; 550 ch = ' '; 551 break; 552 default: 553 expanded_size++; 554 column++; 555 break; 556 } 557 558 if (opmode == RAW3215_COUNT) 559 continue; 560 if (todrop && expanded_size < todrop) /* Drop head data */ 561 continue; 562 for (i = 0; i < blanks; i++) { 563 raw->buffer[raw->head] = _ascebc[ch]; 564 raw->head = (raw->head + 1) & (RAW3215_BUFFER_SIZE - 1); 565 raw->count++; 566 } 567 raw->line_pos = column; 568 } 569 return expanded_size - todrop; 570 } 571 572 /* 573 * String write routine for 3215 devices 574 */ 575 static void raw3215_write(struct raw3215_info *raw, const u8 *str, 576 size_t length) 577 { 578 unsigned int count, avail; 579 unsigned long flags; 580 581 spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags); 582 583 count = raw3215_addtext(str, length, raw, RAW3215_COUNT, 0); 584 585 avail = raw3215_make_room(raw, count, con3215_drop); 586 if (avail) { 587 raw3215_addtext(str, length, raw, RAW3215_STORE, 588 count - avail); 589 } 590 if (!(raw->flags & RAW3215_WORKING)) { 591 raw3215_mk_write_req(raw); 592 /* start or queue request */ 593 raw3215_try_io(raw); 594 } 595 spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags); 596 } 597 598 /* 599 * Put character routine for 3215 devices 600 */ 601 static void raw3215_putchar(struct raw3215_info *raw, u8 ch) 602 { 603 raw3215_write(raw, &ch, 1); 604 } 605 606 /* 607 * Flush routine, it simply sets the flush flag and tries to start 608 * pending IO. 609 */ 610 static void raw3215_flush_buffer(struct raw3215_info *raw) 611 { 612 unsigned long flags; 613 614 spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags); 615 if (raw->count > 0) { 616 raw->flags |= RAW3215_FLUSHING; 617 raw3215_try_io(raw); 618 raw->flags &= ~RAW3215_FLUSHING; 619 } 620 spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags); 621 } 622 623 /* 624 * Fire up a 3215 device. 625 */ 626 static int raw3215_startup(struct raw3215_info *raw) 627 { 628 unsigned long flags; 629 630 if (tty_port_initialized(&raw->port)) 631 return 0; 632 raw->line_pos = 0; 633 tty_port_set_initialized(&raw->port, true); 634 spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags); 635 raw3215_try_io(raw); 636 spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags); 637 638 return 0; 639 } 640 641 /* 642 * Shutdown a 3215 device. 643 */ 644 static void raw3215_shutdown(struct raw3215_info *raw) 645 { 646 DECLARE_WAITQUEUE(wait, current); 647 unsigned long flags; 648 649 if (!tty_port_initialized(&raw->port) || (raw->flags & RAW3215_FIXED)) 650 return; 651 /* Wait for outstanding requests, then free irq */ 652 spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags); 653 if ((raw->flags & RAW3215_WORKING) || 654 raw->queued_write != NULL || 655 raw->queued_read != NULL) { 656 add_wait_queue(&raw->empty_wait, &wait); 657 set_current_state(TASK_INTERRUPTIBLE); 658 spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags); 659 schedule(); 660 spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags); 661 remove_wait_queue(&raw->empty_wait, &wait); 662 set_current_state(TASK_RUNNING); 663 tty_port_set_initialized(&raw->port, true); 664 } 665 spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags); 666 } 667 668 static struct raw3215_info *raw3215_alloc_info(void) 669 { 670 struct raw3215_info *info; 671 672 info = kzalloc(sizeof(struct raw3215_info), GFP_KERNEL | GFP_DMA); 673 if (!info) 674 return NULL; 675 676 info->buffer = kzalloc(RAW3215_BUFFER_SIZE, GFP_KERNEL | GFP_DMA); 677 info->inbuf = kzalloc(RAW3215_INBUF_SIZE, GFP_KERNEL | GFP_DMA); 678 if (!info->buffer || !info->inbuf) { 679 kfree(info->inbuf); 680 kfree(info->buffer); 681 kfree(info); 682 return NULL; 683 } 684 685 timer_setup(&info->timer, raw3215_timeout, 0); 686 init_waitqueue_head(&info->empty_wait); 687 tty_port_init(&info->port); 688 689 return info; 690 } 691 692 static void raw3215_free_info(struct raw3215_info *raw) 693 { 694 kfree(raw->inbuf); 695 kfree(raw->buffer); 696 tty_port_destroy(&raw->port); 697 kfree(raw); 698 } 699 700 static int raw3215_probe(struct ccw_device *cdev) 701 { 702 struct raw3215_info *raw; 703 int line; 704 705 /* Console is special. */ 706 if (raw3215[0] && (raw3215[0] == dev_get_drvdata(&cdev->dev))) 707 return 0; 708 709 raw = raw3215_alloc_info(); 710 if (raw == NULL) 711 return -ENOMEM; 712 713 raw->cdev = cdev; 714 dev_set_drvdata(&cdev->dev, raw); 715 cdev->handler = raw3215_irq; 716 717 spin_lock(&raw3215_device_lock); 718 for (line = 0; line < NR_3215; line++) { 719 if (!raw3215[line]) { 720 raw3215[line] = raw; 721 break; 722 } 723 } 724 spin_unlock(&raw3215_device_lock); 725 if (line == NR_3215) { 726 raw3215_free_info(raw); 727 return -ENODEV; 728 } 729 730 return 0; 731 } 732 733 static void raw3215_remove(struct ccw_device *cdev) 734 { 735 struct raw3215_info *raw; 736 unsigned int line; 737 738 ccw_device_set_offline(cdev); 739 raw = dev_get_drvdata(&cdev->dev); 740 if (raw) { 741 spin_lock(&raw3215_device_lock); 742 for (line = 0; line < NR_3215; line++) 743 if (raw3215[line] == raw) 744 break; 745 raw3215[line] = NULL; 746 spin_unlock(&raw3215_device_lock); 747 dev_set_drvdata(&cdev->dev, NULL); 748 raw3215_free_info(raw); 749 } 750 } 751 752 static int raw3215_set_online(struct ccw_device *cdev) 753 { 754 struct raw3215_info *raw; 755 756 raw = dev_get_drvdata(&cdev->dev); 757 if (!raw) 758 return -ENODEV; 759 760 return raw3215_startup(raw); 761 } 762 763 static int raw3215_set_offline(struct ccw_device *cdev) 764 { 765 struct raw3215_info *raw; 766 767 raw = dev_get_drvdata(&cdev->dev); 768 if (!raw) 769 return -ENODEV; 770 771 raw3215_shutdown(raw); 772 773 return 0; 774 } 775 776 static struct ccw_device_id raw3215_id[] = { 777 { CCW_DEVICE(0x3215, 0) }, 778 { /* end of list */ }, 779 }; 780 781 static ssize_t con_drop_store(struct device_driver *dev, const char *buf, size_t count) 782 { 783 bool drop; 784 int rc; 785 786 rc = kstrtobool(buf, &drop); 787 if (!rc) 788 con3215_drop = drop; 789 return rc ?: count; 790 } 791 792 static ssize_t con_drop_show(struct device_driver *dev, char *buf) 793 { 794 return sysfs_emit(buf, "%d\n", con3215_drop ? 1 : 0); 795 } 796 797 static DRIVER_ATTR_RW(con_drop); 798 799 static struct attribute *con3215_drv_attrs[] = { 800 &driver_attr_con_drop.attr, 801 NULL, 802 }; 803 804 static struct attribute_group con3215_drv_attr_group = { 805 .attrs = con3215_drv_attrs, 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 u8 *str, size_t count) 828 { 829 while (count > 0) { 830 size_t i = min_t(size_t, count, RAW3215_BUFFER_SIZE - 1); 831 raw3215_write(raw, str, i); 832 count -= i; 833 str += i; 834 } 835 } 836 837 #ifdef CONFIG_TN3215_CONSOLE 838 /* 839 * Write a string to the 3215 console 840 */ 841 static void con3215_write(struct console *co, const char *str, unsigned int count) 842 { 843 handle_write(raw3215[0], str, count); 844 } 845 846 static struct tty_driver *con3215_device(struct console *c, int *index) 847 { 848 *index = c->index; 849 return tty3215_driver; 850 } 851 852 /* 853 * The below function is called as a panic/reboot notifier before the 854 * system enters a disabled, endless loop. 855 * 856 * Notice we must use the spin_trylock() alternative, to prevent lockups 857 * in atomic context (panic routine runs with secondary CPUs, local IRQs 858 * and preemption disabled). 859 */ 860 static int con3215_notify(struct notifier_block *self, 861 unsigned long event, void *data) 862 { 863 struct raw3215_info *raw; 864 unsigned long flags; 865 866 raw = raw3215[0]; /* console 3215 is the first one */ 867 if (!spin_trylock_irqsave(get_ccwdev_lock(raw->cdev), flags)) 868 return NOTIFY_DONE; 869 raw3215_make_room(raw, RAW3215_BUFFER_SIZE, false); 870 spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags); 871 872 return NOTIFY_DONE; 873 } 874 875 static struct notifier_block on_panic_nb = { 876 .notifier_call = con3215_notify, 877 .priority = INT_MIN + 1, /* run the callback late */ 878 }; 879 880 static struct notifier_block on_reboot_nb = { 881 .notifier_call = con3215_notify, 882 .priority = INT_MIN + 1, /* run the callback late */ 883 }; 884 885 /* 886 * The console structure for the 3215 console 887 */ 888 static struct console con3215 = { 889 .name = "ttyS", 890 .write = con3215_write, 891 .device = con3215_device, 892 .flags = CON_PRINTBUFFER, 893 }; 894 895 /* 896 * 3215 console initialization code called from console_init(). 897 */ 898 static int __init con3215_init(void) 899 { 900 struct ccw_device *cdev; 901 struct raw3215_info *raw; 902 struct raw3215_req *req; 903 int i; 904 905 /* Check if 3215 is to be the console */ 906 if (!CONSOLE_IS_3215) 907 return -ENODEV; 908 909 /* Set the console mode for VM */ 910 if (MACHINE_IS_VM) { 911 cpcmd("TERM CONMODE 3215", NULL, 0, NULL); 912 cpcmd("TERM AUTOCR OFF", NULL, 0, NULL); 913 } 914 915 /* allocate 3215 request structures */ 916 raw3215_freelist = NULL; 917 for (i = 0; i < NR_3215_REQ; i++) { 918 req = kzalloc(sizeof(struct raw3215_req), GFP_KERNEL | GFP_DMA); 919 if (!req) 920 return -ENOMEM; 921 req->next = raw3215_freelist; 922 raw3215_freelist = req; 923 } 924 925 cdev = ccw_device_create_console(&raw3215_ccw_driver); 926 if (IS_ERR(cdev)) 927 return -ENODEV; 928 929 raw3215[0] = raw = raw3215_alloc_info(); 930 raw->cdev = cdev; 931 dev_set_drvdata(&cdev->dev, raw); 932 cdev->handler = raw3215_irq; 933 934 raw->flags |= RAW3215_FIXED; 935 if (ccw_device_enable_console(cdev)) { 936 ccw_device_destroy_console(cdev); 937 raw3215_free_info(raw); 938 raw3215[0] = NULL; 939 return -ENODEV; 940 } 941 942 /* Request the console irq */ 943 if (raw3215_startup(raw) != 0) { 944 raw3215_free_info(raw); 945 raw3215[0] = NULL; 946 return -ENODEV; 947 } 948 atomic_notifier_chain_register(&panic_notifier_list, &on_panic_nb); 949 register_reboot_notifier(&on_reboot_nb); 950 register_console(&con3215); 951 return 0; 952 } 953 console_initcall(con3215_init); 954 #endif 955 956 static int tty3215_install(struct tty_driver *driver, struct tty_struct *tty) 957 { 958 struct raw3215_info *raw; 959 960 raw = raw3215[tty->index]; 961 if (raw == NULL) 962 return -ENODEV; 963 964 tty->driver_data = raw; 965 966 return tty_port_install(&raw->port, driver, tty); 967 } 968 969 /* 970 * tty3215_open 971 * 972 * This routine is called whenever a 3215 tty is opened. 973 */ 974 static int tty3215_open(struct tty_struct *tty, struct file * filp) 975 { 976 struct raw3215_info *raw = tty->driver_data; 977 978 tty_port_tty_set(&raw->port, tty); 979 980 /* 981 * Start up 3215 device 982 */ 983 return raw3215_startup(raw); 984 } 985 986 /* 987 * tty3215_close() 988 * 989 * This routine is called when the 3215 tty is closed. We wait 990 * for the remaining request to be completed. Then we clean up. 991 */ 992 static void tty3215_close(struct tty_struct *tty, struct file * filp) 993 { 994 struct raw3215_info *raw = tty->driver_data; 995 996 if (raw == NULL || tty->count > 1) 997 return; 998 tty->closing = 1; 999 /* Shutdown the terminal */ 1000 raw3215_shutdown(raw); 1001 tty->closing = 0; 1002 tty_port_tty_set(&raw->port, NULL); 1003 } 1004 1005 /* 1006 * Returns the amount of free space in the output buffer. 1007 */ 1008 static unsigned int tty3215_write_room(struct tty_struct *tty) 1009 { 1010 struct raw3215_info *raw = tty->driver_data; 1011 1012 /* Subtract TAB_STOP_SIZE to allow for a tab, 8 <<< 64K */ 1013 if ((RAW3215_BUFFER_SIZE - raw->count - TAB_STOP_SIZE) >= 0) 1014 return RAW3215_BUFFER_SIZE - raw->count - TAB_STOP_SIZE; 1015 else 1016 return 0; 1017 } 1018 1019 /* 1020 * String write routine for 3215 ttys 1021 */ 1022 static ssize_t tty3215_write(struct tty_struct *tty, const u8 *buf, 1023 size_t count) 1024 { 1025 handle_write(tty->driver_data, buf, count); 1026 return count; 1027 } 1028 1029 /* 1030 * Put character routine for 3215 ttys 1031 */ 1032 static int tty3215_put_char(struct tty_struct *tty, u8 ch) 1033 { 1034 struct raw3215_info *raw = tty->driver_data; 1035 1036 raw3215_putchar(raw, ch); 1037 1038 return 1; 1039 } 1040 1041 static void tty3215_flush_chars(struct tty_struct *tty) 1042 { 1043 } 1044 1045 /* 1046 * Returns the number of characters in the output buffer 1047 */ 1048 static unsigned int tty3215_chars_in_buffer(struct tty_struct *tty) 1049 { 1050 struct raw3215_info *raw = tty->driver_data; 1051 1052 return raw->count; 1053 } 1054 1055 static void tty3215_flush_buffer(struct tty_struct *tty) 1056 { 1057 struct raw3215_info *raw = tty->driver_data; 1058 1059 raw3215_flush_buffer(raw); 1060 tty_wakeup(tty); 1061 } 1062 1063 /* 1064 * Disable reading from a 3215 tty 1065 */ 1066 static void tty3215_throttle(struct tty_struct *tty) 1067 { 1068 struct raw3215_info *raw = tty->driver_data; 1069 1070 raw->flags |= RAW3215_THROTTLED; 1071 } 1072 1073 /* 1074 * Enable reading from a 3215 tty 1075 */ 1076 static void tty3215_unthrottle(struct tty_struct *tty) 1077 { 1078 struct raw3215_info *raw = tty->driver_data; 1079 unsigned long flags; 1080 1081 if (raw->flags & RAW3215_THROTTLED) { 1082 spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags); 1083 raw->flags &= ~RAW3215_THROTTLED; 1084 raw3215_try_io(raw); 1085 spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags); 1086 } 1087 } 1088 1089 /* 1090 * Disable writing to a 3215 tty 1091 */ 1092 static void tty3215_stop(struct tty_struct *tty) 1093 { 1094 struct raw3215_info *raw = tty->driver_data; 1095 1096 raw->flags |= RAW3215_STOPPED; 1097 } 1098 1099 /* 1100 * Enable writing to a 3215 tty 1101 */ 1102 static void tty3215_start(struct tty_struct *tty) 1103 { 1104 struct raw3215_info *raw = tty->driver_data; 1105 unsigned long flags; 1106 1107 if (raw->flags & RAW3215_STOPPED) { 1108 spin_lock_irqsave(get_ccwdev_lock(raw->cdev), flags); 1109 raw->flags &= ~RAW3215_STOPPED; 1110 raw3215_try_io(raw); 1111 spin_unlock_irqrestore(get_ccwdev_lock(raw->cdev), flags); 1112 } 1113 } 1114 1115 static const struct tty_operations tty3215_ops = { 1116 .install = tty3215_install, 1117 .open = tty3215_open, 1118 .close = tty3215_close, 1119 .write = tty3215_write, 1120 .put_char = tty3215_put_char, 1121 .flush_chars = tty3215_flush_chars, 1122 .write_room = tty3215_write_room, 1123 .chars_in_buffer = tty3215_chars_in_buffer, 1124 .flush_buffer = tty3215_flush_buffer, 1125 .throttle = tty3215_throttle, 1126 .unthrottle = tty3215_unthrottle, 1127 .stop = tty3215_stop, 1128 .start = tty3215_start, 1129 }; 1130 1131 static int __init con3215_setup_drop(char *str) 1132 { 1133 bool drop; 1134 int rc; 1135 1136 rc = kstrtobool(str, &drop); 1137 if (!rc) 1138 con3215_drop = drop; 1139 return rc; 1140 } 1141 early_param("con3215_drop", con3215_setup_drop); 1142 1143 /* 1144 * 3215 tty registration code called from tty_init(). 1145 * Most kernel services (incl. kmalloc) are available at this poimt. 1146 */ 1147 static int __init tty3215_init(void) 1148 { 1149 struct tty_driver *driver; 1150 int ret; 1151 1152 if (!CONSOLE_IS_3215) 1153 return 0; 1154 1155 driver = tty_alloc_driver(NR_3215, TTY_DRIVER_REAL_RAW); 1156 if (IS_ERR(driver)) 1157 return PTR_ERR(driver); 1158 1159 ret = ccw_driver_register(&raw3215_ccw_driver); 1160 if (ret) { 1161 tty_driver_kref_put(driver); 1162 return ret; 1163 } 1164 /* 1165 * Initialize the tty_driver structure 1166 * Entries in tty3215_driver that are NOT initialized: 1167 * proc_entry, set_termios, flush_buffer, set_ldisc, write_proc 1168 */ 1169 1170 driver->driver_name = "tty3215"; 1171 driver->name = "ttyS"; 1172 driver->major = TTY_MAJOR; 1173 driver->minor_start = 64; 1174 driver->type = TTY_DRIVER_TYPE_SYSTEM; 1175 driver->subtype = SYSTEM_TYPE_TTY; 1176 driver->init_termios = tty_std_termios; 1177 driver->init_termios.c_iflag = IGNBRK | IGNPAR; 1178 driver->init_termios.c_oflag = ONLCR; 1179 driver->init_termios.c_lflag = ISIG; 1180 tty_set_operations(driver, &tty3215_ops); 1181 ret = tty_register_driver(driver); 1182 if (ret) { 1183 tty_driver_kref_put(driver); 1184 return ret; 1185 } 1186 tty3215_driver = driver; 1187 return 0; 1188 } 1189 device_initcall(tty3215_init); 1190