1/* 2 * generic_serial.c 3 * 4 * Copyright (C) 1998/1999 R.E.Wolff@BitWizard.nl 5 * 6 * written for the SX serial driver. 7 * Contains the code that should be shared over all the serial drivers. 8 * 9 * Credit for the idea to do it this way might go to Alan Cox. 10 * 11 * 12 * Version 0.1 -- December, 1998. Initial version. 13 * Version 0.2 -- March, 1999. Some more routines. Bugfixes. Etc. 14 * Version 0.5 -- August, 1999. Some more fixes. Reformat for Linus. 15 * 16 * BitWizard is actively maintaining this file. We sometimes find 17 * that someone submitted changes to this file. We really appreciate 18 * your help, but please submit changes through us. We're doing our 19 * best to be responsive. -- REW 20 * */ 21 22#include <linux/module.h> 23#include <linux/kernel.h> 24#include <linux/tty.h> 25#include <linux/serial.h> 26#include <linux/mm.h> 27#include <linux/generic_serial.h> 28#include <linux/interrupt.h> 29#include <linux/tty_flip.h> 30#include <linux/delay.h> 31#include <asm/semaphore.h> 32#include <asm/uaccess.h> 33 34#define DEBUG 35 36static int gs_debug; 37 38#ifdef DEBUG 39#define gs_dprintk(f, str...) if (gs_debug & f) printk (str) 40#else 41#define gs_dprintk(f, str...) /* nothing */ 42#endif 43 44#define func_enter() gs_dprintk (GS_DEBUG_FLOW, "gs: enter %s\n", __FUNCTION__) 45#define func_exit() gs_dprintk (GS_DEBUG_FLOW, "gs: exit %s\n", __FUNCTION__) 46#define NEW_WRITE_LOCKING 1 47#if NEW_WRITE_LOCKING 48#define DECL /* Nothing */ 49#define LOCKIT mutex_lock(& port->port_write_mutex); 50#define RELEASEIT mutex_unlock(&port->port_write_mutex); 51#else 52#define DECL unsigned long flags; 53#define LOCKIT save_flags (flags);cli () 54#define RELEASEIT restore_flags (flags) 55#endif 56 57#define RS_EVENT_WRITE_WAKEUP 1 58 59module_param(gs_debug, int, 0644); 60 61 62void gs_put_char(struct tty_struct * tty, unsigned char ch) 63{ 64 struct gs_port *port; 65 DECL 66 67 func_enter (); 68 69 if (!tty) return; 70 71 port = tty->driver_data; 72 73 if (!port) return; 74 75 if (! (port->flags & ASYNC_INITIALIZED)) return; 76 77 /* Take a lock on the serial tranmit buffer! */ 78 LOCKIT; 79 80 if (port->xmit_cnt >= SERIAL_XMIT_SIZE - 1) { 81 /* Sorry, buffer is full, drop character. Update statistics???? -- REW */ 82 RELEASEIT; 83 return; 84 } 85 86 port->xmit_buf[port->xmit_head++] = ch; 87 port->xmit_head &= SERIAL_XMIT_SIZE - 1; 88 port->xmit_cnt++; /* Characters in buffer */ 89 90 RELEASEIT; 91 func_exit (); 92} 93 94 95#ifdef NEW_WRITE_LOCKING 96 97/* 98> Problems to take into account are: 99> -1- Interrupts that empty part of the buffer. 100> -2- page faults on the access to userspace. 101> -3- Other processes that are also trying to do a "write". 102*/ 103 104int gs_write(struct tty_struct * tty, 105 const unsigned char *buf, int count) 106{ 107 struct gs_port *port; 108 int c, total = 0; 109 int t; 110 111 func_enter (); 112 113 if (!tty) return 0; 114 115 port = tty->driver_data; 116 117 if (!port) return 0; 118 119 if (! (port->flags & ASYNC_INITIALIZED)) 120 return 0; 121 122 /* get exclusive "write" access to this port (problem 3) */ 123 /* This is not a spinlock because we can have a disk access (page 124 fault) in copy_from_user */ 125 mutex_lock(& port->port_write_mutex); 126 127 while (1) { 128 129 c = count; 130 131 /* This is safe because we "OWN" the "head". Noone else can 132 change the "head": we own the port_write_mutex. */ 133 /* Don't overrun the end of the buffer */ 134 t = SERIAL_XMIT_SIZE - port->xmit_head; 135 if (t < c) c = t; 136 137 /* This is safe because the xmit_cnt can only decrease. This 138 would increase "t", so we might copy too little chars. */ 139 /* Don't copy past the "head" of the buffer */ 140 t = SERIAL_XMIT_SIZE - 1 - port->xmit_cnt; 141 if (t < c) c = t; 142 143 /* Can't copy more? break out! */ 144 if (c <= 0) break; 145 146 memcpy (port->xmit_buf + port->xmit_head, buf, c); 147 148 port -> xmit_cnt += c; 149 port -> xmit_head = (port->xmit_head + c) & (SERIAL_XMIT_SIZE -1); 150 buf += c; 151 count -= c; 152 total += c; 153 } 154 mutex_unlock(& port->port_write_mutex); 155 156 gs_dprintk (GS_DEBUG_WRITE, "write: interrupts are %s\n", 157 (port->flags & GS_TX_INTEN)?"enabled": "disabled"); 158 159 if (port->xmit_cnt && 160 !tty->stopped && 161 !tty->hw_stopped && 162 !(port->flags & GS_TX_INTEN)) { 163 port->flags |= GS_TX_INTEN; 164 port->rd->enable_tx_interrupts (port); 165 } 166 func_exit (); 167 return total; 168} 169#else 170/* 171> Problems to take into account are: 172> -1- Interrupts that empty part of the buffer. 173> -2- page faults on the access to userspace. 174> -3- Other processes that are also trying to do a "write". 175*/ 176 177int gs_write(struct tty_struct * tty, 178 const unsigned char *buf, int count) 179{ 180 struct gs_port *port; 181 int c, total = 0; 182 int t; 183 unsigned long flags; 184 185 func_enter (); 186 187 /* The standard serial driver returns 0 in this case. 188 That sounds to me as "No error, I just didn't get to writing any 189 bytes. Feel free to try again." 190 The "official" way to write n bytes from buf is: 191 192 for (nwritten = 0;nwritten < n;nwritten += rv) { 193 rv = write (fd, buf+nwritten, n-nwritten); 194 if (rv < 0) break; // Error: bail out. // 195 } 196 197 which will loop endlessly in this case. The manual page for write 198 agrees with me. In practise almost everybody writes 199 "write (fd, buf,n);" but some people might have had to deal with 200 incomplete writes in the past and correctly implemented it by now... 201 */ 202 203 if (!tty) return -EIO; 204 205 port = tty->driver_data; 206 if (!port || !port->xmit_buf) 207 return -EIO; 208 209 local_save_flags(flags); 210 while (1) { 211 cli(); 212 c = count; 213 214 /* This is safe because we "OWN" the "head". Noone else can 215 change the "head": we own the port_write_mutex. */ 216 /* Don't overrun the end of the buffer */ 217 t = SERIAL_XMIT_SIZE - port->xmit_head; 218 if (t < c) c = t; 219 220 /* This is safe because the xmit_cnt can only decrease. This 221 would increase "t", so we might copy too little chars. */ 222 /* Don't copy past the "head" of the buffer */ 223 t = SERIAL_XMIT_SIZE - 1 - port->xmit_cnt; 224 if (t < c) c = t; 225 226 /* Can't copy more? break out! */ 227 if (c <= 0) { 228 local_restore_flags(flags); 229 break; 230 } 231 memcpy(port->xmit_buf + port->xmit_head, buf, c); 232 port->xmit_head = ((port->xmit_head + c) & 233 (SERIAL_XMIT_SIZE-1)); 234 port->xmit_cnt += c; 235 local_restore_flags(flags); 236 buf += c; 237 count -= c; 238 total += c; 239 } 240 241 if (port->xmit_cnt && 242 !tty->stopped && 243 !tty->hw_stopped && 244 !(port->flags & GS_TX_INTEN)) { 245 port->flags |= GS_TX_INTEN; 246 port->rd->enable_tx_interrupts (port); 247 } 248 func_exit (); 249 return total; 250} 251 252#endif 253 254 255 256int gs_write_room(struct tty_struct * tty) 257{ 258 struct gs_port *port = tty->driver_data; 259 int ret; 260 261 func_enter (); 262 ret = SERIAL_XMIT_SIZE - port->xmit_cnt - 1; 263 if (ret < 0) 264 ret = 0; 265 func_exit (); 266 return ret; 267} 268 269 270int gs_chars_in_buffer(struct tty_struct *tty) 271{ 272 struct gs_port *port = tty->driver_data; 273 func_enter (); 274 275 func_exit (); 276 return port->xmit_cnt; 277} 278 279 280static int gs_real_chars_in_buffer(struct tty_struct *tty) 281{ 282 struct gs_port *port; 283 func_enter (); 284 285 if (!tty) return 0; 286 port = tty->driver_data; 287 288 if (!port->rd) return 0; 289 if (!port->rd->chars_in_buffer) return 0; 290 291 func_exit (); 292 return port->xmit_cnt + port->rd->chars_in_buffer (port); 293} 294 295 296static int gs_wait_tx_flushed (void * ptr, unsigned long timeout) 297{ 298 struct gs_port *port = ptr; 299 unsigned long end_jiffies; 300 int jiffies_to_transmit, charsleft = 0, rv = 0; 301 int rcib; 302 303 func_enter(); 304 305 gs_dprintk (GS_DEBUG_FLUSH, "port=%p.\n", port); 306 if (port) { 307 gs_dprintk (GS_DEBUG_FLUSH, "xmit_cnt=%x, xmit_buf=%p, tty=%p.\n", 308 port->xmit_cnt, port->xmit_buf, port->tty); 309 } 310 311 if (!port || port->xmit_cnt < 0 || !port->xmit_buf) { 312 gs_dprintk (GS_DEBUG_FLUSH, "ERROR: !port, !port->xmit_buf or prot->xmit_cnt < 0.\n"); 313 func_exit(); 314 return -EINVAL; /* This is an error which we don't know how to handle. */ 315 } 316 317 rcib = gs_real_chars_in_buffer(port->tty); 318 319 if(rcib <= 0) { 320 gs_dprintk (GS_DEBUG_FLUSH, "nothing to wait for.\n"); 321 func_exit(); 322 return rv; 323 } 324 /* stop trying: now + twice the time it would normally take + seconds */ 325 if (timeout == 0) timeout = MAX_SCHEDULE_TIMEOUT; 326 end_jiffies = jiffies; 327 if (timeout != MAX_SCHEDULE_TIMEOUT) 328 end_jiffies += port->baud?(2 * rcib * 10 * HZ / port->baud):0; 329 end_jiffies += timeout; 330 331 gs_dprintk (GS_DEBUG_FLUSH, "now=%lx, end=%lx (%ld).\n", 332 jiffies, end_jiffies, end_jiffies-jiffies); 333 334 while ((charsleft = gs_real_chars_in_buffer (port->tty)) && 335 time_after (end_jiffies, jiffies)) { 336 /* Units check: 337 chars * (bits/char) * (jiffies /sec) / (bits/sec) = jiffies! 338 check! */ 339 340 charsleft += 16; /* Allow 16 chars more to be transmitted ... */ 341 jiffies_to_transmit = port->baud?(1 + charsleft * 10 * HZ / port->baud):0; 342 /* ^^^ Round up.... */ 343 if (jiffies_to_transmit <= 0) jiffies_to_transmit = 1; 344 345 gs_dprintk (GS_DEBUG_FLUSH, "Expect to finish in %d jiffies " 346 "(%d chars).\n", jiffies_to_transmit, charsleft); 347 348 msleep_interruptible(jiffies_to_msecs(jiffies_to_transmit)); 349 if (signal_pending (current)) { 350 gs_dprintk (GS_DEBUG_FLUSH, "Signal pending. Bombing out: "); 351 rv = -EINTR; 352 break; 353 } 354 } 355 356 gs_dprintk (GS_DEBUG_FLUSH, "charsleft = %d.\n", charsleft); 357 set_current_state (TASK_RUNNING); 358 359 func_exit(); 360 return rv; 361} 362 363 364 365void gs_flush_buffer(struct tty_struct *tty) 366{ 367 struct gs_port *port; 368 unsigned long flags; 369 370 func_enter (); 371 372 if (!tty) return; 373 374 port = tty->driver_data; 375 376 if (!port) return; 377 378 spin_lock_irqsave (&port->driver_lock, flags); 379 port->xmit_cnt = port->xmit_head = port->xmit_tail = 0; 380 spin_unlock_irqrestore (&port->driver_lock, flags); 381 382 tty_wakeup(tty); 383 func_exit (); 384} 385 386 387void gs_flush_chars(struct tty_struct * tty) 388{ 389 struct gs_port *port; 390 391 func_enter (); 392 393 if (!tty) return; 394 395 port = tty->driver_data; 396 397 if (!port) return; 398 399 if (port->xmit_cnt <= 0 || tty->stopped || tty->hw_stopped || 400 !port->xmit_buf) { 401 func_exit (); 402 return; 403 } 404 405 /* Beats me -- REW */ 406 port->flags |= GS_TX_INTEN; 407 port->rd->enable_tx_interrupts (port); 408 func_exit (); 409} 410 411 412void gs_stop(struct tty_struct * tty) 413{ 414 struct gs_port *port; 415 416 func_enter (); 417 418 if (!tty) return; 419 420 port = tty->driver_data; 421 422 if (!port) return; 423 424 if (port->xmit_cnt && 425 port->xmit_buf && 426 (port->flags & GS_TX_INTEN) ) { 427 port->flags &= ~GS_TX_INTEN; 428 port->rd->disable_tx_interrupts (port); 429 } 430 func_exit (); 431} 432 433 434void gs_start(struct tty_struct * tty) 435{ 436 struct gs_port *port; 437 438 if (!tty) return; 439 440 port = tty->driver_data; 441 442 if (!port) return; 443 444 if (port->xmit_cnt && 445 port->xmit_buf && 446 !(port->flags & GS_TX_INTEN) ) { 447 port->flags |= GS_TX_INTEN; 448 port->rd->enable_tx_interrupts (port); 449 } 450 func_exit (); 451} 452 453 454static void gs_shutdown_port (struct gs_port *port) 455{ 456 unsigned long flags; 457 458 func_enter(); 459 460 if (!port) return; 461 462 if (!(port->flags & ASYNC_INITIALIZED)) 463 return; 464 465 spin_lock_irqsave(&port->driver_lock, flags); 466 467 if (port->xmit_buf) { 468 free_page((unsigned long) port->xmit_buf); 469 port->xmit_buf = NULL; 470 } 471 472 if (port->tty) 473 set_bit(TTY_IO_ERROR, &port->tty->flags); 474 475 port->rd->shutdown_port (port); 476 477 port->flags &= ~ASYNC_INITIALIZED; 478 spin_unlock_irqrestore(&port->driver_lock, flags); 479 480 func_exit(); 481} 482 483 484void gs_hangup(struct tty_struct *tty) 485{ 486 struct gs_port *port; 487 488 func_enter (); 489 490 if (!tty) return; 491 492 port = tty->driver_data; 493 tty = port->tty; 494 if (!tty) 495 return; 496 497 gs_shutdown_port (port); 498 port->flags &= ~(ASYNC_NORMAL_ACTIVE|GS_ACTIVE); 499 port->tty = NULL; 500 port->count = 0; 501 502 wake_up_interruptible(&port->open_wait); 503 func_exit (); 504} 505 506 507int gs_block_til_ready(void *port_, struct file * filp) 508{ 509 struct gs_port *port = port_; 510 DECLARE_WAITQUEUE(wait, current); 511 int retval; 512 int do_clocal = 0; 513 int CD; 514 struct tty_struct *tty; 515 unsigned long flags; 516 517 func_enter (); 518 519 if (!port) return 0; 520 521 tty = port->tty; 522 523 if (!tty) return 0; 524 525 gs_dprintk (GS_DEBUG_BTR, "Entering gs_block_till_ready.\n"); 526 /* 527 * If the device is in the middle of being closed, then block 528 * until it's done, and then try again. 529 */ 530 if (tty_hung_up_p(filp) || port->flags & ASYNC_CLOSING) { 531 interruptible_sleep_on(&port->close_wait); 532 if (port->flags & ASYNC_HUP_NOTIFY) 533 return -EAGAIN; 534 else 535 return -ERESTARTSYS; 536 } 537 538 gs_dprintk (GS_DEBUG_BTR, "after hung up\n"); 539 540 /* 541 * If non-blocking mode is set, or the port is not enabled, 542 * then make the check up front and then exit. 543 */ 544 if ((filp->f_flags & O_NONBLOCK) || 545 (tty->flags & (1 << TTY_IO_ERROR))) { 546 port->flags |= ASYNC_NORMAL_ACTIVE; 547 return 0; 548 } 549 550 gs_dprintk (GS_DEBUG_BTR, "after nonblock\n"); 551 552 if (C_CLOCAL(tty)) 553 do_clocal = 1; 554 555 /* 556 * Block waiting for the carrier detect and the line to become 557 * free (i.e., not in use by the callout). While we are in 558 * this loop, port->count is dropped by one, so that 559 * rs_close() knows when to free things. We restore it upon 560 * exit, either normal or abnormal. 561 */ 562 retval = 0; 563 564 add_wait_queue(&port->open_wait, &wait); 565 566 gs_dprintk (GS_DEBUG_BTR, "after add waitq.\n"); 567 spin_lock_irqsave(&port->driver_lock, flags); 568 if (!tty_hung_up_p(filp)) { 569 port->count--; 570 } 571 spin_unlock_irqrestore(&port->driver_lock, flags); 572 port->blocked_open++; 573 while (1) { 574 CD = port->rd->get_CD (port); 575 gs_dprintk (GS_DEBUG_BTR, "CD is now %d.\n", CD); 576 set_current_state (TASK_INTERRUPTIBLE); 577 if (tty_hung_up_p(filp) || 578 !(port->flags & ASYNC_INITIALIZED)) { 579 if (port->flags & ASYNC_HUP_NOTIFY) 580 retval = -EAGAIN; 581 else 582 retval = -ERESTARTSYS; 583 break; 584 } 585 if (!(port->flags & ASYNC_CLOSING) && 586 (do_clocal || CD)) 587 break; 588 gs_dprintk (GS_DEBUG_BTR, "signal_pending is now: %d (%lx)\n", 589 (int)signal_pending (current), *(long*)(¤t->blocked)); 590 if (signal_pending(current)) { 591 retval = -ERESTARTSYS; 592 break; 593 } 594 schedule(); 595 } 596 gs_dprintk (GS_DEBUG_BTR, "Got out of the loop. (%d)\n", 597 port->blocked_open); 598 set_current_state (TASK_RUNNING); 599 remove_wait_queue(&port->open_wait, &wait); 600 if (!tty_hung_up_p(filp)) { 601 port->count++; 602 } 603 port->blocked_open--; 604 if (retval) 605 return retval; 606 607 port->flags |= ASYNC_NORMAL_ACTIVE; 608 func_exit (); 609 return 0; 610} 611 612 613void gs_close(struct tty_struct * tty, struct file * filp) 614{ 615 unsigned long flags; 616 struct gs_port *port; 617 618 func_enter (); 619 620 if (!tty) return; 621 622 port = (struct gs_port *) tty->driver_data; 623 624 if (!port) return; 625 626 if (!port->tty) { 627 /* This seems to happen when this is called from vhangup. */ 628 gs_dprintk (GS_DEBUG_CLOSE, "gs: Odd: port->tty is NULL\n"); 629 port->tty = tty; 630 } 631 632 spin_lock_irqsave(&port->driver_lock, flags); 633 634 if (tty_hung_up_p(filp)) { 635 spin_unlock_irqrestore(&port->driver_lock, flags); 636 if (port->rd->hungup) 637 port->rd->hungup (port); 638 func_exit (); 639 return; 640 } 641 642 if ((tty->count == 1) && (port->count != 1)) { 643 printk(KERN_ERR "gs: gs_close port %p: bad port count;" 644 " tty->count is 1, port count is %d\n", port, port->count); 645 port->count = 1; 646 } 647 if (--port->count < 0) { 648 printk(KERN_ERR "gs: gs_close port %p: bad port count: %d\n", port, port->count); 649 port->count = 0; 650 } 651 652 if (port->count) { 653 gs_dprintk(GS_DEBUG_CLOSE, "gs_close port %p: count: %d\n", port, port->count); 654 spin_unlock_irqrestore(&port->driver_lock, flags); 655 func_exit (); 656 return; 657 } 658 port->flags |= ASYNC_CLOSING; 659 660 /* 661 * Now we wait for the transmit buffer to clear; and we notify 662 * the line discipline to only process XON/XOFF characters. 663 */ 664 tty->closing = 1; 665 /* if (port->closing_wait != ASYNC_CLOSING_WAIT_NONE) 666 tty_wait_until_sent(tty, port->closing_wait); */ 667 668 /* 669 * At this point we stop accepting input. To do this, we 670 * disable the receive line status interrupts, and tell the 671 * interrupt driver to stop checking the data ready bit in the 672 * line status register. 673 */ 674 675 port->rd->disable_rx_interrupts (port); 676 spin_unlock_irqrestore(&port->driver_lock, flags); 677 678 /* close has no way of returning "EINTR", so discard return value */ 679 if (port->closing_wait != ASYNC_CLOSING_WAIT_NONE) 680 gs_wait_tx_flushed (port, port->closing_wait); 681 682 port->flags &= ~GS_ACTIVE; 683 684 if (tty->driver->flush_buffer) 685 tty->driver->flush_buffer(tty); 686 687 tty_ldisc_flush(tty); 688 tty->closing = 0; 689 690 port->event = 0; 691 port->rd->close (port); 692 port->rd->shutdown_port (port); 693 port->tty = NULL; 694 695 if (port->blocked_open) { 696 if (port->close_delay) { 697 spin_unlock_irqrestore(&port->driver_lock, flags); 698 msleep_interruptible(jiffies_to_msecs(port->close_delay)); 699 spin_lock_irqsave(&port->driver_lock, flags); 700 } 701 wake_up_interruptible(&port->open_wait); 702 } 703 port->flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CLOSING | ASYNC_INITIALIZED); 704 wake_up_interruptible(&port->close_wait); 705 706 func_exit (); 707} 708 709 710void gs_set_termios (struct tty_struct * tty, 711 struct ktermios * old_termios) 712{ 713 struct gs_port *port; 714 int baudrate, tmp, rv; 715 struct ktermios *tiosp; 716 717 func_enter(); 718 719 if (!tty) return; 720 721 port = tty->driver_data; 722 723 if (!port) return; 724 if (!port->tty) { 725 /* This seems to happen when this is called after gs_close. */ 726 gs_dprintk (GS_DEBUG_TERMIOS, "gs: Odd: port->tty is NULL\n"); 727 port->tty = tty; 728 } 729 730 731 tiosp = tty->termios; 732 733 if (gs_debug & GS_DEBUG_TERMIOS) { 734 gs_dprintk (GS_DEBUG_TERMIOS, "termios structure (%p):\n", tiosp); 735 } 736 737 /* This is an optimization that is only allowed for dumb cards */ 738 /* Smart cards require knowledge of iflags and oflags too: that 739 might change hardware cooking mode.... */ 740 if (old_termios) { 741 if( (tiosp->c_iflag == old_termios->c_iflag) 742 && (tiosp->c_oflag == old_termios->c_oflag) 743 && (tiosp->c_cflag == old_termios->c_cflag) 744 && (tiosp->c_lflag == old_termios->c_lflag) 745 && (tiosp->c_line == old_termios->c_line) 746 && (memcmp(tiosp->c_cc, old_termios->c_cc, NCC) == 0)) { 747 gs_dprintk(GS_DEBUG_TERMIOS, "gs_set_termios: optimized away\n"); 748 return /* 0 */; 749 } 750 } else 751 gs_dprintk(GS_DEBUG_TERMIOS, "gs_set_termios: no old_termios: " 752 "no optimization\n"); 753 754 if(old_termios && (gs_debug & GS_DEBUG_TERMIOS)) { 755 if(tiosp->c_iflag != old_termios->c_iflag) printk("c_iflag changed\n"); 756 if(tiosp->c_oflag != old_termios->c_oflag) printk("c_oflag changed\n"); 757 if(tiosp->c_cflag != old_termios->c_cflag) printk("c_cflag changed\n"); 758 if(tiosp->c_lflag != old_termios->c_lflag) printk("c_lflag changed\n"); 759 if(tiosp->c_line != old_termios->c_line) printk("c_line changed\n"); 760 if(!memcmp(tiosp->c_cc, old_termios->c_cc, NCC)) printk("c_cc changed\n"); 761 } 762 763 baudrate = tty_get_baud_rate(tty); 764 765 if ((tiosp->c_cflag & CBAUD) == B38400) { 766 if ( (port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_HI) 767 baudrate = 57600; 768 else if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_VHI) 769 baudrate = 115200; 770 else if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_SHI) 771 baudrate = 230400; 772 else if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_WARP) 773 baudrate = 460800; 774 else if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_CUST) 775 baudrate = (port->baud_base / port->custom_divisor); 776 } 777 778 /* I recommend using THIS instead of the mess in termios (and 779 duplicating the above code). Next we should create a clean 780 interface towards this variable. If your card supports arbitrary 781 baud rates, (e.g. CD1400 or 16550 based cards) then everything 782 will be very easy..... */ 783 port->baud = baudrate; 784 785 /* Two timer ticks seems enough to wakeup something like SLIP driver */ 786 /* Baudrate/10 is cps. Divide by HZ to get chars per tick. */ 787 tmp = (baudrate / 10 / HZ) * 2; 788 789 if (tmp < 0) tmp = 0; 790 if (tmp >= SERIAL_XMIT_SIZE) tmp = SERIAL_XMIT_SIZE-1; 791 792 port->wakeup_chars = tmp; 793 794 /* We should really wait for the characters to be all sent before 795 changing the settings. -- CAL */ 796 rv = gs_wait_tx_flushed (port, MAX_SCHEDULE_TIMEOUT); 797 if (rv < 0) return /* rv */; 798 799 rv = port->rd->set_real_termios(port); 800 if (rv < 0) return /* rv */; 801 802 if ((!old_termios || 803 (old_termios->c_cflag & CRTSCTS)) && 804 !( tiosp->c_cflag & CRTSCTS)) { 805 tty->stopped = 0; 806 gs_start(tty); 807 } 808 809#ifdef tytso_patch_94Nov25_1726 810 /* This "makes sense", Why is it commented out? */ 811 812 if (!(old_termios->c_cflag & CLOCAL) && 813 (tty->termios->c_cflag & CLOCAL)) 814 wake_up_interruptible(&port->gs.open_wait); 815#endif 816 817 func_exit(); 818 return /* 0 */; 819} 820 821 822 823/* Must be called with interrupts enabled */ 824int gs_init_port(struct gs_port *port) 825{ 826 unsigned long flags; 827 828 func_enter (); 829 830 if (port->flags & ASYNC_INITIALIZED) { 831 func_exit (); 832 return 0; 833 } 834 if (!port->xmit_buf) { 835 /* We may sleep in get_zeroed_page() */ 836 unsigned long tmp; 837 838 tmp = get_zeroed_page(GFP_KERNEL); 839 spin_lock_irqsave (&port->driver_lock, flags); 840 if (port->xmit_buf) 841 free_page (tmp); 842 else 843 port->xmit_buf = (unsigned char *) tmp; 844 spin_unlock_irqrestore(&port->driver_lock, flags); 845 if (!port->xmit_buf) { 846 func_exit (); 847 return -ENOMEM; 848 } 849 } 850 851 spin_lock_irqsave (&port->driver_lock, flags); 852 if (port->tty) 853 clear_bit(TTY_IO_ERROR, &port->tty->flags); 854 mutex_init(&port->port_write_mutex); 855 port->xmit_cnt = port->xmit_head = port->xmit_tail = 0; 856 spin_unlock_irqrestore(&port->driver_lock, flags); 857 gs_set_termios(port->tty, NULL); 858 spin_lock_irqsave (&port->driver_lock, flags); 859 port->flags |= ASYNC_INITIALIZED; 860 port->flags &= ~GS_TX_INTEN; 861 862 spin_unlock_irqrestore(&port->driver_lock, flags); 863 func_exit (); 864 return 0; 865} 866 867 868int gs_setserial(struct gs_port *port, struct serial_struct __user *sp) 869{ 870 struct serial_struct sio; 871 872 if (copy_from_user(&sio, sp, sizeof(struct serial_struct))) 873 return(-EFAULT); 874 875 if (!capable(CAP_SYS_ADMIN)) { 876 if ((sio.baud_base != port->baud_base) || 877 (sio.close_delay != port->close_delay) || 878 ((sio.flags & ~ASYNC_USR_MASK) != 879 (port->flags & ~ASYNC_USR_MASK))) 880 return(-EPERM); 881 } 882 883 port->flags = (port->flags & ~ASYNC_USR_MASK) | 884 (sio.flags & ASYNC_USR_MASK); 885 886 port->baud_base = sio.baud_base; 887 port->close_delay = sio.close_delay; 888 port->closing_wait = sio.closing_wait; 889 port->custom_divisor = sio.custom_divisor; 890 891 gs_set_termios (port->tty, NULL); 892 893 return 0; 894} 895 896 897/*****************************************************************************/ 898 899/* 900 * Generate the serial struct info. 901 */ 902 903int gs_getserial(struct gs_port *port, struct serial_struct __user *sp) 904{ 905 struct serial_struct sio; 906 907 memset(&sio, 0, sizeof(struct serial_struct)); 908 sio.flags = port->flags; 909 sio.baud_base = port->baud_base; 910 sio.close_delay = port->close_delay; 911 sio.closing_wait = port->closing_wait; 912 sio.custom_divisor = port->custom_divisor; 913 sio.hub6 = 0; 914 915 /* If you want you can override these. */ 916 sio.type = PORT_UNKNOWN; 917 sio.xmit_fifo_size = -1; 918 sio.line = -1; 919 sio.port = -1; 920 sio.irq = -1; 921 922 if (port->rd->getserial) 923 port->rd->getserial (port, &sio); 924 925 if (copy_to_user(sp, &sio, sizeof(struct serial_struct))) 926 return -EFAULT; 927 return 0; 928 929} 930 931 932void gs_got_break(struct gs_port *port) 933{ 934 func_enter (); 935 936 tty_insert_flip_char(port->tty, 0, TTY_BREAK); 937 tty_schedule_flip(port->tty); 938 if (port->flags & ASYNC_SAK) { 939 do_SAK (port->tty); 940 } 941 942 func_exit (); 943} 944 945 946EXPORT_SYMBOL(gs_put_char); 947EXPORT_SYMBOL(gs_write); 948EXPORT_SYMBOL(gs_write_room); 949EXPORT_SYMBOL(gs_chars_in_buffer); 950EXPORT_SYMBOL(gs_flush_buffer); 951EXPORT_SYMBOL(gs_flush_chars); 952EXPORT_SYMBOL(gs_stop); 953EXPORT_SYMBOL(gs_start); 954EXPORT_SYMBOL(gs_hangup); 955EXPORT_SYMBOL(gs_block_til_ready); 956EXPORT_SYMBOL(gs_close); 957EXPORT_SYMBOL(gs_set_termios); 958EXPORT_SYMBOL(gs_init_port); 959EXPORT_SYMBOL(gs_setserial); 960EXPORT_SYMBOL(gs_getserial); 961EXPORT_SYMBOL(gs_got_break); 962 963MODULE_LICENSE("GPL"); 964