1/************************************************************************ 2 * Copyright 2003 Digi International (www.digi.com) 3 * 4 * Copyright (C) 2004 IBM Corporation. All rights reserved. 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License as published by 8 * the Free Software Foundation; either version 2, or (at your option) 9 * any later version. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY, EXPRESS OR IMPLIED; without even the 13 * implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR 14 * PURPOSE. See the GNU General Public License for more details. 15 * 16 * Contact Information: 17 * Scott H Kilau <Scott_Kilau@digi.com> 18 * Ananda Venkatarman <mansarov@us.ibm.com> 19 * Modifications: 20 * 01/19/06: changed jsm_input routine to use the dynamically allocated 21 * tty_buffer changes. Contributors: Scott Kilau and Ananda V. 22 ***********************************************************************/ 23#include <linux/tty.h> 24#include <linux/tty_flip.h> 25#include <linux/serial_reg.h> 26#include <linux/delay.h> /* For udelay */ 27#include <linux/pci.h> 28#include <linux/slab.h> 29 30#include "jsm.h" 31 32static DECLARE_BITMAP(linemap, MAXLINES); 33 34static void jsm_carrier(struct jsm_channel *ch); 35 36static inline int jsm_get_mstat(struct jsm_channel *ch) 37{ 38 unsigned char mstat; 39 unsigned result; 40 41 jsm_dbg(IOCTL, &ch->ch_bd->pci_dev, "start\n"); 42 43 mstat = (ch->ch_mostat | ch->ch_mistat); 44 45 result = 0; 46 47 if (mstat & UART_MCR_DTR) 48 result |= TIOCM_DTR; 49 if (mstat & UART_MCR_RTS) 50 result |= TIOCM_RTS; 51 if (mstat & UART_MSR_CTS) 52 result |= TIOCM_CTS; 53 if (mstat & UART_MSR_DSR) 54 result |= TIOCM_DSR; 55 if (mstat & UART_MSR_RI) 56 result |= TIOCM_RI; 57 if (mstat & UART_MSR_DCD) 58 result |= TIOCM_CD; 59 60 jsm_dbg(IOCTL, &ch->ch_bd->pci_dev, "finish\n"); 61 return result; 62} 63 64static unsigned int jsm_tty_tx_empty(struct uart_port *port) 65{ 66 return TIOCSER_TEMT; 67} 68 69/* 70 * Return modem signals to ld. 71 */ 72static unsigned int jsm_tty_get_mctrl(struct uart_port *port) 73{ 74 int result; 75 struct jsm_channel *channel = 76 container_of(port, struct jsm_channel, uart_port); 77 78 jsm_dbg(IOCTL, &channel->ch_bd->pci_dev, "start\n"); 79 80 result = jsm_get_mstat(channel); 81 82 if (result < 0) 83 return -ENXIO; 84 85 jsm_dbg(IOCTL, &channel->ch_bd->pci_dev, "finish\n"); 86 87 return result; 88} 89 90/* 91 * jsm_set_modem_info() 92 * 93 * Set modem signals, called by ld. 94 */ 95static void jsm_tty_set_mctrl(struct uart_port *port, unsigned int mctrl) 96{ 97 struct jsm_channel *channel = 98 container_of(port, struct jsm_channel, uart_port); 99 100 jsm_dbg(IOCTL, &channel->ch_bd->pci_dev, "start\n"); 101 102 if (mctrl & TIOCM_RTS) 103 channel->ch_mostat |= UART_MCR_RTS; 104 else 105 channel->ch_mostat &= ~UART_MCR_RTS; 106 107 if (mctrl & TIOCM_DTR) 108 channel->ch_mostat |= UART_MCR_DTR; 109 else 110 channel->ch_mostat &= ~UART_MCR_DTR; 111 112 channel->ch_bd->bd_ops->assert_modem_signals(channel); 113 114 jsm_dbg(IOCTL, &channel->ch_bd->pci_dev, "finish\n"); 115 udelay(10); 116} 117 118/* 119 * jsm_tty_write() 120 * 121 * Take data from the user or kernel and send it out to the FEP. 122 * In here exists all the Transparent Print magic as well. 123 */ 124static void jsm_tty_write(struct uart_port *port) 125{ 126 struct jsm_channel *channel; 127 channel = container_of(port, struct jsm_channel, uart_port); 128 channel->ch_bd->bd_ops->copy_data_from_queue_to_uart(channel); 129} 130 131static void jsm_tty_start_tx(struct uart_port *port) 132{ 133 struct jsm_channel *channel = 134 container_of(port, struct jsm_channel, uart_port); 135 136 jsm_dbg(IOCTL, &channel->ch_bd->pci_dev, "start\n"); 137 138 channel->ch_flags &= ~(CH_STOP); 139 jsm_tty_write(port); 140 141 jsm_dbg(IOCTL, &channel->ch_bd->pci_dev, "finish\n"); 142} 143 144static void jsm_tty_stop_tx(struct uart_port *port) 145{ 146 struct jsm_channel *channel = 147 container_of(port, struct jsm_channel, uart_port); 148 149 jsm_dbg(IOCTL, &channel->ch_bd->pci_dev, "start\n"); 150 151 channel->ch_flags |= (CH_STOP); 152 153 jsm_dbg(IOCTL, &channel->ch_bd->pci_dev, "finish\n"); 154} 155 156static void jsm_tty_send_xchar(struct uart_port *port, char ch) 157{ 158 unsigned long lock_flags; 159 struct jsm_channel *channel = 160 container_of(port, struct jsm_channel, uart_port); 161 struct ktermios *termios; 162 163 spin_lock_irqsave(&port->lock, lock_flags); 164 termios = &port->state->port.tty->termios; 165 if (ch == termios->c_cc[VSTART]) 166 channel->ch_bd->bd_ops->send_start_character(channel); 167 168 if (ch == termios->c_cc[VSTOP]) 169 channel->ch_bd->bd_ops->send_stop_character(channel); 170 spin_unlock_irqrestore(&port->lock, lock_flags); 171} 172 173static void jsm_tty_stop_rx(struct uart_port *port) 174{ 175 struct jsm_channel *channel = 176 container_of(port, struct jsm_channel, uart_port); 177 178 channel->ch_bd->bd_ops->disable_receiver(channel); 179} 180 181static void jsm_tty_break(struct uart_port *port, int break_state) 182{ 183 unsigned long lock_flags; 184 struct jsm_channel *channel = 185 container_of(port, struct jsm_channel, uart_port); 186 187 spin_lock_irqsave(&port->lock, lock_flags); 188 if (break_state == -1) 189 channel->ch_bd->bd_ops->send_break(channel); 190 else 191 channel->ch_bd->bd_ops->clear_break(channel); 192 193 spin_unlock_irqrestore(&port->lock, lock_flags); 194} 195 196static int jsm_tty_open(struct uart_port *port) 197{ 198 struct jsm_board *brd; 199 struct jsm_channel *channel = 200 container_of(port, struct jsm_channel, uart_port); 201 struct ktermios *termios; 202 203 /* Get board pointer from our array of majors we have allocated */ 204 brd = channel->ch_bd; 205 206 /* 207 * Allocate channel buffers for read/write/error. 208 * Set flag, so we don't get trounced on. 209 */ 210 channel->ch_flags |= (CH_OPENING); 211 212 /* Drop locks, as malloc with GFP_KERNEL can sleep */ 213 214 if (!channel->ch_rqueue) { 215 channel->ch_rqueue = kzalloc(RQUEUESIZE, GFP_KERNEL); 216 if (!channel->ch_rqueue) { 217 jsm_dbg(INIT, &channel->ch_bd->pci_dev, 218 "unable to allocate read queue buf\n"); 219 return -ENOMEM; 220 } 221 } 222 if (!channel->ch_equeue) { 223 channel->ch_equeue = kzalloc(EQUEUESIZE, GFP_KERNEL); 224 if (!channel->ch_equeue) { 225 jsm_dbg(INIT, &channel->ch_bd->pci_dev, 226 "unable to allocate error queue buf\n"); 227 return -ENOMEM; 228 } 229 } 230 231 channel->ch_flags &= ~(CH_OPENING); 232 /* 233 * Initialize if neither terminal is open. 234 */ 235 jsm_dbg(OPEN, &channel->ch_bd->pci_dev, 236 "jsm_open: initializing channel in open...\n"); 237 238 /* 239 * Flush input queues. 240 */ 241 channel->ch_r_head = channel->ch_r_tail = 0; 242 channel->ch_e_head = channel->ch_e_tail = 0; 243 244 brd->bd_ops->flush_uart_write(channel); 245 brd->bd_ops->flush_uart_read(channel); 246 247 channel->ch_flags = 0; 248 channel->ch_cached_lsr = 0; 249 channel->ch_stops_sent = 0; 250 251 termios = &port->state->port.tty->termios; 252 channel->ch_c_cflag = termios->c_cflag; 253 channel->ch_c_iflag = termios->c_iflag; 254 channel->ch_c_oflag = termios->c_oflag; 255 channel->ch_c_lflag = termios->c_lflag; 256 channel->ch_startc = termios->c_cc[VSTART]; 257 channel->ch_stopc = termios->c_cc[VSTOP]; 258 259 /* Tell UART to init itself */ 260 brd->bd_ops->uart_init(channel); 261 262 /* 263 * Run param in case we changed anything 264 */ 265 brd->bd_ops->param(channel); 266 267 jsm_carrier(channel); 268 269 channel->ch_open_count++; 270 271 jsm_dbg(OPEN, &channel->ch_bd->pci_dev, "finish\n"); 272 return 0; 273} 274 275static void jsm_tty_close(struct uart_port *port) 276{ 277 struct jsm_board *bd; 278 struct ktermios *ts; 279 struct jsm_channel *channel = 280 container_of(port, struct jsm_channel, uart_port); 281 282 jsm_dbg(CLOSE, &channel->ch_bd->pci_dev, "start\n"); 283 284 bd = channel->ch_bd; 285 ts = &port->state->port.tty->termios; 286 287 channel->ch_flags &= ~(CH_STOPI); 288 289 channel->ch_open_count--; 290 291 /* 292 * If we have HUPCL set, lower DTR and RTS 293 */ 294 if (channel->ch_c_cflag & HUPCL) { 295 jsm_dbg(CLOSE, &channel->ch_bd->pci_dev, 296 "Close. HUPCL set, dropping DTR/RTS\n"); 297 298 /* Drop RTS/DTR */ 299 channel->ch_mostat &= ~(UART_MCR_DTR | UART_MCR_RTS); 300 bd->bd_ops->assert_modem_signals(channel); 301 } 302 303 /* Turn off UART interrupts for this port */ 304 channel->ch_bd->bd_ops->uart_off(channel); 305 306 jsm_dbg(CLOSE, &channel->ch_bd->pci_dev, "finish\n"); 307} 308 309static void jsm_tty_set_termios(struct uart_port *port, 310 struct ktermios *termios, 311 struct ktermios *old_termios) 312{ 313 unsigned long lock_flags; 314 struct jsm_channel *channel = 315 container_of(port, struct jsm_channel, uart_port); 316 317 spin_lock_irqsave(&port->lock, lock_flags); 318 channel->ch_c_cflag = termios->c_cflag; 319 channel->ch_c_iflag = termios->c_iflag; 320 channel->ch_c_oflag = termios->c_oflag; 321 channel->ch_c_lflag = termios->c_lflag; 322 channel->ch_startc = termios->c_cc[VSTART]; 323 channel->ch_stopc = termios->c_cc[VSTOP]; 324 325 channel->ch_bd->bd_ops->param(channel); 326 jsm_carrier(channel); 327 spin_unlock_irqrestore(&port->lock, lock_flags); 328} 329 330static const char *jsm_tty_type(struct uart_port *port) 331{ 332 return "jsm"; 333} 334 335static void jsm_tty_release_port(struct uart_port *port) 336{ 337} 338 339static int jsm_tty_request_port(struct uart_port *port) 340{ 341 return 0; 342} 343 344static void jsm_config_port(struct uart_port *port, int flags) 345{ 346 port->type = PORT_JSM; 347} 348 349static struct uart_ops jsm_ops = { 350 .tx_empty = jsm_tty_tx_empty, 351 .set_mctrl = jsm_tty_set_mctrl, 352 .get_mctrl = jsm_tty_get_mctrl, 353 .stop_tx = jsm_tty_stop_tx, 354 .start_tx = jsm_tty_start_tx, 355 .send_xchar = jsm_tty_send_xchar, 356 .stop_rx = jsm_tty_stop_rx, 357 .break_ctl = jsm_tty_break, 358 .startup = jsm_tty_open, 359 .shutdown = jsm_tty_close, 360 .set_termios = jsm_tty_set_termios, 361 .type = jsm_tty_type, 362 .release_port = jsm_tty_release_port, 363 .request_port = jsm_tty_request_port, 364 .config_port = jsm_config_port, 365}; 366 367/* 368 * jsm_tty_init() 369 * 370 * Init the tty subsystem. Called once per board after board has been 371 * downloaded and init'ed. 372 */ 373int jsm_tty_init(struct jsm_board *brd) 374{ 375 int i; 376 void __iomem *vaddr; 377 struct jsm_channel *ch; 378 379 if (!brd) 380 return -ENXIO; 381 382 jsm_dbg(INIT, &brd->pci_dev, "start\n"); 383 384 /* 385 * Initialize board structure elements. 386 */ 387 388 brd->nasync = brd->maxports; 389 390 /* 391 * Allocate channel memory that might not have been allocated 392 * when the driver was first loaded. 393 */ 394 for (i = 0; i < brd->nasync; i++) { 395 if (!brd->channels[i]) { 396 397 /* 398 * Okay to malloc with GFP_KERNEL, we are not at 399 * interrupt context, and there are no locks held. 400 */ 401 brd->channels[i] = kzalloc(sizeof(struct jsm_channel), GFP_KERNEL); 402 if (!brd->channels[i]) { 403 jsm_dbg(CORE, &brd->pci_dev, 404 "%s:%d Unable to allocate memory for channel struct\n", 405 __FILE__, __LINE__); 406 } 407 } 408 } 409 410 ch = brd->channels[0]; 411 vaddr = brd->re_map_membase; 412 413 /* Set up channel variables */ 414 for (i = 0; i < brd->nasync; i++, ch = brd->channels[i]) { 415 416 if (!brd->channels[i]) 417 continue; 418 419 spin_lock_init(&ch->ch_lock); 420 421 if (brd->bd_uart_offset == 0x200) 422 ch->ch_neo_uart = vaddr + (brd->bd_uart_offset * i); 423 else 424 ch->ch_cls_uart = vaddr + (brd->bd_uart_offset * i); 425 426 ch->ch_bd = brd; 427 ch->ch_portnum = i; 428 429 /* .25 second delay */ 430 ch->ch_close_delay = 250; 431 432 init_waitqueue_head(&ch->ch_flags_wait); 433 } 434 435 jsm_dbg(INIT, &brd->pci_dev, "finish\n"); 436 return 0; 437} 438 439int jsm_uart_port_init(struct jsm_board *brd) 440{ 441 int i, rc; 442 unsigned int line; 443 struct jsm_channel *ch; 444 445 if (!brd) 446 return -ENXIO; 447 448 jsm_dbg(INIT, &brd->pci_dev, "start\n"); 449 450 /* 451 * Initialize board structure elements. 452 */ 453 454 brd->nasync = brd->maxports; 455 456 /* Set up channel variables */ 457 for (i = 0; i < brd->nasync; i++, ch = brd->channels[i]) { 458 459 if (!brd->channels[i]) 460 continue; 461 462 brd->channels[i]->uart_port.irq = brd->irq; 463 brd->channels[i]->uart_port.uartclk = 14745600; 464 brd->channels[i]->uart_port.type = PORT_JSM; 465 brd->channels[i]->uart_port.iotype = UPIO_MEM; 466 brd->channels[i]->uart_port.membase = brd->re_map_membase; 467 brd->channels[i]->uart_port.fifosize = 16; 468 brd->channels[i]->uart_port.ops = &jsm_ops; 469 line = find_first_zero_bit(linemap, MAXLINES); 470 if (line >= MAXLINES) { 471 printk(KERN_INFO "jsm: linemap is full, added device failed\n"); 472 continue; 473 } else 474 set_bit(line, linemap); 475 brd->channels[i]->uart_port.line = line; 476 rc = uart_add_one_port (&jsm_uart_driver, &brd->channels[i]->uart_port); 477 if (rc){ 478 printk(KERN_INFO "jsm: Port %d failed. Aborting...\n", i); 479 return rc; 480 } 481 else 482 printk(KERN_INFO "jsm: Port %d added\n", i); 483 } 484 485 jsm_dbg(INIT, &brd->pci_dev, "finish\n"); 486 return 0; 487} 488 489int jsm_remove_uart_port(struct jsm_board *brd) 490{ 491 int i; 492 struct jsm_channel *ch; 493 494 if (!brd) 495 return -ENXIO; 496 497 jsm_dbg(INIT, &brd->pci_dev, "start\n"); 498 499 /* 500 * Initialize board structure elements. 501 */ 502 503 brd->nasync = brd->maxports; 504 505 /* Set up channel variables */ 506 for (i = 0; i < brd->nasync; i++) { 507 508 if (!brd->channels[i]) 509 continue; 510 511 ch = brd->channels[i]; 512 513 clear_bit(ch->uart_port.line, linemap); 514 uart_remove_one_port(&jsm_uart_driver, &brd->channels[i]->uart_port); 515 } 516 517 jsm_dbg(INIT, &brd->pci_dev, "finish\n"); 518 return 0; 519} 520 521void jsm_input(struct jsm_channel *ch) 522{ 523 struct jsm_board *bd; 524 struct tty_struct *tp; 525 struct tty_port *port; 526 u32 rmask; 527 u16 head; 528 u16 tail; 529 int data_len; 530 unsigned long lock_flags; 531 int len = 0; 532 int n = 0; 533 int s = 0; 534 int i = 0; 535 536 jsm_dbg(READ, &ch->ch_bd->pci_dev, "start\n"); 537 538 if (!ch) 539 return; 540 541 port = &ch->uart_port.state->port; 542 tp = port->tty; 543 544 bd = ch->ch_bd; 545 if(!bd) 546 return; 547 548 spin_lock_irqsave(&ch->ch_lock, lock_flags); 549 550 /* 551 *Figure the number of characters in the buffer. 552 *Exit immediately if none. 553 */ 554 555 rmask = RQUEUEMASK; 556 557 head = ch->ch_r_head & rmask; 558 tail = ch->ch_r_tail & rmask; 559 560 data_len = (head - tail) & rmask; 561 if (data_len == 0) { 562 spin_unlock_irqrestore(&ch->ch_lock, lock_flags); 563 return; 564 } 565 566 jsm_dbg(READ, &ch->ch_bd->pci_dev, "start\n"); 567 568 /* 569 *If the device is not open, or CREAD is off, flush 570 *input data and return immediately. 571 */ 572 if (!tp || 573 !(tp->termios.c_cflag & CREAD) ) { 574 575 jsm_dbg(READ, &ch->ch_bd->pci_dev, 576 "input. dropping %d bytes on port %d...\n", 577 data_len, ch->ch_portnum); 578 ch->ch_r_head = tail; 579 580 /* Force queue flow control to be released, if needed */ 581 jsm_check_queue_flow_control(ch); 582 583 spin_unlock_irqrestore(&ch->ch_lock, lock_flags); 584 return; 585 } 586 587 /* 588 * If we are throttled, simply don't read any data. 589 */ 590 if (ch->ch_flags & CH_STOPI) { 591 spin_unlock_irqrestore(&ch->ch_lock, lock_flags); 592 jsm_dbg(READ, &ch->ch_bd->pci_dev, 593 "Port %d throttled, not reading any data. head: %x tail: %x\n", 594 ch->ch_portnum, head, tail); 595 return; 596 } 597 598 jsm_dbg(READ, &ch->ch_bd->pci_dev, "start 2\n"); 599 600 len = tty_buffer_request_room(port, data_len); 601 n = len; 602 603 /* 604 * n now contains the most amount of data we can copy, 605 * bounded either by the flip buffer size or the amount 606 * of data the card actually has pending... 607 */ 608 while (n) { 609 s = ((head >= tail) ? head : RQUEUESIZE) - tail; 610 s = min(s, n); 611 612 if (s <= 0) 613 break; 614 615 /* 616 * If conditions are such that ld needs to see all 617 * UART errors, we will have to walk each character 618 * and error byte and send them to the buffer one at 619 * a time. 620 */ 621 622 if (I_PARMRK(tp) || I_BRKINT(tp) || I_INPCK(tp)) { 623 for (i = 0; i < s; i++) { 624 /* 625 * Give the Linux ld the flags in the 626 * format it likes. 627 */ 628 if (*(ch->ch_equeue +tail +i) & UART_LSR_BI) 629 tty_insert_flip_char(port, *(ch->ch_rqueue +tail +i), TTY_BREAK); 630 else if (*(ch->ch_equeue +tail +i) & UART_LSR_PE) 631 tty_insert_flip_char(port, *(ch->ch_rqueue +tail +i), TTY_PARITY); 632 else if (*(ch->ch_equeue +tail +i) & UART_LSR_FE) 633 tty_insert_flip_char(port, *(ch->ch_rqueue +tail +i), TTY_FRAME); 634 else 635 tty_insert_flip_char(port, *(ch->ch_rqueue +tail +i), TTY_NORMAL); 636 } 637 } else { 638 tty_insert_flip_string(port, ch->ch_rqueue + tail, s); 639 } 640 tail += s; 641 n -= s; 642 /* Flip queue if needed */ 643 tail &= rmask; 644 } 645 646 ch->ch_r_tail = tail & rmask; 647 ch->ch_e_tail = tail & rmask; 648 jsm_check_queue_flow_control(ch); 649 spin_unlock_irqrestore(&ch->ch_lock, lock_flags); 650 651 /* Tell the tty layer its okay to "eat" the data now */ 652 tty_flip_buffer_push(port); 653 654 jsm_dbg(IOCTL, &ch->ch_bd->pci_dev, "finish\n"); 655} 656 657static void jsm_carrier(struct jsm_channel *ch) 658{ 659 struct jsm_board *bd; 660 661 int virt_carrier = 0; 662 int phys_carrier = 0; 663 664 jsm_dbg(CARR, &ch->ch_bd->pci_dev, "start\n"); 665 if (!ch) 666 return; 667 668 bd = ch->ch_bd; 669 670 if (!bd) 671 return; 672 673 if (ch->ch_mistat & UART_MSR_DCD) { 674 jsm_dbg(CARR, &ch->ch_bd->pci_dev, "mistat: %x D_CD: %x\n", 675 ch->ch_mistat, ch->ch_mistat & UART_MSR_DCD); 676 phys_carrier = 1; 677 } 678 679 if (ch->ch_c_cflag & CLOCAL) 680 virt_carrier = 1; 681 682 jsm_dbg(CARR, &ch->ch_bd->pci_dev, "DCD: physical: %d virt: %d\n", 683 phys_carrier, virt_carrier); 684 685 /* 686 * Test for a VIRTUAL carrier transition to HIGH. 687 */ 688 if (((ch->ch_flags & CH_FCAR) == 0) && (virt_carrier == 1)) { 689 690 /* 691 * When carrier rises, wake any threads waiting 692 * for carrier in the open routine. 693 */ 694 695 jsm_dbg(CARR, &ch->ch_bd->pci_dev, "carrier: virt DCD rose\n"); 696 697 if (waitqueue_active(&(ch->ch_flags_wait))) 698 wake_up_interruptible(&ch->ch_flags_wait); 699 } 700 701 /* 702 * Test for a PHYSICAL carrier transition to HIGH. 703 */ 704 if (((ch->ch_flags & CH_CD) == 0) && (phys_carrier == 1)) { 705 706 /* 707 * When carrier rises, wake any threads waiting 708 * for carrier in the open routine. 709 */ 710 711 jsm_dbg(CARR, &ch->ch_bd->pci_dev, 712 "carrier: physical DCD rose\n"); 713 714 if (waitqueue_active(&(ch->ch_flags_wait))) 715 wake_up_interruptible(&ch->ch_flags_wait); 716 } 717 718 /* 719 * Test for a PHYSICAL transition to low, so long as we aren't 720 * currently ignoring physical transitions (which is what "virtual 721 * carrier" indicates). 722 * 723 * The transition of the virtual carrier to low really doesn't 724 * matter... it really only means "ignore carrier state", not 725 * "make pretend that carrier is there". 726 */ 727 if ((virt_carrier == 0) && ((ch->ch_flags & CH_CD) != 0) 728 && (phys_carrier == 0)) { 729 /* 730 * When carrier drops: 731 * 732 * Drop carrier on all open units. 733 * 734 * Flush queues, waking up any task waiting in the 735 * line discipline. 736 * 737 * Send a hangup to the control terminal. 738 * 739 * Enable all select calls. 740 */ 741 if (waitqueue_active(&(ch->ch_flags_wait))) 742 wake_up_interruptible(&ch->ch_flags_wait); 743 } 744 745 /* 746 * Make sure that our cached values reflect the current reality. 747 */ 748 if (virt_carrier == 1) 749 ch->ch_flags |= CH_FCAR; 750 else 751 ch->ch_flags &= ~CH_FCAR; 752 753 if (phys_carrier == 1) 754 ch->ch_flags |= CH_CD; 755 else 756 ch->ch_flags &= ~CH_CD; 757} 758 759 760void jsm_check_queue_flow_control(struct jsm_channel *ch) 761{ 762 struct board_ops *bd_ops = ch->ch_bd->bd_ops; 763 int qleft; 764 765 /* Store how much space we have left in the queue */ 766 if ((qleft = ch->ch_r_tail - ch->ch_r_head - 1) < 0) 767 qleft += RQUEUEMASK + 1; 768 769 /* 770 * Check to see if we should enforce flow control on our queue because 771 * the ld (or user) isn't reading data out of our queue fast enuf. 772 * 773 * NOTE: This is done based on what the current flow control of the 774 * port is set for. 775 * 776 * 1) HWFLOW (RTS) - Turn off the UART's Receive interrupt. 777 * This will cause the UART's FIFO to back up, and force 778 * the RTS signal to be dropped. 779 * 2) SWFLOW (IXOFF) - Keep trying to send a stop character to 780 * the other side, in hopes it will stop sending data to us. 781 * 3) NONE - Nothing we can do. We will simply drop any extra data 782 * that gets sent into us when the queue fills up. 783 */ 784 if (qleft < 256) { 785 /* HWFLOW */ 786 if (ch->ch_c_cflag & CRTSCTS) { 787 if(!(ch->ch_flags & CH_RECEIVER_OFF)) { 788 bd_ops->disable_receiver(ch); 789 ch->ch_flags |= (CH_RECEIVER_OFF); 790 jsm_dbg(READ, &ch->ch_bd->pci_dev, 791 "Internal queue hit hilevel mark (%d)! Turning off interrupts\n", 792 qleft); 793 } 794 } 795 /* SWFLOW */ 796 else if (ch->ch_c_iflag & IXOFF) { 797 if (ch->ch_stops_sent <= MAX_STOPS_SENT) { 798 bd_ops->send_stop_character(ch); 799 ch->ch_stops_sent++; 800 jsm_dbg(READ, &ch->ch_bd->pci_dev, 801 "Sending stop char! Times sent: %x\n", 802 ch->ch_stops_sent); 803 } 804 } 805 } 806 807 /* 808 * Check to see if we should unenforce flow control because 809 * ld (or user) finally read enuf data out of our queue. 810 * 811 * NOTE: This is done based on what the current flow control of the 812 * port is set for. 813 * 814 * 1) HWFLOW (RTS) - Turn back on the UART's Receive interrupt. 815 * This will cause the UART's FIFO to raise RTS back up, 816 * which will allow the other side to start sending data again. 817 * 2) SWFLOW (IXOFF) - Send a start character to 818 * the other side, so it will start sending data to us again. 819 * 3) NONE - Do nothing. Since we didn't do anything to turn off the 820 * other side, we don't need to do anything now. 821 */ 822 if (qleft > (RQUEUESIZE / 2)) { 823 /* HWFLOW */ 824 if (ch->ch_c_cflag & CRTSCTS) { 825 if (ch->ch_flags & CH_RECEIVER_OFF) { 826 bd_ops->enable_receiver(ch); 827 ch->ch_flags &= ~(CH_RECEIVER_OFF); 828 jsm_dbg(READ, &ch->ch_bd->pci_dev, 829 "Internal queue hit lowlevel mark (%d)! Turning on interrupts\n", 830 qleft); 831 } 832 } 833 /* SWFLOW */ 834 else if (ch->ch_c_iflag & IXOFF && ch->ch_stops_sent) { 835 ch->ch_stops_sent = 0; 836 bd_ops->send_start_character(ch); 837 jsm_dbg(READ, &ch->ch_bd->pci_dev, 838 "Sending start char!\n"); 839 } 840 } 841} 842