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 * You should have received a copy of the GNU General Public License 17 * along with this program; if not, write to the Free Software 18 * Foundation, Inc., 59 * Temple Place - Suite 330, Boston, 19 * MA 02111-1307, USA. 20 * 21 * Contact Information: 22 * Scott H Kilau <Scott_Kilau@digi.com> 23 * Ananda Venkatarman <mansarov@us.ibm.com> 24 * Modifications: 25 * 01/19/06: changed jsm_input routine to use the dynamically allocated 26 * tty_buffer changes. Contributors: Scott Kilau and Ananda V. 27 ***********************************************************************/ 28#include <linux/tty.h> 29#include <linux/tty_flip.h> 30#include <linux/serial_reg.h> 31#include <linux/delay.h> /* For udelay */ 32#include <linux/pci.h> 33#include <linux/slab.h> 34 35#include "jsm.h" 36 37static DECLARE_BITMAP(linemap, MAXLINES); 38 39static void jsm_carrier(struct jsm_channel *ch); 40 41static inline int jsm_get_mstat(struct jsm_channel *ch) 42{ 43 unsigned char mstat; 44 unsigned result; 45 46 jsm_printk(IOCTL, INFO, &ch->ch_bd->pci_dev, "start\n"); 47 48 mstat = (ch->ch_mostat | ch->ch_mistat); 49 50 result = 0; 51 52 if (mstat & UART_MCR_DTR) 53 result |= TIOCM_DTR; 54 if (mstat & UART_MCR_RTS) 55 result |= TIOCM_RTS; 56 if (mstat & UART_MSR_CTS) 57 result |= TIOCM_CTS; 58 if (mstat & UART_MSR_DSR) 59 result |= TIOCM_DSR; 60 if (mstat & UART_MSR_RI) 61 result |= TIOCM_RI; 62 if (mstat & UART_MSR_DCD) 63 result |= TIOCM_CD; 64 65 jsm_printk(IOCTL, INFO, &ch->ch_bd->pci_dev, "finish\n"); 66 return result; 67} 68 69static unsigned int jsm_tty_tx_empty(struct uart_port *port) 70{ 71 return TIOCSER_TEMT; 72} 73 74/* 75 * Return modem signals to ld. 76 */ 77static unsigned int jsm_tty_get_mctrl(struct uart_port *port) 78{ 79 int result; 80 struct jsm_channel *channel = (struct jsm_channel *)port; 81 82 jsm_printk(IOCTL, INFO, &channel->ch_bd->pci_dev, "start\n"); 83 84 result = jsm_get_mstat(channel); 85 86 if (result < 0) 87 return -ENXIO; 88 89 jsm_printk(IOCTL, INFO, &channel->ch_bd->pci_dev, "finish\n"); 90 91 return result; 92} 93 94/* 95 * jsm_set_modem_info() 96 * 97 * Set modem signals, called by ld. 98 */ 99static void jsm_tty_set_mctrl(struct uart_port *port, unsigned int mctrl) 100{ 101 struct jsm_channel *channel = (struct jsm_channel *)port; 102 103 jsm_printk(IOCTL, INFO, &channel->ch_bd->pci_dev, "start\n"); 104 105 if (mctrl & TIOCM_RTS) 106 channel->ch_mostat |= UART_MCR_RTS; 107 else 108 channel->ch_mostat &= ~UART_MCR_RTS; 109 110 if (mctrl & TIOCM_DTR) 111 channel->ch_mostat |= UART_MCR_DTR; 112 else 113 channel->ch_mostat &= ~UART_MCR_DTR; 114 115 channel->ch_bd->bd_ops->assert_modem_signals(channel); 116 117 jsm_printk(IOCTL, INFO, &channel->ch_bd->pci_dev, "finish\n"); 118 udelay(10); 119} 120 121static void jsm_tty_start_tx(struct uart_port *port) 122{ 123 struct jsm_channel *channel = (struct jsm_channel *)port; 124 125 jsm_printk(IOCTL, INFO, &channel->ch_bd->pci_dev, "start\n"); 126 127 channel->ch_flags &= ~(CH_STOP); 128 jsm_tty_write(port); 129 130 jsm_printk(IOCTL, INFO, &channel->ch_bd->pci_dev, "finish\n"); 131} 132 133static void jsm_tty_stop_tx(struct uart_port *port) 134{ 135 struct jsm_channel *channel = (struct jsm_channel *)port; 136 137 jsm_printk(IOCTL, INFO, &channel->ch_bd->pci_dev, "start\n"); 138 139 channel->ch_flags |= (CH_STOP); 140 141 jsm_printk(IOCTL, INFO, &channel->ch_bd->pci_dev, "finish\n"); 142} 143 144static void jsm_tty_send_xchar(struct uart_port *port, char ch) 145{ 146 unsigned long lock_flags; 147 struct jsm_channel *channel = (struct jsm_channel *)port; 148 struct ktermios *termios; 149 150 spin_lock_irqsave(&port->lock, lock_flags); 151 termios = port->state->port.tty->termios; 152 if (ch == termios->c_cc[VSTART]) 153 channel->ch_bd->bd_ops->send_start_character(channel); 154 155 if (ch == termios->c_cc[VSTOP]) 156 channel->ch_bd->bd_ops->send_stop_character(channel); 157 spin_unlock_irqrestore(&port->lock, lock_flags); 158} 159 160static void jsm_tty_stop_rx(struct uart_port *port) 161{ 162 struct jsm_channel *channel = (struct jsm_channel *)port; 163 164 channel->ch_bd->bd_ops->disable_receiver(channel); 165} 166 167static void jsm_tty_enable_ms(struct uart_port *port) 168{ 169 /* Nothing needed */ 170} 171 172static void jsm_tty_break(struct uart_port *port, int break_state) 173{ 174 unsigned long lock_flags; 175 struct jsm_channel *channel = (struct jsm_channel *)port; 176 177 spin_lock_irqsave(&port->lock, lock_flags); 178 if (break_state == -1) 179 channel->ch_bd->bd_ops->send_break(channel); 180 else 181 channel->ch_bd->bd_ops->clear_break(channel, 0); 182 183 spin_unlock_irqrestore(&port->lock, lock_flags); 184} 185 186static int jsm_tty_open(struct uart_port *port) 187{ 188 struct jsm_board *brd; 189 struct jsm_channel *channel = (struct jsm_channel *)port; 190 struct ktermios *termios; 191 192 /* Get board pointer from our array of majors we have allocated */ 193 brd = channel->ch_bd; 194 195 /* 196 * Allocate channel buffers for read/write/error. 197 * Set flag, so we don't get trounced on. 198 */ 199 channel->ch_flags |= (CH_OPENING); 200 201 /* Drop locks, as malloc with GFP_KERNEL can sleep */ 202 203 if (!channel->ch_rqueue) { 204 channel->ch_rqueue = kzalloc(RQUEUESIZE, GFP_KERNEL); 205 if (!channel->ch_rqueue) { 206 jsm_printk(INIT, ERR, &channel->ch_bd->pci_dev, 207 "unable to allocate read queue buf"); 208 return -ENOMEM; 209 } 210 } 211 if (!channel->ch_equeue) { 212 channel->ch_equeue = kzalloc(EQUEUESIZE, GFP_KERNEL); 213 if (!channel->ch_equeue) { 214 jsm_printk(INIT, ERR, &channel->ch_bd->pci_dev, 215 "unable to allocate error queue buf"); 216 return -ENOMEM; 217 } 218 } 219 if (!channel->ch_wqueue) { 220 channel->ch_wqueue = kzalloc(WQUEUESIZE, GFP_KERNEL); 221 if (!channel->ch_wqueue) { 222 jsm_printk(INIT, ERR, &channel->ch_bd->pci_dev, 223 "unable to allocate write queue buf"); 224 return -ENOMEM; 225 } 226 } 227 228 channel->ch_flags &= ~(CH_OPENING); 229 /* 230 * Initialize if neither terminal is open. 231 */ 232 jsm_printk(OPEN, INFO, &channel->ch_bd->pci_dev, 233 "jsm_open: initializing channel in open...\n"); 234 235 /* 236 * Flush input queues. 237 */ 238 channel->ch_r_head = channel->ch_r_tail = 0; 239 channel->ch_e_head = channel->ch_e_tail = 0; 240 channel->ch_w_head = channel->ch_w_tail = 0; 241 242 brd->bd_ops->flush_uart_write(channel); 243 brd->bd_ops->flush_uart_read(channel); 244 245 channel->ch_flags = 0; 246 channel->ch_cached_lsr = 0; 247 channel->ch_stops_sent = 0; 248 249 termios = port->state->port.tty->termios; 250 channel->ch_c_cflag = termios->c_cflag; 251 channel->ch_c_iflag = termios->c_iflag; 252 channel->ch_c_oflag = termios->c_oflag; 253 channel->ch_c_lflag = termios->c_lflag; 254 channel->ch_startc = termios->c_cc[VSTART]; 255 channel->ch_stopc = termios->c_cc[VSTOP]; 256 257 /* Tell UART to init itself */ 258 brd->bd_ops->uart_init(channel); 259 260 /* 261 * Run param in case we changed anything 262 */ 263 brd->bd_ops->param(channel); 264 265 jsm_carrier(channel); 266 267 channel->ch_open_count++; 268 269 jsm_printk(OPEN, INFO, &channel->ch_bd->pci_dev, "finish\n"); 270 return 0; 271} 272 273static void jsm_tty_close(struct uart_port *port) 274{ 275 struct jsm_board *bd; 276 struct ktermios *ts; 277 struct jsm_channel *channel = (struct jsm_channel *)port; 278 279 jsm_printk(CLOSE, INFO, &channel->ch_bd->pci_dev, "start\n"); 280 281 bd = channel->ch_bd; 282 ts = port->state->port.tty->termios; 283 284 channel->ch_flags &= ~(CH_STOPI); 285 286 channel->ch_open_count--; 287 288 /* 289 * If we have HUPCL set, lower DTR and RTS 290 */ 291 if (channel->ch_c_cflag & HUPCL) { 292 jsm_printk(CLOSE, INFO, &channel->ch_bd->pci_dev, 293 "Close. HUPCL set, dropping DTR/RTS\n"); 294 295 /* Drop RTS/DTR */ 296 channel->ch_mostat &= ~(UART_MCR_DTR | UART_MCR_RTS); 297 bd->bd_ops->assert_modem_signals(channel); 298 } 299 300 /* Turn off UART interrupts for this port */ 301 channel->ch_bd->bd_ops->uart_off(channel); 302 303 jsm_printk(CLOSE, INFO, &channel->ch_bd->pci_dev, "finish\n"); 304} 305 306static void jsm_tty_set_termios(struct uart_port *port, 307 struct ktermios *termios, 308 struct ktermios *old_termios) 309{ 310 unsigned long lock_flags; 311 struct jsm_channel *channel = (struct jsm_channel *)port; 312 313 spin_lock_irqsave(&port->lock, lock_flags); 314 channel->ch_c_cflag = termios->c_cflag; 315 channel->ch_c_iflag = termios->c_iflag; 316 channel->ch_c_oflag = termios->c_oflag; 317 channel->ch_c_lflag = termios->c_lflag; 318 channel->ch_startc = termios->c_cc[VSTART]; 319 channel->ch_stopc = termios->c_cc[VSTOP]; 320 321 channel->ch_bd->bd_ops->param(channel); 322 jsm_carrier(channel); 323 spin_unlock_irqrestore(&port->lock, lock_flags); 324} 325 326static const char *jsm_tty_type(struct uart_port *port) 327{ 328 return "jsm"; 329} 330 331static void jsm_tty_release_port(struct uart_port *port) 332{ 333} 334 335static int jsm_tty_request_port(struct uart_port *port) 336{ 337 return 0; 338} 339 340static void jsm_config_port(struct uart_port *port, int flags) 341{ 342 port->type = PORT_JSM; 343} 344 345static struct uart_ops jsm_ops = { 346 .tx_empty = jsm_tty_tx_empty, 347 .set_mctrl = jsm_tty_set_mctrl, 348 .get_mctrl = jsm_tty_get_mctrl, 349 .stop_tx = jsm_tty_stop_tx, 350 .start_tx = jsm_tty_start_tx, 351 .send_xchar = jsm_tty_send_xchar, 352 .stop_rx = jsm_tty_stop_rx, 353 .enable_ms = jsm_tty_enable_ms, 354 .break_ctl = jsm_tty_break, 355 .startup = jsm_tty_open, 356 .shutdown = jsm_tty_close, 357 .set_termios = jsm_tty_set_termios, 358 .type = jsm_tty_type, 359 .release_port = jsm_tty_release_port, 360 .request_port = jsm_tty_request_port, 361 .config_port = jsm_config_port, 362}; 363 364/* 365 * jsm_tty_init() 366 * 367 * Init the tty subsystem. Called once per board after board has been 368 * downloaded and init'ed. 369 */ 370int __devinit jsm_tty_init(struct jsm_board *brd) 371{ 372 int i; 373 void __iomem *vaddr; 374 struct jsm_channel *ch; 375 376 if (!brd) 377 return -ENXIO; 378 379 jsm_printk(INIT, INFO, &brd->pci_dev, "start\n"); 380 381 /* 382 * Initialize board structure elements. 383 */ 384 385 brd->nasync = brd->maxports; 386 387 /* 388 * Allocate channel memory that might not have been allocated 389 * when the driver was first loaded. 390 */ 391 for (i = 0; i < brd->nasync; i++) { 392 if (!brd->channels[i]) { 393 394 /* 395 * Okay to malloc with GFP_KERNEL, we are not at 396 * interrupt context, and there are no locks held. 397 */ 398 brd->channels[i] = kzalloc(sizeof(struct jsm_channel), GFP_KERNEL); 399 if (!brd->channels[i]) { 400 jsm_printk(CORE, ERR, &brd->pci_dev, 401 "%s:%d Unable to allocate memory for channel struct\n", 402 __FILE__, __LINE__); 403 } 404 } 405 } 406 407 ch = brd->channels[0]; 408 vaddr = brd->re_map_membase; 409 410 /* Set up channel variables */ 411 for (i = 0; i < brd->nasync; i++, ch = brd->channels[i]) { 412 413 if (!brd->channels[i]) 414 continue; 415 416 spin_lock_init(&ch->ch_lock); 417 418 if (brd->bd_uart_offset == 0x200) 419 ch->ch_neo_uart = vaddr + (brd->bd_uart_offset * i); 420 421 ch->ch_bd = brd; 422 ch->ch_portnum = i; 423 424 /* .25 second delay */ 425 ch->ch_close_delay = 250; 426 427 init_waitqueue_head(&ch->ch_flags_wait); 428 } 429 430 jsm_printk(INIT, INFO, &brd->pci_dev, "finish\n"); 431 return 0; 432} 433 434int jsm_uart_port_init(struct jsm_board *brd) 435{ 436 int i, rc; 437 unsigned int line; 438 struct jsm_channel *ch; 439 440 if (!brd) 441 return -ENXIO; 442 443 jsm_printk(INIT, INFO, &brd->pci_dev, "start\n"); 444 445 /* 446 * Initialize board structure elements. 447 */ 448 449 brd->nasync = brd->maxports; 450 451 /* Set up channel variables */ 452 for (i = 0; i < brd->nasync; i++, ch = brd->channels[i]) { 453 454 if (!brd->channels[i]) 455 continue; 456 457 brd->channels[i]->uart_port.irq = brd->irq; 458 brd->channels[i]->uart_port.uartclk = 14745600; 459 brd->channels[i]->uart_port.type = PORT_JSM; 460 brd->channels[i]->uart_port.iotype = UPIO_MEM; 461 brd->channels[i]->uart_port.membase = brd->re_map_membase; 462 brd->channels[i]->uart_port.fifosize = 16; 463 brd->channels[i]->uart_port.ops = &jsm_ops; 464 line = find_first_zero_bit(linemap, MAXLINES); 465 if (line >= MAXLINES) { 466 printk(KERN_INFO "jsm: linemap is full, added device failed\n"); 467 continue; 468 } else 469 set_bit(line, linemap); 470 brd->channels[i]->uart_port.line = line; 471 rc = uart_add_one_port (&jsm_uart_driver, &brd->channels[i]->uart_port); 472 if (rc){ 473 printk(KERN_INFO "jsm: Port %d failed. Aborting...\n", i); 474 return rc; 475 } 476 else 477 printk(KERN_INFO "jsm: Port %d added\n", i); 478 } 479 480 jsm_printk(INIT, INFO, &brd->pci_dev, "finish\n"); 481 return 0; 482} 483 484int jsm_remove_uart_port(struct jsm_board *brd) 485{ 486 int i; 487 struct jsm_channel *ch; 488 489 if (!brd) 490 return -ENXIO; 491 492 jsm_printk(INIT, INFO, &brd->pci_dev, "start\n"); 493 494 /* 495 * Initialize board structure elements. 496 */ 497 498 brd->nasync = brd->maxports; 499 500 /* Set up channel variables */ 501 for (i = 0; i < brd->nasync; i++) { 502 503 if (!brd->channels[i]) 504 continue; 505 506 ch = brd->channels[i]; 507 508 clear_bit(ch->uart_port.line, linemap); 509 uart_remove_one_port(&jsm_uart_driver, &brd->channels[i]->uart_port); 510 } 511 512 jsm_printk(INIT, INFO, &brd->pci_dev, "finish\n"); 513 return 0; 514} 515 516void jsm_input(struct jsm_channel *ch) 517{ 518 struct jsm_board *bd; 519 struct tty_struct *tp; 520 u32 rmask; 521 u16 head; 522 u16 tail; 523 int data_len; 524 unsigned long lock_flags; 525 int len = 0; 526 int n = 0; 527 int s = 0; 528 int i = 0; 529 530 jsm_printk(READ, INFO, &ch->ch_bd->pci_dev, "start\n"); 531 532 if (!ch) 533 return; 534 535 tp = ch->uart_port.state->port.tty; 536 537 bd = ch->ch_bd; 538 if(!bd) 539 return; 540 541 spin_lock_irqsave(&ch->ch_lock, lock_flags); 542 543 /* 544 *Figure the number of characters in the buffer. 545 *Exit immediately if none. 546 */ 547 548 rmask = RQUEUEMASK; 549 550 head = ch->ch_r_head & rmask; 551 tail = ch->ch_r_tail & rmask; 552 553 data_len = (head - tail) & rmask; 554 if (data_len == 0) { 555 spin_unlock_irqrestore(&ch->ch_lock, lock_flags); 556 return; 557 } 558 559 jsm_printk(READ, INFO, &ch->ch_bd->pci_dev, "start\n"); 560 561 /* 562 *If the device is not open, or CREAD is off, flush 563 *input data and return immediately. 564 */ 565 if (!tp || 566 !(tp->termios->c_cflag & CREAD) ) { 567 568 jsm_printk(READ, INFO, &ch->ch_bd->pci_dev, 569 "input. dropping %d bytes on port %d...\n", data_len, ch->ch_portnum); 570 ch->ch_r_head = tail; 571 572 /* Force queue flow control to be released, if needed */ 573 jsm_check_queue_flow_control(ch); 574 575 spin_unlock_irqrestore(&ch->ch_lock, lock_flags); 576 return; 577 } 578 579 /* 580 * If we are throttled, simply don't read any data. 581 */ 582 if (ch->ch_flags & CH_STOPI) { 583 spin_unlock_irqrestore(&ch->ch_lock, lock_flags); 584 jsm_printk(READ, INFO, &ch->ch_bd->pci_dev, 585 "Port %d throttled, not reading any data. head: %x tail: %x\n", 586 ch->ch_portnum, head, tail); 587 return; 588 } 589 590 jsm_printk(READ, INFO, &ch->ch_bd->pci_dev, "start 2\n"); 591 592 if (data_len <= 0) { 593 spin_unlock_irqrestore(&ch->ch_lock, lock_flags); 594 jsm_printk(READ, INFO, &ch->ch_bd->pci_dev, "jsm_input 1\n"); 595 return; 596 } 597 598 len = tty_buffer_request_room(tp, data_len); 599 n = len; 600 601 /* 602 * n now contains the most amount of data we can copy, 603 * bounded either by the flip buffer size or the amount 604 * of data the card actually has pending... 605 */ 606 while (n) { 607 s = ((head >= tail) ? head : RQUEUESIZE) - tail; 608 s = min(s, n); 609 610 if (s <= 0) 611 break; 612 613 /* 614 * If conditions are such that ld needs to see all 615 * UART errors, we will have to walk each character 616 * and error byte and send them to the buffer one at 617 * a time. 618 */ 619 620 if (I_PARMRK(tp) || I_BRKINT(tp) || I_INPCK(tp)) { 621 for (i = 0; i < s; i++) { 622 /* 623 * Give the Linux ld the flags in the 624 * format it likes. 625 */ 626 if (*(ch->ch_equeue +tail +i) & UART_LSR_BI) 627 tty_insert_flip_char(tp, *(ch->ch_rqueue +tail +i), TTY_BREAK); 628 else if (*(ch->ch_equeue +tail +i) & UART_LSR_PE) 629 tty_insert_flip_char(tp, *(ch->ch_rqueue +tail +i), TTY_PARITY); 630 else if (*(ch->ch_equeue +tail +i) & UART_LSR_FE) 631 tty_insert_flip_char(tp, *(ch->ch_rqueue +tail +i), TTY_FRAME); 632 else 633 tty_insert_flip_char(tp, *(ch->ch_rqueue +tail +i), TTY_NORMAL); 634 } 635 } else { 636 tty_insert_flip_string(tp, ch->ch_rqueue + tail, s) ; 637 } 638 tail += s; 639 n -= s; 640 /* Flip queue if needed */ 641 tail &= rmask; 642 } 643 644 ch->ch_r_tail = tail & rmask; 645 ch->ch_e_tail = tail & rmask; 646 jsm_check_queue_flow_control(ch); 647 spin_unlock_irqrestore(&ch->ch_lock, lock_flags); 648 649 /* Tell the tty layer its okay to "eat" the data now */ 650 tty_flip_buffer_push(tp); 651 652 jsm_printk(IOCTL, INFO, &ch->ch_bd->pci_dev, "finish\n"); 653} 654 655static void jsm_carrier(struct jsm_channel *ch) 656{ 657 struct jsm_board *bd; 658 659 int virt_carrier = 0; 660 int phys_carrier = 0; 661 662 jsm_printk(CARR, INFO, &ch->ch_bd->pci_dev, "start\n"); 663 if (!ch) 664 return; 665 666 bd = ch->ch_bd; 667 668 if (!bd) 669 return; 670 671 if (ch->ch_mistat & UART_MSR_DCD) { 672 jsm_printk(CARR, INFO, &ch->ch_bd->pci_dev, 673 "mistat: %x D_CD: %x\n", ch->ch_mistat, ch->ch_mistat & UART_MSR_DCD); 674 phys_carrier = 1; 675 } 676 677 if (ch->ch_c_cflag & CLOCAL) 678 virt_carrier = 1; 679 680 jsm_printk(CARR, INFO, &ch->ch_bd->pci_dev, 681 "DCD: physical: %d virt: %d\n", phys_carrier, virt_carrier); 682 683 /* 684 * Test for a VIRTUAL carrier transition to HIGH. 685 */ 686 if (((ch->ch_flags & CH_FCAR) == 0) && (virt_carrier == 1)) { 687 688 /* 689 * When carrier rises, wake any threads waiting 690 * for carrier in the open routine. 691 */ 692 693 jsm_printk(CARR, INFO, &ch->ch_bd->pci_dev, 694 "carrier: virt DCD rose\n"); 695 696 if (waitqueue_active(&(ch->ch_flags_wait))) 697 wake_up_interruptible(&ch->ch_flags_wait); 698 } 699 700 /* 701 * Test for a PHYSICAL carrier transition to HIGH. 702 */ 703 if (((ch->ch_flags & CH_CD) == 0) && (phys_carrier == 1)) { 704 705 /* 706 * When carrier rises, wake any threads waiting 707 * for carrier in the open routine. 708 */ 709 710 jsm_printk(CARR, INFO, &ch->ch_bd->pci_dev, 711 "carrier: physical DCD rose\n"); 712 713 if (waitqueue_active(&(ch->ch_flags_wait))) 714 wake_up_interruptible(&ch->ch_flags_wait); 715 } 716 717 /* 718 * Test for a PHYSICAL transition to low, so long as we aren't 719 * currently ignoring physical transitions (which is what "virtual 720 * carrier" indicates). 721 * 722 * The transition of the virtual carrier to low really doesn't 723 * matter... it really only means "ignore carrier state", not 724 * "make pretend that carrier is there". 725 */ 726 if ((virt_carrier == 0) && ((ch->ch_flags & CH_CD) != 0) 727 && (phys_carrier == 0)) { 728 /* 729 * When carrier drops: 730 * 731 * Drop carrier on all open units. 732 * 733 * Flush queues, waking up any task waiting in the 734 * line discipline. 735 * 736 * Send a hangup to the control terminal. 737 * 738 * Enable all select calls. 739 */ 740 if (waitqueue_active(&(ch->ch_flags_wait))) 741 wake_up_interruptible(&ch->ch_flags_wait); 742 } 743 744 /* 745 * Make sure that our cached values reflect the current reality. 746 */ 747 if (virt_carrier == 1) 748 ch->ch_flags |= CH_FCAR; 749 else 750 ch->ch_flags &= ~CH_FCAR; 751 752 if (phys_carrier == 1) 753 ch->ch_flags |= CH_CD; 754 else 755 ch->ch_flags &= ~CH_CD; 756} 757 758 759void jsm_check_queue_flow_control(struct jsm_channel *ch) 760{ 761 struct board_ops *bd_ops = ch->ch_bd->bd_ops; 762 int qleft; 763 764 /* Store how much space we have left in the queue */ 765 if ((qleft = ch->ch_r_tail - ch->ch_r_head - 1) < 0) 766 qleft += RQUEUEMASK + 1; 767 768 /* 769 * Check to see if we should enforce flow control on our queue because 770 * the ld (or user) isn't reading data out of our queue fast enuf. 771 * 772 * NOTE: This is done based on what the current flow control of the 773 * port is set for. 774 * 775 * 1) HWFLOW (RTS) - Turn off the UART's Receive interrupt. 776 * This will cause the UART's FIFO to back up, and force 777 * the RTS signal to be dropped. 778 * 2) SWFLOW (IXOFF) - Keep trying to send a stop character to 779 * the other side, in hopes it will stop sending data to us. 780 * 3) NONE - Nothing we can do. We will simply drop any extra data 781 * that gets sent into us when the queue fills up. 782 */ 783 if (qleft < 256) { 784 /* HWFLOW */ 785 if (ch->ch_c_cflag & CRTSCTS) { 786 if(!(ch->ch_flags & CH_RECEIVER_OFF)) { 787 bd_ops->disable_receiver(ch); 788 ch->ch_flags |= (CH_RECEIVER_OFF); 789 jsm_printk(READ, INFO, &ch->ch_bd->pci_dev, 790 "Internal queue hit hilevel mark (%d)! Turning off interrupts.\n", 791 qleft); 792 } 793 } 794 /* SWFLOW */ 795 else if (ch->ch_c_iflag & IXOFF) { 796 if (ch->ch_stops_sent <= MAX_STOPS_SENT) { 797 bd_ops->send_stop_character(ch); 798 ch->ch_stops_sent++; 799 jsm_printk(READ, INFO, &ch->ch_bd->pci_dev, 800 "Sending stop char! Times sent: %x\n", ch->ch_stops_sent); 801 } 802 } 803 } 804 805 /* 806 * Check to see if we should unenforce flow control because 807 * ld (or user) finally read enuf data out of our queue. 808 * 809 * NOTE: This is done based on what the current flow control of the 810 * port is set for. 811 * 812 * 1) HWFLOW (RTS) - Turn back on the UART's Receive interrupt. 813 * This will cause the UART's FIFO to raise RTS back up, 814 * which will allow the other side to start sending data again. 815 * 2) SWFLOW (IXOFF) - Send a start character to 816 * the other side, so it will start sending data to us again. 817 * 3) NONE - Do nothing. Since we didn't do anything to turn off the 818 * other side, we don't need to do anything now. 819 */ 820 if (qleft > (RQUEUESIZE / 2)) { 821 /* HWFLOW */ 822 if (ch->ch_c_cflag & CRTSCTS) { 823 if (ch->ch_flags & CH_RECEIVER_OFF) { 824 bd_ops->enable_receiver(ch); 825 ch->ch_flags &= ~(CH_RECEIVER_OFF); 826 jsm_printk(READ, INFO, &ch->ch_bd->pci_dev, 827 "Internal queue hit lowlevel mark (%d)! Turning on interrupts.\n", 828 qleft); 829 } 830 } 831 /* SWFLOW */ 832 else if (ch->ch_c_iflag & IXOFF && ch->ch_stops_sent) { 833 ch->ch_stops_sent = 0; 834 bd_ops->send_start_character(ch); 835 jsm_printk(READ, INFO, &ch->ch_bd->pci_dev, "Sending start char!\n"); 836 } 837 } 838} 839 840/* 841 * jsm_tty_write() 842 * 843 * Take data from the user or kernel and send it out to the FEP. 844 * In here exists all the Transparent Print magic as well. 845 */ 846int jsm_tty_write(struct uart_port *port) 847{ 848 int bufcount; 849 int data_count = 0,data_count1 =0; 850 u16 head; 851 u16 tail; 852 u16 tmask; 853 u32 remain; 854 int temp_tail = port->state->xmit.tail; 855 struct jsm_channel *channel = (struct jsm_channel *)port; 856 857 tmask = WQUEUEMASK; 858 head = (channel->ch_w_head) & tmask; 859 tail = (channel->ch_w_tail) & tmask; 860 861 if ((bufcount = tail - head - 1) < 0) 862 bufcount += WQUEUESIZE; 863 864 bufcount = min(bufcount, 56); 865 remain = WQUEUESIZE - head; 866 867 data_count = 0; 868 if (bufcount >= remain) { 869 bufcount -= remain; 870 while ((port->state->xmit.head != temp_tail) && 871 (data_count < remain)) { 872 channel->ch_wqueue[head++] = 873 port->state->xmit.buf[temp_tail]; 874 875 temp_tail++; 876 temp_tail &= (UART_XMIT_SIZE - 1); 877 data_count++; 878 } 879 if (data_count == remain) head = 0; 880 } 881 882 data_count1 = 0; 883 if (bufcount > 0) { 884 remain = bufcount; 885 while ((port->state->xmit.head != temp_tail) && 886 (data_count1 < remain)) { 887 channel->ch_wqueue[head++] = 888 port->state->xmit.buf[temp_tail]; 889 890 temp_tail++; 891 temp_tail &= (UART_XMIT_SIZE - 1); 892 data_count1++; 893 894 } 895 } 896 897 port->state->xmit.tail = temp_tail; 898 899 data_count += data_count1; 900 if (data_count) { 901 head &= tmask; 902 channel->ch_w_head = head; 903 } 904 905 if (data_count) { 906 channel->ch_bd->bd_ops->copy_data_from_queue_to_uart(channel); 907 } 908 909 return data_count; 910} 911