drivers/serial/jsm/jsm_tty.c

   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  * Wendy Xiong   <wendyx@us.ltcfwd.linux.ibm.com>
  24  *
  25  ***********************************************************************/
  26 #include <linux/tty.h>
  27 #include <linux/tty_flip.h>
  28 #include <linux/serial_reg.h>
  29 #include <linux/delay.h>        /* For udelay */
  30 #include <linux/pci.h>
  31
  32 #include "jsm.h"
  33
  34 static inline int jsm_get_mstat(struct jsm_channel *ch)
  35 {
  36         unsigned char mstat;
  37         unsigned result;
  38
  39         jsm_printk(IOCTL, INFO, &ch->ch_bd->pci_dev, "start\n");
  40
  41         mstat = (ch->ch_mostat | ch->ch_mistat);
  42
  43         result = 0;
  44
  45         if (mstat & UART_MCR_DTR)
  46                 result |= TIOCM_DTR;
  47         if (mstat & UART_MCR_RTS)
  48                 result |= TIOCM_RTS;
  49         if (mstat & UART_MSR_CTS)
  50                 result |= TIOCM_CTS;
  51         if (mstat & UART_MSR_DSR)
  52                 result |= TIOCM_DSR;
  53         if (mstat & UART_MSR_RI)
  54                 result |= TIOCM_RI;
  55         if (mstat & UART_MSR_DCD)
  56                 result |= TIOCM_CD;
  57
  58         jsm_printk(IOCTL, INFO, &ch->ch_bd->pci_dev, "finish\n");
  59         return result;
  60 }
  61
  62 static unsigned int jsm_tty_tx_empty(struct uart_port *port)
  63 {
  64         return TIOCSER_TEMT;
  65 }
  66
  67 /*
  68  * Return modem signals to ld.
  69  */
  70 static unsigned int jsm_tty_get_mctrl(struct uart_port *port)
  71 {
  72         int result;
  73         struct jsm_channel *channel = (struct jsm_channel *)port;
  74
  75         jsm_printk(IOCTL, INFO, &channel->ch_bd->pci_dev, "start\n");
  76
  77         result = jsm_get_mstat(channel);
  78
  79         if (result < 0)
  80                 return -ENXIO;
  81
  82         jsm_printk(IOCTL, INFO, &channel->ch_bd->pci_dev, "finish\n");
  83
  84         return result;
  85 }
  86
  87 /*
  88  * jsm_set_modem_info()
  89  *
  90  * Set modem signals, called by ld.
  91  */
  92 static void jsm_tty_set_mctrl(struct uart_port *port, unsigned int mctrl)
  93 {
  94         struct jsm_channel *channel = (struct jsm_channel *)port;
  95
  96         jsm_printk(IOCTL, INFO, &channel->ch_bd->pci_dev, "start\n");
  97
  98         if (mctrl & TIOCM_RTS)
  99                 channel->ch_mostat |= UART_MCR_RTS;
 100         else
 101                 channel->ch_mostat &= ~UART_MCR_RTS;
 102
 103         if (mctrl & TIOCM_DTR)
 104                 channel->ch_mostat |= UART_MCR_DTR;
 105         else
 106                 channel->ch_mostat &= ~UART_MCR_DTR;
 107
 108         channel->ch_bd->bd_ops->assert_modem_signals(channel);
 109
 110         jsm_printk(IOCTL, INFO, &channel->ch_bd->pci_dev, "finish\n");
 111         udelay(10);
 112 }
 113
 114 static void jsm_tty_start_tx(struct uart_port *port, unsigned int tty_start)
 115 {
 116         struct jsm_channel *channel = (struct jsm_channel *)port;
 117
 118         jsm_printk(IOCTL, INFO, &channel->ch_bd->pci_dev, "start\n");
 119
 120         channel->ch_flags &= ~(CH_STOP);
 121         jsm_tty_write(port);
 122
 123         jsm_printk(IOCTL, INFO, &channel->ch_bd->pci_dev, "finish\n");
 124 }
 125
 126 static void jsm_tty_stop_tx(struct uart_port *port, unsigned int tty_stop)
 127 {
 128         struct jsm_channel *channel = (struct jsm_channel *)port;
 129
 130         jsm_printk(IOCTL, INFO, &channel->ch_bd->pci_dev, "start\n");
 131
 132         channel->ch_flags |= (CH_STOP);
 133
 134         jsm_printk(IOCTL, INFO, &channel->ch_bd->pci_dev, "finish\n");
 135 }
 136
 137 static void jsm_tty_send_xchar(struct uart_port *port, char ch)
 138 {
 139         unsigned long lock_flags;
 140         struct jsm_channel *channel = (struct jsm_channel *)port;
 141
 142         spin_lock_irqsave(&port->lock, lock_flags);
 143         if (ch == port->info->tty->termios->c_cc[VSTART])
 144                 channel->ch_bd->bd_ops->send_start_character(channel);
 145
 146         if (ch == port->info->tty->termios->c_cc[VSTOP])
 147                 channel->ch_bd->bd_ops->send_stop_character(channel);
 148         spin_unlock_irqrestore(&port->lock, lock_flags);
 149 }
 150
 151 static void jsm_tty_stop_rx(struct uart_port *port)
 152 {
 153         struct jsm_channel *channel = (struct jsm_channel *)port;
 154
 155         channel->ch_bd->bd_ops->disable_receiver(channel);
 156 }
 157
 158 static void jsm_tty_break(struct uart_port *port, int break_state)
 159 {
 160         unsigned long lock_flags;
 161         struct jsm_channel *channel = (struct jsm_channel *)port;
 162
 163         spin_lock_irqsave(&port->lock, lock_flags);
 164         if (break_state == -1)
 165                 channel->ch_bd->bd_ops->send_break(channel);
 166         else
 167                 channel->ch_bd->bd_ops->clear_break(channel, 0);
 168
 169         spin_unlock_irqrestore(&port->lock, lock_flags);
 170 }
 171
 172 static int jsm_tty_open(struct uart_port *port)
 173 {
 174         struct jsm_board *brd;
 175         int rc = 0;
 176         struct jsm_channel *channel = (struct jsm_channel *)port;
 177
 178         /* Get board pointer from our array of majors we have allocated */
 179         brd = channel->ch_bd;
 180
 181         /*
 182          * Allocate channel buffers for read/write/error.
 183          * Set flag, so we don't get trounced on.
 184          */
 185         channel->ch_flags |= (CH_OPENING);
 186
 187         /* Drop locks, as malloc with GFP_KERNEL can sleep */
 188
 189         if (!channel->ch_rqueue) {
 190                 channel->ch_rqueue = (u8 *) kmalloc(RQUEUESIZE, GFP_KERNEL);
 191                 if (!channel->ch_rqueue) {
 192                         jsm_printk(INIT, ERR, &channel->ch_bd->pci_dev,
 193                                 "unable to allocate read queue buf");
 194                         return -ENOMEM;
 195                 }
 196                 memset(channel->ch_rqueue, 0, RQUEUESIZE);
 197         }
 198         if (!channel->ch_equeue) {
 199                 channel->ch_equeue = (u8 *) kmalloc(EQUEUESIZE, GFP_KERNEL);
 200                 if (!channel->ch_equeue) {
 201                         jsm_printk(INIT, ERR, &channel->ch_bd->pci_dev,
 202                                 "unable to allocate error queue buf");
 203                         return -ENOMEM;
 204                 }
 205                 memset(channel->ch_equeue, 0, EQUEUESIZE);
 206         }
 207         if (!channel->ch_wqueue) {
 208                 channel->ch_wqueue = (u8 *) kmalloc(WQUEUESIZE, GFP_KERNEL);
 209                 if (!channel->ch_wqueue) {
 210                         jsm_printk(INIT, ERR, &channel->ch_bd->pci_dev,
 211                                 "unable to allocate write queue buf");
 212                         return -ENOMEM;
 213                 }
 214                 memset(channel->ch_wqueue, 0, WQUEUESIZE);
 215         }
 216
 217         channel->ch_flags &= ~(CH_OPENING);
 218         /*
 219          * Initialize if neither terminal is open.
 220          */
 221         jsm_printk(OPEN, INFO, &channel->ch_bd->pci_dev,
 222                 "jsm_open: initializing channel in open...\n");
 223
 224         /*
 225          * Flush input queues.
 226          */
 227         channel->ch_r_head = channel->ch_r_tail = 0;
 228         channel->ch_e_head = channel->ch_e_tail = 0;
 229         channel->ch_w_head = channel->ch_w_tail = 0;
 230
 231         brd->bd_ops->flush_uart_write(channel);
 232         brd->bd_ops->flush_uart_read(channel);
 233
 234         channel->ch_flags = 0;
 235         channel->ch_cached_lsr = 0;
 236         channel->ch_stops_sent = 0;
 237
 238         channel->ch_c_cflag     = port->info->tty->termios->c_cflag;
 239         channel->ch_c_iflag     = port->info->tty->termios->c_iflag;
 240         channel->ch_c_oflag     = port->info->tty->termios->c_oflag;
 241         channel->ch_c_lflag     = port->info->tty->termios->c_lflag;
 242         channel->ch_startc = port->info->tty->termios->c_cc[VSTART];
 243         channel->ch_stopc = port->info->tty->termios->c_cc[VSTOP];
 244
 245         /* Tell UART to init itself */
 246         brd->bd_ops->uart_init(channel);
 247
 248         /*
 249          * Run param in case we changed anything
 250          */
 251         brd->bd_ops->param(channel);
 252
 253         jsm_carrier(channel);
 254
 255         channel->ch_open_count++;
 256
 257         jsm_printk(OPEN, INFO, &channel->ch_bd->pci_dev, "finish\n");
 258         return rc;
 259 }
 260
 261 static void jsm_tty_close(struct uart_port *port)
 262 {
 263         struct jsm_board *bd;
 264         struct termios *ts;
 265         struct jsm_channel *channel = (struct jsm_channel *)port;
 266
 267         jsm_printk(CLOSE, INFO, &channel->ch_bd->pci_dev, "start\n");
 268
 269         bd = channel->ch_bd;
 270         ts = channel->uart_port.info->tty->termios;
 271
 272         channel->ch_flags &= ~(CH_STOPI);
 273
 274         channel->ch_open_count--;
 275
 276         /*
 277          * If we have HUPCL set, lower DTR and RTS
 278          */
 279         if (channel->ch_c_cflag & HUPCL) {
 280                 jsm_printk(CLOSE, INFO, &channel->ch_bd->pci_dev,
 281                         "Close. HUPCL set, dropping DTR/RTS\n");
 282
 283                 /* Drop RTS/DTR */
 284                 channel->ch_mostat &= ~(UART_MCR_DTR | UART_MCR_RTS);
 285                 bd->bd_ops->assert_modem_signals(channel);
 286         }
 287
 288         channel->ch_old_baud = 0;
 289
 290         /* Turn off UART interrupts for this port */
 291         channel->ch_bd->bd_ops->uart_off(channel);
 292
 293         jsm_printk(CLOSE, INFO, &channel->ch_bd->pci_dev, "finish\n");
 294 }
 295
 296 static void jsm_tty_set_termios(struct uart_port *port,
 297                                  struct termios *termios,
 298                                  struct termios *old_termios)
 299 {
 300         unsigned long lock_flags;
 301         struct jsm_channel *channel = (struct jsm_channel *)port;
 302
 303         spin_lock_irqsave(&port->lock, lock_flags);
 304         channel->ch_c_cflag     = termios->c_cflag;
 305         channel->ch_c_iflag     = termios->c_iflag;
 306         channel->ch_c_oflag     = termios->c_oflag;
 307         channel->ch_c_lflag     = termios->c_lflag;
 308         channel->ch_startc      = termios->c_cc[VSTART];
 309         channel->ch_stopc       = termios->c_cc[VSTOP];
 310
 311         channel->ch_bd->bd_ops->param(channel);
 312         jsm_carrier(channel);
 313         spin_unlock_irqrestore(&port->lock, lock_flags);
 314 }
 315
 316 static const char *jsm_tty_type(struct uart_port *port)
 317 {
 318         return "jsm";
 319 }
 320
 321 static void jsm_tty_release_port(struct uart_port *port)
 322 {
 323 }
 324
 325 static int jsm_tty_request_port(struct uart_port *port)
 326 {
 327         return 0;
 328 }
 329
 330 static void jsm_config_port(struct uart_port *port, int flags)
 331 {
 332         port->type = PORT_JSM;
 333 }
 334
 335 static struct uart_ops jsm_ops = {
 336         .tx_empty       = jsm_tty_tx_empty,
 337         .set_mctrl      = jsm_tty_set_mctrl,
 338         .get_mctrl      = jsm_tty_get_mctrl,
 339         .stop_tx        = jsm_tty_stop_tx,
 340         .start_tx       = jsm_tty_start_tx,
 341         .send_xchar     = jsm_tty_send_xchar,
 342         .stop_rx        = jsm_tty_stop_rx,
 343         .break_ctl      = jsm_tty_break,
 344         .startup        = jsm_tty_open,
 345         .shutdown       = jsm_tty_close,
 346         .set_termios    = jsm_tty_set_termios,
 347         .type           = jsm_tty_type,
 348         .release_port   = jsm_tty_release_port,
 349         .request_port   = jsm_tty_request_port,
 350         .config_port    = jsm_config_port,
 351 };
 352
 353 /*
 354  * jsm_tty_init()
 355  *
 356  * Init the tty subsystem.  Called once per board after board has been
 357  * downloaded and init'ed.
 358  */
 359 int jsm_tty_init(struct jsm_board *brd)
 360 {
 361         int i;
 362         void __iomem *vaddr;
 363         struct jsm_channel *ch;
 364
 365         if (!brd)
 366                 return -ENXIO;
 367
 368         jsm_printk(INIT, INFO, &brd->pci_dev, "start\n");
 369
 370         /*
 371          * Initialize board structure elements.
 372          */
 373
 374         brd->nasync = brd->maxports;
 375
 376         /*
 377          * Allocate channel memory that might not have been allocated
 378          * when the driver was first loaded.
 379          */
 380         for (i = 0; i < brd->nasync; i++) {
 381                 if (!brd->channels[i]) {
 382
 383                         /*
 384                          * Okay to malloc with GFP_KERNEL, we are not at
 385                          * interrupt context, and there are no locks held.
 386                          */
 387                         brd->channels[i] = kmalloc(sizeof(struct jsm_channel), GFP_KERNEL);
 388                         if (!brd->channels[i]) {
 389                                 jsm_printk(CORE, ERR, &brd->pci_dev,
 390                                         "%s:%d Unable to allocate memory for channel struct\n",
 391                                                          __FILE__, __LINE__);
 392                         }
 393                         memset(brd->channels[i], 0, sizeof(struct jsm_channel));
 394                 }
 395         }
 396
 397         ch = brd->channels[0];
 398         vaddr = brd->re_map_membase;
 399
 400         /* Set up channel variables */
 401         for (i = 0; i < brd->nasync; i++, ch = brd->channels[i]) {
 402
 403                 if (!brd->channels[i])
 404                         continue;
 405
 406                 spin_lock_init(&ch->ch_lock);
 407
 408                 if (brd->bd_uart_offset == 0x200)
 409                         ch->ch_neo_uart =  vaddr + (brd->bd_uart_offset * i);
 410
 411                 ch->ch_bd = brd;
 412                 ch->ch_portnum = i;
 413
 414                 /* .25 second delay */
 415                 ch->ch_close_delay = 250;
 416
 417                 init_waitqueue_head(&ch->ch_flags_wait);
 418         }
 419
 420         jsm_printk(INIT, INFO, &brd->pci_dev, "finish\n");
 421         return 0;
 422 }
 423
 424 int jsm_uart_port_init(struct jsm_board *brd)
 425 {
 426         int i;
 427         struct jsm_channel *ch;
 428
 429         if (!brd)
 430                 return -ENXIO;
 431
 432         jsm_printk(INIT, INFO, &brd->pci_dev, "start\n");
 433
 434         /*
 435          * Initialize board structure elements.
 436          */
 437
 438         brd->nasync = brd->maxports;
 439
 440         /* Set up channel variables */
 441         for (i = 0; i < brd->nasync; i++, ch = brd->channels[i]) {
 442
 443                 if (!brd->channels[i])
 444                         continue;
 445
 446                 brd->channels[i]->uart_port.irq = brd->irq;
 447                 brd->channels[i]->uart_port.type = PORT_JSM;
 448                 brd->channels[i]->uart_port.iotype = UPIO_MEM;
 449                 brd->channels[i]->uart_port.membase = brd->re_map_membase;
 450                 brd->channels[i]->uart_port.fifosize = 16;
 451                 brd->channels[i]->uart_port.ops = &jsm_ops;
 452                 brd->channels[i]->uart_port.line = brd->channels[i]->ch_portnum + brd->boardnum * 2;
 453                 if (uart_add_one_port (&jsm_uart_driver, &brd->channels[i]->uart_port))
 454                         printk(KERN_INFO "Added device failed\n");
 455                 else
 456                         printk(KERN_INFO "Added device \n");
 457         }
 458
 459         jsm_printk(INIT, INFO, &brd->pci_dev, "finish\n");
 460         return 0;
 461 }
 462
 463 int jsm_remove_uart_port(struct jsm_board *brd)
 464 {
 465         int i;
 466         struct jsm_channel *ch;
 467
 468         if (!brd)
 469                 return -ENXIO;
 470
 471         jsm_printk(INIT, INFO, &brd->pci_dev, "start\n");
 472
 473         /*
 474          * Initialize board structure elements.
 475          */
 476
 477         brd->nasync = brd->maxports;
 478
 479         /* Set up channel variables */
 480         for (i = 0; i < brd->nasync; i++) {
 481
 482                 if (!brd->channels[i])
 483                         continue;
 484
 485                 ch = brd->channels[i];
 486
 487                 uart_remove_one_port(&jsm_uart_driver, &brd->channels[i]->uart_port);
 488         }
 489
 490         jsm_printk(INIT, INFO, &brd->pci_dev, "finish\n");
 491         return 0;
 492 }
 493
 494 void jsm_input(struct jsm_channel *ch)
 495 {
 496         struct jsm_board *bd;
 497         struct tty_struct *tp;
 498         u32 rmask;
 499         u16 head;
 500         u16 tail;
 501         int data_len;
 502         unsigned long lock_flags;
 503         int flip_len;
 504         int len = 0;
 505         int n = 0;
 506         char *buf = NULL;
 507         char *buf2 = NULL;
 508         int s = 0;
 509         int i = 0;
 510
 511         jsm_printk(READ, INFO, &ch->ch_bd->pci_dev, "start\n");
 512
 513         if (!ch)
 514                 return;
 515
 516         tp = ch->uart_port.info->tty;
 517
 518         bd = ch->ch_bd;
 519         if(!bd)
 520                 return;
 521
 522         spin_lock_irqsave(&ch->ch_lock, lock_flags);
 523
 524         /*
 525          *Figure the number of characters in the buffer.
 526          *Exit immediately if none.
 527          */
 528
 529         rmask = RQUEUEMASK;
 530
 531         head = ch->ch_r_head & rmask;
 532         tail = ch->ch_r_tail & rmask;
 533
 534         data_len = (head - tail) & rmask;
 535         if (data_len == 0) {
 536                 spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
 537                 return;
 538         }
 539
 540         jsm_printk(READ, INFO, &ch->ch_bd->pci_dev, "start\n");
 541
 542         /*
 543          *If the device is not open, or CREAD is off, flush
 544          *input data and return immediately.
 545          */
 546         if (!tp ||
 547                 !(tp->termios->c_cflag & CREAD) ) {
 548
 549                 jsm_printk(READ, INFO, &ch->ch_bd->pci_dev,
 550                         "input. dropping %d bytes on port %d...\n", data_len, ch->ch_portnum);
 551                 ch->ch_r_head = tail;
 552
 553                 /* Force queue flow control to be released, if needed */
 554                 jsm_check_queue_flow_control(ch);
 555
 556                 spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
 557                 return;
 558         }
 559
 560         /*
 561          * If we are throttled, simply don't read any data.
 562          */
 563         if (ch->ch_flags & CH_STOPI) {
 564                 spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
 565                 jsm_printk(READ, INFO, &ch->ch_bd->pci_dev,
 566                         "Port %d throttled, not reading any data. head: %x tail: %x\n",
 567                         ch->ch_portnum, head, tail);
 568                 return;
 569         }
 570
 571         jsm_printk(READ, INFO, &ch->ch_bd->pci_dev, "start 2\n");
 572
 573         /*
 574          * If the rxbuf is empty and we are not throttled, put as much
 575          * as we can directly into the linux TTY flip buffer.
 576          * The jsm_rawreadok case takes advantage of carnal knowledge that
 577          * the char_buf and the flag_buf are next to each other and
 578          * are each of (2 * TTY_FLIPBUF_SIZE) size.
 579          *
 580          * NOTE: if(!tty->real_raw), the call to ldisc.receive_buf
 581          *actually still uses the flag buffer, so you can't
 582          *use it for input data
 583          */
 584         if (jsm_rawreadok) {
 585                 if (tp->real_raw)
 586                         flip_len = MYFLIPLEN;
 587                 else
 588                         flip_len = 2 * TTY_FLIPBUF_SIZE;
 589         } else
 590                 flip_len = TTY_FLIPBUF_SIZE - tp->flip.count;
 591
 592         len = min(data_len, flip_len);
 593         len = min(len, (N_TTY_BUF_SIZE - 1) - tp->read_cnt);
 594
 595         if (len <= 0) {
 596                 spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
 597                 jsm_printk(READ, INFO, &ch->ch_bd->pci_dev, "jsm_input 1\n");
 598                 return;
 599         }
 600
 601         /*
 602          * If we're bypassing flip buffers on rx, we can blast it
 603          * right into the beginning of the buffer.
 604          */
 605         if (jsm_rawreadok) {
 606                 if (tp->real_raw) {
 607                         if (ch->ch_flags & CH_FLIPBUF_IN_USE) {
 608                                 jsm_printk(READ, INFO, &ch->ch_bd->pci_dev,
 609                                         "JSM - FLIPBUF in use. delaying input\n");
 610                                 spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
 611                                 return;
 612                         }
 613                         ch->ch_flags |= CH_FLIPBUF_IN_USE;
 614                         buf = ch->ch_bd->flipbuf;
 615                         buf2 = NULL;
 616                 } else {
 617                         buf = tp->flip.char_buf;
 618                         buf2 = tp->flip.flag_buf;
 619                 }
 620         } else {
 621                 buf = tp->flip.char_buf_ptr;
 622                 buf2 = tp->flip.flag_buf_ptr;
 623         }
 624
 625         n = len;
 626
 627         /*
 628          * n now contains the most amount of data we can copy,
 629          * bounded either by the flip buffer size or the amount
 630          * of data the card actually has pending...
 631          */
 632         while (n) {
 633                 s = ((head >= tail) ? head : RQUEUESIZE) - tail;
 634                 s = min(s, n);
 635
 636                 if (s <= 0)
 637                         break;
 638
 639                 memcpy(buf, ch->ch_rqueue + tail, s);
 640
 641                 /* buf2 is only set when port isn't raw */
 642                 if (buf2)
 643                         memcpy(buf2, ch->ch_equeue + tail, s);
 644
 645                 tail += s;
 646                 buf += s;
 647                 if (buf2)
 648                         buf2 += s;
 649                 n -= s;
 650                 /* Flip queue if needed */
 651                 tail &= rmask;
 652         }
 653
 654         /*
 655          * In high performance mode, we don't have to update
 656          * flag_buf or any of the counts or pointers into flip buf.
 657          */
 658         if (!jsm_rawreadok) {
 659                 if (I_PARMRK(tp) || I_BRKINT(tp) || I_INPCK(tp)) {
 660                         for (i = 0; i < len; i++) {
 661                                 /*
 662                                  * Give the Linux ld the flags in the
 663                                  * format it likes.
 664                                  */
 665                                 if (tp->flip.flag_buf_ptr[i] & UART_LSR_BI)
 666                                         tp->flip.flag_buf_ptr[i] = TTY_BREAK;
 667                                 else if (tp->flip.flag_buf_ptr[i] & UART_LSR_PE)
 668                                         tp->flip.flag_buf_ptr[i] = TTY_PARITY;
 669                                 else if (tp->flip.flag_buf_ptr[i] & UART_LSR_FE)
 670                                         tp->flip.flag_buf_ptr[i] = TTY_FRAME;
 671                                 else
 672                                         tp->flip.flag_buf_ptr[i] = TTY_NORMAL;
 673                         }
 674                 } else {
 675                         memset(tp->flip.flag_buf_ptr, 0, len);
 676                 }
 677
 678                 tp->flip.char_buf_ptr += len;
 679                 tp->flip.flag_buf_ptr += len;
 680                 tp->flip.count += len;
 681         }
 682         else if (!tp->real_raw) {
 683                 if (I_PARMRK(tp) || I_BRKINT(tp) || I_INPCK(tp)) {
 684                         for (i = 0; i < len; i++) {
 685                                 /*
 686                                  * Give the Linux ld the flags in the
 687                                  * format it likes.
 688                                  */
 689                                 if (tp->flip.flag_buf_ptr[i] & UART_LSR_BI)
 690                                         tp->flip.flag_buf_ptr[i] = TTY_BREAK;
 691                                 else if (tp->flip.flag_buf_ptr[i] & UART_LSR_PE)
 692                                         tp->flip.flag_buf_ptr[i] = TTY_PARITY;
 693                                 else if (tp->flip.flag_buf_ptr[i] & UART_LSR_FE)
 694                                         tp->flip.flag_buf_ptr[i] = TTY_FRAME;
 695                                 else
 696                                         tp->flip.flag_buf_ptr[i] = TTY_NORMAL;
 697                         }
 698                 } else
 699                         memset(tp->flip.flag_buf, 0, len);
 700         }
 701
 702         /*
 703          * If we're doing raw reads, jam it right into the
 704          * line disc bypassing the flip buffers.
 705          */
 706         if (jsm_rawreadok) {
 707                 if (tp->real_raw) {
 708                         ch->ch_r_tail = tail & rmask;
 709                         ch->ch_e_tail = tail & rmask;
 710
 711                         jsm_check_queue_flow_control(ch);
 712
 713                         /* !!! WE *MUST* LET GO OF ALL LOCKS BEFORE CALLING RECEIVE BUF !!! */
 714
 715                         spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
 716
 717                         jsm_printk(READ, INFO, &ch->ch_bd->pci_dev,
 718                                 "jsm_input. %d real_raw len:%d calling receive_buf for board %d\n",
 719                                 __LINE__, len, ch->ch_bd->boardnum);
 720                         tp->ldisc.receive_buf(tp, ch->ch_bd->flipbuf, NULL, len);
 721
 722                         /* Allow use of channel flip buffer again */
 723                         spin_lock_irqsave(&ch->ch_lock, lock_flags);
 724                         ch->ch_flags &= ~CH_FLIPBUF_IN_USE;
 725                         spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
 726
 727                 } else {
 728                         ch->ch_r_tail = tail & rmask;
 729                         ch->ch_e_tail = tail & rmask;
 730
 731                         jsm_check_queue_flow_control(ch);
 732
 733                         /* !!! WE *MUST* LET GO OF ALL LOCKS BEFORE CALLING RECEIVE BUF !!! */
 734                         spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
 735
 736                         jsm_printk(READ, INFO, &ch->ch_bd->pci_dev,
 737                                 "jsm_input. %d not real_raw len:%d calling receive_buf for board %d\n",
 738                                 __LINE__, len, ch->ch_bd->boardnum);
 739
 740                         tp->ldisc.receive_buf(tp, tp->flip.char_buf, tp->flip.flag_buf, len);
 741                 }
 742         } else {
 743                 ch->ch_r_tail = tail & rmask;
 744                 ch->ch_e_tail = tail & rmask;
 745
 746                 jsm_check_queue_flow_control(ch);
 747
 748                 spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
 749
 750                 jsm_printk(READ, INFO, &ch->ch_bd->pci_dev,
 751                         "jsm_input. %d not jsm_read raw okay scheduling flip\n", __LINE__);
 752                 tty_schedule_flip(tp);
 753         }
 754
 755         jsm_printk(IOCTL, INFO, &ch->ch_bd->pci_dev, "finish\n");
 756 }
 757
 758 void jsm_carrier(struct jsm_channel *ch)
 759 {
 760         struct jsm_board *bd;
 761
 762         int virt_carrier = 0;
 763         int phys_carrier = 0;
 764
 765         jsm_printk(CARR, INFO, &ch->ch_bd->pci_dev, "start\n");
 766         if (!ch)
 767                 return;
 768
 769         bd = ch->ch_bd;
 770
 771         if (!bd)
 772                 return;
 773
 774         if (ch->ch_mistat & UART_MSR_DCD) {
 775                 jsm_printk(CARR, INFO, &ch->ch_bd->pci_dev,
 776                         "mistat: %x D_CD: %x\n", ch->ch_mistat, ch->ch_mistat & UART_MSR_DCD);
 777                 phys_carrier = 1;
 778         }
 779
 780         if (ch->ch_c_cflag & CLOCAL)
 781                 virt_carrier = 1;
 782
 783         jsm_printk(CARR, INFO, &ch->ch_bd->pci_dev,
 784                 "DCD: physical: %d virt: %d\n", phys_carrier, virt_carrier);
 785
 786         /*
 787          * Test for a VIRTUAL carrier transition to HIGH.
 788          */
 789         if (((ch->ch_flags & CH_FCAR) == 0) && (virt_carrier == 1)) {
 790
 791                 /*
 792                  * When carrier rises, wake any threads waiting
 793                  * for carrier in the open routine.
 794                  */
 795
 796                 jsm_printk(CARR, INFO, &ch->ch_bd->pci_dev,
 797                         "carrier: virt DCD rose\n");
 798
 799                 if (waitqueue_active(&(ch->ch_flags_wait)))
 800                         wake_up_interruptible(&ch->ch_flags_wait);
 801         }
 802
 803         /*
 804          * Test for a PHYSICAL carrier transition to HIGH.
 805          */
 806         if (((ch->ch_flags & CH_CD) == 0) && (phys_carrier == 1)) {
 807
 808                 /*
 809                  * When carrier rises, wake any threads waiting
 810                  * for carrier in the open routine.
 811                  */
 812
 813                 jsm_printk(CARR, INFO, &ch->ch_bd->pci_dev,
 814                         "carrier: physical DCD rose\n");
 815
 816                 if (waitqueue_active(&(ch->ch_flags_wait)))
 817                         wake_up_interruptible(&ch->ch_flags_wait);
 818         }
 819
 820         /*
 821          *  Test for a PHYSICAL transition to low, so long as we aren't
 822          *  currently ignoring physical transitions (which is what "virtual
 823          *  carrier" indicates).
 824          *
 825          *  The transition of the virtual carrier to low really doesn't
 826          *  matter... it really only means "ignore carrier state", not
 827          *  "make pretend that carrier is there".
 828          */
 829         if ((virt_carrier == 0) && ((ch->ch_flags & CH_CD) != 0)
 830                         && (phys_carrier == 0)) {
 831                 /*
 832                  *      When carrier drops:
 833                  *
 834                  *      Drop carrier on all open units.
 835                  *
 836                  *      Flush queues, waking up any task waiting in the
 837                  *      line discipline.
 838                  *
 839                  *      Send a hangup to the control terminal.
 840                  *
 841                  *      Enable all select calls.
 842                  */
 843                 if (waitqueue_active(&(ch->ch_flags_wait)))
 844                         wake_up_interruptible(&ch->ch_flags_wait);
 845         }
 846
 847         /*
 848          *  Make sure that our cached values reflect the current reality.
 849          */
 850         if (virt_carrier == 1)
 851                 ch->ch_flags |= CH_FCAR;
 852         else
 853                 ch->ch_flags &= ~CH_FCAR;
 854
 855         if (phys_carrier == 1)
 856                 ch->ch_flags |= CH_CD;
 857         else
 858                 ch->ch_flags &= ~CH_CD;
 859 }
 860
 861
 862 void jsm_check_queue_flow_control(struct jsm_channel *ch)
 863 {
 864         int qleft = 0;
 865
 866         /* Store how much space we have left in the queue */
 867         if ((qleft = ch->ch_r_tail - ch->ch_r_head - 1) < 0)
 868                 qleft += RQUEUEMASK + 1;
 869
 870         /*
 871          * Check to see if we should enforce flow control on our queue because
 872          * the ld (or user) isn't reading data out of our queue fast enuf.
 873          *
 874          * NOTE: This is done based on what the current flow control of the
 875          * port is set for.
 876          *
 877          * 1) HWFLOW (RTS) - Turn off the UART's Receive interrupt.
 878          *      This will cause the UART's FIFO to back up, and force
 879          *      the RTS signal to be dropped.
 880          * 2) SWFLOW (IXOFF) - Keep trying to send a stop character to
 881          *      the other side, in hopes it will stop sending data to us.
 882          * 3) NONE - Nothing we can do.  We will simply drop any extra data
 883          *      that gets sent into us when the queue fills up.
 884          */
 885         if (qleft < 256) {
 886                 /* HWFLOW */
 887                 if (ch->ch_c_cflag & CRTSCTS) {
 888                         if(!(ch->ch_flags & CH_RECEIVER_OFF)) {
 889                                 ch->ch_bd->bd_ops->disable_receiver(ch);
 890                                 ch->ch_flags |= (CH_RECEIVER_OFF);
 891                                 jsm_printk(READ, INFO, &ch->ch_bd->pci_dev,
 892                                         "Internal queue hit hilevel mark (%d)! Turning off interrupts.\n",
 893                                         qleft);
 894                         }
 895                 }
 896                 /* SWFLOW */
 897                 else if (ch->ch_c_iflag & IXOFF) {
 898                         if (ch->ch_stops_sent <= MAX_STOPS_SENT) {
 899                                 ch->ch_bd->bd_ops->send_stop_character(ch);
 900                                 ch->ch_stops_sent++;
 901                                 jsm_printk(READ, INFO, &ch->ch_bd->pci_dev,
 902                                         "Sending stop char! Times sent: %x\n", ch->ch_stops_sent);
 903                         }
 904                 }
 905         }
 906
 907         /*
 908          * Check to see if we should unenforce flow control because
 909          * ld (or user) finally read enuf data out of our queue.
 910          *
 911          * NOTE: This is done based on what the current flow control of the
 912          * port is set for.
 913          *
 914          * 1) HWFLOW (RTS) - Turn back on the UART's Receive interrupt.
 915          *      This will cause the UART's FIFO to raise RTS back up,
 916          *      which will allow the other side to start sending data again.
 917          * 2) SWFLOW (IXOFF) - Send a start character to
 918          *      the other side, so it will start sending data to us again.
 919          * 3) NONE - Do nothing. Since we didn't do anything to turn off the
 920          *      other side, we don't need to do anything now.
 921          */
 922         if (qleft > (RQUEUESIZE / 2)) {
 923                 /* HWFLOW */
 924                 if (ch->ch_c_cflag & CRTSCTS) {
 925                         if (ch->ch_flags & CH_RECEIVER_OFF) {
 926                                 ch->ch_bd->bd_ops->enable_receiver(ch);
 927                                 ch->ch_flags &= ~(CH_RECEIVER_OFF);
 928                                 jsm_printk(READ, INFO, &ch->ch_bd->pci_dev,
 929                                         "Internal queue hit lowlevel mark (%d)! Turning on interrupts.\n",
 930                                         qleft);
 931                         }
 932                 }
 933                 /* SWFLOW */
 934                 else if (ch->ch_c_iflag & IXOFF && ch->ch_stops_sent) {
 935                         ch->ch_stops_sent = 0;
 936                         ch->ch_bd->bd_ops->send_start_character(ch);
 937                         jsm_printk(READ, INFO, &ch->ch_bd->pci_dev, "Sending start char!\n");
 938                 }
 939         }
 940 }
 941
 942 /*
 943  * jsm_tty_write()
 944  *
 945  * Take data from the user or kernel and send it out to the FEP.
 946  * In here exists all the Transparent Print magic as well.
 947  */
 948 int jsm_tty_write(struct uart_port *port)
 949 {
 950         int bufcount = 0, n = 0;
 951         int data_count = 0,data_count1 =0;
 952         u16 head;
 953         u16 tail;
 954         u16 tmask;
 955         u32 remain;
 956         int temp_tail = port->info->xmit.tail;
 957         struct jsm_channel *channel = (struct jsm_channel *)port;
 958
 959         tmask = WQUEUEMASK;
 960         head = (channel->ch_w_head) & tmask;
 961         tail = (channel->ch_w_tail) & tmask;
 962
 963         if ((bufcount = tail - head - 1) < 0)
 964                 bufcount += WQUEUESIZE;
 965
 966         n = bufcount;
 967
 968         n = min(n, 56);
 969         remain = WQUEUESIZE - head;
 970
 971         data_count = 0;
 972         if (n >= remain) {
 973                 n -= remain;
 974                 while ((port->info->xmit.head != temp_tail) &&
 975                 (data_count < remain)) {
 976                         channel->ch_wqueue[head++] =
 977                         port->info->xmit.buf[temp_tail];
 978
 979                         temp_tail++;
 980                         temp_tail &= (UART_XMIT_SIZE - 1);
 981                         data_count++;
 982                 }
 983                 if (data_count == remain) head = 0;
 984         }
 985
 986         data_count1 = 0;
 987         if (n > 0) {
 988                 remain = n;
 989                 while ((port->info->xmit.head != temp_tail) &&
 990                         (data_count1 < remain)) {
 991                         channel->ch_wqueue[head++] =
 992                                 port->info->xmit.buf[temp_tail];
 993
 994                         temp_tail++;
 995                         temp_tail &= (UART_XMIT_SIZE - 1);
 996                         data_count1++;
 997
 998                 }
 999         }
1000
1001         port->info->xmit.tail = temp_tail;
1002
1003         data_count += data_count1;
1004         if (data_count) {
1005                 head &= tmask;
1006                 channel->ch_w_head = head;
1007         }
1008
1009         if (data_count) {
1010                 channel->ch_bd->bd_ops->copy_data_from_queue_to_uart(channel);
1011         }
1012
1013         return data_count;
1014 }
1015
1016 static ssize_t jsm_driver_version_show(struct device_driver *ddp, char *buf)
1017 {
1018         return snprintf(buf, PAGE_SIZE, "%s\n", JSM_VERSION);
1019 }
1020 static DRIVER_ATTR(version, S_IRUSR, jsm_driver_version_show, NULL);
1021
1022 static ssize_t jsm_driver_state_show(struct device_driver *ddp, char *buf)
1023 {
1024         return snprintf(buf, PAGE_SIZE, "%s\n", jsm_driver_state_text[jsm_driver_state]);
1025 }
1026 static DRIVER_ATTR(state, S_IRUSR, jsm_driver_state_show, NULL);
1027
1028 void jsm_create_driver_sysfiles(struct device_driver *driverfs)
1029 {
1030         driver_create_file(driverfs, &driver_attr_version);
1031         driver_create_file(driverfs, &driver_attr_state);
1032 }
1033
1034 void jsm_remove_driver_sysfiles(struct device_driver *driverfs)
1035 {
1036         driver_remove_file(driverfs, &driver_attr_version);
1037         driver_remove_file(driverfs, &driver_attr_state);
1038 }