drivers/tty/serial/jsm/jsm_neo.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.ibm.com>
  24  *
  25  ***********************************************************************/
  26 #include <linux/delay.h>        /* For udelay */
  27 #include <linux/serial_reg.h>   /* For the various UART offsets */
  28 #include <linux/tty.h>
  29 #include <linux/pci.h>
  30 #include <asm/io.h>
  31
  32 #include "jsm.h"                /* Driver main header file */
  33
  34 static u32 jsm_offset_table[8] = { 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80 };
  35
  36 /*
  37  * This function allows calls to ensure that all outstanding
  38  * PCI writes have been completed, by doing a PCI read against
  39  * a non-destructive, read-only location on the Neo card.
  40  *
  41  * In this case, we are reading the DVID (Read-only Device Identification)
  42  * value of the Neo card.
  43  */
  44 static inline void neo_pci_posting_flush(struct jsm_board *bd)
  45 {
  46       readb(bd->re_map_membase + 0x8D);
  47 }
  48
  49 static void neo_set_cts_flow_control(struct jsm_channel *ch)
  50 {
  51         u8 ier, efr;
  52         ier = readb(&ch->ch_neo_uart->ier);
  53         efr = readb(&ch->ch_neo_uart->efr);
  54
  55         jsm_printk(PARAM, INFO, &ch->ch_bd->pci_dev, "Setting CTSFLOW\n");
  56
  57         /* Turn on auto CTS flow control */
  58         ier |= (UART_17158_IER_CTSDSR);
  59         efr |= (UART_17158_EFR_ECB | UART_17158_EFR_CTSDSR);
  60
  61         /* Turn off auto Xon flow control */
  62         efr &= ~(UART_17158_EFR_IXON);
  63
  64         /* Why? Becuz Exar's spec says we have to zero it out before setting it */
  65         writeb(0, &ch->ch_neo_uart->efr);
  66
  67         /* Turn on UART enhanced bits */
  68         writeb(efr, &ch->ch_neo_uart->efr);
  69
  70         /* Turn on table D, with 8 char hi/low watermarks */
  71         writeb((UART_17158_FCTR_TRGD | UART_17158_FCTR_RTS_4DELAY), &ch->ch_neo_uart->fctr);
  72
  73         /* Feed the UART our trigger levels */
  74         writeb(8, &ch->ch_neo_uart->tfifo);
  75         ch->ch_t_tlevel = 8;
  76
  77         writeb(ier, &ch->ch_neo_uart->ier);
  78 }
  79
  80 static void neo_set_rts_flow_control(struct jsm_channel *ch)
  81 {
  82         u8 ier, efr;
  83         ier = readb(&ch->ch_neo_uart->ier);
  84         efr = readb(&ch->ch_neo_uart->efr);
  85
  86         jsm_printk(PARAM, INFO, &ch->ch_bd->pci_dev, "Setting RTSFLOW\n");
  87
  88         /* Turn on auto RTS flow control */
  89         ier |= (UART_17158_IER_RTSDTR);
  90         efr |= (UART_17158_EFR_ECB | UART_17158_EFR_RTSDTR);
  91
  92         /* Turn off auto Xoff flow control */
  93         ier &= ~(UART_17158_IER_XOFF);
  94         efr &= ~(UART_17158_EFR_IXOFF);
  95
  96         /* Why? Becuz Exar's spec says we have to zero it out before setting it */
  97         writeb(0, &ch->ch_neo_uart->efr);
  98
  99         /* Turn on UART enhanced bits */
 100         writeb(efr, &ch->ch_neo_uart->efr);
 101
 102         writeb((UART_17158_FCTR_TRGD | UART_17158_FCTR_RTS_4DELAY), &ch->ch_neo_uart->fctr);
 103         ch->ch_r_watermark = 4;
 104
 105         writeb(56, &ch->ch_neo_uart->rfifo);
 106         ch->ch_r_tlevel = 56;
 107
 108         writeb(ier, &ch->ch_neo_uart->ier);
 109
 110         /*
 111          * From the Neo UART spec sheet:
 112          * The auto RTS/DTR function must be started by asserting
 113          * RTS/DTR# output pin (MCR bit-0 or 1 to logic 1 after
 114          * it is enabled.
 115          */
 116         ch->ch_mostat |= (UART_MCR_RTS);
 117 }
 118
 119
 120 static void neo_set_ixon_flow_control(struct jsm_channel *ch)
 121 {
 122         u8 ier, efr;
 123         ier = readb(&ch->ch_neo_uart->ier);
 124         efr = readb(&ch->ch_neo_uart->efr);
 125
 126         jsm_printk(PARAM, INFO, &ch->ch_bd->pci_dev, "Setting IXON FLOW\n");
 127
 128         /* Turn off auto CTS flow control */
 129         ier &= ~(UART_17158_IER_CTSDSR);
 130         efr &= ~(UART_17158_EFR_CTSDSR);
 131
 132         /* Turn on auto Xon flow control */
 133         efr |= (UART_17158_EFR_ECB | UART_17158_EFR_IXON);
 134
 135         /* Why? Becuz Exar's spec says we have to zero it out before setting it */
 136         writeb(0, &ch->ch_neo_uart->efr);
 137
 138         /* Turn on UART enhanced bits */
 139         writeb(efr, &ch->ch_neo_uart->efr);
 140
 141         writeb((UART_17158_FCTR_TRGD | UART_17158_FCTR_RTS_8DELAY), &ch->ch_neo_uart->fctr);
 142         ch->ch_r_watermark = 4;
 143
 144         writeb(32, &ch->ch_neo_uart->rfifo);
 145         ch->ch_r_tlevel = 32;
 146
 147         /* Tell UART what start/stop chars it should be looking for */
 148         writeb(ch->ch_startc, &ch->ch_neo_uart->xonchar1);
 149         writeb(0, &ch->ch_neo_uart->xonchar2);
 150
 151         writeb(ch->ch_stopc, &ch->ch_neo_uart->xoffchar1);
 152         writeb(0, &ch->ch_neo_uart->xoffchar2);
 153
 154         writeb(ier, &ch->ch_neo_uart->ier);
 155 }
 156
 157 static void neo_set_ixoff_flow_control(struct jsm_channel *ch)
 158 {
 159         u8 ier, efr;
 160         ier = readb(&ch->ch_neo_uart->ier);
 161         efr = readb(&ch->ch_neo_uart->efr);
 162
 163         jsm_printk(PARAM, INFO, &ch->ch_bd->pci_dev, "Setting IXOFF FLOW\n");
 164
 165         /* Turn off auto RTS flow control */
 166         ier &= ~(UART_17158_IER_RTSDTR);
 167         efr &= ~(UART_17158_EFR_RTSDTR);
 168
 169         /* Turn on auto Xoff flow control */
 170         ier |= (UART_17158_IER_XOFF);
 171         efr |= (UART_17158_EFR_ECB | UART_17158_EFR_IXOFF);
 172
 173         /* Why? Becuz Exar's spec says we have to zero it out before setting it */
 174         writeb(0, &ch->ch_neo_uart->efr);
 175
 176         /* Turn on UART enhanced bits */
 177         writeb(efr, &ch->ch_neo_uart->efr);
 178
 179         /* Turn on table D, with 8 char hi/low watermarks */
 180         writeb((UART_17158_FCTR_TRGD | UART_17158_FCTR_RTS_8DELAY), &ch->ch_neo_uart->fctr);
 181
 182         writeb(8, &ch->ch_neo_uart->tfifo);
 183         ch->ch_t_tlevel = 8;
 184
 185         /* Tell UART what start/stop chars it should be looking for */
 186         writeb(ch->ch_startc, &ch->ch_neo_uart->xonchar1);
 187         writeb(0, &ch->ch_neo_uart->xonchar2);
 188
 189         writeb(ch->ch_stopc, &ch->ch_neo_uart->xoffchar1);
 190         writeb(0, &ch->ch_neo_uart->xoffchar2);
 191
 192         writeb(ier, &ch->ch_neo_uart->ier);
 193 }
 194
 195 static void neo_set_no_input_flow_control(struct jsm_channel *ch)
 196 {
 197         u8 ier, efr;
 198         ier = readb(&ch->ch_neo_uart->ier);
 199         efr = readb(&ch->ch_neo_uart->efr);
 200
 201         jsm_printk(PARAM, INFO, &ch->ch_bd->pci_dev, "Unsetting Input FLOW\n");
 202
 203         /* Turn off auto RTS flow control */
 204         ier &= ~(UART_17158_IER_RTSDTR);
 205         efr &= ~(UART_17158_EFR_RTSDTR);
 206
 207         /* Turn off auto Xoff flow control */
 208         ier &= ~(UART_17158_IER_XOFF);
 209         if (ch->ch_c_iflag & IXON)
 210                 efr &= ~(UART_17158_EFR_IXOFF);
 211         else
 212                 efr &= ~(UART_17158_EFR_ECB | UART_17158_EFR_IXOFF);
 213
 214         /* Why? Becuz Exar's spec says we have to zero it out before setting it */
 215         writeb(0, &ch->ch_neo_uart->efr);
 216
 217         /* Turn on UART enhanced bits */
 218         writeb(efr, &ch->ch_neo_uart->efr);
 219
 220         /* Turn on table D, with 8 char hi/low watermarks */
 221         writeb((UART_17158_FCTR_TRGD | UART_17158_FCTR_RTS_8DELAY), &ch->ch_neo_uart->fctr);
 222
 223         ch->ch_r_watermark = 0;
 224
 225         writeb(16, &ch->ch_neo_uart->tfifo);
 226         ch->ch_t_tlevel = 16;
 227
 228         writeb(16, &ch->ch_neo_uart->rfifo);
 229         ch->ch_r_tlevel = 16;
 230
 231         writeb(ier, &ch->ch_neo_uart->ier);
 232 }
 233
 234 static void neo_set_no_output_flow_control(struct jsm_channel *ch)
 235 {
 236         u8 ier, efr;
 237         ier = readb(&ch->ch_neo_uart->ier);
 238         efr = readb(&ch->ch_neo_uart->efr);
 239
 240         jsm_printk(PARAM, INFO, &ch->ch_bd->pci_dev, "Unsetting Output FLOW\n");
 241
 242         /* Turn off auto CTS flow control */
 243         ier &= ~(UART_17158_IER_CTSDSR);
 244         efr &= ~(UART_17158_EFR_CTSDSR);
 245
 246         /* Turn off auto Xon flow control */
 247         if (ch->ch_c_iflag & IXOFF)
 248                 efr &= ~(UART_17158_EFR_IXON);
 249         else
 250                 efr &= ~(UART_17158_EFR_ECB | UART_17158_EFR_IXON);
 251
 252         /* Why? Becuz Exar's spec says we have to zero it out before setting it */
 253         writeb(0, &ch->ch_neo_uart->efr);
 254
 255         /* Turn on UART enhanced bits */
 256         writeb(efr, &ch->ch_neo_uart->efr);
 257
 258         /* Turn on table D, with 8 char hi/low watermarks */
 259         writeb((UART_17158_FCTR_TRGD | UART_17158_FCTR_RTS_8DELAY), &ch->ch_neo_uart->fctr);
 260
 261         ch->ch_r_watermark = 0;
 262
 263         writeb(16, &ch->ch_neo_uart->tfifo);
 264         ch->ch_t_tlevel = 16;
 265
 266         writeb(16, &ch->ch_neo_uart->rfifo);
 267         ch->ch_r_tlevel = 16;
 268
 269         writeb(ier, &ch->ch_neo_uart->ier);
 270 }
 271
 272 static inline void neo_set_new_start_stop_chars(struct jsm_channel *ch)
 273 {
 274
 275         /* if hardware flow control is set, then skip this whole thing */
 276         if (ch->ch_c_cflag & CRTSCTS)
 277                 return;
 278
 279         jsm_printk(PARAM, INFO, &ch->ch_bd->pci_dev, "start\n");
 280
 281         /* Tell UART what start/stop chars it should be looking for */
 282         writeb(ch->ch_startc, &ch->ch_neo_uart->xonchar1);
 283         writeb(0, &ch->ch_neo_uart->xonchar2);
 284
 285         writeb(ch->ch_stopc, &ch->ch_neo_uart->xoffchar1);
 286         writeb(0, &ch->ch_neo_uart->xoffchar2);
 287 }
 288
 289 static void neo_copy_data_from_uart_to_queue(struct jsm_channel *ch)
 290 {
 291         int qleft = 0;
 292         u8 linestatus = 0;
 293         u8 error_mask = 0;
 294         int n = 0;
 295         int total = 0;
 296         u16 head;
 297         u16 tail;
 298
 299         if (!ch)
 300                 return;
 301
 302         /* cache head and tail of queue */
 303         head = ch->ch_r_head & RQUEUEMASK;
 304         tail = ch->ch_r_tail & RQUEUEMASK;
 305
 306         /* Get our cached LSR */
 307         linestatus = ch->ch_cached_lsr;
 308         ch->ch_cached_lsr = 0;
 309
 310         /* Store how much space we have left in the queue */
 311         if ((qleft = tail - head - 1) < 0)
 312                 qleft += RQUEUEMASK + 1;
 313
 314         /*
 315          * If the UART is not in FIFO mode, force the FIFO copy to
 316          * NOT be run, by setting total to 0.
 317          *
 318          * On the other hand, if the UART IS in FIFO mode, then ask
 319          * the UART to give us an approximation of data it has RX'ed.
 320          */
 321         if (!(ch->ch_flags & CH_FIFO_ENABLED))
 322                 total = 0;
 323         else {
 324                 total = readb(&ch->ch_neo_uart->rfifo);
 325
 326                 /*
 327                  * EXAR chip bug - RX FIFO COUNT - Fudge factor.
 328                  *
 329                  * This resolves a problem/bug with the Exar chip that sometimes
 330                  * returns a bogus value in the rfifo register.
 331                  * The count can be any where from 0-3 bytes "off".
 332                  * Bizarre, but true.
 333                  */
 334                 total -= 3;
 335         }
 336
 337         /*
 338          * Finally, bound the copy to make sure we don't overflow
 339          * our own queue...
 340          * The byte by byte copy loop below this loop this will
 341          * deal with the queue overflow possibility.
 342          */
 343         total = min(total, qleft);
 344
 345         while (total > 0) {
 346                 /*
 347                  * Grab the linestatus register, we need to check
 348                  * to see if there are any errors in the FIFO.
 349                  */
 350                 linestatus = readb(&ch->ch_neo_uart->lsr);
 351
 352                 /*
 353                  * Break out if there is a FIFO error somewhere.
 354                  * This will allow us to go byte by byte down below,
 355                  * finding the exact location of the error.
 356                  */
 357                 if (linestatus & UART_17158_RX_FIFO_DATA_ERROR)
 358                         break;
 359
 360                 /* Make sure we don't go over the end of our queue */
 361                 n = min(((u32) total), (RQUEUESIZE - (u32) head));
 362
 363                 /*
 364                  * Cut down n even further if needed, this is to fix
 365                  * a problem with memcpy_fromio() with the Neo on the
 366                  * IBM pSeries platform.
 367                  * 15 bytes max appears to be the magic number.
 368                  */
 369                 n = min((u32) n, (u32) 12);
 370
 371                 /*
 372                  * Since we are grabbing the linestatus register, which
 373                  * will reset some bits after our read, we need to ensure
 374                  * we don't miss our TX FIFO emptys.
 375                  */
 376                 if (linestatus & (UART_LSR_THRE | UART_17158_TX_AND_FIFO_CLR))
 377                         ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
 378
 379                 linestatus = 0;
 380
 381                 /* Copy data from uart to the queue */
 382                 memcpy_fromio(ch->ch_rqueue + head, &ch->ch_neo_uart->txrxburst, n);
 383                 /*
 384                  * Since RX_FIFO_DATA_ERROR was 0, we are guarenteed
 385                  * that all the data currently in the FIFO is free of
 386                  * breaks and parity/frame/orun errors.
 387                  */
 388                 memset(ch->ch_equeue + head, 0, n);
 389
 390                 /* Add to and flip head if needed */
 391                 head = (head + n) & RQUEUEMASK;
 392                 total -= n;
 393                 qleft -= n;
 394                 ch->ch_rxcount += n;
 395         }
 396
 397         /*
 398          * Create a mask to determine whether we should
 399          * insert the character (if any) into our queue.
 400          */
 401         if (ch->ch_c_iflag & IGNBRK)
 402                 error_mask |= UART_LSR_BI;
 403
 404         /*
 405          * Now cleanup any leftover bytes still in the UART.
 406          * Also deal with any possible queue overflow here as well.
 407          */
 408         while (1) {
 409
 410                 /*
 411                  * Its possible we have a linestatus from the loop above
 412                  * this, so we "OR" on any extra bits.
 413                  */
 414                 linestatus |= readb(&ch->ch_neo_uart->lsr);
 415
 416                 /*
 417                  * If the chip tells us there is no more data pending to
 418                  * be read, we can then leave.
 419                  * But before we do, cache the linestatus, just in case.
 420                  */
 421                 if (!(linestatus & UART_LSR_DR)) {
 422                         ch->ch_cached_lsr = linestatus;
 423                         break;
 424                 }
 425
 426                 /* No need to store this bit */
 427                 linestatus &= ~UART_LSR_DR;
 428
 429                 /*
 430                  * Since we are grabbing the linestatus register, which
 431                  * will reset some bits after our read, we need to ensure
 432                  * we don't miss our TX FIFO emptys.
 433                  */
 434                 if (linestatus & (UART_LSR_THRE | UART_17158_TX_AND_FIFO_CLR)) {
 435                         linestatus &= ~(UART_LSR_THRE | UART_17158_TX_AND_FIFO_CLR);
 436                         ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
 437                 }
 438
 439                 /*
 440                  * Discard character if we are ignoring the error mask.
 441                  */
 442                 if (linestatus & error_mask) {
 443                         u8 discard;
 444                         linestatus = 0;
 445                         memcpy_fromio(&discard, &ch->ch_neo_uart->txrxburst, 1);
 446                         continue;
 447                 }
 448
 449                 /*
 450                  * If our queue is full, we have no choice but to drop some data.
 451                  * The assumption is that HWFLOW or SWFLOW should have stopped
 452                  * things way way before we got to this point.
 453                  *
 454                  * I decided that I wanted to ditch the oldest data first,
 455                  * I hope thats okay with everyone? Yes? Good.
 456                  */
 457                 while (qleft < 1) {
 458                         jsm_printk(READ, INFO, &ch->ch_bd->pci_dev,
 459                                 "Queue full, dropping DATA:%x LSR:%x\n",
 460                                 ch->ch_rqueue[tail], ch->ch_equeue[tail]);
 461
 462                         ch->ch_r_tail = tail = (tail + 1) & RQUEUEMASK;
 463                         ch->ch_err_overrun++;
 464                         qleft++;
 465                 }
 466
 467                 memcpy_fromio(ch->ch_rqueue + head, &ch->ch_neo_uart->txrxburst, 1);
 468                 ch->ch_equeue[head] = (u8) linestatus;
 469
 470                 jsm_printk(READ, INFO, &ch->ch_bd->pci_dev,
 471                                 "DATA/LSR pair: %x %x\n", ch->ch_rqueue[head], ch->ch_equeue[head]);
 472
 473                 /* Ditch any remaining linestatus value. */
 474                 linestatus = 0;
 475
 476                 /* Add to and flip head if needed */
 477                 head = (head + 1) & RQUEUEMASK;
 478
 479                 qleft--;
 480                 ch->ch_rxcount++;
 481         }
 482
 483         /*
 484          * Write new final heads to channel structure.
 485          */
 486         ch->ch_r_head = head & RQUEUEMASK;
 487         ch->ch_e_head = head & EQUEUEMASK;
 488         jsm_input(ch);
 489 }
 490
 491 static void neo_copy_data_from_queue_to_uart(struct jsm_channel *ch)
 492 {
 493         u16 head;
 494         u16 tail;
 495         int n;
 496         int s;
 497         int qlen;
 498         u32 len_written = 0;
 499
 500         if (!ch)
 501                 return;
 502
 503         /* No data to write to the UART */
 504         if (ch->ch_w_tail == ch->ch_w_head)
 505                 return;
 506
 507         /* If port is "stopped", don't send any data to the UART */
 508         if ((ch->ch_flags & CH_STOP) || (ch->ch_flags & CH_BREAK_SENDING))
 509                 return;
 510         /*
 511          * If FIFOs are disabled. Send data directly to txrx register
 512          */
 513         if (!(ch->ch_flags & CH_FIFO_ENABLED)) {
 514                 u8 lsrbits = readb(&ch->ch_neo_uart->lsr);
 515
 516                 ch->ch_cached_lsr |= lsrbits;
 517                 if (ch->ch_cached_lsr & UART_LSR_THRE) {
 518                         ch->ch_cached_lsr &= ~(UART_LSR_THRE);
 519
 520                         writeb(ch->ch_wqueue[ch->ch_w_tail], &ch->ch_neo_uart->txrx);
 521                         jsm_printk(WRITE, INFO, &ch->ch_bd->pci_dev,
 522                                         "Tx data: %x\n", ch->ch_wqueue[ch->ch_w_head]);
 523                         ch->ch_w_tail++;
 524                         ch->ch_w_tail &= WQUEUEMASK;
 525                         ch->ch_txcount++;
 526                 }
 527                 return;
 528         }
 529
 530         /*
 531          * We have to do it this way, because of the EXAR TXFIFO count bug.
 532          */
 533         if (!(ch->ch_flags & (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM)))
 534                 return;
 535
 536         n = UART_17158_TX_FIFOSIZE - ch->ch_t_tlevel;
 537
 538         /* cache head and tail of queue */
 539         head = ch->ch_w_head & WQUEUEMASK;
 540         tail = ch->ch_w_tail & WQUEUEMASK;
 541         qlen = (head - tail) & WQUEUEMASK;
 542
 543         /* Find minimum of the FIFO space, versus queue length */
 544         n = min(n, qlen);
 545
 546         while (n > 0) {
 547
 548                 s = ((head >= tail) ? head : WQUEUESIZE) - tail;
 549                 s = min(s, n);
 550
 551                 if (s <= 0)
 552                         break;
 553
 554                 memcpy_toio(&ch->ch_neo_uart->txrxburst, ch->ch_wqueue + tail, s);
 555                 /* Add and flip queue if needed */
 556                 tail = (tail + s) & WQUEUEMASK;
 557                 n -= s;
 558                 ch->ch_txcount += s;
 559                 len_written += s;
 560         }
 561
 562         /* Update the final tail */
 563         ch->ch_w_tail = tail & WQUEUEMASK;
 564
 565         if (len_written >= ch->ch_t_tlevel)
 566                 ch->ch_flags &= ~(CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
 567
 568         if (!jsm_tty_write(&ch->uart_port))
 569                 uart_write_wakeup(&ch->uart_port);
 570 }
 571
 572 static void neo_parse_modem(struct jsm_channel *ch, u8 signals)
 573 {
 574         u8 msignals = signals;
 575
 576         jsm_printk(MSIGS, INFO, &ch->ch_bd->pci_dev,
 577                         "neo_parse_modem: port: %d msignals: %x\n", ch->ch_portnum, msignals);
 578
 579         /* Scrub off lower bits. They signify delta's, which I don't care about */
 580         /* Keep DDCD and DDSR though */
 581         msignals &= 0xf8;
 582
 583         if (msignals & UART_MSR_DDCD)
 584                 uart_handle_dcd_change(&ch->uart_port, msignals & UART_MSR_DCD);
 585         if (msignals & UART_MSR_DDSR)
 586                 uart_handle_cts_change(&ch->uart_port, msignals & UART_MSR_CTS);
 587         if (msignals & UART_MSR_DCD)
 588                 ch->ch_mistat |= UART_MSR_DCD;
 589         else
 590                 ch->ch_mistat &= ~UART_MSR_DCD;
 591
 592         if (msignals & UART_MSR_DSR)
 593                 ch->ch_mistat |= UART_MSR_DSR;
 594         else
 595                 ch->ch_mistat &= ~UART_MSR_DSR;
 596
 597         if (msignals & UART_MSR_RI)
 598                 ch->ch_mistat |= UART_MSR_RI;
 599         else
 600                 ch->ch_mistat &= ~UART_MSR_RI;
 601
 602         if (msignals & UART_MSR_CTS)
 603                 ch->ch_mistat |= UART_MSR_CTS;
 604         else
 605                 ch->ch_mistat &= ~UART_MSR_CTS;
 606
 607         jsm_printk(MSIGS, INFO, &ch->ch_bd->pci_dev,
 608                         "Port: %d DTR: %d RTS: %d CTS: %d DSR: %d " "RI: %d CD: %d\n",
 609                 ch->ch_portnum,
 610                 !!((ch->ch_mistat | ch->ch_mostat) & UART_MCR_DTR),
 611                 !!((ch->ch_mistat | ch->ch_mostat) & UART_MCR_RTS),
 612                 !!((ch->ch_mistat | ch->ch_mostat) & UART_MSR_CTS),
 613                 !!((ch->ch_mistat | ch->ch_mostat) & UART_MSR_DSR),
 614                 !!((ch->ch_mistat | ch->ch_mostat) & UART_MSR_RI),
 615                 !!((ch->ch_mistat | ch->ch_mostat) & UART_MSR_DCD));
 616 }
 617
 618 /* Make the UART raise any of the output signals we want up */
 619 static void neo_assert_modem_signals(struct jsm_channel *ch)
 620 {
 621         if (!ch)
 622                 return;
 623
 624         writeb(ch->ch_mostat, &ch->ch_neo_uart->mcr);
 625
 626         /* flush write operation */
 627         neo_pci_posting_flush(ch->ch_bd);
 628 }
 629
 630 /*
 631  * Flush the WRITE FIFO on the Neo.
 632  *
 633  * NOTE: Channel lock MUST be held before calling this function!
 634  */
 635 static void neo_flush_uart_write(struct jsm_channel *ch)
 636 {
 637         u8 tmp = 0;
 638         int i = 0;
 639
 640         if (!ch)
 641                 return;
 642
 643         writeb((UART_FCR_ENABLE_FIFO | UART_FCR_CLEAR_XMIT), &ch->ch_neo_uart->isr_fcr);
 644
 645         for (i = 0; i < 10; i++) {
 646
 647                 /* Check to see if the UART feels it completely flushed the FIFO. */
 648                 tmp = readb(&ch->ch_neo_uart->isr_fcr);
 649                 if (tmp & 4) {
 650                         jsm_printk(IOCTL, INFO, &ch->ch_bd->pci_dev,
 651                                         "Still flushing TX UART... i: %d\n", i);
 652                         udelay(10);
 653                 }
 654                 else
 655                         break;
 656         }
 657
 658         ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
 659 }
 660
 661
 662 /*
 663  * Flush the READ FIFO on the Neo.
 664  *
 665  * NOTE: Channel lock MUST be held before calling this function!
 666  */
 667 static void neo_flush_uart_read(struct jsm_channel *ch)
 668 {
 669         u8 tmp = 0;
 670         int i = 0;
 671
 672         if (!ch)
 673                 return;
 674
 675         writeb((UART_FCR_ENABLE_FIFO | UART_FCR_CLEAR_RCVR), &ch->ch_neo_uart->isr_fcr);
 676
 677         for (i = 0; i < 10; i++) {
 678
 679                 /* Check to see if the UART feels it completely flushed the FIFO. */
 680                 tmp = readb(&ch->ch_neo_uart->isr_fcr);
 681                 if (tmp & 2) {
 682                         jsm_printk(IOCTL, INFO, &ch->ch_bd->pci_dev,
 683                                         "Still flushing RX UART... i: %d\n", i);
 684                         udelay(10);
 685                 }
 686                 else
 687                         break;
 688         }
 689 }
 690
 691 /*
 692  * No locks are assumed to be held when calling this function.
 693  */
 694 static void neo_clear_break(struct jsm_channel *ch, int force)
 695 {
 696         unsigned long lock_flags;
 697
 698         spin_lock_irqsave(&ch->ch_lock, lock_flags);
 699
 700         /* Turn break off, and unset some variables */
 701         if (ch->ch_flags & CH_BREAK_SENDING) {
 702                 u8 temp = readb(&ch->ch_neo_uart->lcr);
 703                 writeb((temp & ~UART_LCR_SBC), &ch->ch_neo_uart->lcr);
 704
 705                 ch->ch_flags &= ~(CH_BREAK_SENDING);
 706                 jsm_printk(IOCTL, INFO, &ch->ch_bd->pci_dev,
 707                                 "clear break Finishing UART_LCR_SBC! finished: %lx\n", jiffies);
 708
 709                 /* flush write operation */
 710                 neo_pci_posting_flush(ch->ch_bd);
 711         }
 712         spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
 713 }
 714
 715 /*
 716  * Parse the ISR register.
 717  */
 718 static inline void neo_parse_isr(struct jsm_board *brd, u32 port)
 719 {
 720         struct jsm_channel *ch;
 721         u8 isr;
 722         u8 cause;
 723         unsigned long lock_flags;
 724
 725         if (!brd)
 726                 return;
 727
 728         if (port > brd->maxports)
 729                 return;
 730
 731         ch = brd->channels[port];
 732         if (!ch)
 733                 return;
 734
 735         /* Here we try to figure out what caused the interrupt to happen */
 736         while (1) {
 737
 738                 isr = readb(&ch->ch_neo_uart->isr_fcr);
 739
 740                 /* Bail if no pending interrupt */
 741                 if (isr & UART_IIR_NO_INT)
 742                         break;
 743
 744                 /*
 745                  * Yank off the upper 2 bits, which just show that the FIFO's are enabled.
 746                  */
 747                 isr &= ~(UART_17158_IIR_FIFO_ENABLED);
 748
 749                 jsm_printk(INTR, INFO, &ch->ch_bd->pci_dev,
 750                                 "%s:%d isr: %x\n", __FILE__, __LINE__, isr);
 751
 752                 if (isr & (UART_17158_IIR_RDI_TIMEOUT | UART_IIR_RDI)) {
 753                         /* Read data from uart -> queue */
 754                         neo_copy_data_from_uart_to_queue(ch);
 755
 756                         /* Call our tty layer to enforce queue flow control if needed. */
 757                         spin_lock_irqsave(&ch->ch_lock, lock_flags);
 758                         jsm_check_queue_flow_control(ch);
 759                         spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
 760                 }
 761
 762                 if (isr & UART_IIR_THRI) {
 763                         /* Transfer data (if any) from Write Queue -> UART. */
 764                         spin_lock_irqsave(&ch->ch_lock, lock_flags);
 765                         ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
 766                         spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
 767                         neo_copy_data_from_queue_to_uart(ch);
 768                 }
 769
 770                 if (isr & UART_17158_IIR_XONXOFF) {
 771                         cause = readb(&ch->ch_neo_uart->xoffchar1);
 772
 773                         jsm_printk(INTR, INFO, &ch->ch_bd->pci_dev,
 774                                         "Port %d. Got ISR_XONXOFF: cause:%x\n", port, cause);
 775
 776                         /*
 777                          * Since the UART detected either an XON or
 778                          * XOFF match, we need to figure out which
 779                          * one it was, so we can suspend or resume data flow.
 780                          */
 781                         spin_lock_irqsave(&ch->ch_lock, lock_flags);
 782                         if (cause == UART_17158_XON_DETECT) {
 783                                 /* Is output stopped right now, if so, resume it */
 784                                 if (brd->channels[port]->ch_flags & CH_STOP) {
 785                                         ch->ch_flags &= ~(CH_STOP);
 786                                 }
 787                                 jsm_printk(INTR, INFO, &ch->ch_bd->pci_dev,
 788                                                 "Port %d. XON detected in incoming data\n", port);
 789                         }
 790                         else if (cause == UART_17158_XOFF_DETECT) {
 791                                 if (!(brd->channels[port]->ch_flags & CH_STOP)) {
 792                                         ch->ch_flags |= CH_STOP;
 793                                         jsm_printk(INTR, INFO, &ch->ch_bd->pci_dev,
 794                                                         "Setting CH_STOP\n");
 795                                 }
 796                                 jsm_printk(INTR, INFO, &ch->ch_bd->pci_dev,
 797                                                 "Port: %d. XOFF detected in incoming data\n", port);
 798                         }
 799                         spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
 800                 }
 801
 802                 if (isr & UART_17158_IIR_HWFLOW_STATE_CHANGE) {
 803                         /*
 804                          * If we get here, this means the hardware is doing auto flow control.
 805                          * Check to see whether RTS/DTR or CTS/DSR caused this interrupt.
 806                          */
 807                         cause = readb(&ch->ch_neo_uart->mcr);
 808
 809                         /* Which pin is doing auto flow? RTS or DTR? */
 810                         spin_lock_irqsave(&ch->ch_lock, lock_flags);
 811                         if ((cause & 0x4) == 0) {
 812                                 if (cause & UART_MCR_RTS)
 813                                         ch->ch_mostat |= UART_MCR_RTS;
 814                                 else
 815                                         ch->ch_mostat &= ~(UART_MCR_RTS);
 816                         } else {
 817                                 if (cause & UART_MCR_DTR)
 818                                         ch->ch_mostat |= UART_MCR_DTR;
 819                                 else
 820                                         ch->ch_mostat &= ~(UART_MCR_DTR);
 821                         }
 822                         spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
 823                 }
 824
 825                 /* Parse any modem signal changes */
 826                 jsm_printk(INTR, INFO, &ch->ch_bd->pci_dev,
 827                                 "MOD_STAT: sending to parse_modem_sigs\n");
 828                 neo_parse_modem(ch, readb(&ch->ch_neo_uart->msr));
 829         }
 830 }
 831
 832 static inline void neo_parse_lsr(struct jsm_board *brd, u32 port)
 833 {
 834         struct jsm_channel *ch;
 835         int linestatus;
 836         unsigned long lock_flags;
 837
 838         if (!brd)
 839                 return;
 840
 841         if (port > brd->maxports)
 842                 return;
 843
 844         ch = brd->channels[port];
 845         if (!ch)
 846                 return;
 847
 848         linestatus = readb(&ch->ch_neo_uart->lsr);
 849
 850         jsm_printk(INTR, INFO, &ch->ch_bd->pci_dev,
 851                         "%s:%d port: %d linestatus: %x\n", __FILE__, __LINE__, port, linestatus);
 852
 853         ch->ch_cached_lsr |= linestatus;
 854
 855         if (ch->ch_cached_lsr & UART_LSR_DR) {
 856                 /* Read data from uart -> queue */
 857                 neo_copy_data_from_uart_to_queue(ch);
 858                 spin_lock_irqsave(&ch->ch_lock, lock_flags);
 859                 jsm_check_queue_flow_control(ch);
 860                 spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
 861         }
 862
 863         /*
 864          * This is a special flag. It indicates that at least 1
 865          * RX error (parity, framing, or break) has happened.
 866          * Mark this in our struct, which will tell me that I have
 867          *to do the special RX+LSR read for this FIFO load.
 868          */
 869         if (linestatus & UART_17158_RX_FIFO_DATA_ERROR)
 870                 jsm_printk(INTR, DEBUG, &ch->ch_bd->pci_dev,
 871                         "%s:%d Port: %d Got an RX error, need to parse LSR\n",
 872                         __FILE__, __LINE__, port);
 873
 874         /*
 875          * The next 3 tests should *NOT* happen, as the above test
 876          * should encapsulate all 3... At least, thats what Exar says.
 877          */
 878
 879         if (linestatus & UART_LSR_PE) {
 880                 ch->ch_err_parity++;
 881                 jsm_printk(INTR, DEBUG, &ch->ch_bd->pci_dev,
 882                         "%s:%d Port: %d. PAR ERR!\n", __FILE__, __LINE__, port);
 883         }
 884
 885         if (linestatus & UART_LSR_FE) {
 886                 ch->ch_err_frame++;
 887                 jsm_printk(INTR, DEBUG, &ch->ch_bd->pci_dev,
 888                         "%s:%d Port: %d. FRM ERR!\n", __FILE__, __LINE__, port);
 889         }
 890
 891         if (linestatus & UART_LSR_BI) {
 892                 ch->ch_err_break++;
 893                 jsm_printk(INTR, DEBUG, &ch->ch_bd->pci_dev,
 894                         "%s:%d Port: %d. BRK INTR!\n", __FILE__, __LINE__, port);
 895         }
 896
 897         if (linestatus & UART_LSR_OE) {
 898                 /*
 899                  * Rx Oruns. Exar says that an orun will NOT corrupt
 900                  * the FIFO. It will just replace the holding register
 901                  * with this new data byte. So basically just ignore this.
 902                  * Probably we should eventually have an orun stat in our driver...
 903                  */
 904                 ch->ch_err_overrun++;
 905                 jsm_printk(INTR, DEBUG, &ch->ch_bd->pci_dev,
 906                         "%s:%d Port: %d. Rx Overrun!\n", __FILE__, __LINE__, port);
 907         }
 908
 909         if (linestatus & UART_LSR_THRE) {
 910                 spin_lock_irqsave(&ch->ch_lock, lock_flags);
 911                 ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
 912                 spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
 913
 914                 /* Transfer data (if any) from Write Queue -> UART. */
 915                 neo_copy_data_from_queue_to_uart(ch);
 916         }
 917         else if (linestatus & UART_17158_TX_AND_FIFO_CLR) {
 918                 spin_lock_irqsave(&ch->ch_lock, lock_flags);
 919                 ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
 920                 spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
 921
 922                 /* Transfer data (if any) from Write Queue -> UART. */
 923                 neo_copy_data_from_queue_to_uart(ch);
 924         }
 925 }
 926
 927 /*
 928  * neo_param()
 929  * Send any/all changes to the line to the UART.
 930  */
 931 static void neo_param(struct jsm_channel *ch)
 932 {
 933         u8 lcr = 0;
 934         u8 uart_lcr, ier;
 935         u32 baud;
 936         int quot;
 937         struct jsm_board *bd;
 938
 939         bd = ch->ch_bd;
 940         if (!bd)
 941                 return;
 942
 943         /*
 944          * If baud rate is zero, flush queues, and set mval to drop DTR.
 945          */
 946         if ((ch->ch_c_cflag & (CBAUD)) == 0) {
 947                 ch->ch_r_head = ch->ch_r_tail = 0;
 948                 ch->ch_e_head = ch->ch_e_tail = 0;
 949                 ch->ch_w_head = ch->ch_w_tail = 0;
 950
 951                 neo_flush_uart_write(ch);
 952                 neo_flush_uart_read(ch);
 953
 954                 ch->ch_flags |= (CH_BAUD0);
 955                 ch->ch_mostat &= ~(UART_MCR_RTS | UART_MCR_DTR);
 956                 neo_assert_modem_signals(ch);
 957                 return;
 958
 959         } else {
 960                 int i;
 961                 unsigned int cflag;
 962                 static struct {
 963                         unsigned int rate;
 964                         unsigned int cflag;
 965                 } baud_rates[] = {
 966                         { 921600, B921600 },
 967                         { 460800, B460800 },
 968                         { 230400, B230400 },
 969                         { 115200, B115200 },
 970                         {  57600, B57600  },
 971                         {  38400, B38400  },
 972                         {  19200, B19200  },
 973                         {   9600, B9600   },
 974                         {   4800, B4800   },
 975                         {   2400, B2400   },
 976                         {   1200, B1200   },
 977                         {    600, B600    },
 978                         {    300, B300    },
 979                         {    200, B200    },
 980                         {    150, B150    },
 981                         {    134, B134    },
 982                         {    110, B110    },
 983                         {     75, B75     },
 984                         {     50, B50     },
 985                 };
 986
 987                 cflag = C_BAUD(ch->uart_port.state->port.tty);
 988                 baud = 9600;
 989                 for (i = 0; i < ARRAY_SIZE(baud_rates); i++) {
 990                         if (baud_rates[i].cflag == cflag) {
 991                                 baud = baud_rates[i].rate;
 992                                 break;
 993                         }
 994                 }
 995
 996                 if (ch->ch_flags & CH_BAUD0)
 997                         ch->ch_flags &= ~(CH_BAUD0);
 998         }
 999
1000         if (ch->ch_c_cflag & PARENB)
1001                 lcr |= UART_LCR_PARITY;
1002
1003         if (!(ch->ch_c_cflag & PARODD))
1004                 lcr |= UART_LCR_EPAR;
1005
1006         /*
1007          * Not all platforms support mark/space parity,
1008          * so this will hide behind an ifdef.
1009          */
1010 #ifdef CMSPAR
1011         if (ch->ch_c_cflag & CMSPAR)
1012                 lcr |= UART_LCR_SPAR;
1013 #endif
1014
1015         if (ch->ch_c_cflag & CSTOPB)
1016                 lcr |= UART_LCR_STOP;
1017
1018         switch (ch->ch_c_cflag & CSIZE) {
1019                 case CS5:
1020                         lcr |= UART_LCR_WLEN5;
1021                         break;
1022                 case CS6:
1023                         lcr |= UART_LCR_WLEN6;
1024                         break;
1025                 case CS7:
1026                         lcr |= UART_LCR_WLEN7;
1027                         break;
1028                 case CS8:
1029                 default:
1030                         lcr |= UART_LCR_WLEN8;
1031                 break;
1032         }
1033
1034         ier = readb(&ch->ch_neo_uart->ier);
1035         uart_lcr = readb(&ch->ch_neo_uart->lcr);
1036
1037         if (baud == 0)
1038                 baud = 9600;
1039
1040         quot = ch->ch_bd->bd_dividend / baud;
1041
1042         if (quot != 0) {
1043                 writeb(UART_LCR_DLAB, &ch->ch_neo_uart->lcr);
1044                 writeb((quot & 0xff), &ch->ch_neo_uart->txrx);
1045                 writeb((quot >> 8), &ch->ch_neo_uart->ier);
1046                 writeb(lcr, &ch->ch_neo_uart->lcr);
1047         }
1048
1049         if (uart_lcr != lcr)
1050                 writeb(lcr, &ch->ch_neo_uart->lcr);
1051
1052         if (ch->ch_c_cflag & CREAD)
1053                 ier |= (UART_IER_RDI | UART_IER_RLSI);
1054
1055         ier |= (UART_IER_THRI | UART_IER_MSI);
1056
1057         writeb(ier, &ch->ch_neo_uart->ier);
1058
1059         /* Set new start/stop chars */
1060         neo_set_new_start_stop_chars(ch);
1061
1062         if (ch->ch_c_cflag & CRTSCTS)
1063                 neo_set_cts_flow_control(ch);
1064         else if (ch->ch_c_iflag & IXON) {
1065                 /* If start/stop is set to disable, then we should disable flow control */
1066                 if ((ch->ch_startc == __DISABLED_CHAR) || (ch->ch_stopc == __DISABLED_CHAR))
1067                         neo_set_no_output_flow_control(ch);
1068                 else
1069                         neo_set_ixon_flow_control(ch);
1070         }
1071         else
1072                 neo_set_no_output_flow_control(ch);
1073
1074         if (ch->ch_c_cflag & CRTSCTS)
1075                 neo_set_rts_flow_control(ch);
1076         else if (ch->ch_c_iflag & IXOFF) {
1077                 /* If start/stop is set to disable, then we should disable flow control */
1078                 if ((ch->ch_startc == __DISABLED_CHAR) || (ch->ch_stopc == __DISABLED_CHAR))
1079                         neo_set_no_input_flow_control(ch);
1080                 else
1081                         neo_set_ixoff_flow_control(ch);
1082         }
1083         else
1084                 neo_set_no_input_flow_control(ch);
1085         /*
1086          * Adjust the RX FIFO Trigger level if baud is less than 9600.
1087          * Not exactly elegant, but this is needed because of the Exar chip's
1088          * delay on firing off the RX FIFO interrupt on slower baud rates.
1089          */
1090         if (baud < 9600) {
1091                 writeb(1, &ch->ch_neo_uart->rfifo);
1092                 ch->ch_r_tlevel = 1;
1093         }
1094
1095         neo_assert_modem_signals(ch);
1096
1097         /* Get current status of the modem signals now */
1098         neo_parse_modem(ch, readb(&ch->ch_neo_uart->msr));
1099         return;
1100 }
1101
1102 /*
1103  * jsm_neo_intr()
1104  *
1105  * Neo specific interrupt handler.
1106  */
1107 static irqreturn_t neo_intr(int irq, void *voidbrd)
1108 {
1109         struct jsm_board *brd = voidbrd;
1110         struct jsm_channel *ch;
1111         int port = 0;
1112         int type = 0;
1113         int current_port;
1114         u32 tmp;
1115         u32 uart_poll;
1116         unsigned long lock_flags;
1117         unsigned long lock_flags2;
1118         int outofloop_count = 0;
1119
1120         /* Lock out the slow poller from running on this board. */
1121         spin_lock_irqsave(&brd->bd_intr_lock, lock_flags);
1122
1123         /*
1124          * Read in "extended" IRQ information from the 32bit Neo register.
1125          * Bits 0-7: What port triggered the interrupt.
1126          * Bits 8-31: Each 3bits indicate what type of interrupt occurred.
1127          */
1128         uart_poll = readl(brd->re_map_membase + UART_17158_POLL_ADDR_OFFSET);
1129
1130         jsm_printk(INTR, INFO, &brd->pci_dev,
1131                 "%s:%d uart_poll: %x\n", __FILE__, __LINE__, uart_poll);
1132
1133         if (!uart_poll) {
1134                 jsm_printk(INTR, INFO, &brd->pci_dev,
1135                         "Kernel interrupted to me, but no pending interrupts...\n");
1136                 spin_unlock_irqrestore(&brd->bd_intr_lock, lock_flags);
1137                 return IRQ_NONE;
1138         }
1139
1140         /* At this point, we have at least SOMETHING to service, dig further... */
1141
1142         current_port = 0;
1143
1144         /* Loop on each port */
1145         while (((uart_poll & 0xff) != 0) && (outofloop_count < 0xff)){
1146
1147                 tmp = uart_poll;
1148                 outofloop_count++;
1149
1150                 /* Check current port to see if it has interrupt pending */
1151                 if ((tmp & jsm_offset_table[current_port]) != 0) {
1152                         port = current_port;
1153                         type = tmp >> (8 + (port * 3));
1154                         type &= 0x7;
1155                 } else {
1156                         current_port++;
1157                         continue;
1158                 }
1159
1160                 jsm_printk(INTR, INFO, &brd->pci_dev,
1161                 "%s:%d port: %x type: %x\n", __FILE__, __LINE__, port, type);
1162
1163                 /* Remove this port + type from uart_poll */
1164                 uart_poll &= ~(jsm_offset_table[port]);
1165
1166                 if (!type) {
1167                         /* If no type, just ignore it, and move onto next port */
1168                         jsm_printk(INTR, ERR, &brd->pci_dev,
1169                                 "Interrupt with no type! port: %d\n", port);
1170                         continue;
1171                 }
1172
1173                 /* Switch on type of interrupt we have */
1174                 switch (type) {
1175
1176                 case UART_17158_RXRDY_TIMEOUT:
1177                         /*
1178                          * RXRDY Time-out is cleared by reading data in the
1179                         * RX FIFO until it falls below the trigger level.
1180                          */
1181
1182                         /* Verify the port is in range. */
1183                         if (port > brd->nasync)
1184                                 continue;
1185
1186                         ch = brd->channels[port];
1187                         neo_copy_data_from_uart_to_queue(ch);
1188
1189                         /* Call our tty layer to enforce queue flow control if needed. */
1190                         spin_lock_irqsave(&ch->ch_lock, lock_flags2);
1191                         jsm_check_queue_flow_control(ch);
1192                         spin_unlock_irqrestore(&ch->ch_lock, lock_flags2);
1193
1194                         continue;
1195
1196                 case UART_17158_RX_LINE_STATUS:
1197                         /*
1198                          * RXRDY and RX LINE Status (logic OR of LSR[4:1])
1199                          */
1200                         neo_parse_lsr(brd, port);
1201                         continue;
1202
1203                 case UART_17158_TXRDY:
1204                         /*
1205                          * TXRDY interrupt clears after reading ISR register for the UART channel.
1206                          */
1207
1208                         /*
1209                          * Yes, this is odd...
1210                          * Why would I check EVERY possibility of type of
1211                          * interrupt, when we know its TXRDY???
1212                          * Becuz for some reason, even tho we got triggered for TXRDY,
1213                          * it seems to be occassionally wrong. Instead of TX, which
1214                          * it should be, I was getting things like RXDY too. Weird.
1215                          */
1216                         neo_parse_isr(brd, port);
1217                         continue;
1218
1219                 case UART_17158_MSR:
1220                         /*
1221                          * MSR or flow control was seen.
1222                          */
1223                         neo_parse_isr(brd, port);
1224                         continue;
1225
1226                 default:
1227                         /*
1228                          * The UART triggered us with a bogus interrupt type.
1229                          * It appears the Exar chip, when REALLY bogged down, will throw
1230                          * these once and awhile.
1231                          * Its harmless, just ignore it and move on.
1232                          */
1233                         jsm_printk(INTR, ERR, &brd->pci_dev,
1234                                 "%s:%d Unknown Interrupt type: %x\n", __FILE__, __LINE__, type);
1235                         continue;
1236                 }
1237         }
1238
1239         spin_unlock_irqrestore(&brd->bd_intr_lock, lock_flags);
1240
1241         jsm_printk(INTR, INFO, &brd->pci_dev, "finish.\n");
1242         return IRQ_HANDLED;
1243 }
1244
1245 /*
1246  * Neo specific way of turning off the receiver.
1247  * Used as a way to enforce queue flow control when in
1248  * hardware flow control mode.
1249  */
1250 static void neo_disable_receiver(struct jsm_channel *ch)
1251 {
1252         u8 tmp = readb(&ch->ch_neo_uart->ier);
1253         tmp &= ~(UART_IER_RDI);
1254         writeb(tmp, &ch->ch_neo_uart->ier);
1255
1256         /* flush write operation */
1257         neo_pci_posting_flush(ch->ch_bd);
1258 }
1259
1260
1261 /*
1262  * Neo specific way of turning on the receiver.
1263  * Used as a way to un-enforce queue flow control when in
1264  * hardware flow control mode.
1265  */
1266 static void neo_enable_receiver(struct jsm_channel *ch)
1267 {
1268         u8 tmp = readb(&ch->ch_neo_uart->ier);
1269         tmp |= (UART_IER_RDI);
1270         writeb(tmp, &ch->ch_neo_uart->ier);
1271
1272         /* flush write operation */
1273         neo_pci_posting_flush(ch->ch_bd);
1274 }
1275
1276 static void neo_send_start_character(struct jsm_channel *ch)
1277 {
1278         if (!ch)
1279                 return;
1280
1281         if (ch->ch_startc != __DISABLED_CHAR) {
1282                 ch->ch_xon_sends++;
1283                 writeb(ch->ch_startc, &ch->ch_neo_uart->txrx);
1284
1285                 /* flush write operation */
1286                 neo_pci_posting_flush(ch->ch_bd);
1287         }
1288 }
1289
1290 static void neo_send_stop_character(struct jsm_channel *ch)
1291 {
1292         if (!ch)
1293                 return;
1294
1295         if (ch->ch_stopc != __DISABLED_CHAR) {
1296                 ch->ch_xoff_sends++;
1297                 writeb(ch->ch_stopc, &ch->ch_neo_uart->txrx);
1298
1299                 /* flush write operation */
1300                 neo_pci_posting_flush(ch->ch_bd);
1301         }
1302 }
1303
1304 /*
1305  * neo_uart_init
1306  */
1307 static void neo_uart_init(struct jsm_channel *ch)
1308 {
1309         writeb(0, &ch->ch_neo_uart->ier);
1310         writeb(0, &ch->ch_neo_uart->efr);
1311         writeb(UART_EFR_ECB, &ch->ch_neo_uart->efr);
1312
1313         /* Clear out UART and FIFO */
1314         readb(&ch->ch_neo_uart->txrx);
1315         writeb((UART_FCR_ENABLE_FIFO|UART_FCR_CLEAR_RCVR|UART_FCR_CLEAR_XMIT), &ch->ch_neo_uart->isr_fcr);
1316         readb(&ch->ch_neo_uart->lsr);
1317         readb(&ch->ch_neo_uart->msr);
1318
1319         ch->ch_flags |= CH_FIFO_ENABLED;
1320
1321         /* Assert any signals we want up */
1322         writeb(ch->ch_mostat, &ch->ch_neo_uart->mcr);
1323 }
1324
1325 /*
1326  * Make the UART completely turn off.
1327  */
1328 static void neo_uart_off(struct jsm_channel *ch)
1329 {
1330         /* Turn off UART enhanced bits */
1331         writeb(0, &ch->ch_neo_uart->efr);
1332
1333         /* Stop all interrupts from occurring. */
1334         writeb(0, &ch->ch_neo_uart->ier);
1335 }
1336
1337 static u32 neo_get_uart_bytes_left(struct jsm_channel *ch)
1338 {
1339         u8 left = 0;
1340         u8 lsr = readb(&ch->ch_neo_uart->lsr);
1341
1342         /* We must cache the LSR as some of the bits get reset once read... */
1343         ch->ch_cached_lsr |= lsr;
1344
1345         /* Determine whether the Transmitter is empty or not */
1346         if (!(lsr & UART_LSR_TEMT))
1347                 left = 1;
1348         else {
1349                 ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
1350                 left = 0;
1351         }
1352
1353         return left;
1354 }
1355
1356 /* Channel lock MUST be held by the calling function! */
1357 static void neo_send_break(struct jsm_channel *ch)
1358 {
1359         /*
1360          * Set the time we should stop sending the break.
1361          * If we are already sending a break, toss away the existing
1362          * time to stop, and use this new value instead.
1363          */
1364
1365         /* Tell the UART to start sending the break */
1366         if (!(ch->ch_flags & CH_BREAK_SENDING)) {
1367                 u8 temp = readb(&ch->ch_neo_uart->lcr);
1368                 writeb((temp | UART_LCR_SBC), &ch->ch_neo_uart->lcr);
1369                 ch->ch_flags |= (CH_BREAK_SENDING);
1370
1371                 /* flush write operation */
1372                 neo_pci_posting_flush(ch->ch_bd);
1373         }
1374 }
1375
1376 /*
1377  * neo_send_immediate_char.
1378  *
1379  * Sends a specific character as soon as possible to the UART,
1380  * jumping over any bytes that might be in the write queue.
1381  *
1382  * The channel lock MUST be held by the calling function.
1383  */
1384 static void neo_send_immediate_char(struct jsm_channel *ch, unsigned char c)
1385 {
1386         if (!ch)
1387                 return;
1388
1389         writeb(c, &ch->ch_neo_uart->txrx);
1390
1391         /* flush write operation */
1392         neo_pci_posting_flush(ch->ch_bd);
1393 }
1394
1395 struct board_ops jsm_neo_ops = {
1396         .intr                           = neo_intr,
1397         .uart_init                      = neo_uart_init,
1398         .uart_off                       = neo_uart_off,
1399         .param                          = neo_param,
1400         .assert_modem_signals           = neo_assert_modem_signals,
1401         .flush_uart_write               = neo_flush_uart_write,
1402         .flush_uart_read                = neo_flush_uart_read,
1403         .disable_receiver               = neo_disable_receiver,
1404         .enable_receiver                = neo_enable_receiver,
1405         .send_break                     = neo_send_break,
1406         .clear_break                    = neo_clear_break,
1407         .send_start_character           = neo_send_start_character,
1408         .send_stop_character            = neo_send_stop_character,
1409         .copy_data_from_queue_to_uart   = neo_copy_data_from_queue_to_uart,
1410         .get_uart_bytes_left            = neo_get_uart_bytes_left,
1411         .send_immediate_char            = neo_send_immediate_char
1412 };