drivers/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         len_written = 0;
 537         n = UART_17158_TX_FIFOSIZE - ch->ch_t_tlevel;
 538
 539         /* cache head and tail of queue */
 540         head = ch->ch_w_head & WQUEUEMASK;
 541         tail = ch->ch_w_tail & WQUEUEMASK;
 542         qlen = (head - tail) & WQUEUEMASK;
 543
 544         /* Find minimum of the FIFO space, versus queue length */
 545         n = min(n, qlen);
 546
 547         while (n > 0) {
 548
 549                 s = ((head >= tail) ? head : WQUEUESIZE) - tail;
 550                 s = min(s, n);
 551
 552                 if (s <= 0)
 553                         break;
 554
 555                 memcpy_toio(&ch->ch_neo_uart->txrxburst, ch->ch_wqueue + tail, s);
 556                 /* Add and flip queue if needed */
 557                 tail = (tail + s) & WQUEUEMASK;
 558                 n -= s;
 559                 ch->ch_txcount += s;
 560                 len_written += s;
 561         }
 562
 563         /* Update the final tail */
 564         ch->ch_w_tail = tail & WQUEUEMASK;
 565
 566         if (len_written >= ch->ch_t_tlevel)
 567                 ch->ch_flags &= ~(CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
 568
 569         if (!jsm_tty_write(&ch->uart_port))
 570                 uart_write_wakeup(&ch->uart_port);
 571 }
 572
 573 static void neo_parse_modem(struct jsm_channel *ch, u8 signals)
 574 {
 575         u8 msignals = signals;
 576
 577         jsm_printk(MSIGS, INFO, &ch->ch_bd->pci_dev,
 578                         "neo_parse_modem: port: %d msignals: %x\n", ch->ch_portnum, msignals);
 579
 580         /* Scrub off lower bits. They signify delta's, which I don't care about */
 581         /* Keep DDCD and DDSR though */
 582         msignals &= 0xf8;
 583
 584         if (msignals & UART_MSR_DDCD)
 585                 uart_handle_dcd_change(&ch->uart_port, msignals & UART_MSR_DCD);
 586         if (msignals & UART_MSR_DDSR)
 587                 uart_handle_cts_change(&ch->uart_port, msignals & UART_MSR_CTS);
 588         if (msignals & UART_MSR_DCD)
 589                 ch->ch_mistat |= UART_MSR_DCD;
 590         else
 591                 ch->ch_mistat &= ~UART_MSR_DCD;
 592
 593         if (msignals & UART_MSR_DSR)
 594                 ch->ch_mistat |= UART_MSR_DSR;
 595         else
 596                 ch->ch_mistat &= ~UART_MSR_DSR;
 597
 598         if (msignals & UART_MSR_RI)
 599                 ch->ch_mistat |= UART_MSR_RI;
 600         else
 601                 ch->ch_mistat &= ~UART_MSR_RI;
 602
 603         if (msignals & UART_MSR_CTS)
 604                 ch->ch_mistat |= UART_MSR_CTS;
 605         else
 606                 ch->ch_mistat &= ~UART_MSR_CTS;
 607
 608         jsm_printk(MSIGS, INFO, &ch->ch_bd->pci_dev,
 609                         "Port: %d DTR: %d RTS: %d CTS: %d DSR: %d " "RI: %d CD: %d\n",
 610                 ch->ch_portnum,
 611                 !!((ch->ch_mistat | ch->ch_mostat) & UART_MCR_DTR),
 612                 !!((ch->ch_mistat | ch->ch_mostat) & UART_MCR_RTS),
 613                 !!((ch->ch_mistat | ch->ch_mostat) & UART_MSR_CTS),
 614                 !!((ch->ch_mistat | ch->ch_mostat) & UART_MSR_DSR),
 615                 !!((ch->ch_mistat | ch->ch_mostat) & UART_MSR_RI),
 616                 !!((ch->ch_mistat | ch->ch_mostat) & UART_MSR_DCD));
 617 }
 618
 619 /* Make the UART raise any of the output signals we want up */
 620 static void neo_assert_modem_signals(struct jsm_channel *ch)
 621 {
 622         u8 out;
 623
 624         if (!ch)
 625                 return;
 626
 627         out = ch->ch_mostat;
 628
 629         writeb(out, &ch->ch_neo_uart->mcr);
 630
 631         /* flush write operation */
 632         neo_pci_posting_flush(ch->ch_bd);
 633 }
 634
 635 /*
 636  * Flush the WRITE FIFO on the Neo.
 637  *
 638  * NOTE: Channel lock MUST be held before calling this function!
 639  */
 640 static void neo_flush_uart_write(struct jsm_channel *ch)
 641 {
 642         u8 tmp = 0;
 643         int i = 0;
 644
 645         if (!ch)
 646                 return;
 647
 648         writeb((UART_FCR_ENABLE_FIFO | UART_FCR_CLEAR_XMIT), &ch->ch_neo_uart->isr_fcr);
 649
 650         for (i = 0; i < 10; i++) {
 651
 652                 /* Check to see if the UART feels it completely flushed the FIFO. */
 653                 tmp = readb(&ch->ch_neo_uart->isr_fcr);
 654                 if (tmp & 4) {
 655                         jsm_printk(IOCTL, INFO, &ch->ch_bd->pci_dev,
 656                                         "Still flushing TX UART... i: %d\n", i);
 657                         udelay(10);
 658                 }
 659                 else
 660                         break;
 661         }
 662
 663         ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
 664 }
 665
 666
 667 /*
 668  * Flush the READ FIFO on the Neo.
 669  *
 670  * NOTE: Channel lock MUST be held before calling this function!
 671  */
 672 static void neo_flush_uart_read(struct jsm_channel *ch)
 673 {
 674         u8 tmp = 0;
 675         int i = 0;
 676
 677         if (!ch)
 678                 return;
 679
 680         writeb((UART_FCR_ENABLE_FIFO | UART_FCR_CLEAR_RCVR), &ch->ch_neo_uart->isr_fcr);
 681
 682         for (i = 0; i < 10; i++) {
 683
 684                 /* Check to see if the UART feels it completely flushed the FIFO. */
 685                 tmp = readb(&ch->ch_neo_uart->isr_fcr);
 686                 if (tmp & 2) {
 687                         jsm_printk(IOCTL, INFO, &ch->ch_bd->pci_dev,
 688                                         "Still flushing RX UART... i: %d\n", i);
 689                         udelay(10);
 690                 }
 691                 else
 692                         break;
 693         }
 694 }
 695
 696 /*
 697  * No locks are assumed to be held when calling this function.
 698  */
 699 static void neo_clear_break(struct jsm_channel *ch, int force)
 700 {
 701         unsigned long lock_flags;
 702
 703         spin_lock_irqsave(&ch->ch_lock, lock_flags);
 704
 705         /* Turn break off, and unset some variables */
 706         if (ch->ch_flags & CH_BREAK_SENDING) {
 707                 u8 temp = readb(&ch->ch_neo_uart->lcr);
 708                 writeb((temp & ~UART_LCR_SBC), &ch->ch_neo_uart->lcr);
 709
 710                 ch->ch_flags &= ~(CH_BREAK_SENDING);
 711                 jsm_printk(IOCTL, INFO, &ch->ch_bd->pci_dev,
 712                                 "clear break Finishing UART_LCR_SBC! finished: %lx\n", jiffies);
 713
 714                 /* flush write operation */
 715                 neo_pci_posting_flush(ch->ch_bd);
 716         }
 717         spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
 718 }
 719
 720 /*
 721  * Parse the ISR register.
 722  */
 723 static inline void neo_parse_isr(struct jsm_board *brd, u32 port)
 724 {
 725         struct jsm_channel *ch;
 726         u8 isr;
 727         u8 cause;
 728         unsigned long lock_flags;
 729
 730         if (!brd)
 731                 return;
 732
 733         if (port > brd->maxports)
 734                 return;
 735
 736         ch = brd->channels[port];
 737         if (!ch)
 738                 return;
 739
 740         /* Here we try to figure out what caused the interrupt to happen */
 741         while (1) {
 742
 743                 isr = readb(&ch->ch_neo_uart->isr_fcr);
 744
 745                 /* Bail if no pending interrupt */
 746                 if (isr & UART_IIR_NO_INT)
 747                         break;
 748
 749                 /*
 750                  * Yank off the upper 2 bits, which just show that the FIFO's are enabled.
 751                  */
 752                 isr &= ~(UART_17158_IIR_FIFO_ENABLED);
 753
 754                 jsm_printk(INTR, INFO, &ch->ch_bd->pci_dev,
 755                                 "%s:%d isr: %x\n", __FILE__, __LINE__, isr);
 756
 757                 if (isr & (UART_17158_IIR_RDI_TIMEOUT | UART_IIR_RDI)) {
 758                         /* Read data from uart -> queue */
 759                         neo_copy_data_from_uart_to_queue(ch);
 760
 761                         /* Call our tty layer to enforce queue flow control if needed. */
 762                         spin_lock_irqsave(&ch->ch_lock, lock_flags);
 763                         jsm_check_queue_flow_control(ch);
 764                         spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
 765                 }
 766
 767                 if (isr & UART_IIR_THRI) {
 768                         /* Transfer data (if any) from Write Queue -> UART. */
 769                         spin_lock_irqsave(&ch->ch_lock, lock_flags);
 770                         ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
 771                         spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
 772                         neo_copy_data_from_queue_to_uart(ch);
 773                 }
 774
 775                 if (isr & UART_17158_IIR_XONXOFF) {
 776                         cause = readb(&ch->ch_neo_uart->xoffchar1);
 777
 778                         jsm_printk(INTR, INFO, &ch->ch_bd->pci_dev,
 779                                         "Port %d. Got ISR_XONXOFF: cause:%x\n", port, cause);
 780
 781                         /*
 782                          * Since the UART detected either an XON or
 783                          * XOFF match, we need to figure out which
 784                          * one it was, so we can suspend or resume data flow.
 785                          */
 786                         spin_lock_irqsave(&ch->ch_lock, lock_flags);
 787                         if (cause == UART_17158_XON_DETECT) {
 788                                 /* Is output stopped right now, if so, resume it */
 789                                 if (brd->channels[port]->ch_flags & CH_STOP) {
 790                                         ch->ch_flags &= ~(CH_STOP);
 791                                 }
 792                                 jsm_printk(INTR, INFO, &ch->ch_bd->pci_dev,
 793                                                 "Port %d. XON detected in incoming data\n", port);
 794                         }
 795                         else if (cause == UART_17158_XOFF_DETECT) {
 796                                 if (!(brd->channels[port]->ch_flags & CH_STOP)) {
 797                                         ch->ch_flags |= CH_STOP;
 798                                         jsm_printk(INTR, INFO, &ch->ch_bd->pci_dev,
 799                                                         "Setting CH_STOP\n");
 800                                 }
 801                                 jsm_printk(INTR, INFO, &ch->ch_bd->pci_dev,
 802                                                 "Port: %d. XOFF detected in incoming data\n", port);
 803                         }
 804                         spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
 805                 }
 806
 807                 if (isr & UART_17158_IIR_HWFLOW_STATE_CHANGE) {
 808                         /*
 809                          * If we get here, this means the hardware is doing auto flow control.
 810                          * Check to see whether RTS/DTR or CTS/DSR caused this interrupt.
 811                          */
 812                         cause = readb(&ch->ch_neo_uart->mcr);
 813
 814                         /* Which pin is doing auto flow? RTS or DTR? */
 815                         spin_lock_irqsave(&ch->ch_lock, lock_flags);
 816                         if ((cause & 0x4) == 0) {
 817                                 if (cause & UART_MCR_RTS)
 818                                         ch->ch_mostat |= UART_MCR_RTS;
 819                                 else
 820                                         ch->ch_mostat &= ~(UART_MCR_RTS);
 821                         } else {
 822                                 if (cause & UART_MCR_DTR)
 823                                         ch->ch_mostat |= UART_MCR_DTR;
 824                                 else
 825                                         ch->ch_mostat &= ~(UART_MCR_DTR);
 826                         }
 827                         spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
 828                 }
 829
 830                 /* Parse any modem signal changes */
 831                 jsm_printk(INTR, INFO, &ch->ch_bd->pci_dev,
 832                                 "MOD_STAT: sending to parse_modem_sigs\n");
 833                 neo_parse_modem(ch, readb(&ch->ch_neo_uart->msr));
 834         }
 835 }
 836
 837 static inline void neo_parse_lsr(struct jsm_board *brd, u32 port)
 838 {
 839         struct jsm_channel *ch;
 840         int linestatus;
 841         unsigned long lock_flags;
 842
 843         if (!brd)
 844                 return;
 845
 846         if (port > brd->maxports)
 847                 return;
 848
 849         ch = brd->channels[port];
 850         if (!ch)
 851                 return;
 852
 853         linestatus = readb(&ch->ch_neo_uart->lsr);
 854
 855         jsm_printk(INTR, INFO, &ch->ch_bd->pci_dev,
 856                         "%s:%d port: %d linestatus: %x\n", __FILE__, __LINE__, port, linestatus);
 857
 858         ch->ch_cached_lsr |= linestatus;
 859
 860         if (ch->ch_cached_lsr & UART_LSR_DR) {
 861                 /* Read data from uart -> queue */
 862                 neo_copy_data_from_uart_to_queue(ch);
 863                 spin_lock_irqsave(&ch->ch_lock, lock_flags);
 864                 jsm_check_queue_flow_control(ch);
 865                 spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
 866         }
 867
 868         /*
 869          * This is a special flag. It indicates that at least 1
 870          * RX error (parity, framing, or break) has happened.
 871          * Mark this in our struct, which will tell me that I have
 872          *to do the special RX+LSR read for this FIFO load.
 873          */
 874         if (linestatus & UART_17158_RX_FIFO_DATA_ERROR)
 875                 jsm_printk(INTR, DEBUG, &ch->ch_bd->pci_dev,
 876                         "%s:%d Port: %d Got an RX error, need to parse LSR\n",
 877                         __FILE__, __LINE__, port);
 878
 879         /*
 880          * The next 3 tests should *NOT* happen, as the above test
 881          * should encapsulate all 3... At least, thats what Exar says.
 882          */
 883
 884         if (linestatus & UART_LSR_PE) {
 885                 ch->ch_err_parity++;
 886                 jsm_printk(INTR, DEBUG, &ch->ch_bd->pci_dev,
 887                         "%s:%d Port: %d. PAR ERR!\n", __FILE__, __LINE__, port);
 888         }
 889
 890         if (linestatus & UART_LSR_FE) {
 891                 ch->ch_err_frame++;
 892                 jsm_printk(INTR, DEBUG, &ch->ch_bd->pci_dev,
 893                         "%s:%d Port: %d. FRM ERR!\n", __FILE__, __LINE__, port);
 894         }
 895
 896         if (linestatus & UART_LSR_BI) {
 897                 ch->ch_err_break++;
 898                 jsm_printk(INTR, DEBUG, &ch->ch_bd->pci_dev,
 899                         "%s:%d Port: %d. BRK INTR!\n", __FILE__, __LINE__, port);
 900         }
 901
 902         if (linestatus & UART_LSR_OE) {
 903                 /*
 904                  * Rx Oruns. Exar says that an orun will NOT corrupt
 905                  * the FIFO. It will just replace the holding register
 906                  * with this new data byte. So basically just ignore this.
 907                  * Probably we should eventually have an orun stat in our driver...
 908                  */
 909                 ch->ch_err_overrun++;
 910                 jsm_printk(INTR, DEBUG, &ch->ch_bd->pci_dev,
 911                         "%s:%d Port: %d. Rx Overrun!\n", __FILE__, __LINE__, port);
 912         }
 913
 914         if (linestatus & UART_LSR_THRE) {
 915                 spin_lock_irqsave(&ch->ch_lock, lock_flags);
 916                 ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
 917                 spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
 918
 919                 /* Transfer data (if any) from Write Queue -> UART. */
 920                 neo_copy_data_from_queue_to_uart(ch);
 921         }
 922         else if (linestatus & UART_17158_TX_AND_FIFO_CLR) {
 923                 spin_lock_irqsave(&ch->ch_lock, lock_flags);
 924                 ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
 925                 spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
 926
 927                 /* Transfer data (if any) from Write Queue -> UART. */
 928                 neo_copy_data_from_queue_to_uart(ch);
 929         }
 930 }
 931
 932 /*
 933  * neo_param()
 934  * Send any/all changes to the line to the UART.
 935  */
 936 static void neo_param(struct jsm_channel *ch)
 937 {
 938         u8 lcr = 0;
 939         u8 uart_lcr = 0;
 940         u8 ier = 0;
 941         u32 baud = 9600;
 942         int quot = 0;
 943         struct jsm_board *bd;
 944
 945         bd = ch->ch_bd;
 946         if (!bd)
 947                 return;
 948
 949         /*
 950          * If baud rate is zero, flush queues, and set mval to drop DTR.
 951          */
 952         if ((ch->ch_c_cflag & (CBAUD)) == 0) {
 953                 ch->ch_r_head = ch->ch_r_tail = 0;
 954                 ch->ch_e_head = ch->ch_e_tail = 0;
 955                 ch->ch_w_head = ch->ch_w_tail = 0;
 956
 957                 neo_flush_uart_write(ch);
 958                 neo_flush_uart_read(ch);
 959
 960                 ch->ch_flags |= (CH_BAUD0);
 961                 ch->ch_mostat &= ~(UART_MCR_RTS | UART_MCR_DTR);
 962                 neo_assert_modem_signals(ch);
 963                 ch->ch_old_baud = 0;
 964                 return;
 965
 966         } else if (ch->ch_custom_speed) {
 967                         baud = ch->ch_custom_speed;
 968                         if (ch->ch_flags & CH_BAUD0)
 969                                 ch->ch_flags &= ~(CH_BAUD0);
 970         } else {
 971                 int i;
 972                 unsigned int cflag;
 973                 static struct {
 974                         unsigned int rate;
 975                         unsigned int cflag;
 976                 } baud_rates[] = {
 977                         { 921600, B921600 },
 978                         { 460800, B460800 },
 979                         { 230400, B230400 },
 980                         { 115200, B115200 },
 981                         {  57600, B57600  },
 982                         {  38400, B38400  },
 983                         {  19200, B19200  },
 984                         {   9600, B9600   },
 985                         {   4800, B4800   },
 986                         {   2400, B2400   },
 987                         {   1200, B1200   },
 988                         {    600, B600    },
 989                         {    300, B300    },
 990                         {    200, B200    },
 991                         {    150, B150    },
 992                         {    134, B134    },
 993                         {    110, B110    },
 994                         {     75, B75     },
 995                         {     50, B50     },
 996                 };
 997
 998                 cflag = C_BAUD(ch->uart_port.info->port.tty);
 999                 baud = 9600;
1000                 for (i = 0; i < ARRAY_SIZE(baud_rates); i++) {
1001                         if (baud_rates[i].cflag == cflag) {
1002                                 baud = baud_rates[i].rate;
1003                                 break;
1004                         }
1005                 }
1006
1007                 if (ch->ch_flags & CH_BAUD0)
1008                         ch->ch_flags &= ~(CH_BAUD0);
1009         }
1010
1011         if (ch->ch_c_cflag & PARENB)
1012                 lcr |= UART_LCR_PARITY;
1013
1014         if (!(ch->ch_c_cflag & PARODD))
1015                 lcr |= UART_LCR_EPAR;
1016
1017         /*
1018          * Not all platforms support mark/space parity,
1019          * so this will hide behind an ifdef.
1020          */
1021 #ifdef CMSPAR
1022         if (ch->ch_c_cflag & CMSPAR)
1023                 lcr |= UART_LCR_SPAR;
1024 #endif
1025
1026         if (ch->ch_c_cflag & CSTOPB)
1027                 lcr |= UART_LCR_STOP;
1028
1029         switch (ch->ch_c_cflag & CSIZE) {
1030                 case CS5:
1031                         lcr |= UART_LCR_WLEN5;
1032                         break;
1033                 case CS6:
1034                         lcr |= UART_LCR_WLEN6;
1035                         break;
1036                 case CS7:
1037                         lcr |= UART_LCR_WLEN7;
1038                         break;
1039                 case CS8:
1040                 default:
1041                         lcr |= UART_LCR_WLEN8;
1042                 break;
1043         }
1044
1045         ier = readb(&ch->ch_neo_uart->ier);
1046         uart_lcr = readb(&ch->ch_neo_uart->lcr);
1047
1048         if (baud == 0)
1049                 baud = 9600;
1050
1051         quot = ch->ch_bd->bd_dividend / baud;
1052
1053         if (quot != 0) {
1054                 ch->ch_old_baud = baud;
1055                 writeb(UART_LCR_DLAB, &ch->ch_neo_uart->lcr);
1056                 writeb((quot & 0xff), &ch->ch_neo_uart->txrx);
1057                 writeb((quot >> 8), &ch->ch_neo_uart->ier);
1058                 writeb(lcr, &ch->ch_neo_uart->lcr);
1059         }
1060
1061         if (uart_lcr != lcr)
1062                 writeb(lcr, &ch->ch_neo_uart->lcr);
1063
1064         if (ch->ch_c_cflag & CREAD)
1065                 ier |= (UART_IER_RDI | UART_IER_RLSI);
1066
1067         ier |= (UART_IER_THRI | UART_IER_MSI);
1068
1069         writeb(ier, &ch->ch_neo_uart->ier);
1070
1071         /* Set new start/stop chars */
1072         neo_set_new_start_stop_chars(ch);
1073
1074         if (ch->ch_c_cflag & CRTSCTS)
1075                 neo_set_cts_flow_control(ch);
1076         else if (ch->ch_c_iflag & IXON) {
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_output_flow_control(ch);
1080                 else
1081                         neo_set_ixon_flow_control(ch);
1082         }
1083         else
1084                 neo_set_no_output_flow_control(ch);
1085
1086         if (ch->ch_c_cflag & CRTSCTS)
1087                 neo_set_rts_flow_control(ch);
1088         else if (ch->ch_c_iflag & IXOFF) {
1089                 /* If start/stop is set to disable, then we should disable flow control */
1090                 if ((ch->ch_startc == __DISABLED_CHAR) || (ch->ch_stopc == __DISABLED_CHAR))
1091                         neo_set_no_input_flow_control(ch);
1092                 else
1093                         neo_set_ixoff_flow_control(ch);
1094         }
1095         else
1096                 neo_set_no_input_flow_control(ch);
1097         /*
1098          * Adjust the RX FIFO Trigger level if baud is less than 9600.
1099          * Not exactly elegant, but this is needed because of the Exar chip's
1100          * delay on firing off the RX FIFO interrupt on slower baud rates.
1101          */
1102         if (baud < 9600) {
1103                 writeb(1, &ch->ch_neo_uart->rfifo);
1104                 ch->ch_r_tlevel = 1;
1105         }
1106
1107         neo_assert_modem_signals(ch);
1108
1109         /* Get current status of the modem signals now */
1110         neo_parse_modem(ch, readb(&ch->ch_neo_uart->msr));
1111         return;
1112 }
1113
1114 /*
1115  * jsm_neo_intr()
1116  *
1117  * Neo specific interrupt handler.
1118  */
1119 static irqreturn_t neo_intr(int irq, void *voidbrd)
1120 {
1121         struct jsm_board *brd = voidbrd;
1122         struct jsm_channel *ch;
1123         int port = 0;
1124         int type = 0;
1125         int current_port;
1126         u32 tmp;
1127         u32 uart_poll;
1128         unsigned long lock_flags;
1129         unsigned long lock_flags2;
1130         int outofloop_count = 0;
1131
1132         brd->intr_count++;
1133
1134         /* Lock out the slow poller from running on this board. */
1135         spin_lock_irqsave(&brd->bd_intr_lock, lock_flags);
1136
1137         /*
1138          * Read in "extended" IRQ information from the 32bit Neo register.
1139          * Bits 0-7: What port triggered the interrupt.
1140          * Bits 8-31: Each 3bits indicate what type of interrupt occurred.
1141          */
1142         uart_poll = readl(brd->re_map_membase + UART_17158_POLL_ADDR_OFFSET);
1143
1144         jsm_printk(INTR, INFO, &brd->pci_dev,
1145                 "%s:%d uart_poll: %x\n", __FILE__, __LINE__, uart_poll);
1146
1147         if (!uart_poll) {
1148                 jsm_printk(INTR, INFO, &brd->pci_dev,
1149                         "Kernel interrupted to me, but no pending interrupts...\n");
1150                 spin_unlock_irqrestore(&brd->bd_intr_lock, lock_flags);
1151                 return IRQ_NONE;
1152         }
1153
1154         /* At this point, we have at least SOMETHING to service, dig further... */
1155
1156         current_port = 0;
1157
1158         /* Loop on each port */
1159         while (((uart_poll & 0xff) != 0) && (outofloop_count < 0xff)){
1160
1161                 tmp = uart_poll;
1162                 outofloop_count++;
1163
1164                 /* Check current port to see if it has interrupt pending */
1165                 if ((tmp & jsm_offset_table[current_port]) != 0) {
1166                         port = current_port;
1167                         type = tmp >> (8 + (port * 3));
1168                         type &= 0x7;
1169                 } else {
1170                         current_port++;
1171                         continue;
1172                 }
1173
1174                 jsm_printk(INTR, INFO, &brd->pci_dev,
1175                 "%s:%d port: %x type: %x\n", __FILE__, __LINE__, port, type);
1176
1177                 /* Remove this port + type from uart_poll */
1178                 uart_poll &= ~(jsm_offset_table[port]);
1179
1180                 if (!type) {
1181                         /* If no type, just ignore it, and move onto next port */
1182                         jsm_printk(INTR, ERR, &brd->pci_dev,
1183                                 "Interrupt with no type! port: %d\n", port);
1184                         continue;
1185                 }
1186
1187                 /* Switch on type of interrupt we have */
1188                 switch (type) {
1189
1190                 case UART_17158_RXRDY_TIMEOUT:
1191                         /*
1192                          * RXRDY Time-out is cleared by reading data in the
1193                         * RX FIFO until it falls below the trigger level.
1194                          */
1195
1196                         /* Verify the port is in range. */
1197                         if (port > brd->nasync)
1198                                 continue;
1199
1200                         ch = brd->channels[port];
1201                         neo_copy_data_from_uart_to_queue(ch);
1202
1203                         /* Call our tty layer to enforce queue flow control if needed. */
1204                         spin_lock_irqsave(&ch->ch_lock, lock_flags2);
1205                         jsm_check_queue_flow_control(ch);
1206                         spin_unlock_irqrestore(&ch->ch_lock, lock_flags2);
1207
1208                         continue;
1209
1210                 case UART_17158_RX_LINE_STATUS:
1211                         /*
1212                          * RXRDY and RX LINE Status (logic OR of LSR[4:1])
1213                          */
1214                         neo_parse_lsr(brd, port);
1215                         continue;
1216
1217                 case UART_17158_TXRDY:
1218                         /*
1219                          * TXRDY interrupt clears after reading ISR register for the UART channel.
1220                          */
1221
1222                         /*
1223                          * Yes, this is odd...
1224                          * Why would I check EVERY possibility of type of
1225                          * interrupt, when we know its TXRDY???
1226                          * Becuz for some reason, even tho we got triggered for TXRDY,
1227                          * it seems to be occassionally wrong. Instead of TX, which
1228                          * it should be, I was getting things like RXDY too. Weird.
1229                          */
1230                         neo_parse_isr(brd, port);
1231                         continue;
1232
1233                 case UART_17158_MSR:
1234                         /*
1235                          * MSR or flow control was seen.
1236                          */
1237                         neo_parse_isr(brd, port);
1238                         continue;
1239
1240                 default:
1241                         /*
1242                          * The UART triggered us with a bogus interrupt type.
1243                          * It appears the Exar chip, when REALLY bogged down, will throw
1244                          * these once and awhile.
1245                          * Its harmless, just ignore it and move on.
1246                          */
1247                         jsm_printk(INTR, ERR, &brd->pci_dev,
1248                                 "%s:%d Unknown Interrupt type: %x\n", __FILE__, __LINE__, type);
1249                         continue;
1250                 }
1251         }
1252
1253         spin_unlock_irqrestore(&brd->bd_intr_lock, lock_flags);
1254
1255         jsm_printk(INTR, INFO, &brd->pci_dev, "finish.\n");
1256         return IRQ_HANDLED;
1257 }
1258
1259 /*
1260  * Neo specific way of turning off the receiver.
1261  * Used as a way to enforce queue flow control when in
1262  * hardware flow control mode.
1263  */
1264 static void neo_disable_receiver(struct jsm_channel *ch)
1265 {
1266         u8 tmp = readb(&ch->ch_neo_uart->ier);
1267         tmp &= ~(UART_IER_RDI);
1268         writeb(tmp, &ch->ch_neo_uart->ier);
1269
1270         /* flush write operation */
1271         neo_pci_posting_flush(ch->ch_bd);
1272 }
1273
1274
1275 /*
1276  * Neo specific way of turning on the receiver.
1277  * Used as a way to un-enforce queue flow control when in
1278  * hardware flow control mode.
1279  */
1280 static void neo_enable_receiver(struct jsm_channel *ch)
1281 {
1282         u8 tmp = readb(&ch->ch_neo_uart->ier);
1283         tmp |= (UART_IER_RDI);
1284         writeb(tmp, &ch->ch_neo_uart->ier);
1285
1286         /* flush write operation */
1287         neo_pci_posting_flush(ch->ch_bd);
1288 }
1289
1290 static void neo_send_start_character(struct jsm_channel *ch)
1291 {
1292         if (!ch)
1293                 return;
1294
1295         if (ch->ch_startc != __DISABLED_CHAR) {
1296                 ch->ch_xon_sends++;
1297                 writeb(ch->ch_startc, &ch->ch_neo_uart->txrx);
1298
1299                 /* flush write operation */
1300                 neo_pci_posting_flush(ch->ch_bd);
1301         }
1302 }
1303
1304 static void neo_send_stop_character(struct jsm_channel *ch)
1305 {
1306         if (!ch)
1307                 return;
1308
1309         if (ch->ch_stopc != __DISABLED_CHAR) {
1310                 ch->ch_xoff_sends++;
1311                 writeb(ch->ch_stopc, &ch->ch_neo_uart->txrx);
1312
1313                 /* flush write operation */
1314                 neo_pci_posting_flush(ch->ch_bd);
1315         }
1316 }
1317
1318 /*
1319  * neo_uart_init
1320  */
1321 static void neo_uart_init(struct jsm_channel *ch)
1322 {
1323         writeb(0, &ch->ch_neo_uart->ier);
1324         writeb(0, &ch->ch_neo_uart->efr);
1325         writeb(UART_EFR_ECB, &ch->ch_neo_uart->efr);
1326
1327         /* Clear out UART and FIFO */
1328         readb(&ch->ch_neo_uart->txrx);
1329         writeb((UART_FCR_ENABLE_FIFO|UART_FCR_CLEAR_RCVR|UART_FCR_CLEAR_XMIT), &ch->ch_neo_uart->isr_fcr);
1330         readb(&ch->ch_neo_uart->lsr);
1331         readb(&ch->ch_neo_uart->msr);
1332
1333         ch->ch_flags |= CH_FIFO_ENABLED;
1334
1335         /* Assert any signals we want up */
1336         writeb(ch->ch_mostat, &ch->ch_neo_uart->mcr);
1337 }
1338
1339 /*
1340  * Make the UART completely turn off.
1341  */
1342 static void neo_uart_off(struct jsm_channel *ch)
1343 {
1344         /* Turn off UART enhanced bits */
1345         writeb(0, &ch->ch_neo_uart->efr);
1346
1347         /* Stop all interrupts from occurring. */
1348         writeb(0, &ch->ch_neo_uart->ier);
1349 }
1350
1351 static u32 neo_get_uart_bytes_left(struct jsm_channel *ch)
1352 {
1353         u8 left = 0;
1354         u8 lsr = readb(&ch->ch_neo_uart->lsr);
1355
1356         /* We must cache the LSR as some of the bits get reset once read... */
1357         ch->ch_cached_lsr |= lsr;
1358
1359         /* Determine whether the Transmitter is empty or not */
1360         if (!(lsr & UART_LSR_TEMT))
1361                 left = 1;
1362         else {
1363                 ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
1364                 left = 0;
1365         }
1366
1367         return left;
1368 }
1369
1370 /* Channel lock MUST be held by the calling function! */
1371 static void neo_send_break(struct jsm_channel *ch)
1372 {
1373         /*
1374          * Set the time we should stop sending the break.
1375          * If we are already sending a break, toss away the existing
1376          * time to stop, and use this new value instead.
1377          */
1378
1379         /* Tell the UART to start sending the break */
1380         if (!(ch->ch_flags & CH_BREAK_SENDING)) {
1381                 u8 temp = readb(&ch->ch_neo_uart->lcr);
1382                 writeb((temp | UART_LCR_SBC), &ch->ch_neo_uart->lcr);
1383                 ch->ch_flags |= (CH_BREAK_SENDING);
1384
1385                 /* flush write operation */
1386                 neo_pci_posting_flush(ch->ch_bd);
1387         }
1388 }
1389
1390 /*
1391  * neo_send_immediate_char.
1392  *
1393  * Sends a specific character as soon as possible to the UART,
1394  * jumping over any bytes that might be in the write queue.
1395  *
1396  * The channel lock MUST be held by the calling function.
1397  */
1398 static void neo_send_immediate_char(struct jsm_channel *ch, unsigned char c)
1399 {
1400         if (!ch)
1401                 return;
1402
1403         writeb(c, &ch->ch_neo_uart->txrx);
1404
1405         /* flush write operation */
1406         neo_pci_posting_flush(ch->ch_bd);
1407 }
1408
1409 struct board_ops jsm_neo_ops = {
1410         .intr                           = neo_intr,
1411         .uart_init                      = neo_uart_init,
1412         .uart_off                       = neo_uart_off,
1413         .param                          = neo_param,
1414         .assert_modem_signals           = neo_assert_modem_signals,
1415         .flush_uart_write               = neo_flush_uart_write,
1416         .flush_uart_read                = neo_flush_uart_read,
1417         .disable_receiver               = neo_disable_receiver,
1418         .enable_receiver                = neo_enable_receiver,
1419         .send_break                     = neo_send_break,
1420         .clear_break                    = neo_clear_break,
1421         .send_start_character           = neo_send_start_character,
1422         .send_stop_character            = neo_send_stop_character,
1423         .copy_data_from_queue_to_uart   = neo_copy_data_from_queue_to_uart,
1424         .get_uart_bytes_left            = neo_get_uart_bytes_left,
1425         .send_immediate_char            = neo_send_immediate_char
1426 };