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v6.8
   1// SPDX-License-Identifier: GPL-2.0+
   2/************************************************************************
   3 * Copyright 2003 Digi International (www.digi.com)
   4 *
   5 * Copyright (C) 2004 IBM Corporation. All rights reserved.
   6 *
 
 
 
 
 
 
 
 
 
 
   7 * Contact Information:
   8 * Scott H Kilau <Scott_Kilau@digi.com>
   9 * Wendy Xiong   <wendyx@us.ibm.com>
  10 *
  11 ***********************************************************************/
  12#include <linux/delay.h>	/* For udelay */
  13#include <linux/serial_reg.h>	/* For the various UART offsets */
  14#include <linux/tty.h>
  15#include <linux/pci.h>
  16#include <asm/io.h>
  17
  18#include "jsm.h"		/* Driver main header file */
  19
  20static u32 jsm_offset_table[8] = { 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80 };
  21
  22/*
  23 * This function allows calls to ensure that all outstanding
  24 * PCI writes have been completed, by doing a PCI read against
  25 * a non-destructive, read-only location on the Neo card.
  26 *
  27 * In this case, we are reading the DVID (Read-only Device Identification)
  28 * value of the Neo card.
  29 */
  30static inline void neo_pci_posting_flush(struct jsm_board *bd)
  31{
  32      readb(bd->re_map_membase + 0x8D);
  33}
  34
  35static void neo_set_cts_flow_control(struct jsm_channel *ch)
  36{
  37	u8 ier, efr;
  38	ier = readb(&ch->ch_neo_uart->ier);
  39	efr = readb(&ch->ch_neo_uart->efr);
  40
  41	jsm_dbg(PARAM, &ch->ch_bd->pci_dev, "Setting CTSFLOW\n");
  42
  43	/* Turn on auto CTS flow control */
  44	ier |= (UART_17158_IER_CTSDSR);
  45	efr |= (UART_17158_EFR_ECB | UART_17158_EFR_CTSDSR);
  46
  47	/* Turn off auto Xon flow control */
  48	efr &= ~(UART_17158_EFR_IXON);
  49
  50	/* Why? Becuz Exar's spec says we have to zero it out before setting it */
  51	writeb(0, &ch->ch_neo_uart->efr);
  52
  53	/* Turn on UART enhanced bits */
  54	writeb(efr, &ch->ch_neo_uart->efr);
  55
  56	/* Turn on table D, with 8 char hi/low watermarks */
  57	writeb((UART_17158_FCTR_TRGD | UART_17158_FCTR_RTS_4DELAY), &ch->ch_neo_uart->fctr);
  58
  59	/* Feed the UART our trigger levels */
  60	writeb(8, &ch->ch_neo_uart->tfifo);
  61	ch->ch_t_tlevel = 8;
  62
  63	writeb(ier, &ch->ch_neo_uart->ier);
  64}
  65
  66static void neo_set_rts_flow_control(struct jsm_channel *ch)
  67{
  68	u8 ier, efr;
  69	ier = readb(&ch->ch_neo_uart->ier);
  70	efr = readb(&ch->ch_neo_uart->efr);
  71
  72	jsm_dbg(PARAM, &ch->ch_bd->pci_dev, "Setting RTSFLOW\n");
  73
  74	/* Turn on auto RTS flow control */
  75	ier |= (UART_17158_IER_RTSDTR);
  76	efr |= (UART_17158_EFR_ECB | UART_17158_EFR_RTSDTR);
  77
  78	/* Turn off auto Xoff flow control */
  79	ier &= ~(UART_17158_IER_XOFF);
  80	efr &= ~(UART_17158_EFR_IXOFF);
  81
  82	/* Why? Becuz Exar's spec says we have to zero it out before setting it */
  83	writeb(0, &ch->ch_neo_uart->efr);
  84
  85	/* Turn on UART enhanced bits */
  86	writeb(efr, &ch->ch_neo_uart->efr);
  87
  88	writeb((UART_17158_FCTR_TRGD | UART_17158_FCTR_RTS_4DELAY), &ch->ch_neo_uart->fctr);
  89	ch->ch_r_watermark = 4;
  90
  91	writeb(56, &ch->ch_neo_uart->rfifo);
  92	ch->ch_r_tlevel = 56;
  93
  94	writeb(ier, &ch->ch_neo_uart->ier);
  95
  96	/*
  97	 * From the Neo UART spec sheet:
  98	 * The auto RTS/DTR function must be started by asserting
  99	 * RTS/DTR# output pin (MCR bit-0 or 1 to logic 1 after
 100	 * it is enabled.
 101	 */
 102	ch->ch_mostat |= (UART_MCR_RTS);
 103}
 104
 105
 106static void neo_set_ixon_flow_control(struct jsm_channel *ch)
 107{
 108	u8 ier, efr;
 109	ier = readb(&ch->ch_neo_uart->ier);
 110	efr = readb(&ch->ch_neo_uart->efr);
 111
 112	jsm_dbg(PARAM, &ch->ch_bd->pci_dev, "Setting IXON FLOW\n");
 113
 114	/* Turn off auto CTS flow control */
 115	ier &= ~(UART_17158_IER_CTSDSR);
 116	efr &= ~(UART_17158_EFR_CTSDSR);
 117
 118	/* Turn on auto Xon flow control */
 119	efr |= (UART_17158_EFR_ECB | UART_17158_EFR_IXON);
 120
 121	/* Why? Becuz Exar's spec says we have to zero it out before setting it */
 122	writeb(0, &ch->ch_neo_uart->efr);
 123
 124	/* Turn on UART enhanced bits */
 125	writeb(efr, &ch->ch_neo_uart->efr);
 126
 127	writeb((UART_17158_FCTR_TRGD | UART_17158_FCTR_RTS_8DELAY), &ch->ch_neo_uart->fctr);
 128	ch->ch_r_watermark = 4;
 129
 130	writeb(32, &ch->ch_neo_uart->rfifo);
 131	ch->ch_r_tlevel = 32;
 132
 133	/* Tell UART what start/stop chars it should be looking for */
 134	writeb(ch->ch_startc, &ch->ch_neo_uart->xonchar1);
 135	writeb(0, &ch->ch_neo_uart->xonchar2);
 136
 137	writeb(ch->ch_stopc, &ch->ch_neo_uart->xoffchar1);
 138	writeb(0, &ch->ch_neo_uart->xoffchar2);
 139
 140	writeb(ier, &ch->ch_neo_uart->ier);
 141}
 142
 143static void neo_set_ixoff_flow_control(struct jsm_channel *ch)
 144{
 145	u8 ier, efr;
 146	ier = readb(&ch->ch_neo_uart->ier);
 147	efr = readb(&ch->ch_neo_uart->efr);
 148
 149	jsm_dbg(PARAM, &ch->ch_bd->pci_dev, "Setting IXOFF FLOW\n");
 150
 151	/* Turn off auto RTS flow control */
 152	ier &= ~(UART_17158_IER_RTSDTR);
 153	efr &= ~(UART_17158_EFR_RTSDTR);
 154
 155	/* Turn on auto Xoff flow control */
 156	ier |= (UART_17158_IER_XOFF);
 157	efr |= (UART_17158_EFR_ECB | UART_17158_EFR_IXOFF);
 158
 159	/* Why? Becuz Exar's spec says we have to zero it out before setting it */
 160	writeb(0, &ch->ch_neo_uart->efr);
 161
 162	/* Turn on UART enhanced bits */
 163	writeb(efr, &ch->ch_neo_uart->efr);
 164
 165	/* Turn on table D, with 8 char hi/low watermarks */
 166	writeb((UART_17158_FCTR_TRGD | UART_17158_FCTR_RTS_8DELAY), &ch->ch_neo_uart->fctr);
 167
 168	writeb(8, &ch->ch_neo_uart->tfifo);
 169	ch->ch_t_tlevel = 8;
 170
 171	/* Tell UART what start/stop chars it should be looking for */
 172	writeb(ch->ch_startc, &ch->ch_neo_uart->xonchar1);
 173	writeb(0, &ch->ch_neo_uart->xonchar2);
 174
 175	writeb(ch->ch_stopc, &ch->ch_neo_uart->xoffchar1);
 176	writeb(0, &ch->ch_neo_uart->xoffchar2);
 177
 178	writeb(ier, &ch->ch_neo_uart->ier);
 179}
 180
 181static void neo_set_no_input_flow_control(struct jsm_channel *ch)
 182{
 183	u8 ier, efr;
 184	ier = readb(&ch->ch_neo_uart->ier);
 185	efr = readb(&ch->ch_neo_uart->efr);
 186
 187	jsm_dbg(PARAM, &ch->ch_bd->pci_dev, "Unsetting Input FLOW\n");
 188
 189	/* Turn off auto RTS flow control */
 190	ier &= ~(UART_17158_IER_RTSDTR);
 191	efr &= ~(UART_17158_EFR_RTSDTR);
 192
 193	/* Turn off auto Xoff flow control */
 194	ier &= ~(UART_17158_IER_XOFF);
 195	if (ch->ch_c_iflag & IXON)
 196		efr &= ~(UART_17158_EFR_IXOFF);
 197	else
 198		efr &= ~(UART_17158_EFR_ECB | UART_17158_EFR_IXOFF);
 199
 200	/* Why? Becuz Exar's spec says we have to zero it out before setting it */
 201	writeb(0, &ch->ch_neo_uart->efr);
 202
 203	/* Turn on UART enhanced bits */
 204	writeb(efr, &ch->ch_neo_uart->efr);
 205
 206	/* Turn on table D, with 8 char hi/low watermarks */
 207	writeb((UART_17158_FCTR_TRGD | UART_17158_FCTR_RTS_8DELAY), &ch->ch_neo_uart->fctr);
 208
 209	ch->ch_r_watermark = 0;
 210
 211	writeb(16, &ch->ch_neo_uart->tfifo);
 212	ch->ch_t_tlevel = 16;
 213
 214	writeb(16, &ch->ch_neo_uart->rfifo);
 215	ch->ch_r_tlevel = 16;
 216
 217	writeb(ier, &ch->ch_neo_uart->ier);
 218}
 219
 220static void neo_set_no_output_flow_control(struct jsm_channel *ch)
 221{
 222	u8 ier, efr;
 223	ier = readb(&ch->ch_neo_uart->ier);
 224	efr = readb(&ch->ch_neo_uart->efr);
 225
 226	jsm_dbg(PARAM, &ch->ch_bd->pci_dev, "Unsetting Output FLOW\n");
 227
 228	/* Turn off auto CTS flow control */
 229	ier &= ~(UART_17158_IER_CTSDSR);
 230	efr &= ~(UART_17158_EFR_CTSDSR);
 231
 232	/* Turn off auto Xon flow control */
 233	if (ch->ch_c_iflag & IXOFF)
 234		efr &= ~(UART_17158_EFR_IXON);
 235	else
 236		efr &= ~(UART_17158_EFR_ECB | UART_17158_EFR_IXON);
 237
 238	/* Why? Becuz Exar's spec says we have to zero it out before setting it */
 239	writeb(0, &ch->ch_neo_uart->efr);
 240
 241	/* Turn on UART enhanced bits */
 242	writeb(efr, &ch->ch_neo_uart->efr);
 243
 244	/* Turn on table D, with 8 char hi/low watermarks */
 245	writeb((UART_17158_FCTR_TRGD | UART_17158_FCTR_RTS_8DELAY), &ch->ch_neo_uart->fctr);
 246
 247	ch->ch_r_watermark = 0;
 248
 249	writeb(16, &ch->ch_neo_uart->tfifo);
 250	ch->ch_t_tlevel = 16;
 251
 252	writeb(16, &ch->ch_neo_uart->rfifo);
 253	ch->ch_r_tlevel = 16;
 254
 255	writeb(ier, &ch->ch_neo_uart->ier);
 256}
 257
 258static inline void neo_set_new_start_stop_chars(struct jsm_channel *ch)
 259{
 260
 261	/* if hardware flow control is set, then skip this whole thing */
 262	if (ch->ch_c_cflag & CRTSCTS)
 263		return;
 264
 265	jsm_dbg(PARAM, &ch->ch_bd->pci_dev, "start\n");
 266
 267	/* Tell UART what start/stop chars it should be looking for */
 268	writeb(ch->ch_startc, &ch->ch_neo_uart->xonchar1);
 269	writeb(0, &ch->ch_neo_uart->xonchar2);
 270
 271	writeb(ch->ch_stopc, &ch->ch_neo_uart->xoffchar1);
 272	writeb(0, &ch->ch_neo_uart->xoffchar2);
 273}
 274
 275static void neo_copy_data_from_uart_to_queue(struct jsm_channel *ch)
 276{
 277	int qleft = 0;
 278	u8 linestatus = 0;
 279	u8 error_mask = 0;
 280	int n = 0;
 281	int total = 0;
 282	u16 head;
 283	u16 tail;
 284
 
 
 
 285	/* cache head and tail of queue */
 286	head = ch->ch_r_head & RQUEUEMASK;
 287	tail = ch->ch_r_tail & RQUEUEMASK;
 288
 289	/* Get our cached LSR */
 290	linestatus = ch->ch_cached_lsr;
 291	ch->ch_cached_lsr = 0;
 292
 293	/* Store how much space we have left in the queue */
 294	qleft = tail - head - 1;
 295	if (qleft < 0)
 296		qleft += RQUEUEMASK + 1;
 297
 298	/*
 299	 * If the UART is not in FIFO mode, force the FIFO copy to
 300	 * NOT be run, by setting total to 0.
 301	 *
 302	 * On the other hand, if the UART IS in FIFO mode, then ask
 303	 * the UART to give us an approximation of data it has RX'ed.
 304	 */
 305	if (!(ch->ch_flags & CH_FIFO_ENABLED))
 306		total = 0;
 307	else {
 308		total = readb(&ch->ch_neo_uart->rfifo);
 309
 310		/*
 311		 * EXAR chip bug - RX FIFO COUNT - Fudge factor.
 312		 *
 313		 * This resolves a problem/bug with the Exar chip that sometimes
 314		 * returns a bogus value in the rfifo register.
 315		 * The count can be any where from 0-3 bytes "off".
 316		 * Bizarre, but true.
 317		 */
 318		total -= 3;
 319	}
 320
 321	/*
 322	 * Finally, bound the copy to make sure we don't overflow
 323	 * our own queue...
 324	 * The byte by byte copy loop below this loop this will
 325	 * deal with the queue overflow possibility.
 326	 */
 327	total = min(total, qleft);
 328
 329	while (total > 0) {
 330		/*
 331		 * Grab the linestatus register, we need to check
 332		 * to see if there are any errors in the FIFO.
 333		 */
 334		linestatus = readb(&ch->ch_neo_uart->lsr);
 335
 336		/*
 337		 * Break out if there is a FIFO error somewhere.
 338		 * This will allow us to go byte by byte down below,
 339		 * finding the exact location of the error.
 340		 */
 341		if (linestatus & UART_17158_RX_FIFO_DATA_ERROR)
 342			break;
 343
 344		/* Make sure we don't go over the end of our queue */
 345		n = min(((u32) total), (RQUEUESIZE - (u32) head));
 346
 347		/*
 348		 * Cut down n even further if needed, this is to fix
 349		 * a problem with memcpy_fromio() with the Neo on the
 350		 * IBM pSeries platform.
 351		 * 15 bytes max appears to be the magic number.
 352		 */
 353		n = min((u32) n, (u32) 12);
 354
 355		/*
 356		 * Since we are grabbing the linestatus register, which
 357		 * will reset some bits after our read, we need to ensure
 358		 * we don't miss our TX FIFO emptys.
 359		 */
 360		if (linestatus & (UART_LSR_THRE | UART_17158_TX_AND_FIFO_CLR))
 361			ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
 362
 363		linestatus = 0;
 364
 365		/* Copy data from uart to the queue */
 366		memcpy_fromio(ch->ch_rqueue + head, &ch->ch_neo_uart->txrxburst, n);
 367		/*
 368		 * Since RX_FIFO_DATA_ERROR was 0, we are guaranteed
 369		 * that all the data currently in the FIFO is free of
 370		 * breaks and parity/frame/orun errors.
 371		 */
 372		memset(ch->ch_equeue + head, 0, n);
 373
 374		/* Add to and flip head if needed */
 375		head = (head + n) & RQUEUEMASK;
 376		total -= n;
 377		qleft -= n;
 378		ch->ch_rxcount += n;
 379	}
 380
 381	/*
 382	 * Create a mask to determine whether we should
 383	 * insert the character (if any) into our queue.
 384	 */
 385	if (ch->ch_c_iflag & IGNBRK)
 386		error_mask |= UART_LSR_BI;
 387
 388	/*
 389	 * Now cleanup any leftover bytes still in the UART.
 390	 * Also deal with any possible queue overflow here as well.
 391	 */
 392	while (1) {
 393
 394		/*
 395		 * Its possible we have a linestatus from the loop above
 396		 * this, so we "OR" on any extra bits.
 397		 */
 398		linestatus |= readb(&ch->ch_neo_uart->lsr);
 399
 400		/*
 401		 * If the chip tells us there is no more data pending to
 402		 * be read, we can then leave.
 403		 * But before we do, cache the linestatus, just in case.
 404		 */
 405		if (!(linestatus & UART_LSR_DR)) {
 406			ch->ch_cached_lsr = linestatus;
 407			break;
 408		}
 409
 410		/* No need to store this bit */
 411		linestatus &= ~UART_LSR_DR;
 412
 413		/*
 414		 * Since we are grabbing the linestatus register, which
 415		 * will reset some bits after our read, we need to ensure
 416		 * we don't miss our TX FIFO emptys.
 417		 */
 418		if (linestatus & (UART_LSR_THRE | UART_17158_TX_AND_FIFO_CLR)) {
 419			linestatus &= ~(UART_LSR_THRE | UART_17158_TX_AND_FIFO_CLR);
 420			ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
 421		}
 422
 423		/*
 424		 * Discard character if we are ignoring the error mask.
 425		 */
 426		if (linestatus & error_mask) {
 427			u8 discard;
 428			linestatus = 0;
 429			memcpy_fromio(&discard, &ch->ch_neo_uart->txrxburst, 1);
 430			continue;
 431		}
 432
 433		/*
 434		 * If our queue is full, we have no choice but to drop some data.
 435		 * The assumption is that HWFLOW or SWFLOW should have stopped
 436		 * things way way before we got to this point.
 437		 *
 438		 * I decided that I wanted to ditch the oldest data first,
 439		 * I hope thats okay with everyone? Yes? Good.
 440		 */
 441		while (qleft < 1) {
 442			jsm_dbg(READ, &ch->ch_bd->pci_dev,
 443				"Queue full, dropping DATA:%x LSR:%x\n",
 444				ch->ch_rqueue[tail], ch->ch_equeue[tail]);
 445
 446			ch->ch_r_tail = tail = (tail + 1) & RQUEUEMASK;
 447			ch->ch_err_overrun++;
 448			qleft++;
 449		}
 450
 451		memcpy_fromio(ch->ch_rqueue + head, &ch->ch_neo_uart->txrxburst, 1);
 452		ch->ch_equeue[head] = (u8) linestatus;
 453
 454		jsm_dbg(READ, &ch->ch_bd->pci_dev, "DATA/LSR pair: %x %x\n",
 455			ch->ch_rqueue[head], ch->ch_equeue[head]);
 456
 457		/* Ditch any remaining linestatus value. */
 458		linestatus = 0;
 459
 460		/* Add to and flip head if needed */
 461		head = (head + 1) & RQUEUEMASK;
 462
 463		qleft--;
 464		ch->ch_rxcount++;
 465	}
 466
 467	/*
 468	 * Write new final heads to channel structure.
 469	 */
 470	ch->ch_r_head = head & RQUEUEMASK;
 471	ch->ch_e_head = head & EQUEUEMASK;
 472	jsm_input(ch);
 473}
 474
 475static void neo_copy_data_from_queue_to_uart(struct jsm_channel *ch)
 476{
 477	u16 head;
 478	u16 tail;
 479	int n;
 480	int s;
 481	int qlen;
 482	u32 len_written = 0;
 483	struct circ_buf *circ;
 484
 485	if (!ch)
 486		return;
 487
 488	circ = &ch->uart_port.state->xmit;
 489
 490	/* No data to write to the UART */
 491	if (uart_circ_empty(circ))
 492		return;
 493
 494	/* If port is "stopped", don't send any data to the UART */
 495	if ((ch->ch_flags & CH_STOP) || (ch->ch_flags & CH_BREAK_SENDING))
 496		return;
 497	/*
 498	 * If FIFOs are disabled. Send data directly to txrx register
 499	 */
 500	if (!(ch->ch_flags & CH_FIFO_ENABLED)) {
 501		u8 lsrbits = readb(&ch->ch_neo_uart->lsr);
 502
 503		ch->ch_cached_lsr |= lsrbits;
 504		if (ch->ch_cached_lsr & UART_LSR_THRE) {
 505			ch->ch_cached_lsr &= ~(UART_LSR_THRE);
 506
 507			writeb(circ->buf[circ->tail], &ch->ch_neo_uart->txrx);
 508			jsm_dbg(WRITE, &ch->ch_bd->pci_dev,
 509				"Tx data: %x\n", circ->buf[circ->tail]);
 510			circ->tail = (circ->tail + 1) & (UART_XMIT_SIZE - 1);
 511			ch->ch_txcount++;
 512		}
 513		return;
 514	}
 515
 516	/*
 517	 * We have to do it this way, because of the EXAR TXFIFO count bug.
 518	 */
 519	if (!(ch->ch_flags & (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM)))
 520		return;
 521
 522	n = UART_17158_TX_FIFOSIZE - ch->ch_t_tlevel;
 523
 524	/* cache head and tail of queue */
 525	head = circ->head & (UART_XMIT_SIZE - 1);
 526	tail = circ->tail & (UART_XMIT_SIZE - 1);
 527	qlen = uart_circ_chars_pending(circ);
 528
 529	/* Find minimum of the FIFO space, versus queue length */
 530	n = min(n, qlen);
 531
 532	while (n > 0) {
 533
 534		s = ((head >= tail) ? head : UART_XMIT_SIZE) - tail;
 535		s = min(s, n);
 536
 537		if (s <= 0)
 538			break;
 539
 540		memcpy_toio(&ch->ch_neo_uart->txrxburst, circ->buf + tail, s);
 541		/* Add and flip queue if needed */
 542		tail = (tail + s) & (UART_XMIT_SIZE - 1);
 543		n -= s;
 544		ch->ch_txcount += s;
 545		len_written += s;
 546	}
 547
 548	/* Update the final tail */
 549	circ->tail = tail & (UART_XMIT_SIZE - 1);
 550
 551	if (len_written >= ch->ch_t_tlevel)
 552		ch->ch_flags &= ~(CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
 553
 554	if (uart_circ_empty(circ))
 555		uart_write_wakeup(&ch->uart_port);
 556}
 557
 558static void neo_parse_modem(struct jsm_channel *ch, u8 signals)
 559{
 560	u8 msignals = signals;
 561
 562	jsm_dbg(MSIGS, &ch->ch_bd->pci_dev,
 563		"neo_parse_modem: port: %d msignals: %x\n",
 564		ch->ch_portnum, msignals);
 565
 566	/* Scrub off lower bits. They signify delta's, which I don't care about */
 567	/* Keep DDCD and DDSR though */
 568	msignals &= 0xf8;
 569
 570	if (msignals & UART_MSR_DDCD)
 571		uart_handle_dcd_change(&ch->uart_port, msignals & UART_MSR_DCD);
 572	if (msignals & UART_MSR_DDSR)
 573		uart_handle_cts_change(&ch->uart_port, msignals & UART_MSR_CTS);
 574	if (msignals & UART_MSR_DCD)
 575		ch->ch_mistat |= UART_MSR_DCD;
 576	else
 577		ch->ch_mistat &= ~UART_MSR_DCD;
 578
 579	if (msignals & UART_MSR_DSR)
 580		ch->ch_mistat |= UART_MSR_DSR;
 581	else
 582		ch->ch_mistat &= ~UART_MSR_DSR;
 583
 584	if (msignals & UART_MSR_RI)
 585		ch->ch_mistat |= UART_MSR_RI;
 586	else
 587		ch->ch_mistat &= ~UART_MSR_RI;
 588
 589	if (msignals & UART_MSR_CTS)
 590		ch->ch_mistat |= UART_MSR_CTS;
 591	else
 592		ch->ch_mistat &= ~UART_MSR_CTS;
 593
 594	jsm_dbg(MSIGS, &ch->ch_bd->pci_dev,
 595		"Port: %d DTR: %d RTS: %d CTS: %d DSR: %d " "RI: %d CD: %d\n",
 596		ch->ch_portnum,
 597		!!((ch->ch_mistat | ch->ch_mostat) & UART_MCR_DTR),
 598		!!((ch->ch_mistat | ch->ch_mostat) & UART_MCR_RTS),
 599		!!((ch->ch_mistat | ch->ch_mostat) & UART_MSR_CTS),
 600		!!((ch->ch_mistat | ch->ch_mostat) & UART_MSR_DSR),
 601		!!((ch->ch_mistat | ch->ch_mostat) & UART_MSR_RI),
 602		!!((ch->ch_mistat | ch->ch_mostat) & UART_MSR_DCD));
 603}
 604
 605/* Make the UART raise any of the output signals we want up */
 606static void neo_assert_modem_signals(struct jsm_channel *ch)
 607{
 608	if (!ch)
 609		return;
 610
 611	writeb(ch->ch_mostat, &ch->ch_neo_uart->mcr);
 612
 613	/* flush write operation */
 614	neo_pci_posting_flush(ch->ch_bd);
 615}
 616
 617/*
 618 * Flush the WRITE FIFO on the Neo.
 619 *
 620 * NOTE: Channel lock MUST be held before calling this function!
 621 */
 622static void neo_flush_uart_write(struct jsm_channel *ch)
 623{
 624	u8 tmp = 0;
 625	int i = 0;
 626
 627	if (!ch)
 628		return;
 629
 630	writeb((UART_FCR_ENABLE_FIFO | UART_FCR_CLEAR_XMIT), &ch->ch_neo_uart->isr_fcr);
 631
 632	for (i = 0; i < 10; i++) {
 633
 634		/* Check to see if the UART feels it completely flushed the FIFO. */
 635		tmp = readb(&ch->ch_neo_uart->isr_fcr);
 636		if (tmp & UART_FCR_CLEAR_XMIT) {
 637			jsm_dbg(IOCTL, &ch->ch_bd->pci_dev,
 638				"Still flushing TX UART... i: %d\n", i);
 639			udelay(10);
 640		}
 641		else
 642			break;
 643	}
 644
 645	ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
 646}
 647
 648
 649/*
 650 * Flush the READ FIFO on the Neo.
 651 *
 652 * NOTE: Channel lock MUST be held before calling this function!
 653 */
 654static void neo_flush_uart_read(struct jsm_channel *ch)
 655{
 656	u8 tmp = 0;
 657	int i = 0;
 658
 659	if (!ch)
 660		return;
 661
 662	writeb((UART_FCR_ENABLE_FIFO | UART_FCR_CLEAR_RCVR), &ch->ch_neo_uart->isr_fcr);
 663
 664	for (i = 0; i < 10; i++) {
 665
 666		/* Check to see if the UART feels it completely flushed the FIFO. */
 667		tmp = readb(&ch->ch_neo_uart->isr_fcr);
 668		if (tmp & 2) {
 669			jsm_dbg(IOCTL, &ch->ch_bd->pci_dev,
 670				"Still flushing RX UART... i: %d\n", i);
 671			udelay(10);
 672		}
 673		else
 674			break;
 675	}
 676}
 677
 678/*
 679 * No locks are assumed to be held when calling this function.
 680 */
 681static void neo_clear_break(struct jsm_channel *ch)
 682{
 683	unsigned long lock_flags;
 684
 685	spin_lock_irqsave(&ch->ch_lock, lock_flags);
 686
 687	/* Turn break off, and unset some variables */
 688	if (ch->ch_flags & CH_BREAK_SENDING) {
 689		u8 temp = readb(&ch->ch_neo_uart->lcr);
 690		writeb((temp & ~UART_LCR_SBC), &ch->ch_neo_uart->lcr);
 691
 692		ch->ch_flags &= ~(CH_BREAK_SENDING);
 693		jsm_dbg(IOCTL, &ch->ch_bd->pci_dev,
 694			"clear break Finishing UART_LCR_SBC! finished: %lx\n",
 695			jiffies);
 696
 697		/* flush write operation */
 698		neo_pci_posting_flush(ch->ch_bd);
 699	}
 700	spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
 701}
 702
 703/*
 704 * Parse the ISR register.
 705 */
 706static void neo_parse_isr(struct jsm_board *brd, u32 port)
 707{
 708	struct jsm_channel *ch;
 709	u8 isr;
 710	u8 cause;
 711	unsigned long lock_flags;
 712
 713	if (!brd)
 714		return;
 715
 716	if (port >= brd->maxports)
 717		return;
 718
 719	ch = brd->channels[port];
 720	if (!ch)
 721		return;
 722
 723	/* Here we try to figure out what caused the interrupt to happen */
 724	while (1) {
 725
 726		isr = readb(&ch->ch_neo_uart->isr_fcr);
 727
 728		/* Bail if no pending interrupt */
 729		if (isr & UART_IIR_NO_INT)
 730			break;
 731
 732		/*
 733		 * Yank off the upper 2 bits, which just show that the FIFO's are enabled.
 734		 */
 735		isr &= ~(UART_17158_IIR_FIFO_ENABLED);
 736
 737		jsm_dbg(INTR, &ch->ch_bd->pci_dev, "%s:%d isr: %x\n",
 738			__FILE__, __LINE__, isr);
 739
 740		if (isr & (UART_17158_IIR_RDI_TIMEOUT | UART_IIR_RDI)) {
 741			/* Read data from uart -> queue */
 742			neo_copy_data_from_uart_to_queue(ch);
 743
 744			/* Call our tty layer to enforce queue flow control if needed. */
 745			spin_lock_irqsave(&ch->ch_lock, lock_flags);
 746			jsm_check_queue_flow_control(ch);
 747			spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
 748		}
 749
 750		if (isr & UART_IIR_THRI) {
 751			/* Transfer data (if any) from Write Queue -> UART. */
 752			spin_lock_irqsave(&ch->ch_lock, lock_flags);
 753			ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
 754			spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
 755			neo_copy_data_from_queue_to_uart(ch);
 756		}
 757
 758		if (isr & UART_17158_IIR_XONXOFF) {
 759			cause = readb(&ch->ch_neo_uart->xoffchar1);
 760
 761			jsm_dbg(INTR, &ch->ch_bd->pci_dev,
 762				"Port %d. Got ISR_XONXOFF: cause:%x\n",
 763				port, cause);
 764
 765			/*
 766			 * Since the UART detected either an XON or
 767			 * XOFF match, we need to figure out which
 768			 * one it was, so we can suspend or resume data flow.
 769			 */
 770			spin_lock_irqsave(&ch->ch_lock, lock_flags);
 771			if (cause == UART_17158_XON_DETECT) {
 772				/* Is output stopped right now, if so, resume it */
 773				if (brd->channels[port]->ch_flags & CH_STOP) {
 774					ch->ch_flags &= ~(CH_STOP);
 775				}
 776				jsm_dbg(INTR, &ch->ch_bd->pci_dev,
 777					"Port %d. XON detected in incoming data\n",
 778					port);
 779			}
 780			else if (cause == UART_17158_XOFF_DETECT) {
 781				if (!(brd->channels[port]->ch_flags & CH_STOP)) {
 782					ch->ch_flags |= CH_STOP;
 783					jsm_dbg(INTR, &ch->ch_bd->pci_dev,
 784						"Setting CH_STOP\n");
 785				}
 786				jsm_dbg(INTR, &ch->ch_bd->pci_dev,
 787					"Port: %d. XOFF detected in incoming data\n",
 788					port);
 789			}
 790			spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
 791		}
 792
 793		if (isr & UART_17158_IIR_HWFLOW_STATE_CHANGE) {
 794			/*
 795			 * If we get here, this means the hardware is doing auto flow control.
 796			 * Check to see whether RTS/DTR or CTS/DSR caused this interrupt.
 797			 */
 798			cause = readb(&ch->ch_neo_uart->mcr);
 799
 800			/* Which pin is doing auto flow? RTS or DTR? */
 801			spin_lock_irqsave(&ch->ch_lock, lock_flags);
 802			if ((cause & 0x4) == 0) {
 803				if (cause & UART_MCR_RTS)
 804					ch->ch_mostat |= UART_MCR_RTS;
 805				else
 806					ch->ch_mostat &= ~(UART_MCR_RTS);
 807			} else {
 808				if (cause & UART_MCR_DTR)
 809					ch->ch_mostat |= UART_MCR_DTR;
 810				else
 811					ch->ch_mostat &= ~(UART_MCR_DTR);
 812			}
 813			spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
 814		}
 815
 816		/* Parse any modem signal changes */
 817		jsm_dbg(INTR, &ch->ch_bd->pci_dev,
 818			"MOD_STAT: sending to parse_modem_sigs\n");
 819		uart_port_lock_irqsave(&ch->uart_port, &lock_flags);
 820		neo_parse_modem(ch, readb(&ch->ch_neo_uart->msr));
 821		uart_port_unlock_irqrestore(&ch->uart_port, lock_flags);
 822	}
 823}
 824
 825static inline void neo_parse_lsr(struct jsm_board *brd, u32 port)
 826{
 827	struct jsm_channel *ch;
 828	int linestatus;
 829	unsigned long lock_flags;
 830
 831	if (!brd)
 832		return;
 833
 834	if (port >= brd->maxports)
 835		return;
 836
 837	ch = brd->channels[port];
 838	if (!ch)
 839		return;
 840
 841	linestatus = readb(&ch->ch_neo_uart->lsr);
 842
 843	jsm_dbg(INTR, &ch->ch_bd->pci_dev, "%s:%d port: %d linestatus: %x\n",
 844		__FILE__, __LINE__, port, linestatus);
 845
 846	ch->ch_cached_lsr |= linestatus;
 847
 848	if (ch->ch_cached_lsr & UART_LSR_DR) {
 849		/* Read data from uart -> queue */
 850		neo_copy_data_from_uart_to_queue(ch);
 851		spin_lock_irqsave(&ch->ch_lock, lock_flags);
 852		jsm_check_queue_flow_control(ch);
 853		spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
 854	}
 855
 856	/*
 857	 * This is a special flag. It indicates that at least 1
 858	 * RX error (parity, framing, or break) has happened.
 859	 * Mark this in our struct, which will tell me that I have
 860	 *to do the special RX+LSR read for this FIFO load.
 861	 */
 862	if (linestatus & UART_17158_RX_FIFO_DATA_ERROR)
 863		jsm_dbg(INTR, &ch->ch_bd->pci_dev,
 864			"%s:%d Port: %d Got an RX error, need to parse LSR\n",
 865			__FILE__, __LINE__, port);
 866
 867	/*
 868	 * The next 3 tests should *NOT* happen, as the above test
 869	 * should encapsulate all 3... At least, thats what Exar says.
 870	 */
 871
 872	if (linestatus & UART_LSR_PE) {
 873		ch->ch_err_parity++;
 874		jsm_dbg(INTR, &ch->ch_bd->pci_dev, "%s:%d Port: %d. PAR ERR!\n",
 875			__FILE__, __LINE__, port);
 876	}
 877
 878	if (linestatus & UART_LSR_FE) {
 879		ch->ch_err_frame++;
 880		jsm_dbg(INTR, &ch->ch_bd->pci_dev, "%s:%d Port: %d. FRM ERR!\n",
 881			__FILE__, __LINE__, port);
 882	}
 883
 884	if (linestatus & UART_LSR_BI) {
 885		ch->ch_err_break++;
 886		jsm_dbg(INTR, &ch->ch_bd->pci_dev,
 887			"%s:%d Port: %d. BRK INTR!\n",
 888			__FILE__, __LINE__, port);
 889	}
 890
 891	if (linestatus & UART_LSR_OE) {
 892		/*
 893		 * Rx Oruns. Exar says that an orun will NOT corrupt
 894		 * the FIFO. It will just replace the holding register
 895		 * with this new data byte. So basically just ignore this.
 896		 * Probably we should eventually have an orun stat in our driver...
 897		 */
 898		ch->ch_err_overrun++;
 899		jsm_dbg(INTR, &ch->ch_bd->pci_dev,
 900			"%s:%d Port: %d. Rx Overrun!\n",
 901			__FILE__, __LINE__, port);
 902	}
 903
 904	if (linestatus & UART_LSR_THRE) {
 905		spin_lock_irqsave(&ch->ch_lock, lock_flags);
 906		ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
 907		spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
 908
 909		/* Transfer data (if any) from Write Queue -> UART. */
 910		neo_copy_data_from_queue_to_uart(ch);
 911	}
 912	else if (linestatus & UART_17158_TX_AND_FIFO_CLR) {
 913		spin_lock_irqsave(&ch->ch_lock, lock_flags);
 914		ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
 915		spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
 916
 917		/* Transfer data (if any) from Write Queue -> UART. */
 918		neo_copy_data_from_queue_to_uart(ch);
 919	}
 920}
 921
 922/*
 923 * neo_param()
 924 * Send any/all changes to the line to the UART.
 925 */
 926static void neo_param(struct jsm_channel *ch)
 927{
 928	u8 lcr = 0;
 929	u8 uart_lcr, ier;
 930	u32 baud;
 931	int quot;
 932	struct jsm_board *bd;
 933
 934	bd = ch->ch_bd;
 935	if (!bd)
 936		return;
 937
 938	/*
 939	 * If baud rate is zero, flush queues, and set mval to drop DTR.
 940	 */
 941	if ((ch->ch_c_cflag & CBAUD) == B0) {
 942		ch->ch_r_head = ch->ch_r_tail = 0;
 943		ch->ch_e_head = ch->ch_e_tail = 0;
 944
 945		neo_flush_uart_write(ch);
 946		neo_flush_uart_read(ch);
 947
 948		ch->ch_flags |= (CH_BAUD0);
 949		ch->ch_mostat &= ~(UART_MCR_RTS | UART_MCR_DTR);
 950		neo_assert_modem_signals(ch);
 951		return;
 952
 953	} else {
 954		int i;
 955		unsigned int cflag;
 956		static struct {
 957			unsigned int rate;
 958			unsigned int cflag;
 959		} baud_rates[] = {
 960			{ 921600, B921600 },
 961			{ 460800, B460800 },
 962			{ 230400, B230400 },
 963			{ 115200, B115200 },
 964			{  57600, B57600  },
 965			{  38400, B38400  },
 966			{  19200, B19200  },
 967			{   9600, B9600   },
 968			{   4800, B4800   },
 969			{   2400, B2400   },
 970			{   1200, B1200   },
 971			{    600, B600    },
 972			{    300, B300    },
 973			{    200, B200    },
 974			{    150, B150    },
 975			{    134, B134    },
 976			{    110, B110    },
 977			{     75, B75     },
 978			{     50, B50     },
 979		};
 980
 981		cflag = C_BAUD(ch->uart_port.state->port.tty);
 982		baud = 9600;
 983		for (i = 0; i < ARRAY_SIZE(baud_rates); i++) {
 984			if (baud_rates[i].cflag == cflag) {
 985				baud = baud_rates[i].rate;
 986				break;
 987			}
 988		}
 989
 990		if (ch->ch_flags & CH_BAUD0)
 991			ch->ch_flags &= ~(CH_BAUD0);
 992	}
 993
 994	if (ch->ch_c_cflag & PARENB)
 995		lcr |= UART_LCR_PARITY;
 996
 997	if (!(ch->ch_c_cflag & PARODD))
 998		lcr |= UART_LCR_EPAR;
 999
 
 
 
 
 
1000	if (ch->ch_c_cflag & CMSPAR)
1001		lcr |= UART_LCR_SPAR;
 
1002
1003	if (ch->ch_c_cflag & CSTOPB)
1004		lcr |= UART_LCR_STOP;
1005
1006	lcr |= UART_LCR_WLEN(tty_get_char_size(ch->ch_c_cflag));
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1007
1008	ier = readb(&ch->ch_neo_uart->ier);
1009	uart_lcr = readb(&ch->ch_neo_uart->lcr);
1010
1011	quot = ch->ch_bd->bd_dividend / baud;
1012
1013	if (quot != 0) {
1014		writeb(UART_LCR_DLAB, &ch->ch_neo_uart->lcr);
1015		writeb((quot & 0xff), &ch->ch_neo_uart->txrx);
1016		writeb((quot >> 8), &ch->ch_neo_uart->ier);
1017		writeb(lcr, &ch->ch_neo_uart->lcr);
1018	}
1019
1020	if (uart_lcr != lcr)
1021		writeb(lcr, &ch->ch_neo_uart->lcr);
1022
1023	if (ch->ch_c_cflag & CREAD)
1024		ier |= (UART_IER_RDI | UART_IER_RLSI);
1025
1026	ier |= (UART_IER_THRI | UART_IER_MSI);
1027
1028	writeb(ier, &ch->ch_neo_uart->ier);
1029
1030	/* Set new start/stop chars */
1031	neo_set_new_start_stop_chars(ch);
1032
1033	if (ch->ch_c_cflag & CRTSCTS)
1034		neo_set_cts_flow_control(ch);
1035	else if (ch->ch_c_iflag & IXON) {
1036		/* If start/stop is set to disable, then we should disable flow control */
1037		if ((ch->ch_startc == __DISABLED_CHAR) || (ch->ch_stopc == __DISABLED_CHAR))
1038			neo_set_no_output_flow_control(ch);
1039		else
1040			neo_set_ixon_flow_control(ch);
1041	}
1042	else
1043		neo_set_no_output_flow_control(ch);
1044
1045	if (ch->ch_c_cflag & CRTSCTS)
1046		neo_set_rts_flow_control(ch);
1047	else if (ch->ch_c_iflag & IXOFF) {
1048		/* If start/stop is set to disable, then we should disable flow control */
1049		if ((ch->ch_startc == __DISABLED_CHAR) || (ch->ch_stopc == __DISABLED_CHAR))
1050			neo_set_no_input_flow_control(ch);
1051		else
1052			neo_set_ixoff_flow_control(ch);
1053	}
1054	else
1055		neo_set_no_input_flow_control(ch);
1056	/*
1057	 * Adjust the RX FIFO Trigger level if baud is less than 9600.
1058	 * Not exactly elegant, but this is needed because of the Exar chip's
1059	 * delay on firing off the RX FIFO interrupt on slower baud rates.
1060	 */
1061	if (baud < 9600) {
1062		writeb(1, &ch->ch_neo_uart->rfifo);
1063		ch->ch_r_tlevel = 1;
1064	}
1065
1066	neo_assert_modem_signals(ch);
1067
1068	/* Get current status of the modem signals now */
1069	neo_parse_modem(ch, readb(&ch->ch_neo_uart->msr));
1070	return;
1071}
1072
1073/*
1074 * jsm_neo_intr()
1075 *
1076 * Neo specific interrupt handler.
1077 */
1078static irqreturn_t neo_intr(int irq, void *voidbrd)
1079{
1080	struct jsm_board *brd = voidbrd;
1081	struct jsm_channel *ch;
1082	int port = 0;
1083	int type = 0;
1084	int current_port;
1085	u32 tmp;
1086	u32 uart_poll;
1087	unsigned long lock_flags;
1088	unsigned long lock_flags2;
1089	int outofloop_count = 0;
1090
1091	/* Lock out the slow poller from running on this board. */
1092	spin_lock_irqsave(&brd->bd_intr_lock, lock_flags);
1093
1094	/*
1095	 * Read in "extended" IRQ information from the 32bit Neo register.
1096	 * Bits 0-7: What port triggered the interrupt.
1097	 * Bits 8-31: Each 3bits indicate what type of interrupt occurred.
1098	 */
1099	uart_poll = readl(brd->re_map_membase + UART_17158_POLL_ADDR_OFFSET);
1100
1101	jsm_dbg(INTR, &brd->pci_dev, "%s:%d uart_poll: %x\n",
1102		__FILE__, __LINE__, uart_poll);
1103
1104	if (!uart_poll) {
1105		jsm_dbg(INTR, &brd->pci_dev,
1106			"Kernel interrupted to me, but no pending interrupts...\n");
1107		spin_unlock_irqrestore(&brd->bd_intr_lock, lock_flags);
1108		return IRQ_NONE;
1109	}
1110
1111	/* At this point, we have at least SOMETHING to service, dig further... */
1112
1113	current_port = 0;
1114
1115	/* Loop on each port */
1116	while (((uart_poll & 0xff) != 0) && (outofloop_count < 0xff)){
1117
1118		tmp = uart_poll;
1119		outofloop_count++;
1120
1121		/* Check current port to see if it has interrupt pending */
1122		if ((tmp & jsm_offset_table[current_port]) != 0) {
1123			port = current_port;
1124			type = tmp >> (8 + (port * 3));
1125			type &= 0x7;
1126		} else {
1127			current_port++;
1128			continue;
1129		}
1130
1131		jsm_dbg(INTR, &brd->pci_dev, "%s:%d port: %x type: %x\n",
1132			__FILE__, __LINE__, port, type);
1133
1134		/* Remove this port + type from uart_poll */
1135		uart_poll &= ~(jsm_offset_table[port]);
1136
1137		if (!type) {
1138			/* If no type, just ignore it, and move onto next port */
1139			jsm_dbg(INTR, &brd->pci_dev,
1140				"Interrupt with no type! port: %d\n", port);
1141			continue;
1142		}
1143
1144		/* Switch on type of interrupt we have */
1145		switch (type) {
1146
1147		case UART_17158_RXRDY_TIMEOUT:
1148			/*
1149			 * RXRDY Time-out is cleared by reading data in the
1150			* RX FIFO until it falls below the trigger level.
1151			 */
1152
1153			/* Verify the port is in range. */
1154			if (port >= brd->nasync)
1155				continue;
1156
1157			ch = brd->channels[port];
1158			if (!ch)
1159				continue;
1160
1161			neo_copy_data_from_uart_to_queue(ch);
1162
1163			/* Call our tty layer to enforce queue flow control if needed. */
1164			spin_lock_irqsave(&ch->ch_lock, lock_flags2);
1165			jsm_check_queue_flow_control(ch);
1166			spin_unlock_irqrestore(&ch->ch_lock, lock_flags2);
1167
1168			continue;
1169
1170		case UART_17158_RX_LINE_STATUS:
1171			/*
1172			 * RXRDY and RX LINE Status (logic OR of LSR[4:1])
1173			 */
1174			neo_parse_lsr(brd, port);
1175			continue;
1176
1177		case UART_17158_TXRDY:
1178			/*
1179			 * TXRDY interrupt clears after reading ISR register for the UART channel.
1180			 */
1181
1182			/*
1183			 * Yes, this is odd...
1184			 * Why would I check EVERY possibility of type of
1185			 * interrupt, when we know its TXRDY???
1186			 * Becuz for some reason, even tho we got triggered for TXRDY,
1187			 * it seems to be occasionally wrong. Instead of TX, which
1188			 * it should be, I was getting things like RXDY too. Weird.
1189			 */
1190			neo_parse_isr(brd, port);
1191			continue;
1192
1193		case UART_17158_MSR:
1194			/*
1195			 * MSR or flow control was seen.
1196			 */
1197			neo_parse_isr(brd, port);
1198			continue;
1199
1200		default:
1201			/*
1202			 * The UART triggered us with a bogus interrupt type.
1203			 * It appears the Exar chip, when REALLY bogged down, will throw
1204			 * these once and awhile.
1205			 * Its harmless, just ignore it and move on.
1206			 */
1207			jsm_dbg(INTR, &brd->pci_dev,
1208				"%s:%d Unknown Interrupt type: %x\n",
1209				__FILE__, __LINE__, type);
1210			continue;
1211		}
1212	}
1213
1214	spin_unlock_irqrestore(&brd->bd_intr_lock, lock_flags);
1215
1216	jsm_dbg(INTR, &brd->pci_dev, "finish\n");
1217	return IRQ_HANDLED;
1218}
1219
1220/*
1221 * Neo specific way of turning off the receiver.
1222 * Used as a way to enforce queue flow control when in
1223 * hardware flow control mode.
1224 */
1225static void neo_disable_receiver(struct jsm_channel *ch)
1226{
1227	u8 tmp = readb(&ch->ch_neo_uart->ier);
1228	tmp &= ~(UART_IER_RDI);
1229	writeb(tmp, &ch->ch_neo_uart->ier);
1230
1231	/* flush write operation */
1232	neo_pci_posting_flush(ch->ch_bd);
1233}
1234
1235
1236/*
1237 * Neo specific way of turning on the receiver.
1238 * Used as a way to un-enforce queue flow control when in
1239 * hardware flow control mode.
1240 */
1241static void neo_enable_receiver(struct jsm_channel *ch)
1242{
1243	u8 tmp = readb(&ch->ch_neo_uart->ier);
1244	tmp |= (UART_IER_RDI);
1245	writeb(tmp, &ch->ch_neo_uart->ier);
1246
1247	/* flush write operation */
1248	neo_pci_posting_flush(ch->ch_bd);
1249}
1250
1251static void neo_send_start_character(struct jsm_channel *ch)
1252{
1253	if (!ch)
1254		return;
1255
1256	if (ch->ch_startc != __DISABLED_CHAR) {
1257		ch->ch_xon_sends++;
1258		writeb(ch->ch_startc, &ch->ch_neo_uart->txrx);
1259
1260		/* flush write operation */
1261		neo_pci_posting_flush(ch->ch_bd);
1262	}
1263}
1264
1265static void neo_send_stop_character(struct jsm_channel *ch)
1266{
1267	if (!ch)
1268		return;
1269
1270	if (ch->ch_stopc != __DISABLED_CHAR) {
1271		ch->ch_xoff_sends++;
1272		writeb(ch->ch_stopc, &ch->ch_neo_uart->txrx);
1273
1274		/* flush write operation */
1275		neo_pci_posting_flush(ch->ch_bd);
1276	}
1277}
1278
1279/*
1280 * neo_uart_init
1281 */
1282static void neo_uart_init(struct jsm_channel *ch)
1283{
1284	writeb(0, &ch->ch_neo_uart->ier);
1285	writeb(0, &ch->ch_neo_uart->efr);
1286	writeb(UART_EFR_ECB, &ch->ch_neo_uart->efr);
1287
1288	/* Clear out UART and FIFO */
1289	readb(&ch->ch_neo_uart->txrx);
1290	writeb((UART_FCR_ENABLE_FIFO|UART_FCR_CLEAR_RCVR|UART_FCR_CLEAR_XMIT), &ch->ch_neo_uart->isr_fcr);
1291	readb(&ch->ch_neo_uart->lsr);
1292	readb(&ch->ch_neo_uart->msr);
1293
1294	ch->ch_flags |= CH_FIFO_ENABLED;
1295
1296	/* Assert any signals we want up */
1297	writeb(ch->ch_mostat, &ch->ch_neo_uart->mcr);
1298}
1299
1300/*
1301 * Make the UART completely turn off.
1302 */
1303static void neo_uart_off(struct jsm_channel *ch)
1304{
1305	/* Turn off UART enhanced bits */
1306	writeb(0, &ch->ch_neo_uart->efr);
1307
1308	/* Stop all interrupts from occurring. */
1309	writeb(0, &ch->ch_neo_uart->ier);
1310}
1311
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1312/* Channel lock MUST be held by the calling function! */
1313static void neo_send_break(struct jsm_channel *ch)
1314{
1315	/*
1316	 * Set the time we should stop sending the break.
1317	 * If we are already sending a break, toss away the existing
1318	 * time to stop, and use this new value instead.
1319	 */
1320
1321	/* Tell the UART to start sending the break */
1322	if (!(ch->ch_flags & CH_BREAK_SENDING)) {
1323		u8 temp = readb(&ch->ch_neo_uart->lcr);
1324		writeb((temp | UART_LCR_SBC), &ch->ch_neo_uart->lcr);
1325		ch->ch_flags |= (CH_BREAK_SENDING);
1326
1327		/* flush write operation */
1328		neo_pci_posting_flush(ch->ch_bd);
1329	}
1330}
1331
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1332struct board_ops jsm_neo_ops = {
1333	.intr				= neo_intr,
1334	.uart_init			= neo_uart_init,
1335	.uart_off			= neo_uart_off,
1336	.param				= neo_param,
1337	.assert_modem_signals		= neo_assert_modem_signals,
1338	.flush_uart_write		= neo_flush_uart_write,
1339	.flush_uart_read		= neo_flush_uart_read,
1340	.disable_receiver		= neo_disable_receiver,
1341	.enable_receiver		= neo_enable_receiver,
1342	.send_break			= neo_send_break,
1343	.clear_break			= neo_clear_break,
1344	.send_start_character		= neo_send_start_character,
1345	.send_stop_character		= neo_send_stop_character,
1346	.copy_data_from_queue_to_uart	= neo_copy_data_from_queue_to_uart,
 
 
1347};
v4.10.11
 
   1/************************************************************************
   2 * Copyright 2003 Digi International (www.digi.com)
   3 *
   4 * Copyright (C) 2004 IBM Corporation. All rights reserved.
   5 *
   6 * This program is free software; you can redistribute it and/or modify
   7 * it under the terms of the GNU General Public License as published by
   8 * the Free Software Foundation; either version 2, or (at your option)
   9 * any later version.
  10 *
  11 * This program is distributed in the hope that it will be useful,
  12 * but WITHOUT ANY WARRANTY, EXPRESS OR IMPLIED; without even the
  13 * implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
  14 * PURPOSE.  See the GNU General Public License for more details.
  15 *
  16 * Contact Information:
  17 * Scott H Kilau <Scott_Kilau@digi.com>
  18 * Wendy Xiong   <wendyx@us.ibm.com>
  19 *
  20 ***********************************************************************/
  21#include <linux/delay.h>	/* For udelay */
  22#include <linux/serial_reg.h>	/* For the various UART offsets */
  23#include <linux/tty.h>
  24#include <linux/pci.h>
  25#include <asm/io.h>
  26
  27#include "jsm.h"		/* Driver main header file */
  28
  29static u32 jsm_offset_table[8] = { 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80 };
  30
  31/*
  32 * This function allows calls to ensure that all outstanding
  33 * PCI writes have been completed, by doing a PCI read against
  34 * a non-destructive, read-only location on the Neo card.
  35 *
  36 * In this case, we are reading the DVID (Read-only Device Identification)
  37 * value of the Neo card.
  38 */
  39static inline void neo_pci_posting_flush(struct jsm_board *bd)
  40{
  41      readb(bd->re_map_membase + 0x8D);
  42}
  43
  44static void neo_set_cts_flow_control(struct jsm_channel *ch)
  45{
  46	u8 ier, efr;
  47	ier = readb(&ch->ch_neo_uart->ier);
  48	efr = readb(&ch->ch_neo_uart->efr);
  49
  50	jsm_dbg(PARAM, &ch->ch_bd->pci_dev, "Setting CTSFLOW\n");
  51
  52	/* Turn on auto CTS flow control */
  53	ier |= (UART_17158_IER_CTSDSR);
  54	efr |= (UART_17158_EFR_ECB | UART_17158_EFR_CTSDSR);
  55
  56	/* Turn off auto Xon flow control */
  57	efr &= ~(UART_17158_EFR_IXON);
  58
  59	/* Why? Becuz Exar's spec says we have to zero it out before setting it */
  60	writeb(0, &ch->ch_neo_uart->efr);
  61
  62	/* Turn on UART enhanced bits */
  63	writeb(efr, &ch->ch_neo_uart->efr);
  64
  65	/* Turn on table D, with 8 char hi/low watermarks */
  66	writeb((UART_17158_FCTR_TRGD | UART_17158_FCTR_RTS_4DELAY), &ch->ch_neo_uart->fctr);
  67
  68	/* Feed the UART our trigger levels */
  69	writeb(8, &ch->ch_neo_uart->tfifo);
  70	ch->ch_t_tlevel = 8;
  71
  72	writeb(ier, &ch->ch_neo_uart->ier);
  73}
  74
  75static void neo_set_rts_flow_control(struct jsm_channel *ch)
  76{
  77	u8 ier, efr;
  78	ier = readb(&ch->ch_neo_uart->ier);
  79	efr = readb(&ch->ch_neo_uart->efr);
  80
  81	jsm_dbg(PARAM, &ch->ch_bd->pci_dev, "Setting RTSFLOW\n");
  82
  83	/* Turn on auto RTS flow control */
  84	ier |= (UART_17158_IER_RTSDTR);
  85	efr |= (UART_17158_EFR_ECB | UART_17158_EFR_RTSDTR);
  86
  87	/* Turn off auto Xoff flow control */
  88	ier &= ~(UART_17158_IER_XOFF);
  89	efr &= ~(UART_17158_EFR_IXOFF);
  90
  91	/* Why? Becuz Exar's spec says we have to zero it out before setting it */
  92	writeb(0, &ch->ch_neo_uart->efr);
  93
  94	/* Turn on UART enhanced bits */
  95	writeb(efr, &ch->ch_neo_uart->efr);
  96
  97	writeb((UART_17158_FCTR_TRGD | UART_17158_FCTR_RTS_4DELAY), &ch->ch_neo_uart->fctr);
  98	ch->ch_r_watermark = 4;
  99
 100	writeb(56, &ch->ch_neo_uart->rfifo);
 101	ch->ch_r_tlevel = 56;
 102
 103	writeb(ier, &ch->ch_neo_uart->ier);
 104
 105	/*
 106	 * From the Neo UART spec sheet:
 107	 * The auto RTS/DTR function must be started by asserting
 108	 * RTS/DTR# output pin (MCR bit-0 or 1 to logic 1 after
 109	 * it is enabled.
 110	 */
 111	ch->ch_mostat |= (UART_MCR_RTS);
 112}
 113
 114
 115static void neo_set_ixon_flow_control(struct jsm_channel *ch)
 116{
 117	u8 ier, efr;
 118	ier = readb(&ch->ch_neo_uart->ier);
 119	efr = readb(&ch->ch_neo_uart->efr);
 120
 121	jsm_dbg(PARAM, &ch->ch_bd->pci_dev, "Setting IXON FLOW\n");
 122
 123	/* Turn off auto CTS flow control */
 124	ier &= ~(UART_17158_IER_CTSDSR);
 125	efr &= ~(UART_17158_EFR_CTSDSR);
 126
 127	/* Turn on auto Xon flow control */
 128	efr |= (UART_17158_EFR_ECB | UART_17158_EFR_IXON);
 129
 130	/* Why? Becuz Exar's spec says we have to zero it out before setting it */
 131	writeb(0, &ch->ch_neo_uart->efr);
 132
 133	/* Turn on UART enhanced bits */
 134	writeb(efr, &ch->ch_neo_uart->efr);
 135
 136	writeb((UART_17158_FCTR_TRGD | UART_17158_FCTR_RTS_8DELAY), &ch->ch_neo_uart->fctr);
 137	ch->ch_r_watermark = 4;
 138
 139	writeb(32, &ch->ch_neo_uart->rfifo);
 140	ch->ch_r_tlevel = 32;
 141
 142	/* Tell UART what start/stop chars it should be looking for */
 143	writeb(ch->ch_startc, &ch->ch_neo_uart->xonchar1);
 144	writeb(0, &ch->ch_neo_uart->xonchar2);
 145
 146	writeb(ch->ch_stopc, &ch->ch_neo_uart->xoffchar1);
 147	writeb(0, &ch->ch_neo_uart->xoffchar2);
 148
 149	writeb(ier, &ch->ch_neo_uart->ier);
 150}
 151
 152static void neo_set_ixoff_flow_control(struct jsm_channel *ch)
 153{
 154	u8 ier, efr;
 155	ier = readb(&ch->ch_neo_uart->ier);
 156	efr = readb(&ch->ch_neo_uart->efr);
 157
 158	jsm_dbg(PARAM, &ch->ch_bd->pci_dev, "Setting IXOFF FLOW\n");
 159
 160	/* Turn off auto RTS flow control */
 161	ier &= ~(UART_17158_IER_RTSDTR);
 162	efr &= ~(UART_17158_EFR_RTSDTR);
 163
 164	/* Turn on auto Xoff flow control */
 165	ier |= (UART_17158_IER_XOFF);
 166	efr |= (UART_17158_EFR_ECB | UART_17158_EFR_IXOFF);
 167
 168	/* Why? Becuz Exar's spec says we have to zero it out before setting it */
 169	writeb(0, &ch->ch_neo_uart->efr);
 170
 171	/* Turn on UART enhanced bits */
 172	writeb(efr, &ch->ch_neo_uart->efr);
 173
 174	/* Turn on table D, with 8 char hi/low watermarks */
 175	writeb((UART_17158_FCTR_TRGD | UART_17158_FCTR_RTS_8DELAY), &ch->ch_neo_uart->fctr);
 176
 177	writeb(8, &ch->ch_neo_uart->tfifo);
 178	ch->ch_t_tlevel = 8;
 179
 180	/* Tell UART what start/stop chars it should be looking for */
 181	writeb(ch->ch_startc, &ch->ch_neo_uart->xonchar1);
 182	writeb(0, &ch->ch_neo_uart->xonchar2);
 183
 184	writeb(ch->ch_stopc, &ch->ch_neo_uart->xoffchar1);
 185	writeb(0, &ch->ch_neo_uart->xoffchar2);
 186
 187	writeb(ier, &ch->ch_neo_uart->ier);
 188}
 189
 190static void neo_set_no_input_flow_control(struct jsm_channel *ch)
 191{
 192	u8 ier, efr;
 193	ier = readb(&ch->ch_neo_uart->ier);
 194	efr = readb(&ch->ch_neo_uart->efr);
 195
 196	jsm_dbg(PARAM, &ch->ch_bd->pci_dev, "Unsetting Input FLOW\n");
 197
 198	/* Turn off auto RTS flow control */
 199	ier &= ~(UART_17158_IER_RTSDTR);
 200	efr &= ~(UART_17158_EFR_RTSDTR);
 201
 202	/* Turn off auto Xoff flow control */
 203	ier &= ~(UART_17158_IER_XOFF);
 204	if (ch->ch_c_iflag & IXON)
 205		efr &= ~(UART_17158_EFR_IXOFF);
 206	else
 207		efr &= ~(UART_17158_EFR_ECB | UART_17158_EFR_IXOFF);
 208
 209	/* Why? Becuz Exar's spec says we have to zero it out before setting it */
 210	writeb(0, &ch->ch_neo_uart->efr);
 211
 212	/* Turn on UART enhanced bits */
 213	writeb(efr, &ch->ch_neo_uart->efr);
 214
 215	/* Turn on table D, with 8 char hi/low watermarks */
 216	writeb((UART_17158_FCTR_TRGD | UART_17158_FCTR_RTS_8DELAY), &ch->ch_neo_uart->fctr);
 217
 218	ch->ch_r_watermark = 0;
 219
 220	writeb(16, &ch->ch_neo_uart->tfifo);
 221	ch->ch_t_tlevel = 16;
 222
 223	writeb(16, &ch->ch_neo_uart->rfifo);
 224	ch->ch_r_tlevel = 16;
 225
 226	writeb(ier, &ch->ch_neo_uart->ier);
 227}
 228
 229static void neo_set_no_output_flow_control(struct jsm_channel *ch)
 230{
 231	u8 ier, efr;
 232	ier = readb(&ch->ch_neo_uart->ier);
 233	efr = readb(&ch->ch_neo_uart->efr);
 234
 235	jsm_dbg(PARAM, &ch->ch_bd->pci_dev, "Unsetting Output FLOW\n");
 236
 237	/* Turn off auto CTS flow control */
 238	ier &= ~(UART_17158_IER_CTSDSR);
 239	efr &= ~(UART_17158_EFR_CTSDSR);
 240
 241	/* Turn off auto Xon flow control */
 242	if (ch->ch_c_iflag & IXOFF)
 243		efr &= ~(UART_17158_EFR_IXON);
 244	else
 245		efr &= ~(UART_17158_EFR_ECB | UART_17158_EFR_IXON);
 246
 247	/* Why? Becuz Exar's spec says we have to zero it out before setting it */
 248	writeb(0, &ch->ch_neo_uart->efr);
 249
 250	/* Turn on UART enhanced bits */
 251	writeb(efr, &ch->ch_neo_uart->efr);
 252
 253	/* Turn on table D, with 8 char hi/low watermarks */
 254	writeb((UART_17158_FCTR_TRGD | UART_17158_FCTR_RTS_8DELAY), &ch->ch_neo_uart->fctr);
 255
 256	ch->ch_r_watermark = 0;
 257
 258	writeb(16, &ch->ch_neo_uart->tfifo);
 259	ch->ch_t_tlevel = 16;
 260
 261	writeb(16, &ch->ch_neo_uart->rfifo);
 262	ch->ch_r_tlevel = 16;
 263
 264	writeb(ier, &ch->ch_neo_uart->ier);
 265}
 266
 267static inline void neo_set_new_start_stop_chars(struct jsm_channel *ch)
 268{
 269
 270	/* if hardware flow control is set, then skip this whole thing */
 271	if (ch->ch_c_cflag & CRTSCTS)
 272		return;
 273
 274	jsm_dbg(PARAM, &ch->ch_bd->pci_dev, "start\n");
 275
 276	/* Tell UART what start/stop chars it should be looking for */
 277	writeb(ch->ch_startc, &ch->ch_neo_uart->xonchar1);
 278	writeb(0, &ch->ch_neo_uart->xonchar2);
 279
 280	writeb(ch->ch_stopc, &ch->ch_neo_uart->xoffchar1);
 281	writeb(0, &ch->ch_neo_uart->xoffchar2);
 282}
 283
 284static void neo_copy_data_from_uart_to_queue(struct jsm_channel *ch)
 285{
 286	int qleft = 0;
 287	u8 linestatus = 0;
 288	u8 error_mask = 0;
 289	int n = 0;
 290	int total = 0;
 291	u16 head;
 292	u16 tail;
 293
 294	if (!ch)
 295		return;
 296
 297	/* cache head and tail of queue */
 298	head = ch->ch_r_head & RQUEUEMASK;
 299	tail = ch->ch_r_tail & RQUEUEMASK;
 300
 301	/* Get our cached LSR */
 302	linestatus = ch->ch_cached_lsr;
 303	ch->ch_cached_lsr = 0;
 304
 305	/* Store how much space we have left in the queue */
 306	if ((qleft = tail - head - 1) < 0)
 
 307		qleft += RQUEUEMASK + 1;
 308
 309	/*
 310	 * If the UART is not in FIFO mode, force the FIFO copy to
 311	 * NOT be run, by setting total to 0.
 312	 *
 313	 * On the other hand, if the UART IS in FIFO mode, then ask
 314	 * the UART to give us an approximation of data it has RX'ed.
 315	 */
 316	if (!(ch->ch_flags & CH_FIFO_ENABLED))
 317		total = 0;
 318	else {
 319		total = readb(&ch->ch_neo_uart->rfifo);
 320
 321		/*
 322		 * EXAR chip bug - RX FIFO COUNT - Fudge factor.
 323		 *
 324		 * This resolves a problem/bug with the Exar chip that sometimes
 325		 * returns a bogus value in the rfifo register.
 326		 * The count can be any where from 0-3 bytes "off".
 327		 * Bizarre, but true.
 328		 */
 329		total -= 3;
 330	}
 331
 332	/*
 333	 * Finally, bound the copy to make sure we don't overflow
 334	 * our own queue...
 335	 * The byte by byte copy loop below this loop this will
 336	 * deal with the queue overflow possibility.
 337	 */
 338	total = min(total, qleft);
 339
 340	while (total > 0) {
 341		/*
 342		 * Grab the linestatus register, we need to check
 343		 * to see if there are any errors in the FIFO.
 344		 */
 345		linestatus = readb(&ch->ch_neo_uart->lsr);
 346
 347		/*
 348		 * Break out if there is a FIFO error somewhere.
 349		 * This will allow us to go byte by byte down below,
 350		 * finding the exact location of the error.
 351		 */
 352		if (linestatus & UART_17158_RX_FIFO_DATA_ERROR)
 353			break;
 354
 355		/* Make sure we don't go over the end of our queue */
 356		n = min(((u32) total), (RQUEUESIZE - (u32) head));
 357
 358		/*
 359		 * Cut down n even further if needed, this is to fix
 360		 * a problem with memcpy_fromio() with the Neo on the
 361		 * IBM pSeries platform.
 362		 * 15 bytes max appears to be the magic number.
 363		 */
 364		n = min((u32) n, (u32) 12);
 365
 366		/*
 367		 * Since we are grabbing the linestatus register, which
 368		 * will reset some bits after our read, we need to ensure
 369		 * we don't miss our TX FIFO emptys.
 370		 */
 371		if (linestatus & (UART_LSR_THRE | UART_17158_TX_AND_FIFO_CLR))
 372			ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
 373
 374		linestatus = 0;
 375
 376		/* Copy data from uart to the queue */
 377		memcpy_fromio(ch->ch_rqueue + head, &ch->ch_neo_uart->txrxburst, n);
 378		/*
 379		 * Since RX_FIFO_DATA_ERROR was 0, we are guaranteed
 380		 * that all the data currently in the FIFO is free of
 381		 * breaks and parity/frame/orun errors.
 382		 */
 383		memset(ch->ch_equeue + head, 0, n);
 384
 385		/* Add to and flip head if needed */
 386		head = (head + n) & RQUEUEMASK;
 387		total -= n;
 388		qleft -= n;
 389		ch->ch_rxcount += n;
 390	}
 391
 392	/*
 393	 * Create a mask to determine whether we should
 394	 * insert the character (if any) into our queue.
 395	 */
 396	if (ch->ch_c_iflag & IGNBRK)
 397		error_mask |= UART_LSR_BI;
 398
 399	/*
 400	 * Now cleanup any leftover bytes still in the UART.
 401	 * Also deal with any possible queue overflow here as well.
 402	 */
 403	while (1) {
 404
 405		/*
 406		 * Its possible we have a linestatus from the loop above
 407		 * this, so we "OR" on any extra bits.
 408		 */
 409		linestatus |= readb(&ch->ch_neo_uart->lsr);
 410
 411		/*
 412		 * If the chip tells us there is no more data pending to
 413		 * be read, we can then leave.
 414		 * But before we do, cache the linestatus, just in case.
 415		 */
 416		if (!(linestatus & UART_LSR_DR)) {
 417			ch->ch_cached_lsr = linestatus;
 418			break;
 419		}
 420
 421		/* No need to store this bit */
 422		linestatus &= ~UART_LSR_DR;
 423
 424		/*
 425		 * Since we are grabbing the linestatus register, which
 426		 * will reset some bits after our read, we need to ensure
 427		 * we don't miss our TX FIFO emptys.
 428		 */
 429		if (linestatus & (UART_LSR_THRE | UART_17158_TX_AND_FIFO_CLR)) {
 430			linestatus &= ~(UART_LSR_THRE | UART_17158_TX_AND_FIFO_CLR);
 431			ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
 432		}
 433
 434		/*
 435		 * Discard character if we are ignoring the error mask.
 436		 */
 437		if (linestatus & error_mask) {
 438			u8 discard;
 439			linestatus = 0;
 440			memcpy_fromio(&discard, &ch->ch_neo_uart->txrxburst, 1);
 441			continue;
 442		}
 443
 444		/*
 445		 * If our queue is full, we have no choice but to drop some data.
 446		 * The assumption is that HWFLOW or SWFLOW should have stopped
 447		 * things way way before we got to this point.
 448		 *
 449		 * I decided that I wanted to ditch the oldest data first,
 450		 * I hope thats okay with everyone? Yes? Good.
 451		 */
 452		while (qleft < 1) {
 453			jsm_dbg(READ, &ch->ch_bd->pci_dev,
 454				"Queue full, dropping DATA:%x LSR:%x\n",
 455				ch->ch_rqueue[tail], ch->ch_equeue[tail]);
 456
 457			ch->ch_r_tail = tail = (tail + 1) & RQUEUEMASK;
 458			ch->ch_err_overrun++;
 459			qleft++;
 460		}
 461
 462		memcpy_fromio(ch->ch_rqueue + head, &ch->ch_neo_uart->txrxburst, 1);
 463		ch->ch_equeue[head] = (u8) linestatus;
 464
 465		jsm_dbg(READ, &ch->ch_bd->pci_dev, "DATA/LSR pair: %x %x\n",
 466			ch->ch_rqueue[head], ch->ch_equeue[head]);
 467
 468		/* Ditch any remaining linestatus value. */
 469		linestatus = 0;
 470
 471		/* Add to and flip head if needed */
 472		head = (head + 1) & RQUEUEMASK;
 473
 474		qleft--;
 475		ch->ch_rxcount++;
 476	}
 477
 478	/*
 479	 * Write new final heads to channel structure.
 480	 */
 481	ch->ch_r_head = head & RQUEUEMASK;
 482	ch->ch_e_head = head & EQUEUEMASK;
 483	jsm_input(ch);
 484}
 485
 486static void neo_copy_data_from_queue_to_uart(struct jsm_channel *ch)
 487{
 488	u16 head;
 489	u16 tail;
 490	int n;
 491	int s;
 492	int qlen;
 493	u32 len_written = 0;
 494	struct circ_buf *circ;
 495
 496	if (!ch)
 497		return;
 498
 499	circ = &ch->uart_port.state->xmit;
 500
 501	/* No data to write to the UART */
 502	if (uart_circ_empty(circ))
 503		return;
 504
 505	/* If port is "stopped", don't send any data to the UART */
 506	if ((ch->ch_flags & CH_STOP) || (ch->ch_flags & CH_BREAK_SENDING))
 507		return;
 508	/*
 509	 * If FIFOs are disabled. Send data directly to txrx register
 510	 */
 511	if (!(ch->ch_flags & CH_FIFO_ENABLED)) {
 512		u8 lsrbits = readb(&ch->ch_neo_uart->lsr);
 513
 514		ch->ch_cached_lsr |= lsrbits;
 515		if (ch->ch_cached_lsr & UART_LSR_THRE) {
 516			ch->ch_cached_lsr &= ~(UART_LSR_THRE);
 517
 518			writeb(circ->buf[circ->tail], &ch->ch_neo_uart->txrx);
 519			jsm_dbg(WRITE, &ch->ch_bd->pci_dev,
 520				"Tx data: %x\n", circ->buf[circ->tail]);
 521			circ->tail = (circ->tail + 1) & (UART_XMIT_SIZE - 1);
 522			ch->ch_txcount++;
 523		}
 524		return;
 525	}
 526
 527	/*
 528	 * We have to do it this way, because of the EXAR TXFIFO count bug.
 529	 */
 530	if (!(ch->ch_flags & (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM)))
 531		return;
 532
 533	n = UART_17158_TX_FIFOSIZE - ch->ch_t_tlevel;
 534
 535	/* cache head and tail of queue */
 536	head = circ->head & (UART_XMIT_SIZE - 1);
 537	tail = circ->tail & (UART_XMIT_SIZE - 1);
 538	qlen = uart_circ_chars_pending(circ);
 539
 540	/* Find minimum of the FIFO space, versus queue length */
 541	n = min(n, qlen);
 542
 543	while (n > 0) {
 544
 545		s = ((head >= tail) ? head : UART_XMIT_SIZE) - tail;
 546		s = min(s, n);
 547
 548		if (s <= 0)
 549			break;
 550
 551		memcpy_toio(&ch->ch_neo_uart->txrxburst, circ->buf + tail, s);
 552		/* Add and flip queue if needed */
 553		tail = (tail + s) & (UART_XMIT_SIZE - 1);
 554		n -= s;
 555		ch->ch_txcount += s;
 556		len_written += s;
 557	}
 558
 559	/* Update the final tail */
 560	circ->tail = tail & (UART_XMIT_SIZE - 1);
 561
 562	if (len_written >= ch->ch_t_tlevel)
 563		ch->ch_flags &= ~(CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
 564
 565	if (uart_circ_empty(circ))
 566		uart_write_wakeup(&ch->uart_port);
 567}
 568
 569static void neo_parse_modem(struct jsm_channel *ch, u8 signals)
 570{
 571	u8 msignals = signals;
 572
 573	jsm_dbg(MSIGS, &ch->ch_bd->pci_dev,
 574		"neo_parse_modem: port: %d msignals: %x\n",
 575		ch->ch_portnum, msignals);
 576
 577	/* Scrub off lower bits. They signify delta's, which I don't care about */
 578	/* Keep DDCD and DDSR though */
 579	msignals &= 0xf8;
 580
 581	if (msignals & UART_MSR_DDCD)
 582		uart_handle_dcd_change(&ch->uart_port, msignals & UART_MSR_DCD);
 583	if (msignals & UART_MSR_DDSR)
 584		uart_handle_cts_change(&ch->uart_port, msignals & UART_MSR_CTS);
 585	if (msignals & UART_MSR_DCD)
 586		ch->ch_mistat |= UART_MSR_DCD;
 587	else
 588		ch->ch_mistat &= ~UART_MSR_DCD;
 589
 590	if (msignals & UART_MSR_DSR)
 591		ch->ch_mistat |= UART_MSR_DSR;
 592	else
 593		ch->ch_mistat &= ~UART_MSR_DSR;
 594
 595	if (msignals & UART_MSR_RI)
 596		ch->ch_mistat |= UART_MSR_RI;
 597	else
 598		ch->ch_mistat &= ~UART_MSR_RI;
 599
 600	if (msignals & UART_MSR_CTS)
 601		ch->ch_mistat |= UART_MSR_CTS;
 602	else
 603		ch->ch_mistat &= ~UART_MSR_CTS;
 604
 605	jsm_dbg(MSIGS, &ch->ch_bd->pci_dev,
 606		"Port: %d DTR: %d RTS: %d CTS: %d DSR: %d " "RI: %d CD: %d\n",
 607		ch->ch_portnum,
 608		!!((ch->ch_mistat | ch->ch_mostat) & UART_MCR_DTR),
 609		!!((ch->ch_mistat | ch->ch_mostat) & UART_MCR_RTS),
 610		!!((ch->ch_mistat | ch->ch_mostat) & UART_MSR_CTS),
 611		!!((ch->ch_mistat | ch->ch_mostat) & UART_MSR_DSR),
 612		!!((ch->ch_mistat | ch->ch_mostat) & UART_MSR_RI),
 613		!!((ch->ch_mistat | ch->ch_mostat) & UART_MSR_DCD));
 614}
 615
 616/* Make the UART raise any of the output signals we want up */
 617static void neo_assert_modem_signals(struct jsm_channel *ch)
 618{
 619	if (!ch)
 620		return;
 621
 622	writeb(ch->ch_mostat, &ch->ch_neo_uart->mcr);
 623
 624	/* flush write operation */
 625	neo_pci_posting_flush(ch->ch_bd);
 626}
 627
 628/*
 629 * Flush the WRITE FIFO on the Neo.
 630 *
 631 * NOTE: Channel lock MUST be held before calling this function!
 632 */
 633static void neo_flush_uart_write(struct jsm_channel *ch)
 634{
 635	u8 tmp = 0;
 636	int i = 0;
 637
 638	if (!ch)
 639		return;
 640
 641	writeb((UART_FCR_ENABLE_FIFO | UART_FCR_CLEAR_XMIT), &ch->ch_neo_uart->isr_fcr);
 642
 643	for (i = 0; i < 10; i++) {
 644
 645		/* Check to see if the UART feels it completely flushed the FIFO. */
 646		tmp = readb(&ch->ch_neo_uart->isr_fcr);
 647		if (tmp & UART_FCR_CLEAR_XMIT) {
 648			jsm_dbg(IOCTL, &ch->ch_bd->pci_dev,
 649				"Still flushing TX UART... i: %d\n", i);
 650			udelay(10);
 651		}
 652		else
 653			break;
 654	}
 655
 656	ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
 657}
 658
 659
 660/*
 661 * Flush the READ FIFO on the Neo.
 662 *
 663 * NOTE: Channel lock MUST be held before calling this function!
 664 */
 665static void neo_flush_uart_read(struct jsm_channel *ch)
 666{
 667	u8 tmp = 0;
 668	int i = 0;
 669
 670	if (!ch)
 671		return;
 672
 673	writeb((UART_FCR_ENABLE_FIFO | UART_FCR_CLEAR_RCVR), &ch->ch_neo_uart->isr_fcr);
 674
 675	for (i = 0; i < 10; i++) {
 676
 677		/* Check to see if the UART feels it completely flushed the FIFO. */
 678		tmp = readb(&ch->ch_neo_uart->isr_fcr);
 679		if (tmp & 2) {
 680			jsm_dbg(IOCTL, &ch->ch_bd->pci_dev,
 681				"Still flushing RX UART... i: %d\n", i);
 682			udelay(10);
 683		}
 684		else
 685			break;
 686	}
 687}
 688
 689/*
 690 * No locks are assumed to be held when calling this function.
 691 */
 692static void neo_clear_break(struct jsm_channel *ch)
 693{
 694	unsigned long lock_flags;
 695
 696	spin_lock_irqsave(&ch->ch_lock, lock_flags);
 697
 698	/* Turn break off, and unset some variables */
 699	if (ch->ch_flags & CH_BREAK_SENDING) {
 700		u8 temp = readb(&ch->ch_neo_uart->lcr);
 701		writeb((temp & ~UART_LCR_SBC), &ch->ch_neo_uart->lcr);
 702
 703		ch->ch_flags &= ~(CH_BREAK_SENDING);
 704		jsm_dbg(IOCTL, &ch->ch_bd->pci_dev,
 705			"clear break Finishing UART_LCR_SBC! finished: %lx\n",
 706			jiffies);
 707
 708		/* flush write operation */
 709		neo_pci_posting_flush(ch->ch_bd);
 710	}
 711	spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
 712}
 713
 714/*
 715 * Parse the ISR register.
 716 */
 717static void neo_parse_isr(struct jsm_board *brd, u32 port)
 718{
 719	struct jsm_channel *ch;
 720	u8 isr;
 721	u8 cause;
 722	unsigned long lock_flags;
 723
 724	if (!brd)
 725		return;
 726
 727	if (port >= brd->maxports)
 728		return;
 729
 730	ch = brd->channels[port];
 731	if (!ch)
 732		return;
 733
 734	/* Here we try to figure out what caused the interrupt to happen */
 735	while (1) {
 736
 737		isr = readb(&ch->ch_neo_uart->isr_fcr);
 738
 739		/* Bail if no pending interrupt */
 740		if (isr & UART_IIR_NO_INT)
 741			break;
 742
 743		/*
 744		 * Yank off the upper 2 bits, which just show that the FIFO's are enabled.
 745		 */
 746		isr &= ~(UART_17158_IIR_FIFO_ENABLED);
 747
 748		jsm_dbg(INTR, &ch->ch_bd->pci_dev, "%s:%d isr: %x\n",
 749			__FILE__, __LINE__, isr);
 750
 751		if (isr & (UART_17158_IIR_RDI_TIMEOUT | UART_IIR_RDI)) {
 752			/* Read data from uart -> queue */
 753			neo_copy_data_from_uart_to_queue(ch);
 754
 755			/* Call our tty layer to enforce queue flow control if needed. */
 756			spin_lock_irqsave(&ch->ch_lock, lock_flags);
 757			jsm_check_queue_flow_control(ch);
 758			spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
 759		}
 760
 761		if (isr & UART_IIR_THRI) {
 762			/* Transfer data (if any) from Write Queue -> UART. */
 763			spin_lock_irqsave(&ch->ch_lock, lock_flags);
 764			ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
 765			spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
 766			neo_copy_data_from_queue_to_uart(ch);
 767		}
 768
 769		if (isr & UART_17158_IIR_XONXOFF) {
 770			cause = readb(&ch->ch_neo_uart->xoffchar1);
 771
 772			jsm_dbg(INTR, &ch->ch_bd->pci_dev,
 773				"Port %d. Got ISR_XONXOFF: cause:%x\n",
 774				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_dbg(INTR, &ch->ch_bd->pci_dev,
 788					"Port %d. XON detected in incoming data\n",
 789					port);
 790			}
 791			else if (cause == UART_17158_XOFF_DETECT) {
 792				if (!(brd->channels[port]->ch_flags & CH_STOP)) {
 793					ch->ch_flags |= CH_STOP;
 794					jsm_dbg(INTR, &ch->ch_bd->pci_dev,
 795						"Setting CH_STOP\n");
 796				}
 797				jsm_dbg(INTR, &ch->ch_bd->pci_dev,
 798					"Port: %d. XOFF detected in incoming data\n",
 799					port);
 800			}
 801			spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
 802		}
 803
 804		if (isr & UART_17158_IIR_HWFLOW_STATE_CHANGE) {
 805			/*
 806			 * If we get here, this means the hardware is doing auto flow control.
 807			 * Check to see whether RTS/DTR or CTS/DSR caused this interrupt.
 808			 */
 809			cause = readb(&ch->ch_neo_uart->mcr);
 810
 811			/* Which pin is doing auto flow? RTS or DTR? */
 812			spin_lock_irqsave(&ch->ch_lock, lock_flags);
 813			if ((cause & 0x4) == 0) {
 814				if (cause & UART_MCR_RTS)
 815					ch->ch_mostat |= UART_MCR_RTS;
 816				else
 817					ch->ch_mostat &= ~(UART_MCR_RTS);
 818			} else {
 819				if (cause & UART_MCR_DTR)
 820					ch->ch_mostat |= UART_MCR_DTR;
 821				else
 822					ch->ch_mostat &= ~(UART_MCR_DTR);
 823			}
 824			spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
 825		}
 826
 827		/* Parse any modem signal changes */
 828		jsm_dbg(INTR, &ch->ch_bd->pci_dev,
 829			"MOD_STAT: sending to parse_modem_sigs\n");
 
 830		neo_parse_modem(ch, readb(&ch->ch_neo_uart->msr));
 
 831	}
 832}
 833
 834static inline void neo_parse_lsr(struct jsm_board *brd, u32 port)
 835{
 836	struct jsm_channel *ch;
 837	int linestatus;
 838	unsigned long lock_flags;
 839
 840	if (!brd)
 841		return;
 842
 843	if (port >= brd->maxports)
 844		return;
 845
 846	ch = brd->channels[port];
 847	if (!ch)
 848		return;
 849
 850	linestatus = readb(&ch->ch_neo_uart->lsr);
 851
 852	jsm_dbg(INTR, &ch->ch_bd->pci_dev, "%s:%d port: %d linestatus: %x\n",
 853		__FILE__, __LINE__, port, linestatus);
 854
 855	ch->ch_cached_lsr |= linestatus;
 856
 857	if (ch->ch_cached_lsr & UART_LSR_DR) {
 858		/* Read data from uart -> queue */
 859		neo_copy_data_from_uart_to_queue(ch);
 860		spin_lock_irqsave(&ch->ch_lock, lock_flags);
 861		jsm_check_queue_flow_control(ch);
 862		spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
 863	}
 864
 865	/*
 866	 * This is a special flag. It indicates that at least 1
 867	 * RX error (parity, framing, or break) has happened.
 868	 * Mark this in our struct, which will tell me that I have
 869	 *to do the special RX+LSR read for this FIFO load.
 870	 */
 871	if (linestatus & UART_17158_RX_FIFO_DATA_ERROR)
 872		jsm_dbg(INTR, &ch->ch_bd->pci_dev,
 873			"%s:%d Port: %d Got an RX error, need to parse LSR\n",
 874			__FILE__, __LINE__, port);
 875
 876	/*
 877	 * The next 3 tests should *NOT* happen, as the above test
 878	 * should encapsulate all 3... At least, thats what Exar says.
 879	 */
 880
 881	if (linestatus & UART_LSR_PE) {
 882		ch->ch_err_parity++;
 883		jsm_dbg(INTR, &ch->ch_bd->pci_dev, "%s:%d Port: %d. PAR ERR!\n",
 884			__FILE__, __LINE__, port);
 885	}
 886
 887	if (linestatus & UART_LSR_FE) {
 888		ch->ch_err_frame++;
 889		jsm_dbg(INTR, &ch->ch_bd->pci_dev, "%s:%d Port: %d. FRM ERR!\n",
 890			__FILE__, __LINE__, port);
 891	}
 892
 893	if (linestatus & UART_LSR_BI) {
 894		ch->ch_err_break++;
 895		jsm_dbg(INTR, &ch->ch_bd->pci_dev,
 896			"%s:%d Port: %d. BRK INTR!\n",
 897			__FILE__, __LINE__, port);
 898	}
 899
 900	if (linestatus & UART_LSR_OE) {
 901		/*
 902		 * Rx Oruns. Exar says that an orun will NOT corrupt
 903		 * the FIFO. It will just replace the holding register
 904		 * with this new data byte. So basically just ignore this.
 905		 * Probably we should eventually have an orun stat in our driver...
 906		 */
 907		ch->ch_err_overrun++;
 908		jsm_dbg(INTR, &ch->ch_bd->pci_dev,
 909			"%s:%d Port: %d. Rx Overrun!\n",
 910			__FILE__, __LINE__, port);
 911	}
 912
 913	if (linestatus & UART_LSR_THRE) {
 914		spin_lock_irqsave(&ch->ch_lock, lock_flags);
 915		ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
 916		spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
 917
 918		/* Transfer data (if any) from Write Queue -> UART. */
 919		neo_copy_data_from_queue_to_uart(ch);
 920	}
 921	else if (linestatus & UART_17158_TX_AND_FIFO_CLR) {
 922		spin_lock_irqsave(&ch->ch_lock, lock_flags);
 923		ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
 924		spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
 925
 926		/* Transfer data (if any) from Write Queue -> UART. */
 927		neo_copy_data_from_queue_to_uart(ch);
 928	}
 929}
 930
 931/*
 932 * neo_param()
 933 * Send any/all changes to the line to the UART.
 934 */
 935static void neo_param(struct jsm_channel *ch)
 936{
 937	u8 lcr = 0;
 938	u8 uart_lcr, ier;
 939	u32 baud;
 940	int quot;
 941	struct jsm_board *bd;
 942
 943	bd = ch->ch_bd;
 944	if (!bd)
 945		return;
 946
 947	/*
 948	 * If baud rate is zero, flush queues, and set mval to drop DTR.
 949	 */
 950	if ((ch->ch_c_cflag & (CBAUD)) == 0) {
 951		ch->ch_r_head = ch->ch_r_tail = 0;
 952		ch->ch_e_head = ch->ch_e_tail = 0;
 953
 954		neo_flush_uart_write(ch);
 955		neo_flush_uart_read(ch);
 956
 957		ch->ch_flags |= (CH_BAUD0);
 958		ch->ch_mostat &= ~(UART_MCR_RTS | UART_MCR_DTR);
 959		neo_assert_modem_signals(ch);
 960		return;
 961
 962	} else {
 963		int i;
 964		unsigned int cflag;
 965		static struct {
 966			unsigned int rate;
 967			unsigned int cflag;
 968		} baud_rates[] = {
 969			{ 921600, B921600 },
 970			{ 460800, B460800 },
 971			{ 230400, B230400 },
 972			{ 115200, B115200 },
 973			{  57600, B57600  },
 974			{  38400, B38400  },
 975			{  19200, B19200  },
 976			{   9600, B9600   },
 977			{   4800, B4800   },
 978			{   2400, B2400   },
 979			{   1200, B1200   },
 980			{    600, B600    },
 981			{    300, B300    },
 982			{    200, B200    },
 983			{    150, B150    },
 984			{    134, B134    },
 985			{    110, B110    },
 986			{     75, B75     },
 987			{     50, B50     },
 988		};
 989
 990		cflag = C_BAUD(ch->uart_port.state->port.tty);
 991		baud = 9600;
 992		for (i = 0; i < ARRAY_SIZE(baud_rates); i++) {
 993			if (baud_rates[i].cflag == cflag) {
 994				baud = baud_rates[i].rate;
 995				break;
 996			}
 997		}
 998
 999		if (ch->ch_flags & CH_BAUD0)
1000			ch->ch_flags &= ~(CH_BAUD0);
1001	}
1002
1003	if (ch->ch_c_cflag & PARENB)
1004		lcr |= UART_LCR_PARITY;
1005
1006	if (!(ch->ch_c_cflag & PARODD))
1007		lcr |= UART_LCR_EPAR;
1008
1009	/*
1010	 * Not all platforms support mark/space parity,
1011	 * so this will hide behind an ifdef.
1012	 */
1013#ifdef CMSPAR
1014	if (ch->ch_c_cflag & CMSPAR)
1015		lcr |= UART_LCR_SPAR;
1016#endif
1017
1018	if (ch->ch_c_cflag & CSTOPB)
1019		lcr |= UART_LCR_STOP;
1020
1021	switch (ch->ch_c_cflag & CSIZE) {
1022	case CS5:
1023		lcr |= UART_LCR_WLEN5;
1024		break;
1025	case CS6:
1026		lcr |= UART_LCR_WLEN6;
1027		break;
1028	case CS7:
1029		lcr |= UART_LCR_WLEN7;
1030		break;
1031	case CS8:
1032	default:
1033		lcr |= UART_LCR_WLEN8;
1034	break;
1035	}
1036
1037	ier = readb(&ch->ch_neo_uart->ier);
1038	uart_lcr = readb(&ch->ch_neo_uart->lcr);
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 */
1107static 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_dbg(INTR, &brd->pci_dev, "%s:%d uart_poll: %x\n",
1131		__FILE__, __LINE__, uart_poll);
1132
1133	if (!uart_poll) {
1134		jsm_dbg(INTR, &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_dbg(INTR, &brd->pci_dev, "%s:%d port: %x type: %x\n",
1161			__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_dbg(INTR, &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 occasionally 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_dbg(INTR, &brd->pci_dev,
1234				"%s:%d Unknown Interrupt type: %x\n",
1235				__FILE__, __LINE__, type);
1236			continue;
1237		}
1238	}
1239
1240	spin_unlock_irqrestore(&brd->bd_intr_lock, lock_flags);
1241
1242	jsm_dbg(INTR, &brd->pci_dev, "finish\n");
1243	return IRQ_HANDLED;
1244}
1245
1246/*
1247 * Neo specific way of turning off the receiver.
1248 * Used as a way to enforce queue flow control when in
1249 * hardware flow control mode.
1250 */
1251static void neo_disable_receiver(struct jsm_channel *ch)
1252{
1253	u8 tmp = readb(&ch->ch_neo_uart->ier);
1254	tmp &= ~(UART_IER_RDI);
1255	writeb(tmp, &ch->ch_neo_uart->ier);
1256
1257	/* flush write operation */
1258	neo_pci_posting_flush(ch->ch_bd);
1259}
1260
1261
1262/*
1263 * Neo specific way of turning on the receiver.
1264 * Used as a way to un-enforce queue flow control when in
1265 * hardware flow control mode.
1266 */
1267static void neo_enable_receiver(struct jsm_channel *ch)
1268{
1269	u8 tmp = readb(&ch->ch_neo_uart->ier);
1270	tmp |= (UART_IER_RDI);
1271	writeb(tmp, &ch->ch_neo_uart->ier);
1272
1273	/* flush write operation */
1274	neo_pci_posting_flush(ch->ch_bd);
1275}
1276
1277static void neo_send_start_character(struct jsm_channel *ch)
1278{
1279	if (!ch)
1280		return;
1281
1282	if (ch->ch_startc != __DISABLED_CHAR) {
1283		ch->ch_xon_sends++;
1284		writeb(ch->ch_startc, &ch->ch_neo_uart->txrx);
1285
1286		/* flush write operation */
1287		neo_pci_posting_flush(ch->ch_bd);
1288	}
1289}
1290
1291static void neo_send_stop_character(struct jsm_channel *ch)
1292{
1293	if (!ch)
1294		return;
1295
1296	if (ch->ch_stopc != __DISABLED_CHAR) {
1297		ch->ch_xoff_sends++;
1298		writeb(ch->ch_stopc, &ch->ch_neo_uart->txrx);
1299
1300		/* flush write operation */
1301		neo_pci_posting_flush(ch->ch_bd);
1302	}
1303}
1304
1305/*
1306 * neo_uart_init
1307 */
1308static void neo_uart_init(struct jsm_channel *ch)
1309{
1310	writeb(0, &ch->ch_neo_uart->ier);
1311	writeb(0, &ch->ch_neo_uart->efr);
1312	writeb(UART_EFR_ECB, &ch->ch_neo_uart->efr);
1313
1314	/* Clear out UART and FIFO */
1315	readb(&ch->ch_neo_uart->txrx);
1316	writeb((UART_FCR_ENABLE_FIFO|UART_FCR_CLEAR_RCVR|UART_FCR_CLEAR_XMIT), &ch->ch_neo_uart->isr_fcr);
1317	readb(&ch->ch_neo_uart->lsr);
1318	readb(&ch->ch_neo_uart->msr);
1319
1320	ch->ch_flags |= CH_FIFO_ENABLED;
1321
1322	/* Assert any signals we want up */
1323	writeb(ch->ch_mostat, &ch->ch_neo_uart->mcr);
1324}
1325
1326/*
1327 * Make the UART completely turn off.
1328 */
1329static void neo_uart_off(struct jsm_channel *ch)
1330{
1331	/* Turn off UART enhanced bits */
1332	writeb(0, &ch->ch_neo_uart->efr);
1333
1334	/* Stop all interrupts from occurring. */
1335	writeb(0, &ch->ch_neo_uart->ier);
1336}
1337
1338static u32 neo_get_uart_bytes_left(struct jsm_channel *ch)
1339{
1340	u8 left = 0;
1341	u8 lsr = readb(&ch->ch_neo_uart->lsr);
1342
1343	/* We must cache the LSR as some of the bits get reset once read... */
1344	ch->ch_cached_lsr |= lsr;
1345
1346	/* Determine whether the Transmitter is empty or not */
1347	if (!(lsr & UART_LSR_TEMT))
1348		left = 1;
1349	else {
1350		ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
1351		left = 0;
1352	}
1353
1354	return left;
1355}
1356
1357/* Channel lock MUST be held by the calling function! */
1358static void neo_send_break(struct jsm_channel *ch)
1359{
1360	/*
1361	 * Set the time we should stop sending the break.
1362	 * If we are already sending a break, toss away the existing
1363	 * time to stop, and use this new value instead.
1364	 */
1365
1366	/* Tell the UART to start sending the break */
1367	if (!(ch->ch_flags & CH_BREAK_SENDING)) {
1368		u8 temp = readb(&ch->ch_neo_uart->lcr);
1369		writeb((temp | UART_LCR_SBC), &ch->ch_neo_uart->lcr);
1370		ch->ch_flags |= (CH_BREAK_SENDING);
1371
1372		/* flush write operation */
1373		neo_pci_posting_flush(ch->ch_bd);
1374	}
1375}
1376
1377/*
1378 * neo_send_immediate_char.
1379 *
1380 * Sends a specific character as soon as possible to the UART,
1381 * jumping over any bytes that might be in the write queue.
1382 *
1383 * The channel lock MUST be held by the calling function.
1384 */
1385static void neo_send_immediate_char(struct jsm_channel *ch, unsigned char c)
1386{
1387	if (!ch)
1388		return;
1389
1390	writeb(c, &ch->ch_neo_uart->txrx);
1391
1392	/* flush write operation */
1393	neo_pci_posting_flush(ch->ch_bd);
1394}
1395
1396struct board_ops jsm_neo_ops = {
1397	.intr				= neo_intr,
1398	.uart_init			= neo_uart_init,
1399	.uart_off			= neo_uart_off,
1400	.param				= neo_param,
1401	.assert_modem_signals		= neo_assert_modem_signals,
1402	.flush_uart_write		= neo_flush_uart_write,
1403	.flush_uart_read		= neo_flush_uart_read,
1404	.disable_receiver		= neo_disable_receiver,
1405	.enable_receiver		= neo_enable_receiver,
1406	.send_break			= neo_send_break,
1407	.clear_break			= neo_clear_break,
1408	.send_start_character		= neo_send_start_character,
1409	.send_stop_character		= neo_send_stop_character,
1410	.copy_data_from_queue_to_uart	= neo_copy_data_from_queue_to_uart,
1411	.get_uart_bytes_left		= neo_get_uart_bytes_left,
1412	.send_immediate_char		= neo_send_immediate_char
1413};