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
34static 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 */
44static inline void neo_pci_posting_flush(struct jsm_board *bd)
45{
46      readb(bd->re_map_membase + 0x8D);
47}
48
49static 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
80static 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
120static 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
157static 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
195static 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
234static 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
272static 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
289static 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 guaranteed
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
491static 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	struct circ_buf *circ;
500
501	if (!ch)
502		return;
503
504	circ = &ch->uart_port.state->xmit;
505
506	/* No data to write to the UART */
507	if (uart_circ_empty(circ))
508		return;
509
510	/* If port is "stopped", don't send any data to the UART */
511	if ((ch->ch_flags & CH_STOP) || (ch->ch_flags & CH_BREAK_SENDING))
512		return;
513	/*
514	 * If FIFOs are disabled. Send data directly to txrx register
515	 */
516	if (!(ch->ch_flags & CH_FIFO_ENABLED)) {
517		u8 lsrbits = readb(&ch->ch_neo_uart->lsr);
518
519		ch->ch_cached_lsr |= lsrbits;
520		if (ch->ch_cached_lsr & UART_LSR_THRE) {
521			ch->ch_cached_lsr &= ~(UART_LSR_THRE);
522
523			writeb(circ->buf[circ->tail], &ch->ch_neo_uart->txrx);
524			jsm_printk(WRITE, INFO, &ch->ch_bd->pci_dev,
525					"Tx data: %x\n", circ->buf[circ->tail]);
526			circ->tail = (circ->tail + 1) & (UART_XMIT_SIZE - 1);
527			ch->ch_txcount++;
528		}
529		return;
530	}
531
532	/*
533	 * We have to do it this way, because of the EXAR TXFIFO count bug.
534	 */
535	if (!(ch->ch_flags & (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM)))
536		return;
537
538	n = UART_17158_TX_FIFOSIZE - ch->ch_t_tlevel;
539
540	/* cache head and tail of queue */
541	head = circ->head & (UART_XMIT_SIZE - 1);
542	tail = circ->tail & (UART_XMIT_SIZE - 1);
543	qlen = uart_circ_chars_pending(circ);
544
545	/* Find minimum of the FIFO space, versus queue length */
546	n = min(n, qlen);
547
548	while (n > 0) {
549
550		s = ((head >= tail) ? head : UART_XMIT_SIZE) - tail;
551		s = min(s, n);
552
553		if (s <= 0)
554			break;
555
556		memcpy_toio(&ch->ch_neo_uart->txrxburst, circ->buf + tail, s);
557		/* Add and flip queue if needed */
558		tail = (tail + s) & (UART_XMIT_SIZE - 1);
559		n -= s;
560		ch->ch_txcount += s;
561		len_written += s;
562	}
563
564	/* Update the final tail */
565	circ->tail = tail & (UART_XMIT_SIZE - 1);
566
567	if (len_written >= ch->ch_t_tlevel)
568		ch->ch_flags &= ~(CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
569
570	if (uart_circ_empty(circ))
571		uart_write_wakeup(&ch->uart_port);
572}
573
574static void neo_parse_modem(struct jsm_channel *ch, u8 signals)
575{
576	u8 msignals = signals;
577
578	jsm_printk(MSIGS, INFO, &ch->ch_bd->pci_dev,
579			"neo_parse_modem: port: %d msignals: %x\n", ch->ch_portnum, msignals);
580
581	/* Scrub off lower bits. They signify delta's, which I don't care about */
582	/* Keep DDCD and DDSR though */
583	msignals &= 0xf8;
584
585	if (msignals & UART_MSR_DDCD)
586		uart_handle_dcd_change(&ch->uart_port, msignals & UART_MSR_DCD);
587	if (msignals & UART_MSR_DDSR)
588		uart_handle_cts_change(&ch->uart_port, msignals & UART_MSR_CTS);
589	if (msignals & UART_MSR_DCD)
590		ch->ch_mistat |= UART_MSR_DCD;
591	else
592		ch->ch_mistat &= ~UART_MSR_DCD;
593
594	if (msignals & UART_MSR_DSR)
595		ch->ch_mistat |= UART_MSR_DSR;
596	else
597		ch->ch_mistat &= ~UART_MSR_DSR;
598
599	if (msignals & UART_MSR_RI)
600		ch->ch_mistat |= UART_MSR_RI;
601	else
602		ch->ch_mistat &= ~UART_MSR_RI;
603
604	if (msignals & UART_MSR_CTS)
605		ch->ch_mistat |= UART_MSR_CTS;
606	else
607		ch->ch_mistat &= ~UART_MSR_CTS;
608
609	jsm_printk(MSIGS, INFO, &ch->ch_bd->pci_dev,
610			"Port: %d DTR: %d RTS: %d CTS: %d DSR: %d " "RI: %d CD: %d\n",
611		ch->ch_portnum,
612		!!((ch->ch_mistat | ch->ch_mostat) & UART_MCR_DTR),
613		!!((ch->ch_mistat | ch->ch_mostat) & UART_MCR_RTS),
614		!!((ch->ch_mistat | ch->ch_mostat) & UART_MSR_CTS),
615		!!((ch->ch_mistat | ch->ch_mostat) & UART_MSR_DSR),
616		!!((ch->ch_mistat | ch->ch_mostat) & UART_MSR_RI),
617		!!((ch->ch_mistat | ch->ch_mostat) & UART_MSR_DCD));
618}
619
620/* Make the UART raise any of the output signals we want up */
621static void neo_assert_modem_signals(struct jsm_channel *ch)
622{
623	if (!ch)
624		return;
625
626	writeb(ch->ch_mostat, &ch->ch_neo_uart->mcr);
627
628	/* flush write operation */
629	neo_pci_posting_flush(ch->ch_bd);
630}
631
632/*
633 * Flush the WRITE FIFO on the Neo.
634 *
635 * NOTE: Channel lock MUST be held before calling this function!
636 */
637static void neo_flush_uart_write(struct jsm_channel *ch)
638{
639	u8 tmp = 0;
640	int i = 0;
641
642	if (!ch)
643		return;
644
645	writeb((UART_FCR_ENABLE_FIFO | UART_FCR_CLEAR_XMIT), &ch->ch_neo_uart->isr_fcr);
646
647	for (i = 0; i < 10; i++) {
648
649		/* Check to see if the UART feels it completely flushed the FIFO. */
650		tmp = readb(&ch->ch_neo_uart->isr_fcr);
651		if (tmp & 4) {
652			jsm_printk(IOCTL, INFO, &ch->ch_bd->pci_dev,
653					"Still flushing TX UART... i: %d\n", i);
654			udelay(10);
655		}
656		else
657			break;
658	}
659
660	ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
661}
662
663
664/*
665 * Flush the READ FIFO on the Neo.
666 *
667 * NOTE: Channel lock MUST be held before calling this function!
668 */
669static void neo_flush_uart_read(struct jsm_channel *ch)
670{
671	u8 tmp = 0;
672	int i = 0;
673
674	if (!ch)
675		return;
676
677	writeb((UART_FCR_ENABLE_FIFO | UART_FCR_CLEAR_RCVR), &ch->ch_neo_uart->isr_fcr);
678
679	for (i = 0; i < 10; i++) {
680
681		/* Check to see if the UART feels it completely flushed the FIFO. */
682		tmp = readb(&ch->ch_neo_uart->isr_fcr);
683		if (tmp & 2) {
684			jsm_printk(IOCTL, INFO, &ch->ch_bd->pci_dev,
685					"Still flushing RX UART... i: %d\n", i);
686			udelay(10);
687		}
688		else
689			break;
690	}
691}
692
693/*
694 * No locks are assumed to be held when calling this function.
695 */
696static void neo_clear_break(struct jsm_channel *ch, int force)
697{
698	unsigned long lock_flags;
699
700	spin_lock_irqsave(&ch->ch_lock, lock_flags);
701
702	/* Turn break off, and unset some variables */
703	if (ch->ch_flags & CH_BREAK_SENDING) {
704		u8 temp = readb(&ch->ch_neo_uart->lcr);
705		writeb((temp & ~UART_LCR_SBC), &ch->ch_neo_uart->lcr);
706
707		ch->ch_flags &= ~(CH_BREAK_SENDING);
708		jsm_printk(IOCTL, INFO, &ch->ch_bd->pci_dev,
709				"clear break Finishing UART_LCR_SBC! finished: %lx\n", jiffies);
710
711		/* flush write operation */
712		neo_pci_posting_flush(ch->ch_bd);
713	}
714	spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
715}
716
717/*
718 * Parse the ISR register.
719 */
720static inline void neo_parse_isr(struct jsm_board *brd, u32 port)
721{
722	struct jsm_channel *ch;
723	u8 isr;
724	u8 cause;
725	unsigned long lock_flags;
726
727	if (!brd)
728		return;
729
730	if (port > brd->maxports)
731		return;
732
733	ch = brd->channels[port];
734	if (!ch)
735		return;
736
737	/* Here we try to figure out what caused the interrupt to happen */
738	while (1) {
739
740		isr = readb(&ch->ch_neo_uart->isr_fcr);
741
742		/* Bail if no pending interrupt */
743		if (isr & UART_IIR_NO_INT)
744			break;
745
746		/*
747		 * Yank off the upper 2 bits, which just show that the FIFO's are enabled.
748		 */
749		isr &= ~(UART_17158_IIR_FIFO_ENABLED);
750
751		jsm_printk(INTR, INFO, &ch->ch_bd->pci_dev,
752				"%s:%d isr: %x\n", __FILE__, __LINE__, isr);
753
754		if (isr & (UART_17158_IIR_RDI_TIMEOUT | UART_IIR_RDI)) {
755			/* Read data from uart -> queue */
756			neo_copy_data_from_uart_to_queue(ch);
757
758			/* Call our tty layer to enforce queue flow control if needed. */
759			spin_lock_irqsave(&ch->ch_lock, lock_flags);
760			jsm_check_queue_flow_control(ch);
761			spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
762		}
763
764		if (isr & UART_IIR_THRI) {
765			/* Transfer data (if any) from Write Queue -> UART. */
766			spin_lock_irqsave(&ch->ch_lock, lock_flags);
767			ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
768			spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
769			neo_copy_data_from_queue_to_uart(ch);
770		}
771
772		if (isr & UART_17158_IIR_XONXOFF) {
773			cause = readb(&ch->ch_neo_uart->xoffchar1);
774
775			jsm_printk(INTR, INFO, &ch->ch_bd->pci_dev,
776					"Port %d. Got ISR_XONXOFF: cause:%x\n", port, cause);
777
778			/*
779			 * Since the UART detected either an XON or
780			 * XOFF match, we need to figure out which
781			 * one it was, so we can suspend or resume data flow.
782			 */
783			spin_lock_irqsave(&ch->ch_lock, lock_flags);
784			if (cause == UART_17158_XON_DETECT) {
785				/* Is output stopped right now, if so, resume it */
786				if (brd->channels[port]->ch_flags & CH_STOP) {
787					ch->ch_flags &= ~(CH_STOP);
788				}
789				jsm_printk(INTR, INFO, &ch->ch_bd->pci_dev,
790						"Port %d. XON detected in incoming data\n", port);
791			}
792			else if (cause == UART_17158_XOFF_DETECT) {
793				if (!(brd->channels[port]->ch_flags & CH_STOP)) {
794					ch->ch_flags |= CH_STOP;
795					jsm_printk(INTR, INFO, &ch->ch_bd->pci_dev,
796							"Setting CH_STOP\n");
797				}
798				jsm_printk(INTR, INFO, &ch->ch_bd->pci_dev,
799						"Port: %d. XOFF detected in incoming data\n", 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_printk(INTR, INFO, &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_printk(INTR, INFO, &ch->ch_bd->pci_dev,
853			"%s:%d port: %d linestatus: %x\n", __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_printk(INTR, DEBUG, &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_printk(INTR, DEBUG, &ch->ch_bd->pci_dev,
884			"%s:%d Port: %d. PAR ERR!\n", __FILE__, __LINE__, port);
885	}
886
887	if (linestatus & UART_LSR_FE) {
888		ch->ch_err_frame++;
889		jsm_printk(INTR, DEBUG, &ch->ch_bd->pci_dev,
890			"%s:%d Port: %d. FRM ERR!\n", __FILE__, __LINE__, port);
891	}
892
893	if (linestatus & UART_LSR_BI) {
894		ch->ch_err_break++;
895		jsm_printk(INTR, DEBUG, &ch->ch_bd->pci_dev,
896			"%s:%d Port: %d. BRK INTR!\n", __FILE__, __LINE__, port);
897	}
898
899	if (linestatus & UART_LSR_OE) {
900		/*
901		 * Rx Oruns. Exar says that an orun will NOT corrupt
902		 * the FIFO. It will just replace the holding register
903		 * with this new data byte. So basically just ignore this.
904		 * Probably we should eventually have an orun stat in our driver...
905		 */
906		ch->ch_err_overrun++;
907		jsm_printk(INTR, DEBUG, &ch->ch_bd->pci_dev,
908			"%s:%d Port: %d. Rx Overrun!\n", __FILE__, __LINE__, port);
909	}
910
911	if (linestatus & UART_LSR_THRE) {
912		spin_lock_irqsave(&ch->ch_lock, lock_flags);
913		ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
914		spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
915
916		/* Transfer data (if any) from Write Queue -> UART. */
917		neo_copy_data_from_queue_to_uart(ch);
918	}
919	else if (linestatus & UART_17158_TX_AND_FIFO_CLR) {
920		spin_lock_irqsave(&ch->ch_lock, lock_flags);
921		ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);
922		spin_unlock_irqrestore(&ch->ch_lock, lock_flags);
923
924		/* Transfer data (if any) from Write Queue -> UART. */
925		neo_copy_data_from_queue_to_uart(ch);
926	}
927}
928
929/*
930 * neo_param()
931 * Send any/all changes to the line to the UART.
932 */
933static void neo_param(struct jsm_channel *ch)
934{
935	u8 lcr = 0;
936	u8 uart_lcr, ier;
937	u32 baud;
938	int quot;
939	struct jsm_board *bd;
940
941	bd = ch->ch_bd;
942	if (!bd)
943		return;
944
945	/*
946	 * If baud rate is zero, flush queues, and set mval to drop DTR.
947	 */
948	if ((ch->ch_c_cflag & (CBAUD)) == 0) {
949		ch->ch_r_head = ch->ch_r_tail = 0;
950		ch->ch_e_head = ch->ch_e_tail = 0;
951
952		neo_flush_uart_write(ch);
953		neo_flush_uart_read(ch);
954
955		ch->ch_flags |= (CH_BAUD0);
956		ch->ch_mostat &= ~(UART_MCR_RTS | UART_MCR_DTR);
957		neo_assert_modem_signals(ch);
958		return;
959
960	} else {
961		int i;
962		unsigned int cflag;
963		static struct {
964			unsigned int rate;
965			unsigned int cflag;
966		} baud_rates[] = {
967			{ 921600, B921600 },
968			{ 460800, B460800 },
969			{ 230400, B230400 },
970			{ 115200, B115200 },
971			{  57600, B57600  },
972			{  38400, B38400  },
973			{  19200, B19200  },
974			{   9600, B9600   },
975			{   4800, B4800   },
976			{   2400, B2400   },
977			{   1200, B1200   },
978			{    600, B600    },
979			{    300, B300    },
980			{    200, B200    },
981			{    150, B150    },
982			{    134, B134    },
983			{    110, B110    },
984			{     75, B75     },
985			{     50, B50     },
986		};
987
988		cflag = C_BAUD(ch->uart_port.state->port.tty);
989		baud = 9600;
990		for (i = 0; i < ARRAY_SIZE(baud_rates); i++) {
991			if (baud_rates[i].cflag == cflag) {
992				baud = baud_rates[i].rate;
993				break;
994			}
995		}
996
997		if (ch->ch_flags & CH_BAUD0)
998			ch->ch_flags &= ~(CH_BAUD0);
999	}
1000
1001	if (ch->ch_c_cflag & PARENB)
1002		lcr |= UART_LCR_PARITY;
1003
1004	if (!(ch->ch_c_cflag & PARODD))
1005		lcr |= UART_LCR_EPAR;
1006
1007	/*
1008	 * Not all platforms support mark/space parity,
1009	 * so this will hide behind an ifdef.
1010	 */
1011#ifdef CMSPAR
1012	if (ch->ch_c_cflag & CMSPAR)
1013		lcr |= UART_LCR_SPAR;
1014#endif
1015
1016	if (ch->ch_c_cflag & CSTOPB)
1017		lcr |= UART_LCR_STOP;
1018
1019	switch (ch->ch_c_cflag & CSIZE) {
1020		case CS5:
1021			lcr |= UART_LCR_WLEN5;
1022			break;
1023		case CS6:
1024			lcr |= UART_LCR_WLEN6;
1025			break;
1026		case CS7:
1027			lcr |= UART_LCR_WLEN7;
1028			break;
1029		case CS8:
1030		default:
1031			lcr |= UART_LCR_WLEN8;
1032		break;
1033	}
1034
1035	ier = readb(&ch->ch_neo_uart->ier);
1036	uart_lcr = readb(&ch->ch_neo_uart->lcr);
1037
1038	if (baud == 0)
1039		baud = 9600;
1040
1041	quot = ch->ch_bd->bd_dividend / baud;
1042
1043	if (quot != 0) {
1044		writeb(UART_LCR_DLAB, &ch->ch_neo_uart->lcr);
1045		writeb((quot & 0xff), &ch->ch_neo_uart->txrx);
1046		writeb((quot >> 8), &ch->ch_neo_uart->ier);
1047		writeb(lcr, &ch->ch_neo_uart->lcr);
1048	}
1049
1050	if (uart_lcr != lcr)
1051		writeb(lcr, &ch->ch_neo_uart->lcr);
1052
1053	if (ch->ch_c_cflag & CREAD)
1054		ier |= (UART_IER_RDI | UART_IER_RLSI);
1055
1056	ier |= (UART_IER_THRI | UART_IER_MSI);
1057
1058	writeb(ier, &ch->ch_neo_uart->ier);
1059
1060	/* Set new start/stop chars */
1061	neo_set_new_start_stop_chars(ch);
1062
1063	if (ch->ch_c_cflag & CRTSCTS)
1064		neo_set_cts_flow_control(ch);
1065	else if (ch->ch_c_iflag & IXON) {
1066		/* If start/stop is set to disable, then we should disable flow control */
1067		if ((ch->ch_startc == __DISABLED_CHAR) || (ch->ch_stopc == __DISABLED_CHAR))
1068			neo_set_no_output_flow_control(ch);
1069		else
1070			neo_set_ixon_flow_control(ch);
1071	}
1072	else
1073		neo_set_no_output_flow_control(ch);
1074
1075	if (ch->ch_c_cflag & CRTSCTS)
1076		neo_set_rts_flow_control(ch);
1077	else if (ch->ch_c_iflag & IXOFF) {
1078		/* If start/stop is set to disable, then we should disable flow control */
1079		if ((ch->ch_startc == __DISABLED_CHAR) || (ch->ch_stopc == __DISABLED_CHAR))
1080			neo_set_no_input_flow_control(ch);
1081		else
1082			neo_set_ixoff_flow_control(ch);
1083	}
1084	else
1085		neo_set_no_input_flow_control(ch);
1086	/*
1087	 * Adjust the RX FIFO Trigger level if baud is less than 9600.
1088	 * Not exactly elegant, but this is needed because of the Exar chip's
1089	 * delay on firing off the RX FIFO interrupt on slower baud rates.
1090	 */
1091	if (baud < 9600) {
1092		writeb(1, &ch->ch_neo_uart->rfifo);
1093		ch->ch_r_tlevel = 1;
1094	}
1095
1096	neo_assert_modem_signals(ch);
1097
1098	/* Get current status of the modem signals now */
1099	neo_parse_modem(ch, readb(&ch->ch_neo_uart->msr));
1100	return;
1101}
1102
1103/*
1104 * jsm_neo_intr()
1105 *
1106 * Neo specific interrupt handler.
1107 */
1108static irqreturn_t neo_intr(int irq, void *voidbrd)
1109{
1110	struct jsm_board *brd = voidbrd;
1111	struct jsm_channel *ch;
1112	int port = 0;
1113	int type = 0;
1114	int current_port;
1115	u32 tmp;
1116	u32 uart_poll;
1117	unsigned long lock_flags;
1118	unsigned long lock_flags2;
1119	int outofloop_count = 0;
1120
1121	/* Lock out the slow poller from running on this board. */
1122	spin_lock_irqsave(&brd->bd_intr_lock, lock_flags);
1123
1124	/*
1125	 * Read in "extended" IRQ information from the 32bit Neo register.
1126	 * Bits 0-7: What port triggered the interrupt.
1127	 * Bits 8-31: Each 3bits indicate what type of interrupt occurred.
1128	 */
1129	uart_poll = readl(brd->re_map_membase + UART_17158_POLL_ADDR_OFFSET);
1130
1131	jsm_printk(INTR, INFO, &brd->pci_dev,
1132		"%s:%d uart_poll: %x\n", __FILE__, __LINE__, uart_poll);
1133
1134	if (!uart_poll) {
1135		jsm_printk(INTR, INFO, &brd->pci_dev,
1136			"Kernel interrupted to me, but no pending interrupts...\n");
1137		spin_unlock_irqrestore(&brd->bd_intr_lock, lock_flags);
1138		return IRQ_NONE;
1139	}
1140
1141	/* At this point, we have at least SOMETHING to service, dig further... */
1142
1143	current_port = 0;
1144
1145	/* Loop on each port */
1146	while (((uart_poll & 0xff) != 0) && (outofloop_count < 0xff)){
1147
1148		tmp = uart_poll;
1149		outofloop_count++;
1150
1151		/* Check current port to see if it has interrupt pending */
1152		if ((tmp & jsm_offset_table[current_port]) != 0) {
1153			port = current_port;
1154			type = tmp >> (8 + (port * 3));
1155			type &= 0x7;
1156		} else {
1157			current_port++;
1158			continue;
1159		}
1160
1161		jsm_printk(INTR, INFO, &brd->pci_dev,
1162		"%s:%d port: %x type: %x\n", __FILE__, __LINE__, port, type);
1163
1164		/* Remove this port + type from uart_poll */
1165		uart_poll &= ~(jsm_offset_table[port]);
1166
1167		if (!type) {
1168			/* If no type, just ignore it, and move onto next port */
1169			jsm_printk(INTR, ERR, &brd->pci_dev,
1170				"Interrupt with no type! port: %d\n", port);
1171			continue;
1172		}
1173
1174		/* Switch on type of interrupt we have */
1175		switch (type) {
1176
1177		case UART_17158_RXRDY_TIMEOUT:
1178			/*
1179			 * RXRDY Time-out is cleared by reading data in the
1180			* RX FIFO until it falls below the trigger level.
1181			 */
1182
1183			/* Verify the port is in range. */
1184			if (port > brd->nasync)
1185				continue;
1186
1187			ch = brd->channels[port];
1188			neo_copy_data_from_uart_to_queue(ch);
1189
1190			/* Call our tty layer to enforce queue flow control if needed. */
1191			spin_lock_irqsave(&ch->ch_lock, lock_flags2);
1192			jsm_check_queue_flow_control(ch);
1193			spin_unlock_irqrestore(&ch->ch_lock, lock_flags2);
1194
1195			continue;
1196
1197		case UART_17158_RX_LINE_STATUS:
1198			/*
1199			 * RXRDY and RX LINE Status (logic OR of LSR[4:1])
1200			 */
1201			neo_parse_lsr(brd, port);
1202			continue;
1203
1204		case UART_17158_TXRDY:
1205			/*
1206			 * TXRDY interrupt clears after reading ISR register for the UART channel.
1207			 */
1208
1209			/*
1210			 * Yes, this is odd...
1211			 * Why would I check EVERY possibility of type of
1212			 * interrupt, when we know its TXRDY???
1213			 * Becuz for some reason, even tho we got triggered for TXRDY,
1214			 * it seems to be occasionally wrong. Instead of TX, which
1215			 * it should be, I was getting things like RXDY too. Weird.
1216			 */
1217			neo_parse_isr(brd, port);
1218			continue;
1219
1220		case UART_17158_MSR:
1221			/*
1222			 * MSR or flow control was seen.
1223			 */
1224			neo_parse_isr(brd, port);
1225			continue;
1226
1227		default:
1228			/*
1229			 * The UART triggered us with a bogus interrupt type.
1230			 * It appears the Exar chip, when REALLY bogged down, will throw
1231			 * these once and awhile.
1232			 * Its harmless, just ignore it and move on.
1233			 */
1234			jsm_printk(INTR, ERR, &brd->pci_dev,
1235				"%s:%d Unknown Interrupt type: %x\n", __FILE__, __LINE__, type);
1236			continue;
1237		}
1238	}
1239
1240	spin_unlock_irqrestore(&brd->bd_intr_lock, lock_flags);
1241
1242	jsm_printk(INTR, INFO, &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};
1414