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  • only in /asuswrt-rt-n18u-9.0.0.4.380.2695/release/src-rt-6.x.4708/linux/linux-2.6/drivers/char/rio/
1/*
2** -----------------------------------------------------------------------------
3**
4**  Perle Specialix driver for Linux
5**  Ported from existing RIO Driver for SCO sources.
6 *
7 *  (C) 1990 - 2000 Specialix International Ltd., Byfleet, Surrey, UK.
8 *
9 *      This program is free software; you can redistribute it and/or modify
10 *      it under the terms of the GNU General Public License as published by
11 *      the Free Software Foundation; either version 2 of the License, or
12 *      (at your option) any later version.
13 *
14 *      This program is distributed in the hope that it will be useful,
15 *      but WITHOUT ANY WARRANTY; without even the implied warranty of
16 *      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17 *      GNU General Public License for more details.
18 *
19 *      You should have received a copy of the GNU General Public License
20 *      along with this program; if not, write to the Free Software
21 *      Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
22**
23**	Module		: riointr.c
24**	SID		: 1.2
25**	Last Modified	: 11/6/98 10:33:44
26**	Retrieved	: 11/6/98 10:33:49
27**
28**  ident @(#)riointr.c	1.2
29**
30** -----------------------------------------------------------------------------
31*/
32
33#include <linux/module.h>
34#include <linux/errno.h>
35#include <linux/tty.h>
36#include <linux/tty_flip.h>
37#include <asm/io.h>
38#include <asm/system.h>
39#include <asm/string.h>
40#include <asm/uaccess.h>
41
42#include <linux/termios.h>
43#include <linux/serial.h>
44
45#include <linux/generic_serial.h>
46
47#include <linux/delay.h>
48
49#include "linux_compat.h"
50#include "rio_linux.h"
51#include "pkt.h"
52#include "daemon.h"
53#include "rio.h"
54#include "riospace.h"
55#include "cmdpkt.h"
56#include "map.h"
57#include "rup.h"
58#include "port.h"
59#include "riodrvr.h"
60#include "rioinfo.h"
61#include "func.h"
62#include "errors.h"
63#include "pci.h"
64
65#include "parmmap.h"
66#include "unixrup.h"
67#include "board.h"
68#include "host.h"
69#include "phb.h"
70#include "link.h"
71#include "cmdblk.h"
72#include "route.h"
73#include "cirrus.h"
74#include "rioioctl.h"
75
76
77static void RIOReceive(struct rio_info *, struct Port *);
78
79
80static char *firstchars(char *p, int nch)
81{
82	static char buf[2][128];
83	static int t = 0;
84	t = !t;
85	memcpy(buf[t], p, nch);
86	buf[t][nch] = 0;
87	return buf[t];
88}
89
90
91#define	INCR( P, I )	((P) = (((P)+(I)) & p->RIOBufferMask))
92/* Enable and start the transmission of packets */
93void RIOTxEnable(char *en)
94{
95	struct Port *PortP;
96	struct rio_info *p;
97	struct tty_struct *tty;
98	int c;
99	struct PKT __iomem *PacketP;
100	unsigned long flags;
101
102	PortP = (struct Port *) en;
103	p = (struct rio_info *) PortP->p;
104	tty = PortP->gs.port.tty;
105
106
107	rio_dprintk(RIO_DEBUG_INTR, "tx port %d: %d chars queued.\n", PortP->PortNum, PortP->gs.xmit_cnt);
108
109	if (!PortP->gs.xmit_cnt)
110		return;
111
112
113	/* This routine is an order of magnitude simpler than the specialix
114	   version. One of the disadvantages is that this version will send
115	   an incomplete packet (usually 64 bytes instead of 72) once for
116	   every 4k worth of data. Let's just say that this won't influence
117	   performance significantly..... */
118
119	rio_spin_lock_irqsave(&PortP->portSem, flags);
120
121	while (can_add_transmit(&PacketP, PortP)) {
122		c = PortP->gs.xmit_cnt;
123		if (c > PKT_MAX_DATA_LEN)
124			c = PKT_MAX_DATA_LEN;
125
126		/* Don't copy past the end of the source buffer */
127		if (c > SERIAL_XMIT_SIZE - PortP->gs.xmit_tail)
128			c = SERIAL_XMIT_SIZE - PortP->gs.xmit_tail;
129
130		{
131			int t;
132			t = (c > 10) ? 10 : c;
133
134			rio_dprintk(RIO_DEBUG_INTR, "rio: tx port %d: copying %d chars: %s - %s\n", PortP->PortNum, c, firstchars(PortP->gs.xmit_buf + PortP->gs.xmit_tail, t), firstchars(PortP->gs.xmit_buf + PortP->gs.xmit_tail + c - t, t));
135		}
136		/* If for one reason or another, we can't copy more data,
137		   we're done! */
138		if (c == 0)
139			break;
140
141		rio_memcpy_toio(PortP->HostP->Caddr, PacketP->data, PortP->gs.xmit_buf + PortP->gs.xmit_tail, c);
142		/*    udelay (1); */
143
144		writeb(c, &(PacketP->len));
145		if (!(PortP->State & RIO_DELETED)) {
146			add_transmit(PortP);
147			/*
148			 ** Count chars tx'd for port statistics reporting
149			 */
150			if (PortP->statsGather)
151				PortP->txchars += c;
152		}
153		PortP->gs.xmit_tail = (PortP->gs.xmit_tail + c) & (SERIAL_XMIT_SIZE - 1);
154		PortP->gs.xmit_cnt -= c;
155	}
156
157	rio_spin_unlock_irqrestore(&PortP->portSem, flags);
158
159	if (PortP->gs.xmit_cnt <= (PortP->gs.wakeup_chars + 2 * PKT_MAX_DATA_LEN))
160		tty_wakeup(PortP->gs.port.tty);
161
162}
163
164
165/*
166** RIO Host Service routine. Does all the work traditionally associated with an
167** interrupt.
168*/
169static int RupIntr;
170static int RxIntr;
171static int TxIntr;
172
173void RIOServiceHost(struct rio_info *p, struct Host *HostP)
174{
175	rio_spin_lock(&HostP->HostLock);
176	if ((HostP->Flags & RUN_STATE) != RC_RUNNING) {
177		static int t = 0;
178		rio_spin_unlock(&HostP->HostLock);
179		if ((t++ % 200) == 0)
180			rio_dprintk(RIO_DEBUG_INTR, "Interrupt but host not running. flags=%x.\n", (int) HostP->Flags);
181		return;
182	}
183	rio_spin_unlock(&HostP->HostLock);
184
185	if (readw(&HostP->ParmMapP->rup_intr)) {
186		writew(0, &HostP->ParmMapP->rup_intr);
187		p->RIORupCount++;
188		RupIntr++;
189		rio_dprintk(RIO_DEBUG_INTR, "rio: RUP interrupt on host %Zd\n", HostP - p->RIOHosts);
190		RIOPollHostCommands(p, HostP);
191	}
192
193	if (readw(&HostP->ParmMapP->rx_intr)) {
194		int port;
195
196		writew(0, &HostP->ParmMapP->rx_intr);
197		p->RIORxCount++;
198		RxIntr++;
199
200		rio_dprintk(RIO_DEBUG_INTR, "rio: RX interrupt on host %Zd\n", HostP - p->RIOHosts);
201		/*
202		 ** Loop through every port. If the port is mapped into
203		 ** the system ( i.e. has /dev/ttyXXXX associated ) then it is
204		 ** worth checking. If the port isn't open, grab any packets
205		 ** hanging on its receive queue and stuff them on the free
206		 ** list; check for commands on the way.
207		 */
208		for (port = p->RIOFirstPortsBooted; port < p->RIOLastPortsBooted + PORTS_PER_RTA; port++) {
209			struct Port *PortP = p->RIOPortp[port];
210			struct tty_struct *ttyP;
211			struct PKT __iomem *PacketP;
212
213			/*
214			 ** not mapped in - most of the RIOPortp[] information
215			 ** has not been set up!
216			 ** Optimise: ports come in bundles of eight.
217			 */
218			if (!PortP->Mapped) {
219				port += 7;
220				continue;	/* with the next port */
221			}
222
223			/*
224			 ** If the host board isn't THIS host board, check the next one.
225			 ** optimise: ports come in bundles of eight.
226			 */
227			if (PortP->HostP != HostP) {
228				port += 7;
229				continue;
230			}
231
232			/*
233			 ** Let us see - is the port open? If not, then don't service it.
234			 */
235			if (!(PortP->PortState & PORT_ISOPEN)) {
236				continue;
237			}
238
239			/*
240			 ** find corresponding tty structure. The process of mapping
241			 ** the ports puts these here.
242			 */
243			ttyP = PortP->gs.port.tty;
244
245			/*
246			 ** Lock the port before we begin working on it.
247			 */
248			rio_spin_lock(&PortP->portSem);
249
250			/*
251			 ** Process received data if there is any.
252			 */
253			if (can_remove_receive(&PacketP, PortP))
254				RIOReceive(p, PortP);
255
256			/*
257			 ** If there is no data left to be read from the port, and
258			 ** it's handshake bit is set, then we must clear the handshake,
259			 ** so that that downstream RTA is re-enabled.
260			 */
261			if (!can_remove_receive(&PacketP, PortP) && (readw(&PortP->PhbP->handshake) == PHB_HANDSHAKE_SET)) {
262				/*
263				 ** MAGIC! ( Basically, handshake the RX buffer, so that
264				 ** the RTAs upstream can be re-enabled. )
265				 */
266				rio_dprintk(RIO_DEBUG_INTR, "Set RX handshake bit\n");
267				writew(PHB_HANDSHAKE_SET | PHB_HANDSHAKE_RESET, &PortP->PhbP->handshake);
268			}
269			rio_spin_unlock(&PortP->portSem);
270		}
271	}
272
273	if (readw(&HostP->ParmMapP->tx_intr)) {
274		int port;
275
276		writew(0, &HostP->ParmMapP->tx_intr);
277
278		p->RIOTxCount++;
279		TxIntr++;
280		rio_dprintk(RIO_DEBUG_INTR, "rio: TX interrupt on host %Zd\n", HostP - p->RIOHosts);
281
282		/*
283		 ** Loop through every port.
284		 ** If the port is mapped into the system ( i.e. has /dev/ttyXXXX
285		 ** associated ) then it is worth checking.
286		 */
287		for (port = p->RIOFirstPortsBooted; port < p->RIOLastPortsBooted + PORTS_PER_RTA; port++) {
288			struct Port *PortP = p->RIOPortp[port];
289			struct tty_struct *ttyP;
290			struct PKT __iomem *PacketP;
291
292			/*
293			 ** not mapped in - most of the RIOPortp[] information
294			 ** has not been set up!
295			 */
296			if (!PortP->Mapped) {
297				port += 7;
298				continue;	/* with the next port */
299			}
300
301			/*
302			 ** If the host board isn't running, then its data structures
303			 ** are no use to us - continue quietly.
304			 */
305			if (PortP->HostP != HostP) {
306				port += 7;
307				continue;	/* with the next port */
308			}
309
310			/*
311			 ** Let us see - is the port open? If not, then don't service it.
312			 */
313			if (!(PortP->PortState & PORT_ISOPEN)) {
314				continue;
315			}
316
317			rio_dprintk(RIO_DEBUG_INTR, "rio: Looking into port %d.\n", port);
318			/*
319			 ** Lock the port before we begin working on it.
320			 */
321			rio_spin_lock(&PortP->portSem);
322
323			/*
324			 ** If we can't add anything to the transmit queue, then
325			 ** we need do none of this processing.
326			 */
327			if (!can_add_transmit(&PacketP, PortP)) {
328				rio_dprintk(RIO_DEBUG_INTR, "Can't add to port, so skipping.\n");
329				rio_spin_unlock(&PortP->portSem);
330				continue;
331			}
332
333			/*
334			 ** find corresponding tty structure. The process of mapping
335			 ** the ports puts these here.
336			 */
337			ttyP = PortP->gs.port.tty;
338			/* If ttyP is NULL, the port is getting closed. Forget about it. */
339			if (!ttyP) {
340				rio_dprintk(RIO_DEBUG_INTR, "no tty, so skipping.\n");
341				rio_spin_unlock(&PortP->portSem);
342				continue;
343			}
344			/*
345			 ** If there is more room available we start up the transmit
346			 ** data process again. This can be direct I/O, if the cookmode
347			 ** is set to COOK_RAW or COOK_MEDIUM, or will be a call to the
348			 ** riotproc( T_OUTPUT ) if we are in COOK_WELL mode, to fetch
349			 ** characters via the line discipline. We must always call
350			 ** the line discipline,
351			 ** so that user input characters can be echoed correctly.
352			 **
353			 ** ++++ Update +++++
354			 ** With the advent of double buffering, we now see if
355			 ** TxBufferOut-In is non-zero. If so, then we copy a packet
356			 ** to the output place, and set it going. If this empties
357			 ** the buffer, then we must issue a wakeup( ) on OUT.
358			 ** If it frees space in the buffer then we must issue
359			 ** a wakeup( ) on IN.
360			 **
361			 ** ++++ Extra! Extra! If PortP->WflushFlag is set, then we
362			 ** have to send a WFLUSH command down the PHB, to mark the
363			 ** end point of a WFLUSH. We also need to clear out any
364			 ** data from the double buffer! ( note that WflushFlag is a
365			 ** *count* of the number of WFLUSH commands outstanding! )
366			 **
367			 ** ++++ And there's more!
368			 ** If an RTA is powered off, then on again, and rebooted,
369			 ** whilst it has ports open, then we need to re-open the ports.
370			 ** ( reasonable enough ). We can't do this when we spot the
371			 ** re-boot, in interrupt time, because the queue is probably
372			 ** full. So, when we come in here, we need to test if any
373			 ** ports are in this condition, and re-open the port before
374			 ** we try to send any more data to it. Now, the re-booted
375			 ** RTA will be discarding packets from the PHB until it
376			 ** receives this open packet, but don't worry tooo much
377			 ** about that. The one thing that is interesting is the
378			 ** combination of this effect and the WFLUSH effect!
379			 */
380			/* For now don't handle RTA reboots. -- REW.
381			   Reenabled. Otherwise RTA reboots didn't work. Duh. -- REW */
382			if (PortP->MagicFlags) {
383				if (PortP->MagicFlags & MAGIC_REBOOT) {
384					/*
385					 ** well, the RTA has been rebooted, and there is room
386					 ** on its queue to add the open packet that is required.
387					 **
388					 ** The messy part of this line is trying to decide if
389					 ** we need to call the Param function as a tty or as
390					 ** a modem.
391					 ** DONT USE CLOCAL AS A TEST FOR THIS!
392					 **
393					 ** If we can't param the port, then move on to the
394					 ** next port.
395					 */
396					PortP->InUse = NOT_INUSE;
397
398					rio_spin_unlock(&PortP->portSem);
399					if (RIOParam(PortP, RIOC_OPEN, ((PortP->Cor2Copy & (RIOC_COR2_RTSFLOW | RIOC_COR2_CTSFLOW)) == (RIOC_COR2_RTSFLOW | RIOC_COR2_CTSFLOW)) ? 1 : 0, DONT_SLEEP) == RIO_FAIL)
400						continue;	/* with next port */
401					rio_spin_lock(&PortP->portSem);
402					PortP->MagicFlags &= ~MAGIC_REBOOT;
403				}
404
405				/*
406				 ** As mentioned above, this is a tacky hack to cope
407				 ** with WFLUSH
408				 */
409				if (PortP->WflushFlag) {
410					rio_dprintk(RIO_DEBUG_INTR, "Want to WFLUSH mark this port\n");
411
412					if (PortP->InUse)
413						rio_dprintk(RIO_DEBUG_INTR, "FAILS - PORT IS IN USE\n");
414				}
415
416				while (PortP->WflushFlag && can_add_transmit(&PacketP, PortP) && (PortP->InUse == NOT_INUSE)) {
417					int p;
418					struct PktCmd __iomem *PktCmdP;
419
420					rio_dprintk(RIO_DEBUG_INTR, "Add WFLUSH marker to data queue\n");
421					/*
422					 ** make it look just like a WFLUSH command
423					 */
424					PktCmdP = (struct PktCmd __iomem *) &PacketP->data[0];
425
426					writeb(RIOC_WFLUSH, &PktCmdP->Command);
427
428					p = PortP->HostPort % (u16) PORTS_PER_RTA;
429
430					/*
431					 ** If second block of ports for 16 port RTA, add 8
432					 ** to index 8-15.
433					 */
434					if (PortP->SecondBlock)
435						p += PORTS_PER_RTA;
436
437					writeb(p, &PktCmdP->PhbNum);
438
439					/*
440					 ** to make debuggery easier
441					 */
442					writeb('W', &PacketP->data[2]);
443					writeb('F', &PacketP->data[3]);
444					writeb('L', &PacketP->data[4]);
445					writeb('U', &PacketP->data[5]);
446					writeb('S', &PacketP->data[6]);
447					writeb('H', &PacketP->data[7]);
448					writeb(' ', &PacketP->data[8]);
449					writeb('0' + PortP->WflushFlag, &PacketP->data[9]);
450					writeb(' ', &PacketP->data[10]);
451					writeb(' ', &PacketP->data[11]);
452					writeb('\0', &PacketP->data[12]);
453
454					/*
455					 ** its two bytes long!
456					 */
457					writeb(PKT_CMD_BIT | 2, &PacketP->len);
458
459					/*
460					 ** queue it!
461					 */
462					if (!(PortP->State & RIO_DELETED)) {
463						add_transmit(PortP);
464						/*
465						 ** Count chars tx'd for port statistics reporting
466						 */
467						if (PortP->statsGather)
468							PortP->txchars += 2;
469					}
470
471					if (--(PortP->WflushFlag) == 0) {
472						PortP->MagicFlags &= ~MAGIC_FLUSH;
473					}
474
475					rio_dprintk(RIO_DEBUG_INTR, "Wflush count now stands at %d\n", PortP->WflushFlag);
476				}
477				if (PortP->MagicFlags & MORE_OUTPUT_EYGOR) {
478					if (PortP->MagicFlags & MAGIC_FLUSH) {
479						PortP->MagicFlags |= MORE_OUTPUT_EYGOR;
480					} else {
481						if (!can_add_transmit(&PacketP, PortP)) {
482							rio_spin_unlock(&PortP->portSem);
483							continue;
484						}
485						rio_spin_unlock(&PortP->portSem);
486						RIOTxEnable((char *) PortP);
487						rio_spin_lock(&PortP->portSem);
488						PortP->MagicFlags &= ~MORE_OUTPUT_EYGOR;
489					}
490				}
491			}
492
493
494			/*
495			 ** If we can't add anything to the transmit queue, then
496			 ** we need do none of the remaining processing.
497			 */
498			if (!can_add_transmit(&PacketP, PortP)) {
499				rio_spin_unlock(&PortP->portSem);
500				continue;
501			}
502
503			rio_spin_unlock(&PortP->portSem);
504			RIOTxEnable((char *) PortP);
505		}
506	}
507}
508
509/*
510** Routine for handling received data for tty drivers
511*/
512static void RIOReceive(struct rio_info *p, struct Port *PortP)
513{
514	struct tty_struct *TtyP;
515	unsigned short transCount;
516	struct PKT __iomem *PacketP;
517	register unsigned int DataCnt;
518	unsigned char __iomem *ptr;
519	unsigned char *buf;
520	int copied = 0;
521
522	static int intCount, RxIntCnt;
523
524	/*
525	 ** The receive data process is to remove packets from the
526	 ** PHB until there aren't any more or the current cblock
527	 ** is full. When this occurs, there will be some left over
528	 ** data in the packet, that we must do something with.
529	 ** As we haven't unhooked the packet from the read list
530	 ** yet, we can just leave the packet there, having first
531	 ** made a note of how far we got. This means that we need
532	 ** a pointer per port saying where we start taking the
533	 ** data from - this will normally be zero, but when we
534	 ** run out of space it will be set to the offset of the
535	 ** next byte to copy from the packet data area. The packet
536	 ** length field is decremented by the number of bytes that
537	 ** we successfully removed from the packet. When this reaches
538	 ** zero, we reset the offset pointer to be zero, and free
539	 ** the packet from the front of the queue.
540	 */
541
542	intCount++;
543
544	TtyP = PortP->gs.port.tty;
545	if (!TtyP) {
546		rio_dprintk(RIO_DEBUG_INTR, "RIOReceive: tty is null. \n");
547		return;
548	}
549
550	if (PortP->State & RIO_THROTTLE_RX) {
551		rio_dprintk(RIO_DEBUG_INTR, "RIOReceive: Throttled. Can't handle more input.\n");
552		return;
553	}
554
555	if (PortP->State & RIO_DELETED) {
556		while (can_remove_receive(&PacketP, PortP)) {
557			remove_receive(PortP);
558			put_free_end(PortP->HostP, PacketP);
559		}
560	} else {
561		/*
562		 ** loop, just so long as:
563		 **   i ) there's some data ( i.e. can_remove_receive )
564		 **  ii ) we haven't been blocked
565		 ** iii ) there's somewhere to put the data
566		 **  iv ) we haven't outstayed our welcome
567		 */
568		transCount = 1;
569		while (can_remove_receive(&PacketP, PortP)
570		       && transCount) {
571			RxIntCnt++;
572
573			/*
574			 ** check that it is not a command!
575			 */
576			if (readb(&PacketP->len) & PKT_CMD_BIT) {
577				rio_dprintk(RIO_DEBUG_INTR, "RIO: unexpected command packet received on PHB\n");
578				/*      rio_dprint(RIO_DEBUG_INTR, (" sysport   = %d\n", p->RIOPortp->PortNum)); */
579				rio_dprintk(RIO_DEBUG_INTR, " dest_unit = %d\n", readb(&PacketP->dest_unit));
580				rio_dprintk(RIO_DEBUG_INTR, " dest_port = %d\n", readb(&PacketP->dest_port));
581				rio_dprintk(RIO_DEBUG_INTR, " src_unit  = %d\n", readb(&PacketP->src_unit));
582				rio_dprintk(RIO_DEBUG_INTR, " src_port  = %d\n", readb(&PacketP->src_port));
583				rio_dprintk(RIO_DEBUG_INTR, " len	   = %d\n", readb(&PacketP->len));
584				rio_dprintk(RIO_DEBUG_INTR, " control   = %d\n", readb(&PacketP->control));
585				rio_dprintk(RIO_DEBUG_INTR, " csum	   = %d\n", readw(&PacketP->csum));
586				rio_dprintk(RIO_DEBUG_INTR, "	 data bytes: ");
587				for (DataCnt = 0; DataCnt < PKT_MAX_DATA_LEN; DataCnt++)
588					rio_dprintk(RIO_DEBUG_INTR, "%d\n", readb(&PacketP->data[DataCnt]));
589				remove_receive(PortP);
590				put_free_end(PortP->HostP, PacketP);
591				continue;	/* with next packet */
592			}
593
594			/*
595			 ** How many characters can we move 'upstream' ?
596			 **
597			 ** Determine the minimum of the amount of data
598			 ** available and the amount of space in which to
599			 ** put it.
600			 **
601			 ** 1.        Get the packet length by masking 'len'
602			 **   for only the length bits.
603			 ** 2.        Available space is [buffer size] - [space used]
604			 **
605			 ** Transfer count is the minimum of packet length
606			 ** and available space.
607			 */
608
609			transCount = tty_buffer_request_room(TtyP, readb(&PacketP->len) & PKT_LEN_MASK);
610			rio_dprintk(RIO_DEBUG_REC, "port %d: Copy %d bytes\n", PortP->PortNum, transCount);
611			/*
612			 ** To use the following 'kkprintfs' for debugging - change the '#undef'
613			 ** to '#define', (this is the only place ___DEBUG_IT___ occurs in the
614			 ** driver).
615			 */
616			ptr = (unsigned char __iomem *) PacketP->data + PortP->RxDataStart;
617
618			tty_prepare_flip_string(TtyP, &buf, transCount);
619			rio_memcpy_fromio(buf, ptr, transCount);
620			PortP->RxDataStart += transCount;
621			writeb(readb(&PacketP->len)-transCount, &PacketP->len);
622			copied += transCount;
623
624
625
626			if (readb(&PacketP->len) == 0) {
627				/*
628				 ** If we have emptied the packet, then we can
629				 ** free it, and reset the start pointer for
630				 ** the next packet.
631				 */
632				remove_receive(PortP);
633				put_free_end(PortP->HostP, PacketP);
634				PortP->RxDataStart = 0;
635			}
636		}
637	}
638	if (copied) {
639		rio_dprintk(RIO_DEBUG_REC, "port %d: pushing tty flip buffer: %d total bytes copied.\n", PortP->PortNum, copied);
640		tty_flip_buffer_push(TtyP);
641	}
642
643	return;
644}
645