aboutsummaryrefslogtreecommitdiff
path: root/drivers/char/ser_a2232.c
blob: 33872a219df6b57355f5dd1eb5e988f9e8bb89d3 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
/* drivers/char/ser_a2232.c */

/* $Id: ser_a2232.c,v 0.4 2000/01/25 12:00:00 ehaase Exp $ */

/* Linux serial driver for the Amiga A2232 board */

/* This driver is MAINTAINED. Before applying any changes, please contact
 * the author.
 */

/* Copyright (c) 2000-2001 Enver Haase    <ehaase@inf.fu-berlin.de>
 *                   alias The A2232 driver project <A2232@gmx.net>
 * All rights reserved.
 *
 *   This program is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation; either version 2 of the License, or
 *   (at your option) any later version.
 *
 *   This program is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this program; if not, write to the Free Software
 *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 */
/***************************** Documentation ************************/
/*
 * This driver is in EXPERIMENTAL state. That means I could not find
 * someone with five A2232 boards with 35 ports running at 19200 bps
 * at the same time and test the machine's behaviour.
 * However, I know that you can performance-tweak this driver (see
 * the source code).
 * One thing to consider is the time this driver consumes during the
 * Amiga's vertical blank interrupt. Everything that is to be done
 * _IS DONE_ when entering the vertical blank interrupt handler of
 * this driver.
 * However, it would be more sane to only do the job for only ONE card
 * instead of ALL cards at a time; or, more generally, to handle only
 * SOME ports instead of ALL ports at a time.
 * However, as long as no-one runs into problems I guess I shouldn't
 * change the driver as it runs fine for me :) .
 *
 * Version history of this file:
 * 0.4	Resolved licensing issues.
 * 0.3	Inclusion in the Linux/m68k tree, small fixes.
 * 0.2	Added documentation, minor typo fixes.
 * 0.1	Initial release.
 *
 * TO DO:
 * -	Handle incoming BREAK events. I guess "Stevens: Advanced
 *	Programming in the UNIX(R) Environment" is a good reference
 *	on what is to be done.
 * -	When installing as a module, don't simply 'printk' text, but
 *	send it to the TTY used by the user.
 *
 * THANKS TO:
 * -	Jukka Marin (65EC02 code).
 * -	The other NetBSD developers on whose A2232 driver I had a
 *	pretty close look. However, I didn't copy any code so it
 *	is okay to put my code under the GPL and include it into
 *	Linux.
 */
/***************************** End of Documentation *****************/

/***************************** Defines ******************************/
/*
 * Enables experimental 115200 (normal) 230400 (turbo) baud rate.
 * The A2232 specification states it can only operate at speeds up to
 * 19200 bits per second, and I was not able to send a file via
 * "sz"/"rz" and a null-modem cable from one A2232 port to another
 * at 115200 bits per second.
 * However, this might work for you.
 */
#undef A2232_SPEEDHACK
/*
 * Default is not to use RTS/CTS so you could be talked to death.
 */
#define A2232_SUPPRESS_RTSCTS_WARNING
/************************* End of Defines ***************************/

/***************************** Includes *****************************/
#include <linux/module.h>

#include <linux/types.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/tty.h>

#include <asm/setup.h>
#include <asm/amigaints.h>
#include <asm/amigahw.h>
#include <linux/zorro.h>
#include <asm/irq.h>
#include <linux/mutex.h>

#include <linux/delay.h>

#include <linux/serial.h>
#include <linux/generic_serial.h>
#include <linux/tty_flip.h>

#include "ser_a2232.h"
#include "ser_a2232fw.h"
/************************* End of Includes **************************/

/***************************** Prototypes ***************************/
/* The interrupt service routine */
static irqreturn_t a2232_vbl_inter(int irq, void *data);
/* Initialize the port structures */
static void a2232_init_portstructs(void);
/* Initialize and register TTY drivers. */
/* returns 0 IFF successful */
static int a2232_init_drivers(void); 

/* BEGIN GENERIC_SERIAL PROTOTYPES */
static void a2232_disable_tx_interrupts(void *ptr);
static void a2232_enable_tx_interrupts(void *ptr);
static void a2232_disable_rx_interrupts(void *ptr);
static void a2232_enable_rx_interrupts(void *ptr);
static int  a2232_carrier_raised(struct tty_port *port);
static void a2232_shutdown_port(void *ptr);
static int  a2232_set_real_termios(void *ptr);
static int  a2232_chars_in_buffer(void *ptr);
static void a2232_close(void *ptr);
static void a2232_hungup(void *ptr);
/* static void a2232_getserial (void *ptr, struct serial_struct *sp); */
/* END GENERIC_SERIAL PROTOTYPES */

/* Functions that the TTY driver struct expects */
static int  a2232_ioctl(struct tty_struct *tty, struct file *file,
										unsigned int cmd, unsigned long arg);
static void a2232_throttle(struct tty_struct *tty);
static void a2232_unthrottle(struct tty_struct *tty);
static int  a2232_open(struct tty_struct * tty, struct file * filp);
/************************* End of Prototypes ************************/

/***************************** Global variables *********************/
/*---------------------------------------------------------------------------
 * Interface from generic_serial.c back here
 *--------------------------------------------------------------------------*/
static struct real_driver a2232_real_driver = {
        a2232_disable_tx_interrupts,
        a2232_enable_tx_interrupts,
        a2232_disable_rx_interrupts,
        a2232_enable_rx_interrupts,
        a2232_shutdown_port,
        a2232_set_real_termios,
        a2232_chars_in_buffer,
        a2232_close,
        a2232_hungup,
	NULL	/* a2232_getserial */
};

static void *a2232_driver_ID = &a2232_driver_ID; // Some memory address WE own.

/* Ports structs */
static struct a2232_port a2232_ports[MAX_A2232_BOARDS*NUMLINES];

/* TTY driver structs */
static struct tty_driver *a2232_driver;

/* nr of cards completely (all ports) and correctly configured */
static int nr_a2232; 

/* zorro_dev structs for the A2232's */
static struct zorro_dev *zd_a2232[MAX_A2232_BOARDS]; 
/***************************** End of Global variables **************/

/* Helper functions */

static inline volatile struct a2232memory *a2232mem(unsigned int board)
{
	return (volatile struct a2232memory *)ZTWO_VADDR(zd_a2232[board]->resource.start);
}

static inline volatile struct a2232status *a2232stat(unsigned int board,
						     unsigned int portonboard)
{
	volatile struct a2232memory *mem = a2232mem(board);
	return &(mem->Status[portonboard]);
}

static inline void a2232_receive_char(struct a2232_port *port, int ch, int err)
{
/* 	Mostly stolen from other drivers.
	Maybe one could implement a more efficient version by not only
	transferring one character at a time.
*/
	struct tty_struct *tty = port->gs.port.tty;

#if 0
	switch(err) {
	case TTY_BREAK:
		break;
	case TTY_PARITY:
		break;
	case TTY_OVERRUN:
		break;
	case TTY_FRAME:
		break;
	}
#endif

	tty_insert_flip_char(tty, ch, err);
	tty_flip_buffer_push(tty);
}

/***************************** Functions ****************************/
/*** BEGIN OF REAL_DRIVER FUNCTIONS ***/

static void a2232_disable_tx_interrupts(void *ptr)
{
	struct a2232_port *port;
	volatile struct a2232status *stat;
	unsigned long flags;
  
	port = ptr;
	stat = a2232stat(port->which_a2232, port->which_port_on_a2232);
	stat->OutDisable = -1;

	/* Does this here really have to be? */
	local_irq_save(flags);
	port->gs.port.flags &= ~GS_TX_INTEN;
	local_irq_restore(flags);
}

static void a2232_enable_tx_interrupts(void *ptr)
{
	struct a2232_port *port;
	volatile struct a2232status *stat;
	unsigned long flags;

	port = ptr;
	stat = a2232stat(port->which_a2232, port->which_port_on_a2232);
	stat->OutDisable = 0;

	/* Does this here really have to be? */
	local_irq_save(flags);
	port->gs.port.flags |= GS_TX_INTEN;
	local_irq_restore(flags);
}

static void a2232_disable_rx_interrupts(void *ptr)
{
	struct a2232_port *port;
	port = ptr;
	port->disable_rx = -1;
}

static void a2232_enable_rx_interrupts(void *ptr)
{
	struct a2232_port *port;
	port = ptr;
	port->disable_rx = 0;
}

static int  a2232_carrier_raised(struct tty_port *port)
{
	struct a2232_port *ap = container_of(port, struct a2232_port, gs.port);
	return ap->cd_status;
}

static void a2232_shutdown_port(void *ptr)
{
	struct a2232_port *port;
	volatile struct a2232status *stat;
	unsigned long flags;

	port = ptr;
	stat = a2232stat(port->which_a2232, port->which_port_on_a2232);

	local_irq_save(flags);

	port->gs.port.flags &= ~GS_ACTIVE;
	
	if (port->gs.port.tty && port->gs.port.tty->termios->c_cflag & HUPCL) {
		/* Set DTR and RTS to Low, flush output.
		   The NetBSD driver "msc.c" does it this way. */
		stat->Command = (	(stat->Command & ~A2232CMD_CMask) | 
					A2232CMD_Close );
		stat->OutFlush = -1;
		stat->Setup = -1;
	}

	local_irq_restore(flags);
	
	/* After analyzing control flow, I think a2232_shutdown_port
		is actually the last call from the system when at application
		level someone issues a "echo Hello >>/dev/ttyY0".
		Therefore I think the MOD_DEC_USE_COUNT should be here and
		not in "a2232_close()". See the comment in "sx.c", too.
		If you run into problems, compile this driver into the
		kernel instead of compiling it as a module. */
}

static int  a2232_set_real_termios(void *ptr)
{
	unsigned int cflag, baud, chsize, stopb, parity, softflow;
	int rate;
	int a2232_param, a2232_cmd;
	unsigned long flags;
	unsigned int i;
	struct a2232_port *port = ptr;
	volatile struct a2232status *status;
	volatile struct a2232memory *mem;

	if (!port->gs.port.tty || !port->gs.port.tty->termios) return 0;

	status = a2232stat(port->which_a2232, port->which_port_on_a2232);
	mem = a2232mem(port->which_a2232);
	
	a2232_param = a2232_cmd = 0;

	// get baud rate
	baud = port->gs.baud;
	if (baud == 0) {
		/* speed == 0 -> drop DTR, do nothing else */
		local_irq_save(flags);
		// Clear DTR (and RTS... mhhh).
		status->Command = (	(status->Command & ~A2232CMD_CMask) |
					A2232CMD_Close );
		status->OutFlush = -1;
		status->Setup = -1;
		
		local_irq_restore(flags);
		return 0;
	}
	
	rate = A2232_BAUD_TABLE_NOAVAIL;
	for (i=0; i < A2232_BAUD_TABLE_NUM_RATES * 3; i += 3){
		if (a2232_baud_table[i] == baud){
			if (mem->Common.Crystal == A2232_TURBO) rate = a2232_baud_table[i+2];
			else                                    rate = a2232_baud_table[i+1];
		}
	}
	if (rate == A2232_BAUD_TABLE_NOAVAIL){
		printk("a2232: Board %d Port %d unsupported baud rate: %d baud. Using another.\n",port->which_a2232,port->which_port_on_a2232,baud);
		// This is useful for both (turbo or normal) Crystal versions.
		rate = A2232PARAM_B9600;
	}
	a2232_param |= rate;

	cflag  = port->gs.port.tty->termios->c_cflag;

	// get character size
	chsize = cflag & CSIZE;
	switch (chsize){
		case CS8: 	a2232_param |= A2232PARAM_8Bit; break;
		case CS7: 	a2232_param |= A2232PARAM_7Bit; break;
		case CS6: 	a2232_param |= A2232PARAM_6Bit; break;
		case CS5: 	a2232_param |= A2232PARAM_5Bit; break;
		default:	printk("a2232: Board %d Port %d unsupported character size: %d. Using 8 data bits.\n",
					port->which_a2232,port->which_port_on_a2232,chsize);
				a2232_param |= A2232PARAM_8Bit; break;
	}

	// get number of stop bits
	stopb  = cflag & CSTOPB;
	if (stopb){ // two stop bits instead of one
		printk("a2232: Board %d Port %d 2 stop bits unsupported. Using 1 stop bit.\n",
			port->which_a2232,port->which_port_on_a2232);
	}

	// Warn if RTS/CTS not wanted
	if (!(cflag & CRTSCTS)){
#ifndef A2232_SUPPRESS_RTSCTS_WARNING
		printk("a2232: Board %d Port %d cannot switch off firmware-implemented RTS/CTS hardware flow control.\n",
			port->which_a2232,port->which_port_on_a2232);
#endif
	}

	/*	I think this is correct.
		However, IXOFF means _input_ flow control and I wonder
		if one should care about IXON _output_ flow control,
		too. If this makes problems, one should turn the A2232
		firmware XON/XOFF "SoftFlow" flow control off and use
		the conventional way of inserting START/STOP characters
		by hand in throttle()/unthrottle().
	*/
	softflow = !!( port->gs.port.tty->termios->c_iflag & IXOFF );

	// get Parity (Enabled/Disabled? If Enabled, Odd or Even?)
	parity = cflag & (PARENB | PARODD);
	if (parity & PARENB){
		if (parity & PARODD){
			a2232_cmd |= A2232CMD_OddParity;
		}
		else{
			a2232_cmd |= A2232CMD_EvenParity;
		}
	}
	else a2232_cmd |= A2232CMD_NoParity;


	/*	Hmm. Maybe an own a2232_port structure
		member would be cleaner?	*/
	if (cflag & CLOCAL)
		port->gs.port.flags &= ~ASYNC_CHECK_CD;
	else
		port->gs.port.flags |= ASYNC_CHECK_CD;


	/* Now we have all parameters and can go to set them: */
	local_irq_save(flags);

	status->Param = a2232_param | A2232PARAM_RcvBaud;
	status->Command = a2232_cmd | A2232CMD_Open |  A2232CMD_Enable;
	status->SoftFlow = softflow;
	status->OutDisable = 0;
	status->Setup = -1;

	local_irq_restore(flags);
	return 0;
}

static int  a2232_chars_in_buffer(void *ptr)
{
	struct a2232_port *port;
	volatile struct a2232status *status; 
	unsigned char ret; /* we need modulo-256 arithmetics */
	port = ptr;
	status = a2232stat(port->which_a2232, port->which_port_on_a2232);
#if A2232_IOBUFLEN != 256
#error "Re-Implement a2232_chars_in_buffer()!"
#endif
	ret = (status->OutHead - status->OutTail);
	return ret;
}

static void a2232_close(void *ptr)
{
	a2232_disable_tx_interrupts(ptr);
	a2232_disable_rx_interrupts(ptr);
	/* see the comment in a2232_shutdown_port above. */
}

static void a2232_hungup(void *ptr)
{
	a2232_close(ptr);
}
/*** END   OF REAL_DRIVER FUNCTIONS ***/

/*** BEGIN  FUNCTIONS EXPECTED BY TTY DRIVER STRUCTS ***/
static int a2232_ioctl(	struct tty_struct *tty, struct file *file,
			unsigned int cmd, unsigned long arg)
{
	return -ENOIOCTLCMD;
}

static void a2232_throttle(struct tty_struct *tty)
{
/* Throttle: System cannot take another chars: Drop RTS or
             send the STOP char or whatever.
   The A2232 firmware does RTS/CTS anyway, and XON/XOFF
   if switched on. So the only thing we can do at this
   layer here is not taking any characters out of the
   A2232 buffer any more. */
	struct a2232_port *port = tty->driver_data;
	port->throttle_input = -1;
}

static void a2232_unthrottle(struct tty_struct *tty)
{
/* Unthrottle: dual to "throttle()" above. */
	struct a2232_port *port = tty->driver_data;
	port->throttle_input = 0;
}

static int  a2232_open(struct tty_struct * tty, struct file * filp)
{
/* More or less stolen from other drivers. */
	int line;
	int retval;
	struct a2232_port *port;

	line = tty->index;
	port = &a2232_ports[line];
	
	tty->driver_data = port;
	port->gs.port.tty = tty;
	port->gs.port.count++;
	retval = gs_init_port(&port->gs);
	if (retval) {
		port->gs.port.count--;
		return retval;
	}
	port->gs.port.flags |= GS_ACTIVE;
	retval = gs_block_til_ready(port, filp);

	if (retval) {
		port->gs.port.count--;
		return retval;
	}

	a2232_enable_rx_interrupts(port);
	
	return 0;
}
/*** END OF FUNCTIONS EXPECTED BY TTY DRIVER STRUCTS ***/

static irqreturn_t a2232_vbl_inter(int irq, void *data)
{
#if A2232_IOBUFLEN != 256
#error "Re-Implement a2232_vbl_inter()!"
#endif

struct a2232_port *port;
volatile struct a2232memory *mem;
volatile struct a2232status *status;
unsigned char newhead;
unsigned char bufpos; /* Must be unsigned char. We need the modulo-256 arithmetics */
unsigned char ncd, ocd, ccd; /* names consistent with the NetBSD driver */
volatile u_char *ibuf, *cbuf, *obuf;
int ch, err, n, p;
	for (n = 0; n < nr_a2232; n++){		/* for every completely initialized A2232 board */
		mem = a2232mem(n);
		for (p = 0; p < NUMLINES; p++){	/* for every port on this board */
			err = 0;
			port = &a2232_ports[n*NUMLINES+p];
			if ( port->gs.port.flags & GS_ACTIVE ){ /* if the port is used */

				status = a2232stat(n,p);

				if (!port->disable_rx && !port->throttle_input){ /* If input is not disabled */
					newhead = status->InHead;               /* 65EC02 write pointer */
					bufpos = status->InTail;

					/* check for input for this port */
					if (newhead != bufpos) {
						/* buffer for input chars/events */
						ibuf = mem->InBuf[p];
 
						/* data types of bytes in ibuf */
						cbuf = mem->InCtl[p];
 
						/* do for all chars */
						while (bufpos != newhead) {
							/* which type of input data? */
							switch (cbuf[bufpos]) {
								/* switch on input event (CD, BREAK, etc.) */
							case A2232INCTL_EVENT:
								switch (ibuf[bufpos++]) {
								case A2232EVENT_Break:
									/* TODO: Handle BREAK signal */
									break;
									/*	A2232EVENT_CarrierOn and A2232EVENT_CarrierOff are
										handled in a separate queue and should not occur here. */
								case A2232EVENT_Sync:
									printk("A2232: 65EC02 software sent SYNC event, don't know what to do. Ignoring.");
									break;
								default:
									printk("A2232: 65EC02 software broken, unknown event type %d occurred.\n",ibuf[bufpos-1]);
								} /* event type switch */
								break;
 							case A2232INCTL_CHAR:
								/* Receive incoming char */
								a2232_receive_char(port, ibuf[bufpos], err);
								bufpos++;
								break;
 							default:
								printk("A2232: 65EC02 software broken, unknown data type %d occurred.\n",cbuf[bufpos]);
								bufpos++;
							} /* switch on input data type */
						} /* while there's something in the buffer */

						status->InTail = bufpos;            /* tell 65EC02 what we've read */
						
					} /* if there was something in the buffer */                          
				} /* If input is not disabled */

				/* Now check if there's something to output */
				obuf = mem->OutBuf[p];
				bufpos = status->OutHead;
				while ( (port->gs.xmit_cnt > 0)		&&
					(!port->gs.port.tty->stopped)	&&
					(!port->gs.port.tty->hw_stopped) ){	/* While there are chars to transmit */
					if (((bufpos+1) & A2232_IOBUFLENMASK) != status->OutTail) { /* If the A2232 buffer is not full */
						ch = port->gs.xmit_buf[port->gs.xmit_tail];					/* get the next char to transmit */
						port->gs.xmit_tail = (port->gs.xmit_tail+1) & (SERIAL_XMIT_SIZE-1); /* modulo-addition for the gs.xmit_buf ring-buffer */
						obuf[bufpos++] = ch;																/* put it into the A2232 buffer */
						port->gs.xmit_cnt--;
					}
					else{																									/* If A2232 the buffer is full */
						break;																							/* simply stop filling it. */
					}													
				}					
				status->OutHead = bufpos;
					
				/* WakeUp if output buffer runs low */
				if ((port->gs.xmit_cnt <= port->gs.wakeup_chars) && port->gs.port.tty) {
					tty_wakeup(port->gs.port.tty);
				}
			} // if the port is used
		} // for every port on the board
			
		/* Now check the CD message queue */
		newhead = mem->Common.CDHead;
		bufpos = mem->Common.CDTail;
		if (newhead != bufpos){				/* There are CD events in queue */
			ocd = mem->Common.CDStatus; 		/* get old status bits */
			while (newhead != bufpos){		/* read all events */
				ncd = mem->CDBuf[bufpos++]; 	/* get one event */
				ccd = ncd ^ ocd; 		/* mask of changed lines */
				ocd = ncd; 			/* save new status bits */
				for(p=0; p < NUMLINES; p++){	/* for all ports */
					if (ccd & 1){		/* this one changed */

						struct a2232_port *port = &a2232_ports[n*7+p];
						port->cd_status = !(ncd & 1); /* ncd&1 <=> CD is now off */

						if (!(port->gs.port.flags & ASYNC_CHECK_CD))
							;	/* Don't report DCD changes */
						else if (port->cd_status) { // if DCD on: DCD went UP!
							
							/* Are we blocking in open?*/
							wake_up_interruptible(&port->gs.port.open_wait);
						}
						else { // if DCD off: DCD went DOWN!
							if (port->gs.port.tty)
								tty_hangup (port->gs.port.tty);
						}
						
					} // if CD changed for this port
					ccd >>= 1;
					ncd >>= 1;									/* Shift bits for next line */
				} // for every port
			} // while CD events in queue
			mem->Common.CDStatus = ocd; /* save new status */
			mem->Common.CDTail = bufpos; /* remove events */
		} // if events in CD queue
		
	} // for every completely initialized A2232 board
	return IRQ_HANDLED;
}

static const struct tty_port_operations a2232_port_ops = {
	.carrier_raised = a2232_carrier_raised,
};

static void a2232_init_portstructs(void)
{
	struct a2232_port *port;
	int i;

	for (i = 0; i < MAX_A2232_BOARDS*NUMLINES; i++) {
		port = a2232_ports + i;
		tty_port_init(&port->gs.port);
		port->gs.port.ops = &a2232_port_ops;
		port->which_a2232 = i/NUMLINES;
		port->which_port_on_a2232 = i%NUMLINES;
		port->disable_rx = port->throttle_input = port->cd_status = 0;
		port->gs.magic = A2232_MAGIC;
		port->gs.close_delay = HZ/2;
		port->gs.closing_wait = 30 * HZ;
		port->gs.rd = &a2232_real_driver;
	}
}

static const struct tty_operations a2232_ops = {
	.open = a2232_open,
	.close = gs_close,
	.write = gs_write,
	.put_char = gs_put_char,
	.flush_chars = gs_flush_chars,
	.write_room = gs_write_room,
	.chars_in_buffer = gs_chars_in_buffer,
	.flush_buffer = gs_flush_buffer,
	.ioctl = a2232_ioctl,
	.throttle = a2232_throttle,
	.unthrottle = a2232_unthrottle,
	.set_termios = gs_set_termios,
	.stop = gs_stop,
	.start = gs_start,
	.hangup = gs_hangup,
};

static int a2232_init_drivers(void)
{
	int error;

	a2232_driver = alloc_tty_driver(NUMLINES * nr_a2232);
	if (!a2232_driver)
		return -ENOMEM;
	a2232_driver->owner = THIS_MODULE;
	a2232_driver->driver_name = "commodore_a2232";
	a2232_driver->name = "ttyY";
	a2232_driver->major = A2232_NORMAL_MAJOR;
	a2232_driver->type = TTY_DRIVER_TYPE_SERIAL;
	a2232_driver->subtype = SERIAL_TYPE_NORMAL;
	a2232_driver->init_termios = tty_std_termios;
	a2232_driver->init_termios.c_cflag =
		B9600 | CS8 | CREAD | HUPCL | CLOCAL;
	a2232_driver->init_termios.c_ispeed = 9600;
	a2232_driver->init_termios.c_ospeed = 9600;
	a2232_driver->flags = TTY_DRIVER_REAL_RAW;
	tty_set_operations(a2232_driver, &a2232_ops);
	if ((error = tty_register_driver(a2232_driver))) {
		printk(KERN_ERR "A2232: Couldn't register A2232 driver, error = %d\n",
		       error);
		put_tty_driver(a2232_driver);
		return 1;
	}
	return 0;
}

static int __init a2232board_init(void)
{
	struct zorro_dev *z;

	unsigned int boardaddr;
	int bcount;
	short start;
	u_char *from;
	volatile u_char *to;
	volatile struct a2232memory *mem;

#ifdef CONFIG_SMP
	return -ENODEV;	/* This driver is not SMP aware. Is there an SMP ZorroII-bus-machine? */
#endif

	if (!MACH_IS_AMIGA){
		return -ENODEV;
	}

	printk("Commodore A2232 driver initializing.\n"); /* Say that we're alive. */

	z = NULL;
	nr_a2232 = 0;
	while ( (z = zorro_find_device(ZORRO_WILDCARD, z)) ){
		if (	(z->id != ZORRO_PROD_CBM_A2232_PROTOTYPE) && 
			(z->id != ZORRO_PROD_CBM_A2232)	){
			continue;	// The board found was no A2232
		}
		if (!zorro_request_device(z,"A2232 driver"))
			continue;

		printk("Commodore A2232 found (#%d).\n",nr_a2232);

		zd_a2232[nr_a2232] = z;

		boardaddr = ZTWO_VADDR( z->resource.start );
		printk("Board is located at address 0x%x, size is 0x%x.\n", boardaddr, (unsigned int) ((z->resource.end+1) - (z->resource.start)));

		mem = (volatile struct a2232memory *) boardaddr;

		(void) mem->Enable6502Reset;   /* copy the code across to the board */
		to = (u_char *)mem;  from = a2232_65EC02code; bcount = sizeof(a2232_65EC02code) - 2;
		start = *(short *)from;
		from += sizeof(start);
		to += start;
		while(bcount--) *to++ = *from++;
		printk("65EC02 software uploaded to the A2232 memory.\n");
  
		mem->Common.Crystal = A2232_UNKNOWN;  /* use automatic speed check */
  
		/* start 6502 running */
		(void) mem->ResetBoard;
		printk("A2232's 65EC02 CPU up and running.\n");
  
		/* wait until speed detector has finished */
		for (bcount = 0; bcount < 2000; bcount++) {
			udelay(1000);
			if (mem->Common.Crystal)
				break;
		}
		printk((mem->Common.Crystal?"A2232 oscillator crystal detected by 65EC02 software: ":"65EC02 software could not determine A2232 oscillator crystal: "));
		switch (mem->Common.Crystal){
		case A2232_UNKNOWN:
			printk("Unknown crystal.\n");
			break;
 		case A2232_NORMAL:
			printk ("Normal crystal.\n");
			break;
		case A2232_TURBO:
			printk ("Turbo crystal.\n");
			break;
		default:
			printk ("0x%x. Huh?\n",mem->Common.Crystal);
		}

		nr_a2232++;

	}	

	printk("Total: %d A2232 boards initialized.\n", nr_a2232); /* Some status report if no card was found */

	a2232_init_portstructs();

	/*
		a2232_init_drivers also registers the drivers. Must be here because all boards
		have to be detected first.
	*/
	if (a2232_init_drivers()) return -ENODEV; // maybe we should use a different -Exxx?

	request_irq(IRQ_AMIGA_VERTB, a2232_vbl_inter, 0, "A2232 serial VBL", a2232_driver_ID);
	return 0;
}

static void __exit a2232board_exit(void)
{
	int i;

	for (i = 0; i < nr_a2232; i++) {
		zorro_release_device(zd_a2232[i]);
	}

	tty_unregister_driver(a2232_driver);
	put_tty_driver(a2232_driver);
	free_irq(IRQ_AMIGA_VERTB, a2232_driver_ID);
}

module_init(a2232board_init);
module_exit(a2232board_exit);

MODULE_AUTHOR("Enver Haase");
MODULE_DESCRIPTION("Amiga A2232 multi-serial board driver");
MODULE_LICENSE("GPL");