1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*****************************************************************************/
3 
4 /*
5  *	baycom_ser_fdx.c  -- baycom ser12 fullduplex radio modem driver.
6  *
7  *	Copyright (C) 1996-2000  Thomas Sailer (sailer@ife.ee.ethz.ch)
8  *
9  *  Please note that the GPL allows you to use the driver, NOT the radio.
10  *  In order to use the radio, you need a license from the communications
11  *  authority of your country.
12  *
13  *  Supported modems
14  *
15  *  ser12:  This is a very simple 1200 baud AFSK modem. The modem consists only
16  *          of a modulator/demodulator chip, usually a TI TCM3105. The computer
17  *          is responsible for regenerating the receiver bit clock, as well as
18  *          for handling the HDLC protocol. The modem connects to a serial port,
19  *          hence the name. Since the serial port is not used as an async serial
20  *          port, the kernel driver for serial ports cannot be used, and this
21  *          driver only supports standard serial hardware (8250, 16450, 16550A)
22  *
23  *          This modem usually draws its supply current out of the otherwise unused
24  *          TXD pin of the serial port. Thus a contiguous stream of 0x00-bytes
25  *          is transmitted to achieve a positive supply voltage.
26  *
27  *  hsk:    This is a 4800 baud FSK modem, designed for TNC use. It works fine
28  *          in 'baycom-mode' :-)  In contrast to the TCM3105 modem, power is
29  *          externally supplied. So there's no need to provide the 0x00-byte-stream
30  *          when receiving or idle, which drastically reduces interrupt load.
31  *
32  *  Command line options (insmod command line)
33  *
34  *  mode     ser#    hardware DCD
35  *           ser#*   software DCD
36  *           ser#+   hardware DCD, inverted signal at DCD pin
37  *           '#' denotes the baud rate / 100, eg. ser12* is '1200 baud, soft DCD'
38  *  iobase   base address of the port; common values are 0x3f8, 0x2f8, 0x3e8, 0x2e8
39  *  baud     baud rate (between 300 and 4800)
40  *  irq      interrupt line of the port; common values are 4,3
41  *
42  *  History:
43  *   0.1  26.06.1996  Adapted from baycom.c and made network driver interface
44  *        18.10.1996  Changed to new user space access routines (copy_{to,from}_user)
45  *   0.3  26.04.1997  init code/data tagged
46  *   0.4  08.07.1997  alternative ser12 decoding algorithm (uses delta CTS ints)
47  *   0.5  11.11.1997  ser12/par96 split into separate files
48  *   0.6  24.01.1998  Thorsten Kranzkowski, dl8bcu and Thomas Sailer:
49  *                    reduced interrupt load in transmit case
50  *                    reworked receiver
51  *   0.7  03.08.1999  adapt to Linus' new __setup/__initcall
52  *   0.8  10.08.1999  use module_init/module_exit
53  *   0.9  12.02.2000  adapted to softnet driver interface
54  *   0.10 03.07.2000  fix interface name handling
55  */
56 
57 /*****************************************************************************/
58 
59 #include <linux/capability.h>
60 #include <linux/module.h>
61 #include <linux/ioport.h>
62 #include <linux/string.h>
63 #include <linux/init.h>
64 #include <linux/interrupt.h>
65 #include <linux/hdlcdrv.h>
66 #include <linux/baycom.h>
67 #include <linux/jiffies.h>
68 #include <linux/time64.h>
69 
70 #include <linux/uaccess.h>
71 #include <asm/io.h>
72 #include <asm/irq.h>
73 
74 /* --------------------------------------------------------------------- */
75 
76 #define BAYCOM_DEBUG
77 
78 /* --------------------------------------------------------------------- */
79 
80 static const char bc_drvname[] = "baycom_ser_fdx";
81 static const char bc_drvinfo[] = KERN_INFO "baycom_ser_fdx: (C) 1996-2000 Thomas Sailer, HB9JNX/AE4WA\n"
82 "baycom_ser_fdx: version 0.10\n";
83 
84 /* --------------------------------------------------------------------- */
85 
86 #define NR_PORTS 4
87 
88 static struct net_device *baycom_device[NR_PORTS];
89 
90 /* --------------------------------------------------------------------- */
91 
92 #define RBR(iobase) (iobase+0)
93 #define THR(iobase) (iobase+0)
94 #define IER(iobase) (iobase+1)
95 #define IIR(iobase) (iobase+2)
96 #define FCR(iobase) (iobase+2)
97 #define LCR(iobase) (iobase+3)
98 #define MCR(iobase) (iobase+4)
99 #define LSR(iobase) (iobase+5)
100 #define MSR(iobase) (iobase+6)
101 #define SCR(iobase) (iobase+7)
102 #define DLL(iobase) (iobase+0)
103 #define DLM(iobase) (iobase+1)
104 
105 #define SER12_EXTENT 8
106 
107 /* ---------------------------------------------------------------------- */
108 /*
109  * Information that need to be kept for each board.
110  */
111 
112 struct baycom_state {
113 	struct hdlcdrv_state hdrv;
114 
115 	unsigned int baud, baud_us, baud_arbdiv, baud_uartdiv, baud_dcdtimeout;
116 	int opt_dcd;
117 
118 	struct modem_state {
119 		unsigned char flags;
120 		unsigned char ptt;
121 		unsigned int shreg;
122 		struct modem_state_ser12 {
123 			unsigned char tx_bit;
124 			unsigned char last_rxbit;
125 			int dcd_sum0, dcd_sum1, dcd_sum2;
126 			int dcd_time;
127 			unsigned int pll_time;
128 			unsigned int txshreg;
129 		} ser12;
130 	} modem;
131 
132 #ifdef BAYCOM_DEBUG
133 	struct debug_vals {
134 		unsigned long last_jiffies;
135 		unsigned cur_intcnt;
136 		unsigned last_intcnt;
137 		int cur_pllcorr;
138 		int last_pllcorr;
139 	} debug_vals;
140 #endif /* BAYCOM_DEBUG */
141 };
142 
143 /* --------------------------------------------------------------------- */
144 
145 static inline void baycom_int_freq(struct baycom_state *bc)
146 {
147 #ifdef BAYCOM_DEBUG
148 	unsigned long cur_jiffies = jiffies;
149 	/*
150 	 * measure the interrupt frequency
151 	 */
152 	bc->debug_vals.cur_intcnt++;
153 	if (time_after_eq(cur_jiffies, bc->debug_vals.last_jiffies + HZ)) {
154 		bc->debug_vals.last_jiffies = cur_jiffies;
155 		bc->debug_vals.last_intcnt = bc->debug_vals.cur_intcnt;
156 		bc->debug_vals.cur_intcnt = 0;
157 		bc->debug_vals.last_pllcorr = bc->debug_vals.cur_pllcorr;
158 		bc->debug_vals.cur_pllcorr = 0;
159 	}
160 #endif /* BAYCOM_DEBUG */
161 }
162 
163 /* --------------------------------------------------------------------- */
164 /*
165  * ===================== SER12 specific routines =========================
166  */
167 
168 /* --------------------------------------------------------------------- */
169 
170 static inline void ser12_set_divisor(struct net_device *dev,
171                                      unsigned int divisor)
172 {
173         outb(0x81, LCR(dev->base_addr));        /* DLAB = 1 */
174         outb(divisor, DLL(dev->base_addr));
175         outb(divisor >> 8, DLM(dev->base_addr));
176         outb(0x01, LCR(dev->base_addr));        /* word length = 6 */
177         /*
178          * make sure the next interrupt is generated;
179          * 0 must be used to power the modem; the modem draws its
180          * power from the TxD line
181          */
182         outb(0x00, THR(dev->base_addr));
183         /*
184          * it is important not to set the divider while transmitting;
185          * this reportedly makes some UARTs generating interrupts
186          * in the hundredthousands per second region
187          * Reported by: Ignacio.Arenaza@studi.epfl.ch (Ignacio Arenaza Nuno)
188          */
189 }
190 
191 static __inline__ void ser12_rx(struct net_device *dev, struct baycom_state *bc, struct timespec64 *ts, unsigned char curs)
192 {
193 	int timediff;
194 	int bdus8 = bc->baud_us >> 3;
195 	int bdus4 = bc->baud_us >> 2;
196 	int bdus2 = bc->baud_us >> 1;
197 
198 	timediff = 1000000 + ts->tv_nsec / NSEC_PER_USEC -
199 					bc->modem.ser12.pll_time;
200 	while (timediff >= 500000)
201 		timediff -= 1000000;
202 	while (timediff >= bdus2) {
203 		timediff -= bc->baud_us;
204 		bc->modem.ser12.pll_time += bc->baud_us;
205 		bc->modem.ser12.dcd_time--;
206 		/* first check if there is room to add a bit */
207 		if (bc->modem.shreg & 1) {
208 			hdlcdrv_putbits(&bc->hdrv, (bc->modem.shreg >> 1) ^ 0xffff);
209 			bc->modem.shreg = 0x10000;
210 		}
211 		/* add a one bit */
212 		bc->modem.shreg >>= 1;
213 	}
214 	if (bc->modem.ser12.dcd_time <= 0) {
215 		if (!bc->opt_dcd)
216 			hdlcdrv_setdcd(&bc->hdrv, (bc->modem.ser12.dcd_sum0 +
217 						   bc->modem.ser12.dcd_sum1 +
218 						   bc->modem.ser12.dcd_sum2) < 0);
219 		bc->modem.ser12.dcd_sum2 = bc->modem.ser12.dcd_sum1;
220 		bc->modem.ser12.dcd_sum1 = bc->modem.ser12.dcd_sum0;
221 		bc->modem.ser12.dcd_sum0 = 2; /* slight bias */
222 		bc->modem.ser12.dcd_time += 120;
223 	}
224 	if (bc->modem.ser12.last_rxbit != curs) {
225 		bc->modem.ser12.last_rxbit = curs;
226 		bc->modem.shreg |= 0x10000;
227 		/* adjust the PLL */
228 		if (timediff > 0)
229 			bc->modem.ser12.pll_time += bdus8;
230 		else
231 			bc->modem.ser12.pll_time += 1000000 - bdus8;
232 		/* update DCD */
233 		if (abs(timediff) > bdus4)
234 			bc->modem.ser12.dcd_sum0 += 4;
235 		else
236 			bc->modem.ser12.dcd_sum0--;
237 #ifdef BAYCOM_DEBUG
238 		bc->debug_vals.cur_pllcorr = timediff;
239 #endif /* BAYCOM_DEBUG */
240 	}
241 	while (bc->modem.ser12.pll_time >= 1000000)
242 		bc->modem.ser12.pll_time -= 1000000;
243 }
244 
245 /* --------------------------------------------------------------------- */
246 
247 static irqreturn_t ser12_interrupt(int irq, void *dev_id)
248 {
249 	struct net_device *dev = (struct net_device *)dev_id;
250 	struct baycom_state *bc = netdev_priv(dev);
251 	struct timespec64 ts;
252 	unsigned char iir, msr;
253 	unsigned int txcount = 0;
254 
255 	if (!bc || bc->hdrv.magic != HDLCDRV_MAGIC)
256 		return IRQ_NONE;
257 	/* fast way out for shared irq */
258 	if ((iir = inb(IIR(dev->base_addr))) & 1)
259 		return IRQ_NONE;
260 	/* get current time */
261 	ktime_get_ts64(&ts);
262 	msr = inb(MSR(dev->base_addr));
263 	/* delta DCD */
264 	if ((msr & 8) && bc->opt_dcd)
265 		hdlcdrv_setdcd(&bc->hdrv, !((msr ^ bc->opt_dcd) & 0x80));
266 	do {
267 		switch (iir & 6) {
268 		case 6:
269 			inb(LSR(dev->base_addr));
270 			break;
271 
272 		case 4:
273 			inb(RBR(dev->base_addr));
274 			break;
275 
276 		case 2:
277 			/*
278 			 * make sure the next interrupt is generated;
279 			 * 0 must be used to power the modem; the modem draws its
280 			 * power from the TxD line
281 			 */
282 			outb(0x00, THR(dev->base_addr));
283 			baycom_int_freq(bc);
284 			txcount++;
285 			/*
286 			 * first output the last bit (!) then call HDLC transmitter,
287 			 * since this may take quite long
288 			 */
289 			if (bc->modem.ptt)
290 				outb(0x0e | (!!bc->modem.ser12.tx_bit), MCR(dev->base_addr));
291 			else
292 				outb(0x0d, MCR(dev->base_addr));       /* transmitter off */
293 			break;
294 
295 		default:
296 			msr = inb(MSR(dev->base_addr));
297 			/* delta DCD */
298 			if ((msr & 8) && bc->opt_dcd)
299 				hdlcdrv_setdcd(&bc->hdrv, !((msr ^ bc->opt_dcd) & 0x80));
300 			break;
301 		}
302 		iir = inb(IIR(dev->base_addr));
303 	} while (!(iir & 1));
304 	ser12_rx(dev, bc, &ts, msr & 0x10); /* CTS */
305 	if (bc->modem.ptt && txcount) {
306 		if (bc->modem.ser12.txshreg <= 1) {
307 			bc->modem.ser12.txshreg = 0x10000 | hdlcdrv_getbits(&bc->hdrv);
308 			if (!hdlcdrv_ptt(&bc->hdrv)) {
309 				ser12_set_divisor(dev, 115200/100/8);
310 				bc->modem.ptt = 0;
311 				goto end_transmit;
312 			}
313 		}
314 		bc->modem.ser12.tx_bit = !(bc->modem.ser12.tx_bit ^ (bc->modem.ser12.txshreg & 1));
315 		bc->modem.ser12.txshreg >>= 1;
316 	}
317  end_transmit:
318 	local_irq_enable();
319 	if (!bc->modem.ptt && txcount) {
320 		hdlcdrv_arbitrate(dev, &bc->hdrv);
321 		if (hdlcdrv_ptt(&bc->hdrv)) {
322 			ser12_set_divisor(dev, bc->baud_uartdiv);
323 			bc->modem.ser12.txshreg = 1;
324 			bc->modem.ptt = 1;
325 		}
326 	}
327 	hdlcdrv_transmitter(dev, &bc->hdrv);
328 	hdlcdrv_receiver(dev, &bc->hdrv);
329 	local_irq_disable();
330 	return IRQ_HANDLED;
331 }
332 
333 /* --------------------------------------------------------------------- */
334 
335 enum uart { c_uart_unknown, c_uart_8250,
336 	    c_uart_16450, c_uart_16550, c_uart_16550A};
337 static const char *uart_str[] = {
338 	"unknown", "8250", "16450", "16550", "16550A"
339 };
340 
341 static enum uart ser12_check_uart(unsigned int iobase)
342 {
343 	unsigned char b1,b2,b3;
344 	enum uart u;
345 	enum uart uart_tab[] =
346 		{ c_uart_16450, c_uart_unknown, c_uart_16550, c_uart_16550A };
347 
348 	b1 = inb(MCR(iobase));
349 	outb(b1 | 0x10, MCR(iobase));	/* loopback mode */
350 	b2 = inb(MSR(iobase));
351 	outb(0x1a, MCR(iobase));
352 	b3 = inb(MSR(iobase)) & 0xf0;
353 	outb(b1, MCR(iobase));			/* restore old values */
354 	outb(b2, MSR(iobase));
355 	if (b3 != 0x90)
356 		return c_uart_unknown;
357 	inb(RBR(iobase));
358 	inb(RBR(iobase));
359 	outb(0x01, FCR(iobase));		/* enable FIFOs */
360 	u = uart_tab[(inb(IIR(iobase)) >> 6) & 3];
361 	if (u == c_uart_16450) {
362 		outb(0x5a, SCR(iobase));
363 		b1 = inb(SCR(iobase));
364 		outb(0xa5, SCR(iobase));
365 		b2 = inb(SCR(iobase));
366 		if ((b1 != 0x5a) || (b2 != 0xa5))
367 			u = c_uart_8250;
368 	}
369 	return u;
370 }
371 
372 /* --------------------------------------------------------------------- */
373 
374 static int ser12_open(struct net_device *dev)
375 {
376 	struct baycom_state *bc = netdev_priv(dev);
377 	enum uart u;
378 
379 	if (!dev || !bc)
380 		return -ENXIO;
381 	if (!dev->base_addr || dev->base_addr > 0xffff-SER12_EXTENT ||
382 	    dev->irq < 2 || dev->irq > nr_irqs) {
383 		printk(KERN_INFO "baycom_ser_fdx: invalid portnumber (max %u) "
384 				"or irq (2 <= irq <= %d)\n",
385 				0xffff-SER12_EXTENT, nr_irqs);
386 		return -ENXIO;
387 	}
388 	if (bc->baud < 300 || bc->baud > 4800) {
389 		printk(KERN_INFO "baycom_ser_fdx: invalid baudrate "
390 				"(300...4800)\n");
391 		return -EINVAL;
392 	}
393 	if (!request_region(dev->base_addr, SER12_EXTENT, "baycom_ser_fdx")) {
394 		printk(KERN_WARNING "BAYCOM_SER_FSX: I/O port 0x%04lx busy\n",
395 		       dev->base_addr);
396 		return -EACCES;
397 	}
398 	memset(&bc->modem, 0, sizeof(bc->modem));
399 	bc->hdrv.par.bitrate = bc->baud;
400 	bc->baud_us = 1000000/bc->baud;
401 	bc->baud_uartdiv = (115200/8)/bc->baud;
402 	if ((u = ser12_check_uart(dev->base_addr)) == c_uart_unknown){
403 		release_region(dev->base_addr, SER12_EXTENT);
404 		return -EIO;
405 	}
406 	outb(0, FCR(dev->base_addr));  /* disable FIFOs */
407 	outb(0x0d, MCR(dev->base_addr));
408 	outb(0, IER(dev->base_addr));
409 	if (request_irq(dev->irq, ser12_interrupt, IRQF_SHARED,
410 			"baycom_ser_fdx", dev)) {
411 		release_region(dev->base_addr, SER12_EXTENT);
412 		return -EBUSY;
413 	}
414 	/*
415 	 * set the SIO to 6 Bits/character; during receive,
416 	 * the baud rate is set to produce 100 ints/sec
417 	 * to feed the channel arbitration process,
418 	 * during transmit to baud ints/sec to run
419 	 * the transmitter
420 	 */
421 	ser12_set_divisor(dev, 115200/100/8);
422 	/*
423 	 * enable transmitter empty interrupt and modem status interrupt
424 	 */
425 	outb(0x0a, IER(dev->base_addr));
426 	/*
427 	 * make sure the next interrupt is generated;
428 	 * 0 must be used to power the modem; the modem draws its
429 	 * power from the TxD line
430 	 */
431 	outb(0x00, THR(dev->base_addr));
432 	hdlcdrv_setdcd(&bc->hdrv, 0);
433 	printk(KERN_INFO "%s: ser_fdx at iobase 0x%lx irq %u baud %u uart %s\n",
434 	       bc_drvname, dev->base_addr, dev->irq, bc->baud, uart_str[u]);
435 	return 0;
436 }
437 
438 /* --------------------------------------------------------------------- */
439 
440 static int ser12_close(struct net_device *dev)
441 {
442 	struct baycom_state *bc = netdev_priv(dev);
443 
444 	if (!dev || !bc)
445 		return -EINVAL;
446 	/*
447 	 * disable interrupts
448 	 */
449 	outb(0, IER(dev->base_addr));
450 	outb(1, MCR(dev->base_addr));
451 	free_irq(dev->irq, dev);
452 	release_region(dev->base_addr, SER12_EXTENT);
453 	printk(KERN_INFO "%s: close ser_fdx at iobase 0x%lx irq %u\n",
454 	       bc_drvname, dev->base_addr, dev->irq);
455 	return 0;
456 }
457 
458 /* --------------------------------------------------------------------- */
459 /*
460  * ===================== hdlcdrv driver interface =========================
461  */
462 
463 /* --------------------------------------------------------------------- */
464 
465 static int baycom_ioctl(struct net_device *dev, struct ifreq *ifr,
466 			struct hdlcdrv_ioctl *hi, int cmd);
467 
468 /* --------------------------------------------------------------------- */
469 
470 static const struct hdlcdrv_ops ser12_ops = {
471 	.drvname = bc_drvname,
472 	.drvinfo = bc_drvinfo,
473 	.open    = ser12_open,
474 	.close   = ser12_close,
475 	.ioctl   = baycom_ioctl,
476 };
477 
478 /* --------------------------------------------------------------------- */
479 
480 static int baycom_setmode(struct baycom_state *bc, const char *modestr)
481 {
482 	unsigned int baud;
483 
484 	if (!strncmp(modestr, "ser", 3)) {
485 		baud = simple_strtoul(modestr+3, NULL, 10);
486 		if (baud >= 3 && baud <= 48)
487 			bc->baud = baud*100;
488 	}
489 	if (strchr(modestr, '*'))
490 		bc->opt_dcd = 0;
491 	else if (strchr(modestr, '+'))
492 		bc->opt_dcd = -1;
493 	else
494 		bc->opt_dcd = 1;
495 	return 0;
496 }
497 
498 /* --------------------------------------------------------------------- */
499 
500 static int baycom_ioctl(struct net_device *dev, struct ifreq *ifr,
501 			struct hdlcdrv_ioctl *hi, int cmd)
502 {
503 	struct baycom_state *bc;
504 	struct baycom_ioctl bi;
505 
506 	if (!dev)
507 		return -EINVAL;
508 
509 	bc = netdev_priv(dev);
510 	BUG_ON(bc->hdrv.magic != HDLCDRV_MAGIC);
511 
512 	if (cmd != SIOCDEVPRIVATE)
513 		return -ENOIOCTLCMD;
514 	switch (hi->cmd) {
515 	default:
516 		break;
517 
518 	case HDLCDRVCTL_GETMODE:
519 		sprintf(hi->data.modename, "ser%u", bc->baud / 100);
520 		if (bc->opt_dcd <= 0)
521 			strcat(hi->data.modename, (!bc->opt_dcd) ? "*" : "+");
522 		if (copy_to_user(ifr->ifr_data, hi, sizeof(struct hdlcdrv_ioctl)))
523 			return -EFAULT;
524 		return 0;
525 
526 	case HDLCDRVCTL_SETMODE:
527 		if (netif_running(dev) || !capable(CAP_NET_ADMIN))
528 			return -EACCES;
529 		hi->data.modename[sizeof(hi->data.modename)-1] = '\0';
530 		return baycom_setmode(bc, hi->data.modename);
531 
532 	case HDLCDRVCTL_MODELIST:
533 		strcpy(hi->data.modename, "ser12,ser3,ser24");
534 		if (copy_to_user(ifr->ifr_data, hi, sizeof(struct hdlcdrv_ioctl)))
535 			return -EFAULT;
536 		return 0;
537 
538 	case HDLCDRVCTL_MODEMPARMASK:
539 		return HDLCDRV_PARMASK_IOBASE | HDLCDRV_PARMASK_IRQ;
540 
541 	}
542 
543 	if (copy_from_user(&bi, ifr->ifr_data, sizeof(bi)))
544 		return -EFAULT;
545 	switch (bi.cmd) {
546 	default:
547 		return -ENOIOCTLCMD;
548 
549 #ifdef BAYCOM_DEBUG
550 	case BAYCOMCTL_GETDEBUG:
551 		bi.data.dbg.debug1 = bc->hdrv.ptt_keyed;
552 		bi.data.dbg.debug2 = bc->debug_vals.last_intcnt;
553 		bi.data.dbg.debug3 = bc->debug_vals.last_pllcorr;
554 		break;
555 #endif /* BAYCOM_DEBUG */
556 
557 	}
558 	if (copy_to_user(ifr->ifr_data, &bi, sizeof(bi)))
559 		return -EFAULT;
560 	return 0;
561 
562 }
563 
564 /* --------------------------------------------------------------------- */
565 
566 /*
567  * command line settable parameters
568  */
569 static char *mode[NR_PORTS] = { "ser12*", };
570 static int iobase[NR_PORTS] = { 0x3f8, };
571 static int irq[NR_PORTS] = { 4, };
572 static int baud[NR_PORTS] = { [0 ... NR_PORTS-1] = 1200 };
573 
574 module_param_array(mode, charp, NULL, 0);
575 MODULE_PARM_DESC(mode, "baycom operating mode; * for software DCD");
576 module_param_hw_array(iobase, int, ioport, NULL, 0);
577 MODULE_PARM_DESC(iobase, "baycom io base address");
578 module_param_hw_array(irq, int, irq, NULL, 0);
579 MODULE_PARM_DESC(irq, "baycom irq number");
580 module_param_array(baud, int, NULL, 0);
581 MODULE_PARM_DESC(baud, "baycom baud rate (300 to 4800)");
582 
583 MODULE_AUTHOR("Thomas M. Sailer, sailer@ife.ee.ethz.ch, hb9jnx@hb9w.che.eu");
584 MODULE_DESCRIPTION("Baycom ser12 full duplex amateur radio modem driver");
585 MODULE_LICENSE("GPL");
586 
587 /* --------------------------------------------------------------------- */
588 
589 static int __init init_baycomserfdx(void)
590 {
591 	int i, found = 0;
592 	char set_hw = 1;
593 
594 	printk(bc_drvinfo);
595 	/*
596 	 * register net devices
597 	 */
598 	for (i = 0; i < NR_PORTS; i++) {
599 		struct net_device *dev;
600 		struct baycom_state *bc;
601 		char ifname[IFNAMSIZ];
602 
603 		sprintf(ifname, "bcsf%d", i);
604 
605 		if (!mode[i])
606 			set_hw = 0;
607 		if (!set_hw)
608 			iobase[i] = irq[i] = 0;
609 
610 		dev = hdlcdrv_register(&ser12_ops,
611 				       sizeof(struct baycom_state),
612 				       ifname, iobase[i], irq[i], 0);
613 		if (IS_ERR(dev))
614 			break;
615 
616 		bc = netdev_priv(dev);
617 		if (set_hw && baycom_setmode(bc, mode[i]))
618 			set_hw = 0;
619 		bc->baud = baud[i];
620 		found++;
621 		baycom_device[i] = dev;
622 	}
623 
624 	if (!found)
625 		return -ENXIO;
626 	return 0;
627 }
628 
629 static void __exit cleanup_baycomserfdx(void)
630 {
631 	int i;
632 
633 	for(i = 0; i < NR_PORTS; i++) {
634 		struct net_device *dev = baycom_device[i];
635 		if (dev)
636 			hdlcdrv_unregister(dev);
637 	}
638 }
639 
640 module_init(init_baycomserfdx);
641 module_exit(cleanup_baycomserfdx);
642 
643 /* --------------------------------------------------------------------- */
644 
645 #ifndef MODULE
646 
647 /*
648  * format: baycom_ser_fdx=io,irq,mode
649  * mode: ser#    hardware DCD
650  *       ser#*   software DCD
651  *       ser#+   hardware DCD, inverted signal at DCD pin
652  * '#' denotes the baud rate / 100, eg. ser12* is '1200 baud, soft DCD'
653  */
654 
655 static int __init baycom_ser_fdx_setup(char *str)
656 {
657         static unsigned nr_dev;
658         int ints[4];
659 
660         if (nr_dev >= NR_PORTS)
661                 return 0;
662         str = get_options(str, 4, ints);
663         if (ints[0] < 2)
664                 return 0;
665         mode[nr_dev] = str;
666         iobase[nr_dev] = ints[1];
667         irq[nr_dev] = ints[2];
668 	if (ints[0] >= 3)
669 		baud[nr_dev] = ints[3];
670 	nr_dev++;
671 	return 1;
672 }
673 
674 __setup("baycom_ser_fdx=", baycom_ser_fdx_setup);
675 
676 #endif /* MODULE */
677 /* --------------------------------------------------------------------- */
678