1 /*****************************************************************************/
2 
3 /*
4  *	baycom_ser_hdx.c  -- baycom ser12 halfduplex radio modem driver.
5  *
6  *	Copyright (C) 1996-2000  Thomas Sailer (sailer@ife.ee.ethz.ch)
7  *
8  *	This program is free software; you can redistribute it and/or modify
9  *	it under the terms of the GNU General Public License as published by
10  *	the Free Software Foundation; either version 2 of the License, or
11  *	(at your option) any later version.
12  *
13  *	This program is distributed in the hope that it will be useful,
14  *	but WITHOUT ANY WARRANTY; without even the implied warranty of
15  *	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  *	GNU General Public License for more details.
17  *
18  *	You should have received a copy of the GNU General Public License
19  *	along with this program; if not, write to the Free Software
20  *	Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
21  *
22  *  Please note that the GPL allows you to use the driver, NOT the radio.
23  *  In order to use the radio, you need a license from the communications
24  *  authority of your country.
25  *
26  *
27  *  Supported modems
28  *
29  *  ser12:  This is a very simple 1200 baud AFSK modem. The modem consists only
30  *          of a modulator/demodulator chip, usually a TI TCM3105. The computer
31  *          is responsible for regenerating the receiver bit clock, as well as
32  *          for handling the HDLC protocol. The modem connects to a serial port,
33  *          hence the name. Since the serial port is not used as an async serial
34  *          port, the kernel driver for serial ports cannot be used, and this
35  *          driver only supports standard serial hardware (8250, 16450, 16550A)
36  *
37  *
38  *  Command line options (insmod command line)
39  *
40  *  mode     ser12    hardware DCD
41  *           ser12*   software DCD
42  *           ser12@   hardware/software DCD, i.e. no explicit DCD signal but hardware
43  *                    mutes audio input to the modem
44  *           ser12+   hardware DCD, inverted signal at DCD pin
45  *  iobase   base address of the port; common values are 0x3f8, 0x2f8, 0x3e8, 0x2e8
46  *  irq      interrupt line of the port; common values are 4,3
47  *
48  *
49  *  History:
50  *   0.1  26.06.1996  Adapted from baycom.c and made network driver interface
51  *        18.10.1996  Changed to new user space access routines (copy_{to,from}_user)
52  *   0.3  26.04.1997  init code/data tagged
53  *   0.4  08.07.1997  alternative ser12 decoding algorithm (uses delta CTS ints)
54  *   0.5  11.11.1997  ser12/par96 split into separate files
55  *   0.6  14.04.1998  cleanups
56  *   0.7  03.08.1999  adapt to Linus' new __setup/__initcall
57  *   0.8  10.08.1999  use module_init/module_exit
58  *   0.9  12.02.2000  adapted to softnet driver interface
59  *   0.10 03.07.2000  fix interface name handling
60  */
61 
62 /*****************************************************************************/
63 
64 #include <linux/module.h>
65 #include <linux/ioport.h>
66 #include <linux/string.h>
67 #include <linux/init.h>
68 #include <asm/uaccess.h>
69 #include <asm/io.h>
70 #include <linux/hdlcdrv.h>
71 #include <linux/baycom.h>
72 #include <linux/jiffies.h>
73 
74 /* --------------------------------------------------------------------- */
75 
76 #define BAYCOM_DEBUG
77 
78 /* --------------------------------------------------------------------- */
79 
80 static const char bc_drvname[] = "baycom_ser_hdx";
81 static const char bc_drvinfo[] = KERN_INFO "baycom_ser_hdx: (C) 1996-2000 Thomas Sailer, HB9JNX/AE4WA\n"
82 KERN_INFO "baycom_ser_hdx: version 0.10 compiled " __TIME__ " " __DATE__ "\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 	int opt_dcd;
116 
117 	struct modem_state {
118 		short arb_divider;
119 		unsigned char flags;
120 		unsigned int shreg;
121 		struct modem_state_ser12 {
122 			unsigned char tx_bit;
123 			int dcd_sum0, dcd_sum1, dcd_sum2;
124 			unsigned char last_sample;
125 			unsigned char last_rxbit;
126 			unsigned int dcd_shreg;
127 			unsigned int dcd_time;
128 			unsigned int bit_pll;
129 			unsigned char interm_sample;
130 		} ser12;
131 	} modem;
132 
133 #ifdef BAYCOM_DEBUG
134 	struct debug_vals {
135 		unsigned long last_jiffies;
136 		unsigned cur_intcnt;
137 		unsigned last_intcnt;
138 		int cur_pllcorr;
139 		int last_pllcorr;
140 	} debug_vals;
141 #endif /* BAYCOM_DEBUG */
142 };
143 
144 /* --------------------------------------------------------------------- */
145 
146 static inline void baycom_int_freq(struct baycom_state *bc)
147 {
148 #ifdef BAYCOM_DEBUG
149 	unsigned long cur_jiffies = jiffies;
150 	/*
151 	 * measure the interrupt frequency
152 	 */
153 	bc->debug_vals.cur_intcnt++;
154 	if (time_after_eq(cur_jiffies, bc->debug_vals.last_jiffies + HZ)) {
155 		bc->debug_vals.last_jiffies = cur_jiffies;
156 		bc->debug_vals.last_intcnt = bc->debug_vals.cur_intcnt;
157 		bc->debug_vals.cur_intcnt = 0;
158 		bc->debug_vals.last_pllcorr = bc->debug_vals.cur_pllcorr;
159 		bc->debug_vals.cur_pllcorr = 0;
160 	}
161 #endif /* BAYCOM_DEBUG */
162 }
163 
164 /* --------------------------------------------------------------------- */
165 /*
166  * ===================== SER12 specific routines =========================
167  */
168 
169 static inline void ser12_set_divisor(struct net_device *dev,
170 				     unsigned char divisor)
171 {
172 	outb(0x81, LCR(dev->base_addr));	/* DLAB = 1 */
173 	outb(divisor, DLL(dev->base_addr));
174 	outb(0, DLM(dev->base_addr));
175 	outb(0x01, LCR(dev->base_addr));	/* word length = 6 */
176 	/*
177 	 * make sure the next interrupt is generated;
178 	 * 0 must be used to power the modem; the modem draws its
179 	 * power from the TxD line
180 	 */
181 	outb(0x00, THR(dev->base_addr));
182 	/*
183 	 * it is important not to set the divider while transmitting;
184 	 * this reportedly makes some UARTs generating interrupts
185 	 * in the hundredthousands per second region
186 	 * Reported by: Ignacio.Arenaza@studi.epfl.ch (Ignacio Arenaza Nuno)
187 	 */
188 }
189 
190 /* --------------------------------------------------------------------- */
191 
192 /*
193  * must call the TX arbitrator every 10ms
194  */
195 #define SER12_ARB_DIVIDER(bc)  (bc->opt_dcd ? 24 : 36)
196 
197 #define SER12_DCD_INTERVAL(bc) (bc->opt_dcd ? 12 : 240)
198 
199 static inline void ser12_tx(struct net_device *dev, struct baycom_state *bc)
200 {
201 	/* one interrupt per channel bit */
202 	ser12_set_divisor(dev, 12);
203 	/*
204 	 * first output the last bit (!) then call HDLC transmitter,
205 	 * since this may take quite long
206 	 */
207 	outb(0x0e | (!!bc->modem.ser12.tx_bit), MCR(dev->base_addr));
208 	if (bc->modem.shreg <= 1)
209 		bc->modem.shreg = 0x10000 | hdlcdrv_getbits(&bc->hdrv);
210 	bc->modem.ser12.tx_bit = !(bc->modem.ser12.tx_bit ^
211 				   (bc->modem.shreg & 1));
212 	bc->modem.shreg >>= 1;
213 }
214 
215 /* --------------------------------------------------------------------- */
216 
217 static inline void ser12_rx(struct net_device *dev, struct baycom_state *bc)
218 {
219 	unsigned char cur_s;
220 	/*
221 	 * do demodulator
222 	 */
223 	cur_s = inb(MSR(dev->base_addr)) & 0x10;	/* the CTS line */
224 	hdlcdrv_channelbit(&bc->hdrv, cur_s);
225 	bc->modem.ser12.dcd_shreg = (bc->modem.ser12.dcd_shreg << 1) |
226 		(cur_s != bc->modem.ser12.last_sample);
227 	bc->modem.ser12.last_sample = cur_s;
228 	if(bc->modem.ser12.dcd_shreg & 1) {
229 		if (!bc->opt_dcd) {
230 			unsigned int dcdspos, dcdsneg;
231 
232 			dcdspos = dcdsneg = 0;
233 			dcdspos += ((bc->modem.ser12.dcd_shreg >> 1) & 1);
234 			if (!(bc->modem.ser12.dcd_shreg & 0x7ffffffe))
235 				dcdspos += 2;
236 			dcdsneg += ((bc->modem.ser12.dcd_shreg >> 2) & 1);
237 			dcdsneg += ((bc->modem.ser12.dcd_shreg >> 3) & 1);
238 			dcdsneg += ((bc->modem.ser12.dcd_shreg >> 4) & 1);
239 
240 			bc->modem.ser12.dcd_sum0 += 16*dcdspos - dcdsneg;
241 		} else
242 			bc->modem.ser12.dcd_sum0--;
243 	}
244 	if(!bc->modem.ser12.dcd_time) {
245 		hdlcdrv_setdcd(&bc->hdrv, (bc->modem.ser12.dcd_sum0 +
246 					   bc->modem.ser12.dcd_sum1 +
247 					   bc->modem.ser12.dcd_sum2) < 0);
248 		bc->modem.ser12.dcd_sum2 = bc->modem.ser12.dcd_sum1;
249 		bc->modem.ser12.dcd_sum1 = bc->modem.ser12.dcd_sum0;
250 		/* offset to ensure DCD off on silent input */
251 		bc->modem.ser12.dcd_sum0 = 2;
252 		bc->modem.ser12.dcd_time = SER12_DCD_INTERVAL(bc);
253 	}
254 	bc->modem.ser12.dcd_time--;
255 	if (!bc->opt_dcd) {
256 		/*
257 		 * PLL code for the improved software DCD algorithm
258 		 */
259 		if (bc->modem.ser12.interm_sample) {
260 			/*
261 			 * intermediate sample; set timing correction to normal
262 			 */
263 			ser12_set_divisor(dev, 4);
264 		} else {
265 			/*
266 			 * do PLL correction and call HDLC receiver
267 			 */
268 			switch (bc->modem.ser12.dcd_shreg & 7) {
269 			case 1: /* transition too late */
270 				ser12_set_divisor(dev, 5);
271 #ifdef BAYCOM_DEBUG
272 				bc->debug_vals.cur_pllcorr++;
273 #endif /* BAYCOM_DEBUG */
274 				break;
275 			case 4:	/* transition too early */
276 				ser12_set_divisor(dev, 3);
277 #ifdef BAYCOM_DEBUG
278 				bc->debug_vals.cur_pllcorr--;
279 #endif /* BAYCOM_DEBUG */
280 				break;
281 			default:
282 				ser12_set_divisor(dev, 4);
283 				break;
284 			}
285 			bc->modem.shreg >>= 1;
286 			if (bc->modem.ser12.last_sample ==
287 			    bc->modem.ser12.last_rxbit)
288 				bc->modem.shreg |= 0x10000;
289 			bc->modem.ser12.last_rxbit =
290 				bc->modem.ser12.last_sample;
291 		}
292 		if (++bc->modem.ser12.interm_sample >= 3)
293 			bc->modem.ser12.interm_sample = 0;
294 		/*
295 		 * DCD stuff
296 		 */
297 		if (bc->modem.ser12.dcd_shreg & 1) {
298 			unsigned int dcdspos, dcdsneg;
299 
300 			dcdspos = dcdsneg = 0;
301 			dcdspos += ((bc->modem.ser12.dcd_shreg >> 1) & 1);
302 			dcdspos += (!(bc->modem.ser12.dcd_shreg & 0x7ffffffe))
303 				<< 1;
304 			dcdsneg += ((bc->modem.ser12.dcd_shreg >> 2) & 1);
305 			dcdsneg += ((bc->modem.ser12.dcd_shreg >> 3) & 1);
306 			dcdsneg += ((bc->modem.ser12.dcd_shreg >> 4) & 1);
307 
308 			bc->modem.ser12.dcd_sum0 += 16*dcdspos - dcdsneg;
309 		}
310 	} else {
311 		/*
312 		 * PLL algorithm for the hardware squelch DCD algorithm
313 		 */
314 		if (bc->modem.ser12.interm_sample) {
315 			/*
316 			 * intermediate sample; set timing correction to normal
317 			 */
318 			ser12_set_divisor(dev, 6);
319 		} else {
320 			/*
321 			 * do PLL correction and call HDLC receiver
322 			 */
323 			switch (bc->modem.ser12.dcd_shreg & 3) {
324 			case 1: /* transition too late */
325 				ser12_set_divisor(dev, 7);
326 #ifdef BAYCOM_DEBUG
327 				bc->debug_vals.cur_pllcorr++;
328 #endif /* BAYCOM_DEBUG */
329 				break;
330 			case 2:	/* transition too early */
331 				ser12_set_divisor(dev, 5);
332 #ifdef BAYCOM_DEBUG
333 				bc->debug_vals.cur_pllcorr--;
334 #endif /* BAYCOM_DEBUG */
335 				break;
336 			default:
337 				ser12_set_divisor(dev, 6);
338 				break;
339 			}
340 			bc->modem.shreg >>= 1;
341 			if (bc->modem.ser12.last_sample ==
342 			    bc->modem.ser12.last_rxbit)
343 				bc->modem.shreg |= 0x10000;
344 			bc->modem.ser12.last_rxbit =
345 				bc->modem.ser12.last_sample;
346 		}
347 		bc->modem.ser12.interm_sample = !bc->modem.ser12.interm_sample;
348 		/*
349 		 * DCD stuff
350 		 */
351 		bc->modem.ser12.dcd_sum0 -= (bc->modem.ser12.dcd_shreg & 1);
352 	}
353 	outb(0x0d, MCR(dev->base_addr));		/* transmitter off */
354 	if (bc->modem.shreg & 1) {
355 		hdlcdrv_putbits(&bc->hdrv, bc->modem.shreg >> 1);
356 		bc->modem.shreg = 0x10000;
357 	}
358 	if(!bc->modem.ser12.dcd_time) {
359 		if (bc->opt_dcd & 1)
360 			hdlcdrv_setdcd(&bc->hdrv, !((inb(MSR(dev->base_addr)) ^ bc->opt_dcd) & 0x80));
361 		else
362 			hdlcdrv_setdcd(&bc->hdrv, (bc->modem.ser12.dcd_sum0 +
363 						   bc->modem.ser12.dcd_sum1 +
364 						   bc->modem.ser12.dcd_sum2) < 0);
365 		bc->modem.ser12.dcd_sum2 = bc->modem.ser12.dcd_sum1;
366 		bc->modem.ser12.dcd_sum1 = bc->modem.ser12.dcd_sum0;
367 		/* offset to ensure DCD off on silent input */
368 		bc->modem.ser12.dcd_sum0 = 2;
369 		bc->modem.ser12.dcd_time = SER12_DCD_INTERVAL(bc);
370 	}
371 	bc->modem.ser12.dcd_time--;
372 }
373 
374 /* --------------------------------------------------------------------- */
375 
376 static irqreturn_t ser12_interrupt(int irq, void *dev_id)
377 {
378 	struct net_device *dev = (struct net_device *)dev_id;
379 	struct baycom_state *bc = netdev_priv(dev);
380 	unsigned char iir;
381 
382 	if (!dev || !bc || bc->hdrv.magic != HDLCDRV_MAGIC)
383 		return IRQ_NONE;
384 	/* fast way out */
385 	if ((iir = inb(IIR(dev->base_addr))) & 1)
386 		return IRQ_NONE;
387 	baycom_int_freq(bc);
388 	do {
389 		switch (iir & 6) {
390 		case 6:
391 			inb(LSR(dev->base_addr));
392 			break;
393 
394 		case 4:
395 			inb(RBR(dev->base_addr));
396 			break;
397 
398 		case 2:
399 			/*
400 			 * check if transmitter active
401 			 */
402 			if (hdlcdrv_ptt(&bc->hdrv))
403 				ser12_tx(dev, bc);
404 			else {
405 				ser12_rx(dev, bc);
406 				bc->modem.arb_divider--;
407 			}
408 			outb(0x00, THR(dev->base_addr));
409 			break;
410 
411 		default:
412 			inb(MSR(dev->base_addr));
413 			break;
414 		}
415 		iir = inb(IIR(dev->base_addr));
416 	} while (!(iir & 1));
417 	if (bc->modem.arb_divider <= 0) {
418 		bc->modem.arb_divider = SER12_ARB_DIVIDER(bc);
419 		local_irq_enable();
420 		hdlcdrv_arbitrate(dev, &bc->hdrv);
421 	}
422 	local_irq_enable();
423 	hdlcdrv_transmitter(dev, &bc->hdrv);
424 	hdlcdrv_receiver(dev, &bc->hdrv);
425 	local_irq_disable();
426 	return IRQ_HANDLED;
427 }
428 
429 /* --------------------------------------------------------------------- */
430 
431 enum uart { c_uart_unknown, c_uart_8250,
432 	    c_uart_16450, c_uart_16550, c_uart_16550A};
433 static const char *uart_str[] = {
434 	"unknown", "8250", "16450", "16550", "16550A"
435 };
436 
437 static enum uart ser12_check_uart(unsigned int iobase)
438 {
439 	unsigned char b1,b2,b3;
440 	enum uart u;
441 	enum uart uart_tab[] =
442 		{ c_uart_16450, c_uart_unknown, c_uart_16550, c_uart_16550A };
443 
444 	b1 = inb(MCR(iobase));
445 	outb(b1 | 0x10, MCR(iobase));	/* loopback mode */
446 	b2 = inb(MSR(iobase));
447 	outb(0x1a, MCR(iobase));
448 	b3 = inb(MSR(iobase)) & 0xf0;
449 	outb(b1, MCR(iobase));			/* restore old values */
450 	outb(b2, MSR(iobase));
451 	if (b3 != 0x90)
452 		return c_uart_unknown;
453 	inb(RBR(iobase));
454 	inb(RBR(iobase));
455 	outb(0x01, FCR(iobase));		/* enable FIFOs */
456 	u = uart_tab[(inb(IIR(iobase)) >> 6) & 3];
457 	if (u == c_uart_16450) {
458 		outb(0x5a, SCR(iobase));
459 		b1 = inb(SCR(iobase));
460 		outb(0xa5, SCR(iobase));
461 		b2 = inb(SCR(iobase));
462 		if ((b1 != 0x5a) || (b2 != 0xa5))
463 			u = c_uart_8250;
464 	}
465 	return u;
466 }
467 
468 /* --------------------------------------------------------------------- */
469 
470 static int ser12_open(struct net_device *dev)
471 {
472 	struct baycom_state *bc = netdev_priv(dev);
473 	enum uart u;
474 
475 	if (!dev || !bc)
476 		return -ENXIO;
477 	if (!dev->base_addr || dev->base_addr > 0x1000-SER12_EXTENT ||
478 	    dev->irq < 2 || dev->irq > 15)
479 		return -ENXIO;
480 	if (!request_region(dev->base_addr, SER12_EXTENT, "baycom_ser12"))
481 		return -EACCES;
482 	memset(&bc->modem, 0, sizeof(bc->modem));
483 	bc->hdrv.par.bitrate = 1200;
484 	if ((u = ser12_check_uart(dev->base_addr)) == c_uart_unknown) {
485 		release_region(dev->base_addr, SER12_EXTENT);
486 		return -EIO;
487 	}
488 	outb(0, FCR(dev->base_addr));  /* disable FIFOs */
489 	outb(0x0d, MCR(dev->base_addr));
490 	outb(0, IER(dev->base_addr));
491 	if (request_irq(dev->irq, ser12_interrupt, IRQF_DISABLED | IRQF_SHARED,
492 			"baycom_ser12", dev)) {
493 		release_region(dev->base_addr, SER12_EXTENT);
494 		return -EBUSY;
495 	}
496 	/*
497 	 * enable transmitter empty interrupt
498 	 */
499 	outb(2, IER(dev->base_addr));
500 	/*
501 	 * set the SIO to 6 Bits/character and 19200 or 28800 baud, so that
502 	 * we get exactly (hopefully) 2 or 3 interrupts per radio symbol,
503 	 * depending on the usage of the software DCD routine
504 	 */
505 	ser12_set_divisor(dev, bc->opt_dcd ? 6 : 4);
506 	printk(KERN_INFO "%s: ser12 at iobase 0x%lx irq %u uart %s\n",
507 	       bc_drvname, dev->base_addr, dev->irq, uart_str[u]);
508 	return 0;
509 }
510 
511 /* --------------------------------------------------------------------- */
512 
513 static int ser12_close(struct net_device *dev)
514 {
515 	struct baycom_state *bc = netdev_priv(dev);
516 
517 	if (!dev || !bc)
518 		return -EINVAL;
519 	/*
520 	 * disable interrupts
521 	 */
522 	outb(0, IER(dev->base_addr));
523 	outb(1, MCR(dev->base_addr));
524 	free_irq(dev->irq, dev);
525 	release_region(dev->base_addr, SER12_EXTENT);
526 	printk(KERN_INFO "%s: close ser12 at iobase 0x%lx irq %u\n",
527 	       bc_drvname, dev->base_addr, dev->irq);
528 	return 0;
529 }
530 
531 /* --------------------------------------------------------------------- */
532 /*
533  * ===================== hdlcdrv driver interface =========================
534  */
535 
536 /* --------------------------------------------------------------------- */
537 
538 static int baycom_ioctl(struct net_device *dev, struct ifreq *ifr,
539 			struct hdlcdrv_ioctl *hi, int cmd);
540 
541 /* --------------------------------------------------------------------- */
542 
543 static struct hdlcdrv_ops ser12_ops = {
544 	.drvname = bc_drvname,
545 	.drvinfo = bc_drvinfo,
546 	.open    = ser12_open,
547 	.close   = ser12_close,
548 	.ioctl   = baycom_ioctl,
549 };
550 
551 /* --------------------------------------------------------------------- */
552 
553 static int baycom_setmode(struct baycom_state *bc, const char *modestr)
554 {
555 	if (strchr(modestr, '*'))
556 		bc->opt_dcd = 0;
557 	else if (strchr(modestr, '+'))
558 		bc->opt_dcd = -1;
559 	else if (strchr(modestr, '@'))
560 		bc->opt_dcd = -2;
561 	else
562 		bc->opt_dcd = 1;
563 	return 0;
564 }
565 
566 /* --------------------------------------------------------------------- */
567 
568 static int baycom_ioctl(struct net_device *dev, struct ifreq *ifr,
569 			struct hdlcdrv_ioctl *hi, int cmd)
570 {
571 	struct baycom_state *bc;
572 	struct baycom_ioctl bi;
573 
574 	if (!dev)
575 		return -EINVAL;
576 
577 	bc = netdev_priv(dev);
578 	BUG_ON(bc->hdrv.magic != HDLCDRV_MAGIC);
579 
580 	if (cmd != SIOCDEVPRIVATE)
581 		return -ENOIOCTLCMD;
582 	switch (hi->cmd) {
583 	default:
584 		break;
585 
586 	case HDLCDRVCTL_GETMODE:
587 		strcpy(hi->data.modename, "ser12");
588 		if (bc->opt_dcd <= 0)
589 			strcat(hi->data.modename, (!bc->opt_dcd) ? "*" : (bc->opt_dcd == -2) ? "@" : "+");
590 		if (copy_to_user(ifr->ifr_data, hi, sizeof(struct hdlcdrv_ioctl)))
591 			return -EFAULT;
592 		return 0;
593 
594 	case HDLCDRVCTL_SETMODE:
595 		if (netif_running(dev) || !capable(CAP_NET_ADMIN))
596 			return -EACCES;
597 		hi->data.modename[sizeof(hi->data.modename)-1] = '\0';
598 		return baycom_setmode(bc, hi->data.modename);
599 
600 	case HDLCDRVCTL_MODELIST:
601 		strcpy(hi->data.modename, "ser12");
602 		if (copy_to_user(ifr->ifr_data, hi, sizeof(struct hdlcdrv_ioctl)))
603 			return -EFAULT;
604 		return 0;
605 
606 	case HDLCDRVCTL_MODEMPARMASK:
607 		return HDLCDRV_PARMASK_IOBASE | HDLCDRV_PARMASK_IRQ;
608 
609 	}
610 
611 	if (copy_from_user(&bi, ifr->ifr_data, sizeof(bi)))
612 		return -EFAULT;
613 	switch (bi.cmd) {
614 	default:
615 		return -ENOIOCTLCMD;
616 
617 #ifdef BAYCOM_DEBUG
618 	case BAYCOMCTL_GETDEBUG:
619 		bi.data.dbg.debug1 = bc->hdrv.ptt_keyed;
620 		bi.data.dbg.debug2 = bc->debug_vals.last_intcnt;
621 		bi.data.dbg.debug3 = bc->debug_vals.last_pllcorr;
622 		break;
623 #endif /* BAYCOM_DEBUG */
624 
625 	}
626 	if (copy_to_user(ifr->ifr_data, &bi, sizeof(bi)))
627 		return -EFAULT;
628 	return 0;
629 
630 }
631 
632 /* --------------------------------------------------------------------- */
633 
634 /*
635  * command line settable parameters
636  */
637 static char *mode[NR_PORTS] = { "ser12*", };
638 static int iobase[NR_PORTS] = { 0x3f8, };
639 static int irq[NR_PORTS] = { 4, };
640 
641 module_param_array(mode, charp, NULL, 0);
642 MODULE_PARM_DESC(mode, "baycom operating mode; * for software DCD");
643 module_param_array(iobase, int, NULL, 0);
644 MODULE_PARM_DESC(iobase, "baycom io base address");
645 module_param_array(irq, int, NULL, 0);
646 MODULE_PARM_DESC(irq, "baycom irq number");
647 
648 MODULE_AUTHOR("Thomas M. Sailer, sailer@ife.ee.ethz.ch, hb9jnx@hb9w.che.eu");
649 MODULE_DESCRIPTION("Baycom ser12 half duplex amateur radio modem driver");
650 MODULE_LICENSE("GPL");
651 
652 /* --------------------------------------------------------------------- */
653 
654 static int __init init_baycomserhdx(void)
655 {
656 	int i, found = 0;
657 	char set_hw = 1;
658 
659 	printk(bc_drvinfo);
660 	/*
661 	 * register net devices
662 	 */
663 	for (i = 0; i < NR_PORTS; i++) {
664 		struct net_device *dev;
665 		struct baycom_state *bc;
666 		char ifname[IFNAMSIZ];
667 
668 		sprintf(ifname, "bcsh%d", i);
669 
670 		if (!mode[i])
671 			set_hw = 0;
672 		if (!set_hw)
673 			iobase[i] = irq[i] = 0;
674 
675 		dev = hdlcdrv_register(&ser12_ops,
676 				       sizeof(struct baycom_state),
677 				       ifname, iobase[i], irq[i], 0);
678 		if (IS_ERR(dev))
679 			break;
680 
681 		bc = netdev_priv(dev);
682 		if (set_hw && baycom_setmode(bc, mode[i]))
683 			set_hw = 0;
684 		found++;
685 		baycom_device[i] = dev;
686 	}
687 
688 	if (!found)
689 		return -ENXIO;
690 	return 0;
691 }
692 
693 static void __exit cleanup_baycomserhdx(void)
694 {
695 	int i;
696 
697 	for(i = 0; i < NR_PORTS; i++) {
698 		struct net_device *dev = baycom_device[i];
699 
700 		if (dev)
701 			hdlcdrv_unregister(dev);
702 	}
703 }
704 
705 module_init(init_baycomserhdx);
706 module_exit(cleanup_baycomserhdx);
707 
708 /* --------------------------------------------------------------------- */
709 
710 #ifndef MODULE
711 
712 /*
713  * format: baycom_ser_hdx=io,irq,mode
714  * mode: ser12    hardware DCD
715  *       ser12*   software DCD
716  *       ser12@   hardware/software DCD, i.e. no explicit DCD signal but hardware
717  *                mutes audio input to the modem
718  *       ser12+   hardware DCD, inverted signal at DCD pin
719  */
720 
721 static int __init baycom_ser_hdx_setup(char *str)
722 {
723         static unsigned nr_dev;
724 	int ints[3];
725 
726         if (nr_dev >= NR_PORTS)
727                 return 0;
728 	str = get_options(str, 3, ints);
729 	if (ints[0] < 2)
730 		return 0;
731 	mode[nr_dev] = str;
732 	iobase[nr_dev] = ints[1];
733 	irq[nr_dev] = ints[2];
734 	nr_dev++;
735 	return 1;
736 }
737 
738 __setup("baycom_ser_hdx=", baycom_ser_hdx_setup);
739 
740 #endif /* MODULE */
741 /* --------------------------------------------------------------------- */
742