1 /*****************************************************************************/
2
3 /*
4 * baycom_par.c -- baycom par96 and picpar 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 * par96: This is a modem for 9600 baud FSK compatible to the G3RUH standard.
30 * The modem does all the filtering and regenerates the receiver clock.
31 * Data is transferred from and to the PC via a shift register.
32 * The shift register is filled with 16 bits and an interrupt is
33 * signalled. The PC then empties the shift register in a burst. This
34 * modem connects to the parallel port, hence the name. The modem
35 * leaves the implementation of the HDLC protocol and the scrambler
36 * polynomial to the PC. This modem is no longer available (at least
37 * from Baycom) and has been replaced by the PICPAR modem (see below).
38 * You may however still build one from the schematics published in
39 * cq-DL :-).
40 *
41 * picpar: This is a redesign of the par96 modem by Henning Rech, DF9IC. The
42 * modem is protocol compatible to par96, but uses only three low
43 * power ICs and can therefore be fed from the parallel port and
44 * does not require an additional power supply. It features
45 * built in DCD circuitry. The driver should therefore be configured
46 * for hardware DCD.
47 *
48 *
49 * Command line options (insmod command line)
50 *
51 * mode driver mode string. Valid choices are par96 and picpar.
52 * iobase base address of the port; common values are 0x378, 0x278, 0x3bc
53 *
54 *
55 * History:
56 * 0.1 26.06.1996 Adapted from baycom.c and made network driver interface
57 * 18.10.1996 Changed to new user space access routines (copy_{to,from}_user)
58 * 0.3 26.04.1997 init code/data tagged
59 * 0.4 08.07.1997 alternative ser12 decoding algorithm (uses delta CTS ints)
60 * 0.5 11.11.1997 split into separate files for ser12/par96
61 * 0.6 03.08.1999 adapt to Linus' new __setup/__initcall
62 * removed some pre-2.2 kernel compatibility cruft
63 * 0.7 10.08.1999 Check if parport can do SPP and is safe to access during interrupt contexts
64 * 0.8 12.02.2000 adapted to softnet driver interface
65 * removed direct parport access, uses parport driver methods
66 * 0.9 03.07.2000 fix interface name handling
67 */
68
69 /*****************************************************************************/
70
71 #include <linux/version.h>
72 #include <linux/module.h>
73 #include <linux/kernel.h>
74 #include <linux/sched.h>
75 #include <linux/types.h>
76 #include <linux/fcntl.h>
77 #include <linux/interrupt.h>
78 #include <linux/ioport.h>
79 #include <linux/in.h>
80 #include <linux/string.h>
81 #include <asm/system.h>
82 #include <asm/bitops.h>
83 #include <asm/uaccess.h>
84 #include <linux/init.h>
85 #include <linux/delay.h>
86 #include <linux/errno.h>
87 #include <linux/netdevice.h>
88 #include <linux/hdlcdrv.h>
89 #include <linux/baycom.h>
90 #include <linux/parport.h>
91
92 /* --------------------------------------------------------------------- */
93
94 #define BAYCOM_DEBUG
95
96 /*
97 * modem options; bit mask
98 */
99 #define BAYCOM_OPTIONS_SOFTDCD 1
100
101 /* --------------------------------------------------------------------- */
102
103 static const char bc_drvname[] = "baycom_par";
104 static const char bc_drvinfo[] = KERN_INFO "baycom_par: (C) 1996-2000 Thomas Sailer, HB9JNX/AE4WA\n"
105 KERN_INFO "baycom_par: version 0.9 compiled " __TIME__ " " __DATE__ "\n";
106
107 /* --------------------------------------------------------------------- */
108
109 #define NR_PORTS 4
110
111 static struct net_device baycom_device[NR_PORTS];
112
113 /* --------------------------------------------------------------------- */
114
115 #define PAR96_BURSTBITS 16
116 #define PAR96_BURST 4
117 #define PAR96_PTT 2
118 #define PAR96_TXBIT 1
119 #define PAR96_ACK 0x40
120 #define PAR96_RXBIT 0x20
121 #define PAR96_DCD 0x10
122 #define PAR97_POWER 0xf8
123
124 /* ---------------------------------------------------------------------- */
125 /*
126 * Information that need to be kept for each board.
127 */
128
129 struct baycom_state {
130 struct hdlcdrv_state hdrv;
131
132 struct pardevice *pdev;
133 unsigned int options;
134
135 struct modem_state {
136 short arb_divider;
137 unsigned char flags;
138 unsigned int shreg;
139 struct modem_state_par96 {
140 int dcd_count;
141 unsigned int dcd_shreg;
142 unsigned long descram;
143 unsigned long scram;
144 } par96;
145 } modem;
146
147 #ifdef BAYCOM_DEBUG
148 struct debug_vals {
149 unsigned long last_jiffies;
150 unsigned cur_intcnt;
151 unsigned last_intcnt;
152 int cur_pllcorr;
153 int last_pllcorr;
154 } debug_vals;
155 #endif /* BAYCOM_DEBUG */
156 };
157
158 /* --------------------------------------------------------------------- */
159
baycom_int_freq(struct baycom_state * bc)160 static void __inline__ baycom_int_freq(struct baycom_state *bc)
161 {
162 #ifdef BAYCOM_DEBUG
163 unsigned long cur_jiffies = jiffies;
164 /*
165 * measure the interrupt frequency
166 */
167 bc->debug_vals.cur_intcnt++;
168 if ((cur_jiffies - bc->debug_vals.last_jiffies) >= HZ) {
169 bc->debug_vals.last_jiffies = cur_jiffies;
170 bc->debug_vals.last_intcnt = bc->debug_vals.cur_intcnt;
171 bc->debug_vals.cur_intcnt = 0;
172 bc->debug_vals.last_pllcorr = bc->debug_vals.cur_pllcorr;
173 bc->debug_vals.cur_pllcorr = 0;
174 }
175 #endif /* BAYCOM_DEBUG */
176 }
177
178 /* --------------------------------------------------------------------- */
179 /*
180 * ===================== PAR96 specific routines =========================
181 */
182
183 #define PAR96_DESCRAM_TAP1 0x20000
184 #define PAR96_DESCRAM_TAP2 0x01000
185 #define PAR96_DESCRAM_TAP3 0x00001
186
187 #define PAR96_DESCRAM_TAPSH1 17
188 #define PAR96_DESCRAM_TAPSH2 12
189 #define PAR96_DESCRAM_TAPSH3 0
190
191 #define PAR96_SCRAM_TAP1 0x20000 /* X^17 */
192 #define PAR96_SCRAM_TAPN 0x00021 /* X^0+X^5 */
193
194 /* --------------------------------------------------------------------- */
195
par96_tx(struct net_device * dev,struct baycom_state * bc)196 static __inline__ void par96_tx(struct net_device *dev, struct baycom_state *bc)
197 {
198 int i;
199 unsigned int data = hdlcdrv_getbits(&bc->hdrv);
200 struct parport *pp = bc->pdev->port;
201
202 for(i = 0; i < PAR96_BURSTBITS; i++, data >>= 1) {
203 unsigned char val = PAR97_POWER;
204 bc->modem.par96.scram = ((bc->modem.par96.scram << 1) |
205 (bc->modem.par96.scram & 1));
206 if (!(data & 1))
207 bc->modem.par96.scram ^= 1;
208 if (bc->modem.par96.scram & (PAR96_SCRAM_TAP1 << 1))
209 bc->modem.par96.scram ^=
210 (PAR96_SCRAM_TAPN << 1);
211 if (bc->modem.par96.scram & (PAR96_SCRAM_TAP1 << 2))
212 val |= PAR96_TXBIT;
213 pp->ops->write_data(pp, val);
214 pp->ops->write_data(pp, val | PAR96_BURST);
215 }
216 }
217
218 /* --------------------------------------------------------------------- */
219
par96_rx(struct net_device * dev,struct baycom_state * bc)220 static __inline__ void par96_rx(struct net_device *dev, struct baycom_state *bc)
221 {
222 int i;
223 unsigned int data, mask, mask2, descx;
224 struct parport *pp = bc->pdev->port;
225
226 /*
227 * do receiver; differential decode and descramble on the fly
228 */
229 for(data = i = 0; i < PAR96_BURSTBITS; i++) {
230 bc->modem.par96.descram = (bc->modem.par96.descram << 1);
231 if (pp->ops->read_status(pp) & PAR96_RXBIT)
232 bc->modem.par96.descram |= 1;
233 descx = bc->modem.par96.descram ^
234 (bc->modem.par96.descram >> 1);
235 /* now the diff decoded data is inverted in descram */
236 pp->ops->write_data(pp, PAR97_POWER | PAR96_PTT);
237 descx ^= ((descx >> PAR96_DESCRAM_TAPSH1) ^
238 (descx >> PAR96_DESCRAM_TAPSH2));
239 data >>= 1;
240 if (!(descx & 1))
241 data |= 0x8000;
242 pp->ops->write_data(pp, PAR97_POWER | PAR96_PTT | PAR96_BURST);
243 }
244 hdlcdrv_putbits(&bc->hdrv, data);
245 /*
246 * do DCD algorithm
247 */
248 if (bc->options & BAYCOM_OPTIONS_SOFTDCD) {
249 bc->modem.par96.dcd_shreg = (bc->modem.par96.dcd_shreg >> 16)
250 | (data << 16);
251 /* search for flags and set the dcd counter appropriately */
252 for(mask = 0x1fe00, mask2 = 0xfc00, i = 0;
253 i < PAR96_BURSTBITS; i++, mask <<= 1, mask2 <<= 1)
254 if ((bc->modem.par96.dcd_shreg & mask) == mask2)
255 bc->modem.par96.dcd_count = HDLCDRV_MAXFLEN+4;
256 /* check for abort/noise sequences */
257 for(mask = 0x1fe00, mask2 = 0x1fe00, i = 0;
258 i < PAR96_BURSTBITS; i++, mask <<= 1, mask2 <<= 1)
259 if (((bc->modem.par96.dcd_shreg & mask) == mask2) &&
260 (bc->modem.par96.dcd_count >= 0))
261 bc->modem.par96.dcd_count -= HDLCDRV_MAXFLEN-10;
262 /* decrement and set the dcd variable */
263 if (bc->modem.par96.dcd_count >= 0)
264 bc->modem.par96.dcd_count -= 2;
265 hdlcdrv_setdcd(&bc->hdrv, bc->modem.par96.dcd_count > 0);
266 } else {
267 hdlcdrv_setdcd(&bc->hdrv, !!(pp->ops->read_status(pp) & PAR96_DCD));
268 }
269 }
270
271 /* --------------------------------------------------------------------- */
272
par96_interrupt(int irq,void * dev_id,struct pt_regs * regs)273 static void par96_interrupt(int irq, void *dev_id, struct pt_regs *regs)
274 {
275 struct net_device *dev = (struct net_device *)dev_id;
276 struct baycom_state *bc = (struct baycom_state *)dev->priv;
277
278 if (!dev || !bc || bc->hdrv.magic != HDLCDRV_MAGIC)
279 return;
280
281 baycom_int_freq(bc);
282 /*
283 * check if transmitter active
284 */
285 if (hdlcdrv_ptt(&bc->hdrv))
286 par96_tx(dev, bc);
287 else {
288 par96_rx(dev, bc);
289 if (--bc->modem.arb_divider <= 0) {
290 bc->modem.arb_divider = 6;
291 __sti();
292 hdlcdrv_arbitrate(dev, &bc->hdrv);
293 }
294 }
295 __sti();
296 hdlcdrv_transmitter(dev, &bc->hdrv);
297 hdlcdrv_receiver(dev, &bc->hdrv);
298 __cli();
299 }
300
301 /* --------------------------------------------------------------------- */
302
par96_wakeup(void * handle)303 static void par96_wakeup(void *handle)
304 {
305 struct net_device *dev = (struct net_device *)handle;
306 struct baycom_state *bc = (struct baycom_state *)dev->priv;
307
308 printk(KERN_DEBUG "baycom_par: %s: why am I being woken up?\n", dev->name);
309 if (!parport_claim(bc->pdev))
310 printk(KERN_DEBUG "baycom_par: %s: I'm broken.\n", dev->name);
311 }
312
313 /* --------------------------------------------------------------------- */
314
par96_open(struct net_device * dev)315 static int par96_open(struct net_device *dev)
316 {
317 struct baycom_state *bc = (struct baycom_state *)dev->priv;
318 struct parport *pp = parport_enumerate();
319
320 if (!dev || !bc)
321 return -ENXIO;
322 while (pp && pp->base != dev->base_addr)
323 pp = pp->next;
324 if (!pp) {
325 printk(KERN_ERR "baycom_par: parport at 0x%lx unknown\n", dev->base_addr);
326 return -ENXIO;
327 }
328 if (pp->irq < 0) {
329 printk(KERN_ERR "baycom_par: parport at 0x%lx has no irq\n", pp->base);
330 return -ENXIO;
331 }
332 if ((~pp->modes) & (PARPORT_MODE_PCSPP | PARPORT_MODE_SAFEININT)) {
333 printk(KERN_ERR "baycom_par: parport at 0x%lx cannot be used\n", pp->base);
334 return -ENXIO;
335 }
336 memset(&bc->modem, 0, sizeof(bc->modem));
337 bc->hdrv.par.bitrate = 9600;
338 if (!(bc->pdev = parport_register_device(pp, dev->name, NULL, par96_wakeup,
339 par96_interrupt, PARPORT_DEV_EXCL, dev))) {
340 printk(KERN_ERR "baycom_par: cannot register parport at 0x%lx\n", pp->base);
341 return -ENXIO;
342 }
343 if (parport_claim(bc->pdev)) {
344 printk(KERN_ERR "baycom_par: parport at 0x%lx busy\n", pp->base);
345 parport_unregister_device(bc->pdev);
346 return -EBUSY;
347 }
348 pp = bc->pdev->port;
349 dev->irq = pp->irq;
350 pp->ops->data_forward(pp);
351 bc->hdrv.par.bitrate = 9600;
352 pp->ops->write_data(pp, PAR96_PTT | PAR97_POWER); /* switch off PTT */
353 pp->ops->enable_irq(pp);
354 printk(KERN_INFO "%s: par96 at iobase 0x%lx irq %u options 0x%x\n",
355 bc_drvname, dev->base_addr, dev->irq, bc->options);
356 MOD_INC_USE_COUNT;
357 return 0;
358 }
359
360 /* --------------------------------------------------------------------- */
361
par96_close(struct net_device * dev)362 static int par96_close(struct net_device *dev)
363 {
364 struct baycom_state *bc = (struct baycom_state *)dev->priv;
365 struct parport *pp;
366
367 if (!dev || !bc)
368 return -EINVAL;
369 pp = bc->pdev->port;
370 /* disable interrupt */
371 pp->ops->disable_irq(pp);
372 /* switch off PTT */
373 pp->ops->write_data(pp, PAR96_PTT | PAR97_POWER);
374 parport_release(bc->pdev);
375 parport_unregister_device(bc->pdev);
376 printk(KERN_INFO "%s: close par96 at iobase 0x%lx irq %u\n",
377 bc_drvname, dev->base_addr, dev->irq);
378 MOD_DEC_USE_COUNT;
379 return 0;
380 }
381
382 /* --------------------------------------------------------------------- */
383 /*
384 * ===================== hdlcdrv driver interface =========================
385 */
386
387 static int baycom_ioctl(struct net_device *dev, struct ifreq *ifr,
388 struct hdlcdrv_ioctl *hi, int cmd);
389
390 /* --------------------------------------------------------------------- */
391
392 static struct hdlcdrv_ops par96_ops = {
393 bc_drvname,
394 bc_drvinfo,
395 par96_open,
396 par96_close,
397 baycom_ioctl
398 };
399
400 /* --------------------------------------------------------------------- */
401
baycom_setmode(struct baycom_state * bc,const char * modestr)402 static int baycom_setmode(struct baycom_state *bc, const char *modestr)
403 {
404 if (!strncmp(modestr, "picpar", 6))
405 bc->options = 0;
406 else if (!strncmp(modestr, "par96", 5))
407 bc->options = BAYCOM_OPTIONS_SOFTDCD;
408 else
409 bc->options = !!strchr(modestr, '*');
410 return 0;
411 }
412
413 /* --------------------------------------------------------------------- */
414
baycom_ioctl(struct net_device * dev,struct ifreq * ifr,struct hdlcdrv_ioctl * hi,int cmd)415 static int baycom_ioctl(struct net_device *dev, struct ifreq *ifr,
416 struct hdlcdrv_ioctl *hi, int cmd)
417 {
418 struct baycom_state *bc;
419 struct baycom_ioctl bi;
420 int cmd2;
421
422 if (!dev || !dev->priv ||
423 ((struct baycom_state *)dev->priv)->hdrv.magic != HDLCDRV_MAGIC) {
424 printk(KERN_ERR "bc_ioctl: invalid device struct\n");
425 return -EINVAL;
426 }
427 bc = (struct baycom_state *)dev->priv;
428
429 if (cmd != SIOCDEVPRIVATE)
430 return -ENOIOCTLCMD;
431 if (get_user(cmd2, (int *)ifr->ifr_data))
432 return -EFAULT;
433 switch (hi->cmd) {
434 default:
435 break;
436
437 case HDLCDRVCTL_GETMODE:
438 strcpy(hi->data.modename, bc->options ? "par96" : "picpar");
439 if (copy_to_user(ifr->ifr_data, hi, sizeof(struct hdlcdrv_ioctl)))
440 return -EFAULT;
441 return 0;
442
443 case HDLCDRVCTL_SETMODE:
444 if (netif_running(dev) || !capable(CAP_NET_ADMIN))
445 return -EACCES;
446 hi->data.modename[sizeof(hi->data.modename)-1] = '\0';
447 return baycom_setmode(bc, hi->data.modename);
448
449 case HDLCDRVCTL_MODELIST:
450 strcpy(hi->data.modename, "par96,picpar");
451 if (copy_to_user(ifr->ifr_data, hi, sizeof(struct hdlcdrv_ioctl)))
452 return -EFAULT;
453 return 0;
454
455 case HDLCDRVCTL_MODEMPARMASK:
456 return HDLCDRV_PARMASK_IOBASE;
457
458 }
459
460 if (copy_from_user(&bi, ifr->ifr_data, sizeof(bi)))
461 return -EFAULT;
462 switch (bi.cmd) {
463 default:
464 return -ENOIOCTLCMD;
465
466 #ifdef BAYCOM_DEBUG
467 case BAYCOMCTL_GETDEBUG:
468 bi.data.dbg.debug1 = bc->hdrv.ptt_keyed;
469 bi.data.dbg.debug2 = bc->debug_vals.last_intcnt;
470 bi.data.dbg.debug3 = bc->debug_vals.last_pllcorr;
471 break;
472 #endif /* BAYCOM_DEBUG */
473
474 }
475 if (copy_to_user(ifr->ifr_data, &bi, sizeof(bi)))
476 return -EFAULT;
477 return 0;
478
479 }
480
481 /* --------------------------------------------------------------------- */
482
483 /*
484 * command line settable parameters
485 */
486 static const char *mode[NR_PORTS] = { "picpar", };
487 static int iobase[NR_PORTS] = { 0x378, };
488
489 MODULE_PARM(mode, "1-" __MODULE_STRING(NR_PORTS) "s");
490 MODULE_PARM_DESC(mode, "baycom operating mode; eg. par96 or picpar");
491 MODULE_PARM(iobase, "1-" __MODULE_STRING(NR_PORTS) "i");
492 MODULE_PARM_DESC(iobase, "baycom io base address");
493
494 MODULE_AUTHOR("Thomas M. Sailer, sailer@ife.ee.ethz.ch, hb9jnx@hb9w.che.eu");
495 MODULE_DESCRIPTION("Baycom par96 and picpar amateur radio modem driver");
496 MODULE_LICENSE("GPL");
497
498 /* --------------------------------------------------------------------- */
499
init_baycompar(void)500 static int __init init_baycompar(void)
501 {
502 int i, j, found = 0;
503 char set_hw = 1;
504 struct baycom_state *bc;
505
506 printk(bc_drvinfo);
507 /*
508 * register net devices
509 */
510 for (i = 0; i < NR_PORTS; i++) {
511 struct net_device *dev = baycom_device+i;
512 char ifname[IFNAMSIZ];
513
514 sprintf(ifname, "bcp%d", i);
515 if (!mode[i])
516 set_hw = 0;
517 if (!set_hw)
518 iobase[i] = 0;
519 j = hdlcdrv_register_hdlcdrv(dev, &par96_ops, sizeof(struct baycom_state),
520 ifname, iobase[i], 0, 0);
521 if (!j) {
522 bc = (struct baycom_state *)dev->priv;
523 if (set_hw && baycom_setmode(bc, mode[i]))
524 set_hw = 0;
525 found++;
526 } else {
527 printk(KERN_WARNING "%s: cannot register net device\n",
528 bc_drvname);
529 }
530 }
531 if (!found)
532 return -ENXIO;
533 return 0;
534 }
535
cleanup_baycompar(void)536 static void __exit cleanup_baycompar(void)
537 {
538 int i;
539
540 for(i = 0; i < NR_PORTS; i++) {
541 struct net_device *dev = baycom_device+i;
542 struct baycom_state *bc = (struct baycom_state *)dev->priv;
543
544 if (bc) {
545 if (bc->hdrv.magic != HDLCDRV_MAGIC)
546 printk(KERN_ERR "baycom: invalid magic in "
547 "cleanup_module\n");
548 else
549 hdlcdrv_unregister_hdlcdrv(dev);
550 }
551 }
552 }
553
554 module_init(init_baycompar);
555 module_exit(cleanup_baycompar);
556
557 /* --------------------------------------------------------------------- */
558
559 #ifndef MODULE
560
561 /*
562 * format: baycom_par=io,mode
563 * mode: par96,picpar
564 */
565
baycom_par_setup(char * str)566 static int __init baycom_par_setup(char *str)
567 {
568 static unsigned nr_dev;
569 int ints[2];
570
571 if (nr_dev >= NR_PORTS)
572 return 0;
573 str = get_options(str, 2, ints);
574 if (ints[0] < 1)
575 return 0;
576 mode[nr_dev] = str;
577 iobase[nr_dev] = ints[1];
578 nr_dev++;
579 return 1;
580 }
581
582 __setup("baycom_par=", baycom_par_setup);
583
584 #endif /* MODULE */
585 /* --------------------------------------------------------------------- */
586