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 This modem is no longer available (at least 37 * from Baycom) and has been replaced by the PICPAR modem (see below). 38 * You may however still build one from the schematics published in 39 * cq-DL :-). 40 * 41 * picpar: This is a redesign of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