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 This modem is no longer available (at least 37 * from Baycom) and has been replaced by the PICPAR modem (see below). 38 * You may however still build one from the schematics published in 39 * cq-DL :-). 40 * 41 * picpar: This is a redesign of the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 <linux/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 inline void 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 pardev_cb par_cb; 315 struct parport *pp; 316 int i; 317 318 if (!dev || !bc) 319 return -ENXIO; 320 pp = parport_find_base(dev->base_addr); 321 if (!pp) { 322 printk(KERN_ERR "baycom_par: parport at 0x%lx unknown\n", dev->base_addr); 323 return -ENXIO; 324 } 325 if (pp->irq < 0) { 326 printk(KERN_ERR "baycom_par: parport at 0x%lx has no irq\n", pp->base); 327 parport_put_port(pp); 328 return -ENXIO; 329 } 330 if ((~pp->modes) & (PARPORT_MODE_PCSPP | PARPORT_MODE_SAFEININT)) { 331 printk(KERN_ERR "baycom_par: parport at 0x%lx cannot be used\n", pp->base); 332 parport_put_port(pp); 333 return -ENXIO; 334 } 335 memset(&bc->modem, 0, sizeof(bc->modem)); 336 bc->hdrv.par.bitrate = 9600; 337 memset(&par_cb, 0, sizeof(par_cb)); 338 par_cb.wakeup = par96_wakeup; 339 par_cb.irq_func = par96_interrupt; 340 par_cb.private = (void *)dev; 341 par_cb.flags = PARPORT_DEV_EXCL; 342 for (i = 0; i < NR_PORTS; i++) 343 if (baycom_device[i] == dev) 344 break; 345 346 if (i == NR_PORTS) { 347 pr_err("%s: no device found\n", bc_drvname); 348 parport_put_port(pp); 349 return -ENODEV; 350 } 351 bc->pdev = parport_register_dev_model(pp, dev->name, &par_cb, i); 352 parport_put_port(pp); 353 if (!bc->pdev) { 354 printk(KERN_ERR "baycom_par: cannot register parport at 0x%lx\n", dev->base_addr); 355 return -ENXIO; 356 } 357 if (parport_claim(bc->pdev)) { 358 printk(KERN_ERR "baycom_par: parport at 0x%lx busy\n", pp->base); 359 parport_unregister_device(bc->pdev); 360 return -EBUSY; 361 } 362 pp = bc->pdev->port; 363 dev->irq = pp->irq; 364 pp->ops->data_forward(pp); 365 bc->hdrv.par.bitrate = 9600; 366 pp->ops->write_data(pp, PAR96_PTT | PAR97_POWER); /* switch off PTT */ 367 pp->ops->enable_irq(pp); 368 printk(KERN_INFO "%s: par96 at iobase 0x%lx irq %u options 0x%x\n", 369 bc_drvname, dev->base_addr, dev->irq, bc->options); 370 return 0; 371 } 372 373 /* --------------------------------------------------------------------- */ 374 375 static int par96_close(struct net_device *dev) 376 { 377 struct baycom_state *bc = netdev_priv(dev); 378 struct parport *pp; 379 380 if (!dev || !bc) 381 return -EINVAL; 382 pp = bc->pdev->port; 383 /* disable interrupt */ 384 pp->ops->disable_irq(pp); 385 /* switch off PTT */ 386 pp->ops->write_data(pp, PAR96_PTT | PAR97_POWER); 387 parport_release(bc->pdev); 388 parport_unregister_device(bc->pdev); 389 printk(KERN_INFO "%s: close par96 at iobase 0x%lx irq %u\n", 390 bc_drvname, dev->base_addr, dev->irq); 391 return 0; 392 } 393 394 /* --------------------------------------------------------------------- */ 395 /* 396 * ===================== hdlcdrv driver interface ========================= 397 */ 398 399 static int baycom_ioctl(struct net_device *dev, struct ifreq *ifr, 400 struct hdlcdrv_ioctl *hi, int cmd); 401 402 /* --------------------------------------------------------------------- */ 403 404 static const struct hdlcdrv_ops par96_ops = { 405 .drvname = bc_drvname, 406 .drvinfo = bc_drvinfo, 407 .open = par96_open, 408 .close = par96_close, 409 .ioctl = baycom_ioctl 410 }; 411 412 /* --------------------------------------------------------------------- */ 413 414 static int baycom_setmode(struct baycom_state *bc, const char *modestr) 415 { 416 if (!strncmp(modestr, "picpar", 6)) 417 bc->options = 0; 418 else if (!strncmp(modestr, "par96", 5)) 419 bc->options = BAYCOM_OPTIONS_SOFTDCD; 420 else 421 bc->options = !!strchr(modestr, '*'); 422 return 0; 423 } 424 425 /* --------------------------------------------------------------------- */ 426 427 static int baycom_ioctl(struct net_device *dev, struct ifreq *ifr, 428 struct hdlcdrv_ioctl *hi, int cmd) 429 { 430 struct baycom_state *bc; 431 struct baycom_ioctl bi; 432 433 if (!dev) 434 return -EINVAL; 435 436 bc = netdev_priv(dev); 437 BUG_ON(bc->hdrv.magic != HDLCDRV_MAGIC); 438 439 if (cmd != SIOCDEVPRIVATE) 440 return -ENOIOCTLCMD; 441 switch (hi->cmd) { 442 default: 443 break; 444 445 case HDLCDRVCTL_GETMODE: 446 strcpy(hi->data.modename, bc->options ? "par96" : "picpar"); 447 if (copy_to_user(ifr->ifr_data, hi, sizeof(struct hdlcdrv_ioctl))) 448 return -EFAULT; 449 return 0; 450 451 case HDLCDRVCTL_SETMODE: 452 if (netif_running(dev) || !capable(CAP_NET_ADMIN)) 453 return -EACCES; 454 hi->data.modename[sizeof(hi->data.modename)-1] = '\0'; 455 return baycom_setmode(bc, hi->data.modename); 456 457 case HDLCDRVCTL_MODELIST: 458 strcpy(hi->data.modename, "par96,picpar"); 459 if (copy_to_user(ifr->ifr_data, hi, sizeof(struct hdlcdrv_ioctl))) 460 return -EFAULT; 461 return 0; 462 463 case HDLCDRVCTL_MODEMPARMASK: 464 return HDLCDRV_PARMASK_IOBASE; 465 466 } 467 468 if (copy_from_user(&bi, ifr->ifr_data, sizeof(bi))) 469 return -EFAULT; 470 switch (bi.cmd) { 471 default: 472 return -ENOIOCTLCMD; 473 474 #ifdef BAYCOM_DEBUG 475 case BAYCOMCTL_GETDEBUG: 476 bi.data.dbg.debug1 = bc->hdrv.ptt_keyed; 477 bi.data.dbg.debug2 = bc->debug_vals.last_intcnt; 478 bi.data.dbg.debug3 = bc->debug_vals.last_pllcorr; 479 break; 480 #endif /* BAYCOM_DEBUG */ 481 482 } 483 if (copy_to_user(ifr->ifr_data, &bi, sizeof(bi))) 484 return -EFAULT; 485 return 0; 486 487 } 488 489 /* --------------------------------------------------------------------- */ 490 491 /* 492 * command line settable parameters 493 */ 494 static char *mode[NR_PORTS] = { "picpar", }; 495 static int iobase[NR_PORTS] = { 0x378, }; 496 497 module_param_array(mode, charp, NULL, 0); 498 MODULE_PARM_DESC(mode, "baycom operating mode; eg. par96 or picpar"); 499 module_param_hw_array(iobase, int, ioport, NULL, 0); 500 MODULE_PARM_DESC(iobase, "baycom io base address"); 501 502 MODULE_AUTHOR("Thomas M. Sailer, sailer@ife.ee.ethz.ch, hb9jnx@hb9w.che.eu"); 503 MODULE_DESCRIPTION("Baycom par96 and picpar amateur radio modem driver"); 504 MODULE_LICENSE("GPL"); 505 506 /* --------------------------------------------------------------------- */ 507 508 static int baycom_par_probe(struct pardevice *par_dev) 509 { 510 struct device_driver *drv = par_dev->dev.driver; 511 int len = strlen(drv->name); 512 513 if (strncmp(par_dev->name, drv->name, len)) 514 return -ENODEV; 515 516 return 0; 517 } 518 519 static struct parport_driver baycom_par_driver = { 520 .name = "bcp", 521 .probe = baycom_par_probe, 522 .devmodel = true, 523 }; 524 525 static int __init init_baycompar(void) 526 { 527 int i, found = 0, ret; 528 char set_hw = 1; 529 530 printk(bc_drvinfo); 531 532 ret = parport_register_driver(&baycom_par_driver); 533 if (ret) 534 return ret; 535 536 /* 537 * register net devices 538 */ 539 for (i = 0; i < NR_PORTS; i++) { 540 struct net_device *dev; 541 struct baycom_state *bc; 542 char ifname[IFNAMSIZ]; 543 544 sprintf(ifname, "bcp%d", i); 545 546 if (!mode[i]) 547 set_hw = 0; 548 if (!set_hw) 549 iobase[i] = 0; 550 551 dev = hdlcdrv_register(&par96_ops, 552 sizeof(struct baycom_state), 553 ifname, iobase[i], 0, 0); 554 if (IS_ERR(dev)) 555 break; 556 557 bc = netdev_priv(dev); 558 if (set_hw && baycom_setmode(bc, mode[i])) 559 set_hw = 0; 560 found++; 561 baycom_device[i] = dev; 562 } 563 564 if (!found) { 565 parport_unregister_driver(&baycom_par_driver); 566 return -ENXIO; 567 } 568 return 0; 569 } 570 571 static void __exit cleanup_baycompar(void) 572 { 573 int i; 574 575 for(i = 0; i < NR_PORTS; i++) { 576 struct net_device *dev = baycom_device[i]; 577 578 if (dev) 579 hdlcdrv_unregister(dev); 580 } 581 parport_unregister_driver(&baycom_par_driver); 582 } 583 584 module_init(init_baycompar); 585 module_exit(cleanup_baycompar); 586 587 /* --------------------------------------------------------------------- */ 588 589 #ifndef MODULE 590 591 /* 592 * format: baycom_par=io,mode 593 * mode: par96,picpar 594 */ 595 596 static int __init baycom_par_setup(char *str) 597 { 598 static unsigned nr_dev; 599 int ints[2]; 600 601 if (nr_dev >= NR_PORTS) 602 return 0; 603 str = get_options(str, 2, ints); 604 if (ints[0] < 1) 605 return 0; 606 mode[nr_dev] = str; 607 iobase[nr_dev] = ints[1]; 608 nr_dev++; 609 return 1; 610 } 611 612 __setup("baycom_par=", baycom_par_setup); 613 614 #endif /* MODULE */ 615 /* --------------------------------------------------------------------- */ 616