Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame^] | 1 | /* r3964 linediscipline for linux |
| 2 | * |
| 3 | * ----------------------------------------------------------- |
| 4 | * Copyright by |
| 5 | * Philips Automation Projects |
| 6 | * Kassel (Germany) |
| 7 | * http://www.pap-philips.de |
| 8 | * ----------------------------------------------------------- |
| 9 | * This software may be used and distributed according to the terms of |
| 10 | * the GNU General Public License, incorporated herein by reference. |
| 11 | * |
| 12 | * Author: |
| 13 | * L. Haag |
| 14 | * |
| 15 | * $Log: n_r3964.c,v $ |
| 16 | * Revision 1.10 2001/03/18 13:02:24 dwmw2 |
| 17 | * Fix timer usage, use spinlocks properly. |
| 18 | * |
| 19 | * Revision 1.9 2001/03/18 12:52:14 dwmw2 |
| 20 | * Merge changes in 2.4.2 |
| 21 | * |
| 22 | * Revision 1.8 2000/03/23 14:14:54 dwmw2 |
| 23 | * Fix race in sleeping in r3964_read() |
| 24 | * |
| 25 | * Revision 1.7 1999/28/08 11:41:50 dwmw2 |
| 26 | * Port to 2.3 kernel |
| 27 | * |
| 28 | * Revision 1.6 1998/09/30 00:40:40 dwmw2 |
| 29 | * Fixed compilation on 2.0.x kernels |
| 30 | * Updated to newly registered tty-ldisc number 9 |
| 31 | * |
| 32 | * Revision 1.5 1998/09/04 21:57:36 dwmw2 |
| 33 | * Signal handling bug fixes, port to 2.1.x. |
| 34 | * |
| 35 | * Revision 1.4 1998/04/02 20:26:59 lhaag |
| 36 | * select, blocking, ... |
| 37 | * |
| 38 | * Revision 1.3 1998/02/12 18:58:43 root |
| 39 | * fixed some memory leaks |
| 40 | * calculation of checksum characters |
| 41 | * |
| 42 | * Revision 1.2 1998/02/07 13:03:34 root |
| 43 | * ioctl read_telegram |
| 44 | * |
| 45 | * Revision 1.1 1998/02/06 19:21:03 root |
| 46 | * Initial revision |
| 47 | * |
| 48 | * |
| 49 | */ |
| 50 | |
| 51 | #include <linux/module.h> |
| 52 | #include <linux/kernel.h> |
| 53 | #include <linux/sched.h> |
| 54 | #include <linux/types.h> |
| 55 | #include <linux/fcntl.h> |
| 56 | #include <linux/interrupt.h> |
| 57 | #include <linux/ptrace.h> |
| 58 | #include <linux/ioport.h> |
| 59 | #include <linux/in.h> |
| 60 | #include <linux/slab.h> |
| 61 | #include <linux/tty.h> |
| 62 | #include <linux/errno.h> |
| 63 | #include <linux/string.h> /* used in new tty drivers */ |
| 64 | #include <linux/signal.h> /* used in new tty drivers */ |
| 65 | #include <linux/ioctl.h> |
| 66 | #include <linux/n_r3964.h> |
| 67 | #include <linux/poll.h> |
| 68 | #include <linux/init.h> |
| 69 | #include <asm/uaccess.h> |
| 70 | |
| 71 | |
| 72 | //#define DEBUG_QUEUE |
| 73 | |
| 74 | /* Log successful handshake and protocol operations */ |
| 75 | //#define DEBUG_PROTO_S |
| 76 | |
| 77 | /* Log handshake and protocol errors: */ |
| 78 | //#define DEBUG_PROTO_E |
| 79 | |
| 80 | /* Log Linediscipline operations (open, close, read, write...): */ |
| 81 | //#define DEBUG_LDISC |
| 82 | |
| 83 | /* Log module and memory operations (init, cleanup; kmalloc, kfree): */ |
| 84 | //#define DEBUG_MODUL |
| 85 | |
| 86 | /* Macro helpers for debug output: */ |
| 87 | #define TRACE(format, args...) printk("r3964: " format "\n" , ## args); |
| 88 | |
| 89 | #ifdef DEBUG_MODUL |
| 90 | #define TRACE_M(format, args...) printk("r3964: " format "\n" , ## args); |
| 91 | #else |
| 92 | #define TRACE_M(fmt, arg...) /**/ |
| 93 | #endif |
| 94 | |
| 95 | #ifdef DEBUG_PROTO_S |
| 96 | #define TRACE_PS(format, args...) printk("r3964: " format "\n" , ## args); |
| 97 | #else |
| 98 | #define TRACE_PS(fmt, arg...) /**/ |
| 99 | #endif |
| 100 | |
| 101 | #ifdef DEBUG_PROTO_E |
| 102 | #define TRACE_PE(format, args...) printk("r3964: " format "\n" , ## args); |
| 103 | #else |
| 104 | #define TRACE_PE(fmt, arg...) /**/ |
| 105 | #endif |
| 106 | |
| 107 | #ifdef DEBUG_LDISC |
| 108 | #define TRACE_L(format, args...) printk("r3964: " format "\n" , ## args); |
| 109 | #else |
| 110 | #define TRACE_L(fmt, arg...) /**/ |
| 111 | #endif |
| 112 | |
| 113 | #ifdef DEBUG_QUEUE |
| 114 | #define TRACE_Q(format, args...) printk("r3964: " format "\n" , ## args); |
| 115 | #else |
| 116 | #define TRACE_Q(fmt, arg...) /**/ |
| 117 | #endif |
| 118 | |
| 119 | static void add_tx_queue(struct r3964_info *, struct r3964_block_header *); |
| 120 | static void remove_from_tx_queue(struct r3964_info *pInfo, int error_code); |
| 121 | static void put_char(struct r3964_info *pInfo, unsigned char ch); |
| 122 | static void trigger_transmit(struct r3964_info *pInfo); |
| 123 | static void retry_transmit(struct r3964_info *pInfo); |
| 124 | static void transmit_block(struct r3964_info *pInfo); |
| 125 | static void receive_char(struct r3964_info *pInfo, const unsigned char c); |
| 126 | static void receive_error(struct r3964_info *pInfo, const char flag); |
| 127 | static void on_timeout(unsigned long priv); |
| 128 | static int enable_signals(struct r3964_info *pInfo, pid_t pid, int arg); |
| 129 | static int read_telegram(struct r3964_info *pInfo, pid_t pid, unsigned char __user *buf); |
| 130 | static void add_msg(struct r3964_client_info *pClient, int msg_id, int arg, |
| 131 | int error_code, struct r3964_block_header *pBlock); |
| 132 | static struct r3964_message* remove_msg(struct r3964_info *pInfo, |
| 133 | struct r3964_client_info *pClient); |
| 134 | static void remove_client_block(struct r3964_info *pInfo, |
| 135 | struct r3964_client_info *pClient); |
| 136 | |
| 137 | static int r3964_open(struct tty_struct *tty); |
| 138 | static void r3964_close(struct tty_struct *tty); |
| 139 | static ssize_t r3964_read(struct tty_struct *tty, struct file *file, |
| 140 | unsigned char __user *buf, size_t nr); |
| 141 | static ssize_t r3964_write(struct tty_struct * tty, struct file * file, |
| 142 | const unsigned char * buf, size_t nr); |
| 143 | static int r3964_ioctl(struct tty_struct * tty, struct file * file, |
| 144 | unsigned int cmd, unsigned long arg); |
| 145 | static void r3964_set_termios(struct tty_struct *tty, struct termios * old); |
| 146 | static unsigned int r3964_poll(struct tty_struct * tty, struct file * file, |
| 147 | struct poll_table_struct *wait); |
| 148 | static void r3964_receive_buf(struct tty_struct *tty, const unsigned char *cp, |
| 149 | char *fp, int count); |
| 150 | static int r3964_receive_room(struct tty_struct *tty); |
| 151 | |
| 152 | static struct tty_ldisc tty_ldisc_N_R3964 = { |
| 153 | .owner = THIS_MODULE, |
| 154 | .magic = TTY_LDISC_MAGIC, |
| 155 | .name = "R3964", |
| 156 | .open = r3964_open, |
| 157 | .close = r3964_close, |
| 158 | .read = r3964_read, |
| 159 | .write = r3964_write, |
| 160 | .ioctl = r3964_ioctl, |
| 161 | .set_termios = r3964_set_termios, |
| 162 | .poll = r3964_poll, |
| 163 | .receive_buf = r3964_receive_buf, |
| 164 | .receive_room = r3964_receive_room, |
| 165 | }; |
| 166 | |
| 167 | |
| 168 | |
| 169 | static void dump_block(const unsigned char *block, unsigned int length) |
| 170 | { |
| 171 | unsigned int i,j; |
| 172 | char linebuf[16*3+1]; |
| 173 | |
| 174 | for(i=0;i<length;i+=16) |
| 175 | { |
| 176 | for(j=0;(j<16) && (j+i<length);j++) |
| 177 | { |
| 178 | sprintf(linebuf+3*j,"%02x ",block[i+j]); |
| 179 | } |
| 180 | linebuf[3*j]='\0'; |
| 181 | TRACE_PS("%s",linebuf); |
| 182 | } |
| 183 | } |
| 184 | |
| 185 | |
| 186 | |
| 187 | |
| 188 | /************************************************************* |
| 189 | * Driver initialisation |
| 190 | *************************************************************/ |
| 191 | |
| 192 | |
| 193 | /************************************************************* |
| 194 | * Module support routines |
| 195 | *************************************************************/ |
| 196 | |
| 197 | static void __exit r3964_exit(void) |
| 198 | { |
| 199 | int status; |
| 200 | |
| 201 | TRACE_M ("cleanup_module()"); |
| 202 | |
| 203 | status=tty_register_ldisc(N_R3964, NULL); |
| 204 | |
| 205 | if(status!=0) |
| 206 | { |
| 207 | printk(KERN_ERR "r3964: error unregistering linediscipline: %d\n", status); |
| 208 | } |
| 209 | else |
| 210 | { |
| 211 | TRACE_L("linediscipline successfully unregistered"); |
| 212 | } |
| 213 | |
| 214 | } |
| 215 | |
| 216 | static int __init r3964_init(void) |
| 217 | { |
| 218 | int status; |
| 219 | |
| 220 | printk ("r3964: Philips r3964 Driver $Revision: 1.10 $\n"); |
| 221 | |
| 222 | /* |
| 223 | * Register the tty line discipline |
| 224 | */ |
| 225 | |
| 226 | status = tty_register_ldisc (N_R3964, &tty_ldisc_N_R3964); |
| 227 | if (status == 0) |
| 228 | { |
| 229 | TRACE_L("line discipline %d registered", N_R3964); |
| 230 | TRACE_L("flags=%x num=%x", tty_ldisc_N_R3964.flags, |
| 231 | tty_ldisc_N_R3964.num); |
| 232 | TRACE_L("open=%x", (int)tty_ldisc_N_R3964.open); |
| 233 | TRACE_L("tty_ldisc_N_R3964 = %x", (int)&tty_ldisc_N_R3964); |
| 234 | } |
| 235 | else |
| 236 | { |
| 237 | printk (KERN_ERR "r3964: error registering line discipline: %d\n", status); |
| 238 | } |
| 239 | return status; |
| 240 | } |
| 241 | |
| 242 | module_init(r3964_init); |
| 243 | module_exit(r3964_exit); |
| 244 | |
| 245 | |
| 246 | /************************************************************* |
| 247 | * Protocol implementation routines |
| 248 | *************************************************************/ |
| 249 | |
| 250 | static void add_tx_queue(struct r3964_info *pInfo, struct r3964_block_header *pHeader) |
| 251 | { |
| 252 | unsigned long flags; |
| 253 | |
| 254 | spin_lock_irqsave(&pInfo->lock, flags); |
| 255 | |
| 256 | pHeader->next = NULL; |
| 257 | |
| 258 | if(pInfo->tx_last == NULL) |
| 259 | { |
| 260 | pInfo->tx_first = pInfo->tx_last = pHeader; |
| 261 | } |
| 262 | else |
| 263 | { |
| 264 | pInfo->tx_last->next = pHeader; |
| 265 | pInfo->tx_last = pHeader; |
| 266 | } |
| 267 | |
| 268 | spin_unlock_irqrestore(&pInfo->lock, flags); |
| 269 | |
| 270 | TRACE_Q("add_tx_queue %x, length %d, tx_first = %x", |
| 271 | (int)pHeader, pHeader->length, (int)pInfo->tx_first ); |
| 272 | } |
| 273 | |
| 274 | static void remove_from_tx_queue(struct r3964_info *pInfo, int error_code) |
| 275 | { |
| 276 | struct r3964_block_header *pHeader; |
| 277 | unsigned long flags; |
| 278 | #ifdef DEBUG_QUEUE |
| 279 | struct r3964_block_header *pDump; |
| 280 | #endif |
| 281 | |
| 282 | pHeader = pInfo->tx_first; |
| 283 | |
| 284 | if(pHeader==NULL) |
| 285 | return; |
| 286 | |
| 287 | #ifdef DEBUG_QUEUE |
| 288 | printk("r3964: remove_from_tx_queue: %x, length %d - ", |
| 289 | (int)pHeader, (int)pHeader->length ); |
| 290 | for(pDump=pHeader;pDump;pDump=pDump->next) |
| 291 | printk("%x ", (int)pDump); |
| 292 | printk("\n"); |
| 293 | #endif |
| 294 | |
| 295 | |
| 296 | if(pHeader->owner) |
| 297 | { |
| 298 | if(error_code) |
| 299 | { |
| 300 | add_msg(pHeader->owner, R3964_MSG_ACK, 0, |
| 301 | error_code, NULL); |
| 302 | } |
| 303 | else |
| 304 | { |
| 305 | add_msg(pHeader->owner, R3964_MSG_ACK, pHeader->length, |
| 306 | error_code, NULL); |
| 307 | } |
| 308 | wake_up_interruptible (&pInfo->read_wait); |
| 309 | } |
| 310 | |
| 311 | spin_lock_irqsave(&pInfo->lock, flags); |
| 312 | |
| 313 | pInfo->tx_first = pHeader->next; |
| 314 | if(pInfo->tx_first==NULL) |
| 315 | { |
| 316 | pInfo->tx_last = NULL; |
| 317 | } |
| 318 | |
| 319 | spin_unlock_irqrestore(&pInfo->lock, flags); |
| 320 | |
| 321 | kfree(pHeader); |
| 322 | TRACE_M("remove_from_tx_queue - kfree %x",(int)pHeader); |
| 323 | |
| 324 | TRACE_Q("remove_from_tx_queue: tx_first = %x, tx_last = %x", |
| 325 | (int)pInfo->tx_first, (int)pInfo->tx_last ); |
| 326 | } |
| 327 | |
| 328 | static void add_rx_queue(struct r3964_info *pInfo, struct r3964_block_header *pHeader) |
| 329 | { |
| 330 | unsigned long flags; |
| 331 | |
| 332 | spin_lock_irqsave(&pInfo->lock, flags); |
| 333 | |
| 334 | pHeader->next = NULL; |
| 335 | |
| 336 | if(pInfo->rx_last == NULL) |
| 337 | { |
| 338 | pInfo->rx_first = pInfo->rx_last = pHeader; |
| 339 | } |
| 340 | else |
| 341 | { |
| 342 | pInfo->rx_last->next = pHeader; |
| 343 | pInfo->rx_last = pHeader; |
| 344 | } |
| 345 | pInfo->blocks_in_rx_queue++; |
| 346 | |
| 347 | spin_unlock_irqrestore(&pInfo->lock, flags); |
| 348 | |
| 349 | TRACE_Q("add_rx_queue: %x, length = %d, rx_first = %x, count = %d", |
| 350 | (int)pHeader, pHeader->length, |
| 351 | (int)pInfo->rx_first, pInfo->blocks_in_rx_queue); |
| 352 | } |
| 353 | |
| 354 | static void remove_from_rx_queue(struct r3964_info *pInfo, |
| 355 | struct r3964_block_header *pHeader) |
| 356 | { |
| 357 | unsigned long flags; |
| 358 | struct r3964_block_header *pFind; |
| 359 | |
| 360 | if(pHeader==NULL) |
| 361 | return; |
| 362 | |
| 363 | TRACE_Q("remove_from_rx_queue: rx_first = %x, rx_last = %x, count = %d", |
| 364 | (int)pInfo->rx_first, (int)pInfo->rx_last, pInfo->blocks_in_rx_queue ); |
| 365 | TRACE_Q("remove_from_rx_queue: %x, length %d", |
| 366 | (int)pHeader, (int)pHeader->length ); |
| 367 | |
| 368 | spin_lock_irqsave(&pInfo->lock, flags); |
| 369 | |
| 370 | if(pInfo->rx_first == pHeader) |
| 371 | { |
| 372 | /* Remove the first block in the linked list: */ |
| 373 | pInfo->rx_first = pHeader->next; |
| 374 | |
| 375 | if(pInfo->rx_first==NULL) |
| 376 | { |
| 377 | pInfo->rx_last = NULL; |
| 378 | } |
| 379 | pInfo->blocks_in_rx_queue--; |
| 380 | } |
| 381 | else |
| 382 | { |
| 383 | /* Find block to remove: */ |
| 384 | for(pFind=pInfo->rx_first; pFind; pFind=pFind->next) |
| 385 | { |
| 386 | if(pFind->next == pHeader) |
| 387 | { |
| 388 | /* Got it. */ |
| 389 | pFind->next = pHeader->next; |
| 390 | pInfo->blocks_in_rx_queue--; |
| 391 | if(pFind->next==NULL) |
| 392 | { |
| 393 | /* Oh, removed the last one! */ |
| 394 | pInfo->rx_last = pFind; |
| 395 | } |
| 396 | break; |
| 397 | } |
| 398 | } |
| 399 | } |
| 400 | |
| 401 | spin_unlock_irqrestore(&pInfo->lock, flags); |
| 402 | |
| 403 | kfree(pHeader); |
| 404 | TRACE_M("remove_from_rx_queue - kfree %x",(int)pHeader); |
| 405 | |
| 406 | TRACE_Q("remove_from_rx_queue: rx_first = %x, rx_last = %x, count = %d", |
| 407 | (int)pInfo->rx_first, (int)pInfo->rx_last, pInfo->blocks_in_rx_queue ); |
| 408 | } |
| 409 | |
| 410 | static void put_char(struct r3964_info *pInfo, unsigned char ch) |
| 411 | { |
| 412 | struct tty_struct *tty = pInfo->tty; |
| 413 | |
| 414 | if(tty==NULL) |
| 415 | return; |
| 416 | |
| 417 | if(tty->driver->put_char) |
| 418 | { |
| 419 | tty->driver->put_char(tty, ch); |
| 420 | } |
| 421 | pInfo->bcc ^= ch; |
| 422 | } |
| 423 | |
| 424 | static void flush(struct r3964_info *pInfo) |
| 425 | { |
| 426 | struct tty_struct *tty = pInfo->tty; |
| 427 | |
| 428 | if(tty==NULL) |
| 429 | return; |
| 430 | |
| 431 | if(tty->driver->flush_chars) |
| 432 | { |
| 433 | tty->driver->flush_chars(tty); |
| 434 | } |
| 435 | } |
| 436 | |
| 437 | static void trigger_transmit(struct r3964_info *pInfo) |
| 438 | { |
| 439 | unsigned long flags; |
| 440 | |
| 441 | |
| 442 | spin_lock_irqsave(&pInfo->lock, flags); |
| 443 | |
| 444 | if((pInfo->state == R3964_IDLE) && (pInfo->tx_first!=NULL)) |
| 445 | { |
| 446 | pInfo->state = R3964_TX_REQUEST; |
| 447 | pInfo->nRetry=0; |
| 448 | pInfo->flags &= ~R3964_ERROR; |
| 449 | mod_timer(&pInfo->tmr, jiffies + R3964_TO_QVZ); |
| 450 | |
| 451 | spin_unlock_irqrestore(&pInfo->lock, flags); |
| 452 | |
| 453 | TRACE_PS("trigger_transmit - sent STX"); |
| 454 | |
| 455 | put_char(pInfo, STX); |
| 456 | flush(pInfo); |
| 457 | |
| 458 | pInfo->bcc = 0; |
| 459 | } |
| 460 | else |
| 461 | { |
| 462 | spin_unlock_irqrestore(&pInfo->lock, flags); |
| 463 | } |
| 464 | } |
| 465 | |
| 466 | static void retry_transmit(struct r3964_info *pInfo) |
| 467 | { |
| 468 | if(pInfo->nRetry<R3964_MAX_RETRIES) |
| 469 | { |
| 470 | TRACE_PE("transmission failed. Retry #%d", |
| 471 | pInfo->nRetry); |
| 472 | pInfo->bcc = 0; |
| 473 | put_char(pInfo, STX); |
| 474 | flush(pInfo); |
| 475 | pInfo->state = R3964_TX_REQUEST; |
| 476 | pInfo->nRetry++; |
| 477 | mod_timer(&pInfo->tmr, jiffies + R3964_TO_QVZ); |
| 478 | } |
| 479 | else |
| 480 | { |
| 481 | TRACE_PE("transmission failed after %d retries", |
| 482 | R3964_MAX_RETRIES); |
| 483 | |
| 484 | remove_from_tx_queue(pInfo, R3964_TX_FAIL); |
| 485 | |
| 486 | put_char(pInfo, NAK); |
| 487 | flush(pInfo); |
| 488 | pInfo->state = R3964_IDLE; |
| 489 | |
| 490 | trigger_transmit(pInfo); |
| 491 | } |
| 492 | } |
| 493 | |
| 494 | |
| 495 | static void transmit_block(struct r3964_info *pInfo) |
| 496 | { |
| 497 | struct tty_struct *tty = pInfo->tty; |
| 498 | struct r3964_block_header *pBlock = pInfo->tx_first; |
| 499 | int room=0; |
| 500 | |
| 501 | if((tty==NULL) || (pBlock==NULL)) |
| 502 | { |
| 503 | return; |
| 504 | } |
| 505 | |
| 506 | if(tty->driver->write_room) |
| 507 | room=tty->driver->write_room(tty); |
| 508 | |
| 509 | TRACE_PS("transmit_block %x, room %d, length %d", |
| 510 | (int)pBlock, room, pBlock->length); |
| 511 | |
| 512 | while(pInfo->tx_position < pBlock->length) |
| 513 | { |
| 514 | if(room<2) |
| 515 | break; |
| 516 | |
| 517 | if(pBlock->data[pInfo->tx_position]==DLE) |
| 518 | { |
| 519 | /* send additional DLE char: */ |
| 520 | put_char(pInfo, DLE); |
| 521 | } |
| 522 | put_char(pInfo, pBlock->data[pInfo->tx_position++]); |
| 523 | |
| 524 | room--; |
| 525 | } |
| 526 | |
| 527 | if((pInfo->tx_position == pBlock->length) && (room>=3)) |
| 528 | { |
| 529 | put_char(pInfo, DLE); |
| 530 | put_char(pInfo, ETX); |
| 531 | if(pInfo->flags & R3964_BCC) |
| 532 | { |
| 533 | put_char(pInfo, pInfo->bcc); |
| 534 | } |
| 535 | pInfo->state = R3964_WAIT_FOR_TX_ACK; |
| 536 | mod_timer(&pInfo->tmr, jiffies + R3964_TO_QVZ); |
| 537 | } |
| 538 | flush(pInfo); |
| 539 | } |
| 540 | |
| 541 | static void on_receive_block(struct r3964_info *pInfo) |
| 542 | { |
| 543 | unsigned int length; |
| 544 | struct r3964_client_info *pClient; |
| 545 | struct r3964_block_header *pBlock; |
| 546 | |
| 547 | length=pInfo->rx_position; |
| 548 | |
| 549 | /* compare byte checksum characters: */ |
| 550 | if(pInfo->flags & R3964_BCC) |
| 551 | { |
| 552 | if(pInfo->bcc!=pInfo->last_rx) |
| 553 | { |
| 554 | TRACE_PE("checksum error - got %x but expected %x", |
| 555 | pInfo->last_rx, pInfo->bcc); |
| 556 | pInfo->flags |= R3964_CHECKSUM; |
| 557 | } |
| 558 | } |
| 559 | |
| 560 | /* check for errors (parity, overrun,...): */ |
| 561 | if(pInfo->flags & R3964_ERROR) |
| 562 | { |
| 563 | TRACE_PE("on_receive_block - transmission failed error %x", |
| 564 | pInfo->flags & R3964_ERROR); |
| 565 | |
| 566 | put_char(pInfo, NAK); |
| 567 | flush(pInfo); |
| 568 | if(pInfo->nRetry<R3964_MAX_RETRIES) |
| 569 | { |
| 570 | pInfo->state=R3964_WAIT_FOR_RX_REPEAT; |
| 571 | pInfo->nRetry++; |
| 572 | mod_timer(&pInfo->tmr, jiffies + R3964_TO_RX_PANIC); |
| 573 | } |
| 574 | else |
| 575 | { |
| 576 | TRACE_PE("on_receive_block - failed after max retries"); |
| 577 | pInfo->state=R3964_IDLE; |
| 578 | } |
| 579 | return; |
| 580 | } |
| 581 | |
| 582 | |
| 583 | /* received block; submit DLE: */ |
| 584 | put_char(pInfo, DLE); |
| 585 | flush(pInfo); |
| 586 | del_timer_sync(&pInfo->tmr); |
| 587 | TRACE_PS(" rx success: got %d chars", length); |
| 588 | |
| 589 | /* prepare struct r3964_block_header: */ |
| 590 | pBlock = kmalloc(length+sizeof(struct r3964_block_header), GFP_KERNEL); |
| 591 | TRACE_M("on_receive_block - kmalloc %x",(int)pBlock); |
| 592 | |
| 593 | if(pBlock==NULL) |
| 594 | return; |
| 595 | |
| 596 | pBlock->length = length; |
| 597 | pBlock->data = ((unsigned char*)pBlock)+sizeof(struct r3964_block_header); |
| 598 | pBlock->locks = 0; |
| 599 | pBlock->next = NULL; |
| 600 | pBlock->owner = NULL; |
| 601 | |
| 602 | memcpy(pBlock->data, pInfo->rx_buf, length); |
| 603 | |
| 604 | /* queue block into rx_queue: */ |
| 605 | add_rx_queue(pInfo, pBlock); |
| 606 | |
| 607 | /* notify attached client processes: */ |
| 608 | for(pClient=pInfo->firstClient; pClient; pClient=pClient->next) |
| 609 | { |
| 610 | if(pClient->sig_flags & R3964_SIG_DATA) |
| 611 | { |
| 612 | add_msg(pClient, R3964_MSG_DATA, length, R3964_OK, pBlock); |
| 613 | } |
| 614 | } |
| 615 | wake_up_interruptible (&pInfo->read_wait); |
| 616 | |
| 617 | pInfo->state = R3964_IDLE; |
| 618 | |
| 619 | trigger_transmit(pInfo); |
| 620 | } |
| 621 | |
| 622 | |
| 623 | static void receive_char(struct r3964_info *pInfo, const unsigned char c) |
| 624 | { |
| 625 | switch(pInfo->state) |
| 626 | { |
| 627 | case R3964_TX_REQUEST: |
| 628 | if(c==DLE) |
| 629 | { |
| 630 | TRACE_PS("TX_REQUEST - got DLE"); |
| 631 | |
| 632 | pInfo->state = R3964_TRANSMITTING; |
| 633 | pInfo->tx_position = 0; |
| 634 | |
| 635 | transmit_block(pInfo); |
| 636 | } |
| 637 | else if(c==STX) |
| 638 | { |
| 639 | if(pInfo->nRetry==0) |
| 640 | { |
| 641 | TRACE_PE("TX_REQUEST - init conflict"); |
| 642 | if(pInfo->priority == R3964_SLAVE) |
| 643 | { |
| 644 | goto start_receiving; |
| 645 | } |
| 646 | } |
| 647 | else |
| 648 | { |
| 649 | TRACE_PE("TX_REQUEST - secondary init conflict!?" |
| 650 | " Switching to SLAVE mode for next rx."); |
| 651 | goto start_receiving; |
| 652 | } |
| 653 | } |
| 654 | else |
| 655 | { |
| 656 | TRACE_PE("TX_REQUEST - char != DLE: %x", c); |
| 657 | retry_transmit(pInfo); |
| 658 | } |
| 659 | break; |
| 660 | case R3964_TRANSMITTING: |
| 661 | if(c==NAK) |
| 662 | { |
| 663 | TRACE_PE("TRANSMITTING - got NAK"); |
| 664 | retry_transmit(pInfo); |
| 665 | } |
| 666 | else |
| 667 | { |
| 668 | TRACE_PE("TRANSMITTING - got invalid char"); |
| 669 | |
| 670 | pInfo->state = R3964_WAIT_ZVZ_BEFORE_TX_RETRY; |
| 671 | mod_timer(&pInfo->tmr, jiffies + R3964_TO_ZVZ); |
| 672 | } |
| 673 | break; |
| 674 | case R3964_WAIT_FOR_TX_ACK: |
| 675 | if(c==DLE) |
| 676 | { |
| 677 | TRACE_PS("WAIT_FOR_TX_ACK - got DLE"); |
| 678 | remove_from_tx_queue(pInfo, R3964_OK); |
| 679 | |
| 680 | pInfo->state = R3964_IDLE; |
| 681 | trigger_transmit(pInfo); |
| 682 | } |
| 683 | else |
| 684 | { |
| 685 | retry_transmit(pInfo); |
| 686 | } |
| 687 | break; |
| 688 | case R3964_WAIT_FOR_RX_REPEAT: |
| 689 | /* FALLTROUGH */ |
| 690 | case R3964_IDLE: |
| 691 | if(c==STX) |
| 692 | { |
| 693 | /* Prevent rx_queue from overflow: */ |
| 694 | if(pInfo->blocks_in_rx_queue >= R3964_MAX_BLOCKS_IN_RX_QUEUE) |
| 695 | { |
| 696 | TRACE_PE("IDLE - got STX but no space in rx_queue!"); |
| 697 | pInfo->state=R3964_WAIT_FOR_RX_BUF; |
| 698 | mod_timer(&pInfo->tmr, R3964_TO_NO_BUF); |
| 699 | break; |
| 700 | } |
| 701 | start_receiving: |
| 702 | /* Ok, start receiving: */ |
| 703 | TRACE_PS("IDLE - got STX"); |
| 704 | pInfo->rx_position = 0; |
| 705 | pInfo->last_rx = 0; |
| 706 | pInfo->flags &= ~R3964_ERROR; |
| 707 | pInfo->state=R3964_RECEIVING; |
| 708 | mod_timer(&pInfo->tmr, R3964_TO_ZVZ); |
| 709 | pInfo->nRetry = 0; |
| 710 | put_char(pInfo, DLE); |
| 711 | flush(pInfo); |
| 712 | pInfo->bcc = 0; |
| 713 | } |
| 714 | break; |
| 715 | case R3964_RECEIVING: |
| 716 | if(pInfo->rx_position < RX_BUF_SIZE) |
| 717 | { |
| 718 | pInfo->bcc ^= c; |
| 719 | |
| 720 | if(c==DLE) |
| 721 | { |
| 722 | if(pInfo->last_rx==DLE) |
| 723 | { |
| 724 | pInfo->last_rx = 0; |
| 725 | goto char_to_buf; |
| 726 | } |
| 727 | pInfo->last_rx = DLE; |
| 728 | break; |
| 729 | } |
| 730 | else if((c==ETX) && (pInfo->last_rx==DLE)) |
| 731 | { |
| 732 | if(pInfo->flags & R3964_BCC) |
| 733 | { |
| 734 | pInfo->state = R3964_WAIT_FOR_BCC; |
| 735 | mod_timer(&pInfo->tmr, R3964_TO_ZVZ); |
| 736 | } |
| 737 | else |
| 738 | { |
| 739 | on_receive_block(pInfo); |
| 740 | } |
| 741 | } |
| 742 | else |
| 743 | { |
| 744 | pInfo->last_rx = c; |
| 745 | char_to_buf: |
| 746 | pInfo->rx_buf[pInfo->rx_position++] = c; |
| 747 | mod_timer(&pInfo->tmr, R3964_TO_ZVZ); |
| 748 | } |
| 749 | } |
| 750 | /* else: overflow-msg? BUF_SIZE>MTU; should not happen? */ |
| 751 | break; |
| 752 | case R3964_WAIT_FOR_BCC: |
| 753 | pInfo->last_rx = c; |
| 754 | on_receive_block(pInfo); |
| 755 | break; |
| 756 | } |
| 757 | } |
| 758 | |
| 759 | static void receive_error(struct r3964_info *pInfo, const char flag) |
| 760 | { |
| 761 | switch (flag) |
| 762 | { |
| 763 | case TTY_NORMAL: |
| 764 | break; |
| 765 | case TTY_BREAK: |
| 766 | TRACE_PE("received break") |
| 767 | pInfo->flags |= R3964_BREAK; |
| 768 | break; |
| 769 | case TTY_PARITY: |
| 770 | TRACE_PE("parity error") |
| 771 | pInfo->flags |= R3964_PARITY; |
| 772 | break; |
| 773 | case TTY_FRAME: |
| 774 | TRACE_PE("frame error") |
| 775 | pInfo->flags |= R3964_FRAME; |
| 776 | break; |
| 777 | case TTY_OVERRUN: |
| 778 | TRACE_PE("frame overrun") |
| 779 | pInfo->flags |= R3964_OVERRUN; |
| 780 | break; |
| 781 | default: |
| 782 | TRACE_PE("receive_error - unknown flag %d", flag); |
| 783 | pInfo->flags |= R3964_UNKNOWN; |
| 784 | break; |
| 785 | } |
| 786 | } |
| 787 | |
| 788 | static void on_timeout(unsigned long priv) |
| 789 | { |
| 790 | struct r3964_info *pInfo = (void *)priv; |
| 791 | |
| 792 | switch(pInfo->state) |
| 793 | { |
| 794 | case R3964_TX_REQUEST: |
| 795 | TRACE_PE("TX_REQUEST - timeout"); |
| 796 | retry_transmit(pInfo); |
| 797 | break; |
| 798 | case R3964_WAIT_ZVZ_BEFORE_TX_RETRY: |
| 799 | put_char(pInfo, NAK); |
| 800 | flush(pInfo); |
| 801 | retry_transmit(pInfo); |
| 802 | break; |
| 803 | case R3964_WAIT_FOR_TX_ACK: |
| 804 | TRACE_PE("WAIT_FOR_TX_ACK - timeout"); |
| 805 | retry_transmit(pInfo); |
| 806 | break; |
| 807 | case R3964_WAIT_FOR_RX_BUF: |
| 808 | TRACE_PE("WAIT_FOR_RX_BUF - timeout"); |
| 809 | put_char(pInfo, NAK); |
| 810 | flush(pInfo); |
| 811 | pInfo->state=R3964_IDLE; |
| 812 | break; |
| 813 | case R3964_RECEIVING: |
| 814 | TRACE_PE("RECEIVING - timeout after %d chars", |
| 815 | pInfo->rx_position); |
| 816 | put_char(pInfo, NAK); |
| 817 | flush(pInfo); |
| 818 | pInfo->state=R3964_IDLE; |
| 819 | break; |
| 820 | case R3964_WAIT_FOR_RX_REPEAT: |
| 821 | TRACE_PE("WAIT_FOR_RX_REPEAT - timeout"); |
| 822 | pInfo->state=R3964_IDLE; |
| 823 | break; |
| 824 | case R3964_WAIT_FOR_BCC: |
| 825 | TRACE_PE("WAIT_FOR_BCC - timeout"); |
| 826 | put_char(pInfo, NAK); |
| 827 | flush(pInfo); |
| 828 | pInfo->state=R3964_IDLE; |
| 829 | break; |
| 830 | } |
| 831 | } |
| 832 | |
| 833 | static struct r3964_client_info *findClient( |
| 834 | struct r3964_info *pInfo, pid_t pid) |
| 835 | { |
| 836 | struct r3964_client_info *pClient; |
| 837 | |
| 838 | for(pClient=pInfo->firstClient; pClient; pClient=pClient->next) |
| 839 | { |
| 840 | if(pClient->pid == pid) |
| 841 | { |
| 842 | return pClient; |
| 843 | } |
| 844 | } |
| 845 | return NULL; |
| 846 | } |
| 847 | |
| 848 | static int enable_signals(struct r3964_info *pInfo, pid_t pid, int arg) |
| 849 | { |
| 850 | struct r3964_client_info *pClient; |
| 851 | struct r3964_client_info **ppClient; |
| 852 | struct r3964_message *pMsg; |
| 853 | |
| 854 | if((arg & R3964_SIG_ALL)==0) |
| 855 | { |
| 856 | /* Remove client from client list */ |
| 857 | for(ppClient=&pInfo->firstClient; *ppClient; ppClient=&(*ppClient)->next) |
| 858 | { |
| 859 | pClient = *ppClient; |
| 860 | |
| 861 | if(pClient->pid == pid) |
| 862 | { |
| 863 | TRACE_PS("removing client %d from client list", pid); |
| 864 | *ppClient = pClient->next; |
| 865 | while(pClient->msg_count) |
| 866 | { |
| 867 | pMsg=remove_msg(pInfo, pClient); |
| 868 | if(pMsg) |
| 869 | { |
| 870 | kfree(pMsg); |
| 871 | TRACE_M("enable_signals - msg kfree %x",(int)pMsg); |
| 872 | } |
| 873 | } |
| 874 | kfree(pClient); |
| 875 | TRACE_M("enable_signals - kfree %x",(int)pClient); |
| 876 | return 0; |
| 877 | } |
| 878 | } |
| 879 | return -EINVAL; |
| 880 | } |
| 881 | else |
| 882 | { |
| 883 | pClient=findClient(pInfo, pid); |
| 884 | if(pClient) |
| 885 | { |
| 886 | /* update signal options */ |
| 887 | pClient->sig_flags=arg; |
| 888 | } |
| 889 | else |
| 890 | { |
| 891 | /* add client to client list */ |
| 892 | pClient=kmalloc(sizeof(struct r3964_client_info), GFP_KERNEL); |
| 893 | TRACE_M("enable_signals - kmalloc %x",(int)pClient); |
| 894 | if(pClient==NULL) |
| 895 | return -ENOMEM; |
| 896 | |
| 897 | TRACE_PS("add client %d to client list", pid); |
| 898 | spin_lock_init(&pClient->lock); |
| 899 | pClient->sig_flags=arg; |
| 900 | pClient->pid = pid; |
| 901 | pClient->next=pInfo->firstClient; |
| 902 | pClient->first_msg = NULL; |
| 903 | pClient->last_msg = NULL; |
| 904 | pClient->next_block_to_read = NULL; |
| 905 | pClient->msg_count = 0; |
| 906 | pInfo->firstClient=pClient; |
| 907 | } |
| 908 | } |
| 909 | |
| 910 | return 0; |
| 911 | } |
| 912 | |
| 913 | static int read_telegram(struct r3964_info *pInfo, pid_t pid, unsigned char __user *buf) |
| 914 | { |
| 915 | struct r3964_client_info *pClient; |
| 916 | struct r3964_block_header *block; |
| 917 | |
| 918 | if(!buf) |
| 919 | { |
| 920 | return -EINVAL; |
| 921 | } |
| 922 | |
| 923 | pClient=findClient(pInfo,pid); |
| 924 | if(pClient==NULL) |
| 925 | { |
| 926 | return -EINVAL; |
| 927 | } |
| 928 | |
| 929 | block=pClient->next_block_to_read; |
| 930 | if(!block) |
| 931 | { |
| 932 | return 0; |
| 933 | } |
| 934 | else |
| 935 | { |
| 936 | if (copy_to_user (buf, block->data, block->length)) |
| 937 | return -EFAULT; |
| 938 | |
| 939 | remove_client_block(pInfo, pClient); |
| 940 | return block->length; |
| 941 | } |
| 942 | |
| 943 | return -EINVAL; |
| 944 | } |
| 945 | |
| 946 | static void add_msg(struct r3964_client_info *pClient, int msg_id, int arg, |
| 947 | int error_code, struct r3964_block_header *pBlock) |
| 948 | { |
| 949 | struct r3964_message *pMsg; |
| 950 | unsigned long flags; |
| 951 | |
| 952 | if(pClient->msg_count<R3964_MAX_MSG_COUNT-1) |
| 953 | { |
| 954 | queue_the_message: |
| 955 | |
| 956 | pMsg = kmalloc(sizeof(struct r3964_message), GFP_KERNEL); |
| 957 | TRACE_M("add_msg - kmalloc %x",(int)pMsg); |
| 958 | if(pMsg==NULL) { |
| 959 | return; |
| 960 | } |
| 961 | |
| 962 | spin_lock_irqsave(&pClient->lock, flags); |
| 963 | |
| 964 | pMsg->msg_id = msg_id; |
| 965 | pMsg->arg = arg; |
| 966 | pMsg->error_code = error_code; |
| 967 | pMsg->block = pBlock; |
| 968 | pMsg->next = NULL; |
| 969 | |
| 970 | if(pClient->last_msg==NULL) |
| 971 | { |
| 972 | pClient->first_msg=pClient->last_msg=pMsg; |
| 973 | } |
| 974 | else |
| 975 | { |
| 976 | pClient->last_msg->next = pMsg; |
| 977 | pClient->last_msg=pMsg; |
| 978 | } |
| 979 | |
| 980 | pClient->msg_count++; |
| 981 | |
| 982 | if(pBlock!=NULL) |
| 983 | { |
| 984 | pBlock->locks++; |
| 985 | } |
| 986 | spin_unlock_irqrestore(&pClient->lock, flags); |
| 987 | } |
| 988 | else |
| 989 | { |
| 990 | if((pClient->last_msg->msg_id == R3964_MSG_ACK) |
| 991 | && (pClient->last_msg->error_code==R3964_OVERFLOW)) |
| 992 | { |
| 993 | pClient->last_msg->arg++; |
| 994 | TRACE_PE("add_msg - inc prev OVERFLOW-msg"); |
| 995 | } |
| 996 | else |
| 997 | { |
| 998 | msg_id = R3964_MSG_ACK; |
| 999 | arg = 0; |
| 1000 | error_code = R3964_OVERFLOW; |
| 1001 | pBlock = NULL; |
| 1002 | TRACE_PE("add_msg - queue OVERFLOW-msg"); |
| 1003 | goto queue_the_message; |
| 1004 | } |
| 1005 | } |
| 1006 | /* Send SIGIO signal to client process: */ |
| 1007 | if(pClient->sig_flags & R3964_USE_SIGIO) |
| 1008 | { |
| 1009 | kill_proc(pClient->pid, SIGIO, 1); |
| 1010 | } |
| 1011 | } |
| 1012 | |
| 1013 | static struct r3964_message *remove_msg(struct r3964_info *pInfo, |
| 1014 | struct r3964_client_info *pClient) |
| 1015 | { |
| 1016 | struct r3964_message *pMsg=NULL; |
| 1017 | unsigned long flags; |
| 1018 | |
| 1019 | if(pClient->first_msg) |
| 1020 | { |
| 1021 | spin_lock_irqsave(&pClient->lock, flags); |
| 1022 | |
| 1023 | pMsg = pClient->first_msg; |
| 1024 | pClient->first_msg = pMsg->next; |
| 1025 | if(pClient->first_msg==NULL) |
| 1026 | { |
| 1027 | pClient->last_msg = NULL; |
| 1028 | } |
| 1029 | |
| 1030 | pClient->msg_count--; |
| 1031 | if(pMsg->block) |
| 1032 | { |
| 1033 | remove_client_block(pInfo, pClient); |
| 1034 | pClient->next_block_to_read = pMsg->block; |
| 1035 | } |
| 1036 | spin_unlock_irqrestore(&pClient->lock, flags); |
| 1037 | } |
| 1038 | return pMsg; |
| 1039 | } |
| 1040 | |
| 1041 | static void remove_client_block(struct r3964_info *pInfo, |
| 1042 | struct r3964_client_info *pClient) |
| 1043 | { |
| 1044 | struct r3964_block_header *block; |
| 1045 | |
| 1046 | TRACE_PS("remove_client_block PID %d", pClient->pid); |
| 1047 | |
| 1048 | block=pClient->next_block_to_read; |
| 1049 | if(block) |
| 1050 | { |
| 1051 | block->locks--; |
| 1052 | if(block->locks==0) |
| 1053 | { |
| 1054 | remove_from_rx_queue(pInfo, block); |
| 1055 | } |
| 1056 | } |
| 1057 | pClient->next_block_to_read = NULL; |
| 1058 | } |
| 1059 | |
| 1060 | |
| 1061 | /************************************************************* |
| 1062 | * Line discipline routines |
| 1063 | *************************************************************/ |
| 1064 | |
| 1065 | static int r3964_open(struct tty_struct *tty) |
| 1066 | { |
| 1067 | struct r3964_info *pInfo; |
| 1068 | |
| 1069 | TRACE_L("open"); |
| 1070 | TRACE_L("tty=%x, PID=%d, disc_data=%x", |
| 1071 | (int)tty, current->pid, (int)tty->disc_data); |
| 1072 | |
| 1073 | pInfo=kmalloc(sizeof(struct r3964_info), GFP_KERNEL); |
| 1074 | TRACE_M("r3964_open - info kmalloc %x",(int)pInfo); |
| 1075 | |
| 1076 | if(!pInfo) |
| 1077 | { |
| 1078 | printk(KERN_ERR "r3964: failed to alloc info structure\n"); |
| 1079 | return -ENOMEM; |
| 1080 | } |
| 1081 | |
| 1082 | pInfo->rx_buf = kmalloc(RX_BUF_SIZE, GFP_KERNEL); |
| 1083 | TRACE_M("r3964_open - rx_buf kmalloc %x",(int)pInfo->rx_buf); |
| 1084 | |
| 1085 | if(!pInfo->rx_buf) |
| 1086 | { |
| 1087 | printk(KERN_ERR "r3964: failed to alloc receive buffer\n"); |
| 1088 | kfree(pInfo); |
| 1089 | TRACE_M("r3964_open - info kfree %x",(int)pInfo); |
| 1090 | return -ENOMEM; |
| 1091 | } |
| 1092 | |
| 1093 | pInfo->tx_buf = kmalloc(TX_BUF_SIZE, GFP_KERNEL); |
| 1094 | TRACE_M("r3964_open - tx_buf kmalloc %x",(int)pInfo->tx_buf); |
| 1095 | |
| 1096 | if(!pInfo->tx_buf) |
| 1097 | { |
| 1098 | printk(KERN_ERR "r3964: failed to alloc transmit buffer\n"); |
| 1099 | kfree(pInfo->rx_buf); |
| 1100 | TRACE_M("r3964_open - rx_buf kfree %x",(int)pInfo->rx_buf); |
| 1101 | kfree(pInfo); |
| 1102 | TRACE_M("r3964_open - info kfree %x",(int)pInfo); |
| 1103 | return -ENOMEM; |
| 1104 | } |
| 1105 | |
| 1106 | spin_lock_init(&pInfo->lock); |
| 1107 | pInfo->tty = tty; |
| 1108 | init_waitqueue_head (&pInfo->read_wait); |
| 1109 | pInfo->priority = R3964_MASTER; |
| 1110 | pInfo->rx_first = pInfo->rx_last = NULL; |
| 1111 | pInfo->tx_first = pInfo->tx_last = NULL; |
| 1112 | pInfo->rx_position = 0; |
| 1113 | pInfo->tx_position = 0; |
| 1114 | pInfo->last_rx = 0; |
| 1115 | pInfo->blocks_in_rx_queue = 0; |
| 1116 | pInfo->firstClient=NULL; |
| 1117 | pInfo->state=R3964_IDLE; |
| 1118 | pInfo->flags = R3964_DEBUG; |
| 1119 | pInfo->nRetry = 0; |
| 1120 | |
| 1121 | tty->disc_data = pInfo; |
| 1122 | |
| 1123 | init_timer(&pInfo->tmr); |
| 1124 | pInfo->tmr.data = (unsigned long)pInfo; |
| 1125 | pInfo->tmr.function = on_timeout; |
| 1126 | |
| 1127 | return 0; |
| 1128 | } |
| 1129 | |
| 1130 | static void r3964_close(struct tty_struct *tty) |
| 1131 | { |
| 1132 | struct r3964_info *pInfo=(struct r3964_info*)tty->disc_data; |
| 1133 | struct r3964_client_info *pClient, *pNext; |
| 1134 | struct r3964_message *pMsg; |
| 1135 | struct r3964_block_header *pHeader, *pNextHeader; |
| 1136 | unsigned long flags; |
| 1137 | |
| 1138 | TRACE_L("close"); |
| 1139 | |
| 1140 | /* |
| 1141 | * Make sure that our task queue isn't activated. If it |
| 1142 | * is, take it out of the linked list. |
| 1143 | */ |
| 1144 | del_timer_sync(&pInfo->tmr); |
| 1145 | |
| 1146 | /* Remove client-structs and message queues: */ |
| 1147 | pClient=pInfo->firstClient; |
| 1148 | while(pClient) |
| 1149 | { |
| 1150 | pNext=pClient->next; |
| 1151 | while(pClient->msg_count) |
| 1152 | { |
| 1153 | pMsg=remove_msg(pInfo, pClient); |
| 1154 | if(pMsg) |
| 1155 | { |
| 1156 | kfree(pMsg); |
| 1157 | TRACE_M("r3964_close - msg kfree %x",(int)pMsg); |
| 1158 | } |
| 1159 | } |
| 1160 | kfree(pClient); |
| 1161 | TRACE_M("r3964_close - client kfree %x",(int)pClient); |
| 1162 | pClient=pNext; |
| 1163 | } |
| 1164 | /* Remove jobs from tx_queue: */ |
| 1165 | spin_lock_irqsave(&pInfo->lock, flags); |
| 1166 | pHeader=pInfo->tx_first; |
| 1167 | pInfo->tx_first=pInfo->tx_last=NULL; |
| 1168 | spin_unlock_irqrestore(&pInfo->lock, flags); |
| 1169 | |
| 1170 | while(pHeader) |
| 1171 | { |
| 1172 | pNextHeader=pHeader->next; |
| 1173 | kfree(pHeader); |
| 1174 | pHeader=pNextHeader; |
| 1175 | } |
| 1176 | |
| 1177 | /* Free buffers: */ |
| 1178 | wake_up_interruptible(&pInfo->read_wait); |
| 1179 | kfree(pInfo->rx_buf); |
| 1180 | TRACE_M("r3964_close - rx_buf kfree %x",(int)pInfo->rx_buf); |
| 1181 | kfree(pInfo->tx_buf); |
| 1182 | TRACE_M("r3964_close - tx_buf kfree %x",(int)pInfo->tx_buf); |
| 1183 | kfree(pInfo); |
| 1184 | TRACE_M("r3964_close - info kfree %x",(int)pInfo); |
| 1185 | } |
| 1186 | |
| 1187 | static ssize_t r3964_read(struct tty_struct *tty, struct file *file, |
| 1188 | unsigned char __user *buf, size_t nr) |
| 1189 | { |
| 1190 | struct r3964_info *pInfo=(struct r3964_info*)tty->disc_data; |
| 1191 | struct r3964_client_info *pClient; |
| 1192 | struct r3964_message *pMsg; |
| 1193 | struct r3964_client_message theMsg; |
| 1194 | DECLARE_WAITQUEUE (wait, current); |
| 1195 | |
| 1196 | int pid = current->pid; |
| 1197 | int count; |
| 1198 | |
| 1199 | TRACE_L("read()"); |
| 1200 | |
| 1201 | pClient=findClient(pInfo, pid); |
| 1202 | if(pClient) |
| 1203 | { |
| 1204 | pMsg = remove_msg(pInfo, pClient); |
| 1205 | if(pMsg==NULL) |
| 1206 | { |
| 1207 | /* no messages available. */ |
| 1208 | if (file->f_flags & O_NONBLOCK) |
| 1209 | { |
| 1210 | return -EAGAIN; |
| 1211 | } |
| 1212 | /* block until there is a message: */ |
| 1213 | add_wait_queue(&pInfo->read_wait, &wait); |
| 1214 | repeat: |
| 1215 | current->state = TASK_INTERRUPTIBLE; |
| 1216 | pMsg = remove_msg(pInfo, pClient); |
| 1217 | if (!pMsg && !signal_pending(current)) |
| 1218 | { |
| 1219 | schedule(); |
| 1220 | goto repeat; |
| 1221 | } |
| 1222 | current->state = TASK_RUNNING; |
| 1223 | remove_wait_queue(&pInfo->read_wait, &wait); |
| 1224 | } |
| 1225 | |
| 1226 | /* If we still haven't got a message, we must have been signalled */ |
| 1227 | |
| 1228 | if (!pMsg) return -EINTR; |
| 1229 | |
| 1230 | /* deliver msg to client process: */ |
| 1231 | theMsg.msg_id = pMsg->msg_id; |
| 1232 | theMsg.arg = pMsg->arg; |
| 1233 | theMsg.error_code = pMsg->error_code; |
| 1234 | count = sizeof(struct r3964_client_message); |
| 1235 | |
| 1236 | kfree(pMsg); |
| 1237 | TRACE_M("r3964_read - msg kfree %x",(int)pMsg); |
| 1238 | |
| 1239 | if (copy_to_user(buf,&theMsg, count)) |
| 1240 | return -EFAULT; |
| 1241 | |
| 1242 | TRACE_PS("read - return %d", count); |
| 1243 | return count; |
| 1244 | } |
| 1245 | return -EPERM; |
| 1246 | } |
| 1247 | |
| 1248 | static ssize_t r3964_write(struct tty_struct * tty, struct file * file, |
| 1249 | const unsigned char *data, size_t count) |
| 1250 | { |
| 1251 | struct r3964_info *pInfo=(struct r3964_info*)tty->disc_data; |
| 1252 | struct r3964_block_header *pHeader; |
| 1253 | struct r3964_client_info *pClient; |
| 1254 | unsigned char *new_data; |
| 1255 | int pid; |
| 1256 | |
| 1257 | TRACE_L("write request, %d characters", count); |
| 1258 | /* |
| 1259 | * Verify the pointers |
| 1260 | */ |
| 1261 | |
| 1262 | if(!pInfo) |
| 1263 | return -EIO; |
| 1264 | |
| 1265 | /* |
| 1266 | * Ensure that the caller does not wish to send too much. |
| 1267 | */ |
| 1268 | if (count > R3964_MTU) |
| 1269 | { |
| 1270 | if (pInfo->flags & R3964_DEBUG) |
| 1271 | { |
| 1272 | TRACE_L (KERN_WARNING |
| 1273 | "r3964_write: truncating user packet " |
| 1274 | "from %u to mtu %d", count, R3964_MTU); |
| 1275 | } |
| 1276 | count = R3964_MTU; |
| 1277 | } |
| 1278 | /* |
| 1279 | * Allocate a buffer for the data and copy it from the buffer with header prepended |
| 1280 | */ |
| 1281 | new_data = kmalloc (count+sizeof(struct r3964_block_header), GFP_KERNEL); |
| 1282 | TRACE_M("r3964_write - kmalloc %x",(int)new_data); |
| 1283 | if (new_data == NULL) { |
| 1284 | if (pInfo->flags & R3964_DEBUG) |
| 1285 | { |
| 1286 | printk (KERN_ERR |
| 1287 | "r3964_write: no memory\n"); |
| 1288 | } |
| 1289 | return -ENOSPC; |
| 1290 | } |
| 1291 | |
| 1292 | pHeader = (struct r3964_block_header *)new_data; |
| 1293 | pHeader->data = new_data + sizeof(struct r3964_block_header); |
| 1294 | pHeader->length = count; |
| 1295 | pHeader->locks = 0; |
| 1296 | pHeader->owner = NULL; |
| 1297 | |
| 1298 | pid=current->pid; |
| 1299 | |
| 1300 | pClient=findClient(pInfo, pid); |
| 1301 | if(pClient) |
| 1302 | { |
| 1303 | pHeader->owner = pClient; |
| 1304 | } |
| 1305 | |
| 1306 | memcpy(pHeader->data, data, count); /* We already verified this */ |
| 1307 | |
| 1308 | if(pInfo->flags & R3964_DEBUG) |
| 1309 | { |
| 1310 | dump_block(pHeader->data, count); |
| 1311 | } |
| 1312 | |
| 1313 | /* |
| 1314 | * Add buffer to transmit-queue: |
| 1315 | */ |
| 1316 | add_tx_queue(pInfo, pHeader); |
| 1317 | trigger_transmit(pInfo); |
| 1318 | |
| 1319 | return 0; |
| 1320 | } |
| 1321 | |
| 1322 | static int r3964_ioctl(struct tty_struct * tty, struct file * file, |
| 1323 | unsigned int cmd, unsigned long arg) |
| 1324 | { |
| 1325 | struct r3964_info *pInfo=(struct r3964_info*)tty->disc_data; |
| 1326 | if(pInfo==NULL) |
| 1327 | return -EINVAL; |
| 1328 | switch(cmd) |
| 1329 | { |
| 1330 | case R3964_ENABLE_SIGNALS: |
| 1331 | return enable_signals(pInfo, current->pid, arg); |
| 1332 | case R3964_SETPRIORITY: |
| 1333 | if(arg<R3964_MASTER || arg>R3964_SLAVE) |
| 1334 | return -EINVAL; |
| 1335 | pInfo->priority = arg & 0xff; |
| 1336 | return 0; |
| 1337 | case R3964_USE_BCC: |
| 1338 | if(arg) |
| 1339 | pInfo->flags |= R3964_BCC; |
| 1340 | else |
| 1341 | pInfo->flags &= ~R3964_BCC; |
| 1342 | return 0; |
| 1343 | case R3964_READ_TELEGRAM: |
| 1344 | return read_telegram(pInfo, current->pid, (unsigned char __user *)arg); |
| 1345 | default: |
| 1346 | return -ENOIOCTLCMD; |
| 1347 | } |
| 1348 | } |
| 1349 | |
| 1350 | static void r3964_set_termios(struct tty_struct *tty, struct termios * old) |
| 1351 | { |
| 1352 | TRACE_L("set_termios"); |
| 1353 | } |
| 1354 | |
| 1355 | /* Called without the kernel lock held - fine */ |
| 1356 | static unsigned int r3964_poll(struct tty_struct * tty, struct file * file, |
| 1357 | struct poll_table_struct *wait) |
| 1358 | { |
| 1359 | struct r3964_info *pInfo=(struct r3964_info*)tty->disc_data; |
| 1360 | int pid=current->pid; |
| 1361 | struct r3964_client_info *pClient; |
| 1362 | struct r3964_message *pMsg=NULL; |
| 1363 | unsigned long flags; |
| 1364 | int result = POLLOUT; |
| 1365 | |
| 1366 | TRACE_L("POLL"); |
| 1367 | |
| 1368 | pClient=findClient(pInfo,pid); |
| 1369 | if(pClient) |
| 1370 | { |
| 1371 | poll_wait(file, &pInfo->read_wait, wait); |
| 1372 | spin_lock_irqsave(&pInfo->lock, flags); |
| 1373 | pMsg=pClient->first_msg; |
| 1374 | spin_unlock_irqrestore(&pInfo->lock, flags); |
| 1375 | if(pMsg) |
| 1376 | result |= POLLIN | POLLRDNORM; |
| 1377 | } |
| 1378 | else |
| 1379 | { |
| 1380 | result = -EINVAL; |
| 1381 | } |
| 1382 | return result; |
| 1383 | } |
| 1384 | |
| 1385 | static void r3964_receive_buf(struct tty_struct *tty, const unsigned char *cp, |
| 1386 | char *fp, int count) |
| 1387 | { |
| 1388 | struct r3964_info *pInfo=(struct r3964_info*)tty->disc_data; |
| 1389 | const unsigned char *p; |
| 1390 | char *f, flags = 0; |
| 1391 | int i; |
| 1392 | |
| 1393 | for (i=count, p = cp, f = fp; i; i--, p++) { |
| 1394 | if (f) |
| 1395 | flags = *f++; |
| 1396 | if(flags==TTY_NORMAL) |
| 1397 | { |
| 1398 | receive_char(pInfo, *p); |
| 1399 | } |
| 1400 | else |
| 1401 | { |
| 1402 | receive_error(pInfo, flags); |
| 1403 | } |
| 1404 | |
| 1405 | } |
| 1406 | } |
| 1407 | |
| 1408 | static int r3964_receive_room(struct tty_struct *tty) |
| 1409 | { |
| 1410 | TRACE_L("receive_room"); |
| 1411 | return -1; |
| 1412 | } |
| 1413 | |
| 1414 | |
| 1415 | MODULE_LICENSE("GPL"); |
| 1416 | MODULE_ALIAS_LDISC(N_R3964); |