/* ChibiOS/RT - Copyright (C) 2006,2007,2008,2009,2010, 2011,2012,2013 Giovanni Di Sirio. This file is part of ChibiOS/RT. ChibiOS/RT is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 3 of the License, or (at your option) any later version. ChibiOS/RT is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program. If not, see . */ /** * @file hal_channels.h * @brief I/O channels access. * @details This header defines an abstract interface useful to access generic * I/O serial devices in a standardized way. * * @addtogroup IO_CHANNEL * @details This module defines an abstract interface for I/O channels by * extending the @p BaseSequentialStream interface.
* Note that no code is present, I/O channels are just abstract * interface like structures, you should look at the systems as * to a set of abstract C++ classes (even if written in C). * Specific device drivers can use/extend the interface and * implement them.
* This system has the advantage to make the access to channels * independent from the implementation logic. * @{ */ #ifndef _HAL_CHANNELS_H_ #define _HAL_CHANNELS_H_ /** * @brief @p BaseChannel specific methods. */ #define _base_channel_methods \ _base_sequential_stream_methods \ /* Channel put method with timeout specification.*/ \ msg_t (*putt)(void *instance, uint8_t b, systime_t time); \ /* Channel get method with timeout specification.*/ \ msg_t (*gett)(void *instance, systime_t time); \ /* Channel write method with timeout specification.*/ \ size_t (*writet)(void *instance, const uint8_t *bp, \ size_t n, systime_t time); \ /* Channel read method with timeout specification.*/ \ size_t (*readt)(void *instance, uint8_t *bp, size_t n, systime_t time); /** * @brief @p BaseChannel specific data. * @note It is empty because @p BaseChannel is only an interface without * implementation. */ #define _base_channel_data \ _base_sequential_stream_data /** * @extends BaseSequentialStreamVMT * * @brief @p BaseChannel virtual methods table. */ struct BaseChannelVMT { _base_channel_methods }; /** * @extends BaseSequentialStream * * @brief Base channel class. * @details This class represents a generic, byte-wide, I/O channel. This class * introduces generic I/O primitives with timeout specification. */ typedef struct { /** @brief Virtual Methods Table.*/ const struct BaseChannelVMT *vmt; _base_channel_data } BaseChannel; /** * @name Macro Functions (BaseChannel) * @{ */ /** * @brief Channel blocking byte write with timeout. * @details This function writes a byte value to a channel. If the channel * is not ready to accept data then the calling thread is suspended. * * @param[in] ip pointer to a @p BaseChannel or derived class * @param[in] b the byte value to be written to the channel * @param[in] time the number of ticks before the operation timeouts, * the following special values are allowed: * - @a TIME_IMMEDIATE immediate timeout. * - @a TIME_INFINITE no timeout. * . * @return The operation status. * @retval STM_OK if the operation succeeded. * @retval STM_TIMEOUT if the specified time expired. * @retval STM_RESET if the channel associated queue (if any) was reset. * * @api */ #define chnPutTimeout(ip, b, time) ((ip)->vmt->putt(ip, b, time)) /** * @brief Channel blocking byte read with timeout. * @details This function reads a byte value from a channel. If the data * is not available then the calling thread is suspended. * * @param[in] ip pointer to a @p BaseChannel or derived class * @param[in] time the number of ticks before the operation timeouts, * the following special values are allowed: * - @a TIME_IMMEDIATE immediate timeout. * - @a TIME_INFINITE no timeout. * . * @return A byte value from the queue. * @retval STM_TIMEOUT if the specified time expired. * @retval STM_RESET if the channel associated queue (if any) has been * reset. * * @api */ #define chnGetTimeout(ip, time) ((ip)->vmt->gett(ip, time)) /** * @brief Channel blocking write. * @details The function writes data from a buffer to a channel. If the channel * is not ready to accept data then the calling thread is suspended. * * @param[in] ip pointer to a @p BaseChannel or derived class * @param[out] bp pointer to the data buffer * @param[in] n the maximum amount of data to be transferred * * @return The number of bytes transferred. * * @api */ #define chnWrite(ip, bp, n) streamWrite(ip, bp, n) /** * @brief Channel blocking write with timeout. * @details The function writes data from a buffer to a channel. If the channel * is not ready to accept data then the calling thread is suspended. * * @param[in] ip pointer to a @p BaseChannel or derived class * @param[out] bp pointer to the data buffer * @param[in] n the maximum amount of data to be transferred * @param[in] time the number of ticks before the operation timeouts, * the following special values are allowed: * - @a TIME_IMMEDIATE immediate timeout. * - @a TIME_INFINITE no timeout. * . * @return The number of bytes transferred. * * @api */ #define chnWriteTimeout(ip, bp, n, time) ((ip)->vmt->writet(ip, bp, n, time)) /** * @brief Channel blocking read. * @details The function reads data from a channel into a buffer. If the data * is not available then the calling thread is suspended. * * @param[in] ip pointer to a @p BaseChannel or derived class * @param[in] bp pointer to the data buffer * @param[in] n the maximum amount of data to be transferred * * @return The number of bytes transferred. * * @api */ #define chnRead(ip, bp, n) streamRead(ip, bp, n) /** * @brief Channel blocking read with timeout. * @details The function reads data from a channel into a buffer. If the data * is not available then the calling thread is suspended. * * @param[in] ip pointer to a @p BaseChannel or derived class * @param[in] bp pointer to the data buffer * @param[in] n the maximum amount of data to be transferred * @param[in] time the number of ticks before the operation timeouts, * the following special values are allowed: * - @a TIME_IMMEDIATE immediate timeout. * - @a TIME_INFINITE no timeout. * . * @return The number of bytes transferred. * * @api */ #define chnReadTimeout(ip, bp, n, time) ((ip)->vmt->readt(ip, bp, n, time)) /** @} */ /** * @name I/O status flags added to the event listener * @{ */ /** @brief No pending conditions.*/ #define CHN_NO_ERROR 0 /** @brief Connection happened.*/ #define CHN_CONNECTED 1 /** @brief Disconnection happened.*/ #define CHN_DISCONNECTED 2 /** @brief Data available in the input queue.*/ #define CHN_INPUT_AVAILABLE 4 /** @brief Output queue empty.*/ #define CHN_OUTPUT_EMPTY 8 /** @brief Transmission end.*/ #define CHN_TRANSMISSION_END 16 /** @} */ /** * @brief @p BaseAsynchronousChannel specific methods. */ #define _base_asynchronous_channel_methods \ _base_channel_methods \ /** * @brief @p BaseAsynchronousChannel specific data. */ #define _base_asynchronous_channel_data \ _base_channel_data \ /* I/O condition event source.*/ \ event_source_t event; /** * @extends BaseChannelVMT * * @brief @p BaseAsynchronousChannel virtual methods table. */ struct BaseAsynchronousChannelVMT { _base_asynchronous_channel_methods }; /** * @extends BaseChannel * * @brief Base asynchronous channel class. * @details This class extends @p BaseChannel by adding event sources fields * for asynchronous I/O for use in an event-driven environment. */ typedef struct { /** @brief Virtual Methods Table.*/ const struct BaseAsynchronousChannelVMT *vmt; _base_asynchronous_channel_data } BaseAsynchronousChannel; /** * @name Macro Functions (BaseAsynchronousChannel) * @{ */ /** * @brief Returns the I/O condition event source. * @details The event source is broadcasted when an I/O condition happens. * * @param[in] ip pointer to a @p BaseAsynchronousChannel or derived * class * @return A pointer to an @p EventSource object. * * @api */ #define chnGetEventSource(ip) (&((ip)->event)) /** * @brief Adds status flags to the listeners's flags mask. * @details This function is usually called from the I/O ISRs in order to * notify I/O conditions such as data events, errors, signal * changes etc. * * @param[in] ip pointer to a @p BaseAsynchronousChannel or derived * class * @param[in] flags condition flags to be added to the listener flags mask * * @iclass */ #define chnAddFlagsI(ip, flags) { \ osalEventBroadcastFlagsI(&(ip)->event, flags); \ } /** @} */ #endif /* _HAL_CHANNELS_H_ */ /** @} */ id='n206' href='#n206'>206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868