/* $Id: plugin_i2c_sensors.c,v 1.25 2006/02/25 13:36:33 geronet Exp $ * * I2C sensors plugin * * Copyright (C) 2003, 2004 Xavier Vello * Copyright (C) 2004 The LCD4Linux Team * * This file is part of LCD4Linux. * * LCD4Linux 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 2, or (at your option) * any later version. * * LCD4Linux 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, write to the Free Software * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. * * * $Log: plugin_i2c_sensors.c,v $ * Revision 1.25 2006/02/25 13:36:33 geronet * updated indent.sh, applied coding style * * Revision 1.24 2005/05/08 04:32:44 reinelt * CodingStyle added and applied * * Revision 1.23 2005/04/01 05:16:04 reinelt * moved plugin init stuff to a seperate function called on first use * * Revision 1.22 2005/01/18 06:30:23 reinelt * added (C) to all copyright statements * * Revision 1.21 2004/06/26 12:05:00 reinelt * * uh-oh... the last CVS log message messed up things a lot... * * Revision 1.20 2004/06/26 09:27:21 reinelt * * added '-W' to CFLAGS * changed all C++ comments to C ones * cleaned up a lot of signed/unsigned mistakes * * Revision 1.19 2004/06/20 10:09:56 reinelt * * 'const'ified the whole source * * Revision 1.18 2004/06/17 06:23:43 reinelt * * hash handling rewritten to solve performance issues * * Revision 1.17 2004/06/05 14:56:48 reinelt * * Cwlinux splash screen fixed * USBLCD splash screen fixed * plugin_i2c qprintf("%f") replaced with snprintf() * * Revision 1.16 2004/06/01 06:45:30 reinelt * * some Fixme's processed * documented some code * * Revision 1.15 2004/05/31 21:05:13 reinelt * * fixed lots of bugs in the Cwlinux driver * do not emit EAGAIN error on the first retry * made plugin_i2c_sensors a bit less 'chatty' * moved init and exit functions to the bottom of plugin_pop3 * * Revision 1.14 2004/05/09 05:41:42 reinelt * * i2c fix for kernel 2.6.5 (temp_input1 vs. temp1_input) from Xavier * * Revision 1.13 2004/03/03 03:47:04 reinelt * big patch from Martin Hejl: * - use qprintf() where appropriate * - save CPU cycles on gettimeofday() * - add quit() functions to free allocated memory * - fixed lots of memory leaks * * Revision 1.12 2004/02/16 08:19:44 reinelt * i2c_sensors patch from Xavier * * Revision 1.11 2004/02/15 21:43:43 reinelt * T6963 driver nearly finished * framework for graphic displays done * i2c_sensors patch from Xavier * some more old generation files removed * * Revision 1.10 2004/02/14 12:07:27 nicowallmeier * minor bugfix * * Revision 1.9 2004/02/14 11:56:17 reinelt * M50530 driver ported * changed lots of 'char' to 'unsigned char' * * Revision 1.8 2004/02/14 10:09:50 reinelt * I2C Sensors for 2.4 kernels (/proc instead of /sysfs) * * Revision 1.7 2004/01/30 20:57:56 reinelt * HD44780 patch from Martin Hejl * dmalloc integrated * * Revision 1.6 2004/01/30 07:12:35 reinelt * HD44780 busy-flag support from Martin Hejl * loadavg() uClibc replacement from Martin Heyl * round() uClibc replacement from Martin Hejl * warning in i2c_sensors fixed * * Revision 1.5 2004/01/29 05:55:30 reinelt * check for /sys mounted * * Revision 1.4 2004/01/29 04:40:02 reinelt * every .c file includes "config.h" now * * Revision 1.3 2004/01/27 08:13:39 reinelt * ported PPP token to plugin_ppp * * Revision 1.2 2004/01/27 05:06:10 reinelt * i2c update from Xavier * * Revision 1.1 2004/01/10 17:36:56 reinelt * * I2C Sensors plugin from Xavier added * */ /* * exported functions: * * int plugin_init_i2c_sensors (void) * adds function i2c_sensors() to retrieve informations from * the i2c sensors via sysfs or procfs interface * * -- WARNING -- * This plugin should detect where your sensors are at startup. * If you can't get any token to work, ensure you don't get * an error message with "lcd4linux -Fvvv". * * If so, try to force the path to your sensors in the conf like this : * for sysfs: i2c_sensors-path '/sys/bus/i2c/devices/0-6000/' * for procfs: i2c_sensors-path '/proc/sys/dev/sensors/via686a-isa-6000' * /!\ these path are for my system, change the last dir according to yours */ /* * Available tokens : # represents an int from 1 to 3 (or more) * temp_input# -> temperature of sensor # (in °C) * temp_max# and temp_hyst# -> max and min of sensor # * in_input#, in_min# and in_max# -> voltages * fan_input# -> speed (in RPM) of fan # * fan_min# and fan_div# * * Tokens avaible only via sysfs if suported by your sensors: * curr_input#, curr_min# and curr_max# -> value of current (in amps) * pwm# * temp_crit# -> critical value of sensor # * vid -> cpu core voltage * and maybe others * (see /usr/src/linux/Documentation/i2c/sysfs-interface on linux 2.6) */ #include "config.h" #include #include #include #include #include #include #include #include "debug.h" #include "plugin.h" #include "cfg.h" #include "hash.h" #include "qprintf.h" #ifdef WITH_DMALLOC #include #endif static char *path = NULL; static HASH I2Csensors; static const char *procfs_tokens[4][3] = { {"temp_hyst", "temp_max", "temp_input"}, /* for temp# */ {"in_min", "in_max", "in_input"}, /* for in# */ {"fan_div1", "fan_div2", "fan_div3"}, /* for fan_div */ {"fan_min", "fan_input", ""} /* for fan# */ }; static int (*parse_i2c_sensors) (const char *key); /***********************************************\ * Parsing for new 2.6 kernels 'sysfs' interface * \***********************************************/ static int parse_i2c_sensors_sysfs(const char *key) { char val[32]; char buffer[32]; char file[64]; FILE *stream; strcpy(file, path); strcat(file, key); stream = fopen(file, "r"); if (stream == NULL) { error("i2c_sensors: fopen(%s) failed: %s", file, strerror(errno)); return -1; } fgets(buffer, sizeof(buffer), stream); fclose(stream); if (!buffer) { error("i2c_sensors: %s empty ?!", file); return -1; } /* now the formating stuff, depending on the file : */ /* Some values must be divided by 1000, the others */ /* are parsed directly (we just remove the \n). */ if (!strncmp(key, "temp", 4) || !strncmp(key, "curr", 4) || !strncmp(key, "in", 2) || !strncmp(key, "vid", 3)) { snprintf(val, sizeof(val), "%f", strtod(buffer, NULL) / 1000.0); } else { qprintf(val, sizeof(val), "%s", buffer); /* we supress this nasty \n at the end */ val[strlen(val) - 1] = '\0'; } hash_put(&I2Csensors, key, val); return 0; } /************************************************\ * Parsing for old 2.4 kernels 'procfs' interface * \************************************************/ static int parse_i2c_sensors_procfs(const char *key) { char file[64]; FILE *stream; char buffer[32]; char *value; char *running; int pos = 0; const char delim[3] = " \n"; char final_key[32]; const char *number = &key[strlen(key) - 1]; int tokens_index; /* debug("%s -> %s", key, number); */ strcpy(file, path); if (!strncmp(key, "temp_", 5)) { tokens_index = 0; strcat(file, "temp"); strcat(file, number); } else if (!strncmp(key, "in_", 3)) { tokens_index = 1; strcat(file, "in"); strcat(file, number); } else if (!strncmp(key, "fan_div", 7)) { tokens_index = 2; strcat(file, "fan_div"); number = ""; } else if (!strncmp(key, "fan_", 4)) { tokens_index = 3; strcat(file, "fan"); strcat(file, number); } else { return -1; } stream = fopen(file, "r"); if (stream == NULL) { error("i2c_sensors: fopen(%s) failed: %s", file, strerror(errno)); return -1; } fgets(buffer, sizeof(buffer), stream); fclose(stream); if (!buffer) { error("i2c_sensors: %s empty ?!", file); return -1; } running = strdupa(buffer); while (1) { value = strsep(&running, delim); /* debug("%s pos %i -> %s", file, pos , value); */ if (!value || !strcmp(value, "")) { /* debug("%s pos %i -> BREAK", file, pos); */ break; } else { qprintf(final_key, sizeof(final_key), "%s%s", procfs_tokens[tokens_index][pos], number); /* debug ("%s -> %s", final_key, value); */ hash_put(&I2Csensors, final_key, value); pos++; } } return 0; } /*****************************************\ * Common functions (path search and init) * \*****************************************/ static void my_i2c_sensors_path(const char *method) { struct dirent *dir; struct dirent *file; const char *base; char dname[64]; DIR *fd1; DIR *fd2; int done; if (!strcmp(method, "sysfs")) { base = "/sys/bus/i2c/devices/"; } else if (!strcmp(method, "procfs")) { base = "/proc/sys/dev/sensors/"; /*base="/sensors_2.4/"; // fake dir to test without rebooting 2.4 ;) */ } else { return; } fd1 = opendir(base); if (!fd1) { return; } while ((dir = readdir(fd1))) { /* Skip non-directories and '.' and '..' */ if ((dir->d_type != DT_DIR && dir->d_type != DT_LNK) || strcmp(dir->d_name, ".") == 0 || strcmp(dir->d_name, "..") == 0) { continue; } /* dname is the absolute path */ strcpy(dname, base); strcat(dname, dir->d_name); strcat(dname, "/"); fd2 = opendir(dname); done = 0; while ((file = readdir(fd2))) { /* FIXME : do all sensors have a temp_input1 ? */ if (!strcmp(file->d_name, "temp_input1") || !strcmp(file->d_name, "temp1_input") || !strcmp(file->d_name, "temp1")) { path = realloc(path, strlen(dname) + 1); strcpy(path, dname); done = 1; break; } } closedir(fd2); if (done) break; } closedir(fd1); } static int configure_i2c_sensors(void) { static int configured = 0; char *path_cfg; if (configured != 0) return configured; path_cfg = cfg_get(NULL, "i2c_sensors-path", ""); if (path_cfg == NULL || *path_cfg == '\0') { /* debug("No path to i2c sensors found in the conf, calling my_i2c_sensors_path()"); */ my_i2c_sensors_path("sysfs"); if (!path) my_i2c_sensors_path("procfs"); if (!path) { error("i2c_sensors: unable to autodetect i2c sensors!"); configured = -1; return configured; } debug("using i2c sensors at %s (autodetected)", path); } else { if (path_cfg[strlen(path_cfg) - 1] != '/') { /* the headless user forgot the trailing slash :/ */ error("i2c_sensors: please add a trailing slash to %s from %s", path_cfg, cfg_source()); path_cfg = realloc(path_cfg, strlen(path_cfg) + 2); strcat(path_cfg, "/"); } debug("using i2c sensors at %s (from %s)", path, cfg_source()); path = realloc(path, strlen(path_cfg) + 1); strcpy(path, path_cfg); } if (path_cfg) free(path_cfg); /* we activate the function only if there's a possibly path found */ if (strncmp(path, "/sys", 4) == 0) { parse_i2c_sensors = parse_i2c_sensors_sysfs; } else if (strncmp(path, "/proc", 5) == 0) { parse_i2c_sensors = parse_i2c_sensors_procfs; } else { error("i2c_sensors: unknown path %s, should start with /sys or /proc"); configured = -1; return configured; } hash_create(&I2Csensors); configured = 1; return configured; } void my_i2c_sensors(RESULT * result, RESULT * arg) { int age; char *key; char *val; if (configure_i2c_sensors() < 0) { SetResult(&result, R_STRING, "??"); return; } key = R2S(arg); age = hash_age(&I2Csensors, key); if (age < 0 || age > 250) { parse_i2c_sensors(key); } val = hash_get(&I2Csensors, key, NULL); if (val) { SetResult(&result, R_STRING, val); } else { SetResult(&result, R_STRING, "??"); } } int plugin_init_i2c_sensors(void) { AddFunction("i2c_sensors", 1, my_i2c_sensors); return 0; } void plugin_exit_i2c_sensors(void) { hash_destroy(&I2Csensors); } id='n295' href='#n295'>295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 
/* $Id$
 * $URL$
 *
 * new style driver for Crystalfontz display modules
 *
 * Copyright (C) 1999, 2000 Michael Reinelt <michael@reinelt.co.at>
 * Copyright (C) 2004 The LCD4Linux Team <lcd4linux-devel@users.sourceforge.net>
 *
 * This file is part of LCD4Linux.
 *
 * LCD4Linux 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 2, or (at your option)
 * any later version.
 *
 * LCD4Linux 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, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 */

/* 
 *
 * exported fuctions:
 *
 * struct DRIVER drv_Crystalfontz
 *
 */

#include "config.h"

#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <sys/time.h>

#include "debug.h"
#include "cfg.h"
#include "qprintf.h"
#include "thread.h"
#include "timer.h"
#include "plugin.h"
#include "widget.h"
#include "widget_text.h"
#include "widget_icon.h"
#include "widget_bar.h"
#include "widget_keypad.h"
#include "drv.h"
#include "drv_generic_text.h"
#include "drv_generic_gpio.h"
#include "drv_generic_serial.h"
#include "drv_generic_keypad.h"


static char Name[] = "Crystalfontz";

static int Model;
static int Protocol;
static int Payload;

/* ring buffer for bytes received from the display */
static unsigned char RingBuffer[256];
static unsigned int RingRPos = 0;
static unsigned int RingWPos = 0;

/* packet from the display */
struct {
    unsigned char type;
    unsigned char code;
    unsigned char size;
    unsigned char data[16 + 1];	/* trailing '\0' */
} Packet;

/* Line Buffer for 633 displays */
static unsigned char Line[2 * 16];

/* Fan RPM */
static double Fan_RPM[4] = { 0.0, };

/* Temperature sensors */
static double Temperature[32] = { 0.0, };


typedef struct {
    int type;
    char *name;
    int rows;
    int cols;
    int gpis;
    int gpos;
    int protocol;
    int payload;
} MODEL;

/* Fixme #1: number of GPI's & GPO's should be verified */
/* Fixme #2: protocol should be verified */
/* Fixme #3: number of keys on the keypad should be verified */

static MODEL Models[] = {
    {626, "626", 2, 16, 0, 0, 1, 0},
    {631, "631", 2, 20, 4, 0, 3, 22},
    {632, "632", 2, 16, 0, 0, 1, 0},
    {633, "633", 2, 16, 4, 4, 2, 18},
    {634, "634", 4, 20, 0, 0, 1, 0},
    {635, "635", 4, 20, 4, 12, 3, 22},
    {636, "636", 2, 16, 0, 0, 1, 0},
    {-1, "Unknown", -1, -1, 0, 0, 0, 0}
};


/****************************************/
/***  hardware dependant functions    ***/
/****************************************/

/* x^0 + x^5 + x^12 */
#define CRCPOLY 0x8408

static unsigned short CRC(const unsigned char *p, size_t len, unsigned short seed)
{
    int i;
    while (len--) {
	seed ^= *p++;
	for (i = 0; i < 8; i++)
	    seed = (seed >> 1) ^ ((seed & 1) ? CRCPOLY : 0);
    }
    return ~seed;
}

static unsigned char LSB(const unsigned short word)
{
    return word & 0xff;
}

static unsigned char MSB(const unsigned short word)
{
    return word >> 8;
}


static unsigned char byte(unsigned int pos)
{
    pos += RingRPos;
    if (pos >= sizeof(RingBuffer))
	pos -= sizeof(RingBuffer);
    return RingBuffer[pos];
}


static void drv_CF_process_packet(void)
{

    switch (Packet.type) {

    case 0x02:

	/* async response from display to host */
	switch (Packet.code) {

	case 0x00:
	    /* Key Activity */
	    debug("Key Activity: %d", Packet.data[0]);
	    drv_generic_keypad_press(Packet.data[0]);
	    break;

	case 0x01:
	    /* Fan Speed Report */
	    if (Packet.data[1] == 0xff) {
		Fan_RPM[Packet.data[0]] = -1.0;
	    } else if (Packet.data[1] < 4) {
		Fan_RPM[Packet.data[0]] = 0.0;
	    } else {
		Fan_RPM[Packet.data[0]] =
		    (double) 27692308L *(Packet.data[1] - 3) / (Packet.data[2] + 256 * Packet.data[3]);
	    }
	    break;

	case 0x02:
	    /* Temperature Sensor Report */
	    switch (Packet.data[3]) {
	    case 0:
		error("%s: 1-Wire device #%d: CRC error", Name, Packet.data[0]);
		break;
	    case 1:
	    case 2:
		Temperature[Packet.data[0]] = (Packet.data[1] + 256 * Packet.data[2]) / 16.0;
		break;
	    default:
		error("%s: 1-Wire device #%d: unknown CRC status %d", Name, Packet.data[0], Packet.data[3]);
		break;
	    }
	    break;

	default:
	    /* this should not happen */
	    error("%s: unexpected response type=0x%02x code=0x%02x size=%d", Name, Packet.type, Packet.code,
		  Packet.size);
	    break;
	}

	break;

    case 0x03:
	/* error response from display to host */
	error("%s: error response type=0x%02x code=0x%02x size=%d", Name, Packet.type, Packet.code, Packet.size);
	break;

    default:
	/* these should not happen: */
	/* type 0x00: command from host to display: should never come back */
	/* type 0x01: command response from display to host: are processed within send() */
	error("%s: unexpected packet type=0x%02x code=0x%02x size=%d", Name, Packet.type, Packet.code, Packet.size);
	break;
    }

}


static int drv_CF_poll(void)
{
    /* read into RingBuffer */
    while (1) {
	char buffer[32];
	int num, n;
	num = drv_generic_serial_poll(buffer, sizeof(buffer));
	if (num <= 0)
	    break;
	/* put result into RingBuffer */
	for (n = 0; n < num; n++) {
	    RingBuffer[RingWPos++] = (unsigned char) buffer[n];
	    if (RingWPos >= sizeof(RingBuffer))
		RingWPos = 0;
	}
    }

    /* process RingBuffer */
    while (1) {
	unsigned char buffer[32];
	int n, num, size;
	unsigned short crc;
	/* packet size */
	num = RingWPos - RingRPos;
	if (num < 0)
	    num += sizeof(RingBuffer);
	/* minimum packet size=4 */
	if (num < 4)
	    return 0;
	/* valid response types: 01xxxxx 10.. 11.. */
	/* therefore: 00xxxxxx is invalid */
	if (byte(0) >> 6 == 0)
	    goto GARBAGE;
	/* command length */
	size = byte(1);
	/* valid command length is 0 to 16 */
	if (size > 16)
	    goto GARBAGE;
	/* all bytes available? */
	if (num < size + 4)
	    return 0;
	/* check CRC */
	for (n = 0; n < size + 4; n++)
	    buffer[n] = byte(n);
	crc = CRC(buffer, size + 2, 0xffff);
	if (LSB(crc) != buffer[size + 2])
	    goto GARBAGE;
	if (MSB(crc) != buffer[size + 3])
	    goto GARBAGE;
	/* process packet */
	Packet.type = buffer[0] >> 6;
	Packet.code = buffer[0] & 0x3f;
	Packet.size = size;
	memcpy(Packet.data, buffer + 2, size);
	Packet.data[size] = '\0';	/* trailing zero */
	/* increment read pointer */
	RingRPos += size + 4;
	if (RingRPos >= sizeof(RingBuffer))
	    RingRPos -= sizeof(RingBuffer);
	/* a packet arrived */
	return 1;
      GARBAGE:
	debug("dropping garbage byte %02x", byte(0));
	RingRPos++;
	if (RingRPos >= sizeof(RingBuffer))
	    RingRPos = 0;
	continue;
    }

    /* not reached */
    return 0;
}


static void drv_CF_timer(void __attribute__ ((unused)) * notused)
{
    while (drv_CF_poll()) {
	drv_CF_process_packet();
    }
}


static void drv_CF_send(const unsigned char cmd, const unsigned char len, const unsigned char *data)
{
    /* 1 cmd + 1 len + 22 payload + 2 crc = 26 */
    unsigned char buffer[26];
    unsigned short crc;
    struct timeval now, end;

    if (len > Payload) {
	error("%s: internal error: packet length %d exceeds payload size %d", Name, len, Payload);
	return;
    }

    buffer[0] = cmd;
    buffer[1] = len;
    memcpy(buffer + 2, data, len);
    crc = CRC(buffer, len + 2, 0xffff);
    buffer[len + 2] = LSB(crc);
    buffer[len + 3] = MSB(crc);

    drv_generic_serial_write((char *) buffer, len + 4);

    /* wait for acknowledge packet */
    gettimeofday(&now, NULL);
    while (1) {
	/* delay 1 msec */
	usleep(1 * 1000);
	if (drv_CF_poll()) {
	    if (Packet.type == 0x01 && Packet.code == cmd) {
		/* this is the ack we're waiting for */
		if (0) {
		    gettimeofday(&end, NULL);
		    debug("%s: ACK after %ld usec", Name,
			  1000000 * (end.tv_sec - now.tv_sec) + end.tv_usec - now.tv_usec);
		}
		break;
	    } else {
		/* some other (maybe async) packet, just process it */
		drv_CF_process_packet();
	    }
	}
	gettimeofday(&end, NULL);
	/* don't wait more than 250 msec */
	if ((1000000 * (end.tv_sec - now.tv_sec) + end.tv_usec - now.tv_usec) > 250 * 1000) {
	    error("%s: timeout waiting for response to cmd 0x%02x", Name, cmd);
	    break;
	}
    }
}


/* check http://www.crystalfontz.com/products/634/cgrom.html */
/* HINT: the input should using the ISO-8859-1 charset */
void convertToCgrom2(char *str)
{
    unsigned int i;
    for (i = 0; i < strlen(str); i++) {
	switch ((unsigned char) str[i]) {
	case 0x5d:		/* ] */
	    str[i] = 252;
	    break;
	case 0x5b:		/* [ */
	    str[i] = 250;
	    break;
	case 0x24:		/* $ */
	    str[i] = 162;
	    break;
	case 0x40:		/* @ */
	    str[i] = 160;
	    break;
	case 0x5c:		/* \ */
	    str[i] = 251;
	    break;
	case 0x7b:		/* { */
	    str[i] = 253;
	    break;
	case 0x7d:		/* } */
	    str[i] = 255;
	    break;
	case 0x7c:
	    str[i] = 254;	/* pipe */
	    break;
	case 0x27:
	case 0x60:
	case 0xB4:
	    str[i] = 39;	/* ' */
	    break;
	case 0xe8:
	    str[i] = 164;	/* french e */
	    break;
	case 0xe9:
	    str[i] = 165;	/* french e */
	    break;
	case 0xc8:
	    str[i] = 197;	/* french E */
	    break;
	case 0xc9:
	    str[i] = 207;	/* french E */
	    break;

	case 0xe4:
	    str[i] = 123;	/* small german ae */
	    break;
	case 0xc4:
	    str[i] = 91;	/* big german ae */
	    break;
	case 0xf6:
	    str[i] = 124;	/* small german oe */
	    break;
	case 0xd6:
	    str[i] = 92;	/* big german oe */
	    break;
	case 0xfc:
	    str[i] = 126;	/* small german ue */
	    break;
	case 0xdc:
	    str[i] = 94;	/* big german ue */
	    break;
	case 0x5e:		/* ^ */
	    str[i] = 253;
	    break;
	case 0x5f:		/* _ */
	    str[i] = 254;
	    break;
	default:
	    break;
	}
    }
}


static void drv_CF_write1(const int row, const int col, const char *data, const int len)
{
    char cmd[3] = "\021xy";	/* set cursor position */

    if (row == 0 && col == 0) {
	drv_generic_serial_write("\001", 1);	/* cursor home */
    } else {
	cmd[1] = (char) col;
	cmd[2] = (char) row;
	drv_generic_serial_write(cmd, 3);
    }

    /* Model 634 and 632 use another ROM */
    if (Model == 4 || Model == 2) {
	convertToCgrom2((char *) data);
    }

    drv_generic_serial_write(data, len);
}


static void drv_CF_write2(const int row, const int col, const char *data, const int len)
{
    int l = len;

    /* limit length */
    if (col + l > 16)
	l = 16 - col;
    if (l < 0)
	l = 0;

    /* sanity check */
    if (row >= 2 || col + l > 16) {
	error("%s: internal error: write outside linebuffer bounds!", Name);
	return;
    }
    memcpy(Line + 16 * row + col, data, l);
    drv_CF_send(7 + row, 16, (unsigned char *) (Line + 16 * row));
}


static void drv_CF_write3(const int row, const int col, const char *data, const int len)
{
    int l = len;
    unsigned char cmd[23];

    /* limit length */
    if (col + l > DCOLS)
	l = DCOLS - col;
    if (l < 0)
	l = 0;

    /* sanity check */
    if (row >= DROWS || col + l > DCOLS) {
	error("%s: internal error: write outside display bounds!", Name);
	return;
    }

    cmd[0] = col;
    cmd[1] = row;
    memcpy(cmd + 2, data, l);

    drv_CF_send(31, l + 2, cmd);
}


static void drv_CF_defchar1(const int ascii, const unsigned char *matrix)
{
    int i;
    char cmd[10] = "\031n";	/* set custom char bitmap */

    /* user-defineable chars start at 128, but are defined at 0 */
    cmd[1] = (char) (ascii - CHAR0);
    for (i = 0; i < 8; i++) {
	cmd[i + 2] = matrix[i] & 0x3f;
    }
    drv_generic_serial_write(cmd, 10);
}


static void drv_CF_defchar23(const int ascii, const unsigned char *matrix)
{
    int i;
    unsigned char buffer[9];

    /* user-defineable chars start at 128, but are defined at 0 */
    buffer[0] = (char) (ascii - CHAR0);

    /* clear bit 6 and 7 of the bitmap (blinking) */
    for (i = 0; i < 8; i++) {
	buffer[i + 1] = matrix[i] & 0x3f;
    }

    drv_CF_send(9, 9, buffer);
}


static int drv_CF_contrast(int contrast)
{
    static unsigned char Contrast = 0;
    char buffer[2];

    /* -1 is used to query the current contrast */
    if (contrast == -1)
	return Contrast;

    if (contrast < 0)
	contrast = 0;
    if (contrast > 255)
	contrast = 255;
    Contrast = contrast;

    switch (Protocol) {

    case 1:
	/* contrast range 0 to 100 */
	if (Contrast > 100)
	    Contrast = 100;
	buffer[0] = 15;		/* Set LCD Contrast */
	buffer[1] = Contrast;
	drv_generic_serial_write(buffer, 2);
	break;

    case 2:
	/* contrast range 0 to 50 */
	if (Contrast > 50)
	    Contrast = 50;
	drv_CF_send(13, 1, &Contrast);
	break;

    case 3:
	/* contrast range 0 to 255 */
	drv_CF_send(13, 1, &Contrast);
	break;
    }

    return Contrast;
}


static int drv_CF_backlight(int backlight)
{
    static unsigned char Backlight = 0;
    char buffer[2];

    /* -1 is used to query the current backlight */
    if (backlight == -1)
	return Backlight;

    if (backlight < 0)
	backlight = 0;
    if (backlight > 100)
	backlight = 100;
    Backlight = backlight;

    switch (Protocol) {

    case 1:
	buffer[0] = 14;		/* Set LCD Backlight */
	buffer[1] = Backlight;
	drv_generic_serial_write(buffer, 2);
	break;

    case 2:
    case 3:
	drv_CF_send(14, 1, &Backlight);
	break;
    }

    return Backlight;
}


static int drv_CF_keypad(const int num)
{
    int val = 0;

    switch (Protocol) {
    case 1:
    case 2:
	break;
    case 3:
	if ((num < 8) || ((num > 12) && (num < 17)))
	    val = WIDGET_KEY_PRESSED;
	else
	    val = WIDGET_KEY_RELEASED;
	switch (num) {
	case 1:
	case 7:
	    val += WIDGET_KEY_UP;
	    break;
	case 2:
	case 8:
	    val += WIDGET_KEY_DOWN;
	    break;
	case 3:
	case 9:
	    val += WIDGET_KEY_LEFT;
	    break;
	case 4:
	case 10:
	    val += WIDGET_KEY_RIGHT;
	    break;
	case 5:
	case 11:
	    val += WIDGET_KEY_CONFIRM;
	    break;
	case 6:
	case 12:
	    val += WIDGET_KEY_CANCEL;
	    break;

	    /* added for 631, too lazy to make new WIDGET_KEY defines */
	case 13:
	case 17:
	    val += WIDGET_KEY_UP;	/* really UPLEFT */
	    break;
	case 14:
	case 18:
	    val += WIDGET_KEY_RIGHT;	/* really UPRIGHT */
	    break;
	case 15:
	case 19:
	    val += WIDGET_KEY_LEFT;	/* really DOWNLEFT */
	    break;
	case 16:
	case 20:
	    val += WIDGET_KEY_DOWN;	/* really DOWNRIGHT */
	    break;
	}
	break;
    }

    return val;
}


static int drv_CF_GPI(const int num)
{
    if (num < 0 || num > 3) {
	return 0;
    }
    return Fan_RPM[num];
}


static int drv_CF_GPO(const int num, const int val)
{
    static unsigned char PWM2[4] = { 0, 0, 0, 0 };
    static unsigned char PWM3[2];

    int v = val;

    if (v < 0)
	v = 0;
    if (v > 100)
	v = 100;

    switch (Protocol) {
    case 2:
	PWM2[num] = v;
	drv_CF_send(17, 4, PWM2);
	break;
    case 3:
	PWM3[0] = num + 1;
	PWM3[1] = v;
	drv_CF_send(34, 2, PWM3);
	break;
    }

    return v;
}


static int drv_CF_autodetect(void)
{
    int m;

    /* only autodetect newer displays */
    if (Protocol < 2)
	return -1;

    /* read display type */
    drv_CF_send(1, 0, NULL);

    /* send() did already wait for response packet */
    if (Packet.type == 0x01 && Packet.code == 0x01) {
	char t[7], c;
	float h, v;
	info("%s: display identifies itself as '%s'", Name, Packet.data);
	if (sscanf((char *) Packet.data, "%6s:h%f,%c%f", t, &h, &c, &v) != 4) {
	    error("%s: error parsing display identification string", Name);
	    return -1;
	}
	info("%s: display type '%s', hardware version %3.1f, firmware version %c%3.1f", Name, t, h, c, v);
	if (strncmp(t, "CFA", 3) == 0) {
	    for (m = 0; Models[m].type != -1; m++) {
		/* omit the 'CFA' */
		if (strcasecmp(Models[m].name, t + 3) == 0)
		    return m;
	    }
	}
	error("%s: display type '%s' may be not supported!", Name, t);
	return -1;
    }

    error("%s: display detection failed!", Name);

    return -1;
}


static char *drv_CF_print_ROM(void)
{
    static char buffer[17];

    snprintf(buffer, sizeof(buffer), "0x%02x%02x%02x%02x%02x%02x%02x%02x",
	     Packet.data[1], Packet.data[2], Packet.data[3], Packet.data[4], Packet.data[5], Packet.data[6],
	     Packet.data[7], Packet.data[8]);

    return buffer;
}


static int drv_CF_scan_DOW(unsigned char index)
{
    int i;

    /* Read DOW Device Information */
    drv_CF_send(18, 1, &index);

    i = 0;
    while (1) {
	/* wait 10 msec */
	usleep(10 * 1000);
	/* packet available? */
	if (drv_CF_poll()) {
	    /* DOW Device Info */
	    if (Packet.type == 0x01 && Packet.code == 0x12) {
		switch (Packet.data[1]) {
		case 0x00:
		    /* no device found */
		    return 0;
		case 0x22:
		    info("%s: 1-Wire device #%d: DS1822 temperature sensor found at %s", Name, Packet.data[0],
			 drv_CF_print_ROM());
		    return 1;
		case 0x28:
		    info("%s: 1-Wire device #%d: DS18B20 temperature sensor found at %s", Name, Packet.data[0],
			 drv_CF_print_ROM());
		    return 1;
		default:
		    info("%s: 1-Wire device #%d: unknown device found at %s", Name, Packet.data[0], drv_CF_print_ROM());
		    return 0;
		}
	    } else {
		drv_CF_process_packet();
	    }
	}
	/* wait no longer than 300 msec */
	if (++i > 30) {
	    error("%s: 1-Wire device #%d detection timed out", Name, index);
	    return -1;
	}
    }

    /* not reached */
    return -1;
}


/* clear display */
static void drv_CF_clear(void)
{
    switch (Protocol) {
    case 1:
	drv_generic_serial_write("\014", 1);
	break;
    case 2:
    case 3:
	drv_CF_send(6, 0, NULL);
	break;
    }
}


/* init sequences for 626, 632, 634, 636  */
static void drv_CF_start_1(void)
{
    drv_generic_serial_write("\014", 1);	/* Form Feed (Clear Display) */
    drv_generic_serial_write("\004", 1);	/* hide cursor */
    drv_generic_serial_write("\024", 1);	/* scroll off */
    drv_generic_serial_write("\030", 1);	/* wrap off */
}


/* init sequences for 633 */
static void drv_CF_start_2(void)
{
    int i;
    unsigned long mask;
    unsigned char buffer[4];

    /* Clear Display */
    drv_CF_send(6, 0, NULL);

    /* Set LCD Cursor Style */
    buffer[0] = 0;
    drv_CF_send(12, 1, buffer);

    /* enable Fan Reporting */
    buffer[0] = 15;
    drv_CF_send(16, 1, buffer);

    /* Set Fan Power to 100% */
    buffer[0] = buffer[1] = buffer[2] = buffer[3] = 100;
    drv_CF_send(17, 4, buffer);

    /* Read DOW Device Information */
    mask = 0;
    for (i = 0; i < 32; i++) {
	if (drv_CF_scan_DOW(i) == 1) {
	    mask |= 1 << i;
	}
    }

    /* enable Temperature Reporting */
    buffer[0] = mask & 0xff;
    buffer[1] = (mask >> 8) & 0xff;
    buffer[2] = (mask >> 16) & 0xff;
    buffer[3] = (mask >> 24) & 0xff;
    drv_CF_send(19, 4, buffer);
}


/* init sequences for 631 */
static void drv_CF_start_3(void)
{
    unsigned char buffer[1];

    /* Clear Display */
    drv_CF_send(6, 0, NULL);

    /* Set LCD Cursor Style */
    buffer[0] = 0;
    drv_CF_send(12, 1, buffer);

}


static int drv_CF_start(const char *section)
{
    int i;
    char *model;

    model = cfg_get(section, "Model", NULL);
    if (model != NULL && *model != '\0') {
	for (i = 0; Models[i].type != -1; i++) {
	    if (strcasecmp(Models[i].name, model) == 0)
		break;
	}
	if (Models[i].type == -1) {
	    error("%s: %s.Model '%s' is unknown from %s", Name, section, model, cfg_source());
	    return -1;
	}
	Model = i;
	Protocol = Models[Model].protocol;
	info("%s: using model '%s'", Name, Models[Model].name);
    } else {
	Model = -1;
	Protocol = 2;		/*auto-detect only newer displays */
	info("%s: no '%s.Model' entry from %s, auto-detecting", Name, section, cfg_source());
    }

    /* open serial port */
    if (drv_generic_serial_open(section, Name, 0) < 0)
	return -1;

    /* Fixme: why such a large delay? */
    usleep(350 * 1000);

    /* display autodetection */
    i = drv_CF_autodetect();
    if (Model == -1)
	Model = i;
    if (Model == -1) {
	error("%s: auto-detection failed, please specify a '%s.Model' entry in %s", Name, section, cfg_source());
	return -1;
    }
    if (i != -1 && Model != i) {
	error("%s: %s.Model '%s' from %s does not match detected model '%s'", Name, section, model, cfg_source(),
	      Models[i].name);
	return -1;
    }

    /* initialize global variables */
    DROWS = Models[Model].rows;
    DCOLS = Models[Model].cols;
    GPIS = Models[Model].gpis;
    GPOS = Models[Model].gpos;
    Protocol = Models[Model].protocol;
    Payload = Models[Model].payload;


    switch (Protocol) {

    case 1:
	drv_CF_start_1();
	break;

    case 2:
	/* regularly process display answers */
	/* Fixme: make 100msec configurable */
	timer_add(drv_CF_timer, NULL, 100, 0);
	drv_CF_start_2();
	/* clear 633 linebuffer */
	memset(Line, ' ', sizeof(Line));
	break;

    case 3:
	/* regularly process display answers */
	/* Fixme: make 100msec configurable */
	timer_add(drv_CF_timer, NULL, 100, 0);
	drv_CF_start_3();
	break;
    }

    /* set contrast */
    if (cfg_number(section, "Contrast", 0, 0, 255, &i) > 0) {
	drv_CF_contrast(i);
    }

    /* set backlight */
    if (cfg_number(section, "Backlight", 0, 0, 100, &i) > 0) {
	drv_CF_backlight(i);
    }

    return 0;
}


/****************************************/
/***            plugins               ***/
/****************************************/


static void plugin_contrast(RESULT * result, const int argc, RESULT * argv[])
{
    double contrast;

    switch (argc) {
    case 0:
	contrast = drv_CF_contrast(-1);
	SetResult(&result, R_NUMBER, &contrast);
	break;
    case 1:
	contrast = drv_CF_contrast(R2N(argv[0]));
	SetResult(&result, R_NUMBER, &contrast);
	break;
    default:
	error("%s.contrast(): wrong number of parameters", Name);
	SetResult(&result, R_STRING, "");
    }
}


static void plugin_backlight(RESULT * result, const int argc, RESULT * argv[])
{
    double backlight;

    switch (argc) {
    case 0:
	backlight = drv_CF_backlight(-1);
	SetResult(&result, R_NUMBER, &backlight);
	break;
    case 1:
	backlight = drv_CF_backlight(R2N(argv[0]));
	SetResult(&result, R_NUMBER, &backlight);
	break;
    default:
	error("%s.backlight(): wrong number of parameters", Name);
	SetResult(&result, R_STRING, "");
    }
}


/* Fixme: other plugins for Fans, Temperature sensors, ... */



/****************************************/
/***        widget callbacks          ***/
/****************************************/

/* using drv_generic_text_draw(W) */
/* using drv_generic_text_icon_draw(W) */
/* using drv_generic_text_bar_draw(W) */
/* using drv_generic_gpio_draw(W) */
/* using drv_generic_keypad_draw(W) */


/****************************************/
/***        exported functions        ***/
/****************************************/


/* list models */
int drv_CF_list(void)
{
    int i;

    for (i = 0; Models[i].type != -1; i++) {
	printf("%s ", Models[i].name);
    }
    return 0;
}


/* initialize driver & display */
int drv_CF_init(const char *section, const int quiet)
{
    WIDGET_CLASS wc;
    int ret;

    info("%s: %s", Name, "$Rev$");

    /* start display */
    if ((ret = drv_CF_start(section)) != 0) {
	return ret;
    }

    /* display preferences */
    XRES = 6;			/* pixel width of one char  */
    YRES = 8;			/* pixel height of one char  */
    CHARS = 8;			/* number of user-defineable characters */

    /* real worker functions */
    switch (Protocol) {
    case 1:
	CHAR0 = 128;		/* ASCII of first user-defineable char */
	GOTO_COST = 3;		/* number of bytes a goto command requires */
	drv_generic_text_real_write = drv_CF_write1;
	drv_generic_text_real_defchar = drv_CF_defchar1;
	break;
    case 2:
	CHAR0 = 0;		/* ASCII of first user-defineable char */
	GOTO_COST = -1;		/* there is no goto on 633 */
	drv_generic_text_real_write = drv_CF_write2;
	drv_generic_text_real_defchar = drv_CF_defchar23;
	drv_generic_gpio_real_get = drv_CF_GPI;
	drv_generic_gpio_real_set = drv_CF_GPO;
	break;
    case 3:
	CHAR0 = 0;		/* ASCII of first user-defineable char */
	GOTO_COST = 3;		/* number of bytes a goto command requires */
	drv_generic_text_real_write = drv_CF_write3;
	drv_generic_text_real_defchar = drv_CF_defchar23;
	drv_generic_gpio_real_get = drv_CF_GPI;
	drv_generic_gpio_real_set = drv_CF_GPO;
	drv_generic_keypad_real_press = drv_CF_keypad;
	break;
    }

    if (!quiet) {
	char buffer[40];
	qprintf(buffer, sizeof(buffer), "%s %s", Name, Models[Model].name);
	if (drv_generic_text_greet(buffer, "www.crystalfontz.com")) {
	    sleep(3);
	    drv_CF_clear();
	}
    }

    /* initialize generic text driver */
    if ((ret = drv_generic_text_init(section, Name)) != 0)
	return ret;

    /* initialize generic icon driver */
    if ((ret = drv_generic_text_icon_init()) != 0)
	return ret;

    /* initialize generic bar driver */
    if ((ret = drv_generic_text_bar_init(0)) != 0)
	return ret;

    /* add fixed chars to the bar driver */
    drv_generic_text_bar_add_segment(0, 0, 255, 32);	/* ASCII 32 = blank */
    if (Protocol == 2)
	drv_generic_text_bar_add_segment(255, 255, 255, 255);	/* ASCII 255 = block */

    /* initialize generic GPIO driver */
    if ((ret = drv_generic_gpio_init(section, Name)) != 0)
	return ret;

    /* initialize generic key pad driver */
    if ((ret = drv_generic_keypad_init(section, Name)) != 0)
	return ret;

    /* register text widget */
    wc = Widget_Text;
    wc.draw = drv_generic_text_draw;
    widget_register(&wc);

    /* register icon widget */
    wc = Widget_Icon;
    wc.draw = drv_generic_text_icon_draw;
    widget_register(&wc);

    /* register bar widget */
    wc = Widget_Bar;
    wc.draw = drv_generic_text_bar_draw;
    widget_register(&wc);

    /* register plugins */
    AddFunction("LCD::contrast", -1, plugin_contrast);
    AddFunction("LCD::backlight", -1, plugin_backlight);

    return 0;
}


/* close driver & display */
int drv_CF_quit(const int quiet)
{

    info("%s: shutting down display.", Name);

    drv_generic_text_quit();
    drv_generic_gpio_quit();
    drv_generic_keypad_quit();

    /* clear display */
    drv_CF_clear();

    /* say goodbye... */
    if (!quiet) {
	drv_generic_text_greet("goodbye!", NULL);
    }

    drv_generic_serial_close();

    return (0);
}


DRIVER drv_Crystalfontz = {
    .name = Name,
    .list = drv_CF_list,
    .init = drv_CF_init,
    .quit = drv_CF_quit,
};