1 /*- 2 * Copyright (c) 1997 Nicolas Souchu 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 * 26 * $Id: ppb_1284.c,v 1.1 1997/08/16 14:05:32 msmith Exp $ 27 * 28 */ 29 #include <sys/param.h> 30 #include <sys/systm.h> 31 32 #include <machine/clock.h> 33 34 #include <dev/ppbus/ppbconf.h> 35 #include <dev/ppbus/ppb_1284.h> 36 37 /* 38 * nibble_1284_wait() 39 * 40 * Wait for the peripherial up to 40ms 41 */ 42 int 43 nibble_1284_wait(struct ppb_device *dev, char mask, char status) 44 { 45 int i; 46 47 return (ppb_poll_device(dev, 4, mask, status, PPB_NOINTR)); 48 } 49 50 #define nibble2char(s) (((s & ~nACK) >> 3) | (~s & nBUSY) >> 4) 51 52 /* 53 * nibble_1284_inbyte() 54 * 55 * Read data in NIBBLE mode 56 */ 57 int 58 nibble_1284_inbyte(struct ppb_device *dev, char *buffer) 59 { 60 char nibble[2], r; 61 int i, error; 62 63 r = ppb_rctr(dev); 64 65 for (i = 0; i < 2; i++) { 66 /* ready to take data (nAUTO low) */ 67 ppb_wctr(dev, r | AUTOFEED); 68 69 if ((error = nibble_1284_wait(dev, nACK, 0))) { 70 ppb_wctr(dev, r); 71 return (error); 72 } 73 74 /* read nibble */ 75 nibble[i] = ppb_rstr(dev); 76 77 #ifdef DEBUG_1284 78 printf("nibble_1284_inbyte: nibble[%d]=0x%x\n", i, nibble[i]); 79 #endif 80 81 /* ack, not ready for another nibble */ 82 ppb_wctr(dev, r & ~AUTOFEED); 83 84 /* wait ack from peripherial */ 85 if ((error = nibble_1284_wait(dev, nACK, nACK))) { 86 ppb_wctr(dev, r); 87 return (error); 88 } 89 } 90 91 *buffer = ((nibble2char(nibble[1]) << 4) & 0xf0) | 92 (nibble2char(nibble[0]) & 0x0f); 93 94 #ifdef DEBUG_1284 95 printf("nibble_1284_inbyte: byte=0x%x\n", *buffer); 96 #endif 97 98 return (0); 99 } 100 101 /* 102 * nibble_1284_sync() 103 */ 104 void 105 nibble_1284_sync(struct ppb_device *dev) 106 { 107 char ctr; 108 109 ctr = ppb_rctr(dev); 110 111 ppb_wctr(dev, (ctr & ~AUTOFEED) | SELECTIN); 112 if (nibble_1284_wait(dev, nACK, 0)) 113 return; 114 115 ppb_wctr(dev, ctr | AUTOFEED); 116 nibble_1284_wait(dev, nACK, nACK); 117 118 ppb_wctr(dev, (ctr & ~AUTOFEED) | SELECTIN); 119 120 return; 121 } 122 123 /* 124 * nibble_1284_mode() 125 * 126 * Normal nibble mode or request device id mode (see ppb_1284.h) 127 */ 128 int 129 nibble_1284_mode(struct ppb_device *dev, int mode) 130 { 131 char ctrl; 132 int error; 133 134 ctrl = ppb_rctr(dev); 135 136 ppb_wdtr(dev, mode); 137 DELAY(5); 138 139 ppb_wctr(dev, (ctrl & ~SELECTIN) | AUTOFEED); 140 if ((error = nibble_1284_wait(dev, nACK | ERROR | SELECT | nFAULT, 141 ERROR | SELECT | nFAULT))) { 142 ppb_wctr(dev, ctrl); 143 return (error); 144 } 145 146 ppb_wctr(dev, ppb_rctr(dev) | STROBE); 147 DELAY(5); 148 149 ppb_wctr(dev, ppb_rctr(dev) & ~STROBE); 150 DELAY(5); 151 152 ppb_wctr(dev, ppb_rctr(dev) & ~AUTOFEED); 153 154 return (0); 155 } 156