1 /* $NetBSD: lcdkp_subr.c,v 1.6 2009/03/14 15:36:17 dsl Exp $ */ 2 3 /* 4 * Copyright (c) 2002 Dennis I. Chernoivanov 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. The name of the author may not be used to endorse or promote products 16 * derived from this software without specific prior written permission 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 19 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 20 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 21 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 22 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 23 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 24 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 25 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 27 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 28 */ 29 30 /* 31 * Subroutines for simple one-port keypad. 32 */ 33 34 #include <sys/cdefs.h> 35 __KERNEL_RCSID(0, "$NetBSD: lcdkp_subr.c,v 1.6 2009/03/14 15:36:17 dsl Exp $"); 36 37 #include <sys/param.h> 38 #include <sys/systm.h> 39 #include <sys/proc.h> 40 #include <sys/conf.h> 41 #include <sys/kernel.h> 42 #include <sys/types.h> 43 44 #include <machine/autoconf.h> 45 #include <sys/intr.h> 46 #include <sys/bus.h> 47 48 #include <dev/ic/lcdkp_subr.h> 49 50 #define HD_POLL_RATE (hz / 10) 51 52 static int lcdkp_poll(struct lcdkp_chip *); 53 static u_char lcdkp_scan(struct lcdkp_chip *, u_int8_t *); 54 55 /* 56 * Initialization. 57 */ 58 void 59 lcdkp_attach_subr(struct lcdkp_chip *sc) 60 { 61 sc->sc_flags = 0x0; 62 lcdkp_lock_init(sc); 63 } 64 65 /* 66 * Scan whether input is pending, don't block if not. 67 */ 68 int 69 lcdkp_scankey(struct lcdkp_chip *sc) 70 { 71 int ret; 72 73 if ((sc->sc_knum == 0) || (sc->sc_kpad == NULL)) 74 return 0; 75 76 lcdkp_lock(sc); 77 if (!(sc->sc_flags & LCDKP_HAS_BUF)) { 78 u_int8_t b; 79 if (lcdkp_scan(sc, &b) != 0) { 80 sc->sc_buf = b; 81 sc->sc_flags |= LCDKP_HAS_BUF; 82 } 83 } 84 ret = (sc->sc_flags & LCDKP_HAS_BUF); 85 lcdkp_unlock(sc); 86 87 return ret; 88 } 89 90 /* 91 * Read new key code, block if needed. 92 */ 93 int 94 lcdkp_readkey(struct lcdkp_chip *sc, u_int8_t *result) 95 { 96 int error; 97 98 if ((sc->sc_knum == 0) || (sc->sc_kpad == NULL)) 99 return EIO; 100 101 lcdkp_lock(sc); 102 if ( (error = lcdkp_poll(sc)) == 0) { 103 *result = sc->sc_buf; 104 sc->sc_flags &= ~LCDKP_HAS_BUF; 105 } 106 lcdkp_unlock(sc); 107 108 return 0; 109 } 110 111 /* 112 * Scan the keypad and translate the input. 113 */ 114 static u_char 115 lcdkp_scan(struct lcdkp_chip *sc, u_int8_t *b) 116 { 117 u_int8_t i; 118 u_int8_t c; 119 120 c = lcdkp_dr_read(sc); 121 for (i = 0; i < sc->sc_knum; i++) { 122 if (sc->sc_kpad[i].x_keycode == c) { 123 *b = sc->sc_kpad[i].x_outcode; 124 return 1; 125 } 126 } 127 return 0; 128 } 129 130 /* 131 * Block until input is available. 132 */ 133 static int 134 lcdkp_poll(struct lcdkp_chip *sc) 135 { 136 if (!(sc->sc_flags & LCDKP_HAS_BUF)) { 137 u_int8_t b; 138 while(lcdkp_scan(sc, &b) == 0) { 139 int err = ltsleep((void*)sc, PRIBIO | PCATCH, "kppoll", 140 HD_POLL_RATE, lcdkp_lockaddr(sc)); 141 if (err != EWOULDBLOCK) { 142 if (lcdkp_scan(sc, &b) != 0) 143 break; 144 return EINTR; 145 } 146 } 147 sc->sc_buf = b; 148 sc->sc_flags |= LCDKP_HAS_BUF; 149 } 150 return 0; 151 } 152