1 /* $NetBSD: lcdkp_subr.c,v 1.7 2011/05/14 02:58:27 rmind 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 1.7 2011/05/14 02:58:27 rmind 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 62 sc->sc_flags = 0x0; 63 mutex_init(&sc->sc_lock, MUTEX_DEFAULT, IPL_NONE); 64 } 65 66 /* 67 * Scan whether input is pending, don't block if not. 68 */ 69 int 70 lcdkp_scankey(struct lcdkp_chip *sc) 71 { 72 int ret; 73 74 if ((sc->sc_knum == 0) || (sc->sc_kpad == NULL)) 75 return 0; 76 77 mutex_enter(&sc->sc_lock); 78 if (!(sc->sc_flags & LCDKP_HAS_BUF)) { 79 u_int8_t b; 80 if (lcdkp_scan(sc, &b) != 0) { 81 sc->sc_buf = b; 82 sc->sc_flags |= LCDKP_HAS_BUF; 83 } 84 } 85 ret = (sc->sc_flags & LCDKP_HAS_BUF); 86 mutex_exit(&sc->sc_lock); 87 88 return ret; 89 } 90 91 /* 92 * Read new key code, block if needed. 93 */ 94 int 95 lcdkp_readkey(struct lcdkp_chip *sc, u_int8_t *result) 96 { 97 int error; 98 99 if ((sc->sc_knum == 0) || (sc->sc_kpad == NULL)) 100 return EIO; 101 102 mutex_enter(&sc->sc_lock); 103 if ( (error = lcdkp_poll(sc)) == 0) { 104 *result = sc->sc_buf; 105 sc->sc_flags &= ~LCDKP_HAS_BUF; 106 } 107 mutex_exit(&sc->sc_lock); 108 109 return 0; 110 } 111 112 /* 113 * Scan the keypad and translate the input. 114 */ 115 static u_char 116 lcdkp_scan(struct lcdkp_chip *sc, u_int8_t *b) 117 { 118 u_int8_t i; 119 u_int8_t c; 120 121 c = lcdkp_dr_read(sc); 122 for (i = 0; i < sc->sc_knum; i++) { 123 if (sc->sc_kpad[i].x_keycode == c) { 124 *b = sc->sc_kpad[i].x_outcode; 125 return 1; 126 } 127 } 128 return 0; 129 } 130 131 /* 132 * Block until input is available. 133 */ 134 static int 135 lcdkp_poll(struct lcdkp_chip *sc) 136 { 137 int error; 138 uint8_t b; 139 140 KASSERT(mutex_owned(&sc->sc_lock)); 141 142 if (sc->sc_flags & LCDKP_HAS_BUF) { 143 return 0; 144 } 145 while (lcdkp_scan(sc, &b) == 0) { 146 error = mtsleep((void*)sc, PRIBIO | PCATCH, "kppoll", 147 HD_POLL_RATE, &sc->sc_lock); 148 if (error != EWOULDBLOCK) { 149 if (lcdkp_scan(sc, &b) != 0) 150 break; 151 return EINTR; 152 } 153 } 154 sc->sc_buf = b; 155 sc->sc_flags |= LCDKP_HAS_BUF; 156 return 0; 157 } 158