1 /* $NetBSD: tsciic.c,v 1.1 2014/02/21 12:23:30 jdc Exp $ */ 2 3 /* 4 * Copyright (c) 2013 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Julian Coleman. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32 #include <sys/cdefs.h> 33 34 __KERNEL_RCSID(0, "$NetBSD: tsciic.c,v 1.1 2014/02/21 12:23:30 jdc Exp $"); 35 36 #include <sys/param.h> 37 #include <sys/systm.h> 38 #include <sys/device.h> 39 40 #include <alpha/pci/tsreg.h> 41 #include <alpha/pci/tsvar.h> 42 43 #include <dev/i2c/i2cvar.h> 44 #include <dev/i2c/i2c_bitbang.h> 45 #include <dev/i2c/ddcvar.h> 46 47 /* I2C glue */ 48 static int tsciic_acquire_bus(void *, int); 49 static void tsciic_release_bus(void *, int); 50 static int tsciic_send_start(void *, int); 51 static int tsciic_send_stop(void *, int); 52 static int tsciic_initiate_xfer(void *, i2c_addr_t, int); 53 static int tsciic_read_byte(void *, uint8_t *, int); 54 static int tsciic_write_byte(void *, uint8_t, int); 55 56 /* I2C bitbang glue */ 57 static void tsciicbb_set_bits(void *, uint32_t); 58 static void tsciicbb_set_dir(void *, uint32_t); 59 static uint32_t tsciicbb_read(void *); 60 61 #define MPD_BIT_SDA 0x01 62 #define MPD_BIT_SCL 0x02 63 static const struct i2c_bitbang_ops tsciicbb_ops = { 64 tsciicbb_set_bits, 65 tsciicbb_set_dir, 66 tsciicbb_read, 67 { 68 MPD_BIT_SDA, 69 MPD_BIT_SCL, 70 0, 71 0 72 } 73 }; 74 75 void 76 tsciic_init(device_t self) { 77 struct tsciic_softc *sc = device_private(self); 78 struct i2cbus_attach_args iba; 79 80 mutex_init(&sc->sc_buslock, MUTEX_DEFAULT, IPL_NONE); 81 82 sc->sc_i2c.ic_cookie = sc; 83 sc->sc_i2c.ic_acquire_bus = tsciic_acquire_bus; 84 sc->sc_i2c.ic_release_bus = tsciic_release_bus; 85 sc->sc_i2c.ic_send_start = tsciic_send_start; 86 sc->sc_i2c.ic_send_stop = tsciic_send_stop; 87 sc->sc_i2c.ic_initiate_xfer = tsciic_initiate_xfer; 88 sc->sc_i2c.ic_read_byte = tsciic_read_byte; 89 sc->sc_i2c.ic_write_byte = tsciic_write_byte; 90 sc->sc_i2c.ic_exec = NULL; 91 92 memset(&iba, 0, sizeof(iba)); 93 iba.iba_tag = &sc->sc_i2c; 94 95 config_found_ia(self, "i2cbus", &iba, iicbus_print); 96 97 } 98 99 /* I2C bitbanging */ 100 static void 101 tsciicbb_set_bits(void *cookie, uint32_t bits) 102 { 103 uint64_t val; 104 105 val = (bits & MPD_BIT_SDA ? MPD_DS : 0) | 106 (bits & MPD_BIT_SCL ? MPD_CKS : 0); 107 alpha_mb(); 108 STQP(TS_C_MPD) = val; 109 alpha_mb(); 110 } 111 112 static void 113 tsciicbb_set_dir(void *cookie, uint32_t dir) 114 { 115 /* Nothing to do */ 116 } 117 118 static uint32_t 119 tsciicbb_read(void *cookie) 120 { 121 uint64_t val; 122 uint32_t bits; 123 124 val = LDQP(TS_C_MPD); 125 bits = (val & MPD_DR ? MPD_BIT_SDA : 0) | 126 (val & MPD_CKR ? MPD_BIT_SCL : 0); 127 return bits; 128 } 129 130 /* higher level I2C stuff */ 131 static int 132 tsciic_acquire_bus(void *cookie, int flags) 133 { 134 struct tsciic_softc *sc = cookie; 135 136 mutex_enter(&sc->sc_buslock); 137 return 0; 138 } 139 140 static void 141 tsciic_release_bus(void *cookie, int flags) 142 { 143 struct tsciic_softc *sc = cookie; 144 145 mutex_exit(&sc->sc_buslock); 146 } 147 148 static int 149 tsciic_send_start(void *cookie, int flags) 150 { 151 return (i2c_bitbang_send_start(cookie, flags, &tsciicbb_ops)); 152 } 153 154 static int 155 tsciic_send_stop(void *cookie, int flags) 156 { 157 return (i2c_bitbang_send_stop(cookie, flags, &tsciicbb_ops)); 158 } 159 160 static int 161 tsciic_initiate_xfer(void *cookie, i2c_addr_t addr, int flags) 162 { 163 return (i2c_bitbang_initiate_xfer(cookie, addr, flags, 164 &tsciicbb_ops)); 165 } 166 167 static int 168 tsciic_read_byte(void *cookie, uint8_t *valp, int flags) 169 { 170 return (i2c_bitbang_read_byte(cookie, valp, flags, &tsciicbb_ops)); 171 } 172 173 static int 174 tsciic_write_byte(void *cookie, uint8_t val, int flags) 175 { 176 return (i2c_bitbang_write_byte(cookie, val, flags, &tsciicbb_ops)); 177 } 178