1/* $NetBSD: rtciic.c,v 1.5 2021/08/07 16:19:00 thorpej Exp $ */ 2/* 3 * Copyright (c) 2011 KIYOHARA Takashi 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 17 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 18 * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, 19 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 20 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 21 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 23 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN 24 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 25 * POSSIBILITY OF SUCH DAMAGE. 26 * 27 */ 28#include <sys/cdefs.h> 29__KERNEL_RCSID(0, "$NetBSD: rtciic.c,v 1.5 2021/08/07 16:19:00 thorpej Exp $"); 30 31#include <sys/param.h> 32#include <sys/bus.h> 33#include <sys/device.h> 34#include <sys/errno.h> 35 36#include <machine/autoconf.h> 37 38#include <dev/i2c/i2cvar.h> 39#include <dev/i2c/i2c_bitbang.h> 40 41#include "locators.h" 42 43#ifdef RTCIIC_DEBUG 44#define DPRINTF(x) printf x 45#else 46#define DPRINTF(x) 47#endif 48 49#define RTCIIC_SDAR (1 << 3) /* received serial data */ 50#define RTCIIC_SDAW (1 << 2) /* sended serial data */ 51#define RTCIIC_SCL (1 << 1) /* serial clock */ 52#define RTCIIC_RW (1 << 0) /* data direction (0:write, 1:read) */ 53 54/* This device is Big Endian */ 55#define RTCIIC_READ(sc) \ 56 bswap16(bus_space_read_2((sc)->sc_iot, (sc)->sc_ioh, 0)) 57#define RTCIIC_WRITE(sc, val) \ 58 bus_space_write_2((sc)->sc_iot, (sc)->sc_ioh, 0, bswap16(val)) 59 60struct rtciic_softc { 61 device_t sc_dev; 62 63 bus_space_tag_t sc_iot; 64 bus_space_handle_t sc_ioh; 65 66 struct i2c_controller sc_i2c; 67 struct i2c_bitbang_ops sc_bops; 68 69 int sc_rw; 70}; 71 72static int rtciic_match(device_t, cfdata_t , void *); 73static void rtciic_attach(device_t, device_t, void *); 74 75static int rtciic_send_start(void *, int); 76static int rtciic_send_stop(void *, int); 77static int rtciic_initiate_xfer(void *, i2c_addr_t, int); 78static int rtciic_read_byte(void *, uint8_t *, int); 79static int rtciic_write_byte(void *, uint8_t, int); 80 81static void rtciic_set_dir(void *, uint32_t); 82static void rtciic_set_bits(void *, uint32_t); 83static uint32_t rtciic_read_bits(void *); 84 85CFATTACH_DECL_NEW(rtciic, sizeof(struct rtciic_softc), 86 rtciic_match, rtciic_attach, NULL, NULL); 87 88static int 89rtciic_match(device_t parent, cfdata_t match, void *aux) 90{ 91 struct mainbus_attach_args *ma = aux; 92 93 if (strcmp(ma->ma_name, match->cf_name) != 0) 94 return 0; 95 96 /* Disallow wildcarded values. */ 97 if (ma->ma_addr1 == MAINBUSCF_ADDR1_DEFAULT) 98 return 0; 99 100 /* no irq */ 101 if (ma->ma_irq1 != MAINBUSCF_IRQ1_DEFAULT) 102 return 0; 103 104 return 1; 105} 106 107void 108rtciic_attach(device_t parent, device_t self, void *aux) 109{ 110 struct rtciic_softc *sc = device_private(self); 111 struct mainbus_attach_args *ma = aux; 112 struct i2cbus_attach_args iba; 113 114 sc->sc_dev = self; 115 116 aprint_normal("\n"); 117 aprint_naive("\n"); 118 119 /* Map I/O space(16bit). */ 120 sc->sc_iot = 0; 121 if (bus_space_map(sc->sc_iot, ma->ma_addr1, 2, 0, &sc->sc_ioh)) { 122 aprint_error_dev(self, "can't map registers\n"); 123 return; 124 } 125 sc->sc_rw = RTCIIC_READ(sc) & RTCIIC_RW; 126 127 /* register with iic */ 128 iic_tag_init(&sc->sc_i2c); 129 sc->sc_i2c.ic_cookie = sc; 130 sc->sc_i2c.ic_send_start = rtciic_send_start; 131 sc->sc_i2c.ic_send_stop = rtciic_send_stop; 132 sc->sc_i2c.ic_initiate_xfer = rtciic_initiate_xfer; 133 sc->sc_i2c.ic_read_byte = rtciic_read_byte; 134 sc->sc_i2c.ic_write_byte = rtciic_write_byte; 135 136 sc->sc_bops.ibo_set_dir = rtciic_set_dir; 137 sc->sc_bops.ibo_set_bits = rtciic_set_bits; 138 sc->sc_bops.ibo_read_bits = rtciic_read_bits; 139 sc->sc_bops.ibo_bits[I2C_BIT_SDA] = RTCIIC_SDAW; 140 sc->sc_bops.ibo_bits[I2C_BIT_SCL] = RTCIIC_SCL; 141 sc->sc_bops.ibo_bits[I2C_BIT_OUTPUT] = 0; 142 sc->sc_bops.ibo_bits[I2C_BIT_INPUT] = RTCIIC_RW; 143 144 memset(&iba, 0, sizeof(iba)); 145 iba.iba_tag = &sc->sc_i2c; 146 config_found(sc->sc_dev, &iba, iicbus_print, CFARGS_NONE); 147} 148 149static int 150rtciic_send_start(void *arg, int flags) 151{ 152 struct rtciic_softc *sc = arg; 153 154 return i2c_bitbang_send_start(sc, flags, &sc->sc_bops); 155} 156 157static int 158rtciic_send_stop(void *arg, int flags) 159{ 160 struct rtciic_softc *sc = arg; 161 162 return i2c_bitbang_send_stop(sc, flags, &sc->sc_bops); 163} 164 165static int 166rtciic_initiate_xfer(void *arg, i2c_addr_t addr, int flags) 167{ 168 struct rtciic_softc *sc = arg; 169 170 return i2c_bitbang_initiate_xfer(sc, addr, flags, &sc->sc_bops); 171} 172 173static int 174rtciic_read_byte(void *arg, uint8_t *vp, int flags) 175{ 176 struct rtciic_softc *sc = arg; 177 178 return i2c_bitbang_read_byte(sc, vp, flags, &sc->sc_bops); 179} 180 181static int 182rtciic_write_byte(void *arg, uint8_t v, int flags) 183{ 184 struct rtciic_softc *sc = arg; 185 186 return i2c_bitbang_write_byte(sc, v, flags, &sc->sc_bops); 187} 188 189 190static void 191rtciic_set_dir(void *arg, uint32_t bits) 192{ 193 struct rtciic_softc *sc = arg; 194 uint16_t reg; 195 196 DPRINTF(("%s: set dir %s\n", 197 device_xname(sc->sc_dev), (bits & RTCIIC_RW) ? "READ" : "WRITE")); 198 199 if (sc->sc_rw != (bits & RTCIIC_RW)) { 200 reg = RTCIIC_READ(sc); 201 reg &= ~RTCIIC_RW; 202 reg |= bits; 203 RTCIIC_WRITE(sc, reg); 204 delay(30); 205 sc->sc_rw = bits & RTCIIC_RW; 206 } 207} 208 209static void 210rtciic_set_bits(void *arg, uint32_t bits) 211{ 212 struct rtciic_softc *sc = arg; 213 214 DPRINTF(("%s: %s\n", 215 device_xname(sc->sc_dev), 216 (bits == (RTCIIC_SDAW | RTCIIC_SCL)) ? "set SDA/SCL" : 217 ((bits == RTCIIC_SDAW) ? "set SDA" : 218 ((bits == RTCIIC_SCL) ? "set SCL" : "reset")))); 219 220 if (sc->sc_rw & RTCIIC_RW) { 221 bits &= RTCIIC_SCL; 222 bits |= RTCIIC_RW; 223 } 224 RTCIIC_WRITE(sc, bits); 225 delay(40); 226} 227 228static uint32_t 229rtciic_read_bits(void *arg) 230{ 231 struct rtciic_softc *sc = arg; 232 uint8_t rv, v; 233 234 v = RTCIIC_READ(sc); 235 rv = v & RTCIIC_SCL; 236 if (v & RTCIIC_SDAR) 237 rv |= RTCIIC_SDAW; 238 239 DPRINTF(("%s: read %s\n", 240 device_xname(sc->sc_dev), 241 (rv == (RTCIIC_SDAW | RTCIIC_SCL)) ? "SDA/SCL" : 242 ((rv == RTCIIC_SDAW) ? "SDA" : 243 ((rv == RTCIIC_SCL) ? "SCL" : "no")))); 244 245 return (uint32_t)rv; 246} 247