1 /* $NetBSD: pcf8584.c,v 1.9 2010/04/16 18:58:39 dyoung Exp $ */ 2 /* $OpenBSD: pcf8584.c,v 1.9 2007/10/20 18:46:21 kettenis Exp $ */ 3 4 /* 5 * Copyright (c) 2006 David Gwynne <dlg@openbsd.org> 6 * 7 * Permission to use, copy, modify, and distribute this software for any 8 * purpose with or without fee is hereby granted, provided that the above 9 * copyright notice and this permission notice appear in all copies. 10 * 11 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 12 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 13 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 14 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 15 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 16 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 17 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 18 */ 19 20 #include <sys/param.h> 21 #include <sys/systm.h> 22 #include <sys/device.h> 23 #include <sys/malloc.h> 24 #include <sys/kernel.h> 25 #include <sys/rwlock.h> 26 #include <sys/proc.h> 27 #include <sys/bus.h> 28 29 #include <dev/i2c/i2cvar.h> 30 31 #include <dev/ic/pcf8584var.h> 32 33 #define PCF_S0 0x00 34 #define PCF_S1 0x01 35 #define PCF_S2 0x02 36 #define PCF_S3 0x03 37 38 #define PCF_CTRL_ACK (1<<0) 39 #define PCF_CTRL_STO (1<<1) 40 #define PCF_CTRL_STA (1<<2) 41 #define PCF_CTRL_ENI (1<<3) 42 #define PCF_CTRL_ES2 (1<<4) 43 #define PCF_CTRL_ES1 (1<<5) 44 #define PCF_CTRL_ESO (1<<6) 45 #define PCF_CTRL_PIN (1<<7) 46 47 #define PCF_CTRL_START (PCF_CTRL_PIN | PCF_CTRL_ESO | \ 48 PCF_CTRL_STA | PCF_CTRL_ACK) 49 #define PCF_CTRL_STOP (PCF_CTRL_PIN | PCF_CTRL_ESO | \ 50 PCF_CTRL_STO | PCF_CTRL_ACK) 51 #define PCF_CTRL_REPSTART (PCF_CTRL_ESO | PCF_CTRL_STA | PCF_CTRL_ACK) 52 #define PCF_CTRL_IDLE (PCF_CTRL_PIN | PCF_CTRL_ESO | PCF_CTRL_ACK) 53 54 #define PCF_STAT_nBB (1<<0) 55 #define PCF_STAT_LAB (1<<1) 56 #define PCF_STAT_AAS (1<<2) 57 #define PCF_STAT_AD0 (1<<3) 58 #define PCF_STAT_LRB (1<<3) 59 #define PCF_STAT_BER (1<<4) 60 #define PCF_STAT_STS (1<<5) 61 #define PCF_STAT_PIN (1<<7) 62 63 void pcfiic_init(struct pcfiic_softc *); 64 int pcfiic_i2c_acquire_bus(void *, int); 65 void pcfiic_i2c_release_bus(void *, int); 66 int pcfiic_i2c_exec(void *, i2c_op_t, i2c_addr_t, const void *, 67 size_t, void *, size_t, int); 68 69 int pcfiic_xmit(struct pcfiic_softc *, u_int8_t, const u_int8_t *, 70 size_t); 71 int pcfiic_recv(struct pcfiic_softc *, u_int8_t, u_int8_t *, 72 size_t); 73 74 u_int8_t pcfiic_read(struct pcfiic_softc *, bus_size_t); 75 void pcfiic_write(struct pcfiic_softc *, bus_size_t, u_int8_t); 76 void pcfiic_choose_bus(struct pcfiic_softc *, u_int8_t); 77 int pcfiic_wait_nBB(struct pcfiic_softc *); 78 int pcfiic_wait_pin(struct pcfiic_softc *, volatile u_int8_t *); 79 80 void 81 pcfiic_init(struct pcfiic_softc *sc) 82 { 83 /* init S1 */ 84 pcfiic_write(sc, PCF_S1, PCF_CTRL_PIN); 85 /* own address */ 86 pcfiic_write(sc, PCF_S0, sc->sc_addr); 87 88 /* select clock reg */ 89 pcfiic_write(sc, PCF_S1, PCF_CTRL_PIN|PCF_CTRL_ES1); 90 pcfiic_write(sc, PCF_S0, sc->sc_clock); 91 92 pcfiic_write(sc, PCF_S1, PCF_CTRL_IDLE); 93 94 delay(200000); /* Multi-Master mode, wait for longest i2c message */ 95 } 96 97 void 98 pcfiic_attach(struct pcfiic_softc *sc, i2c_addr_t addr, u_int8_t clock, 99 int swapregs) 100 { 101 struct i2cbus_attach_args iba; 102 103 if (swapregs) { 104 sc->sc_regmap[PCF_S1] = PCF_S0; 105 sc->sc_regmap[PCF_S0] = PCF_S1; 106 } else { 107 sc->sc_regmap[PCF_S0] = PCF_S0; 108 sc->sc_regmap[PCF_S1] = PCF_S1; 109 } 110 sc->sc_clock = clock; 111 sc->sc_addr = addr; 112 113 pcfiic_init(sc); 114 115 printf("\n"); 116 117 if (sc->sc_master) 118 pcfiic_choose_bus(sc, 0); 119 120 rw_init(&sc->sc_lock); 121 sc->sc_i2c.ic_cookie = sc; 122 sc->sc_i2c.ic_acquire_bus = pcfiic_i2c_acquire_bus; 123 sc->sc_i2c.ic_release_bus = pcfiic_i2c_release_bus; 124 sc->sc_i2c.ic_exec = pcfiic_i2c_exec; 125 126 bzero(&iba, sizeof(iba)); 127 iba.iba_tag = &sc->sc_i2c; 128 config_found(sc->sc_dev, &iba, iicbus_print); 129 } 130 131 int 132 pcfiic_intr(void *arg) 133 { 134 return (0); 135 } 136 137 int 138 pcfiic_i2c_acquire_bus(void *arg, int flags) 139 { 140 struct pcfiic_softc *sc = arg; 141 142 if (cold || sc->sc_poll || (flags & I2C_F_POLL)) 143 return (0); 144 145 rw_enter(&sc->sc_lock, RW_WRITER); 146 return 0; 147 } 148 149 void 150 pcfiic_i2c_release_bus(void *arg, int flags) 151 { 152 struct pcfiic_softc *sc = arg; 153 154 if (cold || sc->sc_poll || (flags & I2C_F_POLL)) 155 return; 156 157 rw_exit(&sc->sc_lock); 158 } 159 160 int 161 pcfiic_i2c_exec(void *arg, i2c_op_t op, i2c_addr_t addr, 162 const void *cmdbuf, size_t cmdlen, void *buf, size_t len, int flags) 163 { 164 struct pcfiic_softc *sc = arg; 165 int ret = 0; 166 167 #if 0 168 printf("%s: exec op: %d addr: 0x%x cmdlen: %d len: %d flags 0x%x\n", 169 device_xname(sc->sc_dev), op, addr, (int)cmdlen, (int)len, flags); 170 #endif 171 172 if (cold || sc->sc_poll) 173 flags |= I2C_F_POLL; 174 175 if (sc->sc_master) 176 pcfiic_choose_bus(sc, addr >> 7); 177 178 if (cmdlen > 0) 179 if (pcfiic_xmit(sc, addr & 0x7f, cmdbuf, cmdlen) != 0) 180 return (1); 181 182 if (len > 0) { 183 if (I2C_OP_WRITE_P(op)) 184 ret = pcfiic_xmit(sc, addr & 0x7f, buf, len); 185 else 186 ret = pcfiic_recv(sc, addr & 0x7f, buf, len); 187 } 188 return (ret); 189 } 190 191 int 192 pcfiic_xmit(struct pcfiic_softc *sc, u_int8_t addr, const u_int8_t *buf, 193 size_t len) 194 { 195 int i, err = 0; 196 volatile u_int8_t r; 197 198 if (pcfiic_wait_nBB(sc) != 0) 199 return (1); 200 201 pcfiic_write(sc, PCF_S0, addr << 1); 202 pcfiic_write(sc, PCF_S1, PCF_CTRL_START); 203 204 for (i = 0; i <= len; i++) { 205 if (pcfiic_wait_pin(sc, &r) != 0) { 206 pcfiic_write(sc, PCF_S1, PCF_CTRL_STOP); 207 return (1); 208 } 209 210 if (r & PCF_STAT_LRB) { 211 err = 1; 212 break; 213 } 214 215 if (i < len) 216 pcfiic_write(sc, PCF_S0, buf[i]); 217 } 218 pcfiic_write(sc, PCF_S1, PCF_CTRL_STOP); 219 return (err); 220 } 221 222 int 223 pcfiic_recv(struct pcfiic_softc *sc, u_int8_t addr, u_int8_t *buf, size_t len) 224 { 225 int i = 0, err = 0; 226 volatile u_int8_t r; 227 228 if (pcfiic_wait_nBB(sc) != 0) 229 return (1); 230 231 pcfiic_write(sc, PCF_S0, (addr << 1) | 0x01); 232 pcfiic_write(sc, PCF_S1, PCF_CTRL_START); 233 234 for (i = 0; i <= len; i++) { 235 if (pcfiic_wait_pin(sc, &r) != 0) { 236 pcfiic_write(sc, PCF_S1, PCF_CTRL_STOP); 237 return (1); 238 } 239 240 if ((i != len) && (r & PCF_STAT_LRB)) { 241 pcfiic_write(sc, PCF_S1, PCF_CTRL_STOP); 242 return (1); 243 } 244 245 if (i == len - 1) { 246 pcfiic_write(sc, PCF_S1, PCF_CTRL_ESO); 247 } else if (i == len) { 248 pcfiic_write(sc, PCF_S1, PCF_CTRL_STOP); 249 } 250 251 r = pcfiic_read(sc, PCF_S0); 252 if (i > 0) 253 buf[i - 1] = r; 254 } 255 return (err); 256 } 257 258 u_int8_t 259 pcfiic_read(struct pcfiic_softc *sc, bus_size_t r) 260 { 261 bus_space_barrier(sc->sc_iot, sc->sc_ioh, sc->sc_regmap[r], 1, 262 BUS_SPACE_BARRIER_READ); 263 return (bus_space_read_1(sc->sc_iot, sc->sc_ioh, sc->sc_regmap[r])); 264 } 265 266 void 267 pcfiic_write(struct pcfiic_softc *sc, bus_size_t r, u_int8_t v) 268 { 269 volatile uint8_t junk; 270 bus_space_write_1(sc->sc_iot, sc->sc_ioh, sc->sc_regmap[r], v); 271 junk = bus_space_read_1(sc->sc_iot, sc->sc_ioh, PCF_S1); 272 } 273 274 void 275 pcfiic_choose_bus(struct pcfiic_softc *sc, u_int8_t bus) 276 { 277 bus_space_write_1(sc->sc_iot, sc->sc_ioh2, 0, bus); 278 bus_space_barrier(sc->sc_iot, sc->sc_ioh2, 0, 1, 279 BUS_SPACE_BARRIER_WRITE); 280 } 281 282 int 283 pcfiic_wait_nBB(struct pcfiic_softc *sc) 284 { 285 int i; 286 287 for (i = 0; i < 1000; i++) { 288 if (pcfiic_read(sc, PCF_S1) & PCF_STAT_nBB) 289 return (0); 290 delay(1000); 291 } 292 return (1); 293 } 294 295 int 296 pcfiic_wait_pin(struct pcfiic_softc *sc, volatile u_int8_t *r) 297 { 298 int i; 299 300 for (i = 0; i < 1000; i++) { 301 *r = pcfiic_read(sc, PCF_S1); 302 if ((*r & PCF_STAT_PIN) == 0) 303 return (0); 304 delay(1000); 305 } 306 return (1); 307 } 308