1 /* $NetBSD: m41st84.c,v 1.6 2005/12/13 20:55:46 abs Exp $ */ 2 3 /* 4 * Copyright (c) 2003 Wasabi Systems, Inc. 5 * All rights reserved. 6 * 7 * Written by Steve C. Woodford and Jason R. Thorpe for Wasabi Systems, Inc. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 3. All advertising materials mentioning features or use of this software 18 * must display the following acknowledgement: 19 * This product includes software developed for the NetBSD Project by 20 * Wasabi Systems, Inc. 21 * 4. The name of Wasabi Systems, Inc. may not be used to endorse 22 * or promote products derived from this software without specific prior 23 * written permission. 24 * 25 * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND 26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 27 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 28 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL WASABI SYSTEMS, INC 29 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 30 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 31 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 32 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 33 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 34 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 35 * POSSIBILITY OF SUCH DAMAGE. 36 */ 37 38 #include <sys/param.h> 39 #include <sys/systm.h> 40 #include <sys/device.h> 41 #include <sys/kernel.h> 42 #include <sys/fcntl.h> 43 #include <sys/uio.h> 44 #include <sys/conf.h> 45 #include <sys/event.h> 46 47 #include <dev/clock_subr.h> 48 49 #include <dev/i2c/i2cvar.h> 50 #include <dev/i2c/m41st84reg.h> 51 52 struct strtc_softc { 53 struct device sc_dev; 54 i2c_tag_t sc_tag; 55 int sc_address; 56 int sc_open; 57 struct todr_chip_handle sc_todr; 58 }; 59 60 static void strtc_attach(struct device *, struct device *, void *); 61 static int strtc_match(struct device *, struct cfdata *, void *); 62 63 CFATTACH_DECL(strtc, sizeof(struct strtc_softc), 64 strtc_match, strtc_attach, NULL, NULL); 65 extern struct cfdriver strtc_cd; 66 67 dev_type_open(strtc_open); 68 dev_type_close(strtc_close); 69 dev_type_read(strtc_read); 70 dev_type_write(strtc_write); 71 72 const struct cdevsw strtc_cdevsw = { 73 strtc_open, strtc_close, strtc_read, strtc_write, noioctl, 74 nostop, notty, nopoll, nommap, nokqfilter 75 }; 76 77 static int strtc_clock_read(struct strtc_softc *, struct clock_ymdhms *); 78 static int strtc_clock_write(struct strtc_softc *, struct clock_ymdhms *); 79 static int strtc_gettime(struct todr_chip_handle *, volatile struct timeval *); 80 static int strtc_settime(struct todr_chip_handle *, volatile struct timeval *); 81 static int strtc_getcal(struct todr_chip_handle *, int *); 82 static int strtc_setcal(struct todr_chip_handle *, int); 83 84 static int 85 strtc_match(struct device *parent, struct cfdata *cf, void *arg) 86 { 87 struct i2c_attach_args *ia = arg; 88 89 if (ia->ia_addr == M41ST84_ADDR) 90 return (1); 91 92 return (0); 93 } 94 95 static void 96 strtc_attach(struct device *parent, struct device *self, void *arg) 97 { 98 struct strtc_softc *sc = (struct strtc_softc *)self; 99 struct i2c_attach_args *ia = arg; 100 101 aprint_naive(": Real-time Clock/NVRAM\n"); 102 aprint_normal(": M41ST84 Real-time Clock/NVRAM\n"); 103 104 sc->sc_tag = ia->ia_tag; 105 sc->sc_address = ia->ia_addr; 106 sc->sc_open = 0; 107 sc->sc_todr.cookie = sc; 108 sc->sc_todr.todr_gettime = strtc_gettime; 109 sc->sc_todr.todr_settime = strtc_settime; 110 sc->sc_todr.todr_getcal = strtc_getcal; 111 sc->sc_todr.todr_setcal = strtc_setcal; 112 sc->sc_todr.todr_setwen = NULL; 113 114 todr_attach(&sc->sc_todr); 115 } 116 117 /*ARGSUSED*/ 118 int 119 strtc_open(dev_t dev, int flag, int fmt, struct lwp *l) 120 { 121 struct strtc_softc *sc; 122 123 if ((sc = device_lookup(&strtc_cd, minor(dev))) == NULL) 124 return (ENXIO); 125 126 /* XXX: Locking */ 127 128 if (sc->sc_open) 129 return (EBUSY); 130 131 sc->sc_open = 1; 132 return (0); 133 } 134 135 /*ARGSUSED*/ 136 int 137 strtc_close(dev_t dev, int flag, int fmt, struct lwp *l) 138 { 139 struct strtc_softc *sc; 140 141 if ((sc = device_lookup(&strtc_cd, minor(dev))) == NULL) 142 return (ENXIO); 143 144 sc->sc_open = 0; 145 return (0); 146 } 147 148 /*ARGSUSED*/ 149 int 150 strtc_read(dev_t dev, struct uio *uio, int flags) 151 { 152 struct strtc_softc *sc; 153 u_int8_t ch, cmdbuf[1]; 154 int a, error; 155 156 if ((sc = device_lookup(&strtc_cd, minor(dev))) == NULL) 157 return (ENXIO); 158 159 if (uio->uio_offset >= M41ST84_USER_RAM_SIZE) 160 return (EINVAL); 161 162 if ((error = iic_acquire_bus(sc->sc_tag, 0)) != 0) 163 return (error); 164 165 while (uio->uio_resid && uio->uio_offset < M41ST84_USER_RAM_SIZE) { 166 a = (int)uio->uio_offset; 167 cmdbuf[0] = a + M41ST84_USER_RAM; 168 if ((error = iic_exec(sc->sc_tag, I2C_OP_READ_WITH_STOP, 169 sc->sc_address, cmdbuf, 1, 170 &ch, 1, 0)) != 0) { 171 iic_release_bus(sc->sc_tag, 0); 172 printf("%s: strtc_read: read failed at 0x%x\n", 173 sc->sc_dev.dv_xname, a); 174 return (error); 175 } 176 if ((error = uiomove(&ch, 1, uio)) != 0) { 177 iic_release_bus(sc->sc_tag, 0); 178 return (error); 179 } 180 } 181 182 iic_release_bus(sc->sc_tag, 0); 183 184 return (0); 185 } 186 187 /*ARGSUSED*/ 188 int 189 strtc_write(dev_t dev, struct uio *uio, int flags) 190 { 191 struct strtc_softc *sc; 192 u_int8_t cmdbuf[2]; 193 int a, error; 194 195 if ((sc = device_lookup(&strtc_cd, minor(dev))) == NULL) 196 return (ENXIO); 197 198 if (uio->uio_offset >= M41ST84_USER_RAM_SIZE) 199 return (EINVAL); 200 201 if ((error = iic_acquire_bus(sc->sc_tag, 0)) != 0) 202 return (error); 203 204 while (uio->uio_resid && uio->uio_offset < M41ST84_USER_RAM_SIZE) { 205 a = (int)uio->uio_offset; 206 cmdbuf[0] = a + M41ST84_USER_RAM; 207 if ((error = uiomove(&cmdbuf[1], 1, uio)) != 0) 208 break; 209 210 if ((error = iic_exec(sc->sc_tag, 211 uio->uio_resid ? I2C_OP_WRITE : I2C_OP_WRITE_WITH_STOP, 212 sc->sc_address, cmdbuf, 1, &cmdbuf[1], 1, 0)) != 0) { 213 printf("%s: strtc_write: write failed at 0x%x\n", 214 sc->sc_dev.dv_xname, a); 215 break; 216 } 217 } 218 219 iic_release_bus(sc->sc_tag, 0); 220 221 return (error); 222 } 223 224 static int 225 strtc_gettime(struct todr_chip_handle *ch, volatile struct timeval *tv) 226 { 227 struct strtc_softc *sc = ch->cookie; 228 struct clock_ymdhms dt, check; 229 int retries; 230 231 memset(&dt, 0, sizeof(dt)); 232 memset(&check, 0, sizeof(check)); 233 234 /* 235 * Since we don't support Burst Read, we have to read the clock twice 236 * until we get two consecutive identical results. 237 */ 238 retries = 5; 239 do { 240 strtc_clock_read(sc, &dt); 241 strtc_clock_read(sc, &check); 242 } while (memcmp(&dt, &check, sizeof(check)) != 0 && --retries); 243 244 tv->tv_sec = clock_ymdhms_to_secs(&dt); 245 tv->tv_usec = 0; 246 247 return (0); 248 } 249 250 static int 251 strtc_settime(struct todr_chip_handle *ch, volatile struct timeval *tv) 252 { 253 struct strtc_softc *sc = ch->cookie; 254 struct clock_ymdhms dt; 255 256 clock_secs_to_ymdhms(tv->tv_sec, &dt); 257 258 if (strtc_clock_write(sc, &dt) == 0) 259 return (-1); 260 261 return (0); 262 } 263 264 static int 265 strtc_setcal(struct todr_chip_handle *ch, int cal) 266 { 267 268 return (EOPNOTSUPP); 269 } 270 271 static int 272 strtc_getcal(struct todr_chip_handle *ch, int *cal) 273 { 274 275 return (EOPNOTSUPP); 276 } 277 278 static int 279 strtc_clock_read(struct strtc_softc *sc, struct clock_ymdhms *dt) 280 { 281 u_int8_t bcd[M41ST84_REG_DATE_BYTES], cmdbuf[1]; 282 int i; 283 284 if (iic_acquire_bus(sc->sc_tag, I2C_F_POLL)) { 285 printf("%s: strtc_clock_read: failed to acquire I2C bus\n", 286 sc->sc_dev.dv_xname); 287 return (0); 288 } 289 290 /* 291 * Check for the HT bit -- if set, then clock lost power & stopped 292 * If that happened, then clear the bit so that the clock will have 293 * a chance to run again. 294 */ 295 cmdbuf[0] = M41ST84_REG_AL_HOUR; 296 if (iic_exec(sc->sc_tag, I2C_OP_READ, sc->sc_address, 297 cmdbuf, 1, &cmdbuf[1], 1, I2C_F_POLL)) { 298 iic_release_bus(sc->sc_tag, I2C_F_POLL); 299 printf("%s: strtc_clock_read: failed to read HT\n", 300 sc->sc_dev.dv_xname); 301 return (0); 302 } 303 if (cmdbuf[1] & M41ST84_AL_HOUR_HT) { 304 cmdbuf[1] &= ~M41ST84_AL_HOUR_HT; 305 if (iic_exec(sc->sc_tag, I2C_OP_WRITE, sc->sc_address, 306 cmdbuf, 1, &cmdbuf[1], 1, I2C_F_POLL)) { 307 iic_release_bus(sc->sc_tag, I2C_F_POLL); 308 printf("%s: strtc_clock_read: failed to reset HT\n", 309 sc->sc_dev.dv_xname); 310 return (0); 311 } 312 } 313 314 /* Read each RTC register in order. */ 315 for (i = M41ST84_REG_CSEC; i < M41ST84_REG_DATE_BYTES; i++) { 316 cmdbuf[0] = i; 317 318 if (iic_exec(sc->sc_tag, I2C_OP_READ_WITH_STOP, 319 sc->sc_address, cmdbuf, 1, 320 &bcd[i], 1, I2C_F_POLL)) { 321 iic_release_bus(sc->sc_tag, I2C_F_POLL); 322 printf("%s: strtc_clock_read: failed to read rtc " 323 "at 0x%x\n", sc->sc_dev.dv_xname, i); 324 return (0); 325 } 326 } 327 328 /* Done with I2C */ 329 iic_release_bus(sc->sc_tag, I2C_F_POLL); 330 331 /* 332 * Convert the M41ST84's register values into something useable 333 */ 334 dt->dt_sec = FROMBCD(bcd[M41ST84_REG_SEC] & M41ST84_SEC_MASK); 335 dt->dt_min = FROMBCD(bcd[M41ST84_REG_MIN] & M41ST84_MIN_MASK); 336 dt->dt_hour = FROMBCD(bcd[M41ST84_REG_CENHR] & M41ST84_HOUR_MASK); 337 dt->dt_day = FROMBCD(bcd[M41ST84_REG_DATE] & M41ST84_DATE_MASK); 338 dt->dt_mon = FROMBCD(bcd[M41ST84_REG_MONTH] & M41ST84_MONTH_MASK); 339 340 /* XXX: Should be an MD way to specify EPOCH used by BIOS/Firmware */ 341 dt->dt_year = FROMBCD(bcd[M41ST84_REG_YEAR]) + POSIX_BASE_YEAR; 342 343 return (1); 344 } 345 346 static int 347 strtc_clock_write(struct strtc_softc *sc, struct clock_ymdhms *dt) 348 { 349 uint8_t bcd[M41ST84_REG_DATE_BYTES], cmdbuf[2]; 350 int i; 351 352 /* 353 * Convert our time representation into something the M41ST84 354 * can understand. 355 */ 356 bcd[M41ST84_REG_CSEC] = TOBCD(0); /* must always write as 0 */ 357 bcd[M41ST84_REG_SEC] = TOBCD(dt->dt_sec); 358 bcd[M41ST84_REG_MIN] = TOBCD(dt->dt_min); 359 bcd[M41ST84_REG_CENHR] = TOBCD(dt->dt_hour); 360 bcd[M41ST84_REG_DATE] = TOBCD(dt->dt_day); 361 bcd[M41ST84_REG_DAY] = TOBCD(dt->dt_wday); 362 bcd[M41ST84_REG_MONTH] = TOBCD(dt->dt_mon); 363 bcd[M41ST84_REG_YEAR] = TOBCD((dt->dt_year - POSIX_BASE_YEAR) % 100); 364 365 if (iic_acquire_bus(sc->sc_tag, I2C_F_POLL)) { 366 printf("%s: strtc_clock_write: failed to acquire I2C bus\n", 367 sc->sc_dev.dv_xname); 368 return (0); 369 } 370 371 /* Stop the clock */ 372 cmdbuf[0] = M41ST84_REG_SEC; 373 cmdbuf[1] = M41ST84_SEC_ST; 374 375 if (iic_exec(sc->sc_tag, I2C_OP_WRITE, sc->sc_address, 376 cmdbuf, 1, &cmdbuf[1], 1, I2C_F_POLL)) { 377 iic_release_bus(sc->sc_tag, I2C_F_POLL); 378 printf("%s: strtc_clock_write: failed to Hold Clock\n", 379 sc->sc_dev.dv_xname); 380 return (0); 381 } 382 383 /* 384 * Check for the HT bit -- if set, then clock lost power & stopped 385 * If that happened, then clear the bit so that the clock will have 386 * a chance to run again. 387 */ 388 cmdbuf[0] = M41ST84_REG_AL_HOUR; 389 if (iic_exec(sc->sc_tag, I2C_OP_READ, sc->sc_address, 390 cmdbuf, 1, &cmdbuf[1], 1, I2C_F_POLL)) { 391 iic_release_bus(sc->sc_tag, I2C_F_POLL); 392 printf("%s: strtc_clock_write: failed to read HT\n", 393 sc->sc_dev.dv_xname); 394 return (0); 395 } 396 if (cmdbuf[1] & M41ST84_AL_HOUR_HT) { 397 cmdbuf[1] &= ~M41ST84_AL_HOUR_HT; 398 if (iic_exec(sc->sc_tag, I2C_OP_WRITE, sc->sc_address, 399 cmdbuf, 1, &cmdbuf[1], 1, I2C_F_POLL)) { 400 iic_release_bus(sc->sc_tag, I2C_F_POLL); 401 printf("%s: strtc_clock_write: failed to reset HT\n", 402 sc->sc_dev.dv_xname); 403 return (0); 404 } 405 } 406 407 /* 408 * Write registers in reverse order. The last write (to the Seconds 409 * register) will undo the Clock Hold, above. 410 */ 411 for (i = M41ST84_REG_DATE_BYTES - 1; i >= 0; i--) { 412 cmdbuf[0] = i; 413 if (iic_exec(sc->sc_tag, 414 i ? I2C_OP_WRITE : I2C_OP_WRITE_WITH_STOP, 415 sc->sc_address, cmdbuf, 1, &bcd[i], 1, 416 I2C_F_POLL)) { 417 iic_release_bus(sc->sc_tag, I2C_F_POLL); 418 printf("%s: strtc_clock_write: failed to write rtc " 419 " at 0x%x\n", sc->sc_dev.dv_xname, i); 420 /* XXX: Clock Hold is likely still asserted! */ 421 return (0); 422 } 423 } 424 425 iic_release_bus(sc->sc_tag, I2C_F_POLL); 426 427 return (1); 428 } 429