pxa2x0_i2c.c revision 1.3.34.1
1 /* $NetBSD: pxa2x0_i2c.c,v 1.3.34.1 2009/05/13 17:16:18 jym Exp $ */ 2 /* $OpenBSD: pxa2x0_i2c.c,v 1.2 2005/05/26 03:52:07 pascoe Exp $ */ 3 4 /* 5 * Copyright (c) 2005 Christopher Pascoe <pascoe (at) 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/cdefs.h> 21 __KERNEL_RCSID(0, "$NetBSD: pxa2x0_i2c.c,v 1.3.34.1 2009/05/13 17:16:18 jym Exp $"); 22 23 #include <sys/param.h> 24 #include <sys/systm.h> 25 #include <sys/device.h> 26 27 #include <machine/bus.h> 28 29 #include <arm/xscale/pxa2x0reg.h> 30 #include <arm/xscale/pxa2x0var.h> 31 #include <arm/xscale/pxa2x0_i2c.h> 32 #include <arm/xscale/pxa2x0_gpio.h> 33 34 #define I2C_RETRY_COUNT 10 35 36 int 37 pxa2x0_i2c_attach_sub(struct pxa2x0_i2c_softc *sc) 38 { 39 40 if (bus_space_map(sc->sc_iot, PXA2X0_I2C_BASE, 41 PXA2X0_I2C_SIZE, 0, &sc->sc_ioh)) { 42 sc->sc_size = 0; 43 return EIO; 44 } 45 bus_space_barrier(sc->sc_iot, sc->sc_ioh, 0, sc->sc_size, 46 BUS_SPACE_BARRIER_READ|BUS_SPACE_BARRIER_WRITE); 47 48 pxa2x0_i2c_init(sc); 49 50 return 0; 51 } 52 53 int 54 pxa2x0_i2c_detach_sub(struct pxa2x0_i2c_softc *sc) 55 { 56 57 if (sc->sc_size) { 58 bus_space_unmap(sc->sc_iot, sc->sc_ioh, sc->sc_size); 59 sc->sc_size = 0; 60 } 61 pxa2x0_clkman_config(CKEN_I2C, 0); 62 63 return 0; 64 } 65 66 void 67 pxa2x0_i2c_init(struct pxa2x0_i2c_softc *sc) 68 { 69 70 pxa2x0_i2c_open(sc); 71 pxa2x0_i2c_close(sc); 72 } 73 74 void 75 pxa2x0_i2c_open(struct pxa2x0_i2c_softc *sc) 76 { 77 78 /* Enable the clock to the standard I2C unit. */ 79 pxa2x0_clkman_config(CKEN_I2C, 1); 80 } 81 82 void 83 pxa2x0_i2c_close(struct pxa2x0_i2c_softc *sc) 84 { 85 86 /* Reset and disable the standard I2C unit. */ 87 bus_space_write_4(sc->sc_iot, sc->sc_ioh, I2C_ICR, ICR_UR); 88 bus_space_write_4(sc->sc_iot, sc->sc_ioh, I2C_ISAR, 0); 89 delay(1); 90 pxa2x0_clkman_config(CKEN_I2C, 0); 91 } 92 93 int 94 pxa2x0_i2c_read(struct pxa2x0_i2c_softc *sc, u_char slave, u_char *valuep) 95 { 96 bus_space_tag_t iot = sc->sc_iot; 97 bus_space_handle_t ioh = sc->sc_ioh; 98 int timeout; 99 int tries = I2C_RETRY_COUNT; 100 uint32_t rv; 101 102 retry: 103 bus_space_write_4(iot, ioh, I2C_ICR, ICR_UR); 104 bus_space_write_4(iot, ioh, I2C_ISAR, 0x00); 105 bus_space_write_4(iot, ioh, I2C_ISR, ISR_ITE | ISR_IRF); 106 delay(1); 107 bus_space_write_4(iot, ioh, I2C_ICR, ICR_IUE | ICR_SCLE); 108 109 /* Write slave device address. */ 110 bus_space_write_4(iot, ioh, I2C_IDBR, (slave<<1) | 0x1); 111 rv = bus_space_read_4(iot, ioh, I2C_ICR); 112 bus_space_write_4(iot, ioh, I2C_ICR, rv | ICR_START); 113 rv = bus_space_read_4(iot, ioh, I2C_ICR); 114 bus_space_write_4(iot, ioh, I2C_ICR, rv & ~ICR_STOP); 115 rv = bus_space_read_4(iot, ioh, I2C_ICR); 116 bus_space_write_4(iot, ioh, I2C_ICR, rv | ICR_TB); 117 118 timeout = 10000; 119 while ((bus_space_read_4(iot, ioh, I2C_ISR) & ISR_ITE) == 0) { 120 if (timeout-- == 0) 121 goto err; 122 delay(1); 123 } 124 125 bus_space_write_4(iot, ioh, I2C_ISR, ISR_ITE); 126 127 rv = bus_space_read_4(iot, ioh, I2C_ICR); 128 bus_space_write_4(iot, ioh, I2C_ICR, rv & ~ICR_START); 129 130 /* Read data value. */ 131 rv = bus_space_read_4(iot, ioh, I2C_ICR); 132 bus_space_write_4(iot, ioh, I2C_ICR, rv | 133 (ICR_STOP | ICR_ACKNAK)); 134 rv = bus_space_read_4(iot, ioh, I2C_ICR); 135 bus_space_write_4(iot, ioh, I2C_ICR, rv | ICR_TB); 136 137 timeout = 10000; 138 while ((bus_space_read_4(iot, ioh, I2C_ISR) & ISR_IRF) == 0) { 139 if (timeout-- == 0) 140 goto err; 141 delay(1); 142 } 143 144 bus_space_write_4(iot, ioh, I2C_ISR, ISR_IRF); 145 146 rv = bus_space_read_4(iot, ioh, I2C_IDBR); 147 *valuep = (u_char)rv; 148 rv = bus_space_read_4(iot, ioh, I2C_ICR); 149 bus_space_write_4(iot, ioh, I2C_ICR, rv & ~(ICR_STOP | ICR_ACKNAK)); 150 151 return 0; 152 153 err: 154 if (tries-- >= 0) 155 goto retry; 156 157 bus_space_write_4(iot, ioh, I2C_ICR, ICR_UR); 158 bus_space_write_4(iot, ioh, I2C_ISAR, 0x00); 159 bus_space_write_4(iot, ioh, I2C_ISR, ISR_ITE | ISR_IRF); 160 bus_space_write_4(iot, ioh, I2C_ICR, ICR_IUE | ICR_SCLE); 161 162 return EIO; 163 } 164 165 int 166 pxa2x0_i2c_write(struct pxa2x0_i2c_softc *sc, u_char slave, u_char value) 167 { 168 bus_space_tag_t iot = sc->sc_iot; 169 bus_space_handle_t ioh = sc->sc_ioh; 170 int timeout; 171 int tries = I2C_RETRY_COUNT; 172 uint32_t rv; 173 174 retry: 175 bus_space_write_4(iot, ioh, I2C_ICR, ICR_UR); 176 bus_space_write_4(iot, ioh, I2C_ISAR, 0x00); 177 bus_space_write_4(iot, ioh, I2C_ISR, ISR_ITE); 178 delay(1); 179 bus_space_write_4(iot, ioh, I2C_ICR, ICR_IUE | ICR_SCLE); 180 181 /* Write slave device address. */ 182 bus_space_write_4(iot, ioh, I2C_IDBR, (slave<<1)); 183 rv = bus_space_read_4(iot, ioh, I2C_ICR); 184 bus_space_write_4(iot, ioh, I2C_ICR, rv | ICR_START); 185 rv = bus_space_read_4(iot, ioh, I2C_ICR); 186 bus_space_write_4(iot, ioh, I2C_ICR, rv & ~ICR_STOP); 187 rv = bus_space_read_4(iot, ioh, I2C_ICR); 188 bus_space_write_4(iot, ioh, I2C_ICR, rv | ICR_TB); 189 190 timeout = 10000; 191 while ((bus_space_read_4(iot, ioh, I2C_ISR) & ISR_ITE) == 0) { 192 if (timeout-- == 0) 193 goto err; 194 delay(1); 195 } 196 if ((bus_space_read_4(iot, ioh, I2C_ISR) & ISR_ACKNAK) != 0) 197 goto err; 198 199 bus_space_write_4(iot, ioh, I2C_ISR, ISR_ITE); 200 201 /* Write data. */ 202 rv = bus_space_read_4(iot, ioh, I2C_ICR); 203 bus_space_write_4(iot, ioh, I2C_ICR, rv & ~ICR_START); 204 rv = bus_space_read_4(iot, ioh, I2C_ICR); 205 bus_space_write_4(iot, ioh, I2C_ICR, rv | ICR_STOP); 206 bus_space_write_4(iot, ioh, I2C_IDBR, value); 207 rv = bus_space_read_4(iot, ioh, I2C_ICR); 208 bus_space_write_4(iot, ioh, I2C_ICR, rv | ICR_TB); 209 210 timeout = 10000; 211 while ((bus_space_read_4(iot, ioh, I2C_ISR) & ISR_ITE) == 0) { 212 if (timeout-- == 0) 213 goto err; 214 delay(1); 215 } 216 if ((bus_space_read_4(iot, ioh, I2C_ISR) & ISR_ACKNAK) != 0) 217 goto err; 218 219 bus_space_write_4(iot, ioh, I2C_ISR, ISR_ITE); 220 221 rv = bus_space_read_4(iot, ioh, I2C_ICR); 222 bus_space_write_4(iot, ioh, I2C_ICR, rv & ~ICR_STOP); 223 224 return 0; 225 226 err: 227 if (tries-- >= 0) 228 goto retry; 229 230 bus_space_write_4(iot, ioh, I2C_ICR, ICR_UR); 231 bus_space_write_4(iot, ioh, I2C_ISAR, 0x00); 232 bus_space_write_4(iot, ioh, I2C_ISR, ISR_ITE); 233 bus_space_write_4(iot, ioh, I2C_ICR, ICR_IUE | ICR_SCLE); 234 235 return EIO; 236 } 237 238 /* 239 * XXX The quick_{read,write} opertions are untested! 240 */ 241 int 242 pxa2x0_i2c_quick(struct pxa2x0_i2c_softc *sc, u_char slave, u_char rw) 243 { 244 bus_space_tag_t iot = sc->sc_iot; 245 bus_space_handle_t ioh = sc->sc_ioh; 246 int timeout; 247 int tries = I2C_RETRY_COUNT; 248 uint32_t rv; 249 250 retry: 251 bus_space_write_4(iot, ioh, I2C_ICR, ICR_UR); 252 bus_space_write_4(iot, ioh, I2C_ISAR, 0x00); 253 bus_space_write_4(iot, ioh, I2C_ISR, ISR_ITE); 254 delay(1); 255 bus_space_write_4(iot, ioh, I2C_ICR, ICR_IUE | ICR_SCLE); 256 257 /* Write slave device address. */ 258 bus_space_write_4(iot, ioh, I2C_IDBR, (slave<<1) | (rw & 1)); 259 rv = bus_space_read_4(iot, ioh, I2C_ICR); 260 bus_space_write_4(iot, ioh, I2C_ICR, rv | ICR_START); 261 rv = bus_space_read_4(iot, ioh, I2C_ICR); 262 bus_space_write_4(iot, ioh, I2C_ICR, rv | ICR_STOP); 263 rv = bus_space_read_4(iot, ioh, I2C_ICR); 264 265 timeout = 10000; 266 while ((bus_space_read_4(iot, ioh, I2C_ISR) & ISR_ITE) == 0) { 267 if (timeout-- == 0) 268 goto err; 269 delay(1); 270 } 271 if ((bus_space_read_4(iot, ioh, I2C_ISR) & ISR_ACKNAK) != 0) 272 goto err; 273 274 bus_space_write_4(iot, ioh, I2C_ISR, ISR_ITE); 275 276 rv = bus_space_read_4(iot, ioh, I2C_ICR); 277 bus_space_write_4(iot, ioh, I2C_ICR, rv & ~ICR_STOP); 278 279 return 0; 280 281 err: 282 if (tries-- >= 0) 283 goto retry; 284 285 bus_space_write_4(iot, ioh, I2C_ICR, ICR_UR); 286 bus_space_write_4(iot, ioh, I2C_ISAR, 0x00); 287 bus_space_write_4(iot, ioh, I2C_ISR, ISR_ITE); 288 bus_space_write_4(iot, ioh, I2C_ICR, ICR_IUE | ICR_SCLE); 289 290 return EIO; 291 } 292 293 int 294 pxa2x0_i2c_write_2(struct pxa2x0_i2c_softc *sc, u_char slave, u_short value) 295 { 296 bus_space_tag_t iot = sc->sc_iot; 297 bus_space_handle_t ioh = sc->sc_ioh; 298 int timeout; 299 int tries = I2C_RETRY_COUNT; 300 uint32_t rv; 301 302 retry: 303 bus_space_write_4(iot, ioh, I2C_ICR, ICR_UR); 304 bus_space_write_4(iot, ioh, I2C_ISAR, 0x00); 305 bus_space_write_4(iot, ioh, I2C_ISR, ISR_ITE); 306 delay(1); 307 bus_space_write_4(iot, ioh, I2C_ICR, ICR_IUE | ICR_SCLE); 308 309 /* Write slave device address. */ 310 bus_space_write_4(iot, ioh, I2C_IDBR, (slave<<1)); 311 rv = bus_space_read_4(iot, ioh, I2C_ICR); 312 bus_space_write_4(iot, ioh, I2C_ICR, rv | ICR_START); 313 rv = bus_space_read_4(iot, ioh, I2C_ICR); 314 bus_space_write_4(iot, ioh, I2C_ICR, rv & ~ICR_STOP); 315 rv = bus_space_read_4(iot, ioh, I2C_ICR); 316 bus_space_write_4(iot, ioh, I2C_ICR, rv | ICR_TB); 317 318 timeout = 10000; 319 while ((bus_space_read_4(iot, ioh, I2C_ISR) & ISR_ITE) == 0) { 320 if (timeout-- == 0) 321 goto err; 322 delay(1); 323 } 324 if ((bus_space_read_4(iot, ioh, I2C_ISR) & ISR_ACKNAK) != 0) 325 goto err; 326 327 bus_space_write_4(iot, ioh, I2C_ISR, ISR_ITE); 328 329 /* Write upper 8 bits of data. */ 330 bus_space_write_4(iot, ioh, I2C_IDBR, (value >> 8) & 0xff); 331 rv = bus_space_read_4(iot, ioh, I2C_ICR); 332 bus_space_write_4(iot, ioh, I2C_ICR, rv & ~ICR_START); 333 rv = bus_space_read_4(iot, ioh, I2C_ICR); 334 bus_space_write_4(iot, ioh, I2C_ICR, rv & ~ICR_STOP); 335 rv = bus_space_read_4(iot, ioh, I2C_ICR); 336 bus_space_write_4(iot, ioh, I2C_ICR, rv | ICR_TB); 337 338 timeout = 10000; 339 while ((bus_space_read_4(iot, ioh, I2C_ISR) & ISR_ITE) == 0) { 340 if (timeout-- == 0) 341 goto err; 342 delay(1); 343 } 344 if ((bus_space_read_4(iot, ioh, I2C_ISR) & ISR_ACKNAK) != 0) 345 goto err; 346 347 bus_space_write_4(iot, ioh, I2C_ISR, ISR_ITE); 348 349 /* Write lower 8 bits of data. */ 350 bus_space_write_4(iot, ioh, I2C_IDBR, value & 0xff); 351 rv = bus_space_read_4(iot, ioh, I2C_ICR); 352 bus_space_write_4(iot, ioh, I2C_ICR, rv & ~ICR_START); 353 rv = bus_space_read_4(iot, ioh, I2C_ICR); 354 bus_space_write_4(iot, ioh, I2C_ICR, rv | ICR_STOP); 355 rv = bus_space_read_4(iot, ioh, I2C_ICR); 356 bus_space_write_4(iot, ioh, I2C_ICR, rv | ICR_TB); 357 358 timeout = 10000; 359 while ((bus_space_read_4(iot, ioh, I2C_ISR) & ISR_ITE) == 0) { 360 if (timeout-- == 0) 361 goto err; 362 delay(1); 363 } 364 if ((bus_space_read_4(iot, ioh, I2C_ISR) & ISR_ACKNAK) != 0) 365 goto err; 366 367 bus_space_write_4(iot, ioh, I2C_ISR, ISR_ITE); 368 369 rv = bus_space_read_4(iot, ioh, I2C_ICR); 370 bus_space_write_4(iot, ioh, I2C_ICR, rv & ~ICR_STOP); 371 372 return 0; 373 374 err: 375 if (tries-- >= 0) 376 goto retry; 377 378 bus_space_write_4(iot, ioh, I2C_ICR, ICR_UR); 379 bus_space_write_4(iot, ioh, I2C_ISAR, 0x00); 380 bus_space_write_4(iot, ioh, I2C_ISR, ISR_ITE); 381 bus_space_write_4(iot, ioh, I2C_ICR, ICR_IUE | ICR_SCLE); 382 383 return EIO; 384 } 385
Indexes created Sun Oct 19 22:09:57 GMT 2025