1 /* $NetBSD: i2c.c,v 1.25 2010/03/01 17:35:21 njoly Exp $ */ 2 3 /* 4 * Copyright (c) 2003 Wasabi Systems, Inc. 5 * All rights reserved. 6 * 7 * Written by 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/cdefs.h> 39 __KERNEL_RCSID(0, "$NetBSD: i2c.c,v 1.25 2010/03/01 17:35:21 njoly Exp $"); 40 41 #include <sys/param.h> 42 #include <sys/systm.h> 43 #include <sys/device.h> 44 #include <sys/event.h> 45 #include <sys/conf.h> 46 #include <sys/malloc.h> 47 #include <sys/kthread.h> 48 #include <sys/proc.h> 49 #include <sys/kernel.h> 50 51 #include <dev/i2c/i2cvar.h> 52 53 #include "locators.h" 54 #include <opt_i2cbus.h> 55 56 struct iic_softc { 57 i2c_tag_t sc_tag; 58 int sc_type; 59 }; 60 61 static void iic_smbus_intr_thread(void *); 62 static void iic_fill_compat(struct i2c_attach_args*, const char*, 63 size_t, char **); 64 65 int 66 iicbus_print(void *aux, const char *pnp) 67 { 68 69 if (pnp != NULL) 70 aprint_normal("iic at %s", pnp); 71 72 return (UNCONF); 73 } 74 75 static int 76 iic_print_direct(void *aux, const char *pnp) 77 { 78 struct i2c_attach_args *ia = aux; 79 80 if (pnp != NULL) 81 aprint_normal("%s at %s addr 0x%02x", ia->ia_name, pnp, 82 ia->ia_addr); 83 else 84 aprint_normal(" addr 0x%02x", ia->ia_addr); 85 86 return UNCONF; 87 } 88 89 static int 90 iic_print(void *aux, const char *pnp) 91 { 92 struct i2c_attach_args *ia = aux; 93 94 if (ia->ia_addr != (i2c_addr_t)-1) 95 aprint_normal(" addr 0x%x", ia->ia_addr); 96 97 return (UNCONF); 98 } 99 100 static int 101 iic_search(device_t parent, cfdata_t cf, const int *ldesc, void *aux) 102 { 103 struct iic_softc *sc = device_private(parent); 104 struct i2c_attach_args ia; 105 106 ia.ia_tag = sc->sc_tag; 107 ia.ia_addr = cf->cf_loc[IICCF_ADDR]; 108 ia.ia_size = cf->cf_loc[IICCF_SIZE]; 109 ia.ia_type = sc->sc_type; 110 111 ia.ia_name = NULL; 112 ia.ia_ncompat = 0; 113 ia.ia_compat = NULL; 114 115 if (config_match(parent, cf, &ia) > 0) 116 config_attach(parent, cf, &ia, iic_print); 117 118 return (0); 119 } 120 121 static int 122 iic_match(device_t parent, cfdata_t cf, void *aux) 123 { 124 125 return (1); 126 } 127 128 static void 129 iic_attach(device_t parent, device_t self, void *aux) 130 { 131 struct iic_softc *sc = device_private(self); 132 struct i2cbus_attach_args *iba = aux; 133 prop_array_t child_devices; 134 char *buf; 135 i2c_tag_t ic; 136 int rv; 137 138 aprint_naive(": I2C bus\n"); 139 aprint_normal(": I2C bus\n"); 140 141 sc->sc_tag = iba->iba_tag; 142 sc->sc_type = iba->iba_type; 143 ic = sc->sc_tag; 144 ic->ic_devname = device_xname(self); 145 146 LIST_INIT(&(sc->sc_tag->ic_list)); 147 LIST_INIT(&(sc->sc_tag->ic_proc_list)); 148 149 rv = kthread_create(PRI_NONE, 0, NULL, iic_smbus_intr_thread, 150 ic, &ic->ic_intr_thread, "%s", ic->ic_devname); 151 if (rv) 152 aprint_error_dev(self, "unable to create intr thread\n"); 153 154 #if I2C_SCAN 155 if (sc->sc_type == I2C_TYPE_SMBUS) { 156 int err; 157 int found = 0; 158 i2c_addr_t addr; 159 uint8_t val; 160 161 for (addr = 0x09; addr < 0x78; addr++) { 162 /* 163 * Skip certain i2c addresses: 164 * 0x00 General Call / START 165 * 0x01 CBUS Address 166 * 0x02 Different Bus format 167 * 0x03 - 0x07 Reserved 168 * 0x08 Host Address 169 * 0x0c Alert Response Address 170 * 0x28 ACCESS.Bus host 171 * 0x37 ACCESS.Bus default address 172 * 0x48 - 0x4b Prototypes 173 * 0x61 Device Default Address 174 * 0x78 - 0x7b 10-bit addresses 175 * 0x7c - 0x7f Reserved 176 * 177 * Some of these are skipped by judicious selection 178 * of the range of the above for (;;) statement. 179 * 180 * if (addr <= 0x08 || addr >= 0x78) 181 * continue; 182 */ 183 if (addr == 0x0c || addr == 0x28 || addr == 0x37 || 184 addr == 0x61 || (addr & 0x7c) == 0x48) 185 continue; 186 187 iic_acquire_bus(ic, 0); 188 /* 189 * Use SMBus quick_write command to detect most 190 * addresses; should avoid hanging the bus on 191 * some write-only devices (like clocks that show 192 * up at address 0x69) 193 * 194 * XXX The quick_write() is allegedly known to 195 * XXX corrupt the Atmel AT24RF08 EEPROM found 196 * XXX on some IBM Thinkpads! 197 */ 198 if ((addr & 0xf8) == 0x30 || 199 (addr & 0xf0) == 0x50) 200 err = iic_smbus_receive_byte(ic, addr, &val, 0); 201 else 202 err = iic_smbus_quick_write(ic, addr, 0); 203 if (err == 0) { 204 if (found == 0) 205 aprint_normal("%s: devices at", 206 ic->ic_devname); 207 found++; 208 aprint_normal(" 0x%02x", addr); 209 } 210 iic_release_bus(ic, 0); 211 } 212 if (found == 0) 213 aprint_normal("%s: no devices found", ic->ic_devname); 214 aprint_normal("\n"); 215 } 216 #endif 217 218 if (!pmf_device_register(self, NULL, NULL)) 219 aprint_error_dev(self, "couldn't establish power handler\n"); 220 221 child_devices = prop_dictionary_get(device_properties(parent), 222 "i2c-child-devices"); 223 if (child_devices) { 224 unsigned int i, count; 225 prop_dictionary_t dev; 226 prop_data_t cdata; 227 uint32_t addr, size; 228 uint64_t cookie; 229 const char *name; 230 struct i2c_attach_args ia; 231 int loc[2]; 232 233 memset(loc, 0, sizeof loc); 234 count = prop_array_count(child_devices); 235 for (i = 0; i < count; i++) { 236 dev = prop_array_get(child_devices, i); 237 if (!dev) continue; 238 if (!prop_dictionary_get_cstring_nocopy( 239 dev, "name", &name)) 240 continue; 241 if (!prop_dictionary_get_uint32(dev, "addr", &addr)) 242 continue; 243 if (!prop_dictionary_get_uint64(dev, "cookie", &cookie)) 244 cookie = 0; 245 loc[0] = addr; 246 if (prop_dictionary_get_uint32(dev, "size", &size)) 247 loc[1] = size; 248 else 249 loc[1] = -1; 250 251 memset(&ia, 0, sizeof ia); 252 ia.ia_addr = addr; 253 ia.ia_type = sc->sc_type; 254 ia.ia_tag = ic; 255 ia.ia_name = name; 256 ia.ia_cookie = cookie; 257 258 buf = NULL; 259 cdata = prop_dictionary_get(dev, "compatible"); 260 if (cdata) 261 iic_fill_compat(&ia, 262 prop_data_data_nocopy(cdata), 263 prop_data_size(cdata), &buf); 264 265 config_found_sm_loc(self, "iic", loc, &ia, 266 iic_print_direct, NULL); 267 268 if (ia.ia_compat) 269 free(ia.ia_compat, M_TEMP); 270 if (buf) 271 free(buf, M_TEMP); 272 } 273 } else { 274 /* 275 * Attach all i2c devices described in the kernel 276 * configuration file. 277 */ 278 config_search_ia(iic_search, self, "iic", NULL); 279 } 280 } 281 282 static void 283 iic_smbus_intr_thread(void *aux) 284 { 285 i2c_tag_t ic; 286 struct ic_intr_list *il; 287 int rv; 288 289 ic = (i2c_tag_t)aux; 290 ic->ic_running = 1; 291 ic->ic_pending = 0; 292 293 while (ic->ic_running) { 294 if (ic->ic_pending == 0) 295 rv = tsleep(ic, PZERO, "iicintr", hz); 296 if (ic->ic_pending > 0) { 297 LIST_FOREACH(il, &(ic->ic_proc_list), il_next) { 298 (*il->il_intr)(il->il_intrarg); 299 } 300 ic->ic_pending--; 301 } 302 } 303 304 kthread_exit(0); 305 } 306 307 void * 308 iic_smbus_intr_establish(i2c_tag_t ic, int (*intr)(void *), void *intrarg) 309 { 310 struct ic_intr_list *il; 311 312 il = malloc(sizeof(struct ic_intr_list), M_DEVBUF, M_WAITOK); 313 if (il == NULL) 314 return NULL; 315 316 il->il_intr = intr; 317 il->il_intrarg = intrarg; 318 319 LIST_INSERT_HEAD(&(ic->ic_list), il, il_next); 320 321 return il; 322 } 323 324 void 325 iic_smbus_intr_disestablish(i2c_tag_t ic, void *hdl) 326 { 327 struct ic_intr_list *il; 328 329 il = (struct ic_intr_list *)hdl; 330 331 LIST_REMOVE(il, il_next); 332 free(il, M_DEVBUF); 333 334 return; 335 } 336 337 void * 338 iic_smbus_intr_establish_proc(i2c_tag_t ic, int (*intr)(void *), void *intrarg) 339 { 340 struct ic_intr_list *il; 341 342 il = malloc(sizeof(struct ic_intr_list), M_DEVBUF, M_WAITOK); 343 if (il == NULL) 344 return NULL; 345 346 il->il_intr = intr; 347 il->il_intrarg = intrarg; 348 349 LIST_INSERT_HEAD(&(ic->ic_proc_list), il, il_next); 350 351 return il; 352 } 353 354 void 355 iic_smbus_intr_disestablish_proc(i2c_tag_t ic, void *hdl) 356 { 357 struct ic_intr_list *il; 358 359 il = (struct ic_intr_list *)hdl; 360 361 LIST_REMOVE(il, il_next); 362 free(il, M_DEVBUF); 363 364 return; 365 } 366 367 int 368 iic_smbus_intr(i2c_tag_t ic) 369 { 370 struct ic_intr_list *il; 371 372 LIST_FOREACH(il, &(ic->ic_list), il_next) { 373 (*il->il_intr)(il->il_intrarg); 374 } 375 376 ic->ic_pending++; 377 wakeup(ic); 378 379 return 1; 380 } 381 382 static void 383 iic_fill_compat(struct i2c_attach_args *ia, const char *compat, size_t len, 384 char **buffer) 385 { 386 int count, i; 387 const char *c, *start, **ptr; 388 389 *buffer = NULL; 390 for (i = count = 0, c = compat; i < len; i++, c++) 391 if (*c == 0) 392 count++; 393 count += 2; 394 ptr = malloc(sizeof(char*)*count, M_TEMP, M_WAITOK); 395 if (!ptr) return; 396 397 for (i = count = 0, start = c = compat; i < len; i++, c++) { 398 if (*c == 0) { 399 ptr[count++] = start; 400 start = c+1; 401 } 402 } 403 if (start < compat+len) { 404 /* last string not 0 terminated */ 405 size_t l = c-start; 406 *buffer = malloc(l+1, M_TEMP, M_WAITOK); 407 memcpy(*buffer, start, l); 408 (*buffer)[l] = 0; 409 ptr[count++] = *buffer; 410 } 411 ptr[count] = NULL; 412 413 ia->ia_compat = ptr; 414 ia->ia_ncompat = count; 415 } 416 417 int 418 iic_compat_match(struct i2c_attach_args *ia, const char ** compats) 419 { 420 int i; 421 422 for (; compats && *compats; compats++) { 423 for (i = 0; i < ia->ia_ncompat; i++) { 424 if (strcmp(*compats, ia->ia_compat[i]) == 0) 425 return 1; 426 } 427 } 428 return 0; 429 } 430 431 432 CFATTACH_DECL_NEW(iic, sizeof(struct iic_softc), 433 iic_match, iic_attach, NULL, NULL); 434