1 /* $NetBSD: i2c.c,v 1.23 2009/02/03 16:41:31 pgoyette 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 1.23 2009/02/03 16:41:31 pgoyette 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 63 int 64 iicbus_print(void *aux, const char *pnp) 65 { 66 67 if (pnp != NULL) 68 aprint_normal("iic at %s", pnp); 69 70 return (UNCONF); 71 } 72 73 static int 74 iic_print(void *aux, const char *pnp) 75 { 76 struct i2c_attach_args *ia = aux; 77 78 if (ia->ia_addr != (i2c_addr_t)-1) 79 aprint_normal(" addr 0x%x", ia->ia_addr); 80 81 return (UNCONF); 82 } 83 84 static int 85 iic_search(device_t parent, cfdata_t cf, const int *ldesc, void *aux) 86 { 87 struct iic_softc *sc = device_private(parent); 88 struct i2c_attach_args ia; 89 90 ia.ia_tag = sc->sc_tag; 91 ia.ia_addr = cf->cf_loc[IICCF_ADDR]; 92 ia.ia_size = cf->cf_loc[IICCF_SIZE]; 93 ia.ia_type = sc->sc_type; 94 95 if (config_match(parent, cf, &ia) > 0) 96 config_attach(parent, cf, &ia, iic_print); 97 98 return (0); 99 } 100 101 static int 102 iic_match(device_t parent, cfdata_t cf, void *aux) 103 { 104 105 return (1); 106 } 107 108 static void 109 iic_attach(device_t parent, device_t self, void *aux) 110 { 111 struct iic_softc *sc = device_private(self); 112 struct i2cbus_attach_args *iba = aux; 113 i2c_tag_t ic; 114 int rv; 115 116 aprint_naive(": I2C bus\n"); 117 aprint_normal(": I2C bus\n"); 118 119 sc->sc_tag = iba->iba_tag; 120 sc->sc_type = iba->iba_type; 121 ic = sc->sc_tag; 122 ic->ic_devname = device_xname(self); 123 124 LIST_INIT(&(sc->sc_tag->ic_list)); 125 LIST_INIT(&(sc->sc_tag->ic_proc_list)); 126 127 rv = kthread_create(PRI_NONE, 0, NULL, iic_smbus_intr_thread, 128 ic, &ic->ic_intr_thread, "%s", ic->ic_devname); 129 if (rv) 130 aprint_error_dev(self, "unable to create intr thread\n"); 131 132 #if I2C_SCAN 133 if (sc->sc_type == I2C_TYPE_SMBUS) { 134 int err; 135 int found = 0; 136 i2c_addr_t addr; 137 uint8_t val; 138 139 for (addr = 0x09; addr < 0x78; addr++) { 140 /* 141 * Skip certain i2c addresses: 142 * 0x00 General Call / START 143 * 0x01 CBUS Address 144 * 0x02 Different Bus format 145 * 0x03 - 0x07 Reserved 146 * 0x08 Host Address 147 * 0x0c Alert Response Address 148 * 0x28 ACCESS.Bus host 149 * 0x37 ACCESS.Bus default address 150 * 0x48 - 0x4b Prototypes 151 * 0x61 Device Default Address 152 * 0x78 - 0x7b 10-bit addresses 153 * 0x7c - 0x7f Reserved 154 * 155 * Some of these are skipped by judicious selection 156 * of the range of the above for (;;) statement. 157 * 158 * if (addr <= 0x08 || addr >= 0x78) 159 * continue; 160 */ 161 if (addr == 0x0c || addr == 0x28 || addr == 0x37 || 162 addr == 0x61 || (addr & 0x7c) == 0x48) 163 continue; 164 165 iic_acquire_bus(ic, 0); 166 /* 167 * Use SMBus quick_write command to detect most 168 * addresses; should avoid hanging the bus on 169 * some write-only devices (like clocks that show 170 * up at address 0x69) 171 * 172 * XXX The quick_write() is allegedly known to 173 * XXX corrupt the Atmel AT24RF08 EEPROM found 174 * XXX on some IBM Thinkpads! 175 */ 176 if ((addr & 0xf8) == 0x30 || 177 (addr & 0xf0) == 0x50) 178 err = iic_smbus_receive_byte(ic, addr, &val, 0); 179 else 180 err = iic_smbus_quick_write(ic, addr, 0); 181 if (err == 0) { 182 if (found == 0) 183 aprint_normal("%s: devices at", 184 ic->ic_devname); 185 found++; 186 aprint_normal(" 0x%02x", addr); 187 } 188 iic_release_bus(ic, 0); 189 } 190 if (found == 0) 191 aprint_normal("%s: no devices found", ic->ic_devname); 192 aprint_normal("\n"); 193 } 194 #endif 195 196 if (!pmf_device_register(self, NULL, NULL)) 197 aprint_error_dev(self, "couldn't establish power handler\n"); 198 199 /* 200 * Attach all i2c devices described in the kernel 201 * configuration file. 202 */ 203 config_search_ia(iic_search, self, "iic", NULL); 204 } 205 206 static void 207 iic_smbus_intr_thread(void *aux) 208 { 209 i2c_tag_t ic; 210 struct ic_intr_list *il; 211 int rv; 212 213 ic = (i2c_tag_t)aux; 214 ic->ic_running = 1; 215 ic->ic_pending = 0; 216 217 while (ic->ic_running) { 218 if (ic->ic_pending == 0) 219 rv = tsleep(ic, PZERO, "iicintr", hz); 220 if (ic->ic_pending > 0) { 221 LIST_FOREACH(il, &(ic->ic_proc_list), il_next) { 222 (*il->il_intr)(il->il_intrarg); 223 } 224 ic->ic_pending--; 225 } 226 } 227 228 kthread_exit(0); 229 } 230 231 void * 232 iic_smbus_intr_establish(i2c_tag_t ic, int (*intr)(void *), void *intrarg) 233 { 234 struct ic_intr_list *il; 235 236 il = malloc(sizeof(struct ic_intr_list), M_DEVBUF, M_WAITOK); 237 if (il == NULL) 238 return NULL; 239 240 il->il_intr = intr; 241 il->il_intrarg = intrarg; 242 243 LIST_INSERT_HEAD(&(ic->ic_list), il, il_next); 244 245 return il; 246 } 247 248 void 249 iic_smbus_intr_disestablish(i2c_tag_t ic, void *hdl) 250 { 251 struct ic_intr_list *il; 252 253 il = (struct ic_intr_list *)hdl; 254 255 LIST_REMOVE(il, il_next); 256 free(il, M_DEVBUF); 257 258 return; 259 } 260 261 void * 262 iic_smbus_intr_establish_proc(i2c_tag_t ic, int (*intr)(void *), void *intrarg) 263 { 264 struct ic_intr_list *il; 265 266 il = malloc(sizeof(struct ic_intr_list), M_DEVBUF, M_WAITOK); 267 if (il == NULL) 268 return NULL; 269 270 il->il_intr = intr; 271 il->il_intrarg = intrarg; 272 273 LIST_INSERT_HEAD(&(ic->ic_proc_list), il, il_next); 274 275 return il; 276 } 277 278 void 279 iic_smbus_intr_disestablish_proc(i2c_tag_t ic, void *hdl) 280 { 281 struct ic_intr_list *il; 282 283 il = (struct ic_intr_list *)hdl; 284 285 LIST_REMOVE(il, il_next); 286 free(il, M_DEVBUF); 287 288 return; 289 } 290 291 int 292 iic_smbus_intr(i2c_tag_t ic) 293 { 294 struct ic_intr_list *il; 295 296 LIST_FOREACH(il, &(ic->ic_list), il_next) { 297 (*il->il_intr)(il->il_intrarg); 298 } 299 300 ic->ic_pending++; 301 wakeup(ic); 302 303 return 1; 304 } 305 306 CFATTACH_DECL_NEW(iic, sizeof(struct iic_softc), 307 iic_match, iic_attach, NULL, NULL); 308