1 /* 2 * Copyright (C) 2009 Sergey Kubushyn <ksi@koi8.net> 3 * 4 * (C) Copyright 2012 5 * Heiko Schocher, DENX Software Engineering, hs@denx.de. 6 * 7 * Multibus/multiadapter I2C core functions (wrappers) 8 * 9 * SPDX-License-Identifier: GPL-2.0+ 10 */ 11 #include <common.h> 12 #include <i2c.h> 13 14 struct i2c_adapter *i2c_get_adapter(int index) 15 { 16 struct i2c_adapter *i2c_adap_p = ll_entry_start(struct i2c_adapter, 17 i2c); 18 int max = ll_entry_count(struct i2c_adapter, i2c); 19 int i; 20 21 if (index >= max) { 22 printf("Error, wrong i2c adapter %d max %d possible\n", 23 index, max); 24 return i2c_adap_p; 25 } 26 if (index == 0) 27 return i2c_adap_p; 28 29 for (i = 0; i < index; i++) 30 i2c_adap_p++; 31 32 return i2c_adap_p; 33 } 34 35 #if !defined(CONFIG_SYS_I2C_DIRECT_BUS) 36 struct i2c_bus_hose i2c_bus[CONFIG_SYS_NUM_I2C_BUSES] = 37 CONFIG_SYS_I2C_BUSES; 38 #endif 39 40 DECLARE_GLOBAL_DATA_PTR; 41 42 void i2c_reloc_fixup(void) 43 { 44 #if defined(CONFIG_NEEDS_MANUAL_RELOC) 45 struct i2c_adapter *i2c_adap_p = ll_entry_start(struct i2c_adapter, 46 i2c); 47 struct i2c_adapter *tmp = i2c_adap_p; 48 int max = ll_entry_count(struct i2c_adapter, i2c); 49 int i; 50 unsigned long addr; 51 52 if (gd->reloc_off == 0) 53 return; 54 55 for (i = 0; i < max; i++) { 56 /* adapter itself */ 57 addr = (unsigned long)i2c_adap_p; 58 addr += gd->reloc_off; 59 i2c_adap_p = (struct i2c_adapter *)addr; 60 /* i2c_init() */ 61 addr = (unsigned long)i2c_adap_p->init; 62 addr += gd->reloc_off; 63 i2c_adap_p->init = (void (*)(int, int))addr; 64 /* i2c_probe() */ 65 addr = (unsigned long)i2c_adap_p->probe; 66 addr += gd->reloc_off; 67 i2c_adap_p->probe = (int (*)(uint8_t))addr; 68 /* i2c_read() */ 69 addr = (unsigned long)i2c_adap_p->read; 70 addr += gd->reloc_off; 71 i2c_adap_p->read = (int (*)(uint8_t, uint, int, uint8_t *, 72 int))addr; 73 /* i2c_write() */ 74 addr = (unsigned long)i2c_adap_p->write; 75 addr += gd->reloc_off; 76 i2c_adap_p->write = (int (*)(uint8_t, uint, int, uint8_t *, 77 int))addr; 78 /* i2c_set_bus_speed() */ 79 addr = (unsigned long)i2c_adap_p->set_bus_speed; 80 addr += gd->reloc_off; 81 i2c_adap_p->set_bus_speed = (uint (*)(uint))addr; 82 /* name */ 83 addr = (unsigned long)i2c_adap_p->name; 84 addr += gd->reloc_off; 85 i2c_adap_p->name = (char *)addr; 86 tmp++; 87 i2c_adap_p = tmp; 88 } 89 #endif 90 } 91 92 #ifndef CONFIG_SYS_I2C_DIRECT_BUS 93 /* 94 * i2c_mux_set() 95 * ------------- 96 * 97 * This turns on the given channel on I2C multiplexer chip connected to 98 * a given I2C adapter directly or via other multiplexers. In the latter 99 * case the entire multiplexer chain must be initialized first starting 100 * with the one connected directly to the adapter. When disabling a chain 101 * muxes must be programmed in reverse order, starting with the one 102 * farthest from the adapter. 103 * 104 * mux_id is the multiplexer chip type from defined in i2c.h. So far only 105 * NXP (Philips) PCA954x multiplexers are supported. Switches are NOT 106 * supported (anybody uses them?) 107 */ 108 109 static int i2c_mux_set(struct i2c_adapter *adap, int mux_id, int chip, 110 int channel) 111 { 112 uint8_t buf; 113 int ret; 114 115 /* channel < 0 - turn off the mux */ 116 if (channel < 0) { 117 buf = 0; 118 ret = adap->write(adap, chip, 0, 0, &buf, 1); 119 if (ret) 120 printf("%s: Could not turn off the mux.\n", __func__); 121 return ret; 122 } 123 124 switch (mux_id) { 125 case I2C_MUX_PCA9540_ID: 126 case I2C_MUX_PCA9542_ID: 127 if (channel > 1) 128 return -1; 129 buf = (uint8_t)((channel & 0x01) | (1 << 2)); 130 break; 131 case I2C_MUX_PCA9544_ID: 132 if (channel > 3) 133 return -1; 134 buf = (uint8_t)((channel & 0x03) | (1 << 2)); 135 break; 136 case I2C_MUX_PCA9547_ID: 137 if (channel > 7) 138 return -1; 139 buf = (uint8_t)((channel & 0x07) | (1 << 3)); 140 break; 141 case I2C_MUX_PCA9548_ID: 142 if (channel > 7) 143 return -1; 144 buf = (uint8_t)(0x01 << channel); 145 break; 146 default: 147 printf("%s: wrong mux id: %d\n", __func__, mux_id); 148 return -1; 149 } 150 151 ret = adap->write(adap, chip, 0, 0, &buf, 1); 152 if (ret) 153 printf("%s: could not set mux: id: %d chip: %x channel: %d\n", 154 __func__, mux_id, chip, channel); 155 return ret; 156 } 157 158 static int i2c_mux_set_all(void) 159 { 160 struct i2c_bus_hose *i2c_bus_tmp = &i2c_bus[I2C_BUS]; 161 int i; 162 163 /* Connect requested bus if behind muxes */ 164 if (i2c_bus_tmp->next_hop[0].chip != 0) { 165 /* Set all muxes along the path to that bus */ 166 for (i = 0; i < CONFIG_SYS_I2C_MAX_HOPS; i++) { 167 int ret; 168 169 if (i2c_bus_tmp->next_hop[i].chip == 0) 170 break; 171 172 ret = i2c_mux_set(I2C_ADAP, 173 i2c_bus_tmp->next_hop[i].mux.id, 174 i2c_bus_tmp->next_hop[i].chip, 175 i2c_bus_tmp->next_hop[i].channel); 176 if (ret != 0) 177 return ret; 178 } 179 } 180 return 0; 181 } 182 183 static int i2c_mux_disconnet_all(void) 184 { 185 struct i2c_bus_hose *i2c_bus_tmp = &i2c_bus[I2C_BUS]; 186 int i; 187 uint8_t buf; 188 189 if (I2C_ADAP->init_done == 0) 190 return 0; 191 192 /* Disconnect current bus (turn off muxes if any) */ 193 if ((i2c_bus_tmp->next_hop[0].chip != 0) && 194 (I2C_ADAP->init_done != 0)) { 195 i = CONFIG_SYS_I2C_MAX_HOPS; 196 do { 197 uint8_t chip; 198 int ret; 199 200 chip = i2c_bus_tmp->next_hop[--i].chip; 201 if (chip == 0) 202 continue; 203 204 ret = I2C_ADAP->write(I2C_ADAP, chip, 0, 0, &buf, 1); 205 if (ret != 0) { 206 printf("i2c: mux diconnect error\n"); 207 return ret; 208 } 209 } while (i > 0); 210 } 211 212 return 0; 213 } 214 #endif 215 216 /* 217 * i2c_init_bus(): 218 * --------------- 219 * 220 * Initializes one bus. Will initialize the parent adapter. No current bus 221 * changes, no mux (if any) setup. 222 */ 223 static void i2c_init_bus(unsigned int bus_no, int speed, int slaveaddr) 224 { 225 if (bus_no >= CONFIG_SYS_NUM_I2C_BUSES) 226 return; 227 228 I2C_ADAP->init(I2C_ADAP, speed, slaveaddr); 229 230 if (gd->flags & GD_FLG_RELOC) { 231 I2C_ADAP->init_done = 1; 232 I2C_ADAP->speed = speed; 233 I2C_ADAP->slaveaddr = slaveaddr; 234 } 235 } 236 237 /* implement possible board specific board init */ 238 static void __def_i2c_init_board(void) 239 { 240 } 241 void i2c_init_board(void) 242 __attribute__((weak, alias("__def_i2c_init_board"))); 243 244 /* 245 * i2c_init_all(): 246 * 247 * not longer needed, will deleted. Actual init the SPD_BUS 248 * for compatibility. 249 * i2c_adap[] must be initialized beforehead with function pointers and 250 * data, including speed and slaveaddr. 251 */ 252 void i2c_init_all(void) 253 { 254 i2c_init_board(); 255 i2c_set_bus_num(CONFIG_SYS_SPD_BUS_NUM); 256 return; 257 } 258 259 /* 260 * i2c_get_bus_num(): 261 * ------------------ 262 * 263 * Returns index of currently active I2C bus. Zero-based. 264 */ 265 unsigned int i2c_get_bus_num(void) 266 { 267 return gd->cur_i2c_bus; 268 } 269 270 /* 271 * i2c_set_bus_num(): 272 * ------------------ 273 * 274 * Change the active I2C bus. Subsequent read/write calls will 275 * go to this one. Sets all of the muxes in a proper condition 276 * if that bus is behind muxes. 277 * If previously selected bus is behind the muxes turns off all the 278 * muxes along the path to that bus. 279 * 280 * bus - bus index, zero based 281 * 282 * Returns: 0 on success, not 0 on failure 283 */ 284 int i2c_set_bus_num(unsigned int bus) 285 { 286 int max; 287 288 if ((bus == I2C_BUS) && (I2C_ADAP->init_done > 0)) 289 return 0; 290 291 #ifndef CONFIG_SYS_I2C_DIRECT_BUS 292 if (bus >= CONFIG_SYS_NUM_I2C_BUSES) 293 return -1; 294 #endif 295 296 max = ll_entry_count(struct i2c_adapter, i2c); 297 if (I2C_ADAPTER(bus) >= max) { 298 printf("Error, wrong i2c adapter %d max %d possible\n", 299 I2C_ADAPTER(bus), max); 300 return -2; 301 } 302 303 #ifndef CONFIG_SYS_I2C_DIRECT_BUS 304 i2c_mux_disconnet_all(); 305 #endif 306 307 gd->cur_i2c_bus = bus; 308 if (I2C_ADAP->init_done == 0) 309 i2c_init_bus(bus, I2C_ADAP->speed, I2C_ADAP->slaveaddr); 310 311 #ifndef CONFIG_SYS_I2C_DIRECT_BUS 312 i2c_mux_set_all(); 313 #endif 314 return 0; 315 } 316 317 /* 318 * Probe the given I2C chip address. Returns 0 if a chip responded, 319 * not 0 on failure. 320 */ 321 int i2c_probe(uint8_t chip) 322 { 323 return I2C_ADAP->probe(I2C_ADAP, chip); 324 } 325 326 /* 327 * Read/Write interface: 328 * chip: I2C chip address, range 0..127 329 * addr: Memory (register) address within the chip 330 * alen: Number of bytes to use for addr (typically 1, 2 for larger 331 * memories, 0 for register type devices with only one 332 * register) 333 * buffer: Where to read/write the data 334 * len: How many bytes to read/write 335 * 336 * Returns: 0 on success, not 0 on failure 337 */ 338 int i2c_read(uint8_t chip, unsigned int addr, int alen, 339 uint8_t *buffer, int len) 340 { 341 return I2C_ADAP->read(I2C_ADAP, chip, addr, alen, buffer, len); 342 } 343 344 int i2c_write(uint8_t chip, unsigned int addr, int alen, 345 uint8_t *buffer, int len) 346 { 347 return I2C_ADAP->write(I2C_ADAP, chip, addr, alen, buffer, len); 348 } 349 350 unsigned int i2c_set_bus_speed(unsigned int speed) 351 { 352 unsigned int ret; 353 354 if (I2C_ADAP->set_bus_speed == NULL) 355 return 0; 356 ret = I2C_ADAP->set_bus_speed(I2C_ADAP, speed); 357 if (gd->flags & GD_FLG_RELOC) 358 I2C_ADAP->speed = ret; 359 360 return ret; 361 } 362 363 unsigned int i2c_get_bus_speed(void) 364 { 365 struct i2c_adapter *cur = I2C_ADAP; 366 return cur->speed; 367 } 368 369 uint8_t i2c_reg_read(uint8_t addr, uint8_t reg) 370 { 371 uint8_t buf; 372 373 #ifdef CONFIG_8xx 374 /* MPC8xx needs this. Maybe one day we can get rid of it. */ 375 /* maybe it is now the time for it ... */ 376 i2c_set_bus_num(i2c_get_bus_num()); 377 #endif 378 i2c_read(addr, reg, 1, &buf, 1); 379 380 #ifdef DEBUG 381 printf("%s: bus=%d addr=0x%02x, reg=0x%02x, val=0x%02x\n", 382 __func__, i2c_get_bus_num(), addr, reg, buf); 383 #endif 384 385 return buf; 386 } 387 388 void i2c_reg_write(uint8_t addr, uint8_t reg, uint8_t val) 389 { 390 #ifdef CONFIG_8xx 391 /* MPC8xx needs this. Maybe one day we can get rid of it. */ 392 /* maybe it is now the time for it ... */ 393 i2c_set_bus_num(i2c_get_bus_num()); 394 #endif 395 396 #ifdef DEBUG 397 printf("%s: bus=%d addr=0x%02x, reg=0x%02x, val=0x%02x\n", 398 __func__, i2c_get_bus_num(), addr, reg, val); 399 #endif 400 401 i2c_write(addr, reg, 1, &val, 1); 402 } 403 404 void __i2c_init(int speed, int slaveaddr) 405 { 406 i2c_init_bus(i2c_get_bus_num(), speed, slaveaddr); 407 } 408 void i2c_init(int speed, int slaveaddr) 409 __attribute__((weak, alias("__i2c_init"))); 410