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 default: 142 printf("%s: wrong mux id: %d\n", __func__, mux_id); 143 return -1; 144 } 145 146 ret = adap->write(adap, chip, 0, 0, &buf, 1); 147 if (ret) 148 printf("%s: could not set mux: id: %d chip: %x channel: %d\n", 149 __func__, mux_id, chip, channel); 150 return ret; 151 } 152 153 static int i2c_mux_set_all(void) 154 { 155 struct i2c_bus_hose *i2c_bus_tmp = &i2c_bus[I2C_BUS]; 156 int i; 157 158 /* Connect requested bus if behind muxes */ 159 if (i2c_bus_tmp->next_hop[0].chip != 0) { 160 /* Set all muxes along the path to that bus */ 161 for (i = 0; i < CONFIG_SYS_I2C_MAX_HOPS; i++) { 162 int ret; 163 164 if (i2c_bus_tmp->next_hop[i].chip == 0) 165 break; 166 167 ret = i2c_mux_set(I2C_ADAP, 168 i2c_bus_tmp->next_hop[i].mux.id, 169 i2c_bus_tmp->next_hop[i].chip, 170 i2c_bus_tmp->next_hop[i].channel); 171 if (ret != 0) 172 return ret; 173 } 174 } 175 return 0; 176 } 177 178 static int i2c_mux_disconnet_all(void) 179 { 180 struct i2c_bus_hose *i2c_bus_tmp = &i2c_bus[I2C_BUS]; 181 int i; 182 uint8_t buf; 183 184 if (I2C_ADAP->init_done == 0) 185 return 0; 186 187 /* Disconnect current bus (turn off muxes if any) */ 188 if ((i2c_bus_tmp->next_hop[0].chip != 0) && 189 (I2C_ADAP->init_done != 0)) { 190 i = CONFIG_SYS_I2C_MAX_HOPS; 191 do { 192 uint8_t chip; 193 int ret; 194 195 chip = i2c_bus_tmp->next_hop[--i].chip; 196 if (chip == 0) 197 continue; 198 199 ret = I2C_ADAP->write(I2C_ADAP, chip, 0, 0, &buf, 1); 200 if (ret != 0) { 201 printf("i2c: mux diconnect error\n"); 202 return ret; 203 } 204 } while (i > 0); 205 } 206 207 return 0; 208 } 209 #endif 210 211 /* 212 * i2c_init_bus(): 213 * --------------- 214 * 215 * Initializes one bus. Will initialize the parent adapter. No current bus 216 * changes, no mux (if any) setup. 217 */ 218 static void i2c_init_bus(unsigned int bus_no, int speed, int slaveaddr) 219 { 220 if (bus_no >= CONFIG_SYS_NUM_I2C_BUSES) 221 return; 222 223 I2C_ADAP->init(I2C_ADAP, speed, slaveaddr); 224 225 if (gd->flags & GD_FLG_RELOC) { 226 I2C_ADAP->init_done = 1; 227 I2C_ADAP->speed = speed; 228 I2C_ADAP->slaveaddr = slaveaddr; 229 } 230 } 231 232 /* implement possible board specific board init */ 233 static void __def_i2c_init_board(void) 234 { 235 } 236 void i2c_init_board(void) 237 __attribute__((weak, alias("__def_i2c_init_board"))); 238 239 /* 240 * i2c_init_all(): 241 * 242 * not longer needed, will deleted. Actual init the SPD_BUS 243 * for compatibility. 244 * i2c_adap[] must be initialized beforehead with function pointers and 245 * data, including speed and slaveaddr. 246 */ 247 void i2c_init_all(void) 248 { 249 i2c_init_board(); 250 i2c_set_bus_num(CONFIG_SYS_SPD_BUS_NUM); 251 return; 252 } 253 254 /* 255 * i2c_get_bus_num(): 256 * ------------------ 257 * 258 * Returns index of currently active I2C bus. Zero-based. 259 */ 260 unsigned int i2c_get_bus_num(void) 261 { 262 return gd->cur_i2c_bus; 263 } 264 265 /* 266 * i2c_set_bus_num(): 267 * ------------------ 268 * 269 * Change the active I2C bus. Subsequent read/write calls will 270 * go to this one. Sets all of the muxes in a proper condition 271 * if that bus is behind muxes. 272 * If previously selected bus is behind the muxes turns off all the 273 * muxes along the path to that bus. 274 * 275 * bus - bus index, zero based 276 * 277 * Returns: 0 on success, not 0 on failure 278 */ 279 int i2c_set_bus_num(unsigned int bus) 280 { 281 int max = ll_entry_count(struct i2c_adapter, i2c); 282 283 if (I2C_ADAPTER(bus) >= max) { 284 printf("Error, wrong i2c adapter %d max %d possible\n", 285 I2C_ADAPTER(bus), max); 286 return -2; 287 } 288 #ifndef CONFIG_SYS_I2C_DIRECT_BUS 289 if (bus >= CONFIG_SYS_NUM_I2C_BUSES) 290 return -1; 291 #endif 292 293 if ((bus == I2C_BUS) && (I2C_ADAP->init_done > 0)) 294 return 0; 295 296 #ifndef CONFIG_SYS_I2C_DIRECT_BUS 297 i2c_mux_disconnet_all(); 298 #endif 299 300 gd->cur_i2c_bus = bus; 301 if (I2C_ADAP->init_done == 0) 302 i2c_init_bus(bus, I2C_ADAP->speed, I2C_ADAP->slaveaddr); 303 304 #ifndef CONFIG_SYS_I2C_DIRECT_BUS 305 i2c_mux_set_all(); 306 #endif 307 return 0; 308 } 309 310 /* 311 * Probe the given I2C chip address. Returns 0 if a chip responded, 312 * not 0 on failure. 313 */ 314 int i2c_probe(uint8_t chip) 315 { 316 return I2C_ADAP->probe(I2C_ADAP, chip); 317 } 318 319 /* 320 * Read/Write interface: 321 * chip: I2C chip address, range 0..127 322 * addr: Memory (register) address within the chip 323 * alen: Number of bytes to use for addr (typically 1, 2 for larger 324 * memories, 0 for register type devices with only one 325 * register) 326 * buffer: Where to read/write the data 327 * len: How many bytes to read/write 328 * 329 * Returns: 0 on success, not 0 on failure 330 */ 331 int i2c_read(uint8_t chip, unsigned int addr, int alen, 332 uint8_t *buffer, int len) 333 { 334 return I2C_ADAP->read(I2C_ADAP, chip, addr, alen, buffer, len); 335 } 336 337 int i2c_write(uint8_t chip, unsigned int addr, int alen, 338 uint8_t *buffer, int len) 339 { 340 return I2C_ADAP->write(I2C_ADAP, chip, addr, alen, buffer, len); 341 } 342 343 unsigned int i2c_set_bus_speed(unsigned int speed) 344 { 345 unsigned int ret; 346 347 if (I2C_ADAP->set_bus_speed == NULL) 348 return 0; 349 ret = I2C_ADAP->set_bus_speed(I2C_ADAP, speed); 350 if (gd->flags & GD_FLG_RELOC) 351 I2C_ADAP->speed = ret; 352 353 return ret; 354 } 355 356 unsigned int i2c_get_bus_speed(void) 357 { 358 struct i2c_adapter *cur = I2C_ADAP; 359 return cur->speed; 360 } 361 362 uint8_t i2c_reg_read(uint8_t addr, uint8_t reg) 363 { 364 uint8_t buf; 365 366 #ifdef CONFIG_8xx 367 /* MPC8xx needs this. Maybe one day we can get rid of it. */ 368 /* maybe it is now the time for it ... */ 369 i2c_set_bus_num(i2c_get_bus_num()); 370 #endif 371 i2c_read(addr, reg, 1, &buf, 1); 372 373 #ifdef DEBUG 374 printf("%s: bus=%d addr=0x%02x, reg=0x%02x, val=0x%02x\n", 375 __func__, i2c_get_bus_num(), addr, reg, buf); 376 #endif 377 378 return buf; 379 } 380 381 void i2c_reg_write(uint8_t addr, uint8_t reg, uint8_t val) 382 { 383 #ifdef CONFIG_8xx 384 /* MPC8xx needs this. Maybe one day we can get rid of it. */ 385 /* maybe it is now the time for it ... */ 386 i2c_set_bus_num(i2c_get_bus_num()); 387 #endif 388 389 #ifdef DEBUG 390 printf("%s: bus=%d addr=0x%02x, reg=0x%02x, val=0x%02x\n", 391 __func__, i2c_get_bus_num(), addr, reg, val); 392 #endif 393 394 i2c_write(addr, reg, 1, &val, 1); 395 } 396 397 void __i2c_init(int speed, int slaveaddr) 398 { 399 i2c_init_bus(i2c_get_bus_num(), speed, slaveaddr); 400 } 401 void i2c_init(int speed, int slaveaddr) 402 __attribute__((weak, alias("__i2c_init"))); 403