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