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_disconnect_all(void) 178 { 179 struct i2c_bus_hose *i2c_bus_tmp = &i2c_bus[I2C_BUS]; 180 int i; 181 uint8_t buf = 0; 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 disconnect 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 __weak void i2c_init_board(void) 233 { 234 } 235 236 /* 237 * i2c_init_all(): 238 * 239 * not longer needed, will deleted. Actual init the SPD_BUS 240 * for compatibility. 241 * i2c_adap[] must be initialized beforehead with function pointers and 242 * data, including speed and slaveaddr. 243 */ 244 void i2c_init_all(void) 245 { 246 i2c_init_board(); 247 i2c_set_bus_num(CONFIG_SYS_SPD_BUS_NUM); 248 return; 249 } 250 251 /* 252 * i2c_get_bus_num(): 253 * ------------------ 254 * 255 * Returns index of currently active I2C bus. Zero-based. 256 */ 257 unsigned int i2c_get_bus_num(void) 258 { 259 return gd->cur_i2c_bus; 260 } 261 262 /* 263 * i2c_set_bus_num(): 264 * ------------------ 265 * 266 * Change the active I2C bus. Subsequent read/write calls will 267 * go to this one. Sets all of the muxes in a proper condition 268 * if that bus is behind muxes. 269 * If previously selected bus is behind the muxes turns off all the 270 * muxes along the path to that bus. 271 * 272 * bus - bus index, zero based 273 * 274 * Returns: 0 on success, not 0 on failure 275 */ 276 int i2c_set_bus_num(unsigned int bus) 277 { 278 int max; 279 280 if ((bus == I2C_BUS) && (I2C_ADAP->init_done > 0)) 281 return 0; 282 283 #ifndef CONFIG_SYS_I2C_DIRECT_BUS 284 if (bus >= CONFIG_SYS_NUM_I2C_BUSES) 285 return -1; 286 #endif 287 288 max = ll_entry_count(struct i2c_adapter, i2c); 289 if (I2C_ADAPTER(bus) >= max) { 290 printf("Error, wrong i2c adapter %d max %d possible\n", 291 I2C_ADAPTER(bus), max); 292 return -2; 293 } 294 295 #ifndef CONFIG_SYS_I2C_DIRECT_BUS 296 i2c_mux_disconnect_all(); 297 #endif 298 299 gd->cur_i2c_bus = bus; 300 if (I2C_ADAP->init_done == 0) 301 i2c_init_bus(bus, I2C_ADAP->speed, I2C_ADAP->slaveaddr); 302 303 #ifndef CONFIG_SYS_I2C_DIRECT_BUS 304 i2c_mux_set_all(); 305 #endif 306 return 0; 307 } 308 309 /* 310 * Probe the given I2C chip address. Returns 0 if a chip responded, 311 * not 0 on failure. 312 */ 313 int i2c_probe(uint8_t chip) 314 { 315 return I2C_ADAP->probe(I2C_ADAP, chip); 316 } 317 318 /* 319 * Read/Write interface: 320 * chip: I2C chip address, range 0..127 321 * addr: Memory (register) address within the chip 322 * alen: Number of bytes to use for addr (typically 1, 2 for larger 323 * memories, 0 for register type devices with only one 324 * register) 325 * buffer: Where to read/write the data 326 * len: How many bytes to read/write 327 * 328 * Returns: 0 on success, not 0 on failure 329 */ 330 int i2c_read(uint8_t chip, unsigned int addr, int alen, 331 uint8_t *buffer, int len) 332 { 333 return I2C_ADAP->read(I2C_ADAP, chip, addr, alen, buffer, len); 334 } 335 336 int i2c_write(uint8_t chip, unsigned int addr, int alen, 337 uint8_t *buffer, int len) 338 { 339 return I2C_ADAP->write(I2C_ADAP, chip, addr, alen, buffer, len); 340 } 341 342 unsigned int i2c_set_bus_speed(unsigned int speed) 343 { 344 unsigned int ret; 345 346 if (I2C_ADAP->set_bus_speed == NULL) 347 return 0; 348 ret = I2C_ADAP->set_bus_speed(I2C_ADAP, speed); 349 if (gd->flags & GD_FLG_RELOC) 350 I2C_ADAP->speed = (ret == 0) ? speed : 0; 351 352 return ret; 353 } 354 355 unsigned int i2c_get_bus_speed(void) 356 { 357 struct i2c_adapter *cur = I2C_ADAP; 358 return cur->speed; 359 } 360 361 uint8_t i2c_reg_read(uint8_t addr, uint8_t reg) 362 { 363 uint8_t buf; 364 365 #ifdef CONFIG_8xx 366 /* MPC8xx needs this. Maybe one day we can get rid of it. */ 367 /* maybe it is now the time for it ... */ 368 i2c_set_bus_num(i2c_get_bus_num()); 369 #endif 370 i2c_read(addr, reg, 1, &buf, 1); 371 372 #ifdef DEBUG 373 printf("%s: bus=%d addr=0x%02x, reg=0x%02x, val=0x%02x\n", 374 __func__, i2c_get_bus_num(), addr, reg, buf); 375 #endif 376 377 return buf; 378 } 379 380 void i2c_reg_write(uint8_t addr, uint8_t reg, uint8_t val) 381 { 382 #ifdef CONFIG_8xx 383 /* MPC8xx needs this. Maybe one day we can get rid of it. */ 384 /* maybe it is now the time for it ... */ 385 i2c_set_bus_num(i2c_get_bus_num()); 386 #endif 387 388 #ifdef DEBUG 389 printf("%s: bus=%d addr=0x%02x, reg=0x%02x, val=0x%02x\n", 390 __func__, i2c_get_bus_num(), addr, reg, val); 391 #endif 392 393 i2c_write(addr, reg, 1, &val, 1); 394 } 395 396 __weak void i2c_init(int speed, int slaveaddr) 397 { 398 i2c_init_bus(i2c_get_bus_num(), speed, slaveaddr); 399 } 400