1 /* 2 * Copyright 2006,2009 Freescale Semiconductor, Inc. 3 * 4 * 2012, Heiko Schocher, DENX Software Engineering, hs@denx.de. 5 * Changes for multibus/multiadapter I2C support. 6 * 7 * SPDX-License-Identifier: GPL-2.0 8 */ 9 10 #include <common.h> 11 #include <command.h> 12 #include <i2c.h> /* Functional interface */ 13 #include <asm/io.h> 14 #include <asm/fsl_i2c.h> /* HW definitions */ 15 #include <dm.h> 16 #include <mapmem.h> 17 18 /* The maximum number of microseconds we will wait until another master has 19 * released the bus. If not defined in the board header file, then use a 20 * generic value. 21 */ 22 #ifndef CONFIG_I2C_MBB_TIMEOUT 23 #define CONFIG_I2C_MBB_TIMEOUT 100000 24 #endif 25 26 /* The maximum number of microseconds we will wait for a read or write 27 * operation to complete. If not defined in the board header file, then use a 28 * generic value. 29 */ 30 #ifndef CONFIG_I2C_TIMEOUT 31 #define CONFIG_I2C_TIMEOUT 100000 32 #endif 33 34 #define I2C_READ_BIT 1 35 #define I2C_WRITE_BIT 0 36 37 DECLARE_GLOBAL_DATA_PTR; 38 39 #ifndef CONFIG_DM_I2C 40 static const struct fsl_i2c_base *i2c_base[4] = { 41 (struct fsl_i2c_base *)(CONFIG_SYS_IMMR + CONFIG_SYS_FSL_I2C_OFFSET), 42 #ifdef CONFIG_SYS_FSL_I2C2_OFFSET 43 (struct fsl_i2c_base *)(CONFIG_SYS_IMMR + CONFIG_SYS_FSL_I2C2_OFFSET), 44 #endif 45 #ifdef CONFIG_SYS_FSL_I2C3_OFFSET 46 (struct fsl_i2c_base *)(CONFIG_SYS_IMMR + CONFIG_SYS_FSL_I2C3_OFFSET), 47 #endif 48 #ifdef CONFIG_SYS_FSL_I2C4_OFFSET 49 (struct fsl_i2c_base *)(CONFIG_SYS_IMMR + CONFIG_SYS_FSL_I2C4_OFFSET) 50 #endif 51 }; 52 #endif 53 54 /* I2C speed map for a DFSR value of 1 */ 55 56 #ifdef __M68K__ 57 /* 58 * Map I2C frequency dividers to FDR and DFSR values 59 * 60 * This structure is used to define the elements of a table that maps I2C 61 * frequency divider (I2C clock rate divided by I2C bus speed) to a value to be 62 * programmed into the Frequency Divider Ratio (FDR) and Digital Filter 63 * Sampling Rate (DFSR) registers. 64 * 65 * The actual table should be defined in the board file, and it must be called 66 * fsl_i2c_speed_map[]. 67 * 68 * The last entry of the table must have a value of {-1, X}, where X is same 69 * FDR/DFSR values as the second-to-last entry. This guarantees that any 70 * search through the array will always find a match. 71 * 72 * The values of the divider must be in increasing numerical order, i.e. 73 * fsl_i2c_speed_map[x+1].divider > fsl_i2c_speed_map[x].divider. 74 * 75 * For this table, the values are based on a value of 1 for the DFSR 76 * register. See the application note AN2919 "Determining the I2C Frequency 77 * Divider Ratio for SCL" 78 * 79 * ColdFire I2C frequency dividers for FDR values are different from 80 * PowerPC. The protocol to use the I2C module is still the same. 81 * A different table is defined and are based on MCF5xxx user manual. 82 * 83 */ 84 static const struct { 85 unsigned short divider; 86 u8 fdr; 87 } fsl_i2c_speed_map[] = { 88 {20, 32}, {22, 33}, {24, 34}, {26, 35}, 89 {28, 0}, {28, 36}, {30, 1}, {32, 37}, 90 {34, 2}, {36, 38}, {40, 3}, {40, 39}, 91 {44, 4}, {48, 5}, {48, 40}, {56, 6}, 92 {56, 41}, {64, 42}, {68, 7}, {72, 43}, 93 {80, 8}, {80, 44}, {88, 9}, {96, 41}, 94 {104, 10}, {112, 42}, {128, 11}, {128, 43}, 95 {144, 12}, {160, 13}, {160, 48}, {192, 14}, 96 {192, 49}, {224, 50}, {240, 15}, {256, 51}, 97 {288, 16}, {320, 17}, {320, 52}, {384, 18}, 98 {384, 53}, {448, 54}, {480, 19}, {512, 55}, 99 {576, 20}, {640, 21}, {640, 56}, {768, 22}, 100 {768, 57}, {960, 23}, {896, 58}, {1024, 59}, 101 {1152, 24}, {1280, 25}, {1280, 60}, {1536, 26}, 102 {1536, 61}, {1792, 62}, {1920, 27}, {2048, 63}, 103 {2304, 28}, {2560, 29}, {3072, 30}, {3840, 31}, 104 {-1, 31} 105 }; 106 #endif 107 108 /** 109 * Set the I2C bus speed for a given I2C device 110 * 111 * @param base: the I2C device registers 112 * @i2c_clk: I2C bus clock frequency 113 * @speed: the desired speed of the bus 114 * 115 * The I2C device must be stopped before calling this function. 116 * 117 * The return value is the actual bus speed that is set. 118 */ 119 static unsigned int set_i2c_bus_speed(const struct fsl_i2c_base *base, 120 unsigned int i2c_clk, unsigned int speed) 121 { 122 unsigned short divider = min(i2c_clk / speed, (unsigned int)USHRT_MAX); 123 124 /* 125 * We want to choose an FDR/DFSR that generates an I2C bus speed that 126 * is equal to or lower than the requested speed. That means that we 127 * want the first divider that is equal to or greater than the 128 * calculated divider. 129 */ 130 #ifdef __PPC__ 131 u8 dfsr, fdr = 0x31; /* Default if no FDR found */ 132 /* a, b and dfsr matches identifiers A,B and C respectively in AN2919 */ 133 unsigned short a, b, ga, gb; 134 unsigned long c_div, est_div; 135 136 #ifdef CONFIG_FSL_I2C_CUSTOM_DFSR 137 dfsr = CONFIG_FSL_I2C_CUSTOM_DFSR; 138 #else 139 /* Condition 1: dfsr <= 50/T */ 140 dfsr = (5 * (i2c_clk / 1000)) / 100000; 141 #endif 142 #ifdef CONFIG_FSL_I2C_CUSTOM_FDR 143 fdr = CONFIG_FSL_I2C_CUSTOM_FDR; 144 speed = i2c_clk / divider; /* Fake something */ 145 #else 146 debug("Requested speed:%d, i2c_clk:%d\n", speed, i2c_clk); 147 if (!dfsr) 148 dfsr = 1; 149 150 est_div = ~0; 151 for (ga = 0x4, a = 10; a <= 30; ga++, a += 2) { 152 for (gb = 0; gb < 8; gb++) { 153 b = 16 << gb; 154 c_div = b * (a + ((3*dfsr)/b)*2); 155 if ((c_div > divider) && (c_div < est_div)) { 156 unsigned short bin_gb, bin_ga; 157 158 est_div = c_div; 159 bin_gb = gb << 2; 160 bin_ga = (ga & 0x3) | ((ga & 0x4) << 3); 161 fdr = bin_gb | bin_ga; 162 speed = i2c_clk / est_div; 163 debug("FDR:0x%.2x, div:%ld, ga:0x%x, gb:0x%x, " 164 "a:%d, b:%d, speed:%d\n", 165 fdr, est_div, ga, gb, a, b, speed); 166 /* Condition 2 not accounted for */ 167 debug("Tr <= %d ns\n", 168 (b - 3 * dfsr) * 1000000 / 169 (i2c_clk / 1000)); 170 } 171 } 172 if (a == 20) 173 a += 2; 174 if (a == 24) 175 a += 4; 176 } 177 debug("divider:%d, est_div:%ld, DFSR:%d\n", divider, est_div, dfsr); 178 debug("FDR:0x%.2x, speed:%d\n", fdr, speed); 179 #endif 180 writeb(dfsr, &base->dfsrr); /* set default filter */ 181 writeb(fdr, &base->fdr); /* set bus speed */ 182 #else 183 unsigned int i; 184 185 for (i = 0; i < ARRAY_SIZE(fsl_i2c_speed_map); i++) 186 if (fsl_i2c_speed_map[i].divider >= divider) { 187 u8 fdr; 188 189 fdr = fsl_i2c_speed_map[i].fdr; 190 speed = i2c_clk / fsl_i2c_speed_map[i].divider; 191 writeb(fdr, &base->fdr); /* set bus speed */ 192 193 break; 194 } 195 #endif 196 return speed; 197 } 198 199 #ifndef CONFIG_DM_I2C 200 static unsigned int get_i2c_clock(int bus) 201 { 202 if (bus) 203 return gd->arch.i2c2_clk; /* I2C2 clock */ 204 else 205 return gd->arch.i2c1_clk; /* I2C1 clock */ 206 } 207 #endif 208 209 static int fsl_i2c_fixup(const struct fsl_i2c_base *base) 210 { 211 const unsigned long long timeout = usec2ticks(CONFIG_I2C_MBB_TIMEOUT); 212 unsigned long long timeval = 0; 213 int ret = -1; 214 unsigned int flags = 0; 215 216 #ifdef CONFIG_SYS_FSL_ERRATUM_I2C_A004447 217 unsigned int svr = get_svr(); 218 if ((SVR_SOC_VER(svr) == SVR_8548 && IS_SVR_REV(svr, 3, 1)) || 219 (SVR_REV(svr) <= CONFIG_SYS_FSL_A004447_SVR_REV)) 220 flags = I2C_CR_BIT6; 221 #endif 222 223 writeb(I2C_CR_MEN | I2C_CR_MSTA, &base->cr); 224 225 timeval = get_ticks(); 226 while (!(readb(&base->sr) & I2C_SR_MBB)) { 227 if ((get_ticks() - timeval) > timeout) 228 goto err; 229 } 230 231 if (readb(&base->sr) & I2C_SR_MAL) { 232 /* SDA is stuck low */ 233 writeb(0, &base->cr); 234 udelay(100); 235 writeb(I2C_CR_MSTA | flags, &base->cr); 236 writeb(I2C_CR_MEN | I2C_CR_MSTA | flags, &base->cr); 237 } 238 239 readb(&base->dr); 240 241 timeval = get_ticks(); 242 while (!(readb(&base->sr) & I2C_SR_MIF)) { 243 if ((get_ticks() - timeval) > timeout) 244 goto err; 245 } 246 ret = 0; 247 248 err: 249 writeb(I2C_CR_MEN | flags, &base->cr); 250 writeb(0, &base->sr); 251 udelay(100); 252 253 return ret; 254 } 255 256 static void __i2c_init(const struct fsl_i2c_base *base, int speed, int 257 slaveadd, int i2c_clk, int busnum) 258 { 259 const unsigned long long timeout = usec2ticks(CONFIG_I2C_MBB_TIMEOUT); 260 unsigned long long timeval; 261 262 #ifdef CONFIG_SYS_I2C_INIT_BOARD 263 /* Call board specific i2c bus reset routine before accessing the 264 * environment, which might be in a chip on that bus. For details 265 * about this problem see doc/I2C_Edge_Conditions. 266 */ 267 i2c_init_board(); 268 #endif 269 writeb(0, &base->cr); /* stop I2C controller */ 270 udelay(5); /* let it shutdown in peace */ 271 set_i2c_bus_speed(base, i2c_clk, speed); 272 writeb(slaveadd << 1, &base->adr);/* write slave address */ 273 writeb(0x0, &base->sr); /* clear status register */ 274 writeb(I2C_CR_MEN, &base->cr); /* start I2C controller */ 275 276 timeval = get_ticks(); 277 while (readb(&base->sr) & I2C_SR_MBB) { 278 if ((get_ticks() - timeval) < timeout) 279 continue; 280 281 if (fsl_i2c_fixup(base)) 282 debug("i2c_init: BUS#%d failed to init\n", 283 busnum); 284 285 break; 286 } 287 288 #ifdef CONFIG_SYS_I2C_BOARD_LATE_INIT 289 /* Call board specific i2c bus reset routine AFTER the bus has been 290 * initialized. Use either this callpoint or i2c_init_board; 291 * which is called before i2c_init operations. 292 * For details about this problem see doc/I2C_Edge_Conditions. 293 */ 294 i2c_board_late_init(); 295 #endif 296 } 297 298 static int 299 i2c_wait4bus(const struct fsl_i2c_base *base) 300 { 301 unsigned long long timeval = get_ticks(); 302 const unsigned long long timeout = usec2ticks(CONFIG_I2C_MBB_TIMEOUT); 303 304 while (readb(&base->sr) & I2C_SR_MBB) { 305 if ((get_ticks() - timeval) > timeout) 306 return -1; 307 } 308 309 return 0; 310 } 311 312 static inline int 313 i2c_wait(const struct fsl_i2c_base *base, int write) 314 { 315 u32 csr; 316 unsigned long long timeval = get_ticks(); 317 const unsigned long long timeout = usec2ticks(CONFIG_I2C_TIMEOUT); 318 319 do { 320 csr = readb(&base->sr); 321 if (!(csr & I2C_SR_MIF)) 322 continue; 323 /* Read again to allow register to stabilise */ 324 csr = readb(&base->sr); 325 326 writeb(0x0, &base->sr); 327 328 if (csr & I2C_SR_MAL) { 329 debug("i2c_wait: MAL\n"); 330 return -1; 331 } 332 333 if (!(csr & I2C_SR_MCF)) { 334 debug("i2c_wait: unfinished\n"); 335 return -1; 336 } 337 338 if (write == I2C_WRITE_BIT && (csr & I2C_SR_RXAK)) { 339 debug("i2c_wait: No RXACK\n"); 340 return -1; 341 } 342 343 return 0; 344 } while ((get_ticks() - timeval) < timeout); 345 346 debug("i2c_wait: timed out\n"); 347 return -1; 348 } 349 350 static inline int 351 i2c_write_addr(const struct fsl_i2c_base *base, u8 dev, u8 dir, int rsta) 352 { 353 writeb(I2C_CR_MEN | I2C_CR_MSTA | I2C_CR_MTX 354 | (rsta ? I2C_CR_RSTA : 0), 355 &base->cr); 356 357 writeb((dev << 1) | dir, &base->dr); 358 359 if (i2c_wait(base, I2C_WRITE_BIT) < 0) 360 return 0; 361 362 return 1; 363 } 364 365 static inline int 366 __i2c_write_data(const struct fsl_i2c_base *base, u8 *data, int length) 367 { 368 int i; 369 370 for (i = 0; i < length; i++) { 371 writeb(data[i], &base->dr); 372 373 if (i2c_wait(base, I2C_WRITE_BIT) < 0) 374 break; 375 } 376 377 return i; 378 } 379 380 static inline int 381 __i2c_read_data(const struct fsl_i2c_base *base, u8 *data, int length) 382 { 383 int i; 384 385 writeb(I2C_CR_MEN | I2C_CR_MSTA | ((length == 1) ? I2C_CR_TXAK : 0), 386 &base->cr); 387 388 /* dummy read */ 389 readb(&base->dr); 390 391 for (i = 0; i < length; i++) { 392 if (i2c_wait(base, I2C_READ_BIT) < 0) 393 break; 394 395 /* Generate ack on last next to last byte */ 396 if (i == length - 2) 397 writeb(I2C_CR_MEN | I2C_CR_MSTA | I2C_CR_TXAK, 398 &base->cr); 399 400 /* Do not generate stop on last byte */ 401 if (i == length - 1) 402 writeb(I2C_CR_MEN | I2C_CR_MSTA | I2C_CR_MTX, 403 &base->cr); 404 405 data[i] = readb(&base->dr); 406 } 407 408 return i; 409 } 410 411 static int 412 __i2c_read(const struct fsl_i2c_base *base, u8 chip_addr, u8 *offset, int olen, 413 u8 *data, int dlen) 414 { 415 int ret = -1; /* signal error */ 416 417 if (i2c_wait4bus(base) < 0) 418 return -1; 419 420 /* Some drivers use offset lengths in excess of 4 bytes. These drivers 421 * adhere to the following convention: 422 * - the offset length is passed as negative (that is, the absolute 423 * value of olen is the actual offset length) 424 * - the offset itself is passed in data, which is overwritten by the 425 * subsequent read operation 426 */ 427 if (olen < 0) { 428 if (i2c_write_addr(base, chip_addr, I2C_WRITE_BIT, 0) != 0) 429 ret = __i2c_write_data(base, data, -olen); 430 431 if (ret != -olen) 432 return -1; 433 434 if (dlen && i2c_write_addr(base, chip_addr, 435 I2C_READ_BIT, 1) != 0) 436 ret = __i2c_read_data(base, data, dlen); 437 } else { 438 if ((!dlen || olen > 0) && 439 i2c_write_addr(base, chip_addr, I2C_WRITE_BIT, 0) != 0 && 440 __i2c_write_data(base, offset, olen) == olen) 441 ret = 0; /* No error so far */ 442 443 if (dlen && i2c_write_addr(base, chip_addr, I2C_READ_BIT, 444 olen ? 1 : 0) != 0) 445 ret = __i2c_read_data(base, data, dlen); 446 } 447 448 writeb(I2C_CR_MEN, &base->cr); 449 450 if (i2c_wait4bus(base)) /* Wait until STOP */ 451 debug("i2c_read: wait4bus timed out\n"); 452 453 if (ret == dlen) 454 return 0; 455 456 return -1; 457 } 458 459 static int 460 __i2c_write(const struct fsl_i2c_base *base, u8 chip_addr, u8 *offset, int olen, 461 u8 *data, int dlen) 462 { 463 int ret = -1; /* signal error */ 464 465 if (i2c_wait4bus(base) < 0) 466 return -1; 467 468 if (i2c_write_addr(base, chip_addr, I2C_WRITE_BIT, 0) != 0 && 469 __i2c_write_data(base, offset, olen) == olen) { 470 ret = __i2c_write_data(base, data, dlen); 471 } 472 473 writeb(I2C_CR_MEN, &base->cr); 474 if (i2c_wait4bus(base)) /* Wait until STOP */ 475 debug("i2c_write: wait4bus timed out\n"); 476 477 if (ret == dlen) 478 return 0; 479 480 return -1; 481 } 482 483 static int 484 __i2c_probe_chip(const struct fsl_i2c_base *base, uchar chip) 485 { 486 /* For unknow reason the controller will ACK when 487 * probing for a slave with the same address, so skip 488 * it. 489 */ 490 if (chip == (readb(&base->adr) >> 1)) 491 return -1; 492 493 return __i2c_read(base, chip, 0, 0, NULL, 0); 494 } 495 496 static unsigned int __i2c_set_bus_speed(const struct fsl_i2c_base *base, 497 unsigned int speed, int i2c_clk) 498 { 499 writeb(0, &base->cr); /* stop controller */ 500 set_i2c_bus_speed(base, i2c_clk, speed); 501 writeb(I2C_CR_MEN, &base->cr); /* start controller */ 502 503 return 0; 504 } 505 506 #ifndef CONFIG_DM_I2C 507 static void fsl_i2c_init(struct i2c_adapter *adap, int speed, int slaveadd) 508 { 509 __i2c_init(i2c_base[adap->hwadapnr], speed, slaveadd, 510 get_i2c_clock(adap->hwadapnr), adap->hwadapnr); 511 } 512 513 static int 514 fsl_i2c_probe_chip(struct i2c_adapter *adap, uchar chip) 515 { 516 return __i2c_probe_chip(i2c_base[adap->hwadapnr], chip); 517 } 518 519 static int 520 fsl_i2c_read(struct i2c_adapter *adap, u8 chip_addr, uint offset, int olen, 521 u8 *data, int dlen) 522 { 523 u8 *o = (u8 *)&offset; 524 return __i2c_read(i2c_base[adap->hwadapnr], chip_addr, &o[4 - olen], 525 olen, data, dlen); 526 } 527 528 static int 529 fsl_i2c_write(struct i2c_adapter *adap, u8 chip_addr, uint offset, int olen, 530 u8 *data, int dlen) 531 { 532 u8 *o = (u8 *)&offset; 533 return __i2c_write(i2c_base[adap->hwadapnr], chip_addr, &o[4 - olen], 534 olen, data, dlen); 535 } 536 537 static unsigned int fsl_i2c_set_bus_speed(struct i2c_adapter *adap, 538 unsigned int speed) 539 { 540 return __i2c_set_bus_speed(i2c_base[adap->hwadapnr], speed, 541 get_i2c_clock(adap->hwadapnr)); 542 } 543 544 /* 545 * Register fsl i2c adapters 546 */ 547 U_BOOT_I2C_ADAP_COMPLETE(fsl_0, fsl_i2c_init, fsl_i2c_probe_chip, fsl_i2c_read, 548 fsl_i2c_write, fsl_i2c_set_bus_speed, 549 CONFIG_SYS_FSL_I2C_SPEED, CONFIG_SYS_FSL_I2C_SLAVE, 550 0) 551 #ifdef CONFIG_SYS_FSL_I2C2_OFFSET 552 U_BOOT_I2C_ADAP_COMPLETE(fsl_1, fsl_i2c_init, fsl_i2c_probe_chip, fsl_i2c_read, 553 fsl_i2c_write, fsl_i2c_set_bus_speed, 554 CONFIG_SYS_FSL_I2C2_SPEED, CONFIG_SYS_FSL_I2C2_SLAVE, 555 1) 556 #endif 557 #ifdef CONFIG_SYS_FSL_I2C3_OFFSET 558 U_BOOT_I2C_ADAP_COMPLETE(fsl_2, fsl_i2c_init, fsl_i2c_probe_chip, fsl_i2c_read, 559 fsl_i2c_write, fsl_i2c_set_bus_speed, 560 CONFIG_SYS_FSL_I2C3_SPEED, CONFIG_SYS_FSL_I2C3_SLAVE, 561 2) 562 #endif 563 #ifdef CONFIG_SYS_FSL_I2C4_OFFSET 564 U_BOOT_I2C_ADAP_COMPLETE(fsl_3, fsl_i2c_init, fsl_i2c_probe_chip, fsl_i2c_read, 565 fsl_i2c_write, fsl_i2c_set_bus_speed, 566 CONFIG_SYS_FSL_I2C4_SPEED, CONFIG_SYS_FSL_I2C4_SLAVE, 567 3) 568 #endif 569 #else /* CONFIG_DM_I2C */ 570 static int fsl_i2c_probe_chip(struct udevice *bus, u32 chip_addr, 571 u32 chip_flags) 572 { 573 struct fsl_i2c_dev *dev = dev_get_priv(bus); 574 return __i2c_probe_chip(dev->base, chip_addr); 575 } 576 577 static int fsl_i2c_set_bus_speed(struct udevice *bus, unsigned int speed) 578 { 579 struct fsl_i2c_dev *dev = dev_get_priv(bus); 580 return __i2c_set_bus_speed(dev->base, speed, dev->i2c_clk); 581 } 582 583 static int fsl_i2c_ofdata_to_platdata(struct udevice *bus) 584 { 585 struct fsl_i2c_dev *dev = dev_get_priv(bus); 586 fdt_addr_t addr; 587 fdt_size_t size; 588 int node = dev_of_offset(bus); 589 590 addr = fdtdec_get_addr_size_auto_noparent(gd->fdt_blob, node, "reg", 0, 591 &size, false); 592 593 dev->base = map_sysmem(CONFIG_SYS_IMMR + addr, size); 594 595 if (!dev->base) 596 return -ENOMEM; 597 598 dev->index = fdtdec_get_int(gd->fdt_blob, node, "cell-index", -1); 599 dev->slaveadd = fdtdec_get_int(gd->fdt_blob, node, 600 "u-boot,i2c-slave-addr", 0x7f); 601 dev->speed = fdtdec_get_int(gd->fdt_blob, node, "clock-frequency", 602 400000); 603 604 dev->i2c_clk = dev->index ? gd->arch.i2c2_clk : gd->arch.i2c1_clk; 605 606 return 0; 607 } 608 609 static int fsl_i2c_probe(struct udevice *bus) 610 { 611 struct fsl_i2c_dev *dev = dev_get_priv(bus); 612 __i2c_init(dev->base, dev->speed, dev->slaveadd, dev->i2c_clk, 613 dev->index); 614 return 0; 615 } 616 617 static int fsl_i2c_xfer(struct udevice *bus, struct i2c_msg *msg, int nmsgs) 618 { 619 struct fsl_i2c_dev *dev = dev_get_priv(bus); 620 struct i2c_msg *dmsg, *omsg, dummy; 621 622 memset(&dummy, 0, sizeof(struct i2c_msg)); 623 624 /* We expect either two messages (one with an offset and one with the 625 * actucal data) or one message (just data) */ 626 if (nmsgs > 2 || nmsgs == 0) { 627 debug("%s: Only one or two messages are supported.", __func__); 628 return -1; 629 } 630 631 omsg = nmsgs == 1 ? &dummy : msg; 632 dmsg = nmsgs == 1 ? msg : msg + 1; 633 634 if (dmsg->flags & I2C_M_RD) 635 return __i2c_read(dev->base, dmsg->addr, omsg->buf, omsg->len, 636 dmsg->buf, dmsg->len); 637 else 638 return __i2c_write(dev->base, dmsg->addr, omsg->buf, omsg->len, 639 dmsg->buf, dmsg->len); 640 } 641 642 static const struct dm_i2c_ops fsl_i2c_ops = { 643 .xfer = fsl_i2c_xfer, 644 .probe_chip = fsl_i2c_probe_chip, 645 .set_bus_speed = fsl_i2c_set_bus_speed, 646 }; 647 648 static const struct udevice_id fsl_i2c_ids[] = { 649 { .compatible = "fsl-i2c", }, 650 { /* sentinel */ } 651 }; 652 653 U_BOOT_DRIVER(i2c_fsl) = { 654 .name = "i2c_fsl", 655 .id = UCLASS_I2C, 656 .of_match = fsl_i2c_ids, 657 .probe = fsl_i2c_probe, 658 .ofdata_to_platdata = fsl_i2c_ofdata_to_platdata, 659 .priv_auto_alloc_size = sizeof(struct fsl_i2c_dev), 660 .ops = &fsl_i2c_ops, 661 }; 662 663 #endif /* CONFIG_DM_I2C */ 664