1 /* 2 * Copyright (C) 2009 Sergey Kubushyn <ksi@koi8.net> 3 * Copyright (C) 2009 - 2013 Heiko Schocher <hs@denx.de> 4 * Changes for multibus/multiadapter I2C support. 5 * 6 * (C) Copyright 2001 7 * Gerald Van Baren, Custom IDEAS, vanbaren@cideas.com. 8 * 9 * SPDX-License-Identifier: GPL-2.0+ 10 * 11 * The original I2C interface was 12 * (C) 2000 by Paolo Scaffardi (arsenio@tin.it) 13 * AIRVENT SAM s.p.a - RIMINI(ITALY) 14 * but has been changed substantially. 15 */ 16 17 #ifndef _I2C_H_ 18 #define _I2C_H_ 19 20 /* 21 * For now there are essentially two parts to this file - driver model 22 * here at the top, and the older code below (with CONFIG_SYS_I2C being 23 * most recent). The plan is to migrate everything to driver model. 24 * The driver model structures and API are separate as they are different 25 * enough as to be incompatible for compilation purposes. 26 */ 27 28 #ifdef CONFIG_DM_I2C 29 30 enum dm_i2c_chip_flags { 31 DM_I2C_CHIP_10BIT = 1 << 0, /* Use 10-bit addressing */ 32 DM_I2C_CHIP_RD_ADDRESS = 1 << 1, /* Send address for each read byte */ 33 DM_I2C_CHIP_WR_ADDRESS = 1 << 2, /* Send address for each write byte */ 34 }; 35 36 /** 37 * struct dm_i2c_chip - information about an i2c chip 38 * 39 * An I2C chip is a device on the I2C bus. It sits at a particular address 40 * and normally supports 7-bit or 10-bit addressing. 41 * 42 * To obtain this structure, use dev_get_parent_platdata(dev) where dev is 43 * the chip to examine. 44 * 45 * @chip_addr: Chip address on bus 46 * @offset_len: Length of offset in bytes. A single byte offset can 47 * represent up to 256 bytes. A value larger than 1 may be 48 * needed for larger devices. 49 * @flags: Flags for this chip (dm_i2c_chip_flags) 50 * @emul: Emulator for this chip address (only used for emulation) 51 */ 52 struct dm_i2c_chip { 53 uint chip_addr; 54 uint offset_len; 55 uint flags; 56 #ifdef CONFIG_SANDBOX 57 struct udevice *emul; 58 #endif 59 }; 60 61 /** 62 * struct dm_i2c_bus- information about an i2c bus 63 * 64 * An I2C bus contains 0 or more chips on it, each at its own address. The 65 * bus can operate at different speeds (measured in Hz, typically 100KHz 66 * or 400KHz). 67 * 68 * To obtain this structure, use bus->uclass_priv where bus is the I2C 69 * bus udevice. 70 * 71 * @speed_hz: Bus speed in hertz (typically 100000) 72 */ 73 struct dm_i2c_bus { 74 int speed_hz; 75 }; 76 77 /** 78 * dm_i2c_read() - read bytes from an I2C chip 79 * 80 * To obtain an I2C device (called a 'chip') given the I2C bus address you 81 * can use i2c_get_chip(). To obtain a bus by bus number use 82 * uclass_get_device_by_seq(UCLASS_I2C, <bus number>). 83 * 84 * To set the address length of a devce use i2c_set_addr_len(). It 85 * defaults to 1. 86 * 87 * @dev: Chip to read from 88 * @offset: Offset within chip to start reading 89 * @buffer: Place to put data 90 * @len: Number of bytes to read 91 * 92 * @return 0 on success, -ve on failure 93 */ 94 int dm_i2c_read(struct udevice *dev, uint offset, uint8_t *buffer, int len); 95 96 /** 97 * dm_i2c_write() - write bytes to an I2C chip 98 * 99 * See notes for dm_i2c_read() above. 100 * 101 * @dev: Chip to write to 102 * @offset: Offset within chip to start writing 103 * @buffer: Buffer containing data to write 104 * @len: Number of bytes to write 105 * 106 * @return 0 on success, -ve on failure 107 */ 108 int dm_i2c_write(struct udevice *dev, uint offset, const uint8_t *buffer, 109 int len); 110 111 /** 112 * dm_i2c_probe() - probe a particular chip address 113 * 114 * This can be useful to check for the existence of a chip on the bus. 115 * It is typically implemented by writing the chip address to the bus 116 * and checking that the chip replies with an ACK. 117 * 118 * @bus: Bus to probe 119 * @chip_addr: 7-bit address to probe (10-bit and others are not supported) 120 * @chip_flags: Flags for the probe (see enum dm_i2c_chip_flags) 121 * @devp: Returns the device found, or NULL if none 122 * @return 0 if a chip was found at that address, -ve if not 123 */ 124 int dm_i2c_probe(struct udevice *bus, uint chip_addr, uint chip_flags, 125 struct udevice **devp); 126 127 /** 128 * i2c_set_bus_speed() - set the speed of a bus 129 * 130 * @bus: Bus to adjust 131 * @speed: Requested speed in Hz 132 * @return 0 if OK, -EINVAL for invalid values 133 */ 134 int i2c_set_bus_speed(struct udevice *bus, unsigned int speed); 135 136 /** 137 * i2c_get_bus_speed() - get the speed of a bus 138 * 139 * @bus: Bus to check 140 * @return speed of selected I2C bus in Hz, -ve on error 141 */ 142 int i2c_get_bus_speed(struct udevice *bus); 143 144 /** 145 * i2c_set_chip_flags() - set flags for a chip 146 * 147 * Typically addresses are 7 bits, but for 10-bit addresses you should set 148 * flags to DM_I2C_CHIP_10BIT. All accesses will then use 10-bit addressing. 149 * 150 * @dev: Chip to adjust 151 * @flags: New flags 152 * @return 0 if OK, -EINVAL if value is unsupported, other -ve value on error 153 */ 154 int i2c_set_chip_flags(struct udevice *dev, uint flags); 155 156 /** 157 * i2c_get_chip_flags() - get flags for a chip 158 * 159 * @dev: Chip to check 160 * @flagsp: Place to put flags 161 * @return 0 if OK, other -ve value on error 162 */ 163 int i2c_get_chip_flags(struct udevice *dev, uint *flagsp); 164 165 /** 166 * i2c_set_offset_len() - set the offset length for a chip 167 * 168 * The offset used to access a chip may be up to 4 bytes long. Typically it 169 * is only 1 byte, which is enough for chips with 256 bytes of memory or 170 * registers. The default value is 1, but you can call this function to 171 * change it. 172 * 173 * @offset_len: New offset length value (typically 1 or 2) 174 */ 175 176 int i2c_set_chip_offset_len(struct udevice *dev, uint offset_len); 177 /** 178 * i2c_deblock() - recover a bus that is in an unknown state 179 * 180 * See the deblock() method in 'struct dm_i2c_ops' for full information 181 * 182 * @bus: Bus to recover 183 * @return 0 if OK, -ve on error 184 */ 185 int i2c_deblock(struct udevice *bus); 186 187 #ifdef CONFIG_DM_I2C_COMPAT 188 /** 189 * i2c_probe() - Compatibility function for driver model 190 * 191 * Calls dm_i2c_probe() on the current bus 192 */ 193 int i2c_probe(uint8_t chip_addr); 194 195 /** 196 * i2c_read() - Compatibility function for driver model 197 * 198 * Calls dm_i2c_read() with the device corresponding to @chip_addr, and offset 199 * set to @addr. @alen must match the current setting for the device. 200 */ 201 int i2c_read(uint8_t chip_addr, unsigned int addr, int alen, uint8_t *buffer, 202 int len); 203 204 /** 205 * i2c_write() - Compatibility function for driver model 206 * 207 * Calls dm_i2c_write() with the device corresponding to @chip_addr, and offset 208 * set to @addr. @alen must match the current setting for the device. 209 */ 210 int i2c_write(uint8_t chip_addr, unsigned int addr, int alen, uint8_t *buffer, 211 int len); 212 213 /** 214 * i2c_get_bus_num_fdt() - Compatibility function for driver model 215 * 216 * @return the bus number associated with the given device tree node 217 */ 218 int i2c_get_bus_num_fdt(int node); 219 220 /** 221 * i2c_get_bus_num() - Compatibility function for driver model 222 * 223 * @return the 'current' bus number 224 */ 225 unsigned int i2c_get_bus_num(void); 226 227 /** 228 * i2c_set_bus_num() - Compatibility function for driver model 229 * 230 * Sets the 'current' bus 231 */ 232 int i2c_set_bus_num(unsigned int bus); 233 234 static inline void I2C_SET_BUS(unsigned int bus) 235 { 236 i2c_set_bus_num(bus); 237 } 238 239 static inline unsigned int I2C_GET_BUS(void) 240 { 241 return i2c_get_bus_num(); 242 } 243 244 /** 245 * i2c_init() - Compatibility function for driver model 246 * 247 * This function does nothing. 248 */ 249 void i2c_init(int speed, int slaveaddr); 250 251 /** 252 * board_i2c_init() - Compatibility function for driver model 253 * 254 * @param blob Device tree blbo 255 * @return the number of I2C bus 256 */ 257 void board_i2c_init(const void *blob); 258 259 #endif 260 261 /* 262 * Not all of these flags are implemented in the U-Boot API 263 */ 264 enum dm_i2c_msg_flags { 265 I2C_M_TEN = 0x0010, /* ten-bit chip address */ 266 I2C_M_RD = 0x0001, /* read data, from slave to master */ 267 I2C_M_STOP = 0x8000, /* send stop after this message */ 268 I2C_M_NOSTART = 0x4000, /* no start before this message */ 269 I2C_M_REV_DIR_ADDR = 0x2000, /* invert polarity of R/W bit */ 270 I2C_M_IGNORE_NAK = 0x1000, /* continue after NAK */ 271 I2C_M_NO_RD_ACK = 0x0800, /* skip the Ack bit on reads */ 272 I2C_M_RECV_LEN = 0x0400, /* length is first received byte */ 273 }; 274 275 /** 276 * struct i2c_msg - an I2C message 277 * 278 * @addr: Slave address 279 * @flags: Flags (see enum dm_i2c_msg_flags) 280 * @len: Length of buffer in bytes, may be 0 for a probe 281 * @buf: Buffer to send/receive, or NULL if no data 282 */ 283 struct i2c_msg { 284 uint addr; 285 uint flags; 286 uint len; 287 u8 *buf; 288 }; 289 290 /** 291 * struct i2c_msg_list - a list of I2C messages 292 * 293 * This is called i2c_rdwr_ioctl_data in Linux but the name does not seem 294 * appropriate in U-Boot. 295 * 296 * @msg: Pointer to i2c_msg array 297 * @nmsgs: Number of elements in the array 298 */ 299 struct i2c_msg_list { 300 struct i2c_msg *msgs; 301 uint nmsgs; 302 }; 303 304 /** 305 * struct dm_i2c_ops - driver operations for I2C uclass 306 * 307 * Drivers should support these operations unless otherwise noted. These 308 * operations are intended to be used by uclass code, not directly from 309 * other code. 310 */ 311 struct dm_i2c_ops { 312 /** 313 * xfer() - transfer a list of I2C messages 314 * 315 * @bus: Bus to read from 316 * @msg: List of messages to transfer 317 * @nmsgs: Number of messages in the list 318 * @return 0 if OK, -EREMOTEIO if the slave did not ACK a byte, 319 * -ECOMM if the speed cannot be supported, -EPROTO if the chip 320 * flags cannot be supported, other -ve value on some other error 321 */ 322 int (*xfer)(struct udevice *bus, struct i2c_msg *msg, int nmsgs); 323 324 /** 325 * probe_chip() - probe for the presense of a chip address 326 * 327 * This function is optional. If omitted, the uclass will send a zero 328 * length message instead. 329 * 330 * @bus: Bus to probe 331 * @chip_addr: Chip address to probe 332 * @chip_flags: Probe flags (enum dm_i2c_chip_flags) 333 * @return 0 if chip was found, -EREMOTEIO if not, -ENOSYS to fall back 334 * to default probem other -ve value on error 335 */ 336 int (*probe_chip)(struct udevice *bus, uint chip_addr, uint chip_flags); 337 338 /** 339 * set_bus_speed() - set the speed of a bus (optional) 340 * 341 * The bus speed value will be updated by the uclass if this function 342 * does not return an error. This method is optional - if it is not 343 * provided then the driver can read the speed from 344 * bus->uclass_priv->speed_hz 345 * 346 * @bus: Bus to adjust 347 * @speed: Requested speed in Hz 348 * @return 0 if OK, -EINVAL for invalid values 349 */ 350 int (*set_bus_speed)(struct udevice *bus, unsigned int speed); 351 352 /** 353 * get_bus_speed() - get the speed of a bus (optional) 354 * 355 * Normally this can be provided by the uclass, but if you want your 356 * driver to check the bus speed by looking at the hardware, you can 357 * implement that here. This method is optional. This method would 358 * normally be expected to return bus->uclass_priv->speed_hz. 359 * 360 * @bus: Bus to check 361 * @return speed of selected I2C bus in Hz, -ve on error 362 */ 363 int (*get_bus_speed)(struct udevice *bus); 364 365 /** 366 * set_flags() - set the flags for a chip (optional) 367 * 368 * This is generally implemented by the uclass, but drivers can 369 * check the value to ensure that unsupported options are not used. 370 * This method is optional. If provided, this method will always be 371 * called when the flags change. 372 * 373 * @dev: Chip to adjust 374 * @flags: New flags value 375 * @return 0 if OK, -EINVAL if value is unsupported 376 */ 377 int (*set_flags)(struct udevice *dev, uint flags); 378 379 /** 380 * deblock() - recover a bus that is in an unknown state 381 * 382 * I2C is a synchronous protocol and resets of the processor in the 383 * middle of an access can block the I2C Bus until a powerdown of 384 * the full unit is done. This is because slaves can be stuck 385 * waiting for addition bus transitions for a transaction that will 386 * never complete. Resetting the I2C master does not help. The only 387 * way is to force the bus through a series of transitions to make 388 * sure that all slaves are done with the transaction. This method 389 * performs this 'deblocking' if support by the driver. 390 * 391 * This method is optional. 392 */ 393 int (*deblock)(struct udevice *bus); 394 }; 395 396 #define i2c_get_ops(dev) ((struct dm_i2c_ops *)(dev)->driver->ops) 397 398 /** 399 * i2c_get_chip() - get a device to use to access a chip on a bus 400 * 401 * This returns the device for the given chip address. The device can then 402 * be used with calls to i2c_read(), i2c_write(), i2c_probe(), etc. 403 * 404 * @bus: Bus to examine 405 * @chip_addr: Chip address for the new device 406 * @offset_len: Length of a register offset in bytes (normally 1) 407 * @devp: Returns pointer to new device if found or -ENODEV if not 408 * found 409 */ 410 int i2c_get_chip(struct udevice *bus, uint chip_addr, uint offset_len, 411 struct udevice **devp); 412 413 /** 414 * i2c_get_chip() - get a device to use to access a chip on a bus number 415 * 416 * This returns the device for the given chip address on a particular bus 417 * number. 418 * 419 * @busnum: Bus number to examine 420 * @chip_addr: Chip address for the new device 421 * @offset_len: Length of a register offset in bytes (normally 1) 422 * @devp: Returns pointer to new device if found or -ENODEV if not 423 * found 424 */ 425 int i2c_get_chip_for_busnum(int busnum, int chip_addr, uint offset_len, 426 struct udevice **devp); 427 428 /** 429 * i2c_chip_ofdata_to_platdata() - Decode standard I2C platform data 430 * 431 * This decodes the chip address from a device tree node and puts it into 432 * its dm_i2c_chip structure. This should be called in your driver's 433 * ofdata_to_platdata() method. 434 * 435 * @blob: Device tree blob 436 * @node: Node offset to read from 437 * @spi: Place to put the decoded information 438 */ 439 int i2c_chip_ofdata_to_platdata(const void *blob, int node, 440 struct dm_i2c_chip *chip); 441 442 #endif 443 444 #ifndef CONFIG_DM_I2C 445 446 /* 447 * WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING 448 * 449 * The implementation MUST NOT use static or global variables if the 450 * I2C routines are used to read SDRAM configuration information 451 * because this is done before the memories are initialized. Limited 452 * use of stack-based variables are OK (the initial stack size is 453 * limited). 454 * 455 * WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING 456 */ 457 458 /* 459 * Configuration items. 460 */ 461 #define I2C_RXTX_LEN 128 /* maximum tx/rx buffer length */ 462 463 #if !defined(CONFIG_SYS_I2C_MAX_HOPS) 464 /* no muxes used bus = i2c adapters */ 465 #define CONFIG_SYS_I2C_DIRECT_BUS 1 466 #define CONFIG_SYS_I2C_MAX_HOPS 0 467 #define CONFIG_SYS_NUM_I2C_BUSES ll_entry_count(struct i2c_adapter, i2c) 468 #else 469 /* we use i2c muxes */ 470 #undef CONFIG_SYS_I2C_DIRECT_BUS 471 #endif 472 473 /* define the I2C bus number for RTC and DTT if not already done */ 474 #if !defined(CONFIG_SYS_RTC_BUS_NUM) 475 #define CONFIG_SYS_RTC_BUS_NUM 0 476 #endif 477 #if !defined(CONFIG_SYS_DTT_BUS_NUM) 478 #define CONFIG_SYS_DTT_BUS_NUM 0 479 #endif 480 #if !defined(CONFIG_SYS_SPD_BUS_NUM) 481 #define CONFIG_SYS_SPD_BUS_NUM 0 482 #endif 483 484 struct i2c_adapter { 485 void (*init)(struct i2c_adapter *adap, int speed, 486 int slaveaddr); 487 int (*probe)(struct i2c_adapter *adap, uint8_t chip); 488 int (*read)(struct i2c_adapter *adap, uint8_t chip, 489 uint addr, int alen, uint8_t *buffer, 490 int len); 491 int (*write)(struct i2c_adapter *adap, uint8_t chip, 492 uint addr, int alen, uint8_t *buffer, 493 int len); 494 uint (*set_bus_speed)(struct i2c_adapter *adap, 495 uint speed); 496 int speed; 497 int waitdelay; 498 int slaveaddr; 499 int init_done; 500 int hwadapnr; 501 char *name; 502 }; 503 504 #define U_BOOT_I2C_MKENT_COMPLETE(_init, _probe, _read, _write, \ 505 _set_speed, _speed, _slaveaddr, _hwadapnr, _name) \ 506 { \ 507 .init = _init, \ 508 .probe = _probe, \ 509 .read = _read, \ 510 .write = _write, \ 511 .set_bus_speed = _set_speed, \ 512 .speed = _speed, \ 513 .slaveaddr = _slaveaddr, \ 514 .init_done = 0, \ 515 .hwadapnr = _hwadapnr, \ 516 .name = #_name \ 517 }; 518 519 #define U_BOOT_I2C_ADAP_COMPLETE(_name, _init, _probe, _read, _write, \ 520 _set_speed, _speed, _slaveaddr, _hwadapnr) \ 521 ll_entry_declare(struct i2c_adapter, _name, i2c) = \ 522 U_BOOT_I2C_MKENT_COMPLETE(_init, _probe, _read, _write, \ 523 _set_speed, _speed, _slaveaddr, _hwadapnr, _name); 524 525 struct i2c_adapter *i2c_get_adapter(int index); 526 527 #ifndef CONFIG_SYS_I2C_DIRECT_BUS 528 struct i2c_mux { 529 int id; 530 char name[16]; 531 }; 532 533 struct i2c_next_hop { 534 struct i2c_mux mux; 535 uint8_t chip; 536 uint8_t channel; 537 }; 538 539 struct i2c_bus_hose { 540 int adapter; 541 struct i2c_next_hop next_hop[CONFIG_SYS_I2C_MAX_HOPS]; 542 }; 543 #define I2C_NULL_HOP {{-1, ""}, 0, 0} 544 extern struct i2c_bus_hose i2c_bus[]; 545 546 #define I2C_ADAPTER(bus) i2c_bus[bus].adapter 547 #else 548 #define I2C_ADAPTER(bus) bus 549 #endif 550 #define I2C_BUS gd->cur_i2c_bus 551 552 #define I2C_ADAP_NR(bus) i2c_get_adapter(I2C_ADAPTER(bus)) 553 #define I2C_ADAP I2C_ADAP_NR(gd->cur_i2c_bus) 554 #define I2C_ADAP_HWNR (I2C_ADAP->hwadapnr) 555 556 #ifndef CONFIG_SYS_I2C_DIRECT_BUS 557 #define I2C_MUX_PCA9540_ID 1 558 #define I2C_MUX_PCA9540 {I2C_MUX_PCA9540_ID, "PCA9540B"} 559 #define I2C_MUX_PCA9542_ID 2 560 #define I2C_MUX_PCA9542 {I2C_MUX_PCA9542_ID, "PCA9542A"} 561 #define I2C_MUX_PCA9544_ID 3 562 #define I2C_MUX_PCA9544 {I2C_MUX_PCA9544_ID, "PCA9544A"} 563 #define I2C_MUX_PCA9547_ID 4 564 #define I2C_MUX_PCA9547 {I2C_MUX_PCA9547_ID, "PCA9547A"} 565 #define I2C_MUX_PCA9548_ID 5 566 #define I2C_MUX_PCA9548 {I2C_MUX_PCA9548_ID, "PCA9548"} 567 #endif 568 569 #ifndef I2C_SOFT_DECLARATIONS 570 # if defined(CONFIG_MPC8260) 571 # define I2C_SOFT_DECLARATIONS volatile ioport_t *iop = ioport_addr((immap_t *)CONFIG_SYS_IMMR, I2C_PORT); 572 # elif defined(CONFIG_8xx) 573 # define I2C_SOFT_DECLARATIONS volatile immap_t *immr = (immap_t *)CONFIG_SYS_IMMR; 574 575 # elif (defined(CONFIG_AT91RM9200) || \ 576 defined(CONFIG_AT91SAM9260) || defined(CONFIG_AT91SAM9261) || \ 577 defined(CONFIG_AT91SAM9263)) 578 # define I2C_SOFT_DECLARATIONS at91_pio_t *pio = (at91_pio_t *) ATMEL_BASE_PIOA; 579 # else 580 # define I2C_SOFT_DECLARATIONS 581 # endif 582 #endif 583 584 #ifdef CONFIG_8xx 585 /* Set default value for the I2C bus speed on 8xx. In the 586 * future, we'll define these in all 8xx board config files. 587 */ 588 #ifndef CONFIG_SYS_I2C_SPEED 589 #define CONFIG_SYS_I2C_SPEED 50000 590 #endif 591 #endif 592 593 /* 594 * Many boards/controllers/drivers don't support an I2C slave interface so 595 * provide a default slave address for them for use in common code. A real 596 * value for CONFIG_SYS_I2C_SLAVE should be defined for any board which does 597 * support a slave interface. 598 */ 599 #ifndef CONFIG_SYS_I2C_SLAVE 600 #define CONFIG_SYS_I2C_SLAVE 0xfe 601 #endif 602 603 /* 604 * Initialization, must be called once on start up, may be called 605 * repeatedly to change the speed and slave addresses. 606 */ 607 void i2c_init(int speed, int slaveaddr); 608 void i2c_init_board(void); 609 #ifdef CONFIG_SYS_I2C_BOARD_LATE_INIT 610 void i2c_board_late_init(void); 611 #endif 612 613 #ifdef CONFIG_SYS_I2C 614 /* 615 * i2c_get_bus_num: 616 * 617 * Returns index of currently active I2C bus. Zero-based. 618 */ 619 unsigned int i2c_get_bus_num(void); 620 621 /* 622 * i2c_set_bus_num: 623 * 624 * Change the active I2C bus. Subsequent read/write calls will 625 * go to this one. 626 * 627 * bus - bus index, zero based 628 * 629 * Returns: 0 on success, not 0 on failure 630 * 631 */ 632 int i2c_set_bus_num(unsigned int bus); 633 634 /* 635 * i2c_init_all(): 636 * 637 * Initializes all I2C adapters in the system. All i2c_adap structures must 638 * be initialized beforehead with function pointers and data, including 639 * speed and slaveaddr. Returns 0 on success, non-0 on failure. 640 */ 641 void i2c_init_all(void); 642 643 /* 644 * Probe the given I2C chip address. Returns 0 if a chip responded, 645 * not 0 on failure. 646 */ 647 int i2c_probe(uint8_t chip); 648 649 /* 650 * Read/Write interface: 651 * chip: I2C chip address, range 0..127 652 * addr: Memory (register) address within the chip 653 * alen: Number of bytes to use for addr (typically 1, 2 for larger 654 * memories, 0 for register type devices with only one 655 * register) 656 * buffer: Where to read/write the data 657 * len: How many bytes to read/write 658 * 659 * Returns: 0 on success, not 0 on failure 660 */ 661 int i2c_read(uint8_t chip, unsigned int addr, int alen, 662 uint8_t *buffer, int len); 663 664 int i2c_write(uint8_t chip, unsigned int addr, int alen, 665 uint8_t *buffer, int len); 666 667 /* 668 * Utility routines to read/write registers. 669 */ 670 uint8_t i2c_reg_read(uint8_t addr, uint8_t reg); 671 672 void i2c_reg_write(uint8_t addr, uint8_t reg, uint8_t val); 673 674 /* 675 * i2c_set_bus_speed: 676 * 677 * Change the speed of the active I2C bus 678 * 679 * speed - bus speed in Hz 680 * 681 * Returns: new bus speed 682 * 683 */ 684 unsigned int i2c_set_bus_speed(unsigned int speed); 685 686 /* 687 * i2c_get_bus_speed: 688 * 689 * Returns speed of currently active I2C bus in Hz 690 */ 691 692 unsigned int i2c_get_bus_speed(void); 693 694 /* 695 * i2c_reloc_fixup: 696 * 697 * Adjusts I2C pointers after U-Boot is relocated to DRAM 698 */ 699 void i2c_reloc_fixup(void); 700 #if defined(CONFIG_SYS_I2C_SOFT) 701 void i2c_soft_init(void); 702 void i2c_soft_active(void); 703 void i2c_soft_tristate(void); 704 int i2c_soft_read(void); 705 void i2c_soft_sda(int bit); 706 void i2c_soft_scl(int bit); 707 void i2c_soft_delay(void); 708 #endif 709 #else 710 711 /* 712 * Probe the given I2C chip address. Returns 0 if a chip responded, 713 * not 0 on failure. 714 */ 715 int i2c_probe(uchar chip); 716 717 /* 718 * Read/Write interface: 719 * chip: I2C chip address, range 0..127 720 * addr: Memory (register) address within the chip 721 * alen: Number of bytes to use for addr (typically 1, 2 for larger 722 * memories, 0 for register type devices with only one 723 * register) 724 * buffer: Where to read/write the data 725 * len: How many bytes to read/write 726 * 727 * Returns: 0 on success, not 0 on failure 728 */ 729 int i2c_read(uchar chip, uint addr, int alen, uchar *buffer, int len); 730 int i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len); 731 732 /* 733 * Utility routines to read/write registers. 734 */ 735 static inline u8 i2c_reg_read(u8 addr, u8 reg) 736 { 737 u8 buf; 738 739 #ifdef CONFIG_8xx 740 /* MPC8xx needs this. Maybe one day we can get rid of it. */ 741 i2c_init(CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE); 742 #endif 743 744 #ifdef DEBUG 745 printf("%s: addr=0x%02x, reg=0x%02x\n", __func__, addr, reg); 746 #endif 747 748 i2c_read(addr, reg, 1, &buf, 1); 749 750 return buf; 751 } 752 753 static inline void i2c_reg_write(u8 addr, u8 reg, u8 val) 754 { 755 #ifdef CONFIG_8xx 756 /* MPC8xx needs this. Maybe one day we can get rid of it. */ 757 i2c_init(CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE); 758 #endif 759 760 #ifdef DEBUG 761 printf("%s: addr=0x%02x, reg=0x%02x, val=0x%02x\n", 762 __func__, addr, reg, val); 763 #endif 764 765 i2c_write(addr, reg, 1, &val, 1); 766 } 767 768 /* 769 * Functions for setting the current I2C bus and its speed 770 */ 771 772 /* 773 * i2c_set_bus_num: 774 * 775 * Change the active I2C bus. Subsequent read/write calls will 776 * go to this one. 777 * 778 * bus - bus index, zero based 779 * 780 * Returns: 0 on success, not 0 on failure 781 * 782 */ 783 int i2c_set_bus_num(unsigned int bus); 784 785 /* 786 * i2c_get_bus_num: 787 * 788 * Returns index of currently active I2C bus. Zero-based. 789 */ 790 791 unsigned int i2c_get_bus_num(void); 792 793 /* 794 * i2c_set_bus_speed: 795 * 796 * Change the speed of the active I2C bus 797 * 798 * speed - bus speed in Hz 799 * 800 * Returns: 0 on success, not 0 on failure 801 * 802 */ 803 int i2c_set_bus_speed(unsigned int); 804 805 /* 806 * i2c_get_bus_speed: 807 * 808 * Returns speed of currently active I2C bus in Hz 809 */ 810 811 unsigned int i2c_get_bus_speed(void); 812 #endif /* CONFIG_SYS_I2C */ 813 814 /* 815 * only for backwardcompatibility, should go away if we switched 816 * completely to new multibus support. 817 */ 818 #if defined(CONFIG_SYS_I2C) || defined(CONFIG_I2C_MULTI_BUS) 819 # if !defined(CONFIG_SYS_MAX_I2C_BUS) 820 # define CONFIG_SYS_MAX_I2C_BUS 2 821 # endif 822 # define I2C_MULTI_BUS 1 823 #else 824 # define CONFIG_SYS_MAX_I2C_BUS 1 825 # define I2C_MULTI_BUS 0 826 #endif 827 828 /* NOTE: These two functions MUST be always_inline to avoid code growth! */ 829 static inline unsigned int I2C_GET_BUS(void) __attribute__((always_inline)); 830 static inline unsigned int I2C_GET_BUS(void) 831 { 832 return I2C_MULTI_BUS ? i2c_get_bus_num() : 0; 833 } 834 835 static inline void I2C_SET_BUS(unsigned int bus) __attribute__((always_inline)); 836 static inline void I2C_SET_BUS(unsigned int bus) 837 { 838 if (I2C_MULTI_BUS) 839 i2c_set_bus_num(bus); 840 } 841 842 /* Multi I2C definitions */ 843 enum { 844 I2C_0, I2C_1, I2C_2, I2C_3, I2C_4, I2C_5, I2C_6, I2C_7, 845 I2C_8, I2C_9, I2C_10, 846 }; 847 848 /* Multi I2C busses handling */ 849 #ifdef CONFIG_SOFT_I2C_MULTI_BUS 850 extern int get_multi_scl_pin(void); 851 extern int get_multi_sda_pin(void); 852 extern int multi_i2c_init(void); 853 #endif 854 855 /** 856 * Get FDT values for i2c bus. 857 * 858 * @param blob Device tree blbo 859 * @return the number of I2C bus 860 */ 861 void board_i2c_init(const void *blob); 862 863 /** 864 * Find the I2C bus number by given a FDT I2C node. 865 * 866 * @param blob Device tree blbo 867 * @param node FDT I2C node to find 868 * @return the number of I2C bus (zero based), or -1 on error 869 */ 870 int i2c_get_bus_num_fdt(int node); 871 872 /** 873 * Reset the I2C bus represented by the given a FDT I2C node. 874 * 875 * @param blob Device tree blbo 876 * @param node FDT I2C node to find 877 * @return 0 if port was reset, -1 if not found 878 */ 879 int i2c_reset_port_fdt(const void *blob, int node); 880 881 #endif /* !CONFIG_DM_I2C */ 882 883 #endif /* _I2C_H_ */ 884