1 /* 2 * Common SPI Interface: Controller-specific definitions 3 * 4 * (C) Copyright 2001 5 * Gerald Van Baren, Custom IDEAS, vanbaren@cideas.com. 6 * 7 * SPDX-License-Identifier: GPL-2.0+ 8 */ 9 10 #ifndef _SPI_H_ 11 #define _SPI_H_ 12 13 #include <common.h> 14 15 /* SPI mode flags */ 16 #define SPI_CPHA BIT(0) /* clock phase */ 17 #define SPI_CPOL BIT(1) /* clock polarity */ 18 #define SPI_MODE_0 (0|0) /* (original MicroWire) */ 19 #define SPI_MODE_1 (0|SPI_CPHA) 20 #define SPI_MODE_2 (SPI_CPOL|0) 21 #define SPI_MODE_3 (SPI_CPOL|SPI_CPHA) 22 #define SPI_CS_HIGH BIT(2) /* CS active high */ 23 #define SPI_LSB_FIRST BIT(3) /* per-word bits-on-wire */ 24 #define SPI_3WIRE BIT(4) /* SI/SO signals shared */ 25 #define SPI_LOOP BIT(5) /* loopback mode */ 26 #define SPI_SLAVE BIT(6) /* slave mode */ 27 #define SPI_PREAMBLE BIT(7) /* Skip preamble bytes */ 28 #define SPI_TX_BYTE BIT(8) /* transmit with 1 wire byte */ 29 #define SPI_TX_DUAL BIT(9) /* transmit with 2 wires */ 30 #define SPI_TX_QUAD BIT(10) /* transmit with 4 wires */ 31 #define SPI_RX_SLOW BIT(11) /* receive with 1 wire slow */ 32 #define SPI_RX_DUAL BIT(12) /* receive with 2 wires */ 33 #define SPI_RX_QUAD BIT(13) /* receive with 4 wires */ 34 35 /* Header byte that marks the start of the message */ 36 #define SPI_PREAMBLE_END_BYTE 0xec 37 38 #define SPI_DEFAULT_WORDLEN 8 39 40 #ifdef CONFIG_DM_SPI 41 /* TODO(sjg@chromium.org): Remove this and use max_hz from struct spi_slave */ 42 struct dm_spi_bus { 43 uint max_hz; 44 }; 45 46 /** 47 * struct dm_spi_platdata - platform data for all SPI slaves 48 * 49 * This describes a SPI slave, a child device of the SPI bus. To obtain this 50 * struct from a spi_slave, use dev_get_parent_platdata(dev) or 51 * dev_get_parent_platdata(slave->dev). 52 * 53 * This data is immuatable. Each time the device is probed, @max_hz and @mode 54 * will be copied to struct spi_slave. 55 * 56 * @cs: Chip select number (0..n-1) 57 * @max_hz: Maximum bus speed that this slave can tolerate 58 * @mode: SPI mode to use for this device (see SPI mode flags) 59 */ 60 struct dm_spi_slave_platdata { 61 unsigned int cs; 62 uint max_hz; 63 uint mode; 64 }; 65 66 #endif /* CONFIG_DM_SPI */ 67 68 /** 69 * struct spi_slave - Representation of a SPI slave 70 * 71 * For driver model this is the per-child data used by the SPI bus. It can 72 * be accessed using dev_get_parent_priv() on the slave device. The SPI uclass 73 * sets uip per_child_auto_alloc_size to sizeof(struct spi_slave), and the 74 * driver should not override it. Two platform data fields (max_hz and mode) 75 * are copied into this structure to provide an initial value. This allows 76 * them to be changed, since we should never change platform data in drivers. 77 * 78 * If not using driver model, drivers are expected to extend this with 79 * controller-specific data. 80 * 81 * @dev: SPI slave device 82 * @max_hz: Maximum speed for this slave 83 * @speed: Current bus speed. This is 0 until the bus is first 84 * claimed. 85 * @bus: ID of the bus that the slave is attached to. For 86 * driver model this is the sequence number of the SPI 87 * bus (bus->seq) so does not need to be stored 88 * @cs: ID of the chip select connected to the slave. 89 * @mode: SPI mode to use for this slave (see SPI mode flags) 90 * @wordlen: Size of SPI word in number of bits 91 * @max_read_size: If non-zero, the maximum number of bytes which can 92 * be read at once. 93 * @max_write_size: If non-zero, the maximum number of bytes which can 94 * be written at once. 95 * @memory_map: Address of read-only SPI flash access. 96 * @flags: Indication of SPI flags. 97 */ 98 struct spi_slave { 99 #ifdef CONFIG_DM_SPI 100 struct udevice *dev; /* struct spi_slave is dev->parentdata */ 101 uint max_hz; 102 uint speed; 103 #else 104 unsigned int bus; 105 unsigned int cs; 106 #endif 107 uint mode; 108 unsigned int wordlen; 109 unsigned int max_read_size; 110 unsigned int max_write_size; 111 void *memory_map; 112 u8 option; 113 114 u8 flags; 115 #define SPI_XFER_BEGIN BIT(0) /* Assert CS before transfer */ 116 #define SPI_XFER_END BIT(1) /* Deassert CS after transfer */ 117 #define SPI_XFER_ONCE (SPI_XFER_BEGIN | SPI_XFER_END) 118 #define SPI_XFER_MMAP BIT(2) /* Memory Mapped start */ 119 #define SPI_XFER_MMAP_END BIT(3) /* Memory Mapped End */ 120 }; 121 122 /** 123 * Initialization, must be called once on start up. 124 * 125 * TODO: I don't think we really need this. 126 */ 127 void spi_init(void); 128 129 /** 130 * spi_do_alloc_slave - Allocate a new SPI slave (internal) 131 * 132 * Allocate and zero all fields in the spi slave, and set the bus/chip 133 * select. Use the helper macro spi_alloc_slave() to call this. 134 * 135 * @offset: Offset of struct spi_slave within slave structure. 136 * @size: Size of slave structure. 137 * @bus: Bus ID of the slave chip. 138 * @cs: Chip select ID of the slave chip on the specified bus. 139 */ 140 void *spi_do_alloc_slave(int offset, int size, unsigned int bus, 141 unsigned int cs); 142 143 /** 144 * spi_alloc_slave - Allocate a new SPI slave 145 * 146 * Allocate and zero all fields in the spi slave, and set the bus/chip 147 * select. 148 * 149 * @_struct: Name of structure to allocate (e.g. struct tegra_spi). 150 * This structure must contain a member 'struct spi_slave *slave'. 151 * @bus: Bus ID of the slave chip. 152 * @cs: Chip select ID of the slave chip on the specified bus. 153 */ 154 #define spi_alloc_slave(_struct, bus, cs) \ 155 spi_do_alloc_slave(offsetof(_struct, slave), \ 156 sizeof(_struct), bus, cs) 157 158 /** 159 * spi_alloc_slave_base - Allocate a new SPI slave with no private data 160 * 161 * Allocate and zero all fields in the spi slave, and set the bus/chip 162 * select. 163 * 164 * @bus: Bus ID of the slave chip. 165 * @cs: Chip select ID of the slave chip on the specified bus. 166 */ 167 #define spi_alloc_slave_base(bus, cs) \ 168 spi_do_alloc_slave(0, sizeof(struct spi_slave), bus, cs) 169 170 /** 171 * Set up communications parameters for a SPI slave. 172 * 173 * This must be called once for each slave. Note that this function 174 * usually doesn't touch any actual hardware, it only initializes the 175 * contents of spi_slave so that the hardware can be easily 176 * initialized later. 177 * 178 * @bus: Bus ID of the slave chip. 179 * @cs: Chip select ID of the slave chip on the specified bus. 180 * @max_hz: Maximum SCK rate in Hz. 181 * @mode: Clock polarity, clock phase and other parameters. 182 * 183 * Returns: A spi_slave reference that can be used in subsequent SPI 184 * calls, or NULL if one or more of the parameters are not supported. 185 */ 186 struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs, 187 unsigned int max_hz, unsigned int mode); 188 189 /** 190 * Free any memory associated with a SPI slave. 191 * 192 * @slave: The SPI slave 193 */ 194 void spi_free_slave(struct spi_slave *slave); 195 196 /** 197 * Claim the bus and prepare it for communication with a given slave. 198 * 199 * This must be called before doing any transfers with a SPI slave. It 200 * will enable and initialize any SPI hardware as necessary, and make 201 * sure that the SCK line is in the correct idle state. It is not 202 * allowed to claim the same bus for several slaves without releasing 203 * the bus in between. 204 * 205 * @slave: The SPI slave 206 * 207 * Returns: 0 if the bus was claimed successfully, or a negative value 208 * if it wasn't. 209 */ 210 int spi_claim_bus(struct spi_slave *slave); 211 212 /** 213 * Release the SPI bus 214 * 215 * This must be called once for every call to spi_claim_bus() after 216 * all transfers have finished. It may disable any SPI hardware as 217 * appropriate. 218 * 219 * @slave: The SPI slave 220 */ 221 void spi_release_bus(struct spi_slave *slave); 222 223 /** 224 * Set the word length for SPI transactions 225 * 226 * Set the word length (number of bits per word) for SPI transactions. 227 * 228 * @slave: The SPI slave 229 * @wordlen: The number of bits in a word 230 * 231 * Returns: 0 on success, -1 on failure. 232 */ 233 int spi_set_wordlen(struct spi_slave *slave, unsigned int wordlen); 234 235 /** 236 * SPI transfer 237 * 238 * This writes "bitlen" bits out the SPI MOSI port and simultaneously clocks 239 * "bitlen" bits in the SPI MISO port. That's just the way SPI works. 240 * 241 * The source of the outgoing bits is the "dout" parameter and the 242 * destination of the input bits is the "din" parameter. Note that "dout" 243 * and "din" can point to the same memory location, in which case the 244 * input data overwrites the output data (since both are buffered by 245 * temporary variables, this is OK). 246 * 247 * spi_xfer() interface: 248 * @slave: The SPI slave which will be sending/receiving the data. 249 * @bitlen: How many bits to write and read. 250 * @dout: Pointer to a string of bits to send out. The bits are 251 * held in a byte array and are sent MSB first. 252 * @din: Pointer to a string of bits that will be filled in. 253 * @flags: A bitwise combination of SPI_XFER_* flags. 254 * 255 * Returns: 0 on success, not 0 on failure 256 */ 257 int spi_xfer(struct spi_slave *slave, unsigned int bitlen, const void *dout, 258 void *din, unsigned long flags); 259 260 /* Copy memory mapped data */ 261 void spi_flash_copy_mmap(void *data, void *offset, size_t len); 262 263 /** 264 * Determine if a SPI chipselect is valid. 265 * This function is provided by the board if the low-level SPI driver 266 * needs it to determine if a given chipselect is actually valid. 267 * 268 * Returns: 1 if bus:cs identifies a valid chip on this board, 0 269 * otherwise. 270 */ 271 int spi_cs_is_valid(unsigned int bus, unsigned int cs); 272 273 #ifndef CONFIG_DM_SPI 274 /** 275 * Activate a SPI chipselect. 276 * This function is provided by the board code when using a driver 277 * that can't control its chipselects automatically (e.g. 278 * common/soft_spi.c). When called, it should activate the chip select 279 * to the device identified by "slave". 280 */ 281 void spi_cs_activate(struct spi_slave *slave); 282 283 /** 284 * Deactivate a SPI chipselect. 285 * This function is provided by the board code when using a driver 286 * that can't control its chipselects automatically (e.g. 287 * common/soft_spi.c). When called, it should deactivate the chip 288 * select to the device identified by "slave". 289 */ 290 void spi_cs_deactivate(struct spi_slave *slave); 291 292 /** 293 * Set transfer speed. 294 * This sets a new speed to be applied for next spi_xfer(). 295 * @slave: The SPI slave 296 * @hz: The transfer speed 297 */ 298 void spi_set_speed(struct spi_slave *slave, uint hz); 299 #endif 300 301 /** 302 * Write 8 bits, then read 8 bits. 303 * @slave: The SPI slave we're communicating with 304 * @byte: Byte to be written 305 * 306 * Returns: The value that was read, or a negative value on error. 307 * 308 * TODO: This function probably shouldn't be inlined. 309 */ 310 static inline int spi_w8r8(struct spi_slave *slave, unsigned char byte) 311 { 312 unsigned char dout[2]; 313 unsigned char din[2]; 314 int ret; 315 316 dout[0] = byte; 317 dout[1] = 0; 318 319 ret = spi_xfer(slave, 16, dout, din, SPI_XFER_BEGIN | SPI_XFER_END); 320 return ret < 0 ? ret : din[1]; 321 } 322 323 #ifdef CONFIG_DM_SPI 324 325 /** 326 * struct spi_cs_info - Information about a bus chip select 327 * 328 * @dev: Connected device, or NULL if none 329 */ 330 struct spi_cs_info { 331 struct udevice *dev; 332 }; 333 334 /** 335 * struct struct dm_spi_ops - Driver model SPI operations 336 * 337 * The uclass interface is implemented by all SPI devices which use 338 * driver model. 339 */ 340 struct dm_spi_ops { 341 /** 342 * Claim the bus and prepare it for communication. 343 * 344 * The device provided is the slave device. It's parent controller 345 * will be used to provide the communication. 346 * 347 * This must be called before doing any transfers with a SPI slave. It 348 * will enable and initialize any SPI hardware as necessary, and make 349 * sure that the SCK line is in the correct idle state. It is not 350 * allowed to claim the same bus for several slaves without releasing 351 * the bus in between. 352 * 353 * @dev: The SPI slave 354 * 355 * Returns: 0 if the bus was claimed successfully, or a negative value 356 * if it wasn't. 357 */ 358 int (*claim_bus)(struct udevice *dev); 359 360 /** 361 * Release the SPI bus 362 * 363 * This must be called once for every call to spi_claim_bus() after 364 * all transfers have finished. It may disable any SPI hardware as 365 * appropriate. 366 * 367 * @dev: The SPI slave 368 */ 369 int (*release_bus)(struct udevice *dev); 370 371 /** 372 * Set the word length for SPI transactions 373 * 374 * Set the word length (number of bits per word) for SPI transactions. 375 * 376 * @bus: The SPI slave 377 * @wordlen: The number of bits in a word 378 * 379 * Returns: 0 on success, -ve on failure. 380 */ 381 int (*set_wordlen)(struct udevice *dev, unsigned int wordlen); 382 383 /** 384 * SPI transfer 385 * 386 * This writes "bitlen" bits out the SPI MOSI port and simultaneously 387 * clocks "bitlen" bits in the SPI MISO port. That's just the way SPI 388 * works. 389 * 390 * The source of the outgoing bits is the "dout" parameter and the 391 * destination of the input bits is the "din" parameter. Note that 392 * "dout" and "din" can point to the same memory location, in which 393 * case the input data overwrites the output data (since both are 394 * buffered by temporary variables, this is OK). 395 * 396 * spi_xfer() interface: 397 * @dev: The slave device to communicate with 398 * @bitlen: How many bits to write and read. 399 * @dout: Pointer to a string of bits to send out. The bits are 400 * held in a byte array and are sent MSB first. 401 * @din: Pointer to a string of bits that will be filled in. 402 * @flags: A bitwise combination of SPI_XFER_* flags. 403 * 404 * Returns: 0 on success, not -1 on failure 405 */ 406 int (*xfer)(struct udevice *dev, unsigned int bitlen, const void *dout, 407 void *din, unsigned long flags); 408 409 /** 410 * Optimized handlers for SPI memory-like operations. 411 * 412 * Optimized/dedicated operations for interactions with SPI memory. This 413 * field is optional and should only be implemented if the controller 414 * has native support for memory like operations. 415 */ 416 const struct spi_controller_mem_ops *mem_ops; 417 418 /** 419 * Set transfer speed. 420 * This sets a new speed to be applied for next spi_xfer(). 421 * @bus: The SPI bus 422 * @hz: The transfer speed 423 * @return 0 if OK, -ve on error 424 */ 425 int (*set_speed)(struct udevice *bus, uint hz); 426 427 /** 428 * Set the SPI mode/flags 429 * 430 * It is unclear if we want to set speed and mode together instead 431 * of separately. 432 * 433 * @bus: The SPI bus 434 * @mode: Requested SPI mode (SPI_... flags) 435 * @return 0 if OK, -ve on error 436 */ 437 int (*set_mode)(struct udevice *bus, uint mode); 438 439 /** 440 * Get information on a chip select 441 * 442 * This is only called when the SPI uclass does not know about a 443 * chip select, i.e. it has no attached device. It gives the driver 444 * a chance to allow activity on that chip select even so. 445 * 446 * @bus: The SPI bus 447 * @cs: The chip select (0..n-1) 448 * @info: Returns information about the chip select, if valid. 449 * On entry info->dev is NULL 450 * @return 0 if OK (and @info is set up), -ENODEV if the chip select 451 * is invalid, other -ve value on error 452 */ 453 int (*cs_info)(struct udevice *bus, uint cs, struct spi_cs_info *info); 454 }; 455 456 struct dm_spi_emul_ops { 457 /** 458 * SPI transfer 459 * 460 * This writes "bitlen" bits out the SPI MOSI port and simultaneously 461 * clocks "bitlen" bits in the SPI MISO port. That's just the way SPI 462 * works. Here the device is a slave. 463 * 464 * The source of the outgoing bits is the "dout" parameter and the 465 * destination of the input bits is the "din" parameter. Note that 466 * "dout" and "din" can point to the same memory location, in which 467 * case the input data overwrites the output data (since both are 468 * buffered by temporary variables, this is OK). 469 * 470 * spi_xfer() interface: 471 * @slave: The SPI slave which will be sending/receiving the data. 472 * @bitlen: How many bits to write and read. 473 * @dout: Pointer to a string of bits sent to the device. The 474 * bits are held in a byte array and are sent MSB first. 475 * @din: Pointer to a string of bits that will be sent back to 476 * the master. 477 * @flags: A bitwise combination of SPI_XFER_* flags. 478 * 479 * Returns: 0 on success, not -1 on failure 480 */ 481 int (*xfer)(struct udevice *slave, unsigned int bitlen, 482 const void *dout, void *din, unsigned long flags); 483 }; 484 485 /** 486 * spi_find_bus_and_cs() - Find bus and slave devices by number 487 * 488 * Given a bus number and chip select, this finds the corresponding bus 489 * device and slave device. Neither device is activated by this function, 490 * although they may have been activated previously. 491 * 492 * @busnum: SPI bus number 493 * @cs: Chip select to look for 494 * @busp: Returns bus device 495 * @devp: Return slave device 496 * @return 0 if found, -ENODEV on error 497 */ 498 int spi_find_bus_and_cs(int busnum, int cs, struct udevice **busp, 499 struct udevice **devp); 500 501 /** 502 * spi_get_bus_and_cs() - Find and activate bus and slave devices by number 503 * 504 * Given a bus number and chip select, this finds the corresponding bus 505 * device and slave device. 506 * 507 * If no such slave exists, and drv_name is not NULL, then a new slave device 508 * is automatically bound on this chip select with requested speed and mode. 509 * 510 * Ths new slave device is probed ready for use with the speed and mode 511 * from platdata when available or the requested values. 512 * 513 * @busnum: SPI bus number 514 * @cs: Chip select to look for 515 * @speed: SPI speed to use for this slave when not available in platdata 516 * @mode: SPI mode to use for this slave when not available in platdata 517 * @drv_name: Name of driver to attach to this chip select 518 * @dev_name: Name of the new device thus created 519 * @busp: Returns bus device 520 * @devp: Return slave device 521 * @return 0 if found, -ve on error 522 */ 523 int spi_get_bus_and_cs(int busnum, int cs, int speed, int mode, 524 const char *drv_name, const char *dev_name, 525 struct udevice **busp, struct spi_slave **devp); 526 527 /** 528 * spi_chip_select() - Get the chip select for a slave 529 * 530 * @return the chip select this slave is attached to 531 */ 532 int spi_chip_select(struct udevice *slave); 533 534 /** 535 * spi_find_chip_select() - Find the slave attached to chip select 536 * 537 * @bus: SPI bus to search 538 * @cs: Chip select to look for 539 * @devp: Returns the slave device if found 540 * @return 0 if found, -ENODEV on error 541 */ 542 int spi_find_chip_select(struct udevice *bus, int cs, struct udevice **devp); 543 544 /** 545 * spi_slave_ofdata_to_platdata() - decode standard SPI platform data 546 * 547 * This decodes the speed and mode for a slave from a device tree node 548 * 549 * @blob: Device tree blob 550 * @node: Node offset to read from 551 * @plat: Place to put the decoded information 552 */ 553 int spi_slave_ofdata_to_platdata(struct udevice *dev, 554 struct dm_spi_slave_platdata *plat); 555 556 /** 557 * spi_cs_info() - Check information on a chip select 558 * 559 * This checks a particular chip select on a bus to see if it has a device 560 * attached, or is even valid. 561 * 562 * @bus: The SPI bus 563 * @cs: The chip select (0..n-1) 564 * @info: Returns information about the chip select, if valid 565 * @return 0 if OK (and @info is set up), -ENODEV if the chip select 566 * is invalid, other -ve value on error 567 */ 568 int spi_cs_info(struct udevice *bus, uint cs, struct spi_cs_info *info); 569 570 struct sandbox_state; 571 572 /** 573 * sandbox_spi_get_emul() - get an emulator for a SPI slave 574 * 575 * This provides a way to attach an emulated SPI device to a particular SPI 576 * slave, so that xfer() operations on the slave will be handled by the 577 * emulator. If a emulator already exists on that chip select it is returned. 578 * Otherwise one is created. 579 * 580 * @state: Sandbox state 581 * @bus: SPI bus requesting the emulator 582 * @slave: SPI slave device requesting the emulator 583 * @emuip: Returns pointer to emulator 584 * @return 0 if OK, -ve on error 585 */ 586 int sandbox_spi_get_emul(struct sandbox_state *state, 587 struct udevice *bus, struct udevice *slave, 588 struct udevice **emulp); 589 590 /** 591 * Claim the bus and prepare it for communication with a given slave. 592 * 593 * This must be called before doing any transfers with a SPI slave. It 594 * will enable and initialize any SPI hardware as necessary, and make 595 * sure that the SCK line is in the correct idle state. It is not 596 * allowed to claim the same bus for several slaves without releasing 597 * the bus in between. 598 * 599 * @dev: The SPI slave device 600 * 601 * Returns: 0 if the bus was claimed successfully, or a negative value 602 * if it wasn't. 603 */ 604 int dm_spi_claim_bus(struct udevice *dev); 605 606 /** 607 * Release the SPI bus 608 * 609 * This must be called once for every call to dm_spi_claim_bus() after 610 * all transfers have finished. It may disable any SPI hardware as 611 * appropriate. 612 * 613 * @slave: The SPI slave device 614 */ 615 void dm_spi_release_bus(struct udevice *dev); 616 617 /** 618 * SPI transfer 619 * 620 * This writes "bitlen" bits out the SPI MOSI port and simultaneously clocks 621 * "bitlen" bits in the SPI MISO port. That's just the way SPI works. 622 * 623 * The source of the outgoing bits is the "dout" parameter and the 624 * destination of the input bits is the "din" parameter. Note that "dout" 625 * and "din" can point to the same memory location, in which case the 626 * input data overwrites the output data (since both are buffered by 627 * temporary variables, this is OK). 628 * 629 * dm_spi_xfer() interface: 630 * @dev: The SPI slave device which will be sending/receiving the data. 631 * @bitlen: How many bits to write and read. 632 * @dout: Pointer to a string of bits to send out. The bits are 633 * held in a byte array and are sent MSB first. 634 * @din: Pointer to a string of bits that will be filled in. 635 * @flags: A bitwise combination of SPI_XFER_* flags. 636 * 637 * Returns: 0 on success, not 0 on failure 638 */ 639 int dm_spi_xfer(struct udevice *dev, unsigned int bitlen, 640 const void *dout, void *din, unsigned long flags); 641 642 /* Access the operations for a SPI device */ 643 #define spi_get_ops(dev) ((struct dm_spi_ops *)(dev)->driver->ops) 644 #define spi_emul_get_ops(dev) ((struct dm_spi_emul_ops *)(dev)->driver->ops) 645 #endif /* CONFIG_DM_SPI */ 646 647 #endif /* _SPI_H_ */ 648