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 /** 324 * Set up a SPI slave for a particular device tree node 325 * 326 * This calls spi_setup_slave() with the correct bus number. Call 327 * spi_free_slave() to free it later. 328 * 329 * @param blob: Device tree blob 330 * @param slave_node: Slave node to use 331 * @param spi_node: SPI peripheral node to use 332 * @return pointer to new spi_slave structure 333 */ 334 struct spi_slave *spi_setup_slave_fdt(const void *blob, int slave_node, 335 int spi_node); 336 #ifdef CONFIG_DM_SPI 337 338 /** 339 * struct spi_cs_info - Information about a bus chip select 340 * 341 * @dev: Connected device, or NULL if none 342 */ 343 struct spi_cs_info { 344 struct udevice *dev; 345 }; 346 347 /** 348 * struct struct dm_spi_ops - Driver model SPI operations 349 * 350 * The uclass interface is implemented by all SPI devices which use 351 * driver model. 352 */ 353 struct dm_spi_ops { 354 /** 355 * Claim the bus and prepare it for communication. 356 * 357 * The device provided is the slave device. It's parent controller 358 * will be used to provide the communication. 359 * 360 * This must be called before doing any transfers with a SPI slave. It 361 * will enable and initialize any SPI hardware as necessary, and make 362 * sure that the SCK line is in the correct idle state. It is not 363 * allowed to claim the same bus for several slaves without releasing 364 * the bus in between. 365 * 366 * @dev: The SPI slave 367 * 368 * Returns: 0 if the bus was claimed successfully, or a negative value 369 * if it wasn't. 370 */ 371 int (*claim_bus)(struct udevice *dev); 372 373 /** 374 * Release the SPI bus 375 * 376 * This must be called once for every call to spi_claim_bus() after 377 * all transfers have finished. It may disable any SPI hardware as 378 * appropriate. 379 * 380 * @dev: The SPI slave 381 */ 382 int (*release_bus)(struct udevice *dev); 383 384 /** 385 * Set the word length for SPI transactions 386 * 387 * Set the word length (number of bits per word) for SPI transactions. 388 * 389 * @bus: The SPI slave 390 * @wordlen: The number of bits in a word 391 * 392 * Returns: 0 on success, -ve on failure. 393 */ 394 int (*set_wordlen)(struct udevice *dev, unsigned int wordlen); 395 396 /** 397 * SPI transfer 398 * 399 * This writes "bitlen" bits out the SPI MOSI port and simultaneously 400 * clocks "bitlen" bits in the SPI MISO port. That's just the way SPI 401 * works. 402 * 403 * The source of the outgoing bits is the "dout" parameter and the 404 * destination of the input bits is the "din" parameter. Note that 405 * "dout" and "din" can point to the same memory location, in which 406 * case the input data overwrites the output data (since both are 407 * buffered by temporary variables, this is OK). 408 * 409 * spi_xfer() interface: 410 * @dev: The slave device to communicate with 411 * @bitlen: How many bits to write and read. 412 * @dout: Pointer to a string of bits to send out. The bits are 413 * held in a byte array and are sent MSB first. 414 * @din: Pointer to a string of bits that will be filled in. 415 * @flags: A bitwise combination of SPI_XFER_* flags. 416 * 417 * Returns: 0 on success, not -1 on failure 418 */ 419 int (*xfer)(struct udevice *dev, unsigned int bitlen, const void *dout, 420 void *din, unsigned long flags); 421 422 /** 423 * Optimized handlers for SPI memory-like operations. 424 * 425 * Optimized/dedicated operations for interactions with SPI memory. This 426 * field is optional and should only be implemented if the controller 427 * has native support for memory like operations. 428 */ 429 const struct spi_controller_mem_ops *mem_ops; 430 431 /** 432 * Set transfer speed. 433 * This sets a new speed to be applied for next spi_xfer(). 434 * @bus: The SPI bus 435 * @hz: The transfer speed 436 * @return 0 if OK, -ve on error 437 */ 438 int (*set_speed)(struct udevice *bus, uint hz); 439 440 /** 441 * Set the SPI mode/flags 442 * 443 * It is unclear if we want to set speed and mode together instead 444 * of separately. 445 * 446 * @bus: The SPI bus 447 * @mode: Requested SPI mode (SPI_... flags) 448 * @return 0 if OK, -ve on error 449 */ 450 int (*set_mode)(struct udevice *bus, uint mode); 451 452 /** 453 * Get information on a chip select 454 * 455 * This is only called when the SPI uclass does not know about a 456 * chip select, i.e. it has no attached device. It gives the driver 457 * a chance to allow activity on that chip select even so. 458 * 459 * @bus: The SPI bus 460 * @cs: The chip select (0..n-1) 461 * @info: Returns information about the chip select, if valid. 462 * On entry info->dev is NULL 463 * @return 0 if OK (and @info is set up), -ENODEV if the chip select 464 * is invalid, other -ve value on error 465 */ 466 int (*cs_info)(struct udevice *bus, uint cs, struct spi_cs_info *info); 467 }; 468 469 struct dm_spi_emul_ops { 470 /** 471 * SPI transfer 472 * 473 * This writes "bitlen" bits out the SPI MOSI port and simultaneously 474 * clocks "bitlen" bits in the SPI MISO port. That's just the way SPI 475 * works. Here the device is a slave. 476 * 477 * The source of the outgoing bits is the "dout" parameter and the 478 * destination of the input bits is the "din" parameter. Note that 479 * "dout" and "din" can point to the same memory location, in which 480 * case the input data overwrites the output data (since both are 481 * buffered by temporary variables, this is OK). 482 * 483 * spi_xfer() interface: 484 * @slave: The SPI slave which will be sending/receiving the data. 485 * @bitlen: How many bits to write and read. 486 * @dout: Pointer to a string of bits sent to the device. The 487 * bits are held in a byte array and are sent MSB first. 488 * @din: Pointer to a string of bits that will be sent back to 489 * the master. 490 * @flags: A bitwise combination of SPI_XFER_* flags. 491 * 492 * Returns: 0 on success, not -1 on failure 493 */ 494 int (*xfer)(struct udevice *slave, unsigned int bitlen, 495 const void *dout, void *din, unsigned long flags); 496 }; 497 498 /** 499 * spi_find_bus_and_cs() - Find bus and slave devices by number 500 * 501 * Given a bus number and chip select, this finds the corresponding bus 502 * device and slave device. Neither device is activated by this function, 503 * although they may have been activated previously. 504 * 505 * @busnum: SPI bus number 506 * @cs: Chip select to look for 507 * @busp: Returns bus device 508 * @devp: Return slave device 509 * @return 0 if found, -ENODEV on error 510 */ 511 int spi_find_bus_and_cs(int busnum, int cs, struct udevice **busp, 512 struct udevice **devp); 513 514 /** 515 * spi_get_bus_and_cs() - Find and activate bus and slave devices by number 516 * 517 * Given a bus number and chip select, this finds the corresponding bus 518 * device and slave device. 519 * 520 * If no such slave exists, and drv_name is not NULL, then a new slave device 521 * is automatically bound on this chip select with requested speed and mode. 522 * 523 * Ths new slave device is probed ready for use with the speed and mode 524 * from platdata when available or the requested values. 525 * 526 * @busnum: SPI bus number 527 * @cs: Chip select to look for 528 * @speed: SPI speed to use for this slave when not available in platdata 529 * @mode: SPI mode to use for this slave when not available in platdata 530 * @drv_name: Name of driver to attach to this chip select 531 * @dev_name: Name of the new device thus created 532 * @busp: Returns bus device 533 * @devp: Return slave device 534 * @return 0 if found, -ve on error 535 */ 536 int spi_get_bus_and_cs(int busnum, int cs, int speed, int mode, 537 const char *drv_name, const char *dev_name, 538 struct udevice **busp, struct spi_slave **devp); 539 540 /** 541 * spi_chip_select() - Get the chip select for a slave 542 * 543 * @return the chip select this slave is attached to 544 */ 545 int spi_chip_select(struct udevice *slave); 546 547 /** 548 * spi_find_chip_select() - Find the slave attached to chip select 549 * 550 * @bus: SPI bus to search 551 * @cs: Chip select to look for 552 * @devp: Returns the slave device if found 553 * @return 0 if found, -ENODEV on error 554 */ 555 int spi_find_chip_select(struct udevice *bus, int cs, struct udevice **devp); 556 557 /** 558 * spi_slave_ofdata_to_platdata() - decode standard SPI platform data 559 * 560 * This decodes the speed and mode for a slave from a device tree node 561 * 562 * @blob: Device tree blob 563 * @node: Node offset to read from 564 * @plat: Place to put the decoded information 565 */ 566 int spi_slave_ofdata_to_platdata(struct udevice *dev, 567 struct dm_spi_slave_platdata *plat); 568 569 /** 570 * spi_cs_info() - Check information on a chip select 571 * 572 * This checks a particular chip select on a bus to see if it has a device 573 * attached, or is even valid. 574 * 575 * @bus: The SPI bus 576 * @cs: The chip select (0..n-1) 577 * @info: Returns information about the chip select, if valid 578 * @return 0 if OK (and @info is set up), -ENODEV if the chip select 579 * is invalid, other -ve value on error 580 */ 581 int spi_cs_info(struct udevice *bus, uint cs, struct spi_cs_info *info); 582 583 struct sandbox_state; 584 585 /** 586 * sandbox_spi_get_emul() - get an emulator for a SPI slave 587 * 588 * This provides a way to attach an emulated SPI device to a particular SPI 589 * slave, so that xfer() operations on the slave will be handled by the 590 * emulator. If a emulator already exists on that chip select it is returned. 591 * Otherwise one is created. 592 * 593 * @state: Sandbox state 594 * @bus: SPI bus requesting the emulator 595 * @slave: SPI slave device requesting the emulator 596 * @emuip: Returns pointer to emulator 597 * @return 0 if OK, -ve on error 598 */ 599 int sandbox_spi_get_emul(struct sandbox_state *state, 600 struct udevice *bus, struct udevice *slave, 601 struct udevice **emulp); 602 603 /** 604 * Claim the bus and prepare it for communication with a given slave. 605 * 606 * This must be called before doing any transfers with a SPI slave. It 607 * will enable and initialize any SPI hardware as necessary, and make 608 * sure that the SCK line is in the correct idle state. It is not 609 * allowed to claim the same bus for several slaves without releasing 610 * the bus in between. 611 * 612 * @dev: The SPI slave device 613 * 614 * Returns: 0 if the bus was claimed successfully, or a negative value 615 * if it wasn't. 616 */ 617 int dm_spi_claim_bus(struct udevice *dev); 618 619 /** 620 * Release the SPI bus 621 * 622 * This must be called once for every call to dm_spi_claim_bus() after 623 * all transfers have finished. It may disable any SPI hardware as 624 * appropriate. 625 * 626 * @slave: The SPI slave device 627 */ 628 void dm_spi_release_bus(struct udevice *dev); 629 630 /** 631 * SPI transfer 632 * 633 * This writes "bitlen" bits out the SPI MOSI port and simultaneously clocks 634 * "bitlen" bits in the SPI MISO port. That's just the way SPI works. 635 * 636 * The source of the outgoing bits is the "dout" parameter and the 637 * destination of the input bits is the "din" parameter. Note that "dout" 638 * and "din" can point to the same memory location, in which case the 639 * input data overwrites the output data (since both are buffered by 640 * temporary variables, this is OK). 641 * 642 * dm_spi_xfer() interface: 643 * @dev: The SPI slave device which will be sending/receiving the data. 644 * @bitlen: How many bits to write and read. 645 * @dout: Pointer to a string of bits to send out. The bits are 646 * held in a byte array and are sent MSB first. 647 * @din: Pointer to a string of bits that will be filled in. 648 * @flags: A bitwise combination of SPI_XFER_* flags. 649 * 650 * Returns: 0 on success, not 0 on failure 651 */ 652 int dm_spi_xfer(struct udevice *dev, unsigned int bitlen, 653 const void *dout, void *din, unsigned long flags); 654 655 /* Access the operations for a SPI device */ 656 #define spi_get_ops(dev) ((struct dm_spi_ops *)(dev)->driver->ops) 657 #define spi_emul_get_ops(dev) ((struct dm_spi_emul_ops *)(dev)->driver->ops) 658 #endif /* CONFIG_DM_SPI */ 659 660 #endif /* _SPI_H_ */ 661