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 /* SPI mode flags */ 14 #define SPI_CPHA BIT(0) /* clock phase */ 15 #define SPI_CPOL BIT(1) /* clock polarity */ 16 #define SPI_MODE_0 (0|0) /* (original MicroWire) */ 17 #define SPI_MODE_1 (0|SPI_CPHA) 18 #define SPI_MODE_2 (SPI_CPOL|0) 19 #define SPI_MODE_3 (SPI_CPOL|SPI_CPHA) 20 #define SPI_CS_HIGH BIT(2) /* CS active high */ 21 #define SPI_LSB_FIRST BIT(3) /* per-word bits-on-wire */ 22 #define SPI_3WIRE BIT(4) /* SI/SO signals shared */ 23 #define SPI_LOOP BIT(5) /* loopback mode */ 24 #define SPI_SLAVE BIT(6) /* slave mode */ 25 #define SPI_PREAMBLE BIT(7) /* Skip preamble bytes */ 26 #define SPI_TX_BYTE BIT(8) /* transmit with 1 wire byte */ 27 #define SPI_TX_DUAL BIT(9) /* transmit with 2 wires */ 28 #define SPI_TX_QUAD BIT(10) /* transmit with 4 wires */ 29 #define SPI_RX_SLOW BIT(11) /* receive with 1 wire slow */ 30 #define SPI_RX_DUAL BIT(12) /* receive with 2 wires */ 31 #define SPI_RX_QUAD BIT(13) /* receive with 4 wires */ 32 33 /* Header byte that marks the start of the message */ 34 #define SPI_PREAMBLE_END_BYTE 0xec 35 36 #define SPI_DEFAULT_WORDLEN 8 37 38 #ifdef CONFIG_DM_SPI 39 /* TODO(sjg@chromium.org): Remove this and use max_hz from struct spi_slave */ 40 struct dm_spi_bus { 41 uint max_hz; 42 }; 43 44 /** 45 * struct dm_spi_platdata - platform data for all SPI slaves 46 * 47 * This describes a SPI slave, a child device of the SPI bus. To obtain this 48 * struct from a spi_slave, use dev_get_parent_platdata(dev) or 49 * dev_get_parent_platdata(slave->dev). 50 * 51 * This data is immuatable. Each time the device is probed, @max_hz and @mode 52 * will be copied to struct spi_slave. 53 * 54 * @cs: Chip select number (0..n-1) 55 * @max_hz: Maximum bus speed that this slave can tolerate 56 * @mode: SPI mode to use for this device (see SPI mode flags) 57 */ 58 struct dm_spi_slave_platdata { 59 unsigned int cs; 60 uint max_hz; 61 uint mode; 62 }; 63 64 #endif /* CONFIG_DM_SPI */ 65 66 /** 67 * struct spi_slave - Representation of a SPI slave 68 * 69 * For driver model this is the per-child data used by the SPI bus. It can 70 * be accessed using dev_get_parent_priv() on the slave device. The SPI uclass 71 * sets uip per_child_auto_alloc_size to sizeof(struct spi_slave), and the 72 * driver should not override it. Two platform data fields (max_hz and mode) 73 * are copied into this structure to provide an initial value. This allows 74 * them to be changed, since we should never change platform data in drivers. 75 * 76 * If not using driver model, drivers are expected to extend this with 77 * controller-specific data. 78 * 79 * @dev: SPI slave device 80 * @max_hz: Maximum speed for this slave 81 * @speed: Current bus speed. This is 0 until the bus is first 82 * claimed. 83 * @bus: ID of the bus that the slave is attached to. For 84 * driver model this is the sequence number of the SPI 85 * bus (bus->seq) so does not need to be stored 86 * @cs: ID of the chip select connected to the slave. 87 * @mode: SPI mode to use for this slave (see SPI mode flags) 88 * @wordlen: Size of SPI word in number of bits 89 * @max_read_size: If non-zero, the maximum number of bytes which can 90 * be read at once. 91 * @max_write_size: If non-zero, the maximum number of bytes which can 92 * be written at once. 93 * @memory_map: Address of read-only SPI flash access. 94 * @flags: Indication of SPI flags. 95 */ 96 struct spi_slave { 97 #ifdef CONFIG_DM_SPI 98 struct udevice *dev; /* struct spi_slave is dev->parentdata */ 99 uint max_hz; 100 uint speed; 101 #else 102 unsigned int bus; 103 unsigned int cs; 104 #endif 105 uint mode; 106 unsigned int wordlen; 107 unsigned int max_read_size; 108 unsigned int max_write_size; 109 void *memory_map; 110 u8 option; 111 112 u8 flags; 113 #define SPI_XFER_BEGIN BIT(0) /* Assert CS before transfer */ 114 #define SPI_XFER_END BIT(1) /* Deassert CS after transfer */ 115 #define SPI_XFER_ONCE (SPI_XFER_BEGIN | SPI_XFER_END) 116 #define SPI_XFER_MMAP BIT(2) /* Memory Mapped start */ 117 #define SPI_XFER_MMAP_END BIT(3) /* Memory Mapped End */ 118 }; 119 120 /** 121 * Initialization, must be called once on start up. 122 * 123 * TODO: I don't think we really need this. 124 */ 125 void spi_init(void); 126 127 /** 128 * spi_do_alloc_slave - Allocate a new SPI slave (internal) 129 * 130 * Allocate and zero all fields in the spi slave, and set the bus/chip 131 * select. Use the helper macro spi_alloc_slave() to call this. 132 * 133 * @offset: Offset of struct spi_slave within slave structure. 134 * @size: Size of slave structure. 135 * @bus: Bus ID of the slave chip. 136 * @cs: Chip select ID of the slave chip on the specified bus. 137 */ 138 void *spi_do_alloc_slave(int offset, int size, unsigned int bus, 139 unsigned int cs); 140 141 /** 142 * spi_alloc_slave - Allocate a new SPI slave 143 * 144 * Allocate and zero all fields in the spi slave, and set the bus/chip 145 * select. 146 * 147 * @_struct: Name of structure to allocate (e.g. struct tegra_spi). 148 * This structure must contain a member 'struct spi_slave *slave'. 149 * @bus: Bus ID of the slave chip. 150 * @cs: Chip select ID of the slave chip on the specified bus. 151 */ 152 #define spi_alloc_slave(_struct, bus, cs) \ 153 spi_do_alloc_slave(offsetof(_struct, slave), \ 154 sizeof(_struct), bus, cs) 155 156 /** 157 * spi_alloc_slave_base - Allocate a new SPI slave with no private data 158 * 159 * Allocate and zero all fields in the spi slave, and set the bus/chip 160 * select. 161 * 162 * @bus: Bus ID of the slave chip. 163 * @cs: Chip select ID of the slave chip on the specified bus. 164 */ 165 #define spi_alloc_slave_base(bus, cs) \ 166 spi_do_alloc_slave(0, sizeof(struct spi_slave), bus, cs) 167 168 /** 169 * Set up communications parameters for a SPI slave. 170 * 171 * This must be called once for each slave. Note that this function 172 * usually doesn't touch any actual hardware, it only initializes the 173 * contents of spi_slave so that the hardware can be easily 174 * initialized later. 175 * 176 * @bus: Bus ID of the slave chip. 177 * @cs: Chip select ID of the slave chip on the specified bus. 178 * @max_hz: Maximum SCK rate in Hz. 179 * @mode: Clock polarity, clock phase and other parameters. 180 * 181 * Returns: A spi_slave reference that can be used in subsequent SPI 182 * calls, or NULL if one or more of the parameters are not supported. 183 */ 184 struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs, 185 unsigned int max_hz, unsigned int mode); 186 187 /** 188 * Free any memory associated with a SPI slave. 189 * 190 * @slave: The SPI slave 191 */ 192 void spi_free_slave(struct spi_slave *slave); 193 194 /** 195 * Claim the bus and prepare it for communication with a given slave. 196 * 197 * This must be called before doing any transfers with a SPI slave. It 198 * will enable and initialize any SPI hardware as necessary, and make 199 * sure that the SCK line is in the correct idle state. It is not 200 * allowed to claim the same bus for several slaves without releasing 201 * the bus in between. 202 * 203 * @slave: The SPI slave 204 * 205 * Returns: 0 if the bus was claimed successfully, or a negative value 206 * if it wasn't. 207 */ 208 int spi_claim_bus(struct spi_slave *slave); 209 210 /** 211 * Release the SPI bus 212 * 213 * This must be called once for every call to spi_claim_bus() after 214 * all transfers have finished. It may disable any SPI hardware as 215 * appropriate. 216 * 217 * @slave: The SPI slave 218 */ 219 void spi_release_bus(struct spi_slave *slave); 220 221 /** 222 * Set the word length for SPI transactions 223 * 224 * Set the word length (number of bits per word) for SPI transactions. 225 * 226 * @slave: The SPI slave 227 * @wordlen: The number of bits in a word 228 * 229 * Returns: 0 on success, -1 on failure. 230 */ 231 int spi_set_wordlen(struct spi_slave *slave, unsigned int wordlen); 232 233 /** 234 * SPI transfer 235 * 236 * This writes "bitlen" bits out the SPI MOSI port and simultaneously clocks 237 * "bitlen" bits in the SPI MISO port. That's just the way SPI works. 238 * 239 * The source of the outgoing bits is the "dout" parameter and the 240 * destination of the input bits is the "din" parameter. Note that "dout" 241 * and "din" can point to the same memory location, in which case the 242 * input data overwrites the output data (since both are buffered by 243 * temporary variables, this is OK). 244 * 245 * spi_xfer() interface: 246 * @slave: The SPI slave which will be sending/receiving the data. 247 * @bitlen: How many bits to write and read. 248 * @dout: Pointer to a string of bits to send out. The bits are 249 * held in a byte array and are sent MSB first. 250 * @din: Pointer to a string of bits that will be filled in. 251 * @flags: A bitwise combination of SPI_XFER_* flags. 252 * 253 * Returns: 0 on success, not 0 on failure 254 */ 255 int spi_xfer(struct spi_slave *slave, unsigned int bitlen, const void *dout, 256 void *din, unsigned long flags); 257 258 /* Copy memory mapped data */ 259 void spi_flash_copy_mmap(void *data, void *offset, size_t len); 260 261 /** 262 * Determine if a SPI chipselect is valid. 263 * This function is provided by the board if the low-level SPI driver 264 * needs it to determine if a given chipselect is actually valid. 265 * 266 * Returns: 1 if bus:cs identifies a valid chip on this board, 0 267 * otherwise. 268 */ 269 int spi_cs_is_valid(unsigned int bus, unsigned int cs); 270 271 #ifndef CONFIG_DM_SPI 272 /** 273 * Activate a SPI chipselect. 274 * This function is provided by the board code when using a driver 275 * that can't control its chipselects automatically (e.g. 276 * common/soft_spi.c). When called, it should activate the chip select 277 * to the device identified by "slave". 278 */ 279 void spi_cs_activate(struct spi_slave *slave); 280 281 /** 282 * Deactivate a SPI chipselect. 283 * This function is provided by the board code when using a driver 284 * that can't control its chipselects automatically (e.g. 285 * common/soft_spi.c). When called, it should deactivate the chip 286 * select to the device identified by "slave". 287 */ 288 void spi_cs_deactivate(struct spi_slave *slave); 289 290 /** 291 * Set transfer speed. 292 * This sets a new speed to be applied for next spi_xfer(). 293 * @slave: The SPI slave 294 * @hz: The transfer speed 295 */ 296 void spi_set_speed(struct spi_slave *slave, uint hz); 297 #endif 298 299 /** 300 * Write 8 bits, then read 8 bits. 301 * @slave: The SPI slave we're communicating with 302 * @byte: Byte to be written 303 * 304 * Returns: The value that was read, or a negative value on error. 305 * 306 * TODO: This function probably shouldn't be inlined. 307 */ 308 static inline int spi_w8r8(struct spi_slave *slave, unsigned char byte) 309 { 310 unsigned char dout[2]; 311 unsigned char din[2]; 312 int ret; 313 314 dout[0] = byte; 315 dout[1] = 0; 316 317 ret = spi_xfer(slave, 16, dout, din, SPI_XFER_BEGIN | SPI_XFER_END); 318 return ret < 0 ? ret : din[1]; 319 } 320 321 /** 322 * Set up a SPI slave for a particular device tree node 323 * 324 * This calls spi_setup_slave() with the correct bus number. Call 325 * spi_free_slave() to free it later. 326 * 327 * @param blob: Device tree blob 328 * @param slave_node: Slave node to use 329 * @param spi_node: SPI peripheral node to use 330 * @return pointer to new spi_slave structure 331 */ 332 struct spi_slave *spi_setup_slave_fdt(const void *blob, int slave_node, 333 int spi_node); 334 335 /** 336 * spi_base_setup_slave_fdt() - helper function to set up a SPI slace 337 * 338 * This decodes SPI properties from the slave node to determine the 339 * chip select and SPI parameters. 340 * 341 * @blob: Device tree blob 342 * @busnum: Bus number to use 343 * @node: Device tree node for the SPI bus 344 */ 345 struct spi_slave *spi_base_setup_slave_fdt(const void *blob, int busnum, 346 int node); 347 348 #ifdef CONFIG_DM_SPI 349 350 /** 351 * struct spi_cs_info - Information about a bus chip select 352 * 353 * @dev: Connected device, or NULL if none 354 */ 355 struct spi_cs_info { 356 struct udevice *dev; 357 }; 358 359 /** 360 * struct struct dm_spi_ops - Driver model SPI operations 361 * 362 * The uclass interface is implemented by all SPI devices which use 363 * driver model. 364 */ 365 struct dm_spi_ops { 366 /** 367 * Claim the bus and prepare it for communication. 368 * 369 * The device provided is the slave device. It's parent controller 370 * will be used to provide the communication. 371 * 372 * This must be called before doing any transfers with a SPI slave. It 373 * will enable and initialize any SPI hardware as necessary, and make 374 * sure that the SCK line is in the correct idle state. It is not 375 * allowed to claim the same bus for several slaves without releasing 376 * the bus in between. 377 * 378 * @dev: The SPI slave 379 * 380 * Returns: 0 if the bus was claimed successfully, or a negative value 381 * if it wasn't. 382 */ 383 int (*claim_bus)(struct udevice *dev); 384 385 /** 386 * Release the SPI bus 387 * 388 * This must be called once for every call to spi_claim_bus() after 389 * all transfers have finished. It may disable any SPI hardware as 390 * appropriate. 391 * 392 * @dev: The SPI slave 393 */ 394 int (*release_bus)(struct udevice *dev); 395 396 /** 397 * Set the word length for SPI transactions 398 * 399 * Set the word length (number of bits per word) for SPI transactions. 400 * 401 * @bus: The SPI slave 402 * @wordlen: The number of bits in a word 403 * 404 * Returns: 0 on success, -ve on failure. 405 */ 406 int (*set_wordlen)(struct udevice *dev, unsigned int wordlen); 407 408 /** 409 * SPI transfer 410 * 411 * This writes "bitlen" bits out the SPI MOSI port and simultaneously 412 * clocks "bitlen" bits in the SPI MISO port. That's just the way SPI 413 * works. 414 * 415 * The source of the outgoing bits is the "dout" parameter and the 416 * destination of the input bits is the "din" parameter. Note that 417 * "dout" and "din" can point to the same memory location, in which 418 * case the input data overwrites the output data (since both are 419 * buffered by temporary variables, this is OK). 420 * 421 * spi_xfer() interface: 422 * @dev: The slave device to communicate with 423 * @bitlen: How many bits to write and read. 424 * @dout: Pointer to a string of bits to send out. The bits are 425 * held in a byte array and are sent MSB first. 426 * @din: Pointer to a string of bits that will be filled in. 427 * @flags: A bitwise combination of SPI_XFER_* flags. 428 * 429 * Returns: 0 on success, not -1 on failure 430 */ 431 int (*xfer)(struct udevice *dev, unsigned int bitlen, const void *dout, 432 void *din, unsigned long flags); 433 434 /** 435 * Set transfer speed. 436 * This sets a new speed to be applied for next spi_xfer(). 437 * @bus: The SPI bus 438 * @hz: The transfer speed 439 * @return 0 if OK, -ve on error 440 */ 441 int (*set_speed)(struct udevice *bus, uint hz); 442 443 /** 444 * Set the SPI mode/flags 445 * 446 * It is unclear if we want to set speed and mode together instead 447 * of separately. 448 * 449 * @bus: The SPI bus 450 * @mode: Requested SPI mode (SPI_... flags) 451 * @return 0 if OK, -ve on error 452 */ 453 int (*set_mode)(struct udevice *bus, uint mode); 454 455 /** 456 * Get information on a chip select 457 * 458 * This is only called when the SPI uclass does not know about a 459 * chip select, i.e. it has no attached device. It gives the driver 460 * a chance to allow activity on that chip select even so. 461 * 462 * @bus: The SPI bus 463 * @cs: The chip select (0..n-1) 464 * @info: Returns information about the chip select, if valid. 465 * On entry info->dev is NULL 466 * @return 0 if OK (and @info is set up), -ENODEV if the chip select 467 * is invalid, other -ve value on error 468 */ 469 int (*cs_info)(struct udevice *bus, uint cs, struct spi_cs_info *info); 470 }; 471 472 struct dm_spi_emul_ops { 473 /** 474 * SPI transfer 475 * 476 * This writes "bitlen" bits out the SPI MOSI port and simultaneously 477 * clocks "bitlen" bits in the SPI MISO port. That's just the way SPI 478 * works. Here the device is a slave. 479 * 480 * The source of the outgoing bits is the "dout" parameter and the 481 * destination of the input bits is the "din" parameter. Note that 482 * "dout" and "din" can point to the same memory location, in which 483 * case the input data overwrites the output data (since both are 484 * buffered by temporary variables, this is OK). 485 * 486 * spi_xfer() interface: 487 * @slave: The SPI slave which will be sending/receiving the data. 488 * @bitlen: How many bits to write and read. 489 * @dout: Pointer to a string of bits sent to the device. The 490 * bits are held in a byte array and are sent MSB first. 491 * @din: Pointer to a string of bits that will be sent back to 492 * the master. 493 * @flags: A bitwise combination of SPI_XFER_* flags. 494 * 495 * Returns: 0 on success, not -1 on failure 496 */ 497 int (*xfer)(struct udevice *slave, unsigned int bitlen, 498 const void *dout, void *din, unsigned long flags); 499 }; 500 501 /** 502 * spi_find_bus_and_cs() - Find 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. Neither device is activated by this function, 506 * although they may have been activated previously. 507 * 508 * @busnum: SPI bus number 509 * @cs: Chip select to look for 510 * @busp: Returns bus device 511 * @devp: Return slave device 512 * @return 0 if found, -ENODEV on error 513 */ 514 int spi_find_bus_and_cs(int busnum, int cs, struct udevice **busp, 515 struct udevice **devp); 516 517 /** 518 * spi_get_bus_and_cs() - Find and activate bus and slave devices by number 519 * 520 * Given a bus number and chip select, this finds the corresponding bus 521 * device and slave device. 522 * 523 * If no such slave exists, and drv_name is not NULL, then a new slave device 524 * is automatically bound on this chip select. 525 * 526 * Ths new slave device is probed ready for use with the given speed and mode. 527 * 528 * @busnum: SPI bus number 529 * @cs: Chip select to look for 530 * @speed: SPI speed to use for this slave 531 * @mode: SPI mode to use for this slave 532 * @drv_name: Name of driver to attach to this chip select 533 * @dev_name: Name of the new device thus created 534 * @busp: Returns bus device 535 * @devp: Return slave device 536 * @return 0 if found, -ve on error 537 */ 538 int spi_get_bus_and_cs(int busnum, int cs, int speed, int mode, 539 const char *drv_name, const char *dev_name, 540 struct udevice **busp, struct spi_slave **devp); 541 542 /** 543 * spi_chip_select() - Get the chip select for a slave 544 * 545 * @return the chip select this slave is attached to 546 */ 547 int spi_chip_select(struct udevice *slave); 548 549 /** 550 * spi_find_chip_select() - Find the slave attached to chip select 551 * 552 * @bus: SPI bus to search 553 * @cs: Chip select to look for 554 * @devp: Returns the slave device if found 555 * @return 0 if found, -ENODEV on error 556 */ 557 int spi_find_chip_select(struct udevice *bus, int cs, struct udevice **devp); 558 559 /** 560 * spi_slave_ofdata_to_platdata() - decode standard SPI platform data 561 * 562 * This decodes the speed and mode for a slave from a device tree node 563 * 564 * @blob: Device tree blob 565 * @node: Node offset to read from 566 * @plat: Place to put the decoded information 567 */ 568 int spi_slave_ofdata_to_platdata(struct udevice *dev, 569 struct dm_spi_slave_platdata *plat); 570 571 /** 572 * spi_cs_info() - Check information on a chip select 573 * 574 * This checks a particular chip select on a bus to see if it has a device 575 * attached, or is even valid. 576 * 577 * @bus: The SPI bus 578 * @cs: The chip select (0..n-1) 579 * @info: Returns information about the chip select, if valid 580 * @return 0 if OK (and @info is set up), -ENODEV if the chip select 581 * is invalid, other -ve value on error 582 */ 583 int spi_cs_info(struct udevice *bus, uint cs, struct spi_cs_info *info); 584 585 struct sandbox_state; 586 587 /** 588 * sandbox_spi_get_emul() - get an emulator for a SPI slave 589 * 590 * This provides a way to attach an emulated SPI device to a particular SPI 591 * slave, so that xfer() operations on the slave will be handled by the 592 * emulator. If a emulator already exists on that chip select it is returned. 593 * Otherwise one is created. 594 * 595 * @state: Sandbox state 596 * @bus: SPI bus requesting the emulator 597 * @slave: SPI slave device requesting the emulator 598 * @emuip: Returns pointer to emulator 599 * @return 0 if OK, -ve on error 600 */ 601 int sandbox_spi_get_emul(struct sandbox_state *state, 602 struct udevice *bus, struct udevice *slave, 603 struct udevice **emulp); 604 605 /** 606 * Claim the bus and prepare it for communication with a given slave. 607 * 608 * This must be called before doing any transfers with a SPI slave. It 609 * will enable and initialize any SPI hardware as necessary, and make 610 * sure that the SCK line is in the correct idle state. It is not 611 * allowed to claim the same bus for several slaves without releasing 612 * the bus in between. 613 * 614 * @dev: The SPI slave device 615 * 616 * Returns: 0 if the bus was claimed successfully, or a negative value 617 * if it wasn't. 618 */ 619 int dm_spi_claim_bus(struct udevice *dev); 620 621 /** 622 * Release the SPI bus 623 * 624 * This must be called once for every call to dm_spi_claim_bus() after 625 * all transfers have finished. It may disable any SPI hardware as 626 * appropriate. 627 * 628 * @slave: The SPI slave device 629 */ 630 void dm_spi_release_bus(struct udevice *dev); 631 632 /** 633 * SPI transfer 634 * 635 * This writes "bitlen" bits out the SPI MOSI port and simultaneously clocks 636 * "bitlen" bits in the SPI MISO port. That's just the way SPI works. 637 * 638 * The source of the outgoing bits is the "dout" parameter and the 639 * destination of the input bits is the "din" parameter. Note that "dout" 640 * and "din" can point to the same memory location, in which case the 641 * input data overwrites the output data (since both are buffered by 642 * temporary variables, this is OK). 643 * 644 * dm_spi_xfer() interface: 645 * @dev: The SPI slave device which will be sending/receiving the data. 646 * @bitlen: How many bits to write and read. 647 * @dout: Pointer to a string of bits to send out. The bits are 648 * held in a byte array and are sent MSB first. 649 * @din: Pointer to a string of bits that will be filled in. 650 * @flags: A bitwise combination of SPI_XFER_* flags. 651 * 652 * Returns: 0 on success, not 0 on failure 653 */ 654 int dm_spi_xfer(struct udevice *dev, unsigned int bitlen, 655 const void *dout, void *din, unsigned long flags); 656 657 /* Access the operations for a SPI device */ 658 #define spi_get_ops(dev) ((struct dm_spi_ops *)(dev)->driver->ops) 659 #define spi_emul_get_ops(dev) ((struct dm_spi_emul_ops *)(dev)->driver->ops) 660 #endif /* CONFIG_DM_SPI */ 661 662 #endif /* _SPI_H_ */ 663