1 /* SPDX-License-Identifier: GPL-2.0+ */ 2 /* 3 * Common SPI Interface: Controller-specific definitions 4 * 5 * (C) Copyright 2001 6 * Gerald Van Baren, Custom IDEAS, vanbaren@cideas.com. 7 */ 8 9 #ifndef _SPI_H_ 10 #define _SPI_H_ 11 12 #include <common.h> 13 14 /* SPI mode flags */ 15 #define SPI_CPHA BIT(0) /* clock phase */ 16 #define SPI_CPOL BIT(1) /* clock polarity */ 17 #define SPI_MODE_0 (0|0) /* (original MicroWire) */ 18 #define SPI_MODE_1 (0|SPI_CPHA) 19 #define SPI_MODE_2 (SPI_CPOL|0) 20 #define SPI_MODE_3 (SPI_CPOL|SPI_CPHA) 21 #define SPI_CS_HIGH BIT(2) /* CS active high */ 22 #define SPI_LSB_FIRST BIT(3) /* per-word bits-on-wire */ 23 #define SPI_3WIRE BIT(4) /* SI/SO signals shared */ 24 #define SPI_LOOP BIT(5) /* loopback mode */ 25 #define SPI_SLAVE BIT(6) /* slave mode */ 26 #define SPI_PREAMBLE BIT(7) /* Skip preamble bytes */ 27 #define SPI_TX_BYTE BIT(8) /* transmit with 1 wire byte */ 28 #define SPI_TX_DUAL BIT(9) /* transmit with 2 wires */ 29 #define SPI_TX_QUAD BIT(10) /* transmit with 4 wires */ 30 #define SPI_RX_SLOW BIT(11) /* receive with 1 wire slow */ 31 #define SPI_RX_DUAL BIT(12) /* receive with 2 wires */ 32 #define SPI_RX_QUAD BIT(13) /* receive with 4 wires */ 33 34 /* Header byte that marks the start of the message */ 35 #define SPI_PREAMBLE_END_BYTE 0xec 36 37 #define SPI_DEFAULT_WORDLEN 8 38 39 #ifdef CONFIG_DM_SPI 40 /* TODO(sjg@chromium.org): Remove this and use max_hz from struct spi_slave */ 41 struct dm_spi_bus { 42 uint max_hz; 43 }; 44 45 /** 46 * struct dm_spi_platdata - platform data for all SPI slaves 47 * 48 * This describes a SPI slave, a child device of the SPI bus. To obtain this 49 * struct from a spi_slave, use dev_get_parent_platdata(dev) or 50 * dev_get_parent_platdata(slave->dev). 51 * 52 * This data is immuatable. Each time the device is probed, @max_hz and @mode 53 * will be copied to struct spi_slave. 54 * 55 * @cs: Chip select number (0..n-1) 56 * @max_hz: Maximum bus speed that this slave can tolerate 57 * @mode: SPI mode to use for this device (see SPI mode flags) 58 */ 59 struct dm_spi_slave_platdata { 60 unsigned int cs; 61 uint max_hz; 62 uint mode; 63 }; 64 65 #endif /* CONFIG_DM_SPI */ 66 67 /** 68 * struct spi_slave - Representation of a SPI slave 69 * 70 * For driver model this is the per-child data used by the SPI bus. It can 71 * be accessed using dev_get_parent_priv() on the slave device. The SPI uclass 72 * sets uip per_child_auto_alloc_size to sizeof(struct spi_slave), and the 73 * driver should not override it. Two platform data fields (max_hz and mode) 74 * are copied into this structure to provide an initial value. This allows 75 * them to be changed, since we should never change platform data in drivers. 76 * 77 * If not using driver model, drivers are expected to extend this with 78 * controller-specific data. 79 * 80 * @dev: SPI slave device 81 * @max_hz: Maximum speed for this slave 82 * @speed: Current bus speed. This is 0 until the bus is first 83 * claimed. 84 * @bus: ID of the bus that the slave is attached to. For 85 * driver model this is the sequence number of the SPI 86 * bus (bus->seq) so does not need to be stored 87 * @cs: ID of the chip select connected to the slave. 88 * @mode: SPI mode to use for this slave (see SPI mode flags) 89 * @wordlen: Size of SPI word in number of bits 90 * @max_read_size: If non-zero, the maximum number of bytes which can 91 * be read at once. 92 * @max_write_size: If non-zero, the maximum number of bytes which can 93 * be written at once. 94 * @memory_map: Address of read-only SPI flash access. 95 * @flags: Indication of SPI flags. 96 */ 97 struct spi_slave { 98 #ifdef CONFIG_DM_SPI 99 struct udevice *dev; /* struct spi_slave is dev->parentdata */ 100 uint max_hz; 101 uint speed; 102 #else 103 unsigned int bus; 104 unsigned int cs; 105 #endif 106 uint mode; 107 unsigned int wordlen; 108 unsigned int max_read_size; 109 unsigned int max_write_size; 110 void *memory_map; 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 #ifdef CONFIG_DM_SPI 322 323 /** 324 * struct spi_cs_info - Information about a bus chip select 325 * 326 * @dev: Connected device, or NULL if none 327 */ 328 struct spi_cs_info { 329 struct udevice *dev; 330 }; 331 332 /** 333 * struct struct dm_spi_ops - Driver model SPI operations 334 * 335 * The uclass interface is implemented by all SPI devices which use 336 * driver model. 337 */ 338 struct dm_spi_ops { 339 /** 340 * Claim the bus and prepare it for communication. 341 * 342 * The device provided is the slave device. It's parent controller 343 * will be used to provide the communication. 344 * 345 * This must be called before doing any transfers with a SPI slave. It 346 * will enable and initialize any SPI hardware as necessary, and make 347 * sure that the SCK line is in the correct idle state. It is not 348 * allowed to claim the same bus for several slaves without releasing 349 * the bus in between. 350 * 351 * @dev: The SPI slave 352 * 353 * Returns: 0 if the bus was claimed successfully, or a negative value 354 * if it wasn't. 355 */ 356 int (*claim_bus)(struct udevice *dev); 357 358 /** 359 * Release the SPI bus 360 * 361 * This must be called once for every call to spi_claim_bus() after 362 * all transfers have finished. It may disable any SPI hardware as 363 * appropriate. 364 * 365 * @dev: The SPI slave 366 */ 367 int (*release_bus)(struct udevice *dev); 368 369 /** 370 * Set the word length for SPI transactions 371 * 372 * Set the word length (number of bits per word) for SPI transactions. 373 * 374 * @bus: The SPI slave 375 * @wordlen: The number of bits in a word 376 * 377 * Returns: 0 on success, -ve on failure. 378 */ 379 int (*set_wordlen)(struct udevice *dev, unsigned int wordlen); 380 381 /** 382 * SPI transfer 383 * 384 * This writes "bitlen" bits out the SPI MOSI port and simultaneously 385 * clocks "bitlen" bits in the SPI MISO port. That's just the way SPI 386 * works. 387 * 388 * The source of the outgoing bits is the "dout" parameter and the 389 * destination of the input bits is the "din" parameter. Note that 390 * "dout" and "din" can point to the same memory location, in which 391 * case the input data overwrites the output data (since both are 392 * buffered by temporary variables, this is OK). 393 * 394 * spi_xfer() interface: 395 * @dev: The slave device to communicate with 396 * @bitlen: How many bits to write and read. 397 * @dout: Pointer to a string of bits to send out. The bits are 398 * held in a byte array and are sent MSB first. 399 * @din: Pointer to a string of bits that will be filled in. 400 * @flags: A bitwise combination of SPI_XFER_* flags. 401 * 402 * Returns: 0 on success, not -1 on failure 403 */ 404 int (*xfer)(struct udevice *dev, unsigned int bitlen, const void *dout, 405 void *din, unsigned long flags); 406 407 /** 408 * Optimized handlers for SPI memory-like operations. 409 * 410 * Optimized/dedicated operations for interactions with SPI memory. This 411 * field is optional and should only be implemented if the controller 412 * has native support for memory like operations. 413 */ 414 const struct spi_controller_mem_ops *mem_ops; 415 416 /** 417 * Set transfer speed. 418 * This sets a new speed to be applied for next spi_xfer(). 419 * @bus: The SPI bus 420 * @hz: The transfer speed 421 * @return 0 if OK, -ve on error 422 */ 423 int (*set_speed)(struct udevice *bus, uint hz); 424 425 /** 426 * Set the SPI mode/flags 427 * 428 * It is unclear if we want to set speed and mode together instead 429 * of separately. 430 * 431 * @bus: The SPI bus 432 * @mode: Requested SPI mode (SPI_... flags) 433 * @return 0 if OK, -ve on error 434 */ 435 int (*set_mode)(struct udevice *bus, uint mode); 436 437 /** 438 * Get information on a chip select 439 * 440 * This is only called when the SPI uclass does not know about a 441 * chip select, i.e. it has no attached device. It gives the driver 442 * a chance to allow activity on that chip select even so. 443 * 444 * @bus: The SPI bus 445 * @cs: The chip select (0..n-1) 446 * @info: Returns information about the chip select, if valid. 447 * On entry info->dev is NULL 448 * @return 0 if OK (and @info is set up), -ENODEV if the chip select 449 * is invalid, other -ve value on error 450 */ 451 int (*cs_info)(struct udevice *bus, uint cs, struct spi_cs_info *info); 452 }; 453 454 struct dm_spi_emul_ops { 455 /** 456 * SPI transfer 457 * 458 * This writes "bitlen" bits out the SPI MOSI port and simultaneously 459 * clocks "bitlen" bits in the SPI MISO port. That's just the way SPI 460 * works. Here the device is a slave. 461 * 462 * The source of the outgoing bits is the "dout" parameter and the 463 * destination of the input bits is the "din" parameter. Note that 464 * "dout" and "din" can point to the same memory location, in which 465 * case the input data overwrites the output data (since both are 466 * buffered by temporary variables, this is OK). 467 * 468 * spi_xfer() interface: 469 * @slave: The SPI slave which will be sending/receiving the data. 470 * @bitlen: How many bits to write and read. 471 * @dout: Pointer to a string of bits sent to the device. The 472 * bits are held in a byte array and are sent MSB first. 473 * @din: Pointer to a string of bits that will be sent back to 474 * the master. 475 * @flags: A bitwise combination of SPI_XFER_* flags. 476 * 477 * Returns: 0 on success, not -1 on failure 478 */ 479 int (*xfer)(struct udevice *slave, unsigned int bitlen, 480 const void *dout, void *din, unsigned long flags); 481 }; 482 483 /** 484 * spi_find_bus_and_cs() - Find bus and slave devices by number 485 * 486 * Given a bus number and chip select, this finds the corresponding bus 487 * device and slave device. Neither device is activated by this function, 488 * although they may have been activated previously. 489 * 490 * @busnum: SPI bus number 491 * @cs: Chip select to look for 492 * @busp: Returns bus device 493 * @devp: Return slave device 494 * @return 0 if found, -ENODEV on error 495 */ 496 int spi_find_bus_and_cs(int busnum, int cs, struct udevice **busp, 497 struct udevice **devp); 498 499 /** 500 * spi_get_bus_and_cs() - Find and activate bus and slave devices by number 501 * 502 * Given a bus number and chip select, this finds the corresponding bus 503 * device and slave device. 504 * 505 * If no such slave exists, and drv_name is not NULL, then a new slave device 506 * is automatically bound on this chip select. 507 * 508 * Ths new slave device is probed ready for use with the given speed and mode. 509 * 510 * @busnum: SPI bus number 511 * @cs: Chip select to look for 512 * @speed: SPI speed to use for this slave 513 * @mode: SPI mode to use for this slave 514 * @drv_name: Name of driver to attach to this chip select 515 * @dev_name: Name of the new device thus created 516 * @busp: Returns bus device 517 * @devp: Return slave device 518 * @return 0 if found, -ve on error 519 */ 520 int spi_get_bus_and_cs(int busnum, int cs, int speed, int mode, 521 const char *drv_name, const char *dev_name, 522 struct udevice **busp, struct spi_slave **devp); 523 524 /** 525 * spi_chip_select() - Get the chip select for a slave 526 * 527 * @return the chip select this slave is attached to 528 */ 529 int spi_chip_select(struct udevice *slave); 530 531 /** 532 * spi_find_chip_select() - Find the slave attached to chip select 533 * 534 * @bus: SPI bus to search 535 * @cs: Chip select to look for 536 * @devp: Returns the slave device if found 537 * @return 0 if found, -ENODEV on error 538 */ 539 int spi_find_chip_select(struct udevice *bus, int cs, struct udevice **devp); 540 541 /** 542 * spi_slave_ofdata_to_platdata() - decode standard SPI platform data 543 * 544 * This decodes the speed and mode for a slave from a device tree node 545 * 546 * @blob: Device tree blob 547 * @node: Node offset to read from 548 * @plat: Place to put the decoded information 549 */ 550 int spi_slave_ofdata_to_platdata(struct udevice *dev, 551 struct dm_spi_slave_platdata *plat); 552 553 /** 554 * spi_cs_info() - Check information on a chip select 555 * 556 * This checks a particular chip select on a bus to see if it has a device 557 * attached, or is even valid. 558 * 559 * @bus: The SPI bus 560 * @cs: The chip select (0..n-1) 561 * @info: Returns information about the chip select, if valid 562 * @return 0 if OK (and @info is set up), -ENODEV if the chip select 563 * is invalid, other -ve value on error 564 */ 565 int spi_cs_info(struct udevice *bus, uint cs, struct spi_cs_info *info); 566 567 struct sandbox_state; 568 569 /** 570 * sandbox_spi_get_emul() - get an emulator for a SPI slave 571 * 572 * This provides a way to attach an emulated SPI device to a particular SPI 573 * slave, so that xfer() operations on the slave will be handled by the 574 * emulator. If a emulator already exists on that chip select it is returned. 575 * Otherwise one is created. 576 * 577 * @state: Sandbox state 578 * @bus: SPI bus requesting the emulator 579 * @slave: SPI slave device requesting the emulator 580 * @emuip: Returns pointer to emulator 581 * @return 0 if OK, -ve on error 582 */ 583 int sandbox_spi_get_emul(struct sandbox_state *state, 584 struct udevice *bus, struct udevice *slave, 585 struct udevice **emulp); 586 587 /** 588 * Claim the bus and prepare it for communication with a given slave. 589 * 590 * This must be called before doing any transfers with a SPI slave. It 591 * will enable and initialize any SPI hardware as necessary, and make 592 * sure that the SCK line is in the correct idle state. It is not 593 * allowed to claim the same bus for several slaves without releasing 594 * the bus in between. 595 * 596 * @dev: The SPI slave device 597 * 598 * Returns: 0 if the bus was claimed successfully, or a negative value 599 * if it wasn't. 600 */ 601 int dm_spi_claim_bus(struct udevice *dev); 602 603 /** 604 * Release the SPI bus 605 * 606 * This must be called once for every call to dm_spi_claim_bus() after 607 * all transfers have finished. It may disable any SPI hardware as 608 * appropriate. 609 * 610 * @slave: The SPI slave device 611 */ 612 void dm_spi_release_bus(struct udevice *dev); 613 614 /** 615 * SPI transfer 616 * 617 * This writes "bitlen" bits out the SPI MOSI port and simultaneously clocks 618 * "bitlen" bits in the SPI MISO port. That's just the way SPI works. 619 * 620 * The source of the outgoing bits is the "dout" parameter and the 621 * destination of the input bits is the "din" parameter. Note that "dout" 622 * and "din" can point to the same memory location, in which case the 623 * input data overwrites the output data (since both are buffered by 624 * temporary variables, this is OK). 625 * 626 * dm_spi_xfer() interface: 627 * @dev: The SPI slave device which will be sending/receiving the data. 628 * @bitlen: How many bits to write and read. 629 * @dout: Pointer to a string of bits to send out. The bits are 630 * held in a byte array and are sent MSB first. 631 * @din: Pointer to a string of bits that will be filled in. 632 * @flags: A bitwise combination of SPI_XFER_* flags. 633 * 634 * Returns: 0 on success, not 0 on failure 635 */ 636 int dm_spi_xfer(struct udevice *dev, unsigned int bitlen, 637 const void *dout, void *din, unsigned long flags); 638 639 /* Access the operations for a SPI device */ 640 #define spi_get_ops(dev) ((struct dm_spi_ops *)(dev)->driver->ops) 641 #define spi_emul_get_ops(dev) ((struct dm_spi_emul_ops *)(dev)->driver->ops) 642 #endif /* CONFIG_DM_SPI */ 643 644 #endif /* _SPI_H_ */ 645