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 * spi_do_alloc_slave - Allocate a new SPI slave (internal) 122 * 123 * Allocate and zero all fields in the spi slave, and set the bus/chip 124 * select. Use the helper macro spi_alloc_slave() to call this. 125 * 126 * @offset: Offset of struct spi_slave within slave structure. 127 * @size: Size of slave structure. 128 * @bus: Bus ID of the slave chip. 129 * @cs: Chip select ID of the slave chip on the specified bus. 130 */ 131 void *spi_do_alloc_slave(int offset, int size, unsigned int bus, 132 unsigned int cs); 133 134 /** 135 * spi_alloc_slave - Allocate a new SPI slave 136 * 137 * Allocate and zero all fields in the spi slave, and set the bus/chip 138 * select. 139 * 140 * @_struct: Name of structure to allocate (e.g. struct tegra_spi). 141 * This structure must contain a member 'struct spi_slave *slave'. 142 * @bus: Bus ID of the slave chip. 143 * @cs: Chip select ID of the slave chip on the specified bus. 144 */ 145 #define spi_alloc_slave(_struct, bus, cs) \ 146 spi_do_alloc_slave(offsetof(_struct, slave), \ 147 sizeof(_struct), bus, cs) 148 149 /** 150 * spi_alloc_slave_base - Allocate a new SPI slave with no private data 151 * 152 * Allocate and zero all fields in the spi slave, and set the bus/chip 153 * select. 154 * 155 * @bus: Bus ID of the slave chip. 156 * @cs: Chip select ID of the slave chip on the specified bus. 157 */ 158 #define spi_alloc_slave_base(bus, cs) \ 159 spi_do_alloc_slave(0, sizeof(struct spi_slave), bus, cs) 160 161 /** 162 * Set up communications parameters for a SPI slave. 163 * 164 * This must be called once for each slave. Note that this function 165 * usually doesn't touch any actual hardware, it only initializes the 166 * contents of spi_slave so that the hardware can be easily 167 * initialized later. 168 * 169 * @bus: Bus ID of the slave chip. 170 * @cs: Chip select ID of the slave chip on the specified bus. 171 * @max_hz: Maximum SCK rate in Hz. 172 * @mode: Clock polarity, clock phase and other parameters. 173 * 174 * Returns: A spi_slave reference that can be used in subsequent SPI 175 * calls, or NULL if one or more of the parameters are not supported. 176 */ 177 struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs, 178 unsigned int max_hz, unsigned int mode); 179 180 /** 181 * Free any memory associated with a SPI slave. 182 * 183 * @slave: The SPI slave 184 */ 185 void spi_free_slave(struct spi_slave *slave); 186 187 /** 188 * Claim the bus and prepare it for communication with a given slave. 189 * 190 * This must be called before doing any transfers with a SPI slave. It 191 * will enable and initialize any SPI hardware as necessary, and make 192 * sure that the SCK line is in the correct idle state. It is not 193 * allowed to claim the same bus for several slaves without releasing 194 * the bus in between. 195 * 196 * @slave: The SPI slave 197 * 198 * Returns: 0 if the bus was claimed successfully, or a negative value 199 * if it wasn't. 200 */ 201 int spi_claim_bus(struct spi_slave *slave); 202 203 /** 204 * Release the SPI bus 205 * 206 * This must be called once for every call to spi_claim_bus() after 207 * all transfers have finished. It may disable any SPI hardware as 208 * appropriate. 209 * 210 * @slave: The SPI slave 211 */ 212 void spi_release_bus(struct spi_slave *slave); 213 214 /** 215 * Set the word length for SPI transactions 216 * 217 * Set the word length (number of bits per word) for SPI transactions. 218 * 219 * @slave: The SPI slave 220 * @wordlen: The number of bits in a word 221 * 222 * Returns: 0 on success, -1 on failure. 223 */ 224 int spi_set_wordlen(struct spi_slave *slave, unsigned int wordlen); 225 226 /** 227 * SPI transfer 228 * 229 * This writes "bitlen" bits out the SPI MOSI port and simultaneously clocks 230 * "bitlen" bits in the SPI MISO port. That's just the way SPI works. 231 * 232 * The source of the outgoing bits is the "dout" parameter and the 233 * destination of the input bits is the "din" parameter. Note that "dout" 234 * and "din" can point to the same memory location, in which case the 235 * input data overwrites the output data (since both are buffered by 236 * temporary variables, this is OK). 237 * 238 * spi_xfer() interface: 239 * @slave: The SPI slave which will be sending/receiving the data. 240 * @bitlen: How many bits to write and read. 241 * @dout: Pointer to a string of bits to send out. The bits are 242 * held in a byte array and are sent MSB first. 243 * @din: Pointer to a string of bits that will be filled in. 244 * @flags: A bitwise combination of SPI_XFER_* flags. 245 * 246 * Returns: 0 on success, not 0 on failure 247 */ 248 int spi_xfer(struct spi_slave *slave, unsigned int bitlen, const void *dout, 249 void *din, unsigned long flags); 250 251 /* Copy memory mapped data */ 252 void spi_flash_copy_mmap(void *data, void *offset, size_t len); 253 254 /** 255 * Determine if a SPI chipselect is valid. 256 * This function is provided by the board if the low-level SPI driver 257 * needs it to determine if a given chipselect is actually valid. 258 * 259 * Returns: 1 if bus:cs identifies a valid chip on this board, 0 260 * otherwise. 261 */ 262 int spi_cs_is_valid(unsigned int bus, unsigned int cs); 263 264 #ifndef CONFIG_DM_SPI 265 /** 266 * Activate a SPI chipselect. 267 * This function is provided by the board code when using a driver 268 * that can't control its chipselects automatically (e.g. 269 * common/soft_spi.c). When called, it should activate the chip select 270 * to the device identified by "slave". 271 */ 272 void spi_cs_activate(struct spi_slave *slave); 273 274 /** 275 * Deactivate 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 deactivate the chip 279 * select to the device identified by "slave". 280 */ 281 void spi_cs_deactivate(struct spi_slave *slave); 282 283 /** 284 * Set transfer speed. 285 * This sets a new speed to be applied for next spi_xfer(). 286 * @slave: The SPI slave 287 * @hz: The transfer speed 288 */ 289 void spi_set_speed(struct spi_slave *slave, uint hz); 290 #endif 291 292 /** 293 * Write 8 bits, then read 8 bits. 294 * @slave: The SPI slave we're communicating with 295 * @byte: Byte to be written 296 * 297 * Returns: The value that was read, or a negative value on error. 298 * 299 * TODO: This function probably shouldn't be inlined. 300 */ 301 static inline int spi_w8r8(struct spi_slave *slave, unsigned char byte) 302 { 303 unsigned char dout[2]; 304 unsigned char din[2]; 305 int ret; 306 307 dout[0] = byte; 308 dout[1] = 0; 309 310 ret = spi_xfer(slave, 16, dout, din, SPI_XFER_BEGIN | SPI_XFER_END); 311 return ret < 0 ? ret : din[1]; 312 } 313 314 #ifdef CONFIG_DM_SPI 315 316 /** 317 * struct spi_cs_info - Information about a bus chip select 318 * 319 * @dev: Connected device, or NULL if none 320 */ 321 struct spi_cs_info { 322 struct udevice *dev; 323 }; 324 325 /** 326 * struct struct dm_spi_ops - Driver model SPI operations 327 * 328 * The uclass interface is implemented by all SPI devices which use 329 * driver model. 330 */ 331 struct dm_spi_ops { 332 /** 333 * Claim the bus and prepare it for communication. 334 * 335 * The device provided is the slave device. It's parent controller 336 * will be used to provide the communication. 337 * 338 * This must be called before doing any transfers with a SPI slave. It 339 * will enable and initialize any SPI hardware as necessary, and make 340 * sure that the SCK line is in the correct idle state. It is not 341 * allowed to claim the same bus for several slaves without releasing 342 * the bus in between. 343 * 344 * @dev: The SPI slave 345 * 346 * Returns: 0 if the bus was claimed successfully, or a negative value 347 * if it wasn't. 348 */ 349 int (*claim_bus)(struct udevice *dev); 350 351 /** 352 * Release the SPI bus 353 * 354 * This must be called once for every call to spi_claim_bus() after 355 * all transfers have finished. It may disable any SPI hardware as 356 * appropriate. 357 * 358 * @dev: The SPI slave 359 */ 360 int (*release_bus)(struct udevice *dev); 361 362 /** 363 * Set the word length for SPI transactions 364 * 365 * Set the word length (number of bits per word) for SPI transactions. 366 * 367 * @bus: The SPI slave 368 * @wordlen: The number of bits in a word 369 * 370 * Returns: 0 on success, -ve on failure. 371 */ 372 int (*set_wordlen)(struct udevice *dev, unsigned int wordlen); 373 374 /** 375 * SPI transfer 376 * 377 * This writes "bitlen" bits out the SPI MOSI port and simultaneously 378 * clocks "bitlen" bits in the SPI MISO port. That's just the way SPI 379 * works. 380 * 381 * The source of the outgoing bits is the "dout" parameter and the 382 * destination of the input bits is the "din" parameter. Note that 383 * "dout" and "din" can point to the same memory location, in which 384 * case the input data overwrites the output data (since both are 385 * buffered by temporary variables, this is OK). 386 * 387 * spi_xfer() interface: 388 * @dev: The slave device to communicate with 389 * @bitlen: How many bits to write and read. 390 * @dout: Pointer to a string of bits to send out. The bits are 391 * held in a byte array and are sent MSB first. 392 * @din: Pointer to a string of bits that will be filled in. 393 * @flags: A bitwise combination of SPI_XFER_* flags. 394 * 395 * Returns: 0 on success, not -1 on failure 396 */ 397 int (*xfer)(struct udevice *dev, unsigned int bitlen, const void *dout, 398 void *din, unsigned long flags); 399 400 /** 401 * Optimized handlers for SPI memory-like operations. 402 * 403 * Optimized/dedicated operations for interactions with SPI memory. This 404 * field is optional and should only be implemented if the controller 405 * has native support for memory like operations. 406 */ 407 const struct spi_controller_mem_ops *mem_ops; 408 409 /** 410 * Set transfer speed. 411 * This sets a new speed to be applied for next spi_xfer(). 412 * @bus: The SPI bus 413 * @hz: The transfer speed 414 * @return 0 if OK, -ve on error 415 */ 416 int (*set_speed)(struct udevice *bus, uint hz); 417 418 /** 419 * Set the SPI mode/flags 420 * 421 * It is unclear if we want to set speed and mode together instead 422 * of separately. 423 * 424 * @bus: The SPI bus 425 * @mode: Requested SPI mode (SPI_... flags) 426 * @return 0 if OK, -ve on error 427 */ 428 int (*set_mode)(struct udevice *bus, uint mode); 429 430 /** 431 * Get information on a chip select 432 * 433 * This is only called when the SPI uclass does not know about a 434 * chip select, i.e. it has no attached device. It gives the driver 435 * a chance to allow activity on that chip select even so. 436 * 437 * @bus: The SPI bus 438 * @cs: The chip select (0..n-1) 439 * @info: Returns information about the chip select, if valid. 440 * On entry info->dev is NULL 441 * @return 0 if OK (and @info is set up), -ENODEV if the chip select 442 * is invalid, other -ve value on error 443 */ 444 int (*cs_info)(struct udevice *bus, uint cs, struct spi_cs_info *info); 445 }; 446 447 struct dm_spi_emul_ops { 448 /** 449 * SPI transfer 450 * 451 * This writes "bitlen" bits out the SPI MOSI port and simultaneously 452 * clocks "bitlen" bits in the SPI MISO port. That's just the way SPI 453 * works. Here the device is a slave. 454 * 455 * The source of the outgoing bits is the "dout" parameter and the 456 * destination of the input bits is the "din" parameter. Note that 457 * "dout" and "din" can point to the same memory location, in which 458 * case the input data overwrites the output data (since both are 459 * buffered by temporary variables, this is OK). 460 * 461 * spi_xfer() interface: 462 * @slave: The SPI slave which will be sending/receiving the data. 463 * @bitlen: How many bits to write and read. 464 * @dout: Pointer to a string of bits sent to the device. The 465 * bits are held in a byte array and are sent MSB first. 466 * @din: Pointer to a string of bits that will be sent back to 467 * the master. 468 * @flags: A bitwise combination of SPI_XFER_* flags. 469 * 470 * Returns: 0 on success, not -1 on failure 471 */ 472 int (*xfer)(struct udevice *slave, unsigned int bitlen, 473 const void *dout, void *din, unsigned long flags); 474 }; 475 476 /** 477 * spi_find_bus_and_cs() - Find bus and slave devices by number 478 * 479 * Given a bus number and chip select, this finds the corresponding bus 480 * device and slave device. Neither device is activated by this function, 481 * although they may have been activated previously. 482 * 483 * @busnum: SPI bus number 484 * @cs: Chip select to look for 485 * @busp: Returns bus device 486 * @devp: Return slave device 487 * @return 0 if found, -ENODEV on error 488 */ 489 int spi_find_bus_and_cs(int busnum, int cs, struct udevice **busp, 490 struct udevice **devp); 491 492 /** 493 * spi_get_bus_and_cs() - Find and activate bus and slave devices by number 494 * 495 * Given a bus number and chip select, this finds the corresponding bus 496 * device and slave device. 497 * 498 * If no such slave exists, and drv_name is not NULL, then a new slave device 499 * is automatically bound on this chip select. 500 * 501 * Ths new slave device is probed ready for use with the given speed and mode. 502 * 503 * @busnum: SPI bus number 504 * @cs: Chip select to look for 505 * @speed: SPI speed to use for this slave 506 * @mode: SPI mode to use for this slave 507 * @drv_name: Name of driver to attach to this chip select 508 * @dev_name: Name of the new device thus created 509 * @busp: Returns bus device 510 * @devp: Return slave device 511 * @return 0 if found, -ve on error 512 */ 513 int spi_get_bus_and_cs(int busnum, int cs, int speed, int mode, 514 const char *drv_name, const char *dev_name, 515 struct udevice **busp, struct spi_slave **devp); 516 517 /** 518 * spi_chip_select() - Get the chip select for a slave 519 * 520 * @return the chip select this slave is attached to 521 */ 522 int spi_chip_select(struct udevice *slave); 523 524 /** 525 * spi_find_chip_select() - Find the slave attached to chip select 526 * 527 * @bus: SPI bus to search 528 * @cs: Chip select to look for 529 * @devp: Returns the slave device if found 530 * @return 0 if found, -ENODEV on error 531 */ 532 int spi_find_chip_select(struct udevice *bus, int cs, struct udevice **devp); 533 534 /** 535 * spi_slave_ofdata_to_platdata() - decode standard SPI platform data 536 * 537 * This decodes the speed and mode for a slave from a device tree node 538 * 539 * @blob: Device tree blob 540 * @node: Node offset to read from 541 * @plat: Place to put the decoded information 542 */ 543 int spi_slave_ofdata_to_platdata(struct udevice *dev, 544 struct dm_spi_slave_platdata *plat); 545 546 /** 547 * spi_cs_info() - Check information on a chip select 548 * 549 * This checks a particular chip select on a bus to see if it has a device 550 * attached, or is even valid. 551 * 552 * @bus: The SPI bus 553 * @cs: The chip select (0..n-1) 554 * @info: Returns information about the chip select, if valid 555 * @return 0 if OK (and @info is set up), -ENODEV if the chip select 556 * is invalid, other -ve value on error 557 */ 558 int spi_cs_info(struct udevice *bus, uint cs, struct spi_cs_info *info); 559 560 struct sandbox_state; 561 562 /** 563 * sandbox_spi_get_emul() - get an emulator for a SPI slave 564 * 565 * This provides a way to attach an emulated SPI device to a particular SPI 566 * slave, so that xfer() operations on the slave will be handled by the 567 * emulator. If a emulator already exists on that chip select it is returned. 568 * Otherwise one is created. 569 * 570 * @state: Sandbox state 571 * @bus: SPI bus requesting the emulator 572 * @slave: SPI slave device requesting the emulator 573 * @emuip: Returns pointer to emulator 574 * @return 0 if OK, -ve on error 575 */ 576 int sandbox_spi_get_emul(struct sandbox_state *state, 577 struct udevice *bus, struct udevice *slave, 578 struct udevice **emulp); 579 580 /** 581 * Claim the bus and prepare it for communication with a given slave. 582 * 583 * This must be called before doing any transfers with a SPI slave. It 584 * will enable and initialize any SPI hardware as necessary, and make 585 * sure that the SCK line is in the correct idle state. It is not 586 * allowed to claim the same bus for several slaves without releasing 587 * the bus in between. 588 * 589 * @dev: The SPI slave device 590 * 591 * Returns: 0 if the bus was claimed successfully, or a negative value 592 * if it wasn't. 593 */ 594 int dm_spi_claim_bus(struct udevice *dev); 595 596 /** 597 * Release the SPI bus 598 * 599 * This must be called once for every call to dm_spi_claim_bus() after 600 * all transfers have finished. It may disable any SPI hardware as 601 * appropriate. 602 * 603 * @slave: The SPI slave device 604 */ 605 void dm_spi_release_bus(struct udevice *dev); 606 607 /** 608 * SPI transfer 609 * 610 * This writes "bitlen" bits out the SPI MOSI port and simultaneously clocks 611 * "bitlen" bits in the SPI MISO port. That's just the way SPI works. 612 * 613 * The source of the outgoing bits is the "dout" parameter and the 614 * destination of the input bits is the "din" parameter. Note that "dout" 615 * and "din" can point to the same memory location, in which case the 616 * input data overwrites the output data (since both are buffered by 617 * temporary variables, this is OK). 618 * 619 * dm_spi_xfer() interface: 620 * @dev: The SPI slave device which will be sending/receiving the data. 621 * @bitlen: How many bits to write and read. 622 * @dout: Pointer to a string of bits to send out. The bits are 623 * held in a byte array and are sent MSB first. 624 * @din: Pointer to a string of bits that will be filled in. 625 * @flags: A bitwise combination of SPI_XFER_* flags. 626 * 627 * Returns: 0 on success, not 0 on failure 628 */ 629 int dm_spi_xfer(struct udevice *dev, unsigned int bitlen, 630 const void *dout, void *din, unsigned long flags); 631 632 /* Access the operations for a SPI device */ 633 #define spi_get_ops(dev) ((struct dm_spi_ops *)(dev)->driver->ops) 634 #define spi_emul_get_ops(dev) ((struct dm_spi_emul_ops *)(dev)->driver->ops) 635 #endif /* CONFIG_DM_SPI */ 636 637 #endif /* _SPI_H_ */ 638