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