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 30 /* SPI mode_rx flags */ 31 #define SPI_RX_SLOW BIT(0) /* receive with 1 wire slow */ 32 #define SPI_RX_FAST BIT(1) /* receive with 1 wire fast */ 33 #define SPI_RX_DUAL BIT(2) /* receive with 2 wires */ 34 #define SPI_RX_QUAD BIT(3) /* receive with 4 wires */ 35 36 /* SPI bus connection options - see enum spi_dual_flash */ 37 #define SPI_CONN_DUAL_SHARED (1 << 0) 38 #define SPI_CONN_DUAL_SEPARATED (1 << 1) 39 40 /* Header byte that marks the start of the message */ 41 #define SPI_PREAMBLE_END_BYTE 0xec 42 43 #define SPI_DEFAULT_WORDLEN 8 44 45 #ifdef CONFIG_DM_SPI 46 /* TODO(sjg@chromium.org): Remove this and use max_hz from struct spi_slave */ 47 struct dm_spi_bus { 48 uint max_hz; 49 }; 50 51 /** 52 * struct dm_spi_platdata - platform data for all SPI slaves 53 * 54 * This describes a SPI slave, a child device of the SPI bus. To obtain this 55 * struct from a spi_slave, use dev_get_parent_platdata(dev) or 56 * dev_get_parent_platdata(slave->dev). 57 * 58 * This data is immuatable. Each time the device is probed, @max_hz and @mode 59 * will be copied to struct spi_slave. 60 * 61 * @cs: Chip select number (0..n-1) 62 * @max_hz: Maximum bus speed that this slave can tolerate 63 * @mode: SPI mode to use for this device (see SPI mode flags) 64 */ 65 struct dm_spi_slave_platdata { 66 unsigned int cs; 67 uint max_hz; 68 uint mode; 69 }; 70 71 #endif /* CONFIG_DM_SPI */ 72 73 /** 74 * struct spi_slave - Representation of a SPI slave 75 * 76 * For driver model this is the per-child data used by the SPI bus. It can 77 * be accessed using dev_get_parent_priv() on the slave device. The SPI uclass 78 * sets uip per_child_auto_alloc_size to sizeof(struct spi_slave), and the 79 * driver should not override it. Two platform data fields (max_hz and mode) 80 * are copied into this structure to provide an initial value. This allows 81 * them to be changed, since we should never change platform data in drivers. 82 * 83 * If not using driver model, drivers are expected to extend this with 84 * controller-specific data. 85 * 86 * @dev: SPI slave device 87 * @max_hz: Maximum speed for this slave 88 * @speed: Current bus speed. This is 0 until the bus is first 89 * claimed. 90 * @bus: ID of the bus that the slave is attached to. For 91 * driver model this is the sequence number of the SPI 92 * bus (bus->seq) so does not need to be stored 93 * @cs: ID of the chip select connected to the slave. 94 * @mode: SPI mode to use for this slave (see SPI mode flags) 95 * @mode_rx: SPI RX mode to use for this slave (see SPI mode_rx flags) 96 * @wordlen: Size of SPI word in number of bits 97 * @max_write_size: If non-zero, the maximum number of bytes which can 98 * be written at once, excluding command bytes. 99 * @memory_map: Address of read-only SPI flash access. 100 * @option: Varies SPI bus options - separate, shared bus. 101 * @flags: Indication of SPI flags. 102 */ 103 struct spi_slave { 104 #ifdef CONFIG_DM_SPI 105 struct udevice *dev; /* struct spi_slave is dev->parentdata */ 106 uint max_hz; 107 uint speed; 108 #else 109 unsigned int bus; 110 unsigned int cs; 111 #endif 112 uint mode; 113 u8 mode_rx; 114 unsigned int wordlen; 115 unsigned int max_write_size; 116 void *memory_map; 117 u8 option; 118 119 u8 flags; 120 #define SPI_XFER_BEGIN BIT(0) /* Assert CS before transfer */ 121 #define SPI_XFER_END BIT(1) /* Deassert CS after transfer */ 122 #define SPI_XFER_ONCE (SPI_XFER_BEGIN | SPI_XFER_END) 123 #define SPI_XFER_MMAP BIT(2) /* Memory Mapped start */ 124 #define SPI_XFER_MMAP_END BIT(3) /* Memory Mapped End */ 125 #define SPI_XFER_U_PAGE BIT(4) 126 }; 127 128 /** 129 * Initialization, must be called once on start up. 130 * 131 * TODO: I don't think we really need this. 132 */ 133 void spi_init(void); 134 135 /** 136 * spi_do_alloc_slave - Allocate a new SPI slave (internal) 137 * 138 * Allocate and zero all fields in the spi slave, and set the bus/chip 139 * select. Use the helper macro spi_alloc_slave() to call this. 140 * 141 * @offset: Offset of struct spi_slave within slave structure. 142 * @size: Size of slave structure. 143 * @bus: Bus ID of the slave chip. 144 * @cs: Chip select ID of the slave chip on the specified bus. 145 */ 146 void *spi_do_alloc_slave(int offset, int size, unsigned int bus, 147 unsigned int cs); 148 149 /** 150 * spi_alloc_slave - Allocate a new SPI slave 151 * 152 * Allocate and zero all fields in the spi slave, and set the bus/chip 153 * select. 154 * 155 * @_struct: Name of structure to allocate (e.g. struct tegra_spi). 156 * This structure must contain a member 'struct spi_slave *slave'. 157 * @bus: Bus ID of the slave chip. 158 * @cs: Chip select ID of the slave chip on the specified bus. 159 */ 160 #define spi_alloc_slave(_struct, bus, cs) \ 161 spi_do_alloc_slave(offsetof(_struct, slave), \ 162 sizeof(_struct), bus, cs) 163 164 /** 165 * spi_alloc_slave_base - Allocate a new SPI slave with no private data 166 * 167 * Allocate and zero all fields in the spi slave, and set the bus/chip 168 * select. 169 * 170 * @bus: Bus ID of the slave chip. 171 * @cs: Chip select ID of the slave chip on the specified bus. 172 */ 173 #define spi_alloc_slave_base(bus, cs) \ 174 spi_do_alloc_slave(0, sizeof(struct spi_slave), bus, cs) 175 176 /** 177 * Set up communications parameters for a SPI slave. 178 * 179 * This must be called once for each slave. Note that this function 180 * usually doesn't touch any actual hardware, it only initializes the 181 * contents of spi_slave so that the hardware can be easily 182 * initialized later. 183 * 184 * @bus: Bus ID of the slave chip. 185 * @cs: Chip select ID of the slave chip on the specified bus. 186 * @max_hz: Maximum SCK rate in Hz. 187 * @mode: Clock polarity, clock phase and other parameters. 188 * 189 * Returns: A spi_slave reference that can be used in subsequent SPI 190 * calls, or NULL if one or more of the parameters are not supported. 191 */ 192 struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs, 193 unsigned int max_hz, unsigned int mode); 194 195 /** 196 * Free any memory associated with a SPI slave. 197 * 198 * @slave: The SPI slave 199 */ 200 void spi_free_slave(struct spi_slave *slave); 201 202 /** 203 * Claim the bus and prepare it for communication with a given slave. 204 * 205 * This must be called before doing any transfers with a SPI slave. It 206 * will enable and initialize any SPI hardware as necessary, and make 207 * sure that the SCK line is in the correct idle state. It is not 208 * allowed to claim the same bus for several slaves without releasing 209 * the bus in between. 210 * 211 * @slave: The SPI slave 212 * 213 * Returns: 0 if the bus was claimed successfully, or a negative value 214 * if it wasn't. 215 */ 216 int spi_claim_bus(struct spi_slave *slave); 217 218 /** 219 * Release the SPI bus 220 * 221 * This must be called once for every call to spi_claim_bus() after 222 * all transfers have finished. It may disable any SPI hardware as 223 * appropriate. 224 * 225 * @slave: The SPI slave 226 */ 227 void spi_release_bus(struct spi_slave *slave); 228 229 /** 230 * Set the word length for SPI transactions 231 * 232 * Set the word length (number of bits per word) for SPI transactions. 233 * 234 * @slave: The SPI slave 235 * @wordlen: The number of bits in a word 236 * 237 * Returns: 0 on success, -1 on failure. 238 */ 239 int spi_set_wordlen(struct spi_slave *slave, unsigned int wordlen); 240 241 /** 242 * SPI transfer 243 * 244 * This writes "bitlen" bits out the SPI MOSI port and simultaneously clocks 245 * "bitlen" bits in the SPI MISO port. That's just the way SPI works. 246 * 247 * The source of the outgoing bits is the "dout" parameter and the 248 * destination of the input bits is the "din" parameter. Note that "dout" 249 * and "din" can point to the same memory location, in which case the 250 * input data overwrites the output data (since both are buffered by 251 * temporary variables, this is OK). 252 * 253 * spi_xfer() interface: 254 * @slave: The SPI slave which will be sending/receiving the data. 255 * @bitlen: How many bits to write and read. 256 * @dout: Pointer to a string of bits to send out. The bits are 257 * held in a byte array and are sent MSB first. 258 * @din: Pointer to a string of bits that will be filled in. 259 * @flags: A bitwise combination of SPI_XFER_* flags. 260 * 261 * Returns: 0 on success, not 0 on failure 262 */ 263 int spi_xfer(struct spi_slave *slave, unsigned int bitlen, const void *dout, 264 void *din, unsigned long flags); 265 266 /* Copy memory mapped data */ 267 void spi_flash_copy_mmap(void *data, void *offset, size_t len); 268 269 /** 270 * Determine if a SPI chipselect is valid. 271 * This function is provided by the board if the low-level SPI driver 272 * needs it to determine if a given chipselect is actually valid. 273 * 274 * Returns: 1 if bus:cs identifies a valid chip on this board, 0 275 * otherwise. 276 */ 277 int spi_cs_is_valid(unsigned int bus, unsigned int cs); 278 279 #ifndef CONFIG_DM_SPI 280 /** 281 * Activate a SPI chipselect. 282 * This function is provided by the board code when using a driver 283 * that can't control its chipselects automatically (e.g. 284 * common/soft_spi.c). When called, it should activate the chip select 285 * to the device identified by "slave". 286 */ 287 void spi_cs_activate(struct spi_slave *slave); 288 289 /** 290 * Deactivate a SPI chipselect. 291 * This function is provided by the board code when using a driver 292 * that can't control its chipselects automatically (e.g. 293 * common/soft_spi.c). When called, it should deactivate the chip 294 * select to the device identified by "slave". 295 */ 296 void spi_cs_deactivate(struct spi_slave *slave); 297 298 /** 299 * Set transfer speed. 300 * This sets a new speed to be applied for next spi_xfer(). 301 * @slave: The SPI slave 302 * @hz: The transfer speed 303 */ 304 void spi_set_speed(struct spi_slave *slave, uint hz); 305 #endif 306 307 /** 308 * Write 8 bits, then read 8 bits. 309 * @slave: The SPI slave we're communicating with 310 * @byte: Byte to be written 311 * 312 * Returns: The value that was read, or a negative value on error. 313 * 314 * TODO: This function probably shouldn't be inlined. 315 */ 316 static inline int spi_w8r8(struct spi_slave *slave, unsigned char byte) 317 { 318 unsigned char dout[2]; 319 unsigned char din[2]; 320 int ret; 321 322 dout[0] = byte; 323 dout[1] = 0; 324 325 ret = spi_xfer(slave, 16, dout, din, SPI_XFER_BEGIN | SPI_XFER_END); 326 return ret < 0 ? ret : din[1]; 327 } 328 329 /** 330 * Set up a SPI slave for a particular device tree node 331 * 332 * This calls spi_setup_slave() with the correct bus number. Call 333 * spi_free_slave() to free it later. 334 * 335 * @param blob: Device tree blob 336 * @param slave_node: Slave node to use 337 * @param spi_node: SPI peripheral node to use 338 * @return pointer to new spi_slave structure 339 */ 340 struct spi_slave *spi_setup_slave_fdt(const void *blob, int slave_node, 341 int spi_node); 342 343 /** 344 * spi_base_setup_slave_fdt() - helper function to set up a SPI slace 345 * 346 * This decodes SPI properties from the slave node to determine the 347 * chip select and SPI parameters. 348 * 349 * @blob: Device tree blob 350 * @busnum: Bus number to use 351 * @node: Device tree node for the SPI bus 352 */ 353 struct spi_slave *spi_base_setup_slave_fdt(const void *blob, int busnum, 354 int node); 355 356 #ifdef CONFIG_DM_SPI 357 358 /** 359 * struct spi_cs_info - Information about a bus chip select 360 * 361 * @dev: Connected device, or NULL if none 362 */ 363 struct spi_cs_info { 364 struct udevice *dev; 365 }; 366 367 /** 368 * struct struct dm_spi_ops - Driver model SPI operations 369 * 370 * The uclass interface is implemented by all SPI devices which use 371 * driver model. 372 */ 373 struct dm_spi_ops { 374 /** 375 * Claim the bus and prepare it for communication. 376 * 377 * The device provided is the slave device. It's parent controller 378 * will be used to provide the communication. 379 * 380 * This must be called before doing any transfers with a SPI slave. It 381 * will enable and initialize any SPI hardware as necessary, and make 382 * sure that the SCK line is in the correct idle state. It is not 383 * allowed to claim the same bus for several slaves without releasing 384 * the bus in between. 385 * 386 * @dev: The SPI slave 387 * 388 * Returns: 0 if the bus was claimed successfully, or a negative value 389 * if it wasn't. 390 */ 391 int (*claim_bus)(struct udevice *dev); 392 393 /** 394 * Release the SPI bus 395 * 396 * This must be called once for every call to spi_claim_bus() after 397 * all transfers have finished. It may disable any SPI hardware as 398 * appropriate. 399 * 400 * @dev: The SPI slave 401 */ 402 int (*release_bus)(struct udevice *dev); 403 404 /** 405 * Set the word length for SPI transactions 406 * 407 * Set the word length (number of bits per word) for SPI transactions. 408 * 409 * @bus: The SPI slave 410 * @wordlen: The number of bits in a word 411 * 412 * Returns: 0 on success, -ve on failure. 413 */ 414 int (*set_wordlen)(struct udevice *dev, unsigned int wordlen); 415 416 /** 417 * SPI transfer 418 * 419 * This writes "bitlen" bits out the SPI MOSI port and simultaneously 420 * clocks "bitlen" bits in the SPI MISO port. That's just the way SPI 421 * works. 422 * 423 * The source of the outgoing bits is the "dout" parameter and the 424 * destination of the input bits is the "din" parameter. Note that 425 * "dout" and "din" can point to the same memory location, in which 426 * case the input data overwrites the output data (since both are 427 * buffered by temporary variables, this is OK). 428 * 429 * spi_xfer() interface: 430 * @dev: The slave device to communicate with 431 * @bitlen: How many bits to write and read. 432 * @dout: Pointer to a string of bits to send out. The bits are 433 * held in a byte array and are sent MSB first. 434 * @din: Pointer to a string of bits that will be filled in. 435 * @flags: A bitwise combination of SPI_XFER_* flags. 436 * 437 * Returns: 0 on success, not -1 on failure 438 */ 439 int (*xfer)(struct udevice *dev, unsigned int bitlen, const void *dout, 440 void *din, unsigned long flags); 441 442 /** 443 * Set transfer speed. 444 * This sets a new speed to be applied for next spi_xfer(). 445 * @bus: The SPI bus 446 * @hz: The transfer speed 447 * @return 0 if OK, -ve on error 448 */ 449 int (*set_speed)(struct udevice *bus, uint hz); 450 451 /** 452 * Set the SPI mode/flags 453 * 454 * It is unclear if we want to set speed and mode together instead 455 * of separately. 456 * 457 * @bus: The SPI bus 458 * @mode: Requested SPI mode (SPI_... flags) 459 * @return 0 if OK, -ve on error 460 */ 461 int (*set_mode)(struct udevice *bus, uint mode); 462 463 /** 464 * Get information on a chip select 465 * 466 * This is only called when the SPI uclass does not know about a 467 * chip select, i.e. it has no attached device. It gives the driver 468 * a chance to allow activity on that chip select even so. 469 * 470 * @bus: The SPI bus 471 * @cs: The chip select (0..n-1) 472 * @info: Returns information about the chip select, if valid. 473 * On entry info->dev is NULL 474 * @return 0 if OK (and @info is set up), -ENODEV if the chip select 475 * is invalid, other -ve value on error 476 */ 477 int (*cs_info)(struct udevice *bus, uint cs, struct spi_cs_info *info); 478 }; 479 480 struct dm_spi_emul_ops { 481 /** 482 * SPI transfer 483 * 484 * This writes "bitlen" bits out the SPI MOSI port and simultaneously 485 * clocks "bitlen" bits in the SPI MISO port. That's just the way SPI 486 * works. Here the device is a slave. 487 * 488 * The source of the outgoing bits is the "dout" parameter and the 489 * destination of the input bits is the "din" parameter. Note that 490 * "dout" and "din" can point to the same memory location, in which 491 * case the input data overwrites the output data (since both are 492 * buffered by temporary variables, this is OK). 493 * 494 * spi_xfer() interface: 495 * @slave: The SPI slave which will be sending/receiving the data. 496 * @bitlen: How many bits to write and read. 497 * @dout: Pointer to a string of bits sent to the device. The 498 * bits are held in a byte array and are sent MSB first. 499 * @din: Pointer to a string of bits that will be sent back to 500 * the master. 501 * @flags: A bitwise combination of SPI_XFER_* flags. 502 * 503 * Returns: 0 on success, not -1 on failure 504 */ 505 int (*xfer)(struct udevice *slave, unsigned int bitlen, 506 const void *dout, void *din, unsigned long flags); 507 }; 508 509 /** 510 * spi_find_bus_and_cs() - Find bus and slave devices by number 511 * 512 * Given a bus number and chip select, this finds the corresponding bus 513 * device and slave device. Neither device is activated by this function, 514 * although they may have been activated previously. 515 * 516 * @busnum: SPI bus number 517 * @cs: Chip select to look for 518 * @busp: Returns bus device 519 * @devp: Return slave device 520 * @return 0 if found, -ENODEV on error 521 */ 522 int spi_find_bus_and_cs(int busnum, int cs, struct udevice **busp, 523 struct udevice **devp); 524 525 /** 526 * spi_get_bus_and_cs() - Find and activate bus and slave devices by number 527 * 528 * Given a bus number and chip select, this finds the corresponding bus 529 * device and slave device. 530 * 531 * If no such slave exists, and drv_name is not NULL, then a new slave device 532 * is automatically bound on this chip select. 533 * 534 * Ths new slave device is probed ready for use with the given speed and mode. 535 * 536 * @busnum: SPI bus number 537 * @cs: Chip select to look for 538 * @speed: SPI speed to use for this slave 539 * @mode: SPI mode to use for this slave 540 * @drv_name: Name of driver to attach to this chip select 541 * @dev_name: Name of the new device thus created 542 * @busp: Returns bus device 543 * @devp: Return slave device 544 * @return 0 if found, -ve on error 545 */ 546 int spi_get_bus_and_cs(int busnum, int cs, int speed, int mode, 547 const char *drv_name, const char *dev_name, 548 struct udevice **busp, struct spi_slave **devp); 549 550 /** 551 * spi_chip_select() - Get the chip select for a slave 552 * 553 * @return the chip select this slave is attached to 554 */ 555 int spi_chip_select(struct udevice *slave); 556 557 /** 558 * spi_find_chip_select() - Find the slave attached to chip select 559 * 560 * @bus: SPI bus to search 561 * @cs: Chip select to look for 562 * @devp: Returns the slave device if found 563 * @return 0 if found, -ENODEV on error 564 */ 565 int spi_find_chip_select(struct udevice *bus, int cs, struct udevice **devp); 566 567 /** 568 * spi_slave_ofdata_to_platdata() - decode standard SPI platform data 569 * 570 * This decodes the speed and mode for a slave from a device tree node 571 * 572 * @blob: Device tree blob 573 * @node: Node offset to read from 574 * @plat: Place to put the decoded information 575 */ 576 int spi_slave_ofdata_to_platdata(const void *blob, int node, 577 struct dm_spi_slave_platdata *plat); 578 579 /** 580 * spi_cs_info() - Check information on a chip select 581 * 582 * This checks a particular chip select on a bus to see if it has a device 583 * attached, or is even valid. 584 * 585 * @bus: The SPI bus 586 * @cs: The chip select (0..n-1) 587 * @info: Returns information about the chip select, if valid 588 * @return 0 if OK (and @info is set up), -ENODEV if the chip select 589 * is invalid, other -ve value on error 590 */ 591 int spi_cs_info(struct udevice *bus, uint cs, struct spi_cs_info *info); 592 593 struct sandbox_state; 594 595 /** 596 * sandbox_spi_get_emul() - get an emulator for a SPI slave 597 * 598 * This provides a way to attach an emulated SPI device to a particular SPI 599 * slave, so that xfer() operations on the slave will be handled by the 600 * emulator. If a emulator already exists on that chip select it is returned. 601 * Otherwise one is created. 602 * 603 * @state: Sandbox state 604 * @bus: SPI bus requesting the emulator 605 * @slave: SPI slave device requesting the emulator 606 * @emuip: Returns pointer to emulator 607 * @return 0 if OK, -ve on error 608 */ 609 int sandbox_spi_get_emul(struct sandbox_state *state, 610 struct udevice *bus, struct udevice *slave, 611 struct udevice **emulp); 612 613 /* Access the operations for a SPI device */ 614 #define spi_get_ops(dev) ((struct dm_spi_ops *)(dev)->driver->ops) 615 #define spi_emul_get_ops(dev) ((struct dm_spi_emul_ops *)(dev)->driver->ops) 616 #endif /* CONFIG_DM_SPI */ 617 618 #endif /* _SPI_H_ */ 619