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 * @mode_rx: SPI RX mode to use for this slave (see SPI mode_rx flags) 65 */ 66 struct dm_spi_slave_platdata { 67 unsigned int cs; 68 uint max_hz; 69 uint mode; 70 u8 mode_rx; 71 }; 72 73 #endif /* CONFIG_DM_SPI */ 74 75 /** 76 * struct spi_slave - Representation of a SPI slave 77 * 78 * For driver model this is the per-child data used by the SPI bus. It can 79 * be accessed using dev_get_parent_priv() on the slave device. The SPI uclass 80 * sets uip per_child_auto_alloc_size to sizeof(struct spi_slave), and the 81 * driver should not override it. Two platform data fields (max_hz and mode) 82 * are copied into this structure to provide an initial value. This allows 83 * them to be changed, since we should never change platform data in drivers. 84 * 85 * If not using driver model, drivers are expected to extend this with 86 * controller-specific data. 87 * 88 * @dev: SPI slave device 89 * @max_hz: Maximum speed for this slave 90 * @speed: Current bus speed. This is 0 until the bus is first 91 * claimed. 92 * @bus: ID of the bus that the slave is attached to. For 93 * driver model this is the sequence number of the SPI 94 * bus (bus->seq) so does not need to be stored 95 * @cs: ID of the chip select connected to the slave. 96 * @mode: SPI mode to use for this slave (see SPI mode flags) 97 * @mode_rx: SPI RX mode to use for this slave (see SPI mode_rx flags) 98 * @wordlen: Size of SPI word in number of bits 99 * @max_write_size: If non-zero, the maximum number of bytes which can 100 * be written at once, excluding command bytes. 101 * @memory_map: Address of read-only SPI flash access. 102 * @option: Varies SPI bus options - separate, shared bus. 103 * @flags: Indication of SPI flags. 104 */ 105 struct spi_slave { 106 #ifdef CONFIG_DM_SPI 107 struct udevice *dev; /* struct spi_slave is dev->parentdata */ 108 uint max_hz; 109 uint speed; 110 #else 111 unsigned int bus; 112 unsigned int cs; 113 #endif 114 uint mode; 115 u8 mode_rx; 116 unsigned int wordlen; 117 unsigned int max_write_size; 118 void *memory_map; 119 u8 option; 120 121 u8 flags; 122 #define SPI_XFER_BEGIN BIT(0) /* Assert CS before transfer */ 123 #define SPI_XFER_END BIT(1) /* Deassert CS after transfer */ 124 #define SPI_XFER_ONCE (SPI_XFER_BEGIN | SPI_XFER_END) 125 #define SPI_XFER_MMAP BIT(2) /* Memory Mapped start */ 126 #define SPI_XFER_MMAP_END BIT(3) /* Memory Mapped End */ 127 #define SPI_XFER_U_PAGE BIT(4) 128 }; 129 130 /** 131 * Initialization, must be called once on start up. 132 * 133 * TODO: I don't think we really need this. 134 */ 135 void spi_init(void); 136 137 /** 138 * spi_do_alloc_slave - Allocate a new SPI slave (internal) 139 * 140 * Allocate and zero all fields in the spi slave, and set the bus/chip 141 * select. Use the helper macro spi_alloc_slave() to call this. 142 * 143 * @offset: Offset of struct spi_slave within slave structure. 144 * @size: Size of slave structure. 145 * @bus: Bus ID of the slave chip. 146 * @cs: Chip select ID of the slave chip on the specified bus. 147 */ 148 void *spi_do_alloc_slave(int offset, int size, unsigned int bus, 149 unsigned int cs); 150 151 /** 152 * spi_alloc_slave - Allocate a new SPI slave 153 * 154 * Allocate and zero all fields in the spi slave, and set the bus/chip 155 * select. 156 * 157 * @_struct: Name of structure to allocate (e.g. struct tegra_spi). 158 * This structure must contain a member 'struct spi_slave *slave'. 159 * @bus: Bus ID of the slave chip. 160 * @cs: Chip select ID of the slave chip on the specified bus. 161 */ 162 #define spi_alloc_slave(_struct, bus, cs) \ 163 spi_do_alloc_slave(offsetof(_struct, slave), \ 164 sizeof(_struct), bus, cs) 165 166 /** 167 * spi_alloc_slave_base - Allocate a new SPI slave with no private data 168 * 169 * Allocate and zero all fields in the spi slave, and set the bus/chip 170 * select. 171 * 172 * @bus: Bus ID of the slave chip. 173 * @cs: Chip select ID of the slave chip on the specified bus. 174 */ 175 #define spi_alloc_slave_base(bus, cs) \ 176 spi_do_alloc_slave(0, sizeof(struct spi_slave), bus, cs) 177 178 /** 179 * Set up communications parameters for a SPI slave. 180 * 181 * This must be called once for each slave. Note that this function 182 * usually doesn't touch any actual hardware, it only initializes the 183 * contents of spi_slave so that the hardware can be easily 184 * initialized later. 185 * 186 * @bus: Bus ID of the slave chip. 187 * @cs: Chip select ID of the slave chip on the specified bus. 188 * @max_hz: Maximum SCK rate in Hz. 189 * @mode: Clock polarity, clock phase and other parameters. 190 * 191 * Returns: A spi_slave reference that can be used in subsequent SPI 192 * calls, or NULL if one or more of the parameters are not supported. 193 */ 194 struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs, 195 unsigned int max_hz, unsigned int mode); 196 197 /** 198 * Free any memory associated with a SPI slave. 199 * 200 * @slave: The SPI slave 201 */ 202 void spi_free_slave(struct spi_slave *slave); 203 204 /** 205 * Claim the bus and prepare it for communication with a given slave. 206 * 207 * This must be called before doing any transfers with a SPI slave. It 208 * will enable and initialize any SPI hardware as necessary, and make 209 * sure that the SCK line is in the correct idle state. It is not 210 * allowed to claim the same bus for several slaves without releasing 211 * the bus in between. 212 * 213 * @slave: The SPI slave 214 * 215 * Returns: 0 if the bus was claimed successfully, or a negative value 216 * if it wasn't. 217 */ 218 int spi_claim_bus(struct spi_slave *slave); 219 220 /** 221 * Release the SPI bus 222 * 223 * This must be called once for every call to spi_claim_bus() after 224 * all transfers have finished. It may disable any SPI hardware as 225 * appropriate. 226 * 227 * @slave: The SPI slave 228 */ 229 void spi_release_bus(struct spi_slave *slave); 230 231 /** 232 * Set the word length for SPI transactions 233 * 234 * Set the word length (number of bits per word) for SPI transactions. 235 * 236 * @slave: The SPI slave 237 * @wordlen: The number of bits in a word 238 * 239 * Returns: 0 on success, -1 on failure. 240 */ 241 int spi_set_wordlen(struct spi_slave *slave, unsigned int wordlen); 242 243 /** 244 * SPI transfer 245 * 246 * This writes "bitlen" bits out the SPI MOSI port and simultaneously clocks 247 * "bitlen" bits in the SPI MISO port. That's just the way SPI works. 248 * 249 * The source of the outgoing bits is the "dout" parameter and the 250 * destination of the input bits is the "din" parameter. Note that "dout" 251 * and "din" can point to the same memory location, in which case the 252 * input data overwrites the output data (since both are buffered by 253 * temporary variables, this is OK). 254 * 255 * spi_xfer() interface: 256 * @slave: The SPI slave which will be sending/receiving the data. 257 * @bitlen: How many bits to write and read. 258 * @dout: Pointer to a string of bits to send out. The bits are 259 * held in a byte array and are sent MSB first. 260 * @din: Pointer to a string of bits that will be filled in. 261 * @flags: A bitwise combination of SPI_XFER_* flags. 262 * 263 * Returns: 0 on success, not 0 on failure 264 */ 265 int spi_xfer(struct spi_slave *slave, unsigned int bitlen, const void *dout, 266 void *din, unsigned long flags); 267 268 /* Copy memory mapped data */ 269 void spi_flash_copy_mmap(void *data, void *offset, size_t len); 270 271 /** 272 * Determine if a SPI chipselect is valid. 273 * This function is provided by the board if the low-level SPI driver 274 * needs it to determine if a given chipselect is actually valid. 275 * 276 * Returns: 1 if bus:cs identifies a valid chip on this board, 0 277 * otherwise. 278 */ 279 int spi_cs_is_valid(unsigned int bus, unsigned int cs); 280 281 #ifndef CONFIG_DM_SPI 282 /** 283 * Activate a SPI chipselect. 284 * This function is provided by the board code when using a driver 285 * that can't control its chipselects automatically (e.g. 286 * common/soft_spi.c). When called, it should activate the chip select 287 * to the device identified by "slave". 288 */ 289 void spi_cs_activate(struct spi_slave *slave); 290 291 /** 292 * Deactivate a SPI chipselect. 293 * This function is provided by the board code when using a driver 294 * that can't control its chipselects automatically (e.g. 295 * common/soft_spi.c). When called, it should deactivate the chip 296 * select to the device identified by "slave". 297 */ 298 void spi_cs_deactivate(struct spi_slave *slave); 299 300 /** 301 * Set transfer speed. 302 * This sets a new speed to be applied for next spi_xfer(). 303 * @slave: The SPI slave 304 * @hz: The transfer speed 305 */ 306 void spi_set_speed(struct spi_slave *slave, uint hz); 307 #endif 308 309 /** 310 * Write 8 bits, then read 8 bits. 311 * @slave: The SPI slave we're communicating with 312 * @byte: Byte to be written 313 * 314 * Returns: The value that was read, or a negative value on error. 315 * 316 * TODO: This function probably shouldn't be inlined. 317 */ 318 static inline int spi_w8r8(struct spi_slave *slave, unsigned char byte) 319 { 320 unsigned char dout[2]; 321 unsigned char din[2]; 322 int ret; 323 324 dout[0] = byte; 325 dout[1] = 0; 326 327 ret = spi_xfer(slave, 16, dout, din, SPI_XFER_BEGIN | SPI_XFER_END); 328 return ret < 0 ? ret : din[1]; 329 } 330 331 /** 332 * Set up a SPI slave for a particular device tree node 333 * 334 * This calls spi_setup_slave() with the correct bus number. Call 335 * spi_free_slave() to free it later. 336 * 337 * @param blob: Device tree blob 338 * @param slave_node: Slave node to use 339 * @param spi_node: SPI peripheral node to use 340 * @return pointer to new spi_slave structure 341 */ 342 struct spi_slave *spi_setup_slave_fdt(const void *blob, int slave_node, 343 int spi_node); 344 345 /** 346 * spi_base_setup_slave_fdt() - helper function to set up a SPI slace 347 * 348 * This decodes SPI properties from the slave node to determine the 349 * chip select and SPI parameters. 350 * 351 * @blob: Device tree blob 352 * @busnum: Bus number to use 353 * @node: Device tree node for the SPI bus 354 */ 355 struct spi_slave *spi_base_setup_slave_fdt(const void *blob, int busnum, 356 int node); 357 358 #ifdef CONFIG_DM_SPI 359 360 /** 361 * struct spi_cs_info - Information about a bus chip select 362 * 363 * @dev: Connected device, or NULL if none 364 */ 365 struct spi_cs_info { 366 struct udevice *dev; 367 }; 368 369 /** 370 * struct struct dm_spi_ops - Driver model SPI operations 371 * 372 * The uclass interface is implemented by all SPI devices which use 373 * driver model. 374 */ 375 struct dm_spi_ops { 376 /** 377 * Claim the bus and prepare it for communication. 378 * 379 * The device provided is the slave device. It's parent controller 380 * will be used to provide the communication. 381 * 382 * This must be called before doing any transfers with a SPI slave. It 383 * will enable and initialize any SPI hardware as necessary, and make 384 * sure that the SCK line is in the correct idle state. It is not 385 * allowed to claim the same bus for several slaves without releasing 386 * the bus in between. 387 * 388 * @dev: The SPI slave 389 * 390 * Returns: 0 if the bus was claimed successfully, or a negative value 391 * if it wasn't. 392 */ 393 int (*claim_bus)(struct udevice *dev); 394 395 /** 396 * Release the SPI bus 397 * 398 * This must be called once for every call to spi_claim_bus() after 399 * all transfers have finished. It may disable any SPI hardware as 400 * appropriate. 401 * 402 * @dev: The SPI slave 403 */ 404 int (*release_bus)(struct udevice *dev); 405 406 /** 407 * Set the word length for SPI transactions 408 * 409 * Set the word length (number of bits per word) for SPI transactions. 410 * 411 * @bus: The SPI slave 412 * @wordlen: The number of bits in a word 413 * 414 * Returns: 0 on success, -ve on failure. 415 */ 416 int (*set_wordlen)(struct udevice *dev, unsigned int wordlen); 417 418 /** 419 * SPI transfer 420 * 421 * This writes "bitlen" bits out the SPI MOSI port and simultaneously 422 * clocks "bitlen" bits in the SPI MISO port. That's just the way SPI 423 * works. 424 * 425 * The source of the outgoing bits is the "dout" parameter and the 426 * destination of the input bits is the "din" parameter. Note that 427 * "dout" and "din" can point to the same memory location, in which 428 * case the input data overwrites the output data (since both are 429 * buffered by temporary variables, this is OK). 430 * 431 * spi_xfer() interface: 432 * @dev: The slave device to communicate with 433 * @bitlen: How many bits to write and read. 434 * @dout: Pointer to a string of bits to send out. The bits are 435 * held in a byte array and are sent MSB first. 436 * @din: Pointer to a string of bits that will be filled in. 437 * @flags: A bitwise combination of SPI_XFER_* flags. 438 * 439 * Returns: 0 on success, not -1 on failure 440 */ 441 int (*xfer)(struct udevice *dev, unsigned int bitlen, const void *dout, 442 void *din, unsigned long flags); 443 444 /** 445 * Set transfer speed. 446 * This sets a new speed to be applied for next spi_xfer(). 447 * @bus: The SPI bus 448 * @hz: The transfer speed 449 * @return 0 if OK, -ve on error 450 */ 451 int (*set_speed)(struct udevice *bus, uint hz); 452 453 /** 454 * Set the SPI mode/flags 455 * 456 * It is unclear if we want to set speed and mode together instead 457 * of separately. 458 * 459 * @bus: The SPI bus 460 * @mode: Requested SPI mode (SPI_... flags) 461 * @return 0 if OK, -ve on error 462 */ 463 int (*set_mode)(struct udevice *bus, uint mode); 464 465 /** 466 * Get information on a chip select 467 * 468 * This is only called when the SPI uclass does not know about a 469 * chip select, i.e. it has no attached device. It gives the driver 470 * a chance to allow activity on that chip select even so. 471 * 472 * @bus: The SPI bus 473 * @cs: The chip select (0..n-1) 474 * @info: Returns information about the chip select, if valid. 475 * On entry info->dev is NULL 476 * @return 0 if OK (and @info is set up), -ENODEV if the chip select 477 * is invalid, other -ve value on error 478 */ 479 int (*cs_info)(struct udevice *bus, uint cs, struct spi_cs_info *info); 480 }; 481 482 struct dm_spi_emul_ops { 483 /** 484 * SPI transfer 485 * 486 * This writes "bitlen" bits out the SPI MOSI port and simultaneously 487 * clocks "bitlen" bits in the SPI MISO port. That's just the way SPI 488 * works. Here the device is a slave. 489 * 490 * The source of the outgoing bits is the "dout" parameter and the 491 * destination of the input bits is the "din" parameter. Note that 492 * "dout" and "din" can point to the same memory location, in which 493 * case the input data overwrites the output data (since both are 494 * buffered by temporary variables, this is OK). 495 * 496 * spi_xfer() interface: 497 * @slave: The SPI slave which will be sending/receiving the data. 498 * @bitlen: How many bits to write and read. 499 * @dout: Pointer to a string of bits sent to the device. The 500 * bits are held in a byte array and are sent MSB first. 501 * @din: Pointer to a string of bits that will be sent back to 502 * the master. 503 * @flags: A bitwise combination of SPI_XFER_* flags. 504 * 505 * Returns: 0 on success, not -1 on failure 506 */ 507 int (*xfer)(struct udevice *slave, unsigned int bitlen, 508 const void *dout, void *din, unsigned long flags); 509 }; 510 511 /** 512 * spi_find_bus_and_cs() - Find bus and slave devices by number 513 * 514 * Given a bus number and chip select, this finds the corresponding bus 515 * device and slave device. Neither device is activated by this function, 516 * although they may have been activated previously. 517 * 518 * @busnum: SPI bus number 519 * @cs: Chip select to look for 520 * @busp: Returns bus device 521 * @devp: Return slave device 522 * @return 0 if found, -ENODEV on error 523 */ 524 int spi_find_bus_and_cs(int busnum, int cs, struct udevice **busp, 525 struct udevice **devp); 526 527 /** 528 * spi_get_bus_and_cs() - Find and activate bus and slave devices by number 529 * 530 * Given a bus number and chip select, this finds the corresponding bus 531 * device and slave device. 532 * 533 * If no such slave exists, and drv_name is not NULL, then a new slave device 534 * is automatically bound on this chip select. 535 * 536 * Ths new slave device is probed ready for use with the given speed and mode. 537 * 538 * @busnum: SPI bus number 539 * @cs: Chip select to look for 540 * @speed: SPI speed to use for this slave 541 * @mode: SPI mode to use for this slave 542 * @drv_name: Name of driver to attach to this chip select 543 * @dev_name: Name of the new device thus created 544 * @busp: Returns bus device 545 * @devp: Return slave device 546 * @return 0 if found, -ve on error 547 */ 548 int spi_get_bus_and_cs(int busnum, int cs, int speed, int mode, 549 const char *drv_name, const char *dev_name, 550 struct udevice **busp, struct spi_slave **devp); 551 552 /** 553 * spi_chip_select() - Get the chip select for a slave 554 * 555 * @return the chip select this slave is attached to 556 */ 557 int spi_chip_select(struct udevice *slave); 558 559 /** 560 * spi_find_chip_select() - Find the slave attached to chip select 561 * 562 * @bus: SPI bus to search 563 * @cs: Chip select to look for 564 * @devp: Returns the slave device if found 565 * @return 0 if found, -ENODEV on error 566 */ 567 int spi_find_chip_select(struct udevice *bus, int cs, struct udevice **devp); 568 569 /** 570 * spi_slave_ofdata_to_platdata() - decode standard SPI platform data 571 * 572 * This decodes the speed and mode for a slave from a device tree node 573 * 574 * @blob: Device tree blob 575 * @node: Node offset to read from 576 * @plat: Place to put the decoded information 577 */ 578 int spi_slave_ofdata_to_platdata(const void *blob, int node, 579 struct dm_spi_slave_platdata *plat); 580 581 /** 582 * spi_cs_info() - Check information on a chip select 583 * 584 * This checks a particular chip select on a bus to see if it has a device 585 * attached, or is even valid. 586 * 587 * @bus: The SPI bus 588 * @cs: The chip select (0..n-1) 589 * @info: Returns information about the chip select, if valid 590 * @return 0 if OK (and @info is set up), -ENODEV if the chip select 591 * is invalid, other -ve value on error 592 */ 593 int spi_cs_info(struct udevice *bus, uint cs, struct spi_cs_info *info); 594 595 struct sandbox_state; 596 597 /** 598 * sandbox_spi_get_emul() - get an emulator for a SPI slave 599 * 600 * This provides a way to attach an emulated SPI device to a particular SPI 601 * slave, so that xfer() operations on the slave will be handled by the 602 * emulator. If a emulator already exists on that chip select it is returned. 603 * Otherwise one is created. 604 * 605 * @state: Sandbox state 606 * @bus: SPI bus requesting the emulator 607 * @slave: SPI slave device requesting the emulator 608 * @emuip: Returns pointer to emulator 609 * @return 0 if OK, -ve on error 610 */ 611 int sandbox_spi_get_emul(struct sandbox_state *state, 612 struct udevice *bus, struct udevice *slave, 613 struct udevice **emulp); 614 615 /* Access the operations for a SPI device */ 616 #define spi_get_ops(dev) ((struct dm_spi_ops *)(dev)->driver->ops) 617 #define spi_emul_get_ops(dev) ((struct dm_spi_emul_ops *)(dev)->driver->ops) 618 #endif /* CONFIG_DM_SPI */ 619 620 #endif /* _SPI_H_ */ 621