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 #include <common.h> 14 15 /* SPI mode flags */ 16 #define SPI_CPHA BIT(0) /* clock phase */ 17 #define SPI_CPOL BIT(1) /* clock polarity */ 18 #define SPI_MODE_0 (0|0) /* (original MicroWire) */ 19 #define SPI_MODE_1 (0|SPI_CPHA) 20 #define SPI_MODE_2 (SPI_CPOL|0) 21 #define SPI_MODE_3 (SPI_CPOL|SPI_CPHA) 22 #define SPI_CS_HIGH BIT(2) /* CS active high */ 23 #define SPI_LSB_FIRST BIT(3) /* per-word bits-on-wire */ 24 #define SPI_3WIRE BIT(4) /* SI/SO signals shared */ 25 #define SPI_LOOP BIT(5) /* loopback mode */ 26 #define SPI_SLAVE BIT(6) /* slave mode */ 27 #define SPI_PREAMBLE BIT(7) /* Skip preamble bytes */ 28 #define SPI_TX_BYTE BIT(8) /* transmit with 1 wire byte */ 29 #define SPI_TX_DUAL BIT(9) /* transmit with 2 wires */ 30 #define SPI_TX_QUAD BIT(10) /* transmit with 4 wires */ 31 #define SPI_RX_SLOW BIT(11) /* receive with 1 wire slow */ 32 #define SPI_RX_DUAL BIT(12) /* receive with 2 wires */ 33 #define SPI_RX_QUAD BIT(13) /* receive with 4 wires */ 34 #define SPI_TX_OCTAL BIT(14) /* transmit with 8 wires */ 35 #define SPI_RX_OCTAL BIT(15) /* receive with 8 wires */ 36 #define SPI_DMA_PREPARE BIT(24) /* dma transfer skip waiting idle, read without cache invalid */ 37 38 /* Header byte that marks the start of the message */ 39 #define SPI_PREAMBLE_END_BYTE 0xec 40 41 #define SPI_DEFAULT_WORDLEN 8 42 43 /** 44 * struct dm_spi_bus - SPI bus info 45 * 46 * This contains information about a SPI bus. To obtain this structure, use 47 * dev_get_uclass_priv(bus) where bus is the SPI bus udevice. 48 * 49 * @max_hz: Maximum speed that the bus can tolerate. 50 * @speed: Current bus speed. This is 0 until the bus is first claimed. 51 * @mode: Current bus mode. This is 0 until the bus is first claimed. 52 * 53 * TODO(sjg@chromium.org): Remove this and use max_hz from struct spi_slave. 54 */ 55 struct dm_spi_bus { 56 uint max_hz; 57 uint speed; 58 uint mode; 59 }; 60 61 /** 62 * struct dm_spi_platdata - platform data for all SPI slaves 63 * 64 * This describes a SPI slave, a child device of the SPI bus. To obtain this 65 * struct from a spi_slave, use dev_get_parent_platdata(dev) or 66 * dev_get_parent_platdata(slave->dev). 67 * 68 * This data is immuatable. Each time the device is probed, @max_hz and @mode 69 * will be copied to struct spi_slave. 70 * 71 * @cs: Chip select number (0..n-1) 72 * @max_hz: Maximum bus speed that this slave can tolerate 73 * @mode: SPI mode to use for this device (see SPI mode flags) 74 */ 75 struct dm_spi_slave_platdata { 76 unsigned int cs; 77 uint max_hz; 78 uint mode; 79 }; 80 81 /** 82 * struct spi_slave - Representation of a SPI slave 83 * 84 * For driver model this is the per-child data used by the SPI bus. It can 85 * be accessed using dev_get_parent_priv() on the slave device. The SPI uclass 86 * sets uip per_child_auto_alloc_size to sizeof(struct spi_slave), and the 87 * driver should not override it. Two platform data fields (max_hz and mode) 88 * are copied into this structure to provide an initial value. This allows 89 * them to be changed, since we should never change platform data in drivers. 90 * 91 * If not using driver model, drivers are expected to extend this with 92 * controller-specific data. 93 * 94 * @dev: SPI slave device 95 * @max_hz: Maximum speed for this slave 96 * @bus: ID of the bus that the slave is attached to. For 97 * driver model this is the sequence number of the SPI 98 * bus (bus->seq) so does not need to be stored 99 * @cs: ID of the chip select connected to the slave. 100 * @mode: SPI mode to use for this slave (see SPI mode flags) 101 * @wordlen: Size of SPI word in number of bits 102 * @max_read_size: If non-zero, the maximum number of bytes which can 103 * be read at once. 104 * @max_write_size: If non-zero, the maximum number of bytes which can 105 * be written at once. 106 * @memory_map: Address of read-only SPI flash access. 107 * @flags: Indication of SPI flags. 108 */ 109 struct spi_slave { 110 #ifdef CONFIG_DM_SPI 111 struct udevice *dev; /* struct spi_slave is dev->parentdata */ 112 uint max_hz; 113 #else 114 unsigned int bus; 115 unsigned int cs; 116 #endif 117 #ifdef CONFIG_SPI_FLASH_AUTO_MERGE 118 unsigned int auto_merge_cs_cur; 119 #endif 120 uint mode; 121 unsigned int wordlen; 122 unsigned int max_read_size; 123 unsigned int max_write_size; 124 void *memory_map; 125 u8 option; 126 127 u8 flags; 128 #define SPI_XFER_BEGIN BIT(0) /* Assert CS before transfer */ 129 #define SPI_XFER_END BIT(1) /* Deassert CS after transfer */ 130 #define SPI_XFER_ONCE (SPI_XFER_BEGIN | SPI_XFER_END) 131 #define SPI_XFER_MMAP BIT(2) /* Memory Mapped start */ 132 #define SPI_XFER_MMAP_END BIT(3) /* Memory Mapped End */ 133 #define SPI_XFER_PREPARE BIT(7) /* Transfer skip waiting idle */ 134 }; 135 136 /** 137 * Initialization, must be called once on start up. 138 * 139 * TODO: I don't think we really need this. 140 */ 141 void spi_init(void); 142 143 /** 144 * spi_do_alloc_slave - Allocate a new SPI slave (internal) 145 * 146 * Allocate and zero all fields in the spi slave, and set the bus/chip 147 * select. Use the helper macro spi_alloc_slave() to call this. 148 * 149 * @offset: Offset of struct spi_slave within slave structure. 150 * @size: Size of slave structure. 151 * @bus: Bus ID of the slave chip. 152 * @cs: Chip select ID of the slave chip on the specified bus. 153 */ 154 void *spi_do_alloc_slave(int offset, int size, unsigned int bus, 155 unsigned int cs); 156 157 /** 158 * spi_alloc_slave - Allocate a new SPI slave 159 * 160 * Allocate and zero all fields in the spi slave, and set the bus/chip 161 * select. 162 * 163 * @_struct: Name of structure to allocate (e.g. struct tegra_spi). 164 * This structure must contain a member 'struct spi_slave *slave'. 165 * @bus: Bus ID of the slave chip. 166 * @cs: Chip select ID of the slave chip on the specified bus. 167 */ 168 #define spi_alloc_slave(_struct, bus, cs) \ 169 spi_do_alloc_slave(offsetof(_struct, slave), \ 170 sizeof(_struct), bus, cs) 171 172 /** 173 * spi_alloc_slave_base - Allocate a new SPI slave with no private data 174 * 175 * Allocate and zero all fields in the spi slave, and set the bus/chip 176 * select. 177 * 178 * @bus: Bus ID of the slave chip. 179 * @cs: Chip select ID of the slave chip on the specified bus. 180 */ 181 #define spi_alloc_slave_base(bus, cs) \ 182 spi_do_alloc_slave(0, sizeof(struct spi_slave), bus, cs) 183 184 /** 185 * Set up communications parameters for a SPI slave. 186 * 187 * This must be called once for each slave. Note that this function 188 * usually doesn't touch any actual hardware, it only initializes the 189 * contents of spi_slave so that the hardware can be easily 190 * initialized later. 191 * 192 * @bus: Bus ID of the slave chip. 193 * @cs: Chip select ID of the slave chip on the specified bus. 194 * @max_hz: Maximum SCK rate in Hz. 195 * @mode: Clock polarity, clock phase and other parameters. 196 * 197 * Returns: A spi_slave reference that can be used in subsequent SPI 198 * calls, or NULL if one or more of the parameters are not supported. 199 */ 200 struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs, 201 unsigned int max_hz, unsigned int mode); 202 203 /** 204 * Free any memory associated with a SPI slave. 205 * 206 * @slave: The SPI slave 207 */ 208 void spi_free_slave(struct spi_slave *slave); 209 210 /** 211 * Claim the bus and prepare it for communication with a given slave. 212 * 213 * This must be called before doing any transfers with a SPI slave. It 214 * will enable and initialize any SPI hardware as necessary, and make 215 * sure that the SCK line is in the correct idle state. It is not 216 * allowed to claim the same bus for several slaves without releasing 217 * the bus in between. 218 * 219 * @slave: The SPI slave 220 * 221 * Returns: 0 if the bus was claimed successfully, or a negative value 222 * if it wasn't. 223 */ 224 int spi_claim_bus(struct spi_slave *slave); 225 226 /** 227 * Release the SPI bus 228 * 229 * This must be called once for every call to spi_claim_bus() after 230 * all transfers have finished. It may disable any SPI hardware as 231 * appropriate. 232 * 233 * @slave: The SPI slave 234 */ 235 void spi_release_bus(struct spi_slave *slave); 236 237 /** 238 * Set the word length for SPI transactions 239 * 240 * Set the word length (number of bits per word) for SPI transactions. 241 * 242 * @slave: The SPI slave 243 * @wordlen: The number of bits in a word 244 * 245 * Returns: 0 on success, -1 on failure. 246 */ 247 int spi_set_wordlen(struct spi_slave *slave, unsigned int wordlen); 248 249 /** 250 * SPI transfer (optional if mem_ops is used) 251 * 252 * This writes "bitlen" bits out the SPI MOSI port and simultaneously clocks 253 * "bitlen" bits in the SPI MISO port. That's just the way SPI works. 254 * 255 * The source of the outgoing bits is the "dout" parameter and the 256 * destination of the input bits is the "din" parameter. Note that "dout" 257 * and "din" can point to the same memory location, in which case the 258 * input data overwrites the output data (since both are buffered by 259 * temporary variables, this is OK). 260 * 261 * spi_xfer() interface: 262 * @slave: The SPI slave which will be sending/receiving the data. 263 * @bitlen: How many bits to write and read. 264 * @dout: Pointer to a string of bits to send out. The bits are 265 * held in a byte array and are sent MSB first. 266 * @din: Pointer to a string of bits that will be filled in. 267 * @flags: A bitwise combination of SPI_XFER_* flags. 268 * 269 * Returns: 0 on success, not 0 on failure 270 */ 271 int spi_xfer(struct spi_slave *slave, unsigned int bitlen, const void *dout, 272 void *din, unsigned long flags); 273 274 /** 275 * spi_write_then_read - SPI synchronous write followed by read 276 * 277 * This performs a half duplex transaction in which the first transaction 278 * is to send the opcode and if the length of buf is non-zero then it start 279 * the second transaction as tx or rx based on the need from respective slave. 280 * 281 * @slave: The SPI slave device with which opcode/data will be exchanged 282 * @opcode: opcode used for specific transfer 283 * @n_opcode: size of opcode, in bytes 284 * @txbuf: buffer into which data to be written 285 * @rxbuf: buffer into which data will be read 286 * @n_buf: size of buf (whether it's [tx|rx]buf), in bytes 287 * 288 * Returns: 0 on success, not 0 on failure 289 */ 290 int spi_write_then_read(struct spi_slave *slave, const u8 *opcode, 291 size_t n_opcode, const u8 *txbuf, u8 *rxbuf, 292 size_t n_buf); 293 294 /* Copy memory mapped data */ 295 void spi_flash_copy_mmap(void *data, void *offset, size_t len); 296 297 /** 298 * Determine if a SPI chipselect is valid. 299 * This function is provided by the board if the low-level SPI driver 300 * needs it to determine if a given chipselect is actually valid. 301 * 302 * Returns: 1 if bus:cs identifies a valid chip on this board, 0 303 * otherwise. 304 */ 305 int spi_cs_is_valid(unsigned int bus, unsigned int cs); 306 307 #ifndef CONFIG_DM_SPI 308 /** 309 * Activate a SPI chipselect. 310 * This function is provided by the board code when using a driver 311 * that can't control its chipselects automatically (e.g. 312 * common/soft_spi.c). When called, it should activate the chip select 313 * to the device identified by "slave". 314 */ 315 void spi_cs_activate(struct spi_slave *slave); 316 317 /** 318 * Deactivate a SPI chipselect. 319 * This function is provided by the board code when using a driver 320 * that can't control its chipselects automatically (e.g. 321 * common/soft_spi.c). When called, it should deactivate the chip 322 * select to the device identified by "slave". 323 */ 324 void spi_cs_deactivate(struct spi_slave *slave); 325 326 /** 327 * Set transfer speed. 328 * This sets a new speed to be applied for next spi_xfer(). 329 * @slave: The SPI slave 330 * @hz: The transfer speed 331 */ 332 void spi_set_speed(struct spi_slave *slave, uint hz); 333 #endif 334 335 /** 336 * Write 8 bits, then read 8 bits. 337 * @slave: The SPI slave we're communicating with 338 * @byte: Byte to be written 339 * 340 * Returns: The value that was read, or a negative value on error. 341 * 342 * TODO: This function probably shouldn't be inlined. 343 */ 344 static inline int spi_w8r8(struct spi_slave *slave, unsigned char byte) 345 { 346 unsigned char dout[2]; 347 unsigned char din[2]; 348 int ret; 349 350 dout[0] = byte; 351 dout[1] = 0; 352 353 ret = spi_xfer(slave, 16, dout, din, SPI_XFER_BEGIN | SPI_XFER_END); 354 return ret < 0 ? ret : din[1]; 355 } 356 357 #ifdef CONFIG_DM_SPI 358 359 /** 360 * struct spi_cs_info - Information about a bus chip select 361 * 362 * @dev: Connected device, or NULL if none 363 */ 364 struct spi_cs_info { 365 struct udevice *dev; 366 }; 367 368 /** 369 * struct struct dm_spi_ops - Driver model SPI operations 370 * 371 * The uclass interface is implemented by all SPI devices which use 372 * driver model. 373 */ 374 struct dm_spi_ops { 375 /** 376 * Claim the bus and prepare it for communication. 377 * 378 * The device provided is the slave device. It's parent controller 379 * will be used to provide the communication. 380 * 381 * This must be called before doing any transfers with a SPI slave. It 382 * will enable and initialize any SPI hardware as necessary, and make 383 * sure that the SCK line is in the correct idle state. It is not 384 * allowed to claim the same bus for several slaves without releasing 385 * the bus in between. 386 * 387 * @dev: The SPI slave 388 * 389 * Returns: 0 if the bus was claimed successfully, or a negative value 390 * if it wasn't. 391 */ 392 int (*claim_bus)(struct udevice *dev); 393 394 /** 395 * Release the SPI bus 396 * 397 * This must be called once for every call to spi_claim_bus() after 398 * all transfers have finished. It may disable any SPI hardware as 399 * appropriate. 400 * 401 * @dev: The SPI slave 402 */ 403 int (*release_bus)(struct udevice *dev); 404 405 /** 406 * Set the word length for SPI transactions 407 * 408 * Set the word length (number of bits per word) for SPI transactions. 409 * 410 * @bus: The SPI slave 411 * @wordlen: The number of bits in a word 412 * 413 * Returns: 0 on success, -ve on failure. 414 */ 415 int (*set_wordlen)(struct udevice *dev, unsigned int wordlen); 416 417 /** 418 * SPI transfer 419 * 420 * This writes "bitlen" bits out the SPI MOSI port and simultaneously 421 * clocks "bitlen" bits in the SPI MISO port. That's just the way SPI 422 * works. 423 * 424 * The source of the outgoing bits is the "dout" parameter and the 425 * destination of the input bits is the "din" parameter. Note that 426 * "dout" and "din" can point to the same memory location, in which 427 * case the input data overwrites the output data (since both are 428 * buffered by temporary variables, this is OK). 429 * 430 * spi_xfer() interface: 431 * @dev: The slave device to communicate with 432 * @bitlen: How many bits to write and read. 433 * @dout: Pointer to a string of bits to send out. The bits are 434 * held in a byte array and are sent MSB first. 435 * @din: Pointer to a string of bits that will be filled in. 436 * @flags: A bitwise combination of SPI_XFER_* flags. 437 * 438 * Returns: 0 on success, not -1 on failure 439 */ 440 int (*xfer)(struct udevice *dev, unsigned int bitlen, const void *dout, 441 void *din, unsigned long flags); 442 443 /** 444 * Optimized handlers for SPI memory-like operations. 445 * 446 * Optimized/dedicated operations for interactions with SPI memory. This 447 * field is optional and should only be implemented if the controller 448 * has native support for memory like operations. 449 */ 450 const struct spi_controller_mem_ops *mem_ops; 451 452 /** 453 * Set transfer speed. 454 * This sets a new speed to be applied for next spi_xfer(). 455 * @bus: The SPI bus 456 * @hz: The transfer speed 457 * @return 0 if OK, -ve on error 458 */ 459 int (*set_speed)(struct udevice *bus, uint hz); 460 461 /** 462 * Set the SPI mode/flags 463 * 464 * It is unclear if we want to set speed and mode together instead 465 * of separately. 466 * 467 * @bus: The SPI bus 468 * @mode: Requested SPI mode (SPI_... flags) 469 * @return 0 if OK, -ve on error 470 */ 471 int (*set_mode)(struct udevice *bus, uint mode); 472 473 /** 474 * Get information on a chip select 475 * 476 * This is only called when the SPI uclass does not know about a 477 * chip select, i.e. it has no attached device. It gives the driver 478 * a chance to allow activity on that chip select even so. 479 * 480 * @bus: The SPI bus 481 * @cs: The chip select (0..n-1) 482 * @info: Returns information about the chip select, if valid. 483 * On entry info->dev is NULL 484 * @return 0 if OK (and @info is set up), -ENODEV if the chip select 485 * is invalid, other -ve value on error 486 */ 487 int (*cs_info)(struct udevice *bus, uint cs, struct spi_cs_info *info); 488 489 /** 490 * get_mmap() - Get memory-mapped SPI 491 * 492 * @dev: The SPI flash slave device 493 * @map_basep: Returns base memory address for mapped SPI 494 * @map_sizep: Returns size of mapped SPI 495 * @offsetp: Returns start offset of SPI flash where the map works 496 * correctly (offsets before this are not visible) 497 * @return 0 if OK, -EFAULT if memory mapping is not available 498 */ 499 int (*get_mmap)(struct udevice *dev, ulong *map_basep, 500 uint *map_sizep, uint *offsetp); 501 }; 502 503 struct dm_spi_emul_ops { 504 /** 505 * SPI transfer 506 * 507 * This writes "bitlen" bits out the SPI MOSI port and simultaneously 508 * clocks "bitlen" bits in the SPI MISO port. That's just the way SPI 509 * works. Here the device is a slave. 510 * 511 * The source of the outgoing bits is the "dout" parameter and the 512 * destination of the input bits is the "din" parameter. Note that 513 * "dout" and "din" can point to the same memory location, in which 514 * case the input data overwrites the output data (since both are 515 * buffered by temporary variables, this is OK). 516 * 517 * spi_xfer() interface: 518 * @slave: The SPI slave which will be sending/receiving the data. 519 * @bitlen: How many bits to write and read. 520 * @dout: Pointer to a string of bits sent to the device. The 521 * bits are held in a byte array and are sent MSB first. 522 * @din: Pointer to a string of bits that will be sent back to 523 * the master. 524 * @flags: A bitwise combination of SPI_XFER_* flags. 525 * 526 * Returns: 0 on success, not -1 on failure 527 */ 528 int (*xfer)(struct udevice *slave, unsigned int bitlen, 529 const void *dout, void *din, unsigned long flags); 530 }; 531 532 /** 533 * spi_find_bus_and_cs() - Find bus and slave devices by number 534 * 535 * Given a bus number and chip select, this finds the corresponding bus 536 * device and slave device. Neither device is activated by this function, 537 * although they may have been activated previously. 538 * 539 * @busnum: SPI bus number 540 * @cs: Chip select to look for 541 * @busp: Returns bus device 542 * @devp: Return slave device 543 * @return 0 if found, -ENODEV on error 544 */ 545 int spi_find_bus_and_cs(int busnum, int cs, struct udevice **busp, 546 struct udevice **devp); 547 548 /** 549 * spi_get_bus_and_cs() - Find and activate bus and slave devices by number 550 * 551 * Given a bus number and chip select, this finds the corresponding bus 552 * device and slave device. 553 * 554 * If no such slave exists, and drv_name is not NULL, then a new slave device 555 * is automatically bound on this chip select with requested speed and mode. 556 * 557 * Ths new slave device is probed ready for use with the speed and mode 558 * from platdata when available or the requested values. 559 * 560 * @busnum: SPI bus number 561 * @cs: Chip select to look for 562 * @speed: SPI speed to use for this slave when not available in platdata 563 * @mode: SPI mode to use for this slave when not available in platdata 564 * @drv_name: Name of driver to attach to this chip select 565 * @dev_name: Name of the new device thus created 566 * @busp: Returns bus device 567 * @devp: Return slave device 568 * @return 0 if found, -ve on error 569 */ 570 int spi_get_bus_and_cs(int busnum, int cs, int speed, int mode, 571 const char *drv_name, const char *dev_name, 572 struct udevice **busp, struct spi_slave **devp); 573 574 /** 575 * spi_chip_select() - Get the chip select for a slave 576 * 577 * @return the chip select this slave is attached to 578 */ 579 int spi_chip_select(struct udevice *slave); 580 581 /** 582 * spi_find_chip_select() - Find the slave attached to chip select 583 * 584 * @bus: SPI bus to search 585 * @cs: Chip select to look for 586 * @devp: Returns the slave device if found 587 * @return 0 if found, -EINVAL if cs is invalid, -ENODEV if no device attached, 588 * other -ve value on error 589 */ 590 int spi_find_chip_select(struct udevice *bus, int cs, struct udevice **devp); 591 592 /** 593 * spi_slave_ofdata_to_platdata() - decode standard SPI platform data 594 * 595 * This decodes the speed and mode for a slave from a device tree node 596 * 597 * @blob: Device tree blob 598 * @node: Node offset to read from 599 * @plat: Place to put the decoded information 600 */ 601 int spi_slave_ofdata_to_platdata(struct udevice *dev, 602 struct dm_spi_slave_platdata *plat); 603 604 /** 605 * spi_cs_info() - Check information on a chip select 606 * 607 * This checks a particular chip select on a bus to see if it has a device 608 * attached, or is even valid. 609 * 610 * @bus: The SPI bus 611 * @cs: The chip select (0..n-1) 612 * @info: Returns information about the chip select, if valid 613 * @return 0 if OK (and @info is set up), -ENODEV if the chip select 614 * is invalid, other -ve value on error 615 */ 616 int spi_cs_info(struct udevice *bus, uint cs, struct spi_cs_info *info); 617 618 struct sandbox_state; 619 620 /** 621 * sandbox_spi_get_emul() - get an emulator for a SPI slave 622 * 623 * This provides a way to attach an emulated SPI device to a particular SPI 624 * slave, so that xfer() operations on the slave will be handled by the 625 * emulator. If a emulator already exists on that chip select it is returned. 626 * Otherwise one is created. 627 * 628 * @state: Sandbox state 629 * @bus: SPI bus requesting the emulator 630 * @slave: SPI slave device requesting the emulator 631 * @emuip: Returns pointer to emulator 632 * @return 0 if OK, -ve on error 633 */ 634 int sandbox_spi_get_emul(struct sandbox_state *state, 635 struct udevice *bus, struct udevice *slave, 636 struct udevice **emulp); 637 638 /** 639 * Claim the bus and prepare it for communication with a given slave. 640 * 641 * This must be called before doing any transfers with a SPI slave. It 642 * will enable and initialize any SPI hardware as necessary, and make 643 * sure that the SCK line is in the correct idle state. It is not 644 * allowed to claim the same bus for several slaves without releasing 645 * the bus in between. 646 * 647 * @dev: The SPI slave device 648 * 649 * Returns: 0 if the bus was claimed successfully, or a negative value 650 * if it wasn't. 651 */ 652 int dm_spi_claim_bus(struct udevice *dev); 653 654 /** 655 * Release the SPI bus 656 * 657 * This must be called once for every call to dm_spi_claim_bus() after 658 * all transfers have finished. It may disable any SPI hardware as 659 * appropriate. 660 * 661 * @slave: The SPI slave device 662 */ 663 void dm_spi_release_bus(struct udevice *dev); 664 665 /** 666 * SPI transfer 667 * 668 * This writes "bitlen" bits out the SPI MOSI port and simultaneously clocks 669 * "bitlen" bits in the SPI MISO port. That's just the way SPI works. 670 * 671 * The source of the outgoing bits is the "dout" parameter and the 672 * destination of the input bits is the "din" parameter. Note that "dout" 673 * and "din" can point to the same memory location, in which case the 674 * input data overwrites the output data (since both are buffered by 675 * temporary variables, this is OK). 676 * 677 * dm_spi_xfer() interface: 678 * @dev: The SPI slave device which will be sending/receiving the data. 679 * @bitlen: How many bits to write and read. 680 * @dout: Pointer to a string of bits to send out. The bits are 681 * held in a byte array and are sent MSB first. 682 * @din: Pointer to a string of bits that will be filled in. 683 * @flags: A bitwise combination of SPI_XFER_* flags. 684 * 685 * Returns: 0 on success, not 0 on failure 686 */ 687 int dm_spi_xfer(struct udevice *dev, unsigned int bitlen, 688 const void *dout, void *din, unsigned long flags); 689 690 /** 691 * spi_get_mmap() - Get memory-mapped SPI 692 * 693 * @dev: SPI slave device to check 694 * @map_basep: Returns base memory address for mapped SPI 695 * @map_sizep: Returns size of mapped SPI 696 * @offsetp: Returns start offset of SPI flash where the map works 697 * correctly (offsets before this are not visible) 698 * @return 0 if OK, -ENOSYS if no operation, -EFAULT if memory mapping is not 699 * available 700 */ 701 int dm_spi_get_mmap(struct udevice *dev, ulong *map_basep, uint *map_sizep, 702 uint *offsetp); 703 704 /* Access the operations for a SPI device */ 705 #define spi_get_ops(dev) ((struct dm_spi_ops *)(dev)->driver->ops) 706 #define spi_emul_get_ops(dev) ((struct dm_spi_emul_ops *)(dev)->driver->ops) 707 #endif /* CONFIG_DM_SPI */ 708 709 #endif /* _SPI_H_ */ 710