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 0x01 /* clock phase */ 15 #define SPI_CPOL 0x02 /* 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 0x04 /* CS active high */ 21 #define SPI_LSB_FIRST 0x08 /* per-word bits-on-wire */ 22 #define SPI_3WIRE 0x10 /* SI/SO signals shared */ 23 #define SPI_LOOP 0x20 /* loopback mode */ 24 #define SPI_SLAVE 0x40 /* slave mode */ 25 #define SPI_PREAMBLE 0x80 /* Skip preamble bytes */ 26 27 /* SPI transfer flags */ 28 #define SPI_XFER_BEGIN 0x01 /* Assert CS before transfer */ 29 #define SPI_XFER_END 0x02 /* Deassert CS after transfer */ 30 #define SPI_XFER_MMAP 0x08 /* Memory Mapped start */ 31 #define SPI_XFER_MMAP_END 0x10 /* Memory Mapped End */ 32 #define SPI_XFER_ONCE (SPI_XFER_BEGIN | SPI_XFER_END) 33 #define SPI_XFER_U_PAGE (1 << 5) 34 35 /* SPI TX operation modes */ 36 #define SPI_OPM_TX_QPP (1 << 0) 37 #define SPI_OPM_TX_BP (1 << 1) 38 39 /* SPI RX operation modes */ 40 #define SPI_OPM_RX_AS (1 << 0) 41 #define SPI_OPM_RX_AF (1 << 1) 42 #define SPI_OPM_RX_DOUT (1 << 2) 43 #define SPI_OPM_RX_DIO (1 << 3) 44 #define SPI_OPM_RX_QOF (1 << 4) 45 #define SPI_OPM_RX_QIOF (1 << 5) 46 #define SPI_OPM_RX_EXTN (SPI_OPM_RX_AS | SPI_OPM_RX_AF | SPI_OPM_RX_DOUT | \ 47 SPI_OPM_RX_DIO | SPI_OPM_RX_QOF | \ 48 SPI_OPM_RX_QIOF) 49 50 /* SPI bus connection options - see enum spi_dual_flash */ 51 #define SPI_CONN_DUAL_SHARED (1 << 0) 52 #define SPI_CONN_DUAL_SEPARATED (1 << 1) 53 54 /* Header byte that marks the start of the message */ 55 #define SPI_PREAMBLE_END_BYTE 0xec 56 57 #define SPI_DEFAULT_WORDLEN 8 58 59 #ifdef CONFIG_DM_SPI 60 /* TODO(sjg@chromium.org): Remove this and use max_hz from struct spi_slave */ 61 struct dm_spi_bus { 62 uint max_hz; 63 }; 64 65 /** 66 * struct dm_spi_platdata - platform data for all SPI slaves 67 * 68 * This describes a SPI slave, a child device of the SPI bus. To obtain this 69 * struct from a spi_slave, use dev_get_parent_platdata(dev) or 70 * dev_get_parent_platdata(slave->dev). 71 * 72 * This data is immuatable. Each time the device is probed, @max_hz and @mode 73 * will be copied to struct spi_slave. 74 * 75 * @cs: Chip select number (0..n-1) 76 * @max_hz: Maximum bus speed that this slave can tolerate 77 * @mode: SPI mode to use for this device (see SPI mode flags) 78 */ 79 struct dm_spi_slave_platdata { 80 unsigned int cs; 81 uint max_hz; 82 uint mode; 83 }; 84 85 #endif /* CONFIG_DM_SPI */ 86 87 /** 88 * struct spi_slave - Representation of a SPI slave 89 * 90 * For driver model this is the per-child data used by the SPI bus. It can 91 * be accessed using dev_get_parentdata() on the slave device. The SPI uclass 92 * sets uip per_child_auto_alloc_size to sizeof(struct spi_slave), and the 93 * driver should not override it. Two platform data fields (max_hz and mode) 94 * are copied into this structure to provide an initial value. This allows 95 * them to be changed, since we should never change platform data in drivers. 96 * 97 * If not using driver model, drivers are expected to extend this with 98 * controller-specific data. 99 * 100 * @dev: SPI slave device 101 * @max_hz: Maximum speed for this slave 102 * @mode: SPI mode to use for this slave (see SPI mode flags) 103 * @bus: ID of the bus that the slave is attached to. For 104 * driver model this is the sequence number of the SPI 105 * bus (bus->seq) so does not need to be stored 106 * @cs: ID of the chip select connected to the slave. 107 * @op_mode_rx: SPI RX operation mode. 108 * @op_mode_tx: SPI TX operation mode. 109 * @wordlen: Size of SPI word in number of bits 110 * @max_write_size: If non-zero, the maximum number of bytes which can 111 * be written at once, excluding command bytes. 112 * @memory_map: Address of read-only SPI flash access. 113 * @option: Varies SPI bus options - separate, shared bus. 114 * @flags: Indication of SPI flags. 115 */ 116 struct spi_slave { 117 #ifdef CONFIG_DM_SPI 118 struct udevice *dev; /* struct spi_slave is dev->parentdata */ 119 uint max_hz; 120 uint mode; 121 #else 122 unsigned int bus; 123 unsigned int cs; 124 #endif 125 u8 op_mode_rx; 126 u8 op_mode_tx; 127 unsigned int wordlen; 128 unsigned int max_write_size; 129 void *memory_map; 130 u8 option; 131 u8 flags; 132 }; 133 134 /** 135 * Initialization, must be called once on start up. 136 * 137 * TODO: I don't think we really need this. 138 */ 139 void spi_init(void); 140 141 /** 142 * spi_do_alloc_slave - Allocate a new SPI slave (internal) 143 * 144 * Allocate and zero all fields in the spi slave, and set the bus/chip 145 * select. Use the helper macro spi_alloc_slave() to call this. 146 * 147 * @offset: Offset of struct spi_slave within slave structure. 148 * @size: Size of slave structure. 149 * @bus: Bus ID of the slave chip. 150 * @cs: Chip select ID of the slave chip on the specified bus. 151 */ 152 void *spi_do_alloc_slave(int offset, int size, unsigned int bus, 153 unsigned int cs); 154 155 /** 156 * spi_alloc_slave - Allocate a new SPI slave 157 * 158 * Allocate and zero all fields in the spi slave, and set the bus/chip 159 * select. 160 * 161 * @_struct: Name of structure to allocate (e.g. struct tegra_spi). 162 * This structure must contain a member 'struct spi_slave *slave'. 163 * @bus: Bus ID of the slave chip. 164 * @cs: Chip select ID of the slave chip on the specified bus. 165 */ 166 #define spi_alloc_slave(_struct, bus, cs) \ 167 spi_do_alloc_slave(offsetof(_struct, slave), \ 168 sizeof(_struct), bus, cs) 169 170 /** 171 * spi_alloc_slave_base - Allocate a new SPI slave with no private data 172 * 173 * Allocate and zero all fields in the spi slave, and set the bus/chip 174 * select. 175 * 176 * @bus: Bus ID of the slave chip. 177 * @cs: Chip select ID of the slave chip on the specified bus. 178 */ 179 #define spi_alloc_slave_base(bus, cs) \ 180 spi_do_alloc_slave(0, sizeof(struct spi_slave), bus, cs) 181 182 /** 183 * Set up communications parameters for a SPI slave. 184 * 185 * This must be called once for each slave. Note that this function 186 * usually doesn't touch any actual hardware, it only initializes the 187 * contents of spi_slave so that the hardware can be easily 188 * initialized later. 189 * 190 * @bus: Bus ID of the slave chip. 191 * @cs: Chip select ID of the slave chip on the specified bus. 192 * @max_hz: Maximum SCK rate in Hz. 193 * @mode: Clock polarity, clock phase and other parameters. 194 * 195 * Returns: A spi_slave reference that can be used in subsequent SPI 196 * calls, or NULL if one or more of the parameters are not supported. 197 */ 198 struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs, 199 unsigned int max_hz, unsigned int mode); 200 201 /** 202 * Free any memory associated with a SPI slave. 203 * 204 * @slave: The SPI slave 205 */ 206 void spi_free_slave(struct spi_slave *slave); 207 208 /** 209 * Claim the bus and prepare it for communication with a given slave. 210 * 211 * This must be called before doing any transfers with a SPI slave. It 212 * will enable and initialize any SPI hardware as necessary, and make 213 * sure that the SCK line is in the correct idle state. It is not 214 * allowed to claim the same bus for several slaves without releasing 215 * the bus in between. 216 * 217 * @slave: The SPI slave 218 * 219 * Returns: 0 if the bus was claimed successfully, or a negative value 220 * if it wasn't. 221 */ 222 int spi_claim_bus(struct spi_slave *slave); 223 224 /** 225 * Release the SPI bus 226 * 227 * This must be called once for every call to spi_claim_bus() after 228 * all transfers have finished. It may disable any SPI hardware as 229 * appropriate. 230 * 231 * @slave: The SPI slave 232 */ 233 void spi_release_bus(struct spi_slave *slave); 234 235 /** 236 * Set the word length for SPI transactions 237 * 238 * Set the word length (number of bits per word) for SPI transactions. 239 * 240 * @slave: The SPI slave 241 * @wordlen: The number of bits in a word 242 * 243 * Returns: 0 on success, -1 on failure. 244 */ 245 int spi_set_wordlen(struct spi_slave *slave, unsigned int wordlen); 246 247 /** 248 * SPI transfer 249 * 250 * This writes "bitlen" bits out the SPI MOSI port and simultaneously clocks 251 * "bitlen" bits in the SPI MISO port. That's just the way SPI works. 252 * 253 * The source of the outgoing bits is the "dout" parameter and the 254 * destination of the input bits is the "din" parameter. Note that "dout" 255 * and "din" can point to the same memory location, in which case the 256 * input data overwrites the output data (since both are buffered by 257 * temporary variables, this is OK). 258 * 259 * spi_xfer() interface: 260 * @slave: The SPI slave which will be sending/receiving the data. 261 * @bitlen: How many bits to write and read. 262 * @dout: Pointer to a string of bits to send out. The bits are 263 * held in a byte array and are sent MSB first. 264 * @din: Pointer to a string of bits that will be filled in. 265 * @flags: A bitwise combination of SPI_XFER_* flags. 266 * 267 * Returns: 0 on success, not 0 on failure 268 */ 269 int spi_xfer(struct spi_slave *slave, unsigned int bitlen, const void *dout, 270 void *din, unsigned long flags); 271 272 /** 273 * Determine if a SPI chipselect is valid. 274 * This function is provided by the board if the low-level SPI driver 275 * needs it to determine if a given chipselect is actually valid. 276 * 277 * Returns: 1 if bus:cs identifies a valid chip on this board, 0 278 * otherwise. 279 */ 280 int spi_cs_is_valid(unsigned int bus, unsigned int cs); 281 282 #ifndef CONFIG_DM_SPI 283 /** 284 * Activate a SPI chipselect. 285 * This function is provided by the board code when using a driver 286 * that can't control its chipselects automatically (e.g. 287 * common/soft_spi.c). When called, it should activate the chip select 288 * to the device identified by "slave". 289 */ 290 void spi_cs_activate(struct spi_slave *slave); 291 292 /** 293 * Deactivate a SPI chipselect. 294 * This function is provided by the board code when using a driver 295 * that can't control its chipselects automatically (e.g. 296 * common/soft_spi.c). When called, it should deactivate the chip 297 * select to the device identified by "slave". 298 */ 299 void spi_cs_deactivate(struct spi_slave *slave); 300 301 /** 302 * Set transfer speed. 303 * This sets a new speed to be applied for next spi_xfer(). 304 * @slave: The SPI slave 305 * @hz: The transfer speed 306 */ 307 void spi_set_speed(struct spi_slave *slave, uint hz); 308 #endif 309 310 /** 311 * Write 8 bits, then read 8 bits. 312 * @slave: The SPI slave we're communicating with 313 * @byte: Byte to be written 314 * 315 * Returns: The value that was read, or a negative value on error. 316 * 317 * TODO: This function probably shouldn't be inlined. 318 */ 319 static inline int spi_w8r8(struct spi_slave *slave, unsigned char byte) 320 { 321 unsigned char dout[2]; 322 unsigned char din[2]; 323 int ret; 324 325 dout[0] = byte; 326 dout[1] = 0; 327 328 ret = spi_xfer(slave, 16, dout, din, SPI_XFER_BEGIN | SPI_XFER_END); 329 return ret < 0 ? ret : din[1]; 330 } 331 332 /** 333 * Set up a SPI slave for a particular device tree node 334 * 335 * This calls spi_setup_slave() with the correct bus number. Call 336 * spi_free_slave() to free it later. 337 * 338 * @param blob: Device tree blob 339 * @param slave_node: Slave node to use 340 * @param spi_node: SPI peripheral node to use 341 * @return pointer to new spi_slave structure 342 */ 343 struct spi_slave *spi_setup_slave_fdt(const void *blob, int slave_node, 344 int spi_node); 345 346 /** 347 * spi_base_setup_slave_fdt() - helper function to set up a SPI slace 348 * 349 * This decodes SPI properties from the slave node to determine the 350 * chip select and SPI parameters. 351 * 352 * @blob: Device tree blob 353 * @busnum: Bus number to use 354 * @node: Device tree node for the SPI bus 355 */ 356 struct spi_slave *spi_base_setup_slave_fdt(const void *blob, int busnum, 357 int node); 358 359 #ifdef CONFIG_DM_SPI 360 361 /** 362 * struct spi_cs_info - Information about a bus chip select 363 * 364 * @dev: Connected device, or NULL if none 365 */ 366 struct spi_cs_info { 367 struct udevice *dev; 368 }; 369 370 /** 371 * struct struct dm_spi_ops - Driver model SPI operations 372 * 373 * The uclass interface is implemented by all SPI devices which use 374 * driver model. 375 */ 376 struct dm_spi_ops { 377 /** 378 * Claim the bus and prepare it for communication. 379 * 380 * The device provided is the slave device. It's parent controller 381 * will be used to provide the communication. 382 * 383 * This must be called before doing any transfers with a SPI slave. It 384 * will enable and initialize any SPI hardware as necessary, and make 385 * sure that the SCK line is in the correct idle state. It is not 386 * allowed to claim the same bus for several slaves without releasing 387 * the bus in between. 388 * 389 * @dev: The SPI slave 390 * 391 * Returns: 0 if the bus was claimed successfully, or a negative value 392 * if it wasn't. 393 */ 394 int (*claim_bus)(struct udevice *dev); 395 396 /** 397 * Release the SPI bus 398 * 399 * This must be called once for every call to spi_claim_bus() after 400 * all transfers have finished. It may disable any SPI hardware as 401 * appropriate. 402 * 403 * @dev: The SPI slave 404 */ 405 int (*release_bus)(struct udevice *dev); 406 407 /** 408 * Set the word length for SPI transactions 409 * 410 * Set the word length (number of bits per word) for SPI transactions. 411 * 412 * @bus: The SPI slave 413 * @wordlen: The number of bits in a word 414 * 415 * Returns: 0 on success, -ve on failure. 416 */ 417 int (*set_wordlen)(struct udevice *dev, unsigned int wordlen); 418 419 /** 420 * SPI transfer 421 * 422 * This writes "bitlen" bits out the SPI MOSI port and simultaneously 423 * clocks "bitlen" bits in the SPI MISO port. That's just the way SPI 424 * works. 425 * 426 * The source of the outgoing bits is the "dout" parameter and the 427 * destination of the input bits is the "din" parameter. Note that 428 * "dout" and "din" can point to the same memory location, in which 429 * case the input data overwrites the output data (since both are 430 * buffered by temporary variables, this is OK). 431 * 432 * spi_xfer() interface: 433 * @dev: The slave device to communicate with 434 * @bitlen: How many bits to write and read. 435 * @dout: Pointer to a string of bits to send out. The bits are 436 * held in a byte array and are sent MSB first. 437 * @din: Pointer to a string of bits that will be filled in. 438 * @flags: A bitwise combination of SPI_XFER_* flags. 439 * 440 * Returns: 0 on success, not -1 on failure 441 */ 442 int (*xfer)(struct udevice *dev, unsigned int bitlen, const void *dout, 443 void *din, unsigned long flags); 444 445 /** 446 * Set transfer speed. 447 * This sets a new speed to be applied for next spi_xfer(). 448 * @bus: The SPI bus 449 * @hz: The transfer speed 450 * @return 0 if OK, -ve on error 451 */ 452 int (*set_speed)(struct udevice *bus, uint hz); 453 454 /** 455 * Set the SPI mode/flags 456 * 457 * It is unclear if we want to set speed and mode together instead 458 * of separately. 459 * 460 * @bus: The SPI bus 461 * @mode: Requested SPI mode (SPI_... flags) 462 * @return 0 if OK, -ve on error 463 */ 464 int (*set_mode)(struct udevice *bus, uint mode); 465 466 /** 467 * Get information on a chip select 468 * 469 * This is only called when the SPI uclass does not know about a 470 * chip select, i.e. it has no attached device. It gives the driver 471 * a chance to allow activity on that chip select even so. 472 * 473 * @bus: The SPI bus 474 * @cs: The chip select (0..n-1) 475 * @info: Returns information about the chip select, if valid. 476 * On entry info->dev is NULL 477 * @return 0 if OK (and @info is set up), -ENODEV if the chip select 478 * is invalid, other -ve value on error 479 */ 480 int (*cs_info)(struct udevice *bus, uint cs, struct spi_cs_info *info); 481 }; 482 483 struct dm_spi_emul_ops { 484 /** 485 * SPI transfer 486 * 487 * This writes "bitlen" bits out the SPI MOSI port and simultaneously 488 * clocks "bitlen" bits in the SPI MISO port. That's just the way SPI 489 * works. Here the device is a slave. 490 * 491 * The source of the outgoing bits is the "dout" parameter and the 492 * destination of the input bits is the "din" parameter. Note that 493 * "dout" and "din" can point to the same memory location, in which 494 * case the input data overwrites the output data (since both are 495 * buffered by temporary variables, this is OK). 496 * 497 * spi_xfer() interface: 498 * @slave: The SPI slave which will be sending/receiving the data. 499 * @bitlen: How many bits to write and read. 500 * @dout: Pointer to a string of bits sent to the device. The 501 * bits are held in a byte array and are sent MSB first. 502 * @din: Pointer to a string of bits that will be sent back to 503 * the master. 504 * @flags: A bitwise combination of SPI_XFER_* flags. 505 * 506 * Returns: 0 on success, not -1 on failure 507 */ 508 int (*xfer)(struct udevice *slave, unsigned int bitlen, 509 const void *dout, void *din, unsigned long flags); 510 }; 511 512 /** 513 * spi_find_bus_and_cs() - Find bus and slave devices by number 514 * 515 * Given a bus number and chip select, this finds the corresponding bus 516 * device and slave device. Neither device is activated by this function, 517 * although they may have been activated previously. 518 * 519 * @busnum: SPI bus number 520 * @cs: Chip select to look for 521 * @busp: Returns bus device 522 * @devp: Return slave device 523 * @return 0 if found, -ENODEV on error 524 */ 525 int spi_find_bus_and_cs(int busnum, int cs, struct udevice **busp, 526 struct udevice **devp); 527 528 /** 529 * spi_get_bus_and_cs() - Find and activate bus and slave devices by number 530 * 531 * Given a bus number and chip select, this finds the corresponding bus 532 * device and slave device. 533 * 534 * If no such slave exists, and drv_name is not NULL, then a new slave device 535 * is automatically bound on this chip select. 536 * 537 * Ths new slave device is probed ready for use with the given speed and mode. 538 * 539 * @busnum: SPI bus number 540 * @cs: Chip select to look for 541 * @speed: SPI speed to use for this slave 542 * @mode: SPI mode to use for this slave 543 * @drv_name: Name of driver to attach to this chip select 544 * @dev_name: Name of the new device thus created 545 * @busp: Returns bus device 546 * @devp: Return slave device 547 * @return 0 if found, -ve on error 548 */ 549 int spi_get_bus_and_cs(int busnum, int cs, int speed, int mode, 550 const char *drv_name, const char *dev_name, 551 struct udevice **busp, struct spi_slave **devp); 552 553 /** 554 * spi_chip_select() - Get the chip select for a slave 555 * 556 * @return the chip select this slave is attached to 557 */ 558 int spi_chip_select(struct udevice *slave); 559 560 /** 561 * spi_find_chip_select() - Find the slave attached to chip select 562 * 563 * @bus: SPI bus to search 564 * @cs: Chip select to look for 565 * @devp: Returns the slave device if found 566 * @return 0 if found, -ENODEV on error 567 */ 568 int spi_find_chip_select(struct udevice *bus, int cs, struct udevice **devp); 569 570 /** 571 * spi_slave_ofdata_to_platdata() - decode standard SPI platform data 572 * 573 * This decodes the speed and mode for a slave from a device tree node 574 * 575 * @blob: Device tree blob 576 * @node: Node offset to read from 577 * @plat: Place to put the decoded information 578 */ 579 int spi_slave_ofdata_to_platdata(const void *blob, int node, 580 struct dm_spi_slave_platdata *plat); 581 582 /** 583 * spi_cs_info() - Check information on a chip select 584 * 585 * This checks a particular chip select on a bus to see if it has a device 586 * attached, or is even valid. 587 * 588 * @bus: The SPI bus 589 * @cs: The chip select (0..n-1) 590 * @info: Returns information about the chip select, if valid 591 * @return 0 if OK (and @info is set up), -ENODEV if the chip select 592 * is invalid, other -ve value on error 593 */ 594 int spi_cs_info(struct udevice *bus, uint cs, struct spi_cs_info *info); 595 596 struct sandbox_state; 597 598 /** 599 * sandbox_spi_get_emul() - get an emulator for a SPI slave 600 * 601 * This provides a way to attach an emulated SPI device to a particular SPI 602 * slave, so that xfer() operations on the slave will be handled by the 603 * emulator. If a emulator already exists on that chip select it is returned. 604 * Otherwise one is created. 605 * 606 * @state: Sandbox state 607 * @bus: SPI bus requesting the emulator 608 * @slave: SPI slave device requesting the emulator 609 * @emuip: Returns pointer to emulator 610 * @return 0 if OK, -ve on error 611 */ 612 int sandbox_spi_get_emul(struct sandbox_state *state, 613 struct udevice *bus, struct udevice *slave, 614 struct udevice **emulp); 615 616 /* Access the serial operations for a device */ 617 #define spi_get_ops(dev) ((struct dm_spi_ops *)(dev)->driver->ops) 618 #define spi_emul_get_ops(dev) ((struct dm_spi_emul_ops *)(dev)->driver->ops) 619 #endif /* CONFIG_DM_SPI */ 620 621 #endif /* _SPI_H_ */ 622