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 * @speed: Current bus speed. This is 0 until the bus is first 104 * claimed. 105 * @bus: ID of the bus that the slave is attached to. For 106 * driver model this is the sequence number of the SPI 107 * bus (bus->seq) so does not need to be stored 108 * @cs: ID of the chip select connected to the slave. 109 * @op_mode_rx: SPI RX operation mode. 110 * @op_mode_tx: SPI TX operation mode. 111 * @wordlen: Size of SPI word in number of bits 112 * @max_write_size: If non-zero, the maximum number of bytes which can 113 * be written at once, excluding command bytes. 114 * @memory_map: Address of read-only SPI flash access. 115 * @option: Varies SPI bus options - separate, shared bus. 116 * @flags: Indication of SPI flags. 117 */ 118 struct spi_slave { 119 #ifdef CONFIG_DM_SPI 120 struct udevice *dev; /* struct spi_slave is dev->parentdata */ 121 uint max_hz; 122 uint speed; 123 uint mode; 124 #else 125 unsigned int bus; 126 unsigned int cs; 127 #endif 128 u8 op_mode_rx; 129 u8 op_mode_tx; 130 unsigned int wordlen; 131 unsigned int max_write_size; 132 void *memory_map; 133 u8 option; 134 u8 flags; 135 }; 136 137 /** 138 * Initialization, must be called once on start up. 139 * 140 * TODO: I don't think we really need this. 141 */ 142 void spi_init(void); 143 144 /** 145 * spi_do_alloc_slave - Allocate a new SPI slave (internal) 146 * 147 * Allocate and zero all fields in the spi slave, and set the bus/chip 148 * select. Use the helper macro spi_alloc_slave() to call this. 149 * 150 * @offset: Offset of struct spi_slave within slave structure. 151 * @size: Size of slave structure. 152 * @bus: Bus ID of the slave chip. 153 * @cs: Chip select ID of the slave chip on the specified bus. 154 */ 155 void *spi_do_alloc_slave(int offset, int size, unsigned int bus, 156 unsigned int cs); 157 158 /** 159 * spi_alloc_slave - Allocate a new SPI slave 160 * 161 * Allocate and zero all fields in the spi slave, and set the bus/chip 162 * select. 163 * 164 * @_struct: Name of structure to allocate (e.g. struct tegra_spi). 165 * This structure must contain a member 'struct spi_slave *slave'. 166 * @bus: Bus ID of the slave chip. 167 * @cs: Chip select ID of the slave chip on the specified bus. 168 */ 169 #define spi_alloc_slave(_struct, bus, cs) \ 170 spi_do_alloc_slave(offsetof(_struct, slave), \ 171 sizeof(_struct), bus, cs) 172 173 /** 174 * spi_alloc_slave_base - Allocate a new SPI slave with no private data 175 * 176 * Allocate and zero all fields in the spi slave, and set the bus/chip 177 * select. 178 * 179 * @bus: Bus ID of the slave chip. 180 * @cs: Chip select ID of the slave chip on the specified bus. 181 */ 182 #define spi_alloc_slave_base(bus, cs) \ 183 spi_do_alloc_slave(0, sizeof(struct spi_slave), bus, cs) 184 185 /** 186 * Set up communications parameters for a SPI slave. 187 * 188 * This must be called once for each slave. Note that this function 189 * usually doesn't touch any actual hardware, it only initializes the 190 * contents of spi_slave so that the hardware can be easily 191 * initialized later. 192 * 193 * @bus: Bus ID of the slave chip. 194 * @cs: Chip select ID of the slave chip on the specified bus. 195 * @max_hz: Maximum SCK rate in Hz. 196 * @mode: Clock polarity, clock phase and other parameters. 197 * 198 * Returns: A spi_slave reference that can be used in subsequent SPI 199 * calls, or NULL if one or more of the parameters are not supported. 200 */ 201 struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs, 202 unsigned int max_hz, unsigned int mode); 203 204 /** 205 * Free any memory associated with a SPI slave. 206 * 207 * @slave: The SPI slave 208 */ 209 void spi_free_slave(struct spi_slave *slave); 210 211 /** 212 * Claim the bus and prepare it for communication with a given slave. 213 * 214 * This must be called before doing any transfers with a SPI slave. It 215 * will enable and initialize any SPI hardware as necessary, and make 216 * sure that the SCK line is in the correct idle state. It is not 217 * allowed to claim the same bus for several slaves without releasing 218 * the bus in between. 219 * 220 * @slave: The SPI slave 221 * 222 * Returns: 0 if the bus was claimed successfully, or a negative value 223 * if it wasn't. 224 */ 225 int spi_claim_bus(struct spi_slave *slave); 226 227 /** 228 * Release the SPI bus 229 * 230 * This must be called once for every call to spi_claim_bus() after 231 * all transfers have finished. It may disable any SPI hardware as 232 * appropriate. 233 * 234 * @slave: The SPI slave 235 */ 236 void spi_release_bus(struct spi_slave *slave); 237 238 /** 239 * Set the word length for SPI transactions 240 * 241 * Set the word length (number of bits per word) for SPI transactions. 242 * 243 * @slave: The SPI slave 244 * @wordlen: The number of bits in a word 245 * 246 * Returns: 0 on success, -1 on failure. 247 */ 248 int spi_set_wordlen(struct spi_slave *slave, unsigned int wordlen); 249 250 /** 251 * SPI transfer 252 * 253 * This writes "bitlen" bits out the SPI MOSI port and simultaneously clocks 254 * "bitlen" bits in the SPI MISO port. That's just the way SPI works. 255 * 256 * The source of the outgoing bits is the "dout" parameter and the 257 * destination of the input bits is the "din" parameter. Note that "dout" 258 * and "din" can point to the same memory location, in which case the 259 * input data overwrites the output data (since both are buffered by 260 * temporary variables, this is OK). 261 * 262 * spi_xfer() interface: 263 * @slave: The SPI slave which will be sending/receiving the data. 264 * @bitlen: How many bits to write and read. 265 * @dout: Pointer to a string of bits to send out. The bits are 266 * held in a byte array and are sent MSB first. 267 * @din: Pointer to a string of bits that will be filled in. 268 * @flags: A bitwise combination of SPI_XFER_* flags. 269 * 270 * Returns: 0 on success, not 0 on failure 271 */ 272 int spi_xfer(struct spi_slave *slave, unsigned int bitlen, const void *dout, 273 void *din, unsigned long flags); 274 275 /** 276 * Determine if a SPI chipselect is valid. 277 * This function is provided by the board if the low-level SPI driver 278 * needs it to determine if a given chipselect is actually valid. 279 * 280 * Returns: 1 if bus:cs identifies a valid chip on this board, 0 281 * otherwise. 282 */ 283 int spi_cs_is_valid(unsigned int bus, unsigned int cs); 284 285 #ifndef CONFIG_DM_SPI 286 /** 287 * Activate a SPI chipselect. 288 * This function is provided by the board code when using a driver 289 * that can't control its chipselects automatically (e.g. 290 * common/soft_spi.c). When called, it should activate the chip select 291 * to the device identified by "slave". 292 */ 293 void spi_cs_activate(struct spi_slave *slave); 294 295 /** 296 * Deactivate a SPI chipselect. 297 * This function is provided by the board code when using a driver 298 * that can't control its chipselects automatically (e.g. 299 * common/soft_spi.c). When called, it should deactivate the chip 300 * select to the device identified by "slave". 301 */ 302 void spi_cs_deactivate(struct spi_slave *slave); 303 304 /** 305 * Set transfer speed. 306 * This sets a new speed to be applied for next spi_xfer(). 307 * @slave: The SPI slave 308 * @hz: The transfer speed 309 */ 310 void spi_set_speed(struct spi_slave *slave, uint hz); 311 #endif 312 313 /** 314 * Write 8 bits, then read 8 bits. 315 * @slave: The SPI slave we're communicating with 316 * @byte: Byte to be written 317 * 318 * Returns: The value that was read, or a negative value on error. 319 * 320 * TODO: This function probably shouldn't be inlined. 321 */ 322 static inline int spi_w8r8(struct spi_slave *slave, unsigned char byte) 323 { 324 unsigned char dout[2]; 325 unsigned char din[2]; 326 int ret; 327 328 dout[0] = byte; 329 dout[1] = 0; 330 331 ret = spi_xfer(slave, 16, dout, din, SPI_XFER_BEGIN | SPI_XFER_END); 332 return ret < 0 ? ret : din[1]; 333 } 334 335 /** 336 * Set up a SPI slave for a particular device tree node 337 * 338 * This calls spi_setup_slave() with the correct bus number. Call 339 * spi_free_slave() to free it later. 340 * 341 * @param blob: Device tree blob 342 * @param slave_node: Slave node to use 343 * @param spi_node: SPI peripheral node to use 344 * @return pointer to new spi_slave structure 345 */ 346 struct spi_slave *spi_setup_slave_fdt(const void *blob, int slave_node, 347 int spi_node); 348 349 /** 350 * spi_base_setup_slave_fdt() - helper function to set up a SPI slace 351 * 352 * This decodes SPI properties from the slave node to determine the 353 * chip select and SPI parameters. 354 * 355 * @blob: Device tree blob 356 * @busnum: Bus number to use 357 * @node: Device tree node for the SPI bus 358 */ 359 struct spi_slave *spi_base_setup_slave_fdt(const void *blob, int busnum, 360 int node); 361 362 #ifdef CONFIG_DM_SPI 363 364 /** 365 * struct spi_cs_info - Information about a bus chip select 366 * 367 * @dev: Connected device, or NULL if none 368 */ 369 struct spi_cs_info { 370 struct udevice *dev; 371 }; 372 373 /** 374 * struct struct dm_spi_ops - Driver model SPI operations 375 * 376 * The uclass interface is implemented by all SPI devices which use 377 * driver model. 378 */ 379 struct dm_spi_ops { 380 /** 381 * Claim the bus and prepare it for communication. 382 * 383 * The device provided is the slave device. It's parent controller 384 * will be used to provide the communication. 385 * 386 * This must be called before doing any transfers with a SPI slave. It 387 * will enable and initialize any SPI hardware as necessary, and make 388 * sure that the SCK line is in the correct idle state. It is not 389 * allowed to claim the same bus for several slaves without releasing 390 * the bus in between. 391 * 392 * @dev: The SPI slave 393 * 394 * Returns: 0 if the bus was claimed successfully, or a negative value 395 * if it wasn't. 396 */ 397 int (*claim_bus)(struct udevice *dev); 398 399 /** 400 * Release the SPI bus 401 * 402 * This must be called once for every call to spi_claim_bus() after 403 * all transfers have finished. It may disable any SPI hardware as 404 * appropriate. 405 * 406 * @dev: The SPI slave 407 */ 408 int (*release_bus)(struct udevice *dev); 409 410 /** 411 * Set the word length for SPI transactions 412 * 413 * Set the word length (number of bits per word) for SPI transactions. 414 * 415 * @bus: The SPI slave 416 * @wordlen: The number of bits in a word 417 * 418 * Returns: 0 on success, -ve on failure. 419 */ 420 int (*set_wordlen)(struct udevice *dev, unsigned int wordlen); 421 422 /** 423 * SPI transfer 424 * 425 * This writes "bitlen" bits out the SPI MOSI port and simultaneously 426 * clocks "bitlen" bits in the SPI MISO port. That's just the way SPI 427 * works. 428 * 429 * The source of the outgoing bits is the "dout" parameter and the 430 * destination of the input bits is the "din" parameter. Note that 431 * "dout" and "din" can point to the same memory location, in which 432 * case the input data overwrites the output data (since both are 433 * buffered by temporary variables, this is OK). 434 * 435 * spi_xfer() interface: 436 * @dev: The slave device to communicate with 437 * @bitlen: How many bits to write and read. 438 * @dout: Pointer to a string of bits to send out. The bits are 439 * held in a byte array and are sent MSB first. 440 * @din: Pointer to a string of bits that will be filled in. 441 * @flags: A bitwise combination of SPI_XFER_* flags. 442 * 443 * Returns: 0 on success, not -1 on failure 444 */ 445 int (*xfer)(struct udevice *dev, unsigned int bitlen, const void *dout, 446 void *din, unsigned long flags); 447 448 /** 449 * Set transfer speed. 450 * This sets a new speed to be applied for next spi_xfer(). 451 * @bus: The SPI bus 452 * @hz: The transfer speed 453 * @return 0 if OK, -ve on error 454 */ 455 int (*set_speed)(struct udevice *bus, uint hz); 456 457 /** 458 * Set the SPI mode/flags 459 * 460 * It is unclear if we want to set speed and mode together instead 461 * of separately. 462 * 463 * @bus: The SPI bus 464 * @mode: Requested SPI mode (SPI_... flags) 465 * @return 0 if OK, -ve on error 466 */ 467 int (*set_mode)(struct udevice *bus, uint mode); 468 469 /** 470 * Get information on a chip select 471 * 472 * This is only called when the SPI uclass does not know about a 473 * chip select, i.e. it has no attached device. It gives the driver 474 * a chance to allow activity on that chip select even so. 475 * 476 * @bus: The SPI bus 477 * @cs: The chip select (0..n-1) 478 * @info: Returns information about the chip select, if valid. 479 * On entry info->dev is NULL 480 * @return 0 if OK (and @info is set up), -ENODEV if the chip select 481 * is invalid, other -ve value on error 482 */ 483 int (*cs_info)(struct udevice *bus, uint cs, struct spi_cs_info *info); 484 }; 485 486 struct dm_spi_emul_ops { 487 /** 488 * SPI transfer 489 * 490 * This writes "bitlen" bits out the SPI MOSI port and simultaneously 491 * clocks "bitlen" bits in the SPI MISO port. That's just the way SPI 492 * works. Here the device is a slave. 493 * 494 * The source of the outgoing bits is the "dout" parameter and the 495 * destination of the input bits is the "din" parameter. Note that 496 * "dout" and "din" can point to the same memory location, in which 497 * case the input data overwrites the output data (since both are 498 * buffered by temporary variables, this is OK). 499 * 500 * spi_xfer() interface: 501 * @slave: The SPI slave which will be sending/receiving the data. 502 * @bitlen: How many bits to write and read. 503 * @dout: Pointer to a string of bits sent to the device. The 504 * bits are held in a byte array and are sent MSB first. 505 * @din: Pointer to a string of bits that will be sent back to 506 * the master. 507 * @flags: A bitwise combination of SPI_XFER_* flags. 508 * 509 * Returns: 0 on success, not -1 on failure 510 */ 511 int (*xfer)(struct udevice *slave, unsigned int bitlen, 512 const void *dout, void *din, unsigned long flags); 513 }; 514 515 /** 516 * spi_find_bus_and_cs() - Find bus and slave devices by number 517 * 518 * Given a bus number and chip select, this finds the corresponding bus 519 * device and slave device. Neither device is activated by this function, 520 * although they may have been activated previously. 521 * 522 * @busnum: SPI bus number 523 * @cs: Chip select to look for 524 * @busp: Returns bus device 525 * @devp: Return slave device 526 * @return 0 if found, -ENODEV on error 527 */ 528 int spi_find_bus_and_cs(int busnum, int cs, struct udevice **busp, 529 struct udevice **devp); 530 531 /** 532 * spi_get_bus_and_cs() - Find and activate bus and slave devices by number 533 * 534 * Given a bus number and chip select, this finds the corresponding bus 535 * device and slave device. 536 * 537 * If no such slave exists, and drv_name is not NULL, then a new slave device 538 * is automatically bound on this chip select. 539 * 540 * Ths new slave device is probed ready for use with the given speed and mode. 541 * 542 * @busnum: SPI bus number 543 * @cs: Chip select to look for 544 * @speed: SPI speed to use for this slave 545 * @mode: SPI mode to use for this slave 546 * @drv_name: Name of driver to attach to this chip select 547 * @dev_name: Name of the new device thus created 548 * @busp: Returns bus device 549 * @devp: Return slave device 550 * @return 0 if found, -ve on error 551 */ 552 int spi_get_bus_and_cs(int busnum, int cs, int speed, int mode, 553 const char *drv_name, const char *dev_name, 554 struct udevice **busp, struct spi_slave **devp); 555 556 /** 557 * spi_chip_select() - Get the chip select for a slave 558 * 559 * @return the chip select this slave is attached to 560 */ 561 int spi_chip_select(struct udevice *slave); 562 563 /** 564 * spi_find_chip_select() - Find the slave attached to chip select 565 * 566 * @bus: SPI bus to search 567 * @cs: Chip select to look for 568 * @devp: Returns the slave device if found 569 * @return 0 if found, -ENODEV on error 570 */ 571 int spi_find_chip_select(struct udevice *bus, int cs, struct udevice **devp); 572 573 /** 574 * spi_slave_ofdata_to_platdata() - decode standard SPI platform data 575 * 576 * This decodes the speed and mode for a slave from a device tree node 577 * 578 * @blob: Device tree blob 579 * @node: Node offset to read from 580 * @plat: Place to put the decoded information 581 */ 582 int spi_slave_ofdata_to_platdata(const void *blob, int node, 583 struct dm_spi_slave_platdata *plat); 584 585 /** 586 * spi_cs_info() - Check information on a chip select 587 * 588 * This checks a particular chip select on a bus to see if it has a device 589 * attached, or is even valid. 590 * 591 * @bus: The SPI bus 592 * @cs: The chip select (0..n-1) 593 * @info: Returns information about the chip select, if valid 594 * @return 0 if OK (and @info is set up), -ENODEV if the chip select 595 * is invalid, other -ve value on error 596 */ 597 int spi_cs_info(struct udevice *bus, uint cs, struct spi_cs_info *info); 598 599 struct sandbox_state; 600 601 /** 602 * sandbox_spi_get_emul() - get an emulator for a SPI slave 603 * 604 * This provides a way to attach an emulated SPI device to a particular SPI 605 * slave, so that xfer() operations on the slave will be handled by the 606 * emulator. If a emulator already exists on that chip select it is returned. 607 * Otherwise one is created. 608 * 609 * @state: Sandbox state 610 * @bus: SPI bus requesting the emulator 611 * @slave: SPI slave device requesting the emulator 612 * @emuip: Returns pointer to emulator 613 * @return 0 if OK, -ve on error 614 */ 615 int sandbox_spi_get_emul(struct sandbox_state *state, 616 struct udevice *bus, struct udevice *slave, 617 struct udevice **emulp); 618 619 /* Access the operations for a SPI device */ 620 #define spi_get_ops(dev) ((struct dm_spi_ops *)(dev)->driver->ops) 621 #define spi_emul_get_ops(dev) ((struct dm_spi_emul_ops *)(dev)->driver->ops) 622 #endif /* CONFIG_DM_SPI */ 623 624 #endif /* _SPI_H_ */ 625