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