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