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