1 /* SPDX-License-Identifier: GPL-2.0+ */
2 /*
3 * Common SPI Interface: Controller-specific definitions
4 *
5 * (C) Copyright 2001
6 * Gerald Van Baren, Custom IDEAS, vanbaren@cideas.com.
7 */
8
9 #ifndef _SPI_H_
10 #define _SPI_H_
11
12 #include <common.h>
13
14 /* SPI mode flags */
15 #define SPI_CPHA BIT(0) /* clock phase */
16 #define SPI_CPOL BIT(1) /* clock polarity */
17 #define SPI_MODE_0 (0|0) /* (original MicroWire) */
18 #define SPI_MODE_1 (0|SPI_CPHA)
19 #define SPI_MODE_2 (SPI_CPOL|0)
20 #define SPI_MODE_3 (SPI_CPOL|SPI_CPHA)
21 #define SPI_CS_HIGH BIT(2) /* CS active high */
22 #define SPI_LSB_FIRST BIT(3) /* per-word bits-on-wire */
23 #define SPI_3WIRE BIT(4) /* SI/SO signals shared */
24 #define SPI_LOOP BIT(5) /* loopback mode */
25 #define SPI_SLAVE BIT(6) /* slave mode */
26 #define SPI_PREAMBLE BIT(7) /* Skip preamble bytes */
27 #define SPI_TX_BYTE BIT(8) /* transmit with 1 wire byte */
28 #define SPI_TX_DUAL BIT(9) /* transmit with 2 wires */
29 #define SPI_TX_QUAD BIT(10) /* transmit with 4 wires */
30 #define SPI_RX_SLOW BIT(11) /* receive with 1 wire slow */
31 #define SPI_RX_DUAL BIT(12) /* receive with 2 wires */
32 #define SPI_RX_QUAD BIT(13) /* receive with 4 wires */
33
34 /* Header byte that marks the start of the message */
35 #define SPI_PREAMBLE_END_BYTE 0xec
36
37 #define SPI_DEFAULT_WORDLEN 8
38
39 #ifdef CONFIG_DM_SPI
40 /* TODO(sjg@chromium.org): Remove this and use max_hz from struct spi_slave */
41 struct dm_spi_bus {
42 uint max_hz;
43 };
44
45 /**
46 * struct dm_spi_platdata - platform data for all SPI slaves
47 *
48 * This describes a SPI slave, a child device of the SPI bus. To obtain this
49 * struct from a spi_slave, use dev_get_parent_platdata(dev) or
50 * dev_get_parent_platdata(slave->dev).
51 *
52 * This data is immuatable. Each time the device is probed, @max_hz and @mode
53 * will be copied to struct spi_slave.
54 *
55 * @cs: Chip select number (0..n-1)
56 * @max_hz: Maximum bus speed that this slave can tolerate
57 * @mode: SPI mode to use for this device (see SPI mode flags)
58 */
59 struct dm_spi_slave_platdata {
60 unsigned int cs;
61 uint max_hz;
62 uint mode;
63 };
64
65 #endif /* CONFIG_DM_SPI */
66
67 /**
68 * struct spi_slave - Representation of a SPI slave
69 *
70 * For driver model this is the per-child data used by the SPI bus. It can
71 * be accessed using dev_get_parent_priv() on the slave device. The SPI uclass
72 * sets uip per_child_auto_alloc_size to sizeof(struct spi_slave), and the
73 * driver should not override it. Two platform data fields (max_hz and mode)
74 * are copied into this structure to provide an initial value. This allows
75 * them to be changed, since we should never change platform data in drivers.
76 *
77 * If not using driver model, drivers are expected to extend this with
78 * controller-specific data.
79 *
80 * @dev: SPI slave device
81 * @max_hz: Maximum speed for this slave
82 * @speed: Current bus speed. This is 0 until the bus is first
83 * claimed.
84 * @bus: ID of the bus that the slave is attached to. For
85 * driver model this is the sequence number of the SPI
86 * bus (bus->seq) so does not need to be stored
87 * @cs: ID of the chip select connected to the slave.
88 * @mode: SPI mode to use for this slave (see SPI mode flags)
89 * @wordlen: Size of SPI word in number of bits
90 * @max_read_size: If non-zero, the maximum number of bytes which can
91 * be read at once.
92 * @max_write_size: If non-zero, the maximum number of bytes which can
93 * be written at once.
94 * @memory_map: Address of read-only SPI flash access.
95 * @flags: Indication of SPI flags.
96 */
97 struct spi_slave {
98 #ifdef CONFIG_DM_SPI
99 struct udevice *dev; /* struct spi_slave is dev->parentdata */
100 uint max_hz;
101 uint speed;
102 #else
103 unsigned int bus;
104 unsigned int cs;
105 #endif
106 uint mode;
107 unsigned int wordlen;
108 unsigned int max_read_size;
109 unsigned int max_write_size;
110 void *memory_map;
111
112 u8 flags;
113 #define SPI_XFER_BEGIN BIT(0) /* Assert CS before transfer */
114 #define SPI_XFER_END BIT(1) /* Deassert CS after transfer */
115 #define SPI_XFER_ONCE (SPI_XFER_BEGIN | SPI_XFER_END)
116 #define SPI_XFER_MMAP BIT(2) /* Memory Mapped start */
117 #define SPI_XFER_MMAP_END BIT(3) /* Memory Mapped End */
118 };
119
120 /**
121 * spi_do_alloc_slave - Allocate a new SPI slave (internal)
122 *
123 * Allocate and zero all fields in the spi slave, and set the bus/chip
124 * select. Use the helper macro spi_alloc_slave() to call this.
125 *
126 * @offset: Offset of struct spi_slave within slave structure.
127 * @size: Size of slave structure.
128 * @bus: Bus ID of the slave chip.
129 * @cs: Chip select ID of the slave chip on the specified bus.
130 */
131 void *spi_do_alloc_slave(int offset, int size, unsigned int bus,
132 unsigned int cs);
133
134 /**
135 * spi_alloc_slave - Allocate a new SPI slave
136 *
137 * Allocate and zero all fields in the spi slave, and set the bus/chip
138 * select.
139 *
140 * @_struct: Name of structure to allocate (e.g. struct tegra_spi).
141 * This structure must contain a member 'struct spi_slave *slave'.
142 * @bus: Bus ID of the slave chip.
143 * @cs: Chip select ID of the slave chip on the specified bus.
144 */
145 #define spi_alloc_slave(_struct, bus, cs) \
146 spi_do_alloc_slave(offsetof(_struct, slave), \
147 sizeof(_struct), bus, cs)
148
149 /**
150 * spi_alloc_slave_base - Allocate a new SPI slave with no private data
151 *
152 * Allocate and zero all fields in the spi slave, and set the bus/chip
153 * select.
154 *
155 * @bus: Bus ID of the slave chip.
156 * @cs: Chip select ID of the slave chip on the specified bus.
157 */
158 #define spi_alloc_slave_base(bus, cs) \
159 spi_do_alloc_slave(0, sizeof(struct spi_slave), bus, cs)
160
161 /**
162 * Set up communications parameters for a SPI slave.
163 *
164 * This must be called once for each slave. Note that this function
165 * usually doesn't touch any actual hardware, it only initializes the
166 * contents of spi_slave so that the hardware can be easily
167 * initialized later.
168 *
169 * @bus: Bus ID of the slave chip.
170 * @cs: Chip select ID of the slave chip on the specified bus.
171 * @max_hz: Maximum SCK rate in Hz.
172 * @mode: Clock polarity, clock phase and other parameters.
173 *
174 * Returns: A spi_slave reference that can be used in subsequent SPI
175 * calls, or NULL if one or more of the parameters are not supported.
176 */
177 struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
178 unsigned int max_hz, unsigned int mode);
179
180 /**
181 * Free any memory associated with a SPI slave.
182 *
183 * @slave: The SPI slave
184 */
185 void spi_free_slave(struct spi_slave *slave);
186
187 /**
188 * Claim the bus and prepare it for communication with a given slave.
189 *
190 * This must be called before doing any transfers with a SPI slave. It
191 * will enable and initialize any SPI hardware as necessary, and make
192 * sure that the SCK line is in the correct idle state. It is not
193 * allowed to claim the same bus for several slaves without releasing
194 * the bus in between.
195 *
196 * @slave: The SPI slave
197 *
198 * Returns: 0 if the bus was claimed successfully, or a negative value
199 * if it wasn't.
200 */
201 int spi_claim_bus(struct spi_slave *slave);
202
203 /**
204 * Release the SPI bus
205 *
206 * This must be called once for every call to spi_claim_bus() after
207 * all transfers have finished. It may disable any SPI hardware as
208 * appropriate.
209 *
210 * @slave: The SPI slave
211 */
212 void spi_release_bus(struct spi_slave *slave);
213
214 /**
215 * Set the word length for SPI transactions
216 *
217 * Set the word length (number of bits per word) for SPI transactions.
218 *
219 * @slave: The SPI slave
220 * @wordlen: The number of bits in a word
221 *
222 * Returns: 0 on success, -1 on failure.
223 */
224 int spi_set_wordlen(struct spi_slave *slave, unsigned int wordlen);
225
226 /**
227 * SPI transfer
228 *
229 * This writes "bitlen" bits out the SPI MOSI port and simultaneously clocks
230 * "bitlen" bits in the SPI MISO port. That's just the way SPI works.
231 *
232 * The source of the outgoing bits is the "dout" parameter and the
233 * destination of the input bits is the "din" parameter. Note that "dout"
234 * and "din" can point to the same memory location, in which case the
235 * input data overwrites the output data (since both are buffered by
236 * temporary variables, this is OK).
237 *
238 * spi_xfer() interface:
239 * @slave: The SPI slave which will be sending/receiving the data.
240 * @bitlen: How many bits to write and read.
241 * @dout: Pointer to a string of bits to send out. The bits are
242 * held in a byte array and are sent MSB first.
243 * @din: Pointer to a string of bits that will be filled in.
244 * @flags: A bitwise combination of SPI_XFER_* flags.
245 *
246 * Returns: 0 on success, not 0 on failure
247 */
248 int spi_xfer(struct spi_slave *slave, unsigned int bitlen, const void *dout,
249 void *din, unsigned long flags);
250
251 /* Copy memory mapped data */
252 void spi_flash_copy_mmap(void *data, void *offset, size_t len);
253
254 /**
255 * Determine if a SPI chipselect is valid.
256 * This function is provided by the board if the low-level SPI driver
257 * needs it to determine if a given chipselect is actually valid.
258 *
259 * Returns: 1 if bus:cs identifies a valid chip on this board, 0
260 * otherwise.
261 */
262 int spi_cs_is_valid(unsigned int bus, unsigned int cs);
263
264 #ifndef CONFIG_DM_SPI
265 /**
266 * Activate a SPI chipselect.
267 * This function is provided by the board code when using a driver
268 * that can't control its chipselects automatically (e.g.
269 * common/soft_spi.c). When called, it should activate the chip select
270 * to the device identified by "slave".
271 */
272 void spi_cs_activate(struct spi_slave *slave);
273
274 /**
275 * Deactivate a SPI chipselect.
276 * This function is provided by the board code when using a driver
277 * that can't control its chipselects automatically (e.g.
278 * common/soft_spi.c). When called, it should deactivate the chip
279 * select to the device identified by "slave".
280 */
281 void spi_cs_deactivate(struct spi_slave *slave);
282
283 /**
284 * Set transfer speed.
285 * This sets a new speed to be applied for next spi_xfer().
286 * @slave: The SPI slave
287 * @hz: The transfer speed
288 */
289 void spi_set_speed(struct spi_slave *slave, uint hz);
290 #endif
291
292 /**
293 * Write 8 bits, then read 8 bits.
294 * @slave: The SPI slave we're communicating with
295 * @byte: Byte to be written
296 *
297 * Returns: The value that was read, or a negative value on error.
298 *
299 * TODO: This function probably shouldn't be inlined.
300 */
spi_w8r8(struct spi_slave * slave,unsigned char byte)301 static inline int spi_w8r8(struct spi_slave *slave, unsigned char byte)
302 {
303 unsigned char dout[2];
304 unsigned char din[2];
305 int ret;
306
307 dout[0] = byte;
308 dout[1] = 0;
309
310 ret = spi_xfer(slave, 16, dout, din, SPI_XFER_BEGIN | SPI_XFER_END);
311 return ret < 0 ? ret : din[1];
312 }
313
314 #ifdef CONFIG_DM_SPI
315
316 /**
317 * struct spi_cs_info - Information about a bus chip select
318 *
319 * @dev: Connected device, or NULL if none
320 */
321 struct spi_cs_info {
322 struct udevice *dev;
323 };
324
325 /**
326 * struct struct dm_spi_ops - Driver model SPI operations
327 *
328 * The uclass interface is implemented by all SPI devices which use
329 * driver model.
330 */
331 struct dm_spi_ops {
332 /**
333 * Claim the bus and prepare it for communication.
334 *
335 * The device provided is the slave device. It's parent controller
336 * will be used to provide the communication.
337 *
338 * This must be called before doing any transfers with a SPI slave. It
339 * will enable and initialize any SPI hardware as necessary, and make
340 * sure that the SCK line is in the correct idle state. It is not
341 * allowed to claim the same bus for several slaves without releasing
342 * the bus in between.
343 *
344 * @dev: The SPI slave
345 *
346 * Returns: 0 if the bus was claimed successfully, or a negative value
347 * if it wasn't.
348 */
349 int (*claim_bus)(struct udevice *dev);
350
351 /**
352 * Release the SPI bus
353 *
354 * This must be called once for every call to spi_claim_bus() after
355 * all transfers have finished. It may disable any SPI hardware as
356 * appropriate.
357 *
358 * @dev: The SPI slave
359 */
360 int (*release_bus)(struct udevice *dev);
361
362 /**
363 * Set the word length for SPI transactions
364 *
365 * Set the word length (number of bits per word) for SPI transactions.
366 *
367 * @bus: The SPI slave
368 * @wordlen: The number of bits in a word
369 *
370 * Returns: 0 on success, -ve on failure.
371 */
372 int (*set_wordlen)(struct udevice *dev, unsigned int wordlen);
373
374 /**
375 * SPI transfer
376 *
377 * This writes "bitlen" bits out the SPI MOSI port and simultaneously
378 * clocks "bitlen" bits in the SPI MISO port. That's just the way SPI
379 * works.
380 *
381 * The source of the outgoing bits is the "dout" parameter and the
382 * destination of the input bits is the "din" parameter. Note that
383 * "dout" and "din" can point to the same memory location, in which
384 * case the input data overwrites the output data (since both are
385 * buffered by temporary variables, this is OK).
386 *
387 * spi_xfer() interface:
388 * @dev: The slave device to communicate with
389 * @bitlen: How many bits to write and read.
390 * @dout: Pointer to a string of bits to send out. The bits are
391 * held in a byte array and are sent MSB first.
392 * @din: Pointer to a string of bits that will be filled in.
393 * @flags: A bitwise combination of SPI_XFER_* flags.
394 *
395 * Returns: 0 on success, not -1 on failure
396 */
397 int (*xfer)(struct udevice *dev, unsigned int bitlen, const void *dout,
398 void *din, unsigned long flags);
399
400 /**
401 * Optimized handlers for SPI memory-like operations.
402 *
403 * Optimized/dedicated operations for interactions with SPI memory. This
404 * field is optional and should only be implemented if the controller
405 * has native support for memory like operations.
406 */
407 const struct spi_controller_mem_ops *mem_ops;
408
409 /**
410 * Set transfer speed.
411 * This sets a new speed to be applied for next spi_xfer().
412 * @bus: The SPI bus
413 * @hz: The transfer speed
414 * @return 0 if OK, -ve on error
415 */
416 int (*set_speed)(struct udevice *bus, uint hz);
417
418 /**
419 * Set the SPI mode/flags
420 *
421 * It is unclear if we want to set speed and mode together instead
422 * of separately.
423 *
424 * @bus: The SPI bus
425 * @mode: Requested SPI mode (SPI_... flags)
426 * @return 0 if OK, -ve on error
427 */
428 int (*set_mode)(struct udevice *bus, uint mode);
429
430 /**
431 * Get information on a chip select
432 *
433 * This is only called when the SPI uclass does not know about a
434 * chip select, i.e. it has no attached device. It gives the driver
435 * a chance to allow activity on that chip select even so.
436 *
437 * @bus: The SPI bus
438 * @cs: The chip select (0..n-1)
439 * @info: Returns information about the chip select, if valid.
440 * On entry info->dev is NULL
441 * @return 0 if OK (and @info is set up), -ENODEV if the chip select
442 * is invalid, other -ve value on error
443 */
444 int (*cs_info)(struct udevice *bus, uint cs, struct spi_cs_info *info);
445
446 int (*mem_ctrl_wlock)(struct udevice *dev, u32 offset, size_t len);
447 int (*mem_ctrl_wunlock)(struct udevice *dev, u32 offset, size_t len);
448 };
449
450 struct dm_spi_emul_ops {
451 /**
452 * SPI transfer
453 *
454 * This writes "bitlen" bits out the SPI MOSI port and simultaneously
455 * clocks "bitlen" bits in the SPI MISO port. That's just the way SPI
456 * works. Here the device is a slave.
457 *
458 * The source of the outgoing bits is the "dout" parameter and the
459 * destination of the input bits is the "din" parameter. Note that
460 * "dout" and "din" can point to the same memory location, in which
461 * case the input data overwrites the output data (since both are
462 * buffered by temporary variables, this is OK).
463 *
464 * spi_xfer() interface:
465 * @slave: The SPI slave which will be sending/receiving the data.
466 * @bitlen: How many bits to write and read.
467 * @dout: Pointer to a string of bits sent to the device. The
468 * bits are held in a byte array and are sent MSB first.
469 * @din: Pointer to a string of bits that will be sent back to
470 * the master.
471 * @flags: A bitwise combination of SPI_XFER_* flags.
472 *
473 * Returns: 0 on success, not -1 on failure
474 */
475 int (*xfer)(struct udevice *slave, unsigned int bitlen,
476 const void *dout, void *din, unsigned long flags);
477 };
478
479 /**
480 * spi_find_bus_and_cs() - Find bus and slave devices by number
481 *
482 * Given a bus number and chip select, this finds the corresponding bus
483 * device and slave device. Neither device is activated by this function,
484 * although they may have been activated previously.
485 *
486 * @busnum: SPI bus number
487 * @cs: Chip select to look for
488 * @busp: Returns bus device
489 * @devp: Return slave device
490 * @return 0 if found, -ENODEV on error
491 */
492 int spi_find_bus_and_cs(int busnum, int cs, struct udevice **busp,
493 struct udevice **devp);
494
495 /**
496 * spi_get_bus_and_cs() - Find and activate bus and slave devices by number
497 *
498 * Given a bus number and chip select, this finds the corresponding bus
499 * device and slave device.
500 *
501 * If no such slave exists, and drv_name is not NULL, then a new slave device
502 * is automatically bound on this chip select.
503 *
504 * Ths new slave device is probed ready for use with the given speed and mode.
505 *
506 * @busnum: SPI bus number
507 * @cs: Chip select to look for
508 * @speed: SPI speed to use for this slave
509 * @mode: SPI mode to use for this slave
510 * @drv_name: Name of driver to attach to this chip select
511 * @dev_name: Name of the new device thus created
512 * @busp: Returns bus device
513 * @devp: Return slave device
514 * @return 0 if found, -ve on error
515 */
516 int spi_get_bus_and_cs(int busnum, int cs, int speed, int mode,
517 const char *drv_name, const char *dev_name,
518 struct udevice **busp, struct spi_slave **devp);
519
520 /**
521 * spi_chip_select() - Get the chip select for a slave
522 *
523 * @return the chip select this slave is attached to
524 */
525 int spi_chip_select(struct udevice *slave);
526
527 /**
528 * spi_find_chip_select() - Find the slave attached to chip select
529 *
530 * @bus: SPI bus to search
531 * @cs: Chip select to look for
532 * @devp: Returns the slave device if found
533 * @return 0 if found, -ENODEV on error
534 */
535 int spi_find_chip_select(struct udevice *bus, int cs, struct udevice **devp);
536
537 /**
538 * spi_slave_ofdata_to_platdata() - decode standard SPI platform data
539 *
540 * This decodes the speed and mode for a slave from a device tree node
541 *
542 * @blob: Device tree blob
543 * @node: Node offset to read from
544 * @plat: Place to put the decoded information
545 */
546 int spi_slave_ofdata_to_platdata(struct udevice *dev,
547 struct dm_spi_slave_platdata *plat);
548
549 /**
550 * spi_cs_info() - Check information on a chip select
551 *
552 * This checks a particular chip select on a bus to see if it has a device
553 * attached, or is even valid.
554 *
555 * @bus: The SPI bus
556 * @cs: The chip select (0..n-1)
557 * @info: Returns information about the chip select, if valid
558 * @return 0 if OK (and @info is set up), -ENODEV if the chip select
559 * is invalid, other -ve value on error
560 */
561 int spi_cs_info(struct udevice *bus, uint cs, struct spi_cs_info *info);
562
563 struct sandbox_state;
564
565 /**
566 * sandbox_spi_get_emul() - get an emulator for a SPI slave
567 *
568 * This provides a way to attach an emulated SPI device to a particular SPI
569 * slave, so that xfer() operations on the slave will be handled by the
570 * emulator. If a emulator already exists on that chip select it is returned.
571 * Otherwise one is created.
572 *
573 * @state: Sandbox state
574 * @bus: SPI bus requesting the emulator
575 * @slave: SPI slave device requesting the emulator
576 * @emuip: Returns pointer to emulator
577 * @return 0 if OK, -ve on error
578 */
579 int sandbox_spi_get_emul(struct sandbox_state *state,
580 struct udevice *bus, struct udevice *slave,
581 struct udevice **emulp);
582
583 /**
584 * Claim the bus and prepare it for communication with a given slave.
585 *
586 * This must be called before doing any transfers with a SPI slave. It
587 * will enable and initialize any SPI hardware as necessary, and make
588 * sure that the SCK line is in the correct idle state. It is not
589 * allowed to claim the same bus for several slaves without releasing
590 * the bus in between.
591 *
592 * @dev: The SPI slave device
593 *
594 * Returns: 0 if the bus was claimed successfully, or a negative value
595 * if it wasn't.
596 */
597 int dm_spi_claim_bus(struct udevice *dev);
598
599 /**
600 * Release the SPI bus
601 *
602 * This must be called once for every call to dm_spi_claim_bus() after
603 * all transfers have finished. It may disable any SPI hardware as
604 * appropriate.
605 *
606 * @slave: The SPI slave device
607 */
608 void dm_spi_release_bus(struct udevice *dev);
609
610 /**
611 * SPI transfer
612 *
613 * This writes "bitlen" bits out the SPI MOSI port and simultaneously clocks
614 * "bitlen" bits in the SPI MISO port. That's just the way SPI works.
615 *
616 * The source of the outgoing bits is the "dout" parameter and the
617 * destination of the input bits is the "din" parameter. Note that "dout"
618 * and "din" can point to the same memory location, in which case the
619 * input data overwrites the output data (since both are buffered by
620 * temporary variables, this is OK).
621 *
622 * dm_spi_xfer() interface:
623 * @dev: The SPI slave device which will be sending/receiving the data.
624 * @bitlen: How many bits to write and read.
625 * @dout: Pointer to a string of bits to send out. The bits are
626 * held in a byte array and are sent MSB first.
627 * @din: Pointer to a string of bits that will be filled in.
628 * @flags: A bitwise combination of SPI_XFER_* flags.
629 *
630 * Returns: 0 on success, not 0 on failure
631 */
632 int dm_spi_xfer(struct udevice *dev, unsigned int bitlen,
633 const void *dout, void *din, unsigned long flags);
634
635 /* Access the operations for a SPI device */
636 #define spi_get_ops(dev) ((struct dm_spi_ops *)(dev)->driver->ops)
637 #define spi_emul_get_ops(dev) ((struct dm_spi_emul_ops *)(dev)->driver->ops)
638 #endif /* CONFIG_DM_SPI */
639
640 #endif /* _SPI_H_ */
641