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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 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#define SPI_TX_BYTE (1<<8) /* transmit with 1 wire byte */
27#define SPI_TX_DUAL (1<<9) /* transmit with 2 wires */
28#define SPI_TX_QUAD (1<<10) /* transmit with 4 wires */
29#define SPI_RX_SLOW (1<<11) /* receive with 1 wire slow */
30#define SPI_RX_DUAL (1<<12) /* receive with 2 wires */
31#define SPI_RX_QUAD (1<<13) /* receive with 4 wires */
32
33
34/* SPI transfer flags */
35#define SPI_XFER_BEGIN 0x01 /* Assert CS before transfer */
36#define SPI_XFER_END 0x02 /* Deassert CS after transfer */
37#define SPI_XFER_MMAP 0x08 /* Memory Mapped start */
38#define SPI_XFER_MMAP_END 0x10 /* Memory Mapped End */
39#define SPI_XFER_ONCE (SPI_XFER_BEGIN | SPI_XFER_END)
40#define SPI_XFER_U_PAGE (1 << 5)
41
42/* SPI TX operation modes */
43#define SPI_OPM_TX_QPP (1 << 0)
44#define SPI_OPM_TX_BP (1 << 1)
45
46/* SPI RX operation modes */
47#define SPI_OPM_RX_AS (1 << 0)
48#define SPI_OPM_RX_AF (1 << 1)
49#define SPI_OPM_RX_DOUT (1 << 2)
50#define SPI_OPM_RX_DIO (1 << 3)
51#define SPI_OPM_RX_QOF (1 << 4)
52#define SPI_OPM_RX_QIOF (1 << 5)
53#define SPI_OPM_RX_EXTN (SPI_OPM_RX_AS | SPI_OPM_RX_DOUT | \
54 SPI_OPM_RX_DIO | SPI_OPM_RX_QOF | \
55 SPI_OPM_RX_QIOF)
56
57/* SPI bus connection options - see enum spi_dual_flash */
58#define SPI_CONN_DUAL_SHARED (1 << 0)
59#define SPI_CONN_DUAL_SEPARATED (1 << 1)
60
61/* Header byte that marks the start of the message */
62#define SPI_PREAMBLE_END_BYTE 0xec
63
64#define SPI_DEFAULT_WORDLEN 8
65
66#ifdef CONFIG_DM_SPI
67struct dm_spi_bus {
68 uint max_hz;
69};
70
71#endif /* CONFIG_DM_SPI */
72
73/**
74 * struct spi_slave - Representation of a SPI slave
75 *
76 * For driver model this is the per-child data used by the SPI bus. It can
77 * be accessed using dev_get_parentdata() on the slave device. Each SPI
78 * driver should define this child data in its U_BOOT_DRIVER() definition:
79 *
80 * .per_child_auto_alloc_size = sizeof(struct spi_slave),
81 *
82 * If not using driver model, drivers are expected to extend this with
83 * controller-specific data.
84 *
85 * @dev: SPI slave device
86 * @max_hz: Maximum speed for this slave
87 * @mode: SPI mode to use for this slave (see SPI mode flags)
88 * @bus: ID of the bus that the slave is attached to. For
89 * driver model this is the sequence number of the SPI
90 * bus (bus->seq) so does not need to be stored
91 * @cs: ID of the chip select connected to the slave.
92 * @op_mode_rx: SPI RX operation mode.
93 * @op_mode_tx: SPI TX operation mode.
94 * @wordlen: Size of SPI word in number of bits
95 * @max_write_size: If non-zero, the maximum number of bytes which can
96 * be written at once, excluding command bytes.
97 * @memory_map: Address of read-only SPI flash access.
98 * @option: Varies SPI bus options - separate, shared bus.
99 * @flags: Indication of SPI flags.
100 */
101struct spi_slave {
102#ifdef CONFIG_DM_SPI
103 struct udevice *dev; /* struct spi_slave is dev->parentdata */
104 uint max_hz;
105 uint mode;
106#else
107 unsigned int bus;
108#endif
109 unsigned int cs;
110 u8 op_mode_rx;
111 u8 op_mode_tx;
112 unsigned int wordlen;
113 unsigned int max_write_size;
114 void *memory_map;
115 u8 option;
116 u8 flags;
117};
118
119/**
120 * Initialization, must be called once on start up.
121 *
122 * TODO: I don't think we really need this.
123 */
124void spi_init(void);
125
126/**
127 * spi_do_alloc_slave - Allocate a new SPI slave (internal)
128 *
129 * Allocate and zero all fields in the spi slave, and set the bus/chip
130 * select. Use the helper macro spi_alloc_slave() to call this.
131 *
132 * @offset: Offset of struct spi_slave within slave structure.
133 * @size: Size of slave structure.
134 * @bus: Bus ID of the slave chip.
135 * @cs: Chip select ID of the slave chip on the specified bus.
136 */
137void *spi_do_alloc_slave(int offset, int size, unsigned int bus,
138 unsigned int cs);
139
140/**
141 * spi_alloc_slave - Allocate a new SPI slave
142 *
143 * Allocate and zero all fields in the spi slave, and set the bus/chip
144 * select.
145 *
146 * @_struct: Name of structure to allocate (e.g. struct tegra_spi).
147 * This structure must contain a member 'struct spi_slave *slave'.
148 * @bus: Bus ID of the slave chip.
149 * @cs: Chip select ID of the slave chip on the specified bus.
150 */
151#define spi_alloc_slave(_struct, bus, cs) \
152 spi_do_alloc_slave(offsetof(_struct, slave), \
153 sizeof(_struct), bus, cs)
154
155/**
156 * spi_alloc_slave_base - Allocate a new SPI slave with no private data
157 *
158 * Allocate and zero all fields in the spi slave, and set the bus/chip
159 * select.
160 *
161 * @bus: Bus ID of the slave chip.
162 * @cs: Chip select ID of the slave chip on the specified bus.
163 */
164#define spi_alloc_slave_base(bus, cs) \
165 spi_do_alloc_slave(0, sizeof(struct spi_slave), bus, cs)
166
167/**
168 * Set up communications parameters for a SPI slave.
169 *
170 * This must be called once for each slave. Note that this function
171 * usually doesn't touch any actual hardware, it only initializes the
172 * contents of spi_slave so that the hardware can be easily
173 * initialized later.
174 *
175 * @bus: Bus ID of the slave chip.
176 * @cs: Chip select ID of the slave chip on the specified bus.
177 * @max_hz: Maximum SCK rate in Hz.
178 * @mode: Clock polarity, clock phase and other parameters.
179 *
180 * Returns: A spi_slave reference that can be used in subsequent SPI
181 * calls, or NULL if one or more of the parameters are not supported.
182 */
183struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
184 unsigned int max_hz, unsigned int mode);
185
186/**
187 * Free any memory associated with a SPI slave.
188 *
189 * @slave: The SPI slave
190 */
191void spi_free_slave(struct spi_slave *slave);
192
193/**
194 * Claim the bus and prepare it for communication with a given slave.
195 *
196 * This must be called before doing any transfers with a SPI slave. It
197 * will enable and initialize any SPI hardware as necessary, and make
198 * sure that the SCK line is in the correct idle state. It is not
199 * allowed to claim the same bus for several slaves without releasing
200 * the bus in between.
201 *
202 * @slave: The SPI slave
203 *
204 * Returns: 0 if the bus was claimed successfully, or a negative value
205 * if it wasn't.
206 */
207int spi_claim_bus(struct spi_slave *slave);
208
209/**
210 * Release the SPI bus
211 *
212 * This must be called once for every call to spi_claim_bus() after
213 * all transfers have finished. It may disable any SPI hardware as
214 * appropriate.
215 *
216 * @slave: The SPI slave
217 */
218void spi_release_bus(struct spi_slave *slave);
219
220/**
221 * Set the word length for SPI transactions
222 *
223 * Set the word length (number of bits per word) for SPI transactions.
224 *
225 * @slave: The SPI slave
226 * @wordlen: The number of bits in a word
227 *
228 * Returns: 0 on success, -1 on failure.
229 */
230int spi_set_wordlen(struct spi_slave *slave, unsigned int wordlen);
231
232/**
233 * SPI transfer
234 *
235 * This writes "bitlen" bits out the SPI MOSI port and simultaneously clocks
236 * "bitlen" bits in the SPI MISO port. That's just the way SPI works.
237 *
238 * The source of the outgoing bits is the "dout" parameter and the
239 * destination of the input bits is the "din" parameter. Note that "dout"
240 * and "din" can point to the same memory location, in which case the
241 * input data overwrites the output data (since both are buffered by
242 * temporary variables, this is OK).
243 *
244 * spi_xfer() interface:
245 * @slave: The SPI slave which will be sending/receiving the data.
246 * @bitlen: How many bits to write and read.
247 * @dout: Pointer to a string of bits to send out. The bits are
248 * held in a byte array and are sent MSB first.
249 * @din: Pointer to a string of bits that will be filled in.
250 * @flags: A bitwise combination of SPI_XFER_* flags.
251 *
252 * Returns: 0 on success, not 0 on failure
253 */
254int spi_xfer(struct spi_slave *slave, unsigned int bitlen, const void *dout,
255 void *din, unsigned long flags);
256
257/**
258 * Determine if a SPI chipselect is valid.
259 * This function is provided by the board if the low-level SPI driver
260 * needs it to determine if a given chipselect is actually valid.
261 *
262 * Returns: 1 if bus:cs identifies a valid chip on this board, 0
263 * otherwise.
264 */
265int spi_cs_is_valid(unsigned int bus, unsigned int cs);
266
267/**
268 * We have to define spi_cs_activate/deactivate for those tranditional
269 * driver though in DM.
270 */
271/**
272 * Activate a SPI chipselect.
273 * This function is provided by the board code when using a driver
274 * that can't control its chipselects automatically (e.g.
275 * common/soft_spi.c). When called, it should activate the chip select
276 * to the device identified by "slave".
277 */
278void spi_cs_activate(struct spi_slave *slave);
279
280/**
281 * Deactivate a SPI chipselect.
282 * This function is provided by the board code when using a driver
283 * that can't control its chipselects automatically (e.g.
284 * common/soft_spi.c). When called, it should deactivate the chip
285 * select to the device identified by "slave".
286 */
287void spi_cs_deactivate(struct spi_slave *slave);
288
289#ifndef CONFIG_DM_SPI
290/**
291 * Set transfer speed.
292 * This sets a new speed to be applied for next spi_xfer().
293 * @slave: The SPI slave
294 * @hz: The transfer speed
295 */
296void spi_set_speed(struct spi_slave *slave, uint hz);
297#endif
298
299/**
300 * Write 8 bits, then read 8 bits.
301 * @slave: The SPI slave we're communicating with
302 * @byte: Byte to be written
303 *
304 * Returns: The value that was read, or a negative value on error.
305 *
306 * TODO: This function probably shouldn't be inlined.
307 */
308static inline int spi_w8r8(struct spi_slave *slave, unsigned char byte)
309{
310 unsigned char dout[2];
311 unsigned char din[2];
312 int ret;
313
314 dout[0] = byte;
315 dout[1] = 0;
316
317 ret = spi_xfer(slave, 16, dout, din, SPI_XFER_BEGIN | SPI_XFER_END);
318 return ret < 0 ? ret : din[1];
319}
320
321/**
322 * Set up a SPI slave for a particular device tree node
323 *
324 * This calls spi_setup_slave() with the correct bus number. Call
325 * spi_free_slave() to free it later.
326 *
327 * @param blob: Device tree blob
328 * @param slave_node: Slave node to use
329 * @param spi_node: SPI peripheral node to use
330 * @return pointer to new spi_slave structure
331 */
332struct spi_slave *spi_setup_slave_fdt(const void *blob, int slave_node,
333 int spi_node);
334
335/**
336 * spi_base_setup_slave_fdt() - helper function to set up a SPI slace
337 *
338 * This decodes SPI properties from the slave node to determine the
339 * chip select and SPI parameters.
340 *
341 * @blob: Device tree blob
342 * @busnum: Bus number to use
343 * @node: Device tree node for the SPI bus
344 */
345struct spi_slave *spi_base_setup_slave_fdt(const void *blob, int busnum,
346 int node);
347
348#ifdef CONFIG_DM_SPI
349
350/**
351 * struct spi_cs_info - Information about a bus chip select
352 *
353 * @dev: Connected device, or NULL if none
354 */
355struct spi_cs_info {
356 struct udevice *dev;
357};
358
359/**
360 * struct struct dm_spi_ops - Driver model SPI operations
361 *
362 * The uclass interface is implemented by all SPI devices which use
363 * driver model.
364 */
365struct dm_spi_ops {
366 /**
367 * Claim the bus and prepare it for communication.
368 *
369 * The device provided is the slave device. It's parent controller
370 * will be used to provide the communication.
371 *
372 * This must be called before doing any transfers with a SPI slave. It
373 * will enable and initialize any SPI hardware as necessary, and make
374 * sure that the SCK line is in the correct idle state. It is not
375 * allowed to claim the same bus for several slaves without releasing
376 * the bus in between.
377 *
378 * @bus: The SPI slave
379 *
380 * Returns: 0 if the bus was claimed successfully, or a negative value
381 * if it wasn't.
382 */
383 int (*claim_bus)(struct udevice *bus);
384
385 /**
386 * Release the SPI bus
387 *
388 * This must be called once for every call to spi_claim_bus() after
389 * all transfers have finished. It may disable any SPI hardware as
390 * appropriate.
391 *
392 * @bus: The SPI slave
393 */
394 int (*release_bus)(struct udevice *bus);
395
396 /**
397 * Set the word length for SPI transactions
398 *
399 * Set the word length (number of bits per word) for SPI transactions.
400 *
401 * @bus: The SPI slave
402 * @wordlen: The number of bits in a word
403 *
404 * Returns: 0 on success, -ve on failure.
405 */
406 int (*set_wordlen)(struct udevice *bus, unsigned int wordlen);
407
408 /**
409 * SPI transfer
410 *
411 * This writes "bitlen" bits out the SPI MOSI port and simultaneously
412 * clocks "bitlen" bits in the SPI MISO port. That's just the way SPI
413 * works.
414 *
415 * The source of the outgoing bits is the "dout" parameter and the
416 * destination of the input bits is the "din" parameter. Note that
417 * "dout" and "din" can point to the same memory location, in which
418 * case the input data overwrites the output data (since both are
419 * buffered by temporary variables, this is OK).
420 *
421 * spi_xfer() interface:
422 * @dev: The slave device to communicate with
423 * @bitlen: How many bits to write and read.
424 * @dout: Pointer to a string of bits to send out. The bits are
425 * held in a byte array and are sent MSB first.
426 * @din: Pointer to a string of bits that will be filled in.
427 * @flags: A bitwise combination of SPI_XFER_* flags.
428 *
429 * Returns: 0 on success, not -1 on failure
430 */
431 int (*xfer)(struct udevice *dev, unsigned int bitlen, const void *dout,
432 void *din, unsigned long flags);
433
434 /**
435 * Set transfer speed.
436 * This sets a new speed to be applied for next spi_xfer().
437 * @bus: The SPI bus
438 * @hz: The transfer speed
439 * @return 0 if OK, -ve on error
440 */
441 int (*set_speed)(struct udevice *bus, uint hz);
442
443 /**
444 * Set the SPI mode/flags
445 *
446 * It is unclear if we want to set speed and mode together instead
447 * of separately.
448 *
449 * @bus: The SPI bus
450 * @mode: Requested SPI mode (SPI_... flags)
451 * @return 0 if OK, -ve on error
452 */
453 int (*set_mode)(struct udevice *bus, uint mode);
454
455 /**
456 * Get information on a chip select
457 *
458 * This is only called when the SPI uclass does not know about a
459 * chip select, i.e. it has no attached device. It gives the driver
460 * a chance to allow activity on that chip select even so.
461 *
462 * @bus: The SPI bus
463 * @cs: The chip select (0..n-1)
464 * @info: Returns information about the chip select, if valid.
465 * On entry info->dev is NULL
466 * @return 0 if OK (and @info is set up), -ENODEV if the chip select
467 * is invalid, other -ve value on error
468 */
469 int (*cs_info)(struct udevice *bus, uint cs, struct spi_cs_info *info);
470};
471
472struct dm_spi_emul_ops {
473 /**
474 * SPI transfer
475 *
476 * This writes "bitlen" bits out the SPI MOSI port and simultaneously
477 * clocks "bitlen" bits in the SPI MISO port. That's just the way SPI
478 * works. Here the device is a slave.
479 *
480 * The source of the outgoing bits is the "dout" parameter and the
481 * destination of the input bits is the "din" parameter. Note that
482 * "dout" and "din" can point to the same memory location, in which
483 * case the input data overwrites the output data (since both are
484 * buffered by temporary variables, this is OK).
485 *
486 * spi_xfer() interface:
487 * @slave: The SPI slave which will be sending/receiving the data.
488 * @bitlen: How many bits to write and read.
489 * @dout: Pointer to a string of bits sent to the device. The
490 * bits are held in a byte array and are sent MSB first.
491 * @din: Pointer to a string of bits that will be sent back to
492 * the master.
493 * @flags: A bitwise combination of SPI_XFER_* flags.
494 *
495 * Returns: 0 on success, not -1 on failure
496 */
497 int (*xfer)(struct udevice *slave, unsigned int bitlen,
498 const void *dout, void *din, unsigned long flags);
499};
500
501/**
502 * spi_find_bus_and_cs() - Find bus and slave devices by number
503 *
504 * Given a bus number and chip select, this finds the corresponding bus
505 * device and slave device. Neither device is activated by this function,
506 * although they may have been activated previously.
507 *
508 * @busnum: SPI bus number
509 * @cs: Chip select to look for
510 * @busp: Returns bus device
511 * @devp: Return slave device
512 * @return 0 if found, -ENODEV on error
513 */
514int spi_find_bus_and_cs(int busnum, int cs, struct udevice **busp,
515 struct udevice **devp);
516
517/**
518 * spi_get_bus_and_cs() - Find and activate bus and slave devices by number
519 *
520 * Given a bus number and chip select, this finds the corresponding bus
521 * device and slave device.
522 *
523 * If no such slave exists, and drv_name is not NULL, then a new slave device
524 * is automatically bound on this chip select.
525 *
526 * Ths new slave device is probed ready for use with the given speed and mode.
527 *
528 * @busnum: SPI bus number
529 * @cs: Chip select to look for
530 * @speed: SPI speed to use for this slave
531 * @mode: SPI mode to use for this slave
532 * @drv_name: Name of driver to attach to this chip select
533 * @dev_name: Name of the new device thus created
534 * @busp: Returns bus device
535 * @devp: Return slave device
536 * @return 0 if found, -ve on error
537 */
538int spi_get_bus_and_cs(int busnum, int cs, int speed, int mode,
539 const char *drv_name, const char *dev_name,
540 struct udevice **busp, struct spi_slave **devp);
541
542/**
543 * spi_chip_select() - Get the chip select for a slave
544 *
545 * @return the chip select this slave is attached to
546 */
547int spi_chip_select(struct udevice *slave);
548
549/**
550 * spi_find_chip_select() - Find the slave attached to chip select
551 *
552 * @bus: SPI bus to search
553 * @cs: Chip select to look for
554 * @devp: Returns the slave device if found
555 * @return 0 if found, -ENODEV on error
556 */
557int spi_find_chip_select(struct udevice *bus, int cs, struct udevice **devp);
558
559/**
560 * spi_ofdata_to_platdata() - decode standard SPI platform data
561 *
562 * This decodes the speed and mode from a device tree node and puts it into
563 * the spi_slave structure.
564 *
565 * @blob: Device tree blob
566 * @node: Node offset to read from
567 * @spi: Place to put the decoded information
568 */
569int spi_ofdata_to_platdata(const void *blob, int node, struct spi_slave *spi);
570
571/**
572 * spi_cs_info() - Check information on a chip select
573 *
574 * This checks a particular chip select on a bus to see if it has a device
575 * attached, or is even valid.
576 *
577 * @bus: The SPI bus
578 * @cs: The chip select (0..n-1)
579 * @info: Returns information about the chip select, if valid
580 * @return 0 if OK (and @info is set up), -ENODEV if the chip select
581 * is invalid, other -ve value on error
582 */
583int spi_cs_info(struct udevice *bus, uint cs, struct spi_cs_info *info);
584
585struct sandbox_state;
586
587/**
588 * sandbox_spi_get_emul() - get an emulator for a SPI slave
589 *
590 * This provides a way to attach an emulated SPI device to a particular SPI
591 * slave, so that xfer() operations on the slave will be handled by the
592 * emulator. If a emulator already exists on that chip select it is returned.
593 * Otherwise one is created.
594 *
595 * @state: Sandbox state
596 * @bus: SPI bus requesting the emulator
597 * @slave: SPI slave device requesting the emulator
598 * @emuip: Returns pointer to emulator
599 * @return 0 if OK, -ve on error
600 */
601int sandbox_spi_get_emul(struct sandbox_state *state,
602 struct udevice *bus, struct udevice *slave,
603 struct udevice **emulp);
604
605/* Access the serial operations for a device */
606#define spi_get_ops(dev) ((struct dm_spi_ops *)(dev)->driver->ops)
607#define spi_emul_get_ops(dev) ((struct dm_spi_emul_ops *)(dev)->driver->ops)
608#endif /* CONFIG_DM_SPI */
609
610#endif /* _SPI_H_ */
611
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