2 * Common SPI Interface: Controller-specific definitions
5 * Gerald Van Baren, Custom IDEAS, vanbaren@cideas.com.
7 * SPDX-License-Identifier: GPL-2.0+
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 #define SPI_RX_SLOW BIT(11) /* receive with 1 wire slow */
30 #define SPI_RX_FAST BIT(12) /* receive with 1 wire fast */
31 #define SPI_RX_DUAL BIT(13) /* receive with 2 wires */
32 #define SPI_RX_QUAD BIT(14) /* receive with 4 wires */
34 /* SPI bus connection options - see enum spi_dual_flash */
35 #define SPI_CONN_DUAL_SHARED (1 << 0)
36 #define SPI_CONN_DUAL_SEPARATED (1 << 1)
38 /* Header byte that marks the start of the message */
39 #define SPI_PREAMBLE_END_BYTE 0xec
41 #define SPI_DEFAULT_WORDLEN 8
44 /* TODO(sjg@chromium.org): Remove this and use max_hz from struct spi_slave */
50 * struct dm_spi_platdata - platform data for all SPI slaves
52 * This describes a SPI slave, a child device of the SPI bus. To obtain this
53 * struct from a spi_slave, use dev_get_parent_platdata(dev) or
54 * dev_get_parent_platdata(slave->dev).
56 * This data is immuatable. Each time the device is probed, @max_hz and @mode
57 * will be copied to struct spi_slave.
59 * @cs: Chip select number (0..n-1)
60 * @max_hz: Maximum bus speed that this slave can tolerate
61 * @mode: SPI mode to use for this device (see SPI mode flags)
63 struct dm_spi_slave_platdata {
69 #endif /* CONFIG_DM_SPI */
72 * struct spi_slave - Representation of a SPI slave
74 * For driver model this is the per-child data used by the SPI bus. It can
75 * be accessed using dev_get_parent_priv() on the slave device. The SPI uclass
76 * sets uip per_child_auto_alloc_size to sizeof(struct spi_slave), and the
77 * driver should not override it. Two platform data fields (max_hz and mode)
78 * are copied into this structure to provide an initial value. This allows
79 * them to be changed, since we should never change platform data in drivers.
81 * If not using driver model, drivers are expected to extend this with
82 * controller-specific data.
84 * @dev: SPI slave device
85 * @max_hz: Maximum speed for this slave
86 * @speed: Current bus speed. This is 0 until the bus is first
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 * @mode: SPI mode to use for this slave (see SPI mode flags)
93 * @wordlen: Size of SPI word in number of bits
94 * @max_write_size: If non-zero, the maximum number of bytes which can
95 * be written at once, excluding command bytes.
96 * @memory_map: Address of read-only SPI flash access.
97 * @option: Varies SPI bus options - separate, shared bus.
98 * @flags: Indication of SPI flags.
102 struct udevice *dev; /* struct spi_slave is dev->parentdata */
110 unsigned int wordlen;
111 unsigned int max_write_size;
116 #define SPI_XFER_BEGIN BIT(0) /* Assert CS before transfer */
117 #define SPI_XFER_END BIT(1) /* Deassert CS after transfer */
118 #define SPI_XFER_ONCE (SPI_XFER_BEGIN | SPI_XFER_END)
119 #define SPI_XFER_MMAP BIT(2) /* Memory Mapped start */
120 #define SPI_XFER_MMAP_END BIT(3) /* Memory Mapped End */
121 #define SPI_XFER_U_PAGE BIT(4)
125 * Initialization, must be called once on start up.
127 * TODO: I don't think we really need this.
132 * spi_do_alloc_slave - Allocate a new SPI slave (internal)
134 * Allocate and zero all fields in the spi slave, and set the bus/chip
135 * select. Use the helper macro spi_alloc_slave() to call this.
137 * @offset: Offset of struct spi_slave within slave structure.
138 * @size: Size of slave structure.
139 * @bus: Bus ID of the slave chip.
140 * @cs: Chip select ID of the slave chip on the specified bus.
142 void *spi_do_alloc_slave(int offset, int size, unsigned int bus,
146 * spi_alloc_slave - Allocate a new SPI slave
148 * Allocate and zero all fields in the spi slave, and set the bus/chip
151 * @_struct: Name of structure to allocate (e.g. struct tegra_spi).
152 * This structure must contain a member 'struct spi_slave *slave'.
153 * @bus: Bus ID of the slave chip.
154 * @cs: Chip select ID of the slave chip on the specified bus.
156 #define spi_alloc_slave(_struct, bus, cs) \
157 spi_do_alloc_slave(offsetof(_struct, slave), \
158 sizeof(_struct), bus, cs)
161 * spi_alloc_slave_base - Allocate a new SPI slave with no private data
163 * Allocate and zero all fields in the spi slave, and set the bus/chip
166 * @bus: Bus ID of the slave chip.
167 * @cs: Chip select ID of the slave chip on the specified bus.
169 #define spi_alloc_slave_base(bus, cs) \
170 spi_do_alloc_slave(0, sizeof(struct spi_slave), bus, cs)
173 * Set up communications parameters for a SPI slave.
175 * This must be called once for each slave. Note that this function
176 * usually doesn't touch any actual hardware, it only initializes the
177 * contents of spi_slave so that the hardware can be easily
180 * @bus: Bus ID of the slave chip.
181 * @cs: Chip select ID of the slave chip on the specified bus.
182 * @max_hz: Maximum SCK rate in Hz.
183 * @mode: Clock polarity, clock phase and other parameters.
185 * Returns: A spi_slave reference that can be used in subsequent SPI
186 * calls, or NULL if one or more of the parameters are not supported.
188 struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
189 unsigned int max_hz, unsigned int mode);
192 * Free any memory associated with a SPI slave.
194 * @slave: The SPI slave
196 void spi_free_slave(struct spi_slave *slave);
199 * Claim the bus and prepare it for communication with a given slave.
201 * This must be called before doing any transfers with a SPI slave. It
202 * will enable and initialize any SPI hardware as necessary, and make
203 * sure that the SCK line is in the correct idle state. It is not
204 * allowed to claim the same bus for several slaves without releasing
205 * the bus in between.
207 * @slave: The SPI slave
209 * Returns: 0 if the bus was claimed successfully, or a negative value
212 int spi_claim_bus(struct spi_slave *slave);
215 * Release the SPI bus
217 * This must be called once for every call to spi_claim_bus() after
218 * all transfers have finished. It may disable any SPI hardware as
221 * @slave: The SPI slave
223 void spi_release_bus(struct spi_slave *slave);
226 * Set the word length for SPI transactions
228 * Set the word length (number of bits per word) for SPI transactions.
230 * @slave: The SPI slave
231 * @wordlen: The number of bits in a word
233 * Returns: 0 on success, -1 on failure.
235 int spi_set_wordlen(struct spi_slave *slave, unsigned int wordlen);
240 * This writes "bitlen" bits out the SPI MOSI port and simultaneously clocks
241 * "bitlen" bits in the SPI MISO port. That's just the way SPI works.
243 * The source of the outgoing bits is the "dout" parameter and the
244 * destination of the input bits is the "din" parameter. Note that "dout"
245 * and "din" can point to the same memory location, in which case the
246 * input data overwrites the output data (since both are buffered by
247 * temporary variables, this is OK).
249 * spi_xfer() interface:
250 * @slave: The SPI slave which will be sending/receiving the data.
251 * @bitlen: How many bits to write and read.
252 * @dout: Pointer to a string of bits to send out. The bits are
253 * held in a byte array and are sent MSB first.
254 * @din: Pointer to a string of bits that will be filled in.
255 * @flags: A bitwise combination of SPI_XFER_* flags.
257 * Returns: 0 on success, not 0 on failure
259 int spi_xfer(struct spi_slave *slave, unsigned int bitlen, const void *dout,
260 void *din, unsigned long flags);
262 /* Copy memory mapped data */
263 void spi_flash_copy_mmap(void *data, void *offset, size_t len);
266 * Determine if a SPI chipselect is valid.
267 * This function is provided by the board if the low-level SPI driver
268 * needs it to determine if a given chipselect is actually valid.
270 * Returns: 1 if bus:cs identifies a valid chip on this board, 0
273 int spi_cs_is_valid(unsigned int bus, unsigned int cs);
275 #ifndef CONFIG_DM_SPI
277 * Activate a SPI chipselect.
278 * This function is provided by the board code when using a driver
279 * that can't control its chipselects automatically (e.g.
280 * common/soft_spi.c). When called, it should activate the chip select
281 * to the device identified by "slave".
283 void spi_cs_activate(struct spi_slave *slave);
286 * Deactivate a SPI chipselect.
287 * This function is provided by the board code when using a driver
288 * that can't control its chipselects automatically (e.g.
289 * common/soft_spi.c). When called, it should deactivate the chip
290 * select to the device identified by "slave".
292 void spi_cs_deactivate(struct spi_slave *slave);
295 * Set transfer speed.
296 * This sets a new speed to be applied for next spi_xfer().
297 * @slave: The SPI slave
298 * @hz: The transfer speed
300 void spi_set_speed(struct spi_slave *slave, uint hz);
304 * Write 8 bits, then read 8 bits.
305 * @slave: The SPI slave we're communicating with
306 * @byte: Byte to be written
308 * Returns: The value that was read, or a negative value on error.
310 * TODO: This function probably shouldn't be inlined.
312 static inline int spi_w8r8(struct spi_slave *slave, unsigned char byte)
314 unsigned char dout[2];
315 unsigned char din[2];
321 ret = spi_xfer(slave, 16, dout, din, SPI_XFER_BEGIN | SPI_XFER_END);
322 return ret < 0 ? ret : din[1];
326 * Set up a SPI slave for a particular device tree node
328 * This calls spi_setup_slave() with the correct bus number. Call
329 * spi_free_slave() to free it later.
331 * @param blob: Device tree blob
332 * @param slave_node: Slave node to use
333 * @param spi_node: SPI peripheral node to use
334 * @return pointer to new spi_slave structure
336 struct spi_slave *spi_setup_slave_fdt(const void *blob, int slave_node,
340 * spi_base_setup_slave_fdt() - helper function to set up a SPI slace
342 * This decodes SPI properties from the slave node to determine the
343 * chip select and SPI parameters.
345 * @blob: Device tree blob
346 * @busnum: Bus number to use
347 * @node: Device tree node for the SPI bus
349 struct spi_slave *spi_base_setup_slave_fdt(const void *blob, int busnum,
355 * struct spi_cs_info - Information about a bus chip select
357 * @dev: Connected device, or NULL if none
364 * struct struct dm_spi_ops - Driver model SPI operations
366 * The uclass interface is implemented by all SPI devices which use
371 * Claim the bus and prepare it for communication.
373 * The device provided is the slave device. It's parent controller
374 * will be used to provide the communication.
376 * This must be called before doing any transfers with a SPI slave. It
377 * will enable and initialize any SPI hardware as necessary, and make
378 * sure that the SCK line is in the correct idle state. It is not
379 * allowed to claim the same bus for several slaves without releasing
380 * the bus in between.
382 * @dev: The SPI slave
384 * Returns: 0 if the bus was claimed successfully, or a negative value
387 int (*claim_bus)(struct udevice *dev);
390 * Release the SPI bus
392 * This must be called once for every call to spi_claim_bus() after
393 * all transfers have finished. It may disable any SPI hardware as
396 * @dev: The SPI slave
398 int (*release_bus)(struct udevice *dev);
401 * Set the word length for SPI transactions
403 * Set the word length (number of bits per word) for SPI transactions.
405 * @bus: The SPI slave
406 * @wordlen: The number of bits in a word
408 * Returns: 0 on success, -ve on failure.
410 int (*set_wordlen)(struct udevice *dev, unsigned int wordlen);
415 * This writes "bitlen" bits out the SPI MOSI port and simultaneously
416 * clocks "bitlen" bits in the SPI MISO port. That's just the way SPI
419 * The source of the outgoing bits is the "dout" parameter and the
420 * destination of the input bits is the "din" parameter. Note that
421 * "dout" and "din" can point to the same memory location, in which
422 * case the input data overwrites the output data (since both are
423 * buffered by temporary variables, this is OK).
425 * spi_xfer() interface:
426 * @dev: The slave device to communicate with
427 * @bitlen: How many bits to write and read.
428 * @dout: Pointer to a string of bits to send out. The bits are
429 * held in a byte array and are sent MSB first.
430 * @din: Pointer to a string of bits that will be filled in.
431 * @flags: A bitwise combination of SPI_XFER_* flags.
433 * Returns: 0 on success, not -1 on failure
435 int (*xfer)(struct udevice *dev, unsigned int bitlen, const void *dout,
436 void *din, unsigned long flags);
439 * Set transfer speed.
440 * This sets a new speed to be applied for next spi_xfer().
442 * @hz: The transfer speed
443 * @return 0 if OK, -ve on error
445 int (*set_speed)(struct udevice *bus, uint hz);
448 * Set the SPI mode/flags
450 * It is unclear if we want to set speed and mode together instead
454 * @mode: Requested SPI mode (SPI_... flags)
455 * @return 0 if OK, -ve on error
457 int (*set_mode)(struct udevice *bus, uint mode);
460 * Get information on a chip select
462 * This is only called when the SPI uclass does not know about a
463 * chip select, i.e. it has no attached device. It gives the driver
464 * a chance to allow activity on that chip select even so.
467 * @cs: The chip select (0..n-1)
468 * @info: Returns information about the chip select, if valid.
469 * On entry info->dev is NULL
470 * @return 0 if OK (and @info is set up), -ENODEV if the chip select
471 * is invalid, other -ve value on error
473 int (*cs_info)(struct udevice *bus, uint cs, struct spi_cs_info *info);
476 struct dm_spi_emul_ops {
480 * This writes "bitlen" bits out the SPI MOSI port and simultaneously
481 * clocks "bitlen" bits in the SPI MISO port. That's just the way SPI
482 * works. Here the device is a slave.
484 * The source of the outgoing bits is the "dout" parameter and the
485 * destination of the input bits is the "din" parameter. Note that
486 * "dout" and "din" can point to the same memory location, in which
487 * case the input data overwrites the output data (since both are
488 * buffered by temporary variables, this is OK).
490 * spi_xfer() interface:
491 * @slave: The SPI slave which will be sending/receiving the data.
492 * @bitlen: How many bits to write and read.
493 * @dout: Pointer to a string of bits sent to the device. The
494 * bits are held in a byte array and are sent MSB first.
495 * @din: Pointer to a string of bits that will be sent back to
497 * @flags: A bitwise combination of SPI_XFER_* flags.
499 * Returns: 0 on success, not -1 on failure
501 int (*xfer)(struct udevice *slave, unsigned int bitlen,
502 const void *dout, void *din, unsigned long flags);
506 * spi_find_bus_and_cs() - Find bus and slave devices by number
508 * Given a bus number and chip select, this finds the corresponding bus
509 * device and slave device. Neither device is activated by this function,
510 * although they may have been activated previously.
512 * @busnum: SPI bus number
513 * @cs: Chip select to look for
514 * @busp: Returns bus device
515 * @devp: Return slave device
516 * @return 0 if found, -ENODEV on error
518 int spi_find_bus_and_cs(int busnum, int cs, struct udevice **busp,
519 struct udevice **devp);
522 * spi_get_bus_and_cs() - Find and activate bus and slave devices by number
524 * Given a bus number and chip select, this finds the corresponding bus
525 * device and slave device.
527 * If no such slave exists, and drv_name is not NULL, then a new slave device
528 * is automatically bound on this chip select.
530 * Ths new slave device is probed ready for use with the given speed and mode.
532 * @busnum: SPI bus number
533 * @cs: Chip select to look for
534 * @speed: SPI speed to use for this slave
535 * @mode: SPI mode to use for this slave
536 * @drv_name: Name of driver to attach to this chip select
537 * @dev_name: Name of the new device thus created
538 * @busp: Returns bus device
539 * @devp: Return slave device
540 * @return 0 if found, -ve on error
542 int spi_get_bus_and_cs(int busnum, int cs, int speed, int mode,
543 const char *drv_name, const char *dev_name,
544 struct udevice **busp, struct spi_slave **devp);
547 * spi_chip_select() - Get the chip select for a slave
549 * @return the chip select this slave is attached to
551 int spi_chip_select(struct udevice *slave);
554 * spi_find_chip_select() - Find the slave attached to chip select
556 * @bus: SPI bus to search
557 * @cs: Chip select to look for
558 * @devp: Returns the slave device if found
559 * @return 0 if found, -ENODEV on error
561 int spi_find_chip_select(struct udevice *bus, int cs, struct udevice **devp);
564 * spi_slave_ofdata_to_platdata() - decode standard SPI platform data
566 * This decodes the speed and mode for a slave from a device tree node
568 * @blob: Device tree blob
569 * @node: Node offset to read from
570 * @plat: Place to put the decoded information
572 int spi_slave_ofdata_to_platdata(const void *blob, int node,
573 struct dm_spi_slave_platdata *plat);
576 * spi_cs_info() - Check information on a chip select
578 * This checks a particular chip select on a bus to see if it has a device
579 * attached, or is even valid.
582 * @cs: The chip select (0..n-1)
583 * @info: Returns information about the chip select, if valid
584 * @return 0 if OK (and @info is set up), -ENODEV if the chip select
585 * is invalid, other -ve value on error
587 int spi_cs_info(struct udevice *bus, uint cs, struct spi_cs_info *info);
589 struct sandbox_state;
592 * sandbox_spi_get_emul() - get an emulator for a SPI slave
594 * This provides a way to attach an emulated SPI device to a particular SPI
595 * slave, so that xfer() operations on the slave will be handled by the
596 * emulator. If a emulator already exists on that chip select it is returned.
597 * Otherwise one is created.
599 * @state: Sandbox state
600 * @bus: SPI bus requesting the emulator
601 * @slave: SPI slave device requesting the emulator
602 * @emuip: Returns pointer to emulator
603 * @return 0 if OK, -ve on error
605 int sandbox_spi_get_emul(struct sandbox_state *state,
606 struct udevice *bus, struct udevice *slave,
607 struct udevice **emulp);
610 * Claim the bus and prepare it for communication with a given slave.
612 * This must be called before doing any transfers with a SPI slave. It
613 * will enable and initialize any SPI hardware as necessary, and make
614 * sure that the SCK line is in the correct idle state. It is not
615 * allowed to claim the same bus for several slaves without releasing
616 * the bus in between.
618 * @dev: The SPI slave device
620 * Returns: 0 if the bus was claimed successfully, or a negative value
623 int dm_spi_claim_bus(struct udevice *dev);
626 * Release the SPI bus
628 * This must be called once for every call to dm_spi_claim_bus() after
629 * all transfers have finished. It may disable any SPI hardware as
632 * @slave: The SPI slave device
634 void dm_spi_release_bus(struct udevice *dev);
639 * This writes "bitlen" bits out the SPI MOSI port and simultaneously clocks
640 * "bitlen" bits in the SPI MISO port. That's just the way SPI works.
642 * The source of the outgoing bits is the "dout" parameter and the
643 * destination of the input bits is the "din" parameter. Note that "dout"
644 * and "din" can point to the same memory location, in which case the
645 * input data overwrites the output data (since both are buffered by
646 * temporary variables, this is OK).
648 * dm_spi_xfer() interface:
649 * @dev: The SPI slave device which will be sending/receiving the data.
650 * @bitlen: How many bits to write and read.
651 * @dout: Pointer to a string of bits to send out. The bits are
652 * held in a byte array and are sent MSB first.
653 * @din: Pointer to a string of bits that will be filled in.
654 * @flags: A bitwise combination of SPI_XFER_* flags.
656 * Returns: 0 on success, not 0 on failure
658 int dm_spi_xfer(struct udevice *dev, unsigned int bitlen,
659 const void *dout, void *din, unsigned long flags);
661 /* Access the operations for a SPI device */
662 #define spi_get_ops(dev) ((struct dm_spi_ops *)(dev)->driver->ops)
663 #define spi_emul_get_ops(dev) ((struct dm_spi_emul_ops *)(dev)->driver->ops)
664 #endif /* CONFIG_DM_SPI */