/* SPDX-License-Identifier: GPL-2.0+ */
/*
* Common SPI Interface: Controller-specific definitions
*
* (C) Copyright 2001
* Gerald Van Baren, Custom IDEAS, vanbaren@cideas.com.
*/
#ifndef _SPI_H_
#define _SPI_H_
/* SPI mode flags */
#define SPI_CPHA BIT(0) /* clock phase */
#define SPI_CPOL BIT(1) /* clock polarity */
#define SPI_MODE_0 (0|0) /* (original MicroWire) */
#define SPI_MODE_1 (0|SPI_CPHA)
#define SPI_MODE_2 (SPI_CPOL|0)
#define SPI_MODE_3 (SPI_CPOL|SPI_CPHA)
#define SPI_CS_HIGH BIT(2) /* CS active high */
#define SPI_LSB_FIRST BIT(3) /* per-word bits-on-wire */
#define SPI_3WIRE BIT(4) /* SI/SO signals shared */
#define SPI_LOOP BIT(5) /* loopback mode */
#define SPI_SLAVE BIT(6) /* slave mode */
#define SPI_PREAMBLE BIT(7) /* Skip preamble bytes */
#define SPI_TX_BYTE BIT(8) /* transmit with 1 wire byte */
#define SPI_TX_DUAL BIT(9) /* transmit with 2 wires */
#define SPI_TX_QUAD BIT(10) /* transmit with 4 wires */
#define SPI_RX_SLOW BIT(11) /* receive with 1 wire slow */
#define SPI_RX_DUAL BIT(12) /* receive with 2 wires */
#define SPI_RX_QUAD BIT(13) /* receive with 4 wires */
/* Header byte that marks the start of the message */
#define SPI_PREAMBLE_END_BYTE 0xec
#define SPI_DEFAULT_WORDLEN 8
#ifdef CONFIG_DM_SPI
/* TODO(sjg@chromium.org): Remove this and use max_hz from struct spi_slave */
struct dm_spi_bus {
uint max_hz;
};
/**
* struct dm_spi_platdata - platform data for all SPI slaves
*
* This describes a SPI slave, a child device of the SPI bus. To obtain this
* struct from a spi_slave, use dev_get_parent_platdata(dev) or
* dev_get_parent_platdata(slave->dev).
*
* This data is immuatable. Each time the device is probed, @max_hz and @mode
* will be copied to struct spi_slave.
*
* @cs: Chip select number (0..n-1)
* @max_hz: Maximum bus speed that this slave can tolerate
* @mode: SPI mode to use for this device (see SPI mode flags)
*/
struct dm_spi_slave_platdata {
unsigned int cs;
uint max_hz;
uint mode;
};
#endif /* CONFIG_DM_SPI */
/**
* struct spi_slave - Representation of a SPI slave
*
* For driver model this is the per-child data used by the SPI bus. It can
* be accessed using dev_get_parent_priv() on the slave device. The SPI uclass
* sets uip per_child_auto_alloc_size to sizeof(struct spi_slave), and the
* driver should not override it. Two platform data fields (max_hz and mode)
* are copied into this structure to provide an initial value. This allows
* them to be changed, since we should never change platform data in drivers.
*
* If not using driver model, drivers are expected to extend this with
* controller-specific data.
*
* @dev: SPI slave device
* @max_hz: Maximum speed for this slave
* @speed: Current bus speed. This is 0 until the bus is first
* claimed.
* @bus: ID of the bus that the slave is attached to. For
* driver model this is the sequence number of the SPI
* bus (bus->seq) so does not need to be stored
* @cs: ID of the chip select connected to the slave.
* @mode: SPI mode to use for this slave (see SPI mode flags)
* @wordlen: Size of SPI word in number of bits
* @max_read_size: If non-zero, the maximum number of bytes which can
* be read at once.
* @max_write_size: If non-zero, the maximum number of bytes which can
* be written at once.
* @memory_map: Address of read-only SPI flash access.
* @flags: Indication of SPI flags.
*/
struct spi_slave {
#ifdef CONFIG_DM_SPI
struct udevice *dev; /* struct spi_slave is dev->parentdata */
uint max_hz;
uint speed;
#else
unsigned int bus;
unsigned int cs;
#endif
uint mode;
unsigned int wordlen;
unsigned int max_read_size;
unsigned int max_write_size;
void *memory_map;
u8 flags;
#define SPI_XFER_BEGIN BIT(0) /* Assert CS before transfer */
#define SPI_XFER_END BIT(1) /* Deassert CS after transfer */
#define SPI_XFER_ONCE (SPI_XFER_BEGIN | SPI_XFER_END)
#define SPI_XFER_MMAP BIT(2) /* Memory Mapped start */
#define SPI_XFER_MMAP_END BIT(3) /* Memory Mapped End */
};
/**
* Initialization, must be called once on start up.
*
* TODO: I don't think we really need this.
*/
void spi_init(void);
/**
* spi_do_alloc_slave - Allocate a new SPI slave (internal)
*
* Allocate and zero all fields in the spi slave, and set the bus/chip
* select. Use the helper macro spi_alloc_slave() to call this.
*
* @offset: Offset of struct spi_slave within slave structure.
* @size: Size of slave structure.
* @bus: Bus ID of the slave chip.
* @cs: Chip select ID of the slave chip on the specified bus.
*/
void *spi_do_alloc_slave(int offset, int size, unsigned int bus,
unsigned int cs);
/**
* spi_alloc_slave - Allocate a new SPI slave
*
* Allocate and zero all fields in the spi slave, and set the bus/chip
* select.
*
* @_struct: Name of structure to allocate (e.g. struct tegra_spi).
* This structure must contain a member 'struct spi_slave *slave'.
* @bus: Bus ID of the slave chip.
* @cs: Chip select ID of the slave chip on the specified bus.
*/
#define spi_alloc_slave(_struct, bus, cs) \
spi_do_alloc_slave(offsetof(_struct, slave), \
sizeof(_struct), bus, cs)
/**
* spi_alloc_slave_base - Allocate a new SPI slave with no private data
*
* Allocate and zero all fields in the spi slave, and set the bus/chip
* select.
*
* @bus: Bus ID of the slave chip.
* @cs: Chip select ID of the slave chip on the specified bus.
*/
#define spi_alloc_slave_base(bus, cs) \
spi_do_alloc_slave(0, sizeof(struct spi_slave), bus, cs)
/**
* Set up communications parameters for a SPI slave.
*
* This must be called once for each slave. Note that this function
* usually doesn't touch any actual hardware, it only initializes the
* contents of spi_slave so that the hardware can be easily
* initialized later.
*
* @bus: Bus ID of the slave chip.
* @cs: Chip select ID of the slave chip on the specified bus.
* @max_hz: Maximum SCK rate in Hz.
* @mode: Clock polarity, clock phase and other parameters.
*
* Returns: A spi_slave reference that can be used in subsequent SPI
* calls, or NULL if one or more of the parameters are not supported.
*/
struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
unsigned int max_hz, unsigned int mode);
/**
* Free any memory associated with a SPI slave.
*
* @slave: The SPI slave
*/
void spi_free_slave(struct spi_slave *slave);
/**
* Claim the bus and prepare it for communication with a given slave.
*
* This must be called before doing any transfers with a SPI slave. It
* will enable and initialize any SPI hardware as necessary, and make
* sure that the SCK line is in the correct idle state. It is not
* allowed to claim the same bus for several slaves without releasing
* the bus in between.
*
* @slave: The SPI slave
*
* Returns: 0 if the bus was claimed successfully, or a negative value
* if it wasn't.
*/
int spi_claim_bus(struct spi_slave *slave);
/**
* Release the SPI bus
*
* This must be called once for every call to spi_claim_bus() after
* all transfers have finished. It may disable any SPI hardware as
* appropriate.
*
* @slave: The SPI slave
*/
void spi_release_bus(struct spi_slave *slave);
/**
* Set the word length for SPI transactions
*
* Set the word length (number of bits per word) for SPI transactions.
*
* @slave: The SPI slave
* @wordlen: The number of bits in a word
*
* Returns: 0 on success, -1 on failure.
*/
int spi_set_wordlen(struct spi_slave *slave, unsigned int wordlen);
/**
* SPI transfer
*
* This writes "bitlen" bits out the SPI MOSI port and simultaneously clocks
* "bitlen" bits in the SPI MISO port. That's just the way SPI works.
*
* The source of the outgoing bits is the "dout" parameter and the
* destination of the input bits is the "din" parameter. Note that "dout"
* and "din" can point to the same memory location, in which case the
* input data overwrites the output data (since both are buffered by
* temporary variables, this is OK).
*
* spi_xfer() interface:
* @slave: The SPI slave which will be sending/receiving the data.
* @bitlen: How many bits to write and read.
* @dout: Pointer to a string of bits to send out. The bits are
* held in a byte array and are sent MSB first.
* @din: Pointer to a string of bits that will be filled in.
* @flags: A bitwise combination of SPI_XFER_* flags.
*
* Returns: 0 on success, not 0 on failure
*/
int spi_xfer(struct spi_slave *slave, unsigned int bitlen, const void *dout,
void *din, unsigned long flags);
/* Copy memory mapped data */
void spi_flash_copy_mmap(void *data, void *offset, size_t len);
/**
* Determine if a SPI chipselect is valid.
* This function is provided by the board if the low-level SPI driver
* needs it to determine if a given chipselect is actually valid.
*
* Returns: 1 if bus:cs identifies a valid chip on this board, 0
* otherwise.
*/
int spi_cs_is_valid(unsigned int bus, unsigned int cs);
#ifndef CONFIG_DM_SPI
/**
* Activate a SPI chipselect.
* This function is provided by the board code when using a driver
* that can't control its chipselects automatically (e.g.
* common/soft_spi.c). When called, it should activate the chip select
* to the device identified by "slave".
*/
void spi_cs_activate(struct spi_slave *slave);
/**
* Deactivate a SPI chipselect.
* This function is provided by the board code when using a driver
* that can't control its chipselects automatically (e.g.
* common/soft_spi.c). When called, it should deactivate the chip
* select to the device identified by "slave".
*/
void spi_cs_deactivate(struct spi_slave *slave);
/**
* Set transfer speed.
* This sets a new speed to be applied for next spi_xfer().
* @slave: The SPI slave
* @hz: The transfer speed
*/
void spi_set_speed(struct spi_slave *slave, uint hz);
#endif
/**
* Write 8 bits, then read 8 bits.
* @slave: The SPI slave we're communicating with
* @byte: Byte to be written
*
* Returns: The value that was read, or a negative value on error.
*
* TODO: This function probably shouldn't be inlined.
*/
static inline int spi_w8r8(struct spi_slave *slave, unsigned char byte)
{
unsigned char dout[2];
unsigned char din[2];
int ret;
dout[0] = byte;
dout[1] = 0;
ret = spi_xfer(slave, 16, dout, din, SPI_XFER_BEGIN | SPI_XFER_END);
return ret < 0 ? ret : din[1];
}
#ifdef CONFIG_DM_SPI
/**
* struct spi_cs_info - Information about a bus chip select
*
* @dev: Connected device, or NULL if none
*/
struct spi_cs_info {
struct udevice *dev;
};
/**
* struct struct dm_spi_ops - Driver model SPI operations
*
* The uclass interface is implemented by all SPI devices which use
* driver model.
*/
struct dm_spi_ops {
/**
* Claim the bus and prepare it for communication.
*
* The device provided is the slave device. It's parent controller
* will be used to provide the communication.
*
* This must be called before doing any transfers with a SPI slave. It
* will enable and initialize any SPI hardware as necessary, and make
* sure that the SCK line is in the correct idle state. It is not
* allowed to claim the same bus for several slaves without releasing
* the bus in between.
*
* @dev: The SPI slave
*
* Returns: 0 if the bus was claimed successfully, or a negative value
* if it wasn't.
*/
int (*claim_bus)(struct udevice *dev);
/**
* Release the SPI bus
*
* This must be called once for every call to spi_claim_bus() after
* all transfers have finished. It may disable any SPI hardware as
* appropriate.
*
* @dev: The SPI slave
*/
int (*release_bus)(struct udevice *dev);
/**
* Set the word length for SPI transactions
*
* Set the word length (number of bits per word) for SPI transactions.
*
* @bus: The SPI slave
* @wordlen: The number of bits in a word
*
* Returns: 0 on success, -ve on failure.
*/
int (*set_wordlen)(struct udevice *dev, unsigned int wordlen);
/**
* SPI transfer
*
* This writes "bitlen" bits out the SPI MOSI port and simultaneously
* clocks "bitlen" bits in the SPI MISO port. That's just the way SPI
* works.
*
* The source of the outgoing bits is the "dout" parameter and the
* destination of the input bits is the "din" parameter. Note that
* "dout" and "din" can point to the same memory location, in which
* case the input data overwrites the output data (since both are
* buffered by temporary variables, this is OK).
*
* spi_xfer() interface:
* @dev: The slave device to communicate with
* @bitlen: How many bits to write and read.
* @dout: Pointer to a string of bits to send out. The bits are
* held in a byte array and are sent MSB first.
* @din: Pointer to a string of bits that will be filled in.
* @flags: A bitwise combination of SPI_XFER_* flags.
*
* Returns: 0 on success, not -1 on failure
*/
int (*xfer)(struct udevice *dev, unsigned int bitlen, const void *dout,
void *din, unsigned long flags);
/**
* Set transfer speed.
* This sets a new speed to be applied for next spi_xfer().
* @bus: The SPI bus
* @hz: The transfer speed
* @return 0 if OK, -ve on error
*/
int (*set_speed)(struct udevice *bus, uint hz);
/**
* Set the SPI mode/flags
*
* It is unclear if we want to set speed and mode together instead
* of separately.
*
* @bus: The SPI bus
* @mode: Requested SPI mode (SPI_... flags)
* @return 0 if OK, -ve on error
*/
int (*set_mode)(struct udevice *bus, uint mode);
/**
* Get information on a chip select
*
* This is only called when the SPI uclass does not know about a
* chip select, i.e. it has no attached device. It gives the driver
* a chance to allow activity on that chip select even so.
*
* @bus: The SPI bus
* @cs: The chip select (0..n-1)
* @info: Returns information about the chip select, if valid.
* On entry info->dev is NULL
* @return 0 if OK (and @info is set up), -ENODEV if the chip select
* is invalid, other -ve value on error
*/
int (*cs_info)(struct udevice *bus, uint cs, struct spi_cs_info *info);
};
struct dm_spi_emul_ops {
/**
* SPI transfer
*
* This writes "bitlen" bits out the SPI MOSI port and simultaneously
* clocks "bitlen" bits in the SPI MISO port. That's just the way SPI
* works. Here the device is a slave.
*
* The source of the outgoing bits is the "dout" parameter and the
* destination of the input bits is the "din" parameter. Note that
* "dout" and "din" can point to the same memory location, in which
* case the input data overwrites the output data (since both are
* buffered by temporary variables, this is OK).
*
* spi_xfer() interface:
* @slave: The SPI slave which will be sending/receiving the data.
* @bitlen: How many bits to write and read.
* @dout: Pointer to a string of bits sent to the device. The
* bits are held in a byte array and are sent MSB first.
* @din: Pointer to a string of bits that will be sent back to
* the master.
* @flags: A bitwise combination of SPI_XFER_* flags.
*
* Returns: 0 on success, not -1 on failure
*/
int (*xfer)(struct udevice *slave, unsigned int bitlen,
const void *dout, void *din, unsigned long flags);
};
/**
* spi_find_bus_and_cs() - Find bus and slave devices by number
*
* Given a bus number and chip select, this finds the corresponding bus
* device and slave device. Neither device is activated by this function,
* although they may have been activated previously.
*
* @busnum: SPI bus number
* @cs: Chip select to look for
* @busp: Returns bus device
* @devp: Return slave device
* @return 0 if found, -ENODEV on error
*/
int spi_find_bus_and_cs(int busnum, int cs, struct udevice **busp,
struct udevice **devp);
/**
* spi_get_bus_and_cs() - Find and activate bus and slave devices by number
*
* Given a bus number and chip select, this finds the corresponding bus
* device and slave device.
*
* If no such slave exists, and drv_name is not NULL, then a new slave device
* is automatically bound on this chip select.
*
* Ths new slave device is probed ready for use with the given speed and mode.
*
* @busnum: SPI bus number
* @cs: Chip select to look for
* @speed: SPI speed to use for this slave
* @mode: SPI mode to use for this slave
* @drv_name: Name of driver to attach to this chip select
* @dev_name: Name of the new device thus created
* @busp: Returns bus device
* @devp: Return slave device
* @return 0 if found, -ve on error
*/
int spi_get_bus_and_cs(int busnum, int cs, int speed, int mode,
const char *drv_name, const char *dev_name,
struct udevice **busp, struct spi_slave **devp);
/**
* spi_chip_select() - Get the chip select for a slave
*
* @return the chip select this slave is attached to
*/
int spi_chip_select(struct udevice *slave);
/**
* spi_find_chip_select() - Find the slave attached to chip select
*
* @bus: SPI bus to search
* @cs: Chip select to look for
* @devp: Returns the slave device if found
* @return 0 if found, -ENODEV on error
*/
int spi_find_chip_select(struct udevice *bus, int cs, struct udevice **devp);
/**
* spi_slave_ofdata_to_platdata() - decode standard SPI platform data
*
* This decodes the speed and mode for a slave from a device tree node
*
* @blob: Device tree blob
* @node: Node offset to read from
* @plat: Place to put the decoded information
*/
int spi_slave_ofdata_to_platdata(struct udevice *dev,
struct dm_spi_slave_platdata *plat);
/**
* spi_cs_info() - Check information on a chip select
*
* This checks a particular chip select on a bus to see if it has a device
* attached, or is even valid.
*
* @bus: The SPI bus
* @cs: The chip select (0..n-1)
* @info: Returns information about the chip select, if valid
* @return 0 if OK (and @info is set up), -ENODEV if the chip select
* is invalid, other -ve value on error
*/
int spi_cs_info(struct udevice *bus, uint cs, struct spi_cs_info *info);
struct sandbox_state;
/**
* sandbox_spi_get_emul() - get an emulator for a SPI slave
*
* This provides a way to attach an emulated SPI device to a particular SPI
* slave, so that xfer() operations on the slave will be handled by the
* emulator. If a emulator already exists on that chip select it is returned.
* Otherwise one is created.
*
* @state: Sandbox state
* @bus: SPI bus requesting the emulator
* @slave: SPI slave device requesting the emulator
* @emuip: Returns pointer to emulator
* @return 0 if OK, -ve on error
*/
int sandbox_spi_get_emul(struct sandbox_state *state,
struct udevice *bus, struct udevice *slave,
struct udevice **emulp);
/**
* Claim the bus and prepare it for communication with a given slave.
*
* This must be called before doing any transfers with a SPI slave. It
* will enable and initialize any SPI hardware as necessary, and make
* sure that the SCK line is in the correct idle state. It is not
* allowed to claim the same bus for several slaves without releasing
* the bus in between.
*
* @dev: The SPI slave device
*
* Returns: 0 if the bus was claimed successfully, or a negative value
* if it wasn't.
*/
int dm_spi_claim_bus(struct udevice *dev);
/**
* Release the SPI bus
*
* This must be called once for every call to dm_spi_claim_bus() after
* all transfers have finished. It may disable any SPI hardware as
* appropriate.
*
* @slave: The SPI slave device
*/
void dm_spi_release_bus(struct udevice *dev);
/**
* SPI transfer
*
* This writes "bitlen" bits out the SPI MOSI port and simultaneously clocks
* "bitlen" bits in the SPI MISO port. That's just the way SPI works.
*
* The source of the outgoing bits is the "dout" parameter and the
* destination of the input bits is the "din" parameter. Note that "dout"
* and "din" can point to the same memory location, in which case the
* input data overwrites the output data (since both are buffered by
* temporary variables, this is OK).
*
* dm_spi_xfer() interface:
* @dev: The SPI slave device which will be sending/receiving the data.
* @bitlen: How many bits to write and read.
* @dout: Pointer to a string of bits to send out. The bits are
* held in a byte array and are sent MSB first.
* @din: Pointer to a string of bits that will be filled in.
* @flags: A bitwise combination of SPI_XFER_* flags.
*
* Returns: 0 on success, not 0 on failure
*/
int dm_spi_xfer(struct udevice *dev, unsigned int bitlen,
const void *dout, void *din, unsigned long flags);
/* Access the operations for a SPI device */
#define spi_get_ops(dev) ((struct dm_spi_ops *)(dev)->driver->ops)
#define spi_emul_get_ops(dev) ((struct dm_spi_emul_ops *)(dev)->driver->ops)
#endif /* CONFIG_DM_SPI */
#endif /* _SPI_H_ */