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u-boot/include/spi.h
Simon Glass d0cff03e18 dm: spi: Move slave details to child platdata 
At present we go through various contortions to store the SPI slave's chip
select in its private data. This only exists when the slave is active so
must be set up when it is probed. Until the device is probed we don't
actually know what chip select it will appear on.

However, now that we can support per-child platform data, we can use that
instead. This allows us to set up the chip select when the child is bound,
and avoid the messy contortions.

Unfortunately this is a fairly large change and it seems to be difficult to
break it down further.

Signed-off-by: Simon Glass <sjg@chromium.org>
2015-01-29 17:09:56 -07:00

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/*
* Common SPI Interface: Controller-specific definitions
*
* (C) Copyright 2001
* Gerald Van Baren, Custom IDEAS, vanbaren@cideas.com.
*
* SPDX-License-Identifier: GPL-2.0+
*/
#ifndef _SPI_H_
#define _SPI_H_
/* SPI mode flags */
#define SPI_CPHA 0x01 /* clock phase */
#define SPI_CPOL 0x02 /* 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 0x04 /* CS active high */
#define SPI_LSB_FIRST 0x08 /* per-word bits-on-wire */
#define SPI_3WIRE 0x10 /* SI/SO signals shared */
#define SPI_LOOP 0x20 /* loopback mode */
#define SPI_SLAVE 0x40 /* slave mode */
#define SPI_PREAMBLE 0x80 /* Skip preamble bytes */
/* SPI transfer flags */
#define SPI_XFER_BEGIN 0x01 /* Assert CS before transfer */
#define SPI_XFER_END 0x02 /* Deassert CS after transfer */
#define SPI_XFER_MMAP 0x08 /* Memory Mapped start */
#define SPI_XFER_MMAP_END 0x10 /* Memory Mapped End */
#define SPI_XFER_ONCE (SPI_XFER_BEGIN | SPI_XFER_END)
#define SPI_XFER_U_PAGE (1 << 5)
/* SPI TX operation modes */
#define SPI_OPM_TX_QPP (1 << 0)
#define SPI_OPM_TX_BP (1 << 1)
/* SPI RX operation modes */
#define SPI_OPM_RX_AS (1 << 0)
#define SPI_OPM_RX_DOUT (1 << 1)
#define SPI_OPM_RX_DIO (1 << 2)
#define SPI_OPM_RX_QOF (1 << 3)
#define SPI_OPM_RX_QIOF (1 << 4)
#define SPI_OPM_RX_EXTN (SPI_OPM_RX_AS | SPI_OPM_RX_DOUT | \
SPI_OPM_RX_DIO | SPI_OPM_RX_QOF | \
SPI_OPM_RX_QIOF)
/* SPI bus connection options - see enum spi_dual_flash */
#define SPI_CONN_DUAL_SHARED (1 << 0)
#define SPI_CONN_DUAL_SEPARATED (1 << 1)
/* 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_parentdata() 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
* @mode: SPI mode to use for this slave (see SPI mode flags)
* @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.
* @op_mode_rx: SPI RX operation mode.
* @op_mode_tx: SPI TX operation mode.
* @wordlen: Size of SPI word in number of bits
* @max_write_size: If non-zero, the maximum number of bytes which can
* be written at once, excluding command bytes.
* @memory_map: Address of read-only SPI flash access.
* @option: Varies SPI bus options - separate, shared bus.
* @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 mode;
#else
unsigned int bus;
unsigned int cs;
#endif
u8 op_mode_rx;
u8 op_mode_tx;
unsigned int wordlen;
unsigned int max_write_size;
void *memory_map;
u8 option;
u8 flags;
};
/**
* 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);
/**
* 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];
}
/**
* Set up a SPI slave for a particular device tree node
*
* This calls spi_setup_slave() with the correct bus number. Call
* spi_free_slave() to free it later.
*
* @param blob: Device tree blob
* @param slave_node: Slave node to use
* @param spi_node: SPI peripheral node to use
* @return pointer to new spi_slave structure
*/
struct spi_slave *spi_setup_slave_fdt(const void *blob, int slave_node,
int spi_node);
/**
* spi_base_setup_slave_fdt() - helper function to set up a SPI slace
*
* This decodes SPI properties from the slave node to determine the
* chip select and SPI parameters.
*
* @blob: Device tree blob
* @busnum: Bus number to use
* @node: Device tree node for the SPI bus
*/
struct spi_slave *spi_base_setup_slave_fdt(const void *blob, int busnum,
int node);
#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.
*
* @bus: The SPI slave
*
* Returns: 0 if the bus was claimed successfully, or a negative value
* if it wasn't.
*/
int (*claim_bus)(struct udevice *bus);
/**
* 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.
*
* @bus: The SPI slave
*/
int (*release_bus)(struct udevice *bus);
/**
* 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 *bus, 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(const void *blob, int node,
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);
/* Access the serial operations for a 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_ */
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