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Diffstat (limited to 'qemu/roms/u-boot/include/spi.h')
| -rw-r--r-- | qemu/roms/u-boot/include/spi.h | 308 |
1 files changed, 308 insertions, 0 deletions
diff --git a/qemu/roms/u-boot/include/spi.h b/qemu/roms/u-boot/include/spi.h new file mode 100644 index 000000000..ffd66478b --- /dev/null +++ b/qemu/roms/u-boot/include/spi.h @@ -0,0 +1,308 @@ +/* + * 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 + +/* 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 */ +#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 + +/** + * struct spi_slave - Representation of a SPI slave + * + * Drivers are expected to extend this with controller-specific data. + * + * @bus: ID of the bus that the slave is attached to. + * @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 { + unsigned int bus; + unsigned int cs; + 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); + +/** + * 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); + +/** + * 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); + +#endif /* _SPI_H_ */ |