#ifndef _SPI_H_
#define _SPI_H_
+/* Controller-specific definitions: */
+
/* SPI mode flags */
#define SPI_CPHA 0x01 /* clock phase */
#define SPI_CPOL 0x02 /* clock polarity */
#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 */
+/* Header byte that marks the start of the message */
+#define SPI_PREAMBLE_END_BYTE 0xec
+
/*-----------------------------------------------------------------------
* Representation of a SPI slave, i.e. what we're communicating with.
*
*
* bus: ID of the bus that the slave is attached to.
* cs: ID of the chip select connected to the slave.
+ * max_write_size: If non-zero, the maximum number of bytes which can
+ * be written at once, excluding command bytes.
*/
struct spi_slave {
unsigned int bus;
unsigned int cs;
+ unsigned int max_write_size;
};
/*-----------------------------------------------------------------------
*/
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.
*
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
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 node SPI peripheral node to use
+ * @param cs Chip select to use
+ * @param max_hz Maximum SCK rate in Hz (0 for default)
+ * @param mode Clock polarity, clock phase and other parameters
+ * @return pointer to new spi_slave structure
+ */
+struct spi_slave *spi_setup_slave_fdt(const void *blob, int node,
+ unsigned int cs, unsigned int max_hz, unsigned int mode);
+
#endif /* _SPI_H_ */