diff options
Diffstat (limited to 'include/spi.h')
| -rw-r--r-- | include/spi.h | 100 |
1 files changed, 52 insertions, 48 deletions
diff --git a/include/spi.h b/include/spi.h index c0dab57..5164d43 100644 --- a/include/spi.h +++ b/include/spi.h @@ -25,29 +25,33 @@ #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_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 */ /* 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. +/** + * 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. - * max_write_size: If non-zero, the maximum number of bytes which can - * be written at once, excluding command bytes. + * @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. + * @memory_map: Address of read-only SPI flash access. */ struct spi_slave { - unsigned int bus; - unsigned int cs; + unsigned int bus; + unsigned int cs; unsigned int max_write_size; + void *memory_map; }; -/*----------------------------------------------------------------------- +/** * Initialization, must be called once on start up. * * TODO: I don't think we really need this. @@ -60,10 +64,10 @@ void spi_init(void); * 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. + * @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); @@ -74,10 +78,10 @@ void *spi_do_alloc_slave(int offset, int size, unsigned int bus, * 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. + * @_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), \ @@ -89,13 +93,13 @@ void *spi_do_alloc_slave(int offset, int size, unsigned int bus, * 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. + * @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 @@ -103,10 +107,10 @@ void *spi_do_alloc_slave(int offset, int size, unsigned int bus, * 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. + * @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. @@ -114,14 +118,14 @@ void *spi_do_alloc_slave(int offset, int size, unsigned int bus, 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 + * @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 @@ -130,25 +134,25 @@ void spi_free_slave(struct spi_slave *slave); * allowed to claim the same bus for several slaves without releasing * the bus in between. * - * slave: The SPI slave + * @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 + * @slave: The SPI slave */ void spi_release_bus(struct spi_slave *slave); -/*----------------------------------------------------------------------- +/** * SPI transfer * * This writes "bitlen" bits out the SPI MOSI port and simultaneously clocks @@ -161,19 +165,19 @@ void spi_release_bus(struct spi_slave *slave); * 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 + * @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. + * @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 + * 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. @@ -183,7 +187,7 @@ int spi_xfer(struct spi_slave *slave, unsigned int bitlen, const void *dout, */ 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. @@ -192,7 +196,7 @@ int spi_cs_is_valid(unsigned int bus, unsigned int cs); */ 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. @@ -201,18 +205,18 @@ void spi_cs_activate(struct spi_slave *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 + * @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 + * @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. * |