diff options
Diffstat (limited to 'include/spi.h')
| -rw-r--r-- | include/spi.h | 254 |
1 files changed, 251 insertions, 3 deletions
diff --git a/include/spi.h b/include/spi.h index b673be2..89949b1 100644 --- a/include/spi.h +++ b/include/spi.h @@ -54,12 +54,31 @@ #define SPI_DEFAULT_WORDLEN 8 +#ifdef CONFIG_DM_SPI +struct dm_spi_bus { + uint max_hz; +}; + +#endif /* CONFIG_DM_SPI */ + /** * struct spi_slave - Representation of a SPI slave * - * Drivers are expected to extend this with controller-specific data. + * 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. Each SPI + * driver should define this child data in its U_BOOT_DRIVER() definition: + * + * .per_child_auto_alloc_size = sizeof(struct spi_slave), * - * @bus: ID of the bus that the slave is attached to. + * 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. @@ -71,7 +90,13 @@ * @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; +#endif unsigned int cs; u8 op_mode_rx; u8 op_mode_tx; @@ -228,8 +253,9 @@ int spi_xfer(struct spi_slave *slave, unsigned int bitlen, const void *dout, * 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); +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 @@ -255,6 +281,7 @@ void spi_cs_deactivate(struct spi_slave *slave); * @hz: The transfer speed */ void spi_set_speed(struct spi_slave *slave, uint hz); +#endif /** * Write 8 bits, then read 8 bits. @@ -305,4 +332,225 @@ struct spi_slave *spi_setup_slave_fdt(const void *blob, int slave_node, 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); +}; + +/** + * 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_bind_device() - bind a device to a bus's chip select + * + * This binds a new device to an given chip select (which must be unused). + * + * @bus: SPI bus to search + * @cs: Chip select to attach to + * @drv_name: Name of driver to attach to this chip select + * @dev_name: Name of the new device thus created + * @devp: Returns the newly bound device + */ +int spi_bind_device(struct udevice *bus, int cs, const char *drv_name, + const char *dev_name, struct udevice **devp); + +/** + * spi_ofdata_to_platdata() - decode standard SPI platform data + * + * This decodes the speed and mode from a device tree node and puts it into + * the spi_slave structure. + * + * @blob: Device tree blob + * @node: Node offset to read from + * @spi: Place to put the decoded information + */ +int spi_ofdata_to_platdata(const void *blob, int node, struct spi_slave *spi); + +/** + * 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; +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) +#endif /* CONFIG_DM_SPI */ + #endif /* _SPI_H_ */ |