diff options
Diffstat (limited to 'include/linux/spi/spi.h')
| -rw-r--r-- | include/linux/spi/spi.h | 134 |
1 files changed, 97 insertions, 37 deletions
diff --git a/include/linux/spi/spi.h b/include/linux/spi/spi.h index 8497f4747e24..4789f91dae94 100644 --- a/include/linux/spi/spi.h +++ b/include/linux/spi/spi.h @@ -31,9 +31,11 @@ struct spi_transfer; struct spi_controller_mem_ops; struct spi_controller_mem_caps; struct spi_message; +struct spi_offload; +struct spi_offload_config; /* - * INTERFACES between SPI master-side drivers and SPI slave protocol handlers, + * INTERFACES between SPI controller-side drivers and SPI target protocol handlers, * and SPI infrastructure. */ extern const struct bus_type spi_bus_type; @@ -128,19 +130,12 @@ extern void spi_transfer_cs_change_delay_exec(struct spi_message *msg, struct spi_transfer *xfer); /** - * struct spi_device - Controller side proxy for an SPI slave device + * struct spi_device - Controller side proxy for an SPI target device * @dev: Driver model representation of the device. * @controller: SPI controller used with the device. * @max_speed_hz: Maximum clock rate to be used with this chip * (on this board); may be changed by the device's driver. * The spi_transfer.speed_hz can override this for each transfer. - * @chip_select: Array of physical chipselect, spi->chipselect[i] gives - * the corresponding physical CS for logical CS i. - * @mode: The spi mode defines how data is clocked out and in. - * This may be changed by the device's driver. - * The "active low" default for chipselect mode can be overridden - * (by specifying SPI_CS_HIGH) as can the "MSB first" default for - * each word in a transfer (by specifying SPI_LSB_FIRST). * @bits_per_word: Data transfers involve one or more words; word sizes * like eight or 12 bits are common. In-memory wordsizes are * powers of two bytes (e.g. 20 bit samples use 32 bits). @@ -148,6 +143,11 @@ extern void spi_transfer_cs_change_delay_exec(struct spi_message *msg, * default (0) indicating protocol words are eight bit bytes. * The spi_transfer.bits_per_word can override this for each transfer. * @rt: Make the pump thread real time priority. + * @mode: The spi mode defines how data is clocked out and in. + * This may be changed by the device's driver. + * The "active low" default for chipselect mode can be overridden + * (by specifying SPI_CS_HIGH) as can the "MSB first" default for + * each word in a transfer (by specifying SPI_LSB_FIRST). * @irq: Negative, or the number passed to request_irq() to receive * interrupts from this device. * @controller_state: Controller's runtime state @@ -160,8 +160,7 @@ extern void spi_transfer_cs_change_delay_exec(struct spi_message *msg, * the device will bind to the named driver and only the named driver. * Do not set directly, because core frees it; use driver_set_override() to * set or clear it. - * @cs_gpiod: Array of GPIO descriptors of the corresponding chipselect lines - * (optional, NULL when not using a GPIO line) + * @pcpu_statistics: statistics for the spi_device * @word_delay: delay to be inserted between consecutive * words of a transfer * @cs_setup: delay to be introduced by the controller after CS is asserted @@ -169,10 +168,13 @@ extern void spi_transfer_cs_change_delay_exec(struct spi_message *msg, * @cs_inactive: delay to be introduced by the controller after CS is * deasserted. If @cs_change_delay is used from @spi_transfer, then the * two delays will be added up. - * @pcpu_statistics: statistics for the spi_device + * @chip_select: Array of physical chipselect, spi->chipselect[i] gives + * the corresponding physical CS for logical CS i. * @cs_index_mask: Bit mask of the active chipselect(s) in the chipselect array + * @cs_gpiod: Array of GPIO descriptors of the corresponding chipselect lines + * (optional, NULL when not using a GPIO line) * - * A @spi_device is used to interchange data between an SPI slave + * A @spi_device is used to interchange data between an SPI target device * (usually a discrete chip) and CPU memory. * * In @dev, the platform_data is used to hold information about this @@ -185,7 +187,6 @@ struct spi_device { struct device dev; struct spi_controller *controller; u32 max_speed_hz; - u8 chip_select[SPI_CS_CNT_MAX]; u8 bits_per_word; bool rt; #define SPI_NO_TX BIT(31) /* No transmit wire */ @@ -216,23 +217,29 @@ struct spi_device { void *controller_data; char modalias[SPI_NAME_SIZE]; const char *driver_override; - struct gpio_desc *cs_gpiod[SPI_CS_CNT_MAX]; /* Chip select gpio desc */ + + /* The statistics */ + struct spi_statistics __percpu *pcpu_statistics; + struct spi_delay word_delay; /* Inter-word delay */ + /* CS delays */ struct spi_delay cs_setup; struct spi_delay cs_hold; struct spi_delay cs_inactive; - /* The statistics */ - struct spi_statistics __percpu *pcpu_statistics; + u8 chip_select[SPI_CS_CNT_MAX]; - /* Bit mask of the chipselect(s) that the driver need to use from - * the chipselect array.When the controller is capable to handle + /* + * Bit mask of the chipselect(s) that the driver need to use from + * the chipselect array. When the controller is capable to handle * multiple chip selects & memories are connected in parallel * then more than one bit need to be set in cs_index_mask. */ u32 cs_index_mask : SPI_CS_CNT_MAX; + struct gpio_desc *cs_gpiod[SPI_CS_CNT_MAX]; /* Chip select gpio desc */ + /* * Likely need more hooks for more protocol options affecting how * the controller talks to each chip, like: @@ -247,10 +254,7 @@ struct spi_device { static_assert((SPI_MODE_KERNEL_MASK & SPI_MODE_USER_MASK) == 0, "SPI_MODE_USER_MASK & SPI_MODE_KERNEL_MASK must not overlap"); -static inline struct spi_device *to_spi_device(const struct device *dev) -{ - return dev ? container_of(dev, struct spi_device, dev) : NULL; -} +#define to_spi_device(__dev) container_of_const(__dev, struct spi_device, dev) /* Most drivers won't need to care about device refcounting */ static inline struct spi_device *spi_dev_get(struct spi_device *spi) @@ -386,15 +390,15 @@ extern struct spi_device *spi_new_ancillary_device(struct spi_device *spi, u8 ch spi_unregister_driver) /** - * struct spi_controller - interface to SPI master or slave controller + * struct spi_controller - interface to SPI host or target controller * @dev: device interface to this driver * @list: link with the global spi_controller list * @bus_num: board-specific (and often SOC-specific) identifier for a * given SPI controller. * @num_chipselect: chipselects are used to distinguish individual - * SPI slaves, and are numbered from zero to num_chipselects. - * each slave has a chipselect signal, but it's common that not - * every chipselect is connected to a slave. + * SPI targets, and are numbered from zero to num_chipselects. + * each target has a chipselect signal, but it's common that not + * every chipselect is connected to a target. * @dma_alignment: SPI controller constraint on DMA buffers alignment. * @mode_bits: flags understood by this controller driver * @buswidth_override_bits: flags to override for this controller driver @@ -423,9 +427,9 @@ extern struct spi_device *spi_new_ancillary_device(struct spi_device *spi, u8 ch * must fail if an unrecognized or unsupported mode is requested. * It's always safe to call this unless transfers are pending on * the device whose settings are being modified. - * @set_cs_timing: optional hook for SPI devices to request SPI master + * @set_cs_timing: optional hook for SPI devices to request SPI * controller for configuring specific CS setup time, hold time and inactive - * delay interms of clock counts + * delay in terms of clock counts * @transfer: adds a message to the controller's transfer queue. * @cleanup: frees controller-specific state * @can_dma: determine whether this controller supports DMA @@ -496,7 +500,13 @@ extern struct spi_device *spi_new_ancillary_device(struct spi_device *spi, u8 ch * @mem_ops: optimized/dedicated operations for interactions with SPI memory. * This field is optional and should only be implemented if the * controller has native support for memory like operations. + * @get_offload: callback for controllers with offload support to get matching + * offload instance. Implementations should return -ENODEV if no match is + * found. + * @put_offload: release the offload instance acquired by @get_offload. * @mem_caps: controller capabilities for the handling of memory operations. + * @dtr_caps: true if controller has dtr(single/dual transfer rate) capability. + * QSPI based controller should fill this based on controller's capability. * @unprepare_message: undo any work done by prepare_message(). * @target_abort: abort the ongoing transfer request on an SPI target controller * @cs_gpiods: Array of GPIO descriptors to use as chip select lines; one per CS @@ -541,7 +551,7 @@ extern struct spi_device *spi_new_ancillary_device(struct spi_device *spi, u8 ch * * The driver for an SPI controller manages access to those devices through * a queue of spi_message transactions, copying data between CPU memory and - * an SPI slave device. For each such message it queues, it calls the + * an SPI target device. For each such message it queues, it calls the * message's completion function when the transaction completes. */ struct spi_controller { @@ -591,7 +601,7 @@ struct spi_controller { #define SPI_CONTROLLER_NO_TX BIT(2) /* Can't do buffer write */ #define SPI_CONTROLLER_MUST_RX BIT(3) /* Requires rx */ #define SPI_CONTROLLER_MUST_TX BIT(4) /* Requires tx */ -#define SPI_CONTROLLER_GPIO_SS BIT(5) /* GPIO CS must select slave */ +#define SPI_CONTROLLER_GPIO_SS BIT(5) /* GPIO CS must select target device */ #define SPI_CONTROLLER_SUSPENDED BIT(6) /* Currently suspended */ /* * The spi-controller has multi chip select capability and can @@ -658,7 +668,7 @@ struct spi_controller { * + To a given spi_device, message queueing is pure FIFO * * + The controller's main job is to process its message queue, - * selecting a chip (for masters), then transferring data + * selecting a chip (for controllers), then transferring data * + If there are multiple spi_device children, the i/o queue * arbitration algorithm is unspecified (round robin, FIFO, * priority, reservations, preemption, etc) @@ -740,6 +750,13 @@ struct spi_controller { const struct spi_controller_mem_ops *mem_ops; const struct spi_controller_mem_caps *mem_caps; + /* SPI or QSPI controller can set to true if supports SDR/DDR transfer rate */ + bool dtr_caps; + + struct spi_offload *(*get_offload)(struct spi_device *spi, + const struct spi_offload_config *config); + void (*put_offload)(struct spi_offload *offload); + /* GPIO chip select */ struct gpio_desc **cs_gpiods; bool use_gpio_descriptors; @@ -822,7 +839,7 @@ void spi_take_timestamp_post(struct spi_controller *ctlr, /* The SPI driver core manages memory for the spi_controller classdev */ extern struct spi_controller *__spi_alloc_controller(struct device *host, - unsigned int size, bool slave); + unsigned int size, bool target); static inline struct spi_controller *spi_alloc_host(struct device *dev, unsigned int size) @@ -841,7 +858,7 @@ static inline struct spi_controller *spi_alloc_target(struct device *dev, struct spi_controller *__devm_spi_alloc_controller(struct device *dev, unsigned int size, - bool slave); + bool target); static inline struct spi_controller *devm_spi_alloc_host(struct device *dev, unsigned int size) @@ -963,6 +980,8 @@ struct spi_res { * @rx_sg_mapped: If true, the @rx_sg is mapped for DMA * @tx_sg: Scatterlist for transmit, currently not for client use * @rx_sg: Scatterlist for receive, currently not for client use + * @offload_flags: Flags that are only applicable to specialized SPI offload + * transfers. See %SPI_OFFLOAD_XFER_* in spi-offload.h. * @ptp_sts_word_pre: The word (subject to bits_per_word semantics) offset * within @tx_buf for which the SPI device is requesting that the time * snapshot for this transfer begins. Upon completing the SPI transfer, @@ -977,15 +996,16 @@ struct spi_res { * purposefully (instead of setting to spi_transfer->len - 1) to denote * that a transfer-level snapshot taken from within the driver may still * be of higher quality. - * @ptp_sts: Pointer to a memory location held by the SPI slave device where a + * @ptp_sts: Pointer to a memory location held by the SPI target device where a * PTP system timestamp structure may lie. If drivers use PIO or their * hardware has some sort of assist for retrieving exact transfer timing, * they can (and should) assert @ptp_sts_supported and populate this * structure using the ptp_read_system_*ts helper functions. - * The timestamp must represent the time at which the SPI slave device has + * The timestamp must represent the time at which the SPI target device has * processed the word, i.e. the "pre" timestamp should be taken before * transmitting the "pre" word, and the "post" timestamp after receiving * transmit confirmation from the controller for the "post" word. + * @dtr_mode: true if supports double transfer rate. * @timestamped: true if the transfer has been timestamped * @error: Error status logged by SPI controller driver. * @@ -1037,6 +1057,9 @@ struct spi_res { * two should both be set. User can set transfer mode with SPI_NBITS_SINGLE(1x) * SPI_NBITS_DUAL(2x) and SPI_NBITS_QUAD(4x) to support these three transfer. * + * User may also set dtr_mode to true to use dual transfer mode if desired. if + * not, default considered as single transfer mode. + * * The code that submits an spi_message (and its spi_transfers) * to the lower layers is responsible for managing its memory. * Zero-initialize every field you don't set up explicitly, to @@ -1071,6 +1094,7 @@ struct spi_transfer { unsigned tx_nbits:4; unsigned rx_nbits:4; unsigned timestamped:1; + bool dtr_mode; #define SPI_NBITS_SINGLE 0x01 /* 1-bit transfer */ #define SPI_NBITS_DUAL 0x02 /* 2-bit transfer */ #define SPI_NBITS_QUAD 0x04 /* 4-bit transfer */ @@ -1083,6 +1107,9 @@ struct spi_transfer { u32 effective_speed_hz; + /* Use %SPI_OFFLOAD_XFER_* from spi-offload.h */ + unsigned int offload_flags; + unsigned int ptp_sts_word_pre; unsigned int ptp_sts_word_post; @@ -1108,6 +1135,7 @@ struct spi_transfer { * @state: for use by whichever driver currently owns the message * @opt_state: for use by whichever driver currently owns the message * @resources: for resource management when the SPI message is processed + * @offload: (optional) offload instance used by this message * * A @spi_message is used to execute an atomic sequence of data transfers, * each represented by a struct spi_transfer. The sequence is "atomic" @@ -1168,6 +1196,12 @@ struct spi_message { */ void *opt_state; + /* + * Optional offload instance used by this message. This must be set + * by the peripheral driver before calling spi_optimize_message(). + */ + struct spi_offload *offload; + /* List of spi_res resources when the SPI message is processed */ struct list_head resources; }; @@ -1304,6 +1338,32 @@ static inline bool spi_is_bpw_supported(struct spi_device *spi, u32 bpw) } /** + * spi_bpw_to_bytes - Covert bits per word to bytes + * @bpw: Bits per word + * + * This function converts the given @bpw to bytes. The result is always + * power-of-two, e.g., + * + * =============== ================= + * Input (in bits) Output (in bytes) + * =============== ================= + * 5 1 + * 9 2 + * 21 4 + * 37 8 + * =============== ================= + * + * It will return 0 for the 0 input. + * + * Returns: + * Bytes for the given @bpw. + */ +static inline u32 spi_bpw_to_bytes(u32 bpw) +{ + return roundup_pow_of_two(BITS_TO_BYTES(bpw)); +} + +/** * spi_controller_xfer_timeout - Compute a suitable timeout value * @ctlr: SPI device * @xfer: Transfer descriptor @@ -1600,7 +1660,7 @@ struct spi_board_info { * bus_num is board specific and matches the bus_num of some * spi_controller that will probably be registered later. * - * chip_select reflects how this chip is wired to that master; + * chip_select reflects how this chip is wired to that controller; * it's less than num_chipselect. */ u16 bus_num; |