1 /* SPDX-License-Identifier: GPL-2.0-or-later
31  * INTERFACES between SPI master-side drivers and SPI slave protocol handlers,
37  * struct spi_statistics - statistics for spi transfers
38  * @syncp:         seqcount to protect members in this struct for per-cpu udate
39  *                 on 32-bit systems
41  * @messages:      number of spi-messages handled
90 		u64_stats_update_begin(&__lstats->syncp);		\
91 		u64_stats_add(&__lstats->field, count);			\
92 		u64_stats_update_end(&__lstats->syncp);			\
101 		u64_stats_update_begin(&__lstats->syncp);		\
102 		u64_stats_inc(&__lstats->field);			\
103 		u64_stats_update_end(&__lstats->syncp);			\
108  * struct spi_delay - SPI delay information
124  * struct spi_device - Controller side proxy for an SPI slave device
132  * @mode: The spi mode defines how data is clocked out and in.
138  *	like eight or 12 bits are common.  In-memory wordsizes are
147  * @controller_data: Board-specific definitions for controller, such as
195 #define SPI_MODE_KERNEL_MASK	(~(BIT(30) - 1))
203 	struct spi_delay	word_delay; /* Inter-word delay */
215 	 *  - memory packing (12 bit samples into low bits, others zeroed)
216 	 *  - priority
217 	 *  - chipselect delays
218 	 *  - ...
234 	return (spi && get_device(&spi->dev)) ? spi : NULL;  in spi_dev_get()
240 		put_device(&spi->dev);  in spi_dev_put()
246 	return spi->controller_state;  in spi_get_ctldata()
251 	spi->controller_state = state;  in spi_set_ctldata()
258 	dev_set_drvdata(&spi->dev, data);  in spi_set_drvdata()
263 	return dev_get_drvdata(&spi->dev);  in spi_get_drvdata()
269  * struct spi_driver - Host side "protocol" driver
309  * spi_unregister_driver - reverse effect of spi_register_driver
316 		driver_unregister(&sdrv->driver);  in spi_unregister_driver()
326  * module_spi_driver() - Helper macro for registering a SPI driver
338  * struct spi_controller - interface to SPI master or slave controller
341  * @bus_num: board-specific (and often SOC-specific) identifier for a
359  * @devm_allocated: whether the allocation of this struct is devres-managed
378  * @cleanup: frees controller-specific state
388  * @cur_msg: the currently in-flight message
389  * @cur_msg_completion: a completion for the current in-flight message
397  * @last_cs: the last chip_select that is recorded by set_cs, -1 on non chip
427  *                  - return 0 if the transfer is finished,
428  *                  - return 1 if the transfer is still in progress. When
458  * @dummy_rx: dummy receive buffer for full-duplex devices
459  * @dummy_tx: dummy transmit buffer for full-duplex devices
464  *	time snapshot in @spi_transfer->ptp_sts as close as possible to the
465  *	moment in time when @spi_transfer->ptp_sts_word_pre and
466  *	@spi_transfer->ptp_sts_word_post were transmitted.
468  *	close to the driver hand-over as possible.
493 	 * board-specific.  usually that simplifies to being SOC-specific.
495 	 * and one board's schematics might show it using SPI-2.  software
501 	 * might use board-specific GPIOs.
518 #define SPI_BPW_MASK(bits) BIT((bits) - 1)
519 #define SPI_BPW_RANGE_MASK(min, max) GENMASK((max) - 1, (min) - 1)
535 	/* Flag indicating if the allocation of this struct is devres-managed */
583 	 * + For now there's no remove-from-queue operation, or
664 	/* Optimized handlers for SPI memory-like operations. */
703 	return dev_get_drvdata(&ctlr->dev);  in spi_controller_get_devdata()
709 	dev_set_drvdata(&ctlr->dev, data);  in spi_controller_set_devdata()
714 	if (!ctlr || !get_device(&ctlr->dev))  in spi_controller_get()
722 		put_device(&ctlr->dev);  in spi_controller_put()
727 	return IS_ENABLED(CONFIG_SPI_SLAVE) && ctlr->slave;  in spi_controller_is_slave()
806  * struct spi_res - spi resource management structure
809  * @data:    extra data allocated for the specific use-case
811  * this is based on ideas from devres, but focused on life-cycle
820 /*---------------------------------------------------------------------------*/
840  * struct spi_transfer - a read/write buffer pair
841  * @tx_buf: data to be written (dma-safe memory), or NULL
842  * @rx_buf: data to be read (dma-safe memory), or NULL
864  * @effective_speed_hz: the effective SCK-speed that was used to
881  *	purposefully (instead of setting to spi_transfer->len - 1) to denote
882  *	that a transfer-level snapshot taken from within the driver may still
909  * In-memory data values are always in native CPU byte order, translated
910  * from the wire byte order (big-endian except with SPI_LSB_FIRST).  So
914  * When the word size of the SPI transfer is not a power-of-two multiple
915  * of eight bits, those in-memory words include extra bits.  In-memory
916  * words are always seen by protocol drivers as right-justified, so the
930  * stay selected until the next transfer.  On multi-device SPI busses
940  * from device through @tx_nbits and @rx_nbits. In Bi-direction, these
946  * Zero-initialize every field you don't set up explicitly, to
954 	 *   spi_message.is_dma_mapped reports a pre-existing mapping
995  * struct spi_message - one multi-segment SPI transaction
1021  * Zero-initialize every field you don't set up explicitly, to
1037 	 * Some controller drivers (message-at-a-time queue processing)
1039 	 * others (with multi-message pipelines) could need a flag to
1066 	INIT_LIST_HEAD(&m->transfers);  in spi_message_init_no_memset()
1067 	INIT_LIST_HEAD(&m->resources);  in spi_message_init_no_memset()
1079 	list_add_tail(&t->transfer_list, &m->transfers);  in spi_message_add_tail()
1085 	list_del(&t->transfer_list);  in spi_transfer_del()
1091 	return spi_delay_exec(&t->delay, t);  in spi_transfer_delay_exec()
1095  * spi_message_init_with_transfers - Initialize spi_message and append transfers
1115  * structures so long as you don't free them while they're in use.
1148 	struct spi_controller *ctlr = spi->controller;  in spi_max_message_size()
1150 	if (!ctlr->max_message_size)  in spi_max_message_size()
1152 	return ctlr->max_message_size(spi);  in spi_max_message_size()
1158 	struct spi_controller *ctlr = spi->controller;  in spi_max_transfer_size()
1162 	if (ctlr->max_transfer_size)  in spi_max_transfer_size()
1163 		tr_max = ctlr->max_transfer_size(spi);  in spi_max_transfer_size()
1170  * spi_is_bpw_supported - Check if bits per word is supported
1181 	u32 bpw_mask = spi->master->bits_per_word_mask;  in spi_is_bpw_supported()
1189 /*---------------------------------------------------------------------------*/
1198  * struct spi_replaced_transfers - structure describing the spi_transfer
1207  *                      are to get re-inserted
1209  * @inserted_transfers: array of spi_transfers of array-size @inserted,
1225 /*---------------------------------------------------------------------------*/
1234 /*---------------------------------------------------------------------------*/
1247  * spi_sync_transfer - synchronous SPI data transfer
1271  * spi_write - SPI synchronous write
1294  * spi_read - SPI synchronous read
1322  * spi_w8r8 - SPI synchronous 8 bit write followed by 8 bit read
1344  * spi_w8r16 - SPI synchronous 8 bit write followed by 16 bit read
1349  * The number is returned in wire-order, which is at least sometimes
1350  * big-endian.
1369  * spi_w8r16be - SPI synchronous 8 bit write followed by 16 bit big-endian read
1375  * convert the read 16 bit data word from big-endian to native endianness.
1395 /*---------------------------------------------------------------------------*/
1408  * parport adapters, or microcontrollers acting as USB-to-SPI bridges.
1412  * struct spi_board_info - board-specific template for a SPI device
1415  *	data stored there is driver-specific.
1421  *	from the chip datasheet and board-specific signal quality issues.
1436  * be stored in tables of board-specific device descriptors, which are
1478 	 *  - quirks like clock rate mattering when not selected
1492 /* If you're hotplugging an adapter with devices (parport, usb, etc)
1520 	return list_is_last(&xfer->transfer_list, &ctlr->cur_msg->transfers);  in spi_transfer_is_last()