diff options
Diffstat (limited to 'include/linux/spi/spi.h')
| -rw-r--r-- | include/linux/spi/spi.h | 217 |
1 files changed, 136 insertions, 81 deletions
diff --git a/include/linux/spi/spi.h b/include/linux/spi/spi.h index 935bd2854ff1..7b2170bfd6e7 100644 --- a/include/linux/spi/spi.h +++ b/include/linux/spi/spi.h @@ -24,13 +24,13 @@ struct dma_chan; struct property_entry; -struct spi_master; +struct spi_controller; struct spi_transfer; struct spi_flash_read_message; /* - * INTERFACES between SPI master-side drivers and SPI infrastructure. - * (There's no SPI slave support for Linux yet...) + * INTERFACES between SPI master-side drivers and SPI slave protocol handlers, + * and SPI infrastructure. */ extern struct bus_type spi_bus_type; @@ -84,7 +84,7 @@ struct spi_statistics { void spi_statistics_add_transfer_stats(struct spi_statistics *stats, struct spi_transfer *xfer, - struct spi_master *master); + struct spi_controller *ctlr); #define SPI_STATISTICS_ADD_TO_FIELD(stats, field, count) \ do { \ @@ -98,13 +98,14 @@ void spi_statistics_add_transfer_stats(struct spi_statistics *stats, SPI_STATISTICS_ADD_TO_FIELD(stats, field, 1) /** - * struct spi_device - Master side proxy for an SPI slave device + * struct spi_device - Controller side proxy for an SPI slave device * @dev: Driver model representation of the device. - * @master: SPI controller used with the device. + * @controller: SPI controller used with the device. + * @master: Copy of controller, for backwards compatibility. * @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: Chipselect, distinguishing chips handled by @master. + * @chip_select: Chipselect, distinguishing chips handled by @controller. * @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 @@ -140,7 +141,8 @@ void spi_statistics_add_transfer_stats(struct spi_statistics *stats, */ struct spi_device { struct device dev; - struct spi_master *master; + struct spi_controller *controller; + struct spi_controller *master; /* compatibility layer */ u32 max_speed_hz; u8 chip_select; u8 bits_per_word; @@ -198,7 +200,7 @@ static inline void spi_dev_put(struct spi_device *spi) put_device(&spi->dev); } -/* ctldata is for the bus_master driver's runtime state */ +/* ctldata is for the bus_controller driver's runtime state */ static inline void *spi_get_ctldata(struct spi_device *spi) { return spi->controller_state; @@ -292,9 +294,9 @@ static inline void spi_unregister_driver(struct spi_driver *sdrv) spi_unregister_driver) /** - * struct spi_master - interface to SPI master controller + * struct spi_controller - interface to SPI master or slave controller * @dev: device interface to this driver - * @list: link with the global spi_master list + * @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 @@ -311,6 +313,7 @@ static inline void spi_unregister_driver(struct spi_driver *sdrv) * @min_speed_hz: Lowest supported transfer speed * @max_speed_hz: Highest supported transfer speed * @flags: other constraints relevant to this driver + * @slave: indicates that this is an SPI slave controller * @max_transfer_size: function that returns the max transfer size for * a &spi_device; may be %NULL, so the default %SIZE_MAX will be used. * @max_message_size: function that returns the max message size for @@ -326,8 +329,8 @@ static inline void spi_unregister_driver(struct spi_driver *sdrv) * the device whose settings are being modified. * @transfer: adds a message to the controller's transfer queue. * @cleanup: frees controller-specific state - * @can_dma: determine whether this master supports DMA - * @queued: whether this master is providing an internal message queue + * @can_dma: determine whether this controller supports DMA + * @queued: whether this controller is providing an internal message queue * @kworker: thread struct for message pump * @kworker_task: pointer to task for message pump kworker thread * @pump_messages: work struct for scheduling work to the message pump @@ -374,6 +377,7 @@ static inline void spi_unregister_driver(struct spi_driver *sdrv) * @handle_err: the subsystem calls the driver to handle an error that occurs * in the generic implementation of transfer_one_message(). * @unprepare_message: undo any work done by prepare_message(). + * @slave_abort: abort the ongoing transfer request on an SPI slave controller * @spi_flash_read: to support spi-controller hardwares that provide * accelerated interface to read from flash devices. * @spi_flash_can_dma: analogous to can_dma() interface, but for @@ -382,7 +386,7 @@ static inline void spi_unregister_driver(struct spi_driver *sdrv) * @cs_gpios: Array of GPIOs to use as chip select lines; one per CS * number. Any individual value may be -ENOENT for CS lines that * are not GPIOs (driven by the SPI controller itself). - * @statistics: statistics for the spi_master + * @statistics: statistics for the spi_controller * @dma_tx: DMA transmit channel * @dma_rx: DMA receive channel * @dummy_rx: dummy receive buffer for full-duplex devices @@ -391,7 +395,7 @@ static inline void spi_unregister_driver(struct spi_driver *sdrv) * what Linux expects, this optional hook can be used to translate * between the two. * - * Each SPI master controller can communicate with one or more @spi_device + * Each SPI controller can communicate with one or more @spi_device * children. These make a small bus, sharing MOSI, MISO and SCK signals * but not chip select signals. Each device may be configured to use a * different clock rate, since those shared signals are ignored unless @@ -402,7 +406,7 @@ static inline void spi_unregister_driver(struct spi_driver *sdrv) * an SPI slave device. For each such message it queues, it calls the * message's completion function when the transaction completes. */ -struct spi_master { +struct spi_controller { struct device dev; struct list_head list; @@ -440,12 +444,16 @@ struct spi_master { /* other constraints relevant to this driver */ u16 flags; -#define SPI_MASTER_HALF_DUPLEX BIT(0) /* can't do full duplex */ -#define SPI_MASTER_NO_RX BIT(1) /* can't do buffer read */ -#define SPI_MASTER_NO_TX BIT(2) /* can't do buffer write */ -#define SPI_MASTER_MUST_RX BIT(3) /* requires rx */ -#define SPI_MASTER_MUST_TX BIT(4) /* requires tx */ -#define SPI_MASTER_GPIO_SS BIT(5) /* GPIO CS must select slave */ +#define SPI_CONTROLLER_HALF_DUPLEX BIT(0) /* can't do full duplex */ +#define SPI_CONTROLLER_NO_RX BIT(1) /* can't do buffer read */ +#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_MASTER_GPIO_SS BIT(5) /* GPIO CS must select slave */ + + /* flag indicating this is an SPI slave controller */ + bool slave; /* * on some hardware transfer / message size may be constrained @@ -480,8 +488,8 @@ struct spi_master { * any other request management * + To a given spi_device, message queueing is pure fifo * - * + The master's main job is to process its message queue, - * selecting a chip then transferring data + * + The controller's main job is to process its message queue, + * selecting a chip (for masters), 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) @@ -494,7 +502,7 @@ struct spi_master { int (*transfer)(struct spi_device *spi, struct spi_message *mesg); - /* called on release() to free memory provided by spi_master */ + /* called on release() to free memory provided by spi_controller */ void (*cleanup)(struct spi_device *spi); /* @@ -504,13 +512,13 @@ struct spi_master { * not modify or store xfer and dma_tx and dma_rx must be set * while the device is prepared. */ - bool (*can_dma)(struct spi_master *master, + bool (*can_dma)(struct spi_controller *ctlr, struct spi_device *spi, struct spi_transfer *xfer); /* * These hooks are for drivers that want to use the generic - * master transfer queueing mechanism. If these are used, the + * controller transfer queueing mechanism. If these are used, the * transfer() function above must NOT be specified by the driver. * Over time we expect SPI drivers to be phased over to this API. */ @@ -531,14 +539,15 @@ struct spi_master { struct completion xfer_completion; size_t max_dma_len; - int (*prepare_transfer_hardware)(struct spi_master *master); - int (*transfer_one_message)(struct spi_master *master, + int (*prepare_transfer_hardware)(struct spi_controller *ctlr); + int (*transfer_one_message)(struct spi_controller *ctlr, struct spi_message *mesg); - int (*unprepare_transfer_hardware)(struct spi_master *master); - int (*prepare_message)(struct spi_master *master, + int (*unprepare_transfer_hardware)(struct spi_controller *ctlr); + int (*prepare_message)(struct spi_controller *ctlr, struct spi_message *message); - int (*unprepare_message)(struct spi_master *master, + int (*unprepare_message)(struct spi_controller *ctlr, struct spi_message *message); + int (*slave_abort)(struct spi_controller *ctlr); int (*spi_flash_read)(struct spi_device *spi, struct spi_flash_read_message *msg); bool (*spi_flash_can_dma)(struct spi_device *spi, @@ -550,9 +559,9 @@ struct spi_master { * of transfer_one_message() provied by the core. */ void (*set_cs)(struct spi_device *spi, bool enable); - int (*transfer_one)(struct spi_master *master, struct spi_device *spi, + int (*transfer_one)(struct spi_controller *ctlr, struct spi_device *spi, struct spi_transfer *transfer); - void (*handle_err)(struct spi_master *master, + void (*handle_err)(struct spi_controller *ctlr, struct spi_message *message); /* gpio chip select */ @@ -569,57 +578,78 @@ struct spi_master { void *dummy_rx; void *dummy_tx; - int (*fw_translate_cs)(struct spi_master *master, unsigned cs); + int (*fw_translate_cs)(struct spi_controller *ctlr, unsigned cs); }; -static inline void *spi_master_get_devdata(struct spi_master *master) +static inline void *spi_controller_get_devdata(struct spi_controller *ctlr) { - return dev_get_drvdata(&master->dev); + return dev_get_drvdata(&ctlr->dev); } -static inline void spi_master_set_devdata(struct spi_master *master, void *data) +static inline void spi_controller_set_devdata(struct spi_controller *ctlr, + void *data) { - dev_set_drvdata(&master->dev, data); + dev_set_drvdata(&ctlr->dev, data); } -static inline struct spi_master *spi_master_get(struct spi_master *master) +static inline struct spi_controller *spi_controller_get(struct spi_controller *ctlr) { - if (!master || !get_device(&master->dev)) + if (!ctlr || !get_device(&ctlr->dev)) return NULL; - return master; + return ctlr; +} + +static inline void spi_controller_put(struct spi_controller *ctlr) +{ + if (ctlr) + put_device(&ctlr->dev); } -static inline void spi_master_put(struct spi_master *master) +static inline bool spi_controller_is_slave(struct spi_controller *ctlr) { - if (master) - put_device(&master->dev); + return IS_ENABLED(CONFIG_SPI_SLAVE) && ctlr->slave; } /* PM calls that need to be issued by the driver */ -extern int spi_master_suspend(struct spi_master *master); -extern int spi_master_resume(struct spi_master *master); +extern int spi_controller_suspend(struct spi_controller *ctlr); +extern int spi_controller_resume(struct spi_controller *ctlr); /* Calls the driver make to interact with the message queue */ -extern struct spi_message *spi_get_next_queued_message(struct spi_master *master); -extern void spi_finalize_current_message(struct spi_master *master); -extern void spi_finalize_current_transfer(struct spi_master *master); +extern struct spi_message *spi_get_next_queued_message(struct spi_controller *ctlr); +extern void spi_finalize_current_message(struct spi_controller *ctlr); +extern void spi_finalize_current_transfer(struct spi_controller *ctlr); -/* the spi driver core manages memory for the spi_master classdev */ -extern struct spi_master * -spi_alloc_master(struct device *host, unsigned size); +/* 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); -extern int spi_register_master(struct spi_master *master); -extern int devm_spi_register_master(struct device *dev, - struct spi_master *master); -extern void spi_unregister_master(struct spi_master *master); +static inline struct spi_controller *spi_alloc_master(struct device *host, + unsigned int size) +{ + return __spi_alloc_controller(host, size, false); +} -extern struct spi_master *spi_busnum_to_master(u16 busnum); +static inline struct spi_controller *spi_alloc_slave(struct device *host, + unsigned int size) +{ + if (!IS_ENABLED(CONFIG_SPI_SLAVE)) + return NULL; + + return __spi_alloc_controller(host, size, true); +} + +extern int spi_register_controller(struct spi_controller *ctlr); +extern int devm_spi_register_controller(struct device *dev, + struct spi_controller *ctlr); +extern void spi_unregister_controller(struct spi_controller *ctlr); + +extern struct spi_controller *spi_busnum_to_master(u16 busnum); /* * SPI resource management while processing a SPI message */ -typedef void (*spi_res_release_t)(struct spi_master *master, +typedef void (*spi_res_release_t)(struct spi_controller *ctlr, struct spi_message *msg, void *res); @@ -644,7 +674,7 @@ extern void *spi_res_alloc(struct spi_device *spi, extern void spi_res_add(struct spi_message *message, void *res); extern void spi_res_free(void *res); -extern void spi_res_release(struct spi_master *master, +extern void spi_res_release(struct spi_controller *ctlr, struct spi_message *message); /*---------------------------------------------------------------------------*/ @@ -828,7 +858,7 @@ struct spi_message { /* for optional use by whatever driver currently owns the * spi_message ... between calls to spi_async and then later - * complete(), that's the spi_master controller driver. + * complete(), that's the spi_controller controller driver. */ struct list_head queue; void *state; @@ -912,25 +942,27 @@ extern int spi_setup(struct spi_device *spi); extern int spi_async(struct spi_device *spi, struct spi_message *message); extern int spi_async_locked(struct spi_device *spi, struct spi_message *message); +extern int spi_slave_abort(struct spi_device *spi); static inline size_t spi_max_message_size(struct spi_device *spi) { - struct spi_master *master = spi->master; - if (!master->max_message_size) + struct spi_controller *ctlr = spi->controller; + + if (!ctlr->max_message_size) return SIZE_MAX; - return master->max_message_size(spi); + return ctlr->max_message_size(spi); } static inline size_t spi_max_transfer_size(struct spi_device *spi) { - struct spi_master *master = spi->master; + struct spi_controller *ctlr = spi->controller; size_t tr_max = SIZE_MAX; size_t msg_max = spi_max_message_size(spi); - if (master->max_transfer_size) - tr_max = master->max_transfer_size(spi); + if (ctlr->max_transfer_size) + tr_max = ctlr->max_transfer_size(spi); /* transfer size limit must not be greater than messsage size limit */ return min(tr_max, msg_max); @@ -941,7 +973,7 @@ spi_max_transfer_size(struct spi_device *spi) /* SPI transfer replacement methods which make use of spi_res */ struct spi_replaced_transfers; -typedef void (*spi_replaced_release_t)(struct spi_master *master, +typedef void (*spi_replaced_release_t)(struct spi_controller *ctlr, struct spi_message *msg, struct spi_replaced_transfers *res); /** @@ -985,7 +1017,7 @@ extern struct spi_replaced_transfers *spi_replace_transfers( /* SPI transfer transformation methods */ -extern int spi_split_transfers_maxsize(struct spi_master *master, +extern int spi_split_transfers_maxsize(struct spi_controller *ctlr, struct spi_message *msg, size_t maxsize, gfp_t gfp); @@ -999,8 +1031,8 @@ extern int spi_split_transfers_maxsize(struct spi_master *master, extern int spi_sync(struct spi_device *spi, struct spi_message *message); extern int spi_sync_locked(struct spi_device *spi, struct spi_message *message); -extern int spi_bus_lock(struct spi_master *master); -extern int spi_bus_unlock(struct spi_master *master); +extern int spi_bus_lock(struct spi_controller *ctlr); +extern int spi_bus_unlock(struct spi_controller *ctlr); /** * spi_sync_transfer - synchronous SPI data transfer @@ -1185,9 +1217,9 @@ struct spi_flash_read_message { /* SPI core interface for flash read support */ static inline bool spi_flash_read_supported(struct spi_device *spi) { - return spi->master->spi_flash_read && - (!spi->master->flash_read_supported || - spi->master->flash_read_supported(spi)); + return spi->controller->spi_flash_read && + (!spi->controller->flash_read_supported || + spi->controller->flash_read_supported(spi)); } int spi_flash_read(struct spi_device *spi, @@ -1220,7 +1252,7 @@ int spi_flash_read(struct spi_device *spi, * @irq: Initializes spi_device.irq; depends on how the board is wired. * @max_speed_hz: Initializes spi_device.max_speed_hz; based on limits * from the chip datasheet and board-specific signal quality issues. - * @bus_num: Identifies which spi_master parents the spi_device; unused + * @bus_num: Identifies which spi_controller parents the spi_device; unused * by spi_new_device(), and otherwise depends on board wiring. * @chip_select: Initializes spi_device.chip_select; depends on how * the board is wired. @@ -1261,7 +1293,7 @@ struct spi_board_info { /* bus_num is board specific and matches the bus_num of some - * spi_master that will probably be registered later. + * spi_controller that will probably be registered later. * * chip_select reflects how this chip is wired to that master; * it's less than num_chipselect. @@ -1295,7 +1327,7 @@ spi_register_board_info(struct spi_board_info const *info, unsigned n) /* If you're hotplugging an adapter with devices (parport, usb, etc) * use spi_new_device() to describe each device. You can also call * spi_unregister_device() to start making that device vanish, but - * normally that would be handled by spi_unregister_master(). + * normally that would be handled by spi_unregister_controller(). * * You can also use spi_alloc_device() and spi_add_device() to use a two * stage registration sequence for each spi_device. This gives the caller @@ -1304,13 +1336,13 @@ spi_register_board_info(struct spi_board_info const *info, unsigned n) * be defined using the board info. */ extern struct spi_device * -spi_alloc_device(struct spi_master *master); +spi_alloc_device(struct spi_controller *ctlr); extern int spi_add_device(struct spi_device *spi); extern struct spi_device * -spi_new_device(struct spi_master *, struct spi_board_info *); +spi_new_device(struct spi_controller *, struct spi_board_info *); extern void spi_unregister_device(struct spi_device *spi); @@ -1318,9 +1350,32 @@ extern const struct spi_device_id * spi_get_device_id(const struct spi_device *sdev); static inline bool -spi_transfer_is_last(struct spi_master *master, struct spi_transfer *xfer) +spi_transfer_is_last(struct spi_controller *ctlr, struct spi_transfer *xfer) { - return list_is_last(&xfer->transfer_list, &master->cur_msg->transfers); + return list_is_last(&xfer->transfer_list, &ctlr->cur_msg->transfers); } + +/* Compatibility layer */ +#define spi_master spi_controller + +#define SPI_MASTER_HALF_DUPLEX SPI_CONTROLLER_HALF_DUPLEX +#define SPI_MASTER_NO_RX SPI_CONTROLLER_NO_RX +#define SPI_MASTER_NO_TX SPI_CONTROLLER_NO_TX +#define SPI_MASTER_MUST_RX SPI_CONTROLLER_MUST_RX +#define SPI_MASTER_MUST_TX SPI_CONTROLLER_MUST_TX + +#define spi_master_get_devdata(_ctlr) spi_controller_get_devdata(_ctlr) +#define spi_master_set_devdata(_ctlr, _data) \ + spi_controller_set_devdata(_ctlr, _data) +#define spi_master_get(_ctlr) spi_controller_get(_ctlr) +#define spi_master_put(_ctlr) spi_controller_put(_ctlr) +#define spi_master_suspend(_ctlr) spi_controller_suspend(_ctlr) +#define spi_master_resume(_ctlr) spi_controller_resume(_ctlr) + +#define spi_register_master(_ctlr) spi_register_controller(_ctlr) +#define devm_spi_register_master(_dev, _ctlr) \ + devm_spi_register_controller(_dev, _ctlr) +#define spi_unregister_master(_ctlr) spi_unregister_controller(_ctlr) + #endif /* __LINUX_SPI_H */ |