diff options
Diffstat (limited to 'include/linux/spi/spi.h')
| -rw-r--r-- | include/linux/spi/spi.h | 137 |
1 files changed, 115 insertions, 22 deletions
diff --git a/include/linux/spi/spi.h b/include/linux/spi/spi.h index d673072346f2..53be3a4c60cb 100644 --- a/include/linux/spi/spi.h +++ b/include/linux/spi/spi.h @@ -23,6 +23,8 @@ #include <linux/scatterlist.h> struct dma_chan; +struct spi_master; +struct spi_transfer; /* * INTERFACES between SPI master-side drivers and SPI infrastructure. @@ -31,6 +33,63 @@ struct dma_chan; extern struct bus_type spi_bus_type; /** + * struct spi_statistics - statistics for spi transfers + * @lock: lock protecting this structure + * + * @messages: number of spi-messages handled + * @transfers: number of spi_transfers handled + * @errors: number of errors during spi_transfer + * @timedout: number of timeouts during spi_transfer + * + * @spi_sync: number of times spi_sync is used + * @spi_sync_immediate: + * number of times spi_sync is executed immediately + * in calling context without queuing and scheduling + * @spi_async: number of times spi_async is used + * + * @bytes: number of bytes transferred to/from device + * @bytes_tx: number of bytes sent to device + * @bytes_rx: number of bytes received from device + * + * @transfer_bytes_histo: + * transfer bytes histogramm + */ +struct spi_statistics { + spinlock_t lock; /* lock for the whole structure */ + + unsigned long messages; + unsigned long transfers; + unsigned long errors; + unsigned long timedout; + + unsigned long spi_sync; + unsigned long spi_sync_immediate; + unsigned long spi_async; + + unsigned long long bytes; + unsigned long long bytes_rx; + unsigned long long bytes_tx; + +#define SPI_STATISTICS_HISTO_SIZE 17 + unsigned long transfer_bytes_histo[SPI_STATISTICS_HISTO_SIZE]; +}; + +void spi_statistics_add_transfer_stats(struct spi_statistics *stats, + struct spi_transfer *xfer, + struct spi_master *master); + +#define SPI_STATISTICS_ADD_TO_FIELD(stats, field, count) \ + do { \ + unsigned long flags; \ + spin_lock_irqsave(&(stats)->lock, flags); \ + (stats)->field += count; \ + spin_unlock_irqrestore(&(stats)->lock, flags); \ + } while (0) + +#define SPI_STATISTICS_INCREMENT_FIELD(stats, field) \ + SPI_STATISTICS_ADD_TO_FIELD(stats, field, 1) + +/** * struct spi_device - Master side proxy for an SPI slave device * @dev: Driver model representation of the device. * @master: SPI controller used with the device. @@ -60,6 +119,8 @@ extern struct bus_type spi_bus_type; * @cs_gpio: gpio number of the chipselect line (optional, -ENOENT when * when not using a GPIO line) * + * @statistics: statistics for the spi_device + * * A @spi_device is used to interchange data between an SPI slave * (usually a discrete chip) and CPU memory. * @@ -98,6 +159,9 @@ struct spi_device { char modalias[SPI_NAME_SIZE]; int cs_gpio; /* chip select gpio */ + /* the statistics */ + struct spi_statistics statistics; + /* * likely need more hooks for more protocol options affecting how * the controller talks to each chip, like: @@ -190,7 +254,7 @@ static inline struct spi_driver *to_spi_driver(struct device_driver *drv) return drv ? container_of(drv, struct spi_driver, driver) : NULL; } -extern int spi_register_driver(struct spi_driver *sdrv); +extern int __spi_register_driver(struct module *owner, struct spi_driver *sdrv); /** * spi_unregister_driver - reverse effect of spi_register_driver @@ -203,6 +267,10 @@ static inline void spi_unregister_driver(struct spi_driver *sdrv) driver_unregister(&sdrv->driver); } +/* use a define to avoid include chaining to get THIS_MODULE */ +#define spi_register_driver(driver) \ + __spi_register_driver(THIS_MODULE, driver) + /** * module_spi_driver() - Helper macro for registering a SPI driver * @__spi_driver: spi_driver struct @@ -296,6 +364,7 @@ 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 * @dma_tx: DMA transmit channel * @dma_rx: DMA receive channel * @dummy_rx: dummy receive buffer for full-duplex devices @@ -356,6 +425,12 @@ struct spi_master { #define SPI_MASTER_MUST_RX BIT(3) /* requires rx */ #define SPI_MASTER_MUST_TX BIT(4) /* requires tx */ + /* + * on some hardware transfer size may be constrained + * the limit may depend on device transfer settings + */ + size_t (*max_transfer_size)(struct spi_device *spi); + /* lock and mutex for SPI bus locking */ spinlock_t bus_lock_spinlock; struct mutex bus_lock_mutex; @@ -452,6 +527,9 @@ struct spi_master { /* gpio chip select */ int *cs_gpios; + /* statistics */ + struct spi_statistics statistics; + /* DMA channels for use with core dmaengine helpers */ struct dma_chan *dma_tx; struct dma_chan *dma_rx; @@ -690,10 +768,15 @@ struct spi_message { void *state; }; +static inline void spi_message_init_no_memset(struct spi_message *m) +{ + INIT_LIST_HEAD(&m->transfers); +} + static inline void spi_message_init(struct spi_message *m) { memset(m, 0, sizeof *m); - INIT_LIST_HEAD(&m->transfers); + spi_message_init_no_memset(m); } static inline void @@ -760,6 +843,15 @@ 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); +static inline size_t +spi_max_transfer_size(struct spi_device *spi) +{ + struct spi_master *master = spi->master; + if (!master->max_transfer_size) + return SIZE_MAX; + return master->max_transfer_size(spi); +} + /*---------------------------------------------------------------------------*/ /* All these synchronous SPI transfer routines are utilities layered @@ -779,8 +871,10 @@ extern int spi_bus_unlock(struct spi_master *master); * @len: data buffer size * Context: can sleep * - * This writes the buffer and returns zero or a negative error code. + * This function writes the buffer @buf. * Callable only from contexts that can sleep. + * + * Return: zero on success, else a negative error code. */ static inline int spi_write(struct spi_device *spi, const void *buf, size_t len) @@ -803,8 +897,10 @@ spi_write(struct spi_device *spi, const void *buf, size_t len) * @len: data buffer size * Context: can sleep * - * This reads the buffer and returns zero or a negative error code. + * This function reads the buffer @buf. * Callable only from contexts that can sleep. + * + * Return: zero on success, else a negative error code. */ static inline int spi_read(struct spi_device *spi, void *buf, size_t len) @@ -831,7 +927,7 @@ spi_read(struct spi_device *spi, void *buf, size_t len) * * For more specific semantics see spi_sync(). * - * It returns zero on success, else a negative error code. + * Return: Return: zero on success, else a negative error code. */ static inline int spi_sync_transfer(struct spi_device *spi, struct spi_transfer *xfers, @@ -855,9 +951,10 @@ extern int spi_write_then_read(struct spi_device *spi, * @cmd: command to be written before data is read back * Context: can sleep * - * This returns the (unsigned) eight bit number returned by the - * device, or else a negative error code. Callable only from - * contexts that can sleep. + * Callable only from contexts that can sleep. + * + * Return: the (unsigned) eight bit number returned by the + * device, or else a negative error code. */ static inline ssize_t spi_w8r8(struct spi_device *spi, u8 cmd) { @@ -876,12 +973,13 @@ static inline ssize_t spi_w8r8(struct spi_device *spi, u8 cmd) * @cmd: command to be written before data is read back * Context: can sleep * - * This returns the (unsigned) sixteen bit number returned by the - * device, or else a negative error code. Callable only from - * contexts that can sleep. - * * The number is returned in wire-order, which is at least sometimes * big-endian. + * + * Callable only from contexts that can sleep. + * + * Return: the (unsigned) sixteen bit number returned by the + * device, or else a negative error code. */ static inline ssize_t spi_w8r16(struct spi_device *spi, u8 cmd) { @@ -900,13 +998,13 @@ static inline ssize_t spi_w8r16(struct spi_device *spi, u8 cmd) * @cmd: command to be written before data is read back * Context: can sleep * - * This returns the (unsigned) sixteen bit number returned by the device in cpu - * endianness, or else a negative error code. Callable only from contexts that - * can sleep. - * * This function is similar to spi_w8r16, with the exception that it will * convert the read 16 bit data word from big-endian to native endianness. * + * Callable only from contexts that can sleep. + * + * Return: the (unsigned) sixteen bit number returned by the device in cpu + * endianness, or else a negative error code. */ static inline ssize_t spi_w8r16be(struct spi_device *spi, u8 cmd) @@ -1037,12 +1135,7 @@ spi_add_device(struct spi_device *spi); extern struct spi_device * spi_new_device(struct spi_master *, struct spi_board_info *); -static inline void -spi_unregister_device(struct spi_device *spi) -{ - if (spi) - device_unregister(&spi->dev); -} +extern void spi_unregister_device(struct spi_device *spi); extern const struct spi_device_id * spi_get_device_id(const struct spi_device *sdev); |