diff options
Diffstat (limited to 'include/linux/spi/spi.h')
| -rw-r--r-- | include/linux/spi/spi.h | 169 |
1 files changed, 98 insertions, 71 deletions
diff --git a/include/linux/spi/spi.h b/include/linux/spi/spi.h index d361ba26203b..e6c73d5ff1a8 100644 --- a/include/linux/spi/spi.h +++ b/include/linux/spi/spi.h @@ -17,6 +17,7 @@ #include <uapi/linux/spi/spi.h> #include <linux/acpi.h> +#include <linux/u64_stats_sync.h> struct dma_chan; struct software_node; @@ -34,7 +35,8 @@ extern struct bus_type spi_bus_type; /** * struct spi_statistics - statistics for spi transfers - * @lock: lock protecting this structure + * @syncp: seqcount to protect members in this struct for per-cpu udate + * on 32-bit systems * * @messages: number of spi-messages handled * @transfers: number of spi_transfers handled @@ -59,37 +61,48 @@ extern struct bus_type spi_bus_type; * maxsize limit */ struct spi_statistics { - spinlock_t lock; /* lock for the whole structure */ + struct u64_stats_sync syncp; - unsigned long messages; - unsigned long transfers; - unsigned long errors; - unsigned long timedout; + u64_stats_t messages; + u64_stats_t transfers; + u64_stats_t errors; + u64_stats_t timedout; - unsigned long spi_sync; - unsigned long spi_sync_immediate; - unsigned long spi_async; + u64_stats_t spi_sync; + u64_stats_t spi_sync_immediate; + u64_stats_t spi_async; - unsigned long long bytes; - unsigned long long bytes_rx; - unsigned long long bytes_tx; + u64_stats_t bytes; + u64_stats_t bytes_rx; + u64_stats_t bytes_tx; #define SPI_STATISTICS_HISTO_SIZE 17 - unsigned long transfer_bytes_histo[SPI_STATISTICS_HISTO_SIZE]; + u64_stats_t transfer_bytes_histo[SPI_STATISTICS_HISTO_SIZE]; - unsigned long transfers_split_maxsize; + u64_stats_t transfers_split_maxsize; }; -#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); \ +#define SPI_STATISTICS_ADD_TO_FIELD(pcpu_stats, field, count) \ + do { \ + struct spi_statistics *__lstats; \ + get_cpu(); \ + __lstats = this_cpu_ptr(pcpu_stats); \ + u64_stats_update_begin(&__lstats->syncp); \ + u64_stats_add(&__lstats->field, count); \ + u64_stats_update_end(&__lstats->syncp); \ + put_cpu(); \ } while (0) -#define SPI_STATISTICS_INCREMENT_FIELD(stats, field) \ - SPI_STATISTICS_ADD_TO_FIELD(stats, field, 1) +#define SPI_STATISTICS_INCREMENT_FIELD(pcpu_stats, field) \ + do { \ + struct spi_statistics *__lstats; \ + get_cpu(); \ + __lstats = this_cpu_ptr(pcpu_stats); \ + u64_stats_update_begin(&__lstats->syncp); \ + u64_stats_inc(&__lstats->field); \ + u64_stats_update_end(&__lstats->syncp); \ + put_cpu(); \ + } while (0) /** * struct spi_delay - SPI delay information @@ -149,7 +162,7 @@ extern int spi_delay_exec(struct spi_delay *_delay, struct spi_transfer *xfer); * @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. - * @statistics: statistics for the spi_device + * @pcpu_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. @@ -163,13 +176,13 @@ extern int spi_delay_exec(struct spi_delay *_delay, struct spi_transfer *xfer); struct spi_device { struct device dev; struct spi_controller *controller; - struct spi_controller *master; /* compatibility layer */ + struct spi_controller *master; /* Compatibility layer */ u32 max_speed_hz; u8 chip_select; u8 bits_per_word; bool rt; -#define SPI_NO_TX BIT(31) /* no transmit wire */ -#define SPI_NO_RX BIT(30) /* no receive wire */ +#define SPI_NO_TX BIT(31) /* No transmit wire */ +#define SPI_NO_RX BIT(30) /* No receive wire */ /* * All bits defined above should be covered by SPI_MODE_KERNEL_MASK. * The SPI_MODE_KERNEL_MASK has the SPI_MODE_USER_MASK counterpart, @@ -186,15 +199,15 @@ struct spi_device { void *controller_data; char modalias[SPI_NAME_SIZE]; const char *driver_override; - struct gpio_desc *cs_gpiod; /* chip select gpio desc */ - struct spi_delay word_delay; /* inter-word delay */ + struct gpio_desc *cs_gpiod; /* Chip select gpio desc */ + 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 statistics; + /* The statistics */ + struct spi_statistics __percpu *pcpu_statistics; /* * likely need more hooks for more protocol options affecting how @@ -215,7 +228,7 @@ static inline struct spi_device *to_spi_device(struct device *dev) return dev ? container_of(dev, struct spi_device, dev) : NULL; } -/* most drivers won't need to care about device refcounting */ +/* Most drivers won't need to care about device refcounting */ static inline struct spi_device *spi_dev_get(struct spi_device *spi) { return (spi && get_device(&spi->dev)) ? spi : NULL; @@ -238,7 +251,7 @@ static inline void spi_set_ctldata(struct spi_device *spi, void *state) spi->controller_state = state; } -/* device driver data */ +/* Device driver data */ static inline void spi_set_drvdata(struct spi_device *spi, void *data) { @@ -305,7 +318,7 @@ static inline void spi_unregister_driver(struct spi_driver *sdrv) extern struct spi_device *spi_new_ancillary_device(struct spi_device *spi, u8 chip_select); -/* use a define to avoid include chaining to get THIS_MODULE */ +/* Use a define to avoid include chaining to get THIS_MODULE */ #define spi_register_driver(driver) \ __spi_register_driver(THIS_MODULE, driver) @@ -370,10 +383,14 @@ extern struct spi_device *spi_new_ancillary_device(struct spi_device *spi, u8 ch * @pump_messages: work struct for scheduling work to the message pump * @queue_lock: spinlock to syncronise access to message queue * @queue: message queue - * @idling: the device is entering idle state * @cur_msg: the currently in-flight message - * @cur_msg_prepared: spi_prepare_message was called for the currently - * in-flight message + * @cur_msg_completion: a completion for the current in-flight message + * @cur_msg_incomplete: Flag used internally to opportunistically skip + * the @cur_msg_completion. This flag is used to check if the driver has + * already called spi_finalize_current_message(). + * @cur_msg_need_completion: Flag used internally to opportunistically skip + * the @cur_msg_completion. This flag is used to signal the context that + * is running spi_finalize_current_message() that it needs to complete() * @cur_msg_mapped: message has been mapped for DMA * @last_cs: the last chip_select that is recorded by set_cs, -1 on non chip * selected @@ -433,7 +450,7 @@ extern struct spi_device *spi_new_ancillary_device(struct spi_device *spi, u8 ch * @max_native_cs: When cs_gpiods is used, and this field is filled in, * spi_register_controller() will validate all native CS (including the * unused native CS) against this value. - * @statistics: statistics for the spi_controller + * @pcpu_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 @@ -450,6 +467,8 @@ extern struct spi_device *spi_new_ancillary_device(struct spi_device *spi, u8 ch * @irq_flags: Interrupt enable state during PTP system timestamping * @fallback: fallback to pio if dma transfer return failure with * SPI_TRANS_FAIL_NO_START. + * @queue_empty: signal green light for opportunistically skipping the queue + * for spi_sync transfers. * * Each SPI controller can communicate with one or more @spi_device * children. These make a small bus, sharing MOSI, MISO and SCK signals @@ -467,7 +486,7 @@ struct spi_controller { struct list_head list; - /* other than negative (== assign one dynamically), bus_num is fully + /* Other than negative (== assign one dynamically), bus_num is fully * board-specific. usually that simplifies to being SOC-specific. * example: one SOC has three SPI controllers, numbered 0..2, * and one board's schematics might show it using SPI-2. software @@ -480,7 +499,7 @@ struct spi_controller { */ u16 num_chipselect; - /* some SPI controllers pose alignment requirements on DMAable + /* Some SPI controllers pose alignment requirements on DMAable * buffers; let protocol drivers know about these requirements. */ u16 dma_alignment; @@ -491,29 +510,29 @@ struct spi_controller { /* spi_device.mode flags override flags for this controller */ u32 buswidth_override_bits; - /* bitmask of supported bits_per_word for transfers */ + /* Bitmask of supported bits_per_word for transfers */ u32 bits_per_word_mask; #define SPI_BPW_MASK(bits) BIT((bits) - 1) #define SPI_BPW_RANGE_MASK(min, max) GENMASK((max) - 1, (min) - 1) - /* limits on transfer speed */ + /* Limits on transfer speed */ u32 min_speed_hz; u32 max_speed_hz; - /* other constraints relevant to this driver */ + /* Other constraints relevant to this driver */ u16 flags; -#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_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 if the allocation of this struct is devres-managed */ + /* Flag indicating if the allocation of this struct is devres-managed */ bool devm_allocated; - /* flag indicating this is an SPI slave controller */ + /* Flag indicating this is an SPI slave controller */ bool slave; /* @@ -529,11 +548,11 @@ struct spi_controller { /* Used to avoid adding the same CS twice */ struct mutex add_lock; - /* lock and mutex for SPI bus locking */ + /* Lock and mutex for SPI bus locking */ spinlock_t bus_lock_spinlock; struct mutex bus_lock_mutex; - /* flag indicating that the SPI bus is locked for exclusive use */ + /* Flag indicating that the SPI bus is locked for exclusive use */ bool bus_lock_flag; /* Setup mode and clock, etc (spi driver may call many times). @@ -554,7 +573,7 @@ struct spi_controller { */ int (*set_cs_timing)(struct spi_device *spi); - /* bidirectional bulk transfers + /* Bidirectional bulk transfers * * + The transfer() method may not sleep; its main role is * just to add the message to the queue. @@ -576,7 +595,7 @@ struct spi_controller { int (*transfer)(struct spi_device *spi, struct spi_message *mesg); - /* called on release() to free memory provided by spi_controller */ + /* Called on release() to free memory provided by spi_controller */ void (*cleanup)(struct spi_device *spi); /* @@ -603,12 +622,13 @@ struct spi_controller { spinlock_t queue_lock; struct list_head queue; struct spi_message *cur_msg; - bool idling; + struct completion cur_msg_completion; + bool cur_msg_incomplete; + bool cur_msg_need_completion; bool busy; bool running; bool rt; bool auto_runtime_pm; - bool cur_msg_prepared; bool cur_msg_mapped; char last_cs; bool last_cs_mode_high; @@ -646,14 +666,14 @@ struct spi_controller { s8 unused_native_cs; s8 max_native_cs; - /* statistics */ - struct spi_statistics statistics; + /* Statistics */ + struct spi_statistics __percpu *pcpu_statistics; /* DMA channels for use with core dmaengine helpers */ struct dma_chan *dma_tx; struct dma_chan *dma_rx; - /* dummy data for full duplex devices */ + /* Dummy data for full duplex devices */ void *dummy_rx; void *dummy_tx; @@ -667,6 +687,9 @@ struct spi_controller { /* Interrupt enable state during PTP system timestamping */ unsigned long irq_flags; + + /* Flag for enabling opportunistic skipping of the queue in spi_sync */ + bool queue_empty; }; static inline void *spi_controller_get_devdata(struct spi_controller *ctlr) @@ -715,7 +738,7 @@ void spi_take_timestamp_post(struct spi_controller *ctlr, struct spi_transfer *xfer, size_t progress, bool irqs_off); -/* the spi driver core manages memory for the spi_controller classdev */ +/* 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); @@ -785,7 +808,7 @@ typedef void (*spi_res_release_t)(struct spi_controller *ctlr, struct spi_res { struct list_head entry; spi_res_release_t release; - unsigned long long data[]; /* guarantee ull alignment */ + unsigned long long data[]; /* Guarantee ull alignment */ }; /*---------------------------------------------------------------------------*/ @@ -918,7 +941,7 @@ struct spi_res { * and its transfers, ignore them until its completion callback. */ struct spi_transfer { - /* it's ok if tx_buf == rx_buf (right?) + /* It's ok if tx_buf == rx_buf (right?) * for MicroWire, one buffer must be null * buffers must work with dma_*map_single() calls, unless * spi_message.is_dma_mapped reports a pre-existing mapping @@ -975,6 +998,7 @@ struct spi_transfer { * @queue: for use by whichever driver currently owns the message * @state: for use by whichever driver currently owns the message * @resources: for resource management when the spi message is processed + * @prepared: spi_prepare_message was called for the 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" @@ -1008,22 +1032,25 @@ struct spi_message { * tell them about such special cases. */ - /* completion is reported through a callback */ + /* Completion is reported through a callback */ void (*complete)(void *context); void *context; unsigned frame_length; unsigned actual_length; int status; - /* for optional use by whatever driver currently owns the + /* For optional use by whatever driver currently owns the * spi_message ... between calls to spi_async and then later * complete(), that's the spi_controller controller driver. */ struct list_head queue; void *state; - /* list of spi_res reources when the spi message is processed */ + /* List of spi_res reources when the spi message is processed */ struct list_head resources; + + /* spi_prepare_message() was called for this message */ + bool prepared; }; static inline void spi_message_init_no_memset(struct spi_message *m) @@ -1127,7 +1154,7 @@ spi_max_transfer_size(struct spi_device *spi) if (ctlr->max_transfer_size) tr_max = ctlr->max_transfer_size(spi); - /* transfer size limit must not be greater than messsage size limit */ + /* Transfer size limit must not be greater than message size limit */ return min(tr_max, msg_max); } @@ -1278,7 +1305,7 @@ spi_read(struct spi_device *spi, void *buf, size_t len) return spi_sync_transfer(spi, &t, 1); } -/* this copies txbuf and rxbuf data; for small transfers only! */ +/* This copies txbuf and rxbuf data; for small transfers only! */ extern int spi_write_then_read(struct spi_device *spi, const void *txbuf, unsigned n_tx, void *rxbuf, unsigned n_rx); @@ -1301,7 +1328,7 @@ static inline ssize_t spi_w8r8(struct spi_device *spi, u8 cmd) status = spi_write_then_read(spi, &cmd, 1, &result, 1); - /* return negative errno or unsigned value */ + /* Return negative errno or unsigned value */ return (status < 0) ? status : result; } @@ -1326,7 +1353,7 @@ static inline ssize_t spi_w8r16(struct spi_device *spi, u8 cmd) status = spi_write_then_read(spi, &cmd, 1, &result, 2); - /* return negative errno or unsigned value */ + /* Return negative errno or unsigned value */ return (status < 0) ? status : result; } @@ -1406,7 +1433,7 @@ static inline ssize_t spi_w8r16be(struct spi_device *spi, u8 cmd) * are active in some dynamic board configuration models. */ struct spi_board_info { - /* the device name and module name are coupled, like platform_bus; + /* The device name and module name are coupled, like platform_bus; * "modalias" is normally the driver name. * * platform_data goes to spi_device.dev.platform_data, @@ -1419,7 +1446,7 @@ struct spi_board_info { void *controller_data; int irq; - /* slower signaling on noisy or low voltage boards */ + /* Slower signaling on noisy or low voltage boards */ u32 max_speed_hz; @@ -1448,7 +1475,7 @@ struct spi_board_info { extern int spi_register_board_info(struct spi_board_info const *info, unsigned n); #else -/* board init code may ignore whether SPI is configured or not */ +/* Board init code may ignore whether SPI is configured or not */ static inline int spi_register_board_info(struct spi_board_info const *info, unsigned n) { return 0; } |