diff options
Diffstat (limited to 'include/linux/dmaengine.h')
| -rw-r--r-- | include/linux/dmaengine.h | 200 |
1 files changed, 73 insertions, 127 deletions
diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h index adb0b084eb5..3e0f64c335c 100644 --- a/include/linux/dmaengine.h +++ b/include/linux/dmaengine.h @@ -29,32 +29,6 @@ #include <linux/dma-mapping.h> /** - * enum dma_state - resource PNP/power management state - * @DMA_RESOURCE_SUSPEND: DMA device going into low power state - * @DMA_RESOURCE_RESUME: DMA device returning to full power - * @DMA_RESOURCE_AVAILABLE: DMA device available to the system - * @DMA_RESOURCE_REMOVED: DMA device removed from the system - */ -enum dma_state { - DMA_RESOURCE_SUSPEND, - DMA_RESOURCE_RESUME, - DMA_RESOURCE_AVAILABLE, - DMA_RESOURCE_REMOVED, -}; - -/** - * enum dma_state_client - state of the channel in the client - * @DMA_ACK: client would like to use, or was using this channel - * @DMA_DUP: client has already seen this channel, or is not using this channel - * @DMA_NAK: client does not want to see any more channels - */ -enum dma_state_client { - DMA_ACK, - DMA_DUP, - DMA_NAK, -}; - -/** * typedef dma_cookie_t - an opaque DMA cookie * * if dma_cookie_t is >0 it's a DMA request cookie, <0 it's an error code @@ -89,23 +63,13 @@ enum dma_transaction_type { DMA_MEMSET, DMA_MEMCPY_CRC32C, DMA_INTERRUPT, + DMA_PRIVATE, DMA_SLAVE, }; /* last transaction type for creation of the capabilities mask */ #define DMA_TX_TYPE_END (DMA_SLAVE + 1) -/** - * enum dma_slave_width - DMA slave register access width. - * @DMA_SLAVE_WIDTH_8BIT: Do 8-bit slave register accesses - * @DMA_SLAVE_WIDTH_16BIT: Do 16-bit slave register accesses - * @DMA_SLAVE_WIDTH_32BIT: Do 32-bit slave register accesses - */ -enum dma_slave_width { - DMA_SLAVE_WIDTH_8BIT, - DMA_SLAVE_WIDTH_16BIT, - DMA_SLAVE_WIDTH_32BIT, -}; /** * enum dma_ctrl_flags - DMA flags to augment operation preparation, @@ -132,32 +96,6 @@ enum dma_ctrl_flags { typedef struct { DECLARE_BITMAP(bits, DMA_TX_TYPE_END); } dma_cap_mask_t; /** - * struct dma_slave - Information about a DMA slave - * @dev: device acting as DMA slave - * @dma_dev: required DMA master device. If non-NULL, the client can not be - * bound to other masters than this. - * @tx_reg: physical address of data register used for - * memory-to-peripheral transfers - * @rx_reg: physical address of data register used for - * peripheral-to-memory transfers - * @reg_width: peripheral register width - * - * If dma_dev is non-NULL, the client can not be bound to other DMA - * masters than the one corresponding to this device. The DMA master - * driver may use this to determine if there is controller-specific - * data wrapped around this struct. Drivers of platform code that sets - * the dma_dev field must therefore make sure to use an appropriate - * controller-specific dma slave structure wrapping this struct. - */ -struct dma_slave { - struct device *dev; - struct device *dma_dev; - dma_addr_t tx_reg; - dma_addr_t rx_reg; - enum dma_slave_width reg_width; -}; - -/** * struct dma_chan_percpu - the per-CPU part of struct dma_chan * @refcount: local_t used for open-coded "bigref" counting * @memcpy_count: transaction counter @@ -165,7 +103,6 @@ struct dma_slave { */ struct dma_chan_percpu { - local_t refcount; /* stats */ unsigned long memcpy_count; unsigned long bytes_transferred; @@ -176,13 +113,14 @@ struct dma_chan_percpu { * @device: ptr to the dma device who supplies this channel, always !%NULL * @cookie: last cookie value returned to client * @chan_id: channel ID for sysfs - * @class_dev: class device for sysfs + * @dev: class device for sysfs * @refcount: kref, used in "bigref" slow-mode * @slow_ref: indicates that the DMA channel is free * @rcu: the DMA channel's RCU head * @device_node: used to add this to the device chan list * @local: per-cpu pointer to a struct dma_chan_percpu * @client-count: how many clients are using this channel + * @table_count: number of appearances in the mem-to-mem allocation table */ struct dma_chan { struct dma_device *device; @@ -190,73 +128,47 @@ struct dma_chan { /* sysfs */ int chan_id; - struct device dev; - - struct kref refcount; - int slow_ref; - struct rcu_head rcu; + struct dma_chan_dev *dev; struct list_head device_node; struct dma_chan_percpu *local; int client_count; + int table_count; }; -#define to_dma_chan(p) container_of(p, struct dma_chan, dev) - -void dma_chan_cleanup(struct kref *kref); - -static inline void dma_chan_get(struct dma_chan *chan) -{ - if (unlikely(chan->slow_ref)) - kref_get(&chan->refcount); - else { - local_inc(&(per_cpu_ptr(chan->local, get_cpu())->refcount)); - put_cpu(); - } -} +/** + * struct dma_chan_dev - relate sysfs device node to backing channel device + * @chan - driver channel device + * @device - sysfs device + * @dev_id - parent dma_device dev_id + * @idr_ref - reference count to gate release of dma_device dev_id + */ +struct dma_chan_dev { + struct dma_chan *chan; + struct device device; + int dev_id; + atomic_t *idr_ref; +}; -static inline void dma_chan_put(struct dma_chan *chan) +static inline const char *dma_chan_name(struct dma_chan *chan) { - if (unlikely(chan->slow_ref)) - kref_put(&chan->refcount, dma_chan_cleanup); - else { - local_dec(&(per_cpu_ptr(chan->local, get_cpu())->refcount)); - put_cpu(); - } + return dev_name(&chan->dev->device); } -/* - * typedef dma_event_callback - function pointer to a DMA event callback - * For each channel added to the system this routine is called for each client. - * If the client would like to use the channel it returns '1' to signal (ack) - * the dmaengine core to take out a reference on the channel and its - * corresponding device. A client must not 'ack' an available channel more - * than once. When a channel is removed all clients are notified. If a client - * is using the channel it must 'ack' the removal. A client must not 'ack' a - * removed channel more than once. - * @client - 'this' pointer for the client context - * @chan - channel to be acted upon - * @state - available or removed - */ -struct dma_client; -typedef enum dma_state_client (*dma_event_callback) (struct dma_client *client, - struct dma_chan *chan, enum dma_state state); +void dma_chan_cleanup(struct kref *kref); /** - * struct dma_client - info on the entity making use of DMA services - * @event_callback: func ptr to call when something happens - * @cap_mask: only return channels that satisfy the requested capabilities - * a value of zero corresponds to any capability - * @slave: data for preparing slave transfer. Must be non-NULL iff the - * DMA_SLAVE capability is requested. - * @global_node: list_head for global dma_client_list + * typedef dma_filter_fn - callback filter for dma_request_channel + * @chan: channel to be reviewed + * @filter_param: opaque parameter passed through dma_request_channel + * + * When this optional parameter is specified in a call to dma_request_channel a + * suitable channel is passed to this routine for further dispositioning before + * being returned. Where 'suitable' indicates a non-busy channel that + * satisfies the given capability mask. It returns 'true' to indicate that the + * channel is suitable. */ -struct dma_client { - dma_event_callback event_callback; - dma_cap_mask_t cap_mask; - struct dma_slave *slave; - struct list_head global_node; -}; +typedef bool (*dma_filter_fn)(struct dma_chan *chan, void *filter_param); typedef void (*dma_async_tx_callback)(void *dma_async_param); /** @@ -323,14 +235,10 @@ struct dma_device { dma_cap_mask_t cap_mask; int max_xor; - struct kref refcount; - struct completion done; - int dev_id; struct device *dev; - int (*device_alloc_chan_resources)(struct dma_chan *chan, - struct dma_client *client); + int (*device_alloc_chan_resources)(struct dma_chan *chan); void (*device_free_chan_resources)(struct dma_chan *chan); struct dma_async_tx_descriptor *(*device_prep_dma_memcpy)( @@ -362,9 +270,18 @@ struct dma_device { /* --- public DMA engine API --- */ -void dma_async_client_register(struct dma_client *client); -void dma_async_client_unregister(struct dma_client *client); -void dma_async_client_chan_request(struct dma_client *client); +#ifdef CONFIG_DMA_ENGINE +void dmaengine_get(void); +void dmaengine_put(void); +#else +static inline void dmaengine_get(void) +{ +} +static inline void dmaengine_put(void) +{ +} +#endif + dma_cookie_t dma_async_memcpy_buf_to_buf(struct dma_chan *chan, void *dest, void *src, size_t len); dma_cookie_t dma_async_memcpy_buf_to_pg(struct dma_chan *chan, @@ -380,6 +297,11 @@ static inline void async_tx_ack(struct dma_async_tx_descriptor *tx) tx->flags |= DMA_CTRL_ACK; } +static inline void async_tx_clear_ack(struct dma_async_tx_descriptor *tx) +{ + tx->flags &= ~DMA_CTRL_ACK; +} + static inline bool async_tx_test_ack(struct dma_async_tx_descriptor *tx) { return (tx->flags & DMA_CTRL_ACK) == DMA_CTRL_ACK; @@ -406,6 +328,12 @@ __dma_cap_set(enum dma_transaction_type tx_type, dma_cap_mask_t *dstp) set_bit(tx_type, dstp->bits); } +#define dma_cap_zero(mask) __dma_cap_zero(&(mask)) +static inline void __dma_cap_zero(dma_cap_mask_t *dstp) +{ + bitmap_zero(dstp->bits, DMA_TX_TYPE_END); +} + #define dma_has_cap(tx, mask) __dma_has_cap((tx), &(mask)) static inline int __dma_has_cap(enum dma_transaction_type tx_type, dma_cap_mask_t *srcp) @@ -475,11 +403,29 @@ static inline enum dma_status dma_async_is_complete(dma_cookie_t cookie, } enum dma_status dma_sync_wait(struct dma_chan *chan, dma_cookie_t cookie); +#ifdef CONFIG_DMA_ENGINE +enum dma_status dma_wait_for_async_tx(struct dma_async_tx_descriptor *tx); +void dma_issue_pending_all(void); +#else +static inline enum dma_status dma_wait_for_async_tx(struct dma_async_tx_descriptor *tx) +{ + return DMA_SUCCESS; +} +static inline void dma_issue_pending_all(void) +{ + do { } while (0); +} +#endif /* --- DMA device --- */ int dma_async_device_register(struct dma_device *device); void dma_async_device_unregister(struct dma_device *device); +void dma_run_dependencies(struct dma_async_tx_descriptor *tx); +struct dma_chan *dma_find_channel(enum dma_transaction_type tx_type); +#define dma_request_channel(mask, x, y) __dma_request_channel(&(mask), x, y) +struct dma_chan *__dma_request_channel(dma_cap_mask_t *mask, dma_filter_fn fn, void *fn_param); +void dma_release_channel(struct dma_chan *chan); /* --- Helper iov-locking functions --- */ |