diff options
author | Dan Williams <dan.j.williams@intel.com> | 2008-04-18 07:17:26 +0400 |
---|---|---|
committer | Dan Williams <dan.j.williams@intel.com> | 2008-04-18 00:25:54 +0400 |
commit | 636bdeaa1243327501edfd2a597ed7443eb4239a (patch) | |
tree | 59b894f124e3664ea4a537d7c07c527abdb9c8da /include/linux/dmaengine.h | |
parent | c4fe15541d0ef5cc8cc1ce43057663851f8fc387 (diff) | |
download | linux-636bdeaa1243327501edfd2a597ed7443eb4239a.tar.xz |
dmaengine: ack to flags: make use of the unused bits in the 'ack' field
'ack' is currently a simple integer that flags whether or not a client is done
touching fields in the given descriptor. It is effectively just a single bit
of information. Converting this to a flags parameter allows the other bits to
be put to use to control completion actions, like dma-unmap, and capture
results, like xor-zero-sum == 0.
Changes are one of:
1/ convert all open-coded ->ack manipulations to use async_tx_ack
and async_tx_test_ack.
2/ set the ack bit at prep time where possible
3/ make drivers store the flags at prep time
4/ add flags to the device_prep_dma_interrupt prototype
Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Diffstat (limited to 'include/linux/dmaengine.h')
-rw-r--r-- | include/linux/dmaengine.h | 25 |
1 files changed, 18 insertions, 7 deletions
diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h index cd34df78c6aa..b4d84ed6187d 100644 --- a/include/linux/dmaengine.h +++ b/include/linux/dmaengine.h @@ -95,12 +95,17 @@ enum dma_transaction_type { #define DMA_TX_TYPE_END (DMA_INTERRUPT + 1) /** - * enum dma_prep_flags - DMA flags to augment operation preparation + * enum dma_ctrl_flags - DMA flags to augment operation preparation, + * control completion, and communicate status. * @DMA_PREP_INTERRUPT - trigger an interrupt (callback) upon completion of * this transaction + * @DMA_CTRL_ACK - the descriptor cannot be reused until the client + * acknowledges receipt, i.e. has has a chance to establish any + * dependency chains */ -enum dma_prep_flags { +enum dma_ctrl_flags { DMA_PREP_INTERRUPT = (1 << 0), + DMA_CTRL_ACK = (1 << 1), }; /** @@ -211,8 +216,8 @@ typedef void (*dma_async_tx_callback)(void *dma_async_param); * ---dma generic offload fields--- * @cookie: tracking cookie for this transaction, set to -EBUSY if * this tx is sitting on a dependency list - * @ack: the descriptor can not be reused until the client acknowledges - * receipt, i.e. has has a chance to establish any dependency chains + * @flags: flags to augment operation preparation, control completion, and + * communicate status * @phys: physical address of the descriptor * @tx_list: driver common field for operations that require multiple * descriptors @@ -227,7 +232,7 @@ typedef void (*dma_async_tx_callback)(void *dma_async_param); */ struct dma_async_tx_descriptor { dma_cookie_t cookie; - int ack; + enum dma_ctrl_flags flags; /* not a 'long' to pack with cookie */ dma_addr_t phys; struct list_head tx_list; struct dma_chan *chan; @@ -290,7 +295,7 @@ struct dma_device { struct dma_chan *chan, dma_addr_t dest, int value, size_t len, unsigned long flags); struct dma_async_tx_descriptor *(*device_prep_dma_interrupt)( - struct dma_chan *chan); + struct dma_chan *chan, unsigned long flags); enum dma_status (*device_is_tx_complete)(struct dma_chan *chan, dma_cookie_t cookie, dma_cookie_t *last, @@ -316,7 +321,13 @@ void dma_async_tx_descriptor_init(struct dma_async_tx_descriptor *tx, static inline void async_tx_ack(struct dma_async_tx_descriptor *tx) { - tx->ack = 1; + tx->flags |= DMA_CTRL_ACK; +} + +static inline int +async_tx_test_ack(struct dma_async_tx_descriptor *tx) +{ + return tx->flags & DMA_CTRL_ACK; } #define first_dma_cap(mask) __first_dma_cap(&(mask)) |