From 636bdeaa1243327501edfd2a597ed7443eb4239a Mon Sep 17 00:00:00 2001 From: Dan Williams Date: Thu, 17 Apr 2008 20:17:26 -0700 Subject: 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 Signed-off-by: Dan Williams --- include/linux/dmaengine.h | 25 ++++++++++++++++++------- 1 file changed, 18 insertions(+), 7 deletions(-) (limited to 'include') 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)) -- cgit v1.2.3