DMAENGINE: generic channel status v2

[net-next-2.6.git] / include / linux / dmaengine.h

diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h
index 78784982b33e36906dd47afd404287cdccdbc0f9..55b08e84ac8df5d08912bf61d10eb511f0bf9ec0 100644 (file)
--- a/include/linux/dmaengine.h
+++ b/include/linux/dmaengine.h
@@ -31,6 +31,8 @@
  * if dma_cookie_t is >0 it's a DMA request cookie, <0 it's an error code
  */
 typedef s32 dma_cookie_t;
+#define DMA_MIN_COOKIE 1
+#define DMA_MAX_COOKIE INT_MAX
 
 #define dma_submit_error(cookie) ((cookie) < 0 ? 1 : 0)
 
@@ -38,11 +40,13 @@ typedef s32 dma_cookie_t;
  * enum dma_status - DMA transaction status
  * @DMA_SUCCESS: transaction completed successfully
  * @DMA_IN_PROGRESS: transaction not yet processed
+ * @DMA_PAUSED: transaction is paused
  * @DMA_ERROR: transaction failed
  */
 enum dma_status {
        DMA_SUCCESS,
        DMA_IN_PROGRESS,
+       DMA_PAUSED,
        DMA_ERROR,
 };
 
@@ -104,6 +108,19 @@ enum dma_ctrl_flags {
        DMA_PREP_FENCE = (1 << 9),
 };
 
+/**
+ * enum dma_ctrl_cmd - DMA operations that can optionally be exercised
+ * on a running channel.
+ * @DMA_TERMINATE_ALL: terminate all ongoing transfers
+ * @DMA_PAUSE: pause ongoing transfers
+ * @DMA_RESUME: resume paused transfer
+ */
+enum dma_ctrl_cmd {
+       DMA_TERMINATE_ALL,
+       DMA_PAUSE,
+       DMA_RESUME,
+};
+
 /**
  * enum sum_check_bits - bit position of pq_check_flags
  */
@@ -162,7 +179,7 @@ struct dma_chan {
        struct dma_chan_dev *dev;
 
        struct list_head device_node;
-       struct dma_chan_percpu *local;
+       struct dma_chan_percpu __percpu *local;
        int client_count;
        int table_count;
        void *private;
@@ -233,6 +250,21 @@ struct dma_async_tx_descriptor {
        spinlock_t lock;
 };
 
+/**
+ * struct dma_tx_state - filled in to report the status of
+ * a transfer.
+ * @last: last completed DMA cookie
+ * @used: last issued DMA cookie (i.e. the one in progress)
+ * @residue: the remaining number of bytes left to transmit
+ *     on the selected transfer for states DMA_IN_PROGRESS and
+ *     DMA_PAUSED if this is implemented in the driver, else 0
+ */
+struct dma_tx_state {
+       dma_cookie_t last;
+       dma_cookie_t used;
+       u32 residue;
+};
+
 /**
  * struct dma_device - info on the entity supplying DMA services
  * @chancnt: how many DMA channels are supported
@@ -259,8 +291,12 @@ struct dma_async_tx_descriptor {
  * @device_prep_dma_memset: prepares a memset operation
  * @device_prep_dma_interrupt: prepares an end of chain interrupt operation
  * @device_prep_slave_sg: prepares a slave dma operation
- * @device_terminate_all: terminate all pending operations
- * @device_is_tx_complete: poll for transaction completion
+ * @device_control: manipulate all pending operations on a channel, returns
+ *     zero or error code
+ * @device_tx_status: poll for transaction completion, the optional
+ *     txstate parameter can be supplied with a pointer to get a
+ *     struct with auxilary transfer status information, otherwise the call
+ *     will just return a simple status code
  * @device_issue_pending: push pending transactions to hardware
  */
 struct dma_device {
@@ -311,11 +347,11 @@ struct dma_device {
                struct dma_chan *chan, struct scatterlist *sgl,
                unsigned int sg_len, enum dma_data_direction direction,
                unsigned long flags);
-       void (*device_terminate_all)(struct dma_chan *chan);
+       int (*device_control)(struct dma_chan *chan, enum dma_ctrl_cmd cmd);
 
-       enum dma_status (*device_is_tx_complete)(struct dma_chan *chan,
-                       dma_cookie_t cookie, dma_cookie_t *last,
-                       dma_cookie_t *used);
+       enum dma_status (*device_tx_status)(struct dma_chan *chan,
+                                           dma_cookie_t cookie,
+                                           struct dma_tx_state *txstate);
        void (*device_issue_pending)(struct dma_chan *chan);
 };
 
@@ -556,7 +592,15 @@ static inline void dma_async_issue_pending(struct dma_chan *chan)
 static inline enum dma_status dma_async_is_tx_complete(struct dma_chan *chan,
        dma_cookie_t cookie, dma_cookie_t *last, dma_cookie_t *used)
 {
-       return chan->device->device_is_tx_complete(chan, cookie, last, used);
+       struct dma_tx_state state;
+       enum dma_status status;
+
+       status = chan->device->device_tx_status(chan, cookie, &state);
+       if (last)
+               *last = state.last;
+       if (used)
+               *used = state.used;
+       return status;
 }
 
 #define dma_async_memcpy_complete(chan, cookie, last, used)\