12 files changed, 261 insertions, 172 deletions

diff --git a/crypto/async_tx/async_memcpy.c b/crypto/async_tx/async_memcpy.c
index 84caa4efc0d4..a5eda80e8427 100644
--- a/crypto/async_tx/async_memcpy.c
+++ b/crypto/async_tx/async_memcpy.c
@@ -77,7 +77,7 @@ async_memcpy(struct page *dest, struct page *src, unsigned int dest_offset,
                         /* if ack is already set then we cannot be sure
                          * we are referring to the correct operation
                          */
-                        BUG_ON(depend_tx->ack);
+                        BUG_ON(async_tx_test_ack(depend_tx));
                         if (dma_wait_for_async_tx(depend_tx) == DMA_ERROR)
                                 panic("%s: DMA_ERROR waiting for depend_tx\n",
                                         __func__);
diff --git a/crypto/async_tx/async_tx.c b/crypto/async_tx/async_tx.c
index 2be3bae89930..c6e772fc5ccd 100644
--- a/crypto/async_tx/async_tx.c
+++ b/crypto/async_tx/async_tx.c
@@ -89,13 +89,19 @@ dma_wait_for_async_tx(struct dma_async_tx_descriptor *tx)
                 iter = tx;
 
                 /* find the root of the unsubmitted dependency chain */
-                while (iter->cookie == -EBUSY) {
+                do {
                         parent = iter->parent;
-                        if (parent && parent->cookie == -EBUSY)
-                                iter = iter->parent;
-                        else
+                        if (!parent)
                                 break;
-                }
+                        else
+                                iter = parent;
+                } while (parent);
+
+                /* there is a small window for ->parent == NULL and
+                 * ->cookie == -EBUSY
+                 */
+                while (iter->cookie == -EBUSY)
+                        cpu_relax();
 
                 status = dma_sync_wait(iter->chan, iter->cookie);
         } while (status == DMA_IN_PROGRESS || (iter != tx));
@@ -111,24 +117,33 @@ EXPORT_SYMBOL_GPL(dma_wait_for_async_tx);
 void
 async_tx_run_dependencies(struct dma_async_tx_descriptor *tx)
 {
-        struct dma_async_tx_descriptor *dep_tx, *_dep_tx;
-        struct dma_device *dev;
+        struct dma_async_tx_descriptor *next = tx->next;
         struct dma_chan *chan;
 
-        list_for_each_entry_safe(dep_tx, _dep_tx, &tx->depend_list,
-                depend_node) {
-                chan = dep_tx->chan;
-                dev = chan->device;
-                /* we can't depend on ourselves */
-                BUG_ON(chan == tx->chan);
-                list_del(&dep_tx->depend_node);
-                tx->tx_submit(dep_tx);
-
-                /* we need to poke the engine as client code does not
-                 * know about dependency submission events
-                 */
-                dev->device_issue_pending(chan);
+        if (!next)
+                return;
+
+        tx->next = NULL;
+        chan = next->chan;
+
+        /* keep submitting up until a channel switch is detected
+         * in that case we will be called again as a result of
+         * processing the interrupt from async_tx_channel_switch
+         */
+        while (next && next->chan == chan) {
+                struct dma_async_tx_descriptor *_next;
+
+                spin_lock_bh(&next->lock);
+                next->parent = NULL;
+                _next = next->next;
+                next->next = NULL;
+                spin_unlock_bh(&next->lock);
+
+                next->tx_submit(next);
+                next = _next;
         }
+
+        chan->device->device_issue_pending(chan);
 }
 EXPORT_SYMBOL_GPL(async_tx_run_dependencies);
 
@@ -397,6 +412,92 @@ static void __exit async_tx_exit(void)
 }
 #endif
 
+
+/**
+ * async_tx_channel_switch - queue an interrupt descriptor with a dependency
+ *      pre-attached.
+ * @depend_tx: the operation that must finish before the new operation runs
+ * @tx: the new operation
+ */
+static void
+async_tx_channel_switch(struct dma_async_tx_descriptor *depend_tx,
+                        struct dma_async_tx_descriptor *tx)
+{
+        struct dma_chan *chan;
+        struct dma_device *device;
+        struct dma_async_tx_descriptor *intr_tx = (void *) ~0;
+
+        /* first check to see if we can still append to depend_tx */
+        spin_lock_bh(&depend_tx->lock);
+        if (depend_tx->parent && depend_tx->chan == tx->chan) {
+                tx->parent = depend_tx;
+                depend_tx->next = tx;
+                intr_tx = NULL;
+        }
+        spin_unlock_bh(&depend_tx->lock);
+
+        if (!intr_tx)
+                return;
+
+        chan = depend_tx->chan;
+        device = chan->device;
+
+        /* see if we can schedule an interrupt
+         * otherwise poll for completion
+         */
+        if (dma_has_cap(DMA_INTERRUPT, device->cap_mask))
+                intr_tx = device->device_prep_dma_interrupt(chan, 0);
+        else
+                intr_tx = NULL;
+
+        if (intr_tx) {
+                intr_tx->callback = NULL;
+                intr_tx->callback_param = NULL;
+                tx->parent = intr_tx;
+                /* safe to set ->next outside the lock since we know we are
+                 * not submitted yet
+                 */
+                intr_tx->next = tx;
+
+                /* check if we need to append */
+                spin_lock_bh(&depend_tx->lock);
+                if (depend_tx->parent) {
+                        intr_tx->parent = depend_tx;
+                        depend_tx->next = intr_tx;
+                        async_tx_ack(intr_tx);
+                        intr_tx = NULL;
+                }
+                spin_unlock_bh(&depend_tx->lock);
+
+                if (intr_tx) {
+                        intr_tx->parent = NULL;
+                        intr_tx->tx_submit(intr_tx);
+                        async_tx_ack(intr_tx);
+                }
+        } else {
+                if (dma_wait_for_async_tx(depend_tx) == DMA_ERROR)
+                        panic("%s: DMA_ERROR waiting for depend_tx\n",
+                              __func__);
+                tx->tx_submit(tx);
+        }
+}
+
+
+/**
+ * submit_disposition - while holding depend_tx->lock we must avoid submitting
+ *      new operations to prevent a circular locking dependency with
+ *      drivers that already hold a channel lock when calling
+ *      async_tx_run_dependencies.
+ * @ASYNC_TX_SUBMITTED: we were able to append the new operation under the lock
+ * @ASYNC_TX_CHANNEL_SWITCH: when the lock is dropped schedule a channel switch
+ * @ASYNC_TX_DIRECT_SUBMIT: when the lock is dropped submit directly
+ */
+enum submit_disposition {
+        ASYNC_TX_SUBMITTED,
+        ASYNC_TX_CHANNEL_SWITCH,
+        ASYNC_TX_DIRECT_SUBMIT,
+};
+
 void
 async_tx_submit(struct dma_chan *chan, struct dma_async_tx_descriptor *tx,
         enum async_tx_flags flags, struct dma_async_tx_descriptor *depend_tx,
@@ -405,28 +506,55 @@ async_tx_submit(struct dma_chan *chan, struct dma_async_tx_descriptor *tx,
         tx->callback = cb_fn;
         tx->callback_param = cb_param;
 
-        /* set this new tx to run after depend_tx if:
-         * 1/ a dependency exists (depend_tx is !NULL)
-         * 2/ the tx can not be submitted to the current channel
-         */
-        if (depend_tx && depend_tx->chan != chan) {
-                /* if ack is already set then we cannot be sure
+        if (depend_tx) {
+                enum submit_disposition s;
+
+                /* sanity check the dependency chain:
+                 * 1/ if ack is already set then we cannot be sure
                  * we are referring to the correct operation
+                 * 2/ dependencies are 1:1 i.e. two transactions can
+                 * not depend on the same parent
                  */
-                BUG_ON(depend_tx->ack);
+                BUG_ON(async_tx_test_ack(depend_tx) || depend_tx->next ||
+                       tx->parent);
 
-                tx->parent = depend_tx;
+                /* the lock prevents async_tx_run_dependencies from missing
+                 * the setting of ->next when ->parent != NULL
+                 */
                 spin_lock_bh(&depend_tx->lock);
-                list_add_tail(&tx->depend_node, &depend_tx->depend_list);
-                if (depend_tx->cookie == 0) {
-                        struct dma_chan *dep_chan = depend_tx->chan;
-                        struct dma_device *dep_dev = dep_chan->device;
-                        dep_dev->device_dependency_added(dep_chan);
+                if (depend_tx->parent) {
+                        /* we have a parent so we can not submit directly
+                         * if we are staying on the same channel: append
+                         * else: channel switch
+                         */
+                        if (depend_tx->chan == chan) {
+                                tx->parent = depend_tx;
+                                depend_tx->next = tx;
+                                s = ASYNC_TX_SUBMITTED;
+                        } else
+                                s = ASYNC_TX_CHANNEL_SWITCH;
+                } else {
+                        /* we do not have a parent so we may be able to submit
+                         * directly if we are staying on the same channel
+                         */
+                        if (depend_tx->chan == chan)
+                                s = ASYNC_TX_DIRECT_SUBMIT;
+                        else
+                                s = ASYNC_TX_CHANNEL_SWITCH;
                 }
                 spin_unlock_bh(&depend_tx->lock);
 
-                /* schedule an interrupt to trigger the channel switch */
-                async_trigger_callback(ASYNC_TX_ACK, depend_tx, NULL, NULL);
+                switch (s) {
+                case ASYNC_TX_SUBMITTED:
+                        break;
+                case ASYNC_TX_CHANNEL_SWITCH:
+                        async_tx_channel_switch(depend_tx, tx);
+                        break;
+                case ASYNC_TX_DIRECT_SUBMIT:
+                        tx->parent = NULL;
+                        tx->tx_submit(tx);
+                        break;
+                }
         } else {
                 tx->parent = NULL;
                 tx->tx_submit(tx);
@@ -467,7 +595,7 @@ async_trigger_callback(enum async_tx_flags flags,
                 if (device && !dma_has_cap(DMA_INTERRUPT, device->cap_mask))
                         device = NULL;
 
-                tx = device ? device->device_prep_dma_interrupt(chan) : NULL;
+                tx = device ? device->device_prep_dma_interrupt(chan, 0) : NULL;
         } else
                 tx = NULL;
 
@@ -483,7 +611,7 @@ async_trigger_callback(enum async_tx_flags flags,
                         /* if ack is already set then we cannot be sure
                          * we are referring to the correct operation
                          */
-                        BUG_ON(depend_tx->ack);
+                        BUG_ON(async_tx_test_ack(depend_tx));
                         if (dma_wait_for_async_tx(depend_tx) == DMA_ERROR)
                                 panic("%s: DMA_ERROR waiting for depend_tx\n",
                                         __func__);
diff --git a/crypto/async_tx/async_xor.c b/crypto/async_tx/async_xor.c
index 1c445c7bdab7..3a0dddca5a10 100644
--- a/crypto/async_tx/async_xor.c
+++ b/crypto/async_tx/async_xor.c
@@ -191,7 +191,7 @@ async_xor(struct page *dest, struct page **src_list, unsigned int offset,
                                 /* if ack is already set then we cannot be sure
                                  * we are referring to the correct operation
                                  */
-                                BUG_ON(depend_tx->ack);
+                                BUG_ON(async_tx_test_ack(depend_tx));
                                 if (dma_wait_for_async_tx(depend_tx) ==
                                         DMA_ERROR)
                                         panic("%s: DMA_ERROR waiting for "
diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig
index 27340a7b19dd..6239c3df30ac 100644
--- a/drivers/dma/Kconfig
+++ b/drivers/dma/Kconfig
@@ -46,14 +46,6 @@ config FSL_DMA
           MPC8560/40, MPC8555, MPC8548 and MPC8641 processors.
           The MPC8349, MPC8360 is also supported.
 
-config FSL_DMA_SELFTEST
-        bool "Enable the self test for each DMA channel"
-        depends on FSL_DMA
-        default y
-        ---help---
-          Enable the self test for each DMA channel. A self test will be
-          performed after the channel probed to ensure the DMA works well.
-
 config DMA_ENGINE
         bool
 
diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c
index 8db0e7f9d3f4..d6dc70fd7527 100644
--- a/drivers/dma/dmaengine.c
+++ b/drivers/dma/dmaengine.c
@@ -362,7 +362,6 @@ int dma_async_device_register(struct dma_device *device)
 
         BUG_ON(!device->device_alloc_chan_resources);
         BUG_ON(!device->device_free_chan_resources);
-        BUG_ON(!device->device_dependency_added);
         BUG_ON(!device->device_is_tx_complete);
         BUG_ON(!device->device_issue_pending);
         BUG_ON(!device->dev);
@@ -479,7 +478,8 @@ dma_async_memcpy_buf_to_buf(struct dma_chan *chan, void *dest,
 
         dma_src = dma_map_single(dev->dev, src, len, DMA_TO_DEVICE);
         dma_dest = dma_map_single(dev->dev, dest, len, DMA_FROM_DEVICE);
-        tx = dev->device_prep_dma_memcpy(chan, dma_dest, dma_src, len, 0);
+        tx = dev->device_prep_dma_memcpy(chan, dma_dest, dma_src, len,
+                                         DMA_CTRL_ACK);
 
         if (!tx) {
                 dma_unmap_single(dev->dev, dma_src, len, DMA_TO_DEVICE);
@@ -487,7 +487,6 @@ dma_async_memcpy_buf_to_buf(struct dma_chan *chan, void *dest,
                 return -ENOMEM;
         }
 
-        tx->ack = 1;
         tx->callback = NULL;
         cookie = tx->tx_submit(tx);
 
@@ -525,7 +524,8 @@ dma_async_memcpy_buf_to_pg(struct dma_chan *chan, struct page *page,
 
         dma_src = dma_map_single(dev->dev, kdata, len, DMA_TO_DEVICE);
         dma_dest = dma_map_page(dev->dev, page, offset, len, DMA_FROM_DEVICE);
-        tx = dev->device_prep_dma_memcpy(chan, dma_dest, dma_src, len, 0);
+        tx = dev->device_prep_dma_memcpy(chan, dma_dest, dma_src, len,
+                                         DMA_CTRL_ACK);
 
         if (!tx) {
                 dma_unmap_single(dev->dev, dma_src, len, DMA_TO_DEVICE);
@@ -533,7 +533,6 @@ dma_async_memcpy_buf_to_pg(struct dma_chan *chan, struct page *page,
                 return -ENOMEM;
         }
 
-        tx->ack = 1;
         tx->callback = NULL;
         cookie = tx->tx_submit(tx);
 
@@ -574,7 +573,8 @@ dma_async_memcpy_pg_to_pg(struct dma_chan *chan, struct page *dest_pg,
         dma_src = dma_map_page(dev->dev, src_pg, src_off, len, DMA_TO_DEVICE);
         dma_dest = dma_map_page(dev->dev, dest_pg, dest_off, len,
                                 DMA_FROM_DEVICE);
-        tx = dev->device_prep_dma_memcpy(chan, dma_dest, dma_src, len, 0);
+        tx = dev->device_prep_dma_memcpy(chan, dma_dest, dma_src, len,
+                                         DMA_CTRL_ACK);
 
         if (!tx) {
                 dma_unmap_page(dev->dev, dma_src, len, DMA_TO_DEVICE);
@@ -582,7 +582,6 @@ dma_async_memcpy_pg_to_pg(struct dma_chan *chan, struct page *dest_pg,
                 return -ENOMEM;
         }
 
-        tx->ack = 1;
         tx->callback = NULL;
         cookie = tx->tx_submit(tx);
 
@@ -600,8 +599,6 @@ void dma_async_tx_descriptor_init(struct dma_async_tx_descriptor *tx,
 {
         tx->chan = chan;
         spin_lock_init(&tx->lock);
-        INIT_LIST_HEAD(&tx->depend_node);
-        INIT_LIST_HEAD(&tx->depend_list);
 }
 EXPORT_SYMBOL(dma_async_tx_descriptor_init);
 
diff --git a/drivers/dma/fsldma.c b/drivers/dma/fsldma.c
index df163687c91a..054eabffc185 100644
--- a/drivers/dma/fsldma.c
+++ b/drivers/dma/fsldma.c
@@ -412,7 +412,7 @@ static void fsl_dma_free_chan_resources(struct dma_chan *chan)
 }
 
 static struct dma_async_tx_descriptor *
-fsl_dma_prep_interrupt(struct dma_chan *chan)
+fsl_dma_prep_interrupt(struct dma_chan *chan, unsigned long flags)
 {
         struct fsl_dma_chan *fsl_chan;
         struct fsl_desc_sw *new;
@@ -429,7 +429,7 @@ fsl_dma_prep_interrupt(struct dma_chan *chan)
         }
 
         new->async_tx.cookie = -EBUSY;
-        new->async_tx.ack = 0;
+        new->async_tx.flags = flags;
 
         /* Insert the link descriptor to the LD ring */
         list_add_tail(&new->node, &new->async_tx.tx_list);
@@ -482,7 +482,7 @@ static struct dma_async_tx_descriptor *fsl_dma_prep_memcpy(
                         set_desc_next(fsl_chan, &prev->hw, new->async_tx.phys);
 
                 new->async_tx.cookie = 0;
-                new->async_tx.ack = 1;
+                async_tx_ack(&new->async_tx);
 
                 prev = new;
                 len -= copy;
@@ -493,7 +493,7 @@ static struct dma_async_tx_descriptor *fsl_dma_prep_memcpy(
                 list_add_tail(&new->node, &first->async_tx.tx_list);
         } while (len);
 
-        new->async_tx.ack = 0; /* client is in control of this ack */
+        new->async_tx.flags = flags; /* client is in control of this ack */
         new->async_tx.cookie = -EBUSY;
 
         /* Set End-of-link to the last link descriptor of new list*/
@@ -658,13 +658,6 @@ static void fsl_dma_memcpy_issue_pending(struct dma_chan *chan)
         fsl_chan_xfer_ld_queue(fsl_chan);
 }
 
-static void fsl_dma_dependency_added(struct dma_chan *chan)
-{
-        struct fsl_dma_chan *fsl_chan = to_fsl_chan(chan);
-
-        fsl_chan_ld_cleanup(fsl_chan);
-}
-
 /**
  * fsl_dma_is_complete - Determine the DMA status
  * @fsl_chan : Freescale DMA channel
@@ -696,6 +689,8 @@ static irqreturn_t fsl_dma_chan_do_interrupt(int irq, void *data)
 {
         struct fsl_dma_chan *fsl_chan = (struct fsl_dma_chan *)data;
         u32 stat;
+        int update_cookie = 0;
+        int xfer_ld_q = 0;
 
         stat = get_sr(fsl_chan);
         dev_dbg(fsl_chan->dev, "event: channel %d, stat = 0x%x\n",
@@ -720,8 +715,8 @@ static irqreturn_t fsl_dma_chan_do_interrupt(int irq, void *data)
                          * Now, update the completed cookie, and continue the
                          * next uncompleted transfer.
                          */
-                        fsl_dma_update_completed_cookie(fsl_chan);
-                        fsl_chan_xfer_ld_queue(fsl_chan);
+                        update_cookie = 1;
+                        xfer_ld_q = 1;
                 }
                 stat &= ~FSL_DMA_SR_PE;
         }
@@ -734,19 +729,33 @@ static irqreturn_t fsl_dma_chan_do_interrupt(int irq, void *data)
                 dev_dbg(fsl_chan->dev, "event: clndar %p, nlndar %p\n",
                         (void *)get_cdar(fsl_chan), (void *)get_ndar(fsl_chan));
                 stat &= ~FSL_DMA_SR_EOSI;
-                fsl_dma_update_completed_cookie(fsl_chan);
+                update_cookie = 1;
+        }
+
+        /* For MPC8349, EOCDI event need to update cookie
+         * and start the next transfer if it exist.
+         */
+        if (stat & FSL_DMA_SR_EOCDI) {
+                dev_dbg(fsl_chan->dev, "event: End-of-Chain link INT\n");
+                stat &= ~FSL_DMA_SR_EOCDI;
+                update_cookie = 1;
+                xfer_ld_q = 1;
         }
 
         /* If it current transfer is the end-of-transfer,
          * we should clear the Channel Start bit for
          * prepare next transfer.
          */
-        if (stat & (FSL_DMA_SR_EOLNI | FSL_DMA_SR_EOCDI)) {
+        if (stat & FSL_DMA_SR_EOLNI) {
                 dev_dbg(fsl_chan->dev, "event: End-of-link INT\n");
                 stat &= ~FSL_DMA_SR_EOLNI;
-                fsl_chan_xfer_ld_queue(fsl_chan);
+                xfer_ld_q = 1;
         }
 
+        if (update_cookie)
+                fsl_dma_update_completed_cookie(fsl_chan);
+        if (xfer_ld_q)
+                fsl_chan_xfer_ld_queue(fsl_chan);
         if (stat)
                 dev_dbg(fsl_chan->dev, "event: unhandled sr 0x%02x\n",
                                         stat);
@@ -776,15 +785,13 @@ static void dma_do_tasklet(unsigned long data)
         fsl_chan_ld_cleanup(fsl_chan);
 }
 
-#ifdef FSL_DMA_CALLBACKTEST
-static void fsl_dma_callback_test(struct fsl_dma_chan *fsl_chan)
+static void fsl_dma_callback_test(void *param)
 {
+        struct fsl_dma_chan *fsl_chan = param;
         if (fsl_chan)
-                dev_info(fsl_chan->dev, "selftest: callback is ok!\n");
+                dev_dbg(fsl_chan->dev, "selftest: callback is ok!\n");
 }
-#endif
 
-#ifdef CONFIG_FSL_DMA_SELFTEST
 static int fsl_dma_self_test(struct fsl_dma_chan *fsl_chan)
 {
         struct dma_chan *chan;
@@ -867,7 +874,7 @@ static int fsl_dma_self_test(struct fsl_dma_chan *fsl_chan)
         async_tx_ack(tx3);
 
         /* Interrupt tx test */
-        tx1 = fsl_dma_prep_interrupt(chan);
+        tx1 = fsl_dma_prep_interrupt(chan, 0);
         async_tx_ack(tx1);
         cookie = fsl_dma_tx_submit(tx1);
 
@@ -875,13 +882,11 @@ static int fsl_dma_self_test(struct fsl_dma_chan *fsl_chan)
         cookie = fsl_dma_tx_submit(tx3);
         cookie = fsl_dma_tx_submit(tx2);
 
-#ifdef FSL_DMA_CALLBACKTEST
         if (dma_has_cap(DMA_INTERRUPT, ((struct fsl_dma_device *)
             dev_get_drvdata(fsl_chan->dev->parent))->common.cap_mask)) {
                 tx3->callback = fsl_dma_callback_test;
                 tx3->callback_param = fsl_chan;
         }
-#endif
         fsl_dma_memcpy_issue_pending(chan);
         msleep(2);
 
@@ -906,7 +911,6 @@ out:
         kfree(src);
         return err;
 }
-#endif
 
 static int __devinit of_fsl_dma_chan_probe(struct of_device *dev,
                         const struct of_device_id *match)
@@ -997,11 +1001,9 @@ static int __devinit of_fsl_dma_chan_probe(struct of_device *dev,
                 }
         }
 
-#ifdef CONFIG_FSL_DMA_SELFTEST
         err = fsl_dma_self_test(new_fsl_chan);
         if (err)
                 goto err;
-#endif
 
         dev_info(&dev->dev, "#%d (%s), irq %d\n", new_fsl_chan->id,
                                 match->compatible, new_fsl_chan->irq);
@@ -1080,7 +1082,6 @@ static int __devinit of_fsl_dma_probe(struct of_device *dev,
         fdev->common.device_prep_dma_memcpy = fsl_dma_prep_memcpy;
         fdev->common.device_is_tx_complete = fsl_dma_is_complete;
         fdev->common.device_issue_pending = fsl_dma_memcpy_issue_pending;
-        fdev->common.device_dependency_added = fsl_dma_dependency_added;
         fdev->common.dev = &dev->dev;
 
         irq = irq_of_parse_and_map(dev->node, 0);
diff --git a/drivers/dma/ioat_dma.c b/drivers/dma/ioat_dma.c
index 4017d9e7acd2..318e8a22d814 100644
--- a/drivers/dma/ioat_dma.c
+++ b/drivers/dma/ioat_dma.c
@@ -212,14 +212,14 @@ static dma_cookie_t ioat1_tx_submit(struct dma_async_tx_descriptor *tx)
         u32 copy;
         size_t len;
         dma_addr_t src, dst;
-        int orig_ack;
+        unsigned long orig_flags;
         unsigned int desc_count = 0;
 
         /* src and dest and len are stored in the initial descriptor */
         len = first->len;
         src = first->src;
         dst = first->dst;
-        orig_ack = first->async_tx.ack;
+        orig_flags = first->async_tx.flags;
         new = first;
 
         spin_lock_bh(&ioat_chan->desc_lock);
@@ -228,7 +228,7 @@ static dma_cookie_t ioat1_tx_submit(struct dma_async_tx_descriptor *tx)
         do {
                 copy = min_t(size_t, len, ioat_chan->xfercap);
 
-                new->async_tx.ack = 1;
+                async_tx_ack(&new->async_tx);
 
                 hw = new->hw;
                 hw->size = copy;
@@ -264,7 +264,7 @@ static dma_cookie_t ioat1_tx_submit(struct dma_async_tx_descriptor *tx)
         }
 
         new->tx_cnt = desc_count;
-        new->async_tx.ack = orig_ack; /* client is in control of this ack */
+        new->async_tx.flags = orig_flags; /* client is in control of this ack */
 
         /* store the original values for use in later cleanup */
         if (new != first) {
@@ -304,14 +304,14 @@ static dma_cookie_t ioat2_tx_submit(struct dma_async_tx_descriptor *tx)
         u32 copy;
         size_t len;
         dma_addr_t src, dst;
-        int orig_ack;
+        unsigned long orig_flags;
         unsigned int desc_count = 0;
 
         /* src and dest and len are stored in the initial descriptor */
         len = first->len;
         src = first->src;
         dst = first->dst;
-        orig_ack = first->async_tx.ack;
+        orig_flags = first->async_tx.flags;
         new = first;
 
         /*
@@ -321,7 +321,7 @@ static dma_cookie_t ioat2_tx_submit(struct dma_async_tx_descriptor *tx)
         do {
                 copy = min_t(size_t, len, ioat_chan->xfercap);
 
-                new->async_tx.ack = 1;
+                async_tx_ack(&new->async_tx);
 
                 hw = new->hw;
                 hw->size = copy;
@@ -349,7 +349,7 @@ static dma_cookie_t ioat2_tx_submit(struct dma_async_tx_descriptor *tx)
         }
 
         new->tx_cnt = desc_count;
-        new->async_tx.ack = orig_ack; /* client is in control of this ack */
+        new->async_tx.flags = orig_flags; /* client is in control of this ack */
 
         /* store the original values for use in later cleanup */
         if (new != first) {
@@ -714,7 +714,7 @@ static struct dma_async_tx_descriptor *ioat1_dma_prep_memcpy(
                 new->len = len;
                 new->dst = dma_dest;
                 new->src = dma_src;
-                new->async_tx.ack = 0;
+                new->async_tx.flags = flags;
                 return &new->async_tx;
         } else
                 return NULL;
@@ -742,7 +742,7 @@ static struct dma_async_tx_descriptor *ioat2_dma_prep_memcpy(
                 new->len = len;
                 new->dst = dma_dest;
                 new->src = dma_src;
-                new->async_tx.ack = 0;
+                new->async_tx.flags = flags;
                 return &new->async_tx;
         } else
                 return NULL;
@@ -842,7 +842,7 @@ static void ioat_dma_memcpy_cleanup(struct ioat_dma_chan *ioat_chan)
                                  * a completed entry, but not the last, so clean
                                  * up if the client is done with the descriptor
                                  */
-                                if (desc->async_tx.ack) {
+                                if (async_tx_test_ack(&desc->async_tx)) {
                                         list_del(&desc->node);
                                         list_add_tail(&desc->node,
                                                       &ioat_chan->free_desc);
@@ -924,17 +924,6 @@ static void ioat_dma_memcpy_cleanup(struct ioat_dma_chan *ioat_chan)
         spin_unlock_bh(&ioat_chan->cleanup_lock);
 }
 
-static void ioat_dma_dependency_added(struct dma_chan *chan)
-{
-        struct ioat_dma_chan *ioat_chan = to_ioat_chan(chan);
-        spin_lock_bh(&ioat_chan->desc_lock);
-        if (ioat_chan->pending == 0) {
-                spin_unlock_bh(&ioat_chan->desc_lock);
-                ioat_dma_memcpy_cleanup(ioat_chan);
-        } else
-                spin_unlock_bh(&ioat_chan->desc_lock);
-}
-
 /**
  * ioat_dma_is_complete - poll the status of a IOAT DMA transaction
  * @chan: IOAT DMA channel handle
@@ -990,7 +979,7 @@ static void ioat_dma_start_null_desc(struct ioat_dma_chan *ioat_chan)
         desc->hw->size = 0;
         desc->hw->src_addr = 0;
         desc->hw->dst_addr = 0;
-        desc->async_tx.ack = 1;
+        async_tx_ack(&desc->async_tx);
         switch (ioat_chan->device->version) {
         case IOAT_VER_1_2:
                 desc->hw->next = 0;
@@ -1316,7 +1305,6 @@ struct ioatdma_device *ioat_dma_probe(struct pci_dev *pdev,
 
         dma_cap_set(DMA_MEMCPY, device->common.cap_mask);
         device->common.device_is_tx_complete = ioat_dma_is_complete;
-        device->common.device_dependency_added = ioat_dma_dependency_added;
         switch (device->version) {
         case IOAT_VER_1_2:
                 device->common.device_prep_dma_memcpy = ioat1_dma_prep_memcpy;
diff --git a/drivers/dma/iop-adma.c b/drivers/dma/iop-adma.c
index f82b0906d466..762b729672e0 100644
--- a/drivers/dma/iop-adma.c
+++ b/drivers/dma/iop-adma.c
@@ -63,7 +63,6 @@ iop_adma_run_tx_complete_actions(struct iop_adma_desc_slot *desc,
         struct iop_adma_chan *iop_chan, dma_cookie_t cookie)
 {
         BUG_ON(desc->async_tx.cookie < 0);
-        spin_lock_bh(&desc->async_tx.lock);
         if (desc->async_tx.cookie > 0) {
                 cookie = desc->async_tx.cookie;
                 desc->async_tx.cookie = 0;
@@ -101,7 +100,6 @@ iop_adma_run_tx_complete_actions(struct iop_adma_desc_slot *desc,
 
         /* run dependent operations */
         async_tx_run_dependencies(&desc->async_tx);
-        spin_unlock_bh(&desc->async_tx.lock);
 
         return cookie;
 }
@@ -113,7 +111,7 @@ iop_adma_clean_slot(struct iop_adma_desc_slot *desc,
         /* the client is allowed to attach dependent operations
          * until 'ack' is set
          */
-        if (!desc->async_tx.ack)
+        if (!async_tx_test_ack(&desc->async_tx))
                 return 0;
 
         /* leave the last descriptor in the chain
@@ -150,7 +148,7 @@ static void __iop_adma_slot_cleanup(struct iop_adma_chan *iop_chan)
                         "this_desc: %#x next_desc: %#x ack: %d\n",
                         iter->async_tx.cookie, iter->idx, busy,
                         iter->async_tx.phys, iop_desc_get_next_desc(iter),
-                        iter->async_tx.ack);
+                        async_tx_test_ack(&iter->async_tx));
                 prefetch(_iter);
                 prefetch(&_iter->async_tx);
 
@@ -257,8 +255,6 @@ static void __iop_adma_slot_cleanup(struct iop_adma_chan *iop_chan)
 
         BUG_ON(!seen_current);
 
-        iop_chan_idle(busy, iop_chan);
-
         if (cookie > 0) {
                 iop_chan->completed_cookie = cookie;
                 pr_debug("\tcompleted cookie %d\n", cookie);
@@ -275,8 +271,11 @@ iop_adma_slot_cleanup(struct iop_adma_chan *iop_chan)
 
 static void iop_adma_tasklet(unsigned long data)
 {
-        struct iop_adma_chan *chan = (struct iop_adma_chan *) data;
-        __iop_adma_slot_cleanup(chan);
+        struct iop_adma_chan *iop_chan = (struct iop_adma_chan *) data;
+
+        spin_lock(&iop_chan->lock);
+        __iop_adma_slot_cleanup(iop_chan);
+        spin_unlock(&iop_chan->lock);
 }
 
 static struct iop_adma_desc_slot *
@@ -339,9 +338,7 @@ retry:
 
                                 /* pre-ack all but the last descriptor */
                                 if (num_slots != slots_per_op)
-                                        iter->async_tx.ack = 1;
-                                else
-                                        iter->async_tx.ack = 0;
+                                        async_tx_ack(&iter->async_tx);
 
                                 list_add_tail(&iter->chain_node, &chain);
                                 alloc_tail = iter;
@@ -514,7 +511,7 @@ static int iop_adma_alloc_chan_resources(struct dma_chan *chan)
 }
 
 static struct dma_async_tx_descriptor *
-iop_adma_prep_dma_interrupt(struct dma_chan *chan)
+iop_adma_prep_dma_interrupt(struct dma_chan *chan, unsigned long flags)
 {
         struct iop_adma_chan *iop_chan = to_iop_adma_chan(chan);
         struct iop_adma_desc_slot *sw_desc, *grp_start;
@@ -529,6 +526,7 @@ iop_adma_prep_dma_interrupt(struct dma_chan *chan)
                 grp_start = sw_desc->group_head;
                 iop_desc_init_interrupt(grp_start, iop_chan);
                 grp_start->unmap_len = 0;
+                sw_desc->async_tx.flags = flags;
         }
         spin_unlock_bh(&iop_chan->lock);
 
@@ -561,6 +559,7 @@ iop_adma_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dma_dest,
                 iop_desc_set_memcpy_src_addr(grp_start, dma_src);
                 sw_desc->unmap_src_cnt = 1;
                 sw_desc->unmap_len = len;
+                sw_desc->async_tx.flags = flags;
         }
         spin_unlock_bh(&iop_chan->lock);
 
@@ -593,6 +592,7 @@ iop_adma_prep_dma_memset(struct dma_chan *chan, dma_addr_t dma_dest,
                 iop_desc_set_dest_addr(grp_start, iop_chan, dma_dest);
                 sw_desc->unmap_src_cnt = 1;
                 sw_desc->unmap_len = len;
+                sw_desc->async_tx.flags = flags;
         }
         spin_unlock_bh(&iop_chan->lock);
 
@@ -626,6 +626,7 @@ iop_adma_prep_dma_xor(struct dma_chan *chan, dma_addr_t dma_dest,
                 iop_desc_set_dest_addr(grp_start, iop_chan, dma_dest);
                 sw_desc->unmap_src_cnt = src_cnt;
                 sw_desc->unmap_len = len;
+                sw_desc->async_tx.flags = flags;
                 while (src_cnt--)
                         iop_desc_set_xor_src_addr(grp_start, src_cnt,
                                                   dma_src[src_cnt]);
@@ -662,6 +663,7 @@ iop_adma_prep_dma_zero_sum(struct dma_chan *chan, dma_addr_t *dma_src,
                         __func__, grp_start->xor_check_result);
                 sw_desc->unmap_src_cnt = src_cnt;
                 sw_desc->unmap_len = len;
+                sw_desc->async_tx.flags = flags;
                 while (src_cnt--)
                         iop_desc_set_zero_sum_src_addr(grp_start, src_cnt,
                                                        dma_src[src_cnt]);
@@ -671,12 +673,6 @@ iop_adma_prep_dma_zero_sum(struct dma_chan *chan, dma_addr_t *dma_src,
         return sw_desc ? &sw_desc->async_tx : NULL;
 }
 
-static void iop_adma_dependency_added(struct dma_chan *chan)
-{
-        struct iop_adma_chan *iop_chan = to_iop_adma_chan(chan);
-        tasklet_schedule(&iop_chan->irq_tasklet);
-}
-
 static void iop_adma_free_chan_resources(struct dma_chan *chan)
 {
         struct iop_adma_chan *iop_chan = to_iop_adma_chan(chan);
@@ -854,11 +850,11 @@ static int __devinit iop_adma_memcpy_self_test(struct iop_adma_device *device)
         src_dma = dma_map_single(dma_chan->device->dev, src,
                                 IOP_ADMA_TEST_SIZE, DMA_TO_DEVICE);
         tx = iop_adma_prep_dma_memcpy(dma_chan, dest_dma, src_dma,
-                                      IOP_ADMA_TEST_SIZE, 1);
+                                      IOP_ADMA_TEST_SIZE,
+                                      DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
 
         cookie = iop_adma_tx_submit(tx);
         iop_adma_issue_pending(dma_chan);
-        async_tx_ack(tx);
         msleep(1);
 
         if (iop_adma_is_complete(dma_chan, cookie, NULL, NULL) !=
@@ -954,11 +950,11 @@ iop_adma_xor_zero_sum_self_test(struct iop_adma_device *device)
                 dma_srcs[i] = dma_map_page(dma_chan->device->dev, xor_srcs[i],
                                            0, PAGE_SIZE, DMA_TO_DEVICE);
         tx = iop_adma_prep_dma_xor(dma_chan, dest_dma, dma_srcs,
-                                   IOP_ADMA_NUM_SRC_TEST, PAGE_SIZE, 1);
+                                   IOP_ADMA_NUM_SRC_TEST, PAGE_SIZE,
+                                   DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
 
         cookie = iop_adma_tx_submit(tx);
         iop_adma_issue_pending(dma_chan);
-        async_tx_ack(tx);
         msleep(8);
 
         if (iop_adma_is_complete(dma_chan, cookie, NULL, NULL) !=
@@ -1001,11 +997,11 @@ iop_adma_xor_zero_sum_self_test(struct iop_adma_device *device)
                                            DMA_TO_DEVICE);
         tx = iop_adma_prep_dma_zero_sum(dma_chan, dma_srcs,
                                         IOP_ADMA_NUM_SRC_TEST + 1, PAGE_SIZE,
-                                        &zero_sum_result, 1);
+                                        &zero_sum_result,
+                                        DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
 
         cookie = iop_adma_tx_submit(tx);
         iop_adma_issue_pending(dma_chan);
-        async_tx_ack(tx);
         msleep(8);
 
         if (iop_adma_is_complete(dma_chan, cookie, NULL, NULL) != DMA_SUCCESS) {
@@ -1025,11 +1021,11 @@ iop_adma_xor_zero_sum_self_test(struct iop_adma_device *device)
         /* test memset */
         dma_addr = dma_map_page(dma_chan->device->dev, dest, 0,
                         PAGE_SIZE, DMA_FROM_DEVICE);
-        tx = iop_adma_prep_dma_memset(dma_chan, dma_addr, 0, PAGE_SIZE, 1);
+        tx = iop_adma_prep_dma_memset(dma_chan, dma_addr, 0, PAGE_SIZE,
+                                      DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
 
         cookie = iop_adma_tx_submit(tx);
         iop_adma_issue_pending(dma_chan);
-        async_tx_ack(tx);
         msleep(8);
 
         if (iop_adma_is_complete(dma_chan, cookie, NULL, NULL) != DMA_SUCCESS) {
@@ -1057,11 +1053,11 @@ iop_adma_xor_zero_sum_self_test(struct iop_adma_device *device)
                                            DMA_TO_DEVICE);
         tx = iop_adma_prep_dma_zero_sum(dma_chan, dma_srcs,
                                         IOP_ADMA_NUM_SRC_TEST + 1, PAGE_SIZE,
-                                        &zero_sum_result, 1);
+                                        &zero_sum_result,
+                                        DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
 
         cookie = iop_adma_tx_submit(tx);
         iop_adma_issue_pending(dma_chan);
-        async_tx_ack(tx);
         msleep(8);
 
         if (iop_adma_is_complete(dma_chan, cookie, NULL, NULL) != DMA_SUCCESS) {
@@ -1177,7 +1173,6 @@ static int __devinit iop_adma_probe(struct platform_device *pdev)
         dma_dev->device_free_chan_resources = iop_adma_free_chan_resources;
         dma_dev->device_is_tx_complete = iop_adma_is_complete;
         dma_dev->device_issue_pending = iop_adma_issue_pending;
-        dma_dev->device_dependency_added = iop_adma_dependency_added;
         dma_dev->dev = &pdev->dev;
 
         /* set prep routines based on capability */
@@ -1232,9 +1227,6 @@ static int __devinit iop_adma_probe(struct platform_device *pdev)
         }
 
         spin_lock_init(&iop_chan->lock);
-        init_timer(&iop_chan->cleanup_watchdog);
-        iop_chan->cleanup_watchdog.data = (unsigned long) iop_chan;
-        iop_chan->cleanup_watchdog.function = iop_adma_tasklet;
         INIT_LIST_HEAD(&iop_chan->chain);
         INIT_LIST_HEAD(&iop_chan->all_slots);
         INIT_RCU_HEAD(&iop_chan->common.rcu);
@@ -1298,7 +1290,7 @@ static void iop_chan_start_null_memcpy(struct iop_adma_chan *iop_chan)
                 grp_start = sw_desc->group_head;
 
                 list_splice_init(&sw_desc->async_tx.tx_list, &iop_chan->chain);
-                sw_desc->async_tx.ack = 1;
+                async_tx_ack(&sw_desc->async_tx);
                 iop_desc_init_memcpy(grp_start, 0);
                 iop_desc_set_byte_count(grp_start, iop_chan, 0);
                 iop_desc_set_dest_addr(grp_start, iop_chan, 0);
@@ -1354,7 +1346,7 @@ static void iop_chan_start_null_xor(struct iop_adma_chan *iop_chan)
         if (sw_desc) {
                 grp_start = sw_desc->group_head;
                 list_splice_init(&sw_desc->async_tx.tx_list, &iop_chan->chain);
-                sw_desc->async_tx.ack = 1;
+                async_tx_ack(&sw_desc->async_tx);
                 iop_desc_init_null_xor(grp_start, 2, 0);
                 iop_desc_set_byte_count(grp_start, iop_chan, 0);
                 iop_desc_set_dest_addr(grp_start, iop_chan, 0);
diff --git a/include/asm-arm/arch-iop13xx/adma.h b/include/asm-arm/arch-iop13xx/adma.h
index efd9a5eb1008..90d14ee564f5 100644
--- a/include/asm-arm/arch-iop13xx/adma.h
+++ b/include/asm-arm/arch-iop13xx/adma.h
@@ -454,11 +454,6 @@ static inline void iop_chan_append(struct iop_adma_chan *chan)
         __raw_writel(adma_accr, ADMA_ACCR(chan));
 }
 
-static inline void iop_chan_idle(int busy, struct iop_adma_chan *chan)
-{
-        do { } while (0);
-}
-
 static inline u32 iop_chan_get_status(struct iop_adma_chan *chan)
 {
         return __raw_readl(ADMA_ACSR(chan));
diff --git a/include/asm-arm/hardware/iop3xx-adma.h b/include/asm-arm/hardware/iop3xx-adma.h
index 5c529e6a5e3b..84d635b0a71a 100644
--- a/include/asm-arm/hardware/iop3xx-adma.h
+++ b/include/asm-arm/hardware/iop3xx-adma.h
@@ -767,20 +767,12 @@ static inline int iop_desc_get_zero_result(struct iop_adma_desc_slot *desc)
 static inline void iop_chan_append(struct iop_adma_chan *chan)
 {
         u32 dma_chan_ctrl;
-        /* workaround dropped interrupts on 3xx */
-        mod_timer(&chan->cleanup_watchdog, jiffies + msecs_to_jiffies(3));
 
         dma_chan_ctrl = __raw_readl(DMA_CCR(chan));
         dma_chan_ctrl |= 0x2;
         __raw_writel(dma_chan_ctrl, DMA_CCR(chan));
 }
 
-static inline void iop_chan_idle(int busy, struct iop_adma_chan *chan)
-{
-        if (!busy)
-                del_timer(&chan->cleanup_watchdog);
-}
-
 static inline u32 iop_chan_get_status(struct iop_adma_chan *chan)
 {
         return __raw_readl(DMA_CSR(chan));
diff --git a/include/asm-arm/hardware/iop_adma.h b/include/asm-arm/hardware/iop_adma.h
index ca8e71f44346..cb7e3611bcba 100644
--- a/include/asm-arm/hardware/iop_adma.h
+++ b/include/asm-arm/hardware/iop_adma.h
@@ -51,7 +51,6 @@ struct iop_adma_device {
  * @common: common dmaengine channel object members
  * @last_used: place holder for allocation to continue from where it left off
  * @all_slots: complete domain of slots usable by the channel
- * @cleanup_watchdog: workaround missed interrupts on iop3xx
  * @slots_allocated: records the actual size of the descriptor slot pool
  * @irq_tasklet: bottom half where iop_adma_slot_cleanup runs
  */
@@ -65,7 +64,6 @@ struct iop_adma_chan {
         struct dma_chan common;
         struct iop_adma_desc_slot *last_used;
         struct list_head all_slots;
-        struct timer_list cleanup_watchdog;
         int slots_allocated;
         struct tasklet_struct irq_tasklet;
 };
diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h
index 34d440698293..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
@@ -221,23 +226,20 @@ typedef void (*dma_async_tx_callback)(void *dma_async_param);
  * @callback: routine to call after this operation is complete
  * @callback_param: general parameter to pass to the callback routine
  * ---async_tx api specific fields---
- * @depend_list: at completion this list of transactions are submitted
- * @depend_node: allow this transaction to be executed after another
- *      transaction has completed, possibly on another channel
+ * @next: at completion submit this descriptor
  * @parent: pointer to the next level up in the dependency chain
- * @lock: protect the dependency list
+ * @lock: protect the parent and next pointers
  */
 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;
         dma_cookie_t (*tx_submit)(struct dma_async_tx_descriptor *tx);
         dma_async_tx_callback callback;
         void *callback_param;
-        struct list_head depend_list;
-        struct list_head depend_node;
+        struct dma_async_tx_descriptor *next;
         struct dma_async_tx_descriptor *parent;
         spinlock_t lock;
 };
@@ -261,7 +263,6 @@ struct dma_async_tx_descriptor {
  * @device_prep_dma_zero_sum: prepares a zero_sum operation
  * @device_prep_dma_memset: prepares a memset operation
  * @device_prep_dma_interrupt: prepares an end of chain interrupt operation
- * @device_dependency_added: async_tx notifies the channel about new deps
  * @device_issue_pending: push pending transactions to hardware
  */
 struct dma_device {
@@ -294,9 +295,8 @@ 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);
 
-        void (*device_dependency_added)(struct dma_chan *chan);
         enum dma_status (*device_is_tx_complete)(struct dma_chan *chan,
                         dma_cookie_t cookie, dma_cookie_t *last,
                         dma_cookie_t *used);
@@ -321,7 +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))