Merge branch 'next' of git://git.infradead.org/users/vkoul/slave-dma

Pull slave-dmaengine updates from Vinod Koul:
 "This is fairly big pull by my standards as I had missed last merge
  window.  So we have the support for device tree for slave-dmaengine,
  large updates to dw_dmac driver from Andy for reusing on different
  architectures.  Along with this we have fixes on bunch of the drivers"

Fix up trivial conflicts, usually due to #include line movement next to
each other.

* 'next' of git://git.infradead.org/users/vkoul/slave-dma: (111 commits)
  Revert "ARM: SPEAr13xx: Pass DW DMAC platform data from DT"
  ARM: dts: pl330: Add #dma-cells for generic dma binding support
  DMA: PL330: Register the DMA controller with the generic DMA helpers
  DMA: PL330: Add xlate function
  DMA: PL330: Add new pl330 filter for DT case.
  dma: tegra20-apb-dma: remove unnecessary assignment
  edma: do not waste memory for dma_mask
  dma: coh901318: set residue only if dma is in progress
  dma: coh901318: avoid unbalanced locking
  dmaengine.h: remove redundant else keyword
  dma: of-dma: protect list write operation by spin_lock
  dmaengine: ste_dma40: do not remove descriptors for cyclic transfers
  dma: of-dma.c: fix memory leakage
  dw_dmac: apply default dma_mask if needed
  dmaengine: ioat - fix spare sparse complain
  dmaengine: move drivers/of/dma.c -> drivers/dma/of-dma.c
  ioatdma: fix race between updating ioat->head and IOAT_COMPLETION_PENDING
  dw_dmac: add support for Lynxpoint DMA controllers
  dw_dmac: return proper residue value
  dw_dmac: fill individual length of descriptor
  ...

1 files changed, 20 insertions, 1 deletions

diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c
index a815d44c70a4..242b8c0a3de8 100644
--- a/drivers/dma/dmaengine.c
+++ b/drivers/dma/dmaengine.c
@@ -62,6 +62,7 @@
 #include <linux/rculist.h>
 #include <linux/idr.h>
 #include <linux/slab.h>
+#include <linux/of_dma.h>
 
 static DEFINE_MUTEX(dma_list_mutex);
 static DEFINE_IDR(dma_idr);
@@ -266,7 +267,10 @@ enum dma_status dma_sync_wait(struct dma_chan *chan, dma_cookie_t cookie)
 			pr_err("%s: timeout!\n", __func__);
 			return DMA_ERROR;
 		}
-	} while (status == DMA_IN_PROGRESS);
+		if (status != DMA_IN_PROGRESS)
+			break;
+		cpu_relax();
+	} while (1);
 
 	return status;
 }
@@ -546,6 +550,21 @@ struct dma_chan *__dma_request_channel(dma_cap_mask_t *mask, dma_filter_fn fn, v
 }
 EXPORT_SYMBOL_GPL(__dma_request_channel);
 
+/**
+ * dma_request_slave_channel - try to allocate an exclusive slave channel
+ * @dev:	pointer to client device structure
+ * @name:	slave channel name
+ */
+struct dma_chan *dma_request_slave_channel(struct device *dev, char *name)
+{
+	/* If device-tree is present get slave info from here */
+	if (dev->of_node)
+		return of_dma_request_slave_channel(dev->of_node, name);
+
+	return NULL;
+}
+EXPORT_SYMBOL_GPL(dma_request_slave_channel);
+
 void dma_release_channel(struct dma_chan *chan)
 {
 	mutex_lock(&dma_list_mutex);