1 files changed, 32 insertions, 7 deletions

diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c
index 92caad629d9..d5d30ed863c 100644
--- a/drivers/dma/dmaengine.c
+++ b/drivers/dma/dmaengine.c
@@ -535,6 +535,34 @@ struct dma_chan *dma_get_slave_channel(struct dma_chan *chan)
 }
 EXPORT_SYMBOL_GPL(dma_get_slave_channel);
 
+struct dma_chan *dma_get_any_slave_channel(struct dma_device *device)
+{
+	dma_cap_mask_t mask;
+	struct dma_chan *chan;
+	int err;
+
+	dma_cap_zero(mask);
+	dma_cap_set(DMA_SLAVE, mask);
+
+	/* lock against __dma_request_channel */
+	mutex_lock(&dma_list_mutex);
+
+	chan = private_candidate(&mask, device, NULL, NULL);
+	if (chan) {
+		err = dma_chan_get(chan);
+		if (err) {
+			pr_debug("%s: failed to get %s: (%d)\n",
+				__func__, dma_chan_name(chan), err);
+			chan = NULL;
+		}
+	}
+
+	mutex_unlock(&dma_list_mutex);
+
+	return chan;
+}
+EXPORT_SYMBOL_GPL(dma_get_any_slave_channel);
+
 /**
  * __dma_request_channel - try to allocate an exclusive channel
  * @mask: capabilities that the channel must satisfy
@@ -599,18 +627,13 @@ EXPORT_SYMBOL_GPL(__dma_request_channel);
 struct dma_chan *dma_request_slave_channel_reason(struct device *dev,
 						  const char *name)
 {
-	struct dma_chan *chan;
-
 	/* If device-tree is present get slave info from here */
 	if (dev->of_node)
 		return of_dma_request_slave_channel(dev->of_node, name);
 
 	/* If device was enumerated by ACPI get slave info from here */
-	if (ACPI_HANDLE(dev)) {
-		chan = acpi_dma_request_slave_chan_by_name(dev, name);
-		if (chan)
-			return chan;
-	}
+	if (ACPI_HANDLE(dev))
+		return acpi_dma_request_slave_chan_by_name(dev, name);
 
 	return ERR_PTR(-ENODEV);
 }
@@ -986,6 +1009,7 @@ static void dmaengine_unmap(struct kref *kref)
 		dma_unmap_page(dev, unmap->addr[i], unmap->len,
 			       DMA_BIDIRECTIONAL);
 	}
+	cnt = unmap->map_cnt;
 	mempool_free(unmap, __get_unmap_pool(cnt)->pool);
 }
 
@@ -1051,6 +1075,7 @@ dmaengine_get_unmap_data(struct device *dev, int nr, gfp_t flags)
 	memset(unmap, 0, sizeof(*unmap));
 	kref_init(&unmap->kref);
 	unmap->dev = dev;
+	unmap->map_cnt = nr;
 
 	return unmap;
 }