1 files changed, 11 insertions, 2 deletions

diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c
index 3ddfd1f6c23c..4a4cce15f25d 100644
--- a/drivers/dma/dmaengine.c
+++ b/drivers/dma/dmaengine.c
@@ -267,6 +267,13 @@ static void dma_chan_put(struct dma_chan *chan)
         /* This channel is not in use anymore, free it */
         if (!chan->client_count && chan->device->device_free_chan_resources)
                 chan->device->device_free_chan_resources(chan);
+
+        /* If the channel is used via a DMA request router, free the mapping */
+        if (chan->router && chan->router->route_free) {
+                chan->router->route_free(chan->router->dev, chan->route_data);
+                chan->router = NULL;
+                chan->route_data = NULL;
+        }
 }
 
 enum dma_status dma_sync_wait(struct dma_chan *chan, dma_cookie_t cookie)
@@ -536,7 +543,7 @@ static struct dma_chan *private_candidate(const dma_cap_mask_t *mask,
 }
 
 /**
- * dma_request_slave_channel - try to get specific channel exclusively
+ * dma_get_slave_channel - try to get specific channel exclusively
  * @chan: target channel
  */
 struct dma_chan *dma_get_slave_channel(struct dma_chan *chan)
@@ -648,7 +655,7 @@ struct dma_chan *__dma_request_channel(const dma_cap_mask_t *mask,
 EXPORT_SYMBOL_GPL(__dma_request_channel);
 
 /**
- * dma_request_slave_channel - try to allocate an exclusive slave channel
+ * dma_request_slave_channel_reason - try to allocate an exclusive slave channel
  * @dev:        pointer to client device structure
  * @name:       slave channel name
  *
@@ -836,6 +843,8 @@ int dma_async_device_register(struct dma_device *device)
                 !device->device_prep_dma_pq);
         BUG_ON(dma_has_cap(DMA_PQ_VAL, device->cap_mask) &&
                 !device->device_prep_dma_pq_val);
+        BUG_ON(dma_has_cap(DMA_MEMSET, device->cap_mask) &&
+                !device->device_prep_dma_memset);
         BUG_ON(dma_has_cap(DMA_INTERRUPT, device->cap_mask) &&
                 !device->device_prep_dma_interrupt);
         BUG_ON(dma_has_cap(DMA_SG, device->cap_mask) &&