diff options
Diffstat (limited to 'drivers/dma/dmaengine.c')
| -rw-r--r-- | drivers/dma/dmaengine.c | 18 |
1 files changed, 11 insertions, 7 deletions
diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c index a5da0e147560..b7f09f63a160 100644 --- a/drivers/dma/dmaengine.c +++ b/drivers/dma/dmaengine.c @@ -235,9 +235,11 @@ static int dma_chan_get(struct dma_chan *chan) return -ENODEV; /* allocate upon first client reference */ - ret = chan->device->device_alloc_chan_resources(chan); - if (ret < 0) - goto err_out; + if (chan->device->device_alloc_chan_resources) { + ret = chan->device->device_alloc_chan_resources(chan); + if (ret < 0) + goto err_out; + } if (!dma_has_cap(DMA_PRIVATE, chan->device->cap_mask)) balance_ref_count(chan); @@ -259,11 +261,15 @@ err_out: */ static void dma_chan_put(struct dma_chan *chan) { + /* This channel is not in use, bail out */ if (!chan->client_count) - return; /* this channel failed alloc_chan_resources */ + return; + chan->client_count--; module_put(dma_chan_to_owner(chan)); - if (chan->client_count == 0) + + /* 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); } @@ -818,8 +824,6 @@ int dma_async_device_register(struct dma_device *device) BUG_ON(dma_has_cap(DMA_INTERLEAVE, device->cap_mask) && !device->device_prep_interleaved_dma); - BUG_ON(!device->device_alloc_chan_resources); - BUG_ON(!device->device_free_chan_resources); BUG_ON(!device->device_tx_status); BUG_ON(!device->device_issue_pending); BUG_ON(!device->dev); |