[PATCH v5 05/61] dmaengine: Make channel allocation callbacks optional
From: Maxime Ripard <hidden>
Date: 2014-11-17 14:03:19
Also in:
lkml
Subsystem:
dma generic offload engine subsystem, the rest · Maintainers:
Vinod Koul, Linus Torvalds
Nowadays, some drivers don't have anything in there channel allocation callbacks anymore. Remove the BUG_ON if those callbacks aren't implemented, in order to allow drivers to not implement them. Signed-off-by: Maxime Ripard <redacted> Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> --- drivers/dma/dmaengine.c | 18 +++++++++++------- 1 file changed, 11 insertions(+), 7 deletions(-)
diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c
index 72f10e2f5c32..9b2cd74b8f2e 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); }
@@ -819,8 +825,6 @@ 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);
--
2.1.1