summaryrefslogtreecommitdiffstats
path: root/drivers/dma/dmaengine.c
diff options
context:
space:
mode:
authorMark Brown <broonie@linaro.org>2014-01-02 13:01:52 +0000
committerMark Brown <broonie@linaro.org>2014-01-02 13:01:52 +0000
commit75aac8206006e70859930d356ccfe02543530c27 (patch)
tree3d7581b0dd992da0661a1eea81737d427ac81eb4 /drivers/dma/dmaengine.c
parent01ad154ea505aeda249a4db4140a276f3eae509b (diff)
parent2b67f8ba41ac7acf01c8d5c742c713ead8b589cd (diff)
downloadlinux-75aac8206006e70859930d356ccfe02543530c27.tar.bz2
Merge remote-tracking branch 'asoc/topic/dma' into asoc-next
Diffstat (limited to 'drivers/dma/dmaengine.c')
-rw-r--r--drivers/dma/dmaengine.c35
1 files changed, 31 insertions, 4 deletions
diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c
index ef63b9058f3c..92caad629d99 100644
--- a/drivers/dma/dmaengine.c
+++ b/drivers/dma/dmaengine.c
@@ -540,6 +540,8 @@ EXPORT_SYMBOL_GPL(dma_get_slave_channel);
* @mask: capabilities that the channel must satisfy
* @fn: optional callback to disposition available channels
* @fn_param: opaque parameter to pass to dma_filter_fn
+ *
+ * Returns pointer to appropriate DMA channel on success or NULL.
*/
struct dma_chan *__dma_request_channel(const dma_cap_mask_t *mask,
dma_filter_fn fn, void *fn_param)
@@ -591,18 +593,43 @@ 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
+ *
+ * Returns pointer to appropriate DMA channel on success or an error pointer.
*/
-struct dma_chan *dma_request_slave_channel(struct device *dev, const char *name)
+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))
- return acpi_dma_request_slave_chan_by_name(dev, name);
+ if (ACPI_HANDLE(dev)) {
+ chan = acpi_dma_request_slave_chan_by_name(dev, name);
+ if (chan)
+ return chan;
+ }
- return NULL;
+ return ERR_PTR(-ENODEV);
+}
+EXPORT_SYMBOL_GPL(dma_request_slave_channel_reason);
+
+/**
+ * dma_request_slave_channel - try to allocate an exclusive slave channel
+ * @dev: pointer to client device structure
+ * @name: slave channel name
+ *
+ * Returns pointer to appropriate DMA channel on success or NULL.
+ */
+struct dma_chan *dma_request_slave_channel(struct device *dev,
+ const char *name)
+{
+ struct dma_chan *ch = dma_request_slave_channel_reason(dev, name);
+ if (IS_ERR(ch))
+ return NULL;
+ return ch;
}
EXPORT_SYMBOL_GPL(dma_request_slave_channel);