Am 08.12.2014 um 12:07 schrieb Julian Scheel:
As dma_get_any_slave_channel is used to request a channel which will later on
be released through dma_release_channel it needs to maintain the privatecnt
just as __dma_request_channel does. Do this by refactoring the privatenct
handling into a helper function which is used from __dma_request_channel as
well as dma_get_any_slave_channel.
Signed-off-by: Julian Scheel <julian@xxxxxxxx>
---
drivers/dma/dmaengine.c | 30 +++++++++++++++++++++---------
1 file changed, 21 insertions(+), 9 deletions(-)
diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c
index 24bfaf0..0215db4 100644
--- a/drivers/dma/dmaengine.c
+++ b/drivers/dma/dmaengine.c
@@ -535,6 +535,24 @@ struct dma_chan *dma_get_slave_channel(struct dma_chan *chan)
}
EXPORT_SYMBOL_GPL(dma_get_slave_channel);
+
+static int dma_get_channel_private(struct dma_device *device, struct dma_chan *chan)
+{
+ int err;
+
+ /* We first set DMA_PRIVATE to disable
+ * balance_ref_count as this channel will not be
+ * published in the general-purpose allocator
+ */
+ dma_cap_set(DMA_PRIVATE, device->cap_mask);
+ device->privatecnt++;
+
+ err = dma_chan_get(chan);
+ if (err && --device->privatecnt == 0)
+ dma_cap_clear(DMA_PRIVATE, device->cap_mask);
+ return err;
+}
+
struct dma_chan *dma_get_any_slave_channel(struct dma_device *device)
{
dma_cap_mask_t mask;
@@ -549,7 +567,7 @@ struct dma_chan *dma_get_any_slave_channel(struct dma_device *device)
chan = private_candidate(&mask, device, NULL, NULL);
if (chan) {
- err = dma_chan_get(chan);
+ err = dma_get_channel_private(device, chan);
if (err) {
pr_debug("%s: failed to get %s: (%d)\n",
__func__, dma_chan_name(chan), err);
@@ -584,13 +602,9 @@ struct dma_chan *__dma_request_channel(const dma_cap_mask_t *mask,
chan = private_candidate(mask, device, fn, fn_param);
if (chan) {
/* Found a suitable channel, try to grab, prep, and
- * return it. We first set DMA_PRIVATE to disable
- * balance_ref_count as this channel will not be
- * published in the general-purpose allocator
+ * return it.
*/
- dma_cap_set(DMA_PRIVATE, device->cap_mask);
- device->privatecnt++;
- err = dma_chan_get(chan);
+ err = dma_get_channel_private(device, chan);
if (err == -ENODEV) {
pr_debug("%s: %s module removed\n",
@@ -601,8 +615,6 @@ struct dma_chan *__dma_request_channel(const dma_cap_mask_t *mask,
__func__, dma_chan_name(chan), err);
else
break;
- if (--device->privatecnt == 0)
- dma_cap_clear(DMA_PRIVATE, device->cap_mask);
chan = NULL;
}
}
Any objections on this patch?
-Julian
--
To unsubscribe from this list: send the line "unsubscribe dmaengine" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
