summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorLars-Peter Clausen <lars@metafoo.de>2015-10-20 11:46:29 +0200
committerVinod Koul <vinod.koul@intel.com>2015-11-16 08:28:52 +0530
commit2ed086296e60c3ca9a63a025701f4d104f4ced85 (patch)
tree207a0607ec8caac6657d070d5dc1033750849299
parentb36f09c3c441a6e59eab9315032e7d546571de3f (diff)
dmaengine: virt-dma: Add synchronization helper function
Add a synchronize helper function for the virt-dma library. The function makes sure that any scheduled descriptor complete callbacks have finished running before the function returns. This needs to be called by drivers using virt-dma in their device_synchronize() callback. Depending on the driver additional operations might be necessary in addition to calling vchan_synchronize() to ensure proper synchronization. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
-rw-r--r--drivers/dma/virt-dma.h13
1 files changed, 13 insertions, 0 deletions
diff --git a/drivers/dma/virt-dma.h b/drivers/dma/virt-dma.h
index 2fa47745a41f..edbb5751572b 100644
--- a/drivers/dma/virt-dma.h
+++ b/drivers/dma/virt-dma.h
@@ -151,4 +151,17 @@ static inline void vchan_free_chan_resources(struct virt_dma_chan *vc)
vchan_dma_desc_free_list(vc, &head);
}
+/**
+ * vchan_synchronize() - synchronize callback execution to the current context
+ * @vc: virtual channel to synchronize
+ *
+ * Makes sure that all scheduled or active callbacks have finished running. For
+ * proper operation the caller has to ensure that no new callbacks are scheduled
+ * after the invocation of this function started.
+ */
+static inline void vchan_synchronize(struct virt_dma_chan *vc)
+{
+ tasklet_kill(&vc->task);
+}
+
#endif