dmaengine: increment privatecnt when using dma_get_any_slave_channel
authorChristopher Freeman <cfreeman@nvidia.com>
Wed, 4 Mar 2015 09:16:58 +0000 (01:16 -0800)
committerVinod Koul <vinod.koul@intel.com>
Wed, 29 Apr 2015 11:17:57 +0000 (16:47 +0530)
Channels allocated via dma_get_any_slave_channel were not increasing
the counter tracking private allocations.  When these channels were
released, privatecnt may erroneously fall to zero.  The DMA device
would then lose its DMA_PRIVATE cap and fail to allocate future private
channels (via private_candidate) as any allocations still outstanding
would incorrectly be seen as public allocations.

Signed-off-by: Christopher Freeman <cfreeman@nvidia.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
drivers/dma/dmaengine.c

index 0e035a8..2890d74 100644 (file)
@@ -571,11 +571,15 @@ struct dma_chan *dma_get_any_slave_channel(struct dma_device *device)
 
        chan = private_candidate(&mask, device, NULL, NULL);
        if (chan) {
+               dma_cap_set(DMA_PRIVATE, device->cap_mask);
+               device->privatecnt++;
                err = dma_chan_get(chan);
                if (err) {
                        pr_debug("%s: failed to get %s: (%d)\n",
                                __func__, dma_chan_name(chan), err);
                        chan = NULL;
+                       if (--device->privatecnt == 0)
+                               dma_cap_clear(DMA_PRIVATE, device->cap_mask);
                }
        }