diff options
| author | Timur Tabi <timur@freescale.com> | 2008-09-19 04:16:19 -0700 |
|---|---|---|
| committer | Dan Williams <dan.j.williams@intel.com> | 2008-09-19 04:16:19 -0700 |
| commit | 6b3141962dc82cfe1c30afdf91d564b309859cbe (patch) | |
| tree | 51a0045ba900f44083fbd2693824414262534dbc /drivers/dma/dmatest.c | |
| parent | 89f72a0633d1d4f28c4c5c8831ec814523d7671a (diff) | |
dmatest: properly handle duplicate DMA channels
Update the the dmatest driver so that it handles duplicate DMA channels
properly.
When a DMA client is notified of an available DMA channel, it must check if it
has already allocated resources for that channel. If so, it should return
DMA_DUP. This can happen, for example, if a DMA driver calls
dma_async_device_register() more than once.
Acked-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
Signed-off-by: Timur Tabi <timur@freescale.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Diffstat (limited to 'drivers/dma/dmatest.c')
| -rw-r--r-- | drivers/dma/dmatest.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/drivers/dma/dmatest.c b/drivers/dma/dmatest.c index a08d19704743..422500c6c163 100644 --- a/drivers/dma/dmatest.c +++ b/drivers/dma/dmatest.c @@ -325,6 +325,11 @@ static enum dma_state_client dmatest_add_channel(struct dma_chan *chan) struct dmatest_thread *thread; unsigned int i; + /* Have we already been told about this channel? */ + list_for_each_entry(dtc, &dmatest_channels, node) + if (dtc->chan == chan) + return DMA_DUP; + dtc = kmalloc(sizeof(struct dmatest_chan), GFP_ATOMIC); if (!dtc) { pr_warning("dmatest: No memory for %s\n", chan->dev.bus_id); |