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authorStephen Warren <swarren@nvidia.com>2013-11-26 12:40:51 -0700
committerVinod Koul <vinod.koul@intel.com>2013-12-10 17:48:33 +0530
commit8010dad55a0ab0e829f3733854e5235eef4e2734 (patch)
tree1a853cb6960763860227891b1324ab9467d6e8c9 /drivers/dma/dmaengine.c
parent6ce4eac1f600b34f2f7f58f9cd8f0503d79e42ae (diff)
downloadlinux-8010dad55a0ab0e829f3733854e5235eef4e2734.tar.bz2
dma: add dma_get_any_slave_channel(), for use in of_xlate()
mmp_pdma.c implements a custom of_xlate() function that is 95% identical to what Tegra will need. Create a function to implement the common part, so everyone doesn't just cut/paste the implementation. Cc: Dan Williams <dan.j.williams@intel.com> Cc: Vinod Koul <vinod.koul@intel.com> Cc: Lars-Peter Clausen <lars@metafoo.de> Cc: dmaengine@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Diffstat (limited to 'drivers/dma/dmaengine.c')
-rw-r--r--drivers/dma/dmaengine.c28
1 files changed, 28 insertions, 0 deletions
diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c
index ea806bdc12ef..4f08ee8c17b4 100644
--- a/drivers/dma/dmaengine.c
+++ b/drivers/dma/dmaengine.c
@@ -535,6 +535,34 @@ struct dma_chan *dma_get_slave_channel(struct dma_chan *chan)
}
EXPORT_SYMBOL_GPL(dma_get_slave_channel);
+struct dma_chan *dma_get_any_slave_channel(struct dma_device *device)
+{
+ dma_cap_mask_t mask;
+ struct dma_chan *chan;
+ int err;
+
+ dma_cap_zero(mask);
+ dma_cap_set(DMA_SLAVE, mask);
+
+ /* lock against __dma_request_channel */
+ mutex_lock(&dma_list_mutex);
+
+ chan = private_candidate(&mask, device, NULL, NULL);
+ if (chan) {
+ err = dma_chan_get(chan);
+ if (err) {
+ pr_debug("%s: failed to get %s: (%d)\n",
+ __func__, dma_chan_name(chan), err);
+ chan = NULL;
+ }
+ }
+
+ mutex_unlock(&dma_list_mutex);
+
+ return chan;
+}
+EXPORT_SYMBOL_GPL(dma_get_any_slave_channel);
+
/**
* __dma_request_channel - try to allocate an exclusive channel
* @mask: capabilities that the channel must satisfy