diff options
author | Stephen Warren <swarren@nvidia.com> | 2013-11-26 12:40:51 -0700 |
---|---|---|
committer | Vinod Koul <vinod.koul@intel.com> | 2013-12-10 17:48:33 +0530 |
commit | 8010dad55a0ab0e829f3733854e5235eef4e2734 (patch) | |
tree | 1a853cb6960763860227891b1324ab9467d6e8c9 /drivers | |
parent | 6ce4eac1f600b34f2f7f58f9cd8f0503d79e42ae (diff) | |
download | op-kernel-dev-8010dad55a0ab0e829f3733854e5235eef4e2734.zip op-kernel-dev-8010dad55a0ab0e829f3733854e5235eef4e2734.tar.gz |
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')
-rw-r--r-- | drivers/dma/dmaengine.c | 28 | ||||
-rw-r--r-- | drivers/dma/mmp_pdma.c | 30 |
2 files changed, 35 insertions, 23 deletions
diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c index ea806bd..4f08ee8 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 diff --git a/drivers/dma/mmp_pdma.c b/drivers/dma/mmp_pdma.c index dcb1e05..2998f1b 100644 --- a/drivers/dma/mmp_pdma.c +++ b/drivers/dma/mmp_pdma.c @@ -893,33 +893,17 @@ static struct dma_chan *mmp_pdma_dma_xlate(struct of_phandle_args *dma_spec, struct of_dma *ofdma) { struct mmp_pdma_device *d = ofdma->of_dma_data; - struct dma_chan *chan, *candidate; + struct dma_chan *chan; + struct mmp_pdma_chan *c; -retry: - candidate = NULL; - - /* walk the list of channels registered with the current instance and - * find one that is currently unused */ - list_for_each_entry(chan, &d->device.channels, device_node) - if (chan->client_count == 0) { - candidate = chan; - break; - } - - if (!candidate) + chan = dma_get_any_slave_channel(&d->device); + if (!chan) return NULL; - /* dma_get_slave_channel will return NULL if we lost a race between - * the lookup and the reservation */ - chan = dma_get_slave_channel(candidate); - - if (chan) { - struct mmp_pdma_chan *c = to_mmp_pdma_chan(chan); - c->drcmr = dma_spec->args[0]; - return chan; - } + c = to_mmp_pdma_chan(chan); + c->drcmr = dma_spec->args[0]; - goto retry; + return chan; } static int mmp_pdma_probe(struct platform_device *op) |