dma_get_any_slave_channel() would skip using the filter function, which
in some cases needed to be executed before the alloc_chan_resources
callback to make sure that all parameters are provided for the slave
channel.
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@xxxxxx>
---
drivers/dma/dmaengine.c | 20 ++++++++++++++++++++
include/linux/dmaengine.h | 2 ++
2 files changed, 22 insertions(+)
diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c
index 27b6d7c2d8a0..b80f1bdd8813 100644
--- a/drivers/dma/dmaengine.c
+++ b/drivers/dma/dmaengine.c
@@ -634,6 +634,26 @@ struct dma_chan *dma_get_any_slave_channel(struct dma_device *device)
}
EXPORT_SYMBOL_GPL(dma_get_any_slave_channel);
+struct dma_chan *dmadev_get_slave_channel(struct dma_device *device,
+ dma_filter_fn fn, void *fn_param)
+{
+ dma_cap_mask_t mask;
+ struct dma_chan *chan;
+
+ dma_cap_zero(mask);
+ dma_cap_set(DMA_SLAVE, mask);
+
+ /* lock against __dma_request_channel */
+ mutex_lock(&dma_list_mutex);
+
+ chan = find_candidate(device, &mask, fn, fn_param);
+
+ mutex_unlock(&dma_list_mutex);
+
+ return IS_ERR(chan) ? NULL : chan;
+}
+EXPORT_SYMBOL_GPL(dmadev_get_slave_channel);
+
/**
* __dma_request_channel - try to allocate an exclusive channel
* @mask: capabilities that the channel must satisfy
diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h
index 16c9d021988a..32010c6ae13a 100644
--- a/include/linux/dmaengine.h
+++ b/include/linux/dmaengine.h
@@ -1542,6 +1542,8 @@ void dma_async_device_unregister(struct dma_device *device);
void dma_run_dependencies(struct dma_async_tx_descriptor *tx);
struct dma_chan *dma_get_slave_channel(struct dma_chan *chan);
struct dma_chan *dma_get_any_slave_channel(struct dma_device *device);
+struct dma_chan *dmadev_get_slave_channel(struct dma_device *device,
+ dma_filter_fn fn, void *fn_param);
#define dma_request_channel(mask, x, y) __dma_request_channel(&(mask), x, y)
#define dma_request_slave_channel_compat(mask, x, y, dev, name) \
__dma_request_slave_channel_compat(&(mask), x, y, dev, name)
--
Peter
Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki.
Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki
