dmaengine: Add function to request slave channel from a dma_device

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@ti.com>

drivers/dma/dmaengine.c

@@ -615,7 +615,8 @@ 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)
+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;
@@ -626,13 +627,13 @@ struct dma_chan *dma_get_any_slave_channel(struct dma_device *device)
 	/* lock against __dma_request_channel */
 	mutex_lock(&dma_list_mutex);
 
-	chan = find_candidate(device, &mask, NULL, NULL);
+	chan = find_candidate(device, &mask, fn, fn_param);
 
 	mutex_unlock(&dma_list_mutex);
 
 	return IS_ERR(chan) ? NULL : chan;
 }
-EXPORT_SYMBOL_GPL(dma_get_any_slave_channel);
+EXPORT_SYMBOL_GPL(dmadev_get_slave_channel);
 
 /**
  * __dma_request_channel - try to allocate an exclusive channel

include/linux/dmaengine.h

@@ -1520,7 +1520,10 @@ int dmaenginem_async_device_register(struct dma_device *device);
 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_get_any_slave_channel(device) \
+	dmadev_get_slave_channel(device, NULL, NULL)
 #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)