DMA: PL330: Add xlate function

Add xlate to translate the device-tree binding information into
the appropriate format. The filter function requires the dma
controller device and dma channel number as filter_params.

Signed-off-by: Padmavathi Venna <[e-mail]>
Acked-by: Arnd Bergmann <[e-mail]>
Signed-off-by: Vinod Koul <[e-mail]>

drivers/dma/pl330.c

···
 #include <linux/amba/pl330.h>
 #include <linux/scatterlist.h>
 #include <linux/of.h>
+#include <linux/of_dma.h>
 
 #include "dmaengine.h"
 #define PL330_MAX_CHAN		8
···
 	return *peri_id == (unsigned)param;
 }
 EXPORT_SYMBOL(pl330_filter);
+
+static struct dma_chan *of_dma_pl330_xlate(struct of_phandle_args *dma_spec,
+						struct of_dma *ofdma)
+{
+	int count = dma_spec->args_count;
+	struct dma_pl330_dmac *pdmac = ofdma->of_dma_data;
+	struct dma_pl330_filter_args fargs;
+	dma_cap_mask_t cap;
+
+	if (!pdmac)
+		return NULL;
+
+	if (count != 1)
+		return NULL;
+
+	fargs.pdmac = pdmac;
+	fargs.chan_id = dma_spec->args[0];
+
+	dma_cap_zero(cap);
+	dma_cap_set(DMA_SLAVE, cap);
+	dma_cap_set(DMA_CYCLIC, cap);
+
+	return dma_request_channel(cap, pl330_dt_filter, &fargs);
+}
 
 static int pl330_alloc_chan_resources(struct dma_chan *chan)
 {