2 files changed, 35 insertions, 1 deletions

diff --git a/drivers/dma/mmp_pdma.c b/drivers/dma/mmp_pdma.c
index eb75d4b4bafe..dd024d4759e7 100644
--- a/drivers/dma/mmp_pdma.c
+++ b/drivers/dma/mmp_pdma.c
@@ -19,6 +19,7 @@
 #include <linux/dmapool.h>
 #include <linux/of_device.h>
 #include <linux/of.h>
+#include <linux/dma/mmp-pdma.h>
 
 #include "dmaengine.h"
 
@@ -635,8 +636,13 @@ static int mmp_pdma_control(struct dma_chan *dchan, enum dma_ctrl_cmd cmd,
                         chan->dcmd |= DCMD_BURST32;
 
                 chan->dir = cfg->direction;
-                chan->drcmr = cfg->slave_id;
                 chan->dev_addr = addr;
+                /* FIXME: drivers should be ported over to use the filter
+                 * function. Once that's done, the following two lines can
+                 * be removed.
+                 */
+                if (cfg->slave_id)
+                        chan->drcmr = cfg->slave_id;
                 break;
         default:
                 return -ENOSYS;
@@ -877,6 +883,19 @@ static struct platform_driver mmp_pdma_driver = {
         .remove         = mmp_pdma_remove,
 };
 
+bool mmp_pdma_filter_fn(struct dma_chan *chan, void *param)
+{
+        struct mmp_pdma_chan *c = to_mmp_pdma_chan(chan);
+
+        if (chan->device->dev->driver != &mmp_pdma_driver.driver)
+                return false;
+
+        c->drcmr = *(unsigned int *) param;
+
+        return true;
+}
+EXPORT_SYMBOL_GPL(mmp_pdma_filter_fn);
+
 module_platform_driver(mmp_pdma_driver);
 
 MODULE_DESCRIPTION("MARVELL MMP Periphera DMA Driver");
diff --git a/include/linux/dma/mmp-pdma.h b/include/linux/dma/mmp-pdma.h
new file mode 100644
index 000000000000..2dc9b2bc18fc
--- /dev/null
+++ b/include/linux/dma/mmp-pdma.h
@@ -0,0 +1,15 @@
+#ifndef _MMP_PDMA_H_
+#define _MMP_PDMA_H_
+
+struct dma_chan;
+
+#ifdef CONFIG_MMP_PDMA
+bool mmp_pdma_filter_fn(struct dma_chan *chan, void *param);
+#else
+static inline bool mmp_pdma_filter_fn(struct dma_chan *chan, void *param)
+{
+        return false;
+}
+#endif
+
+#endif /* _MMP_PDMA_H_ */