dmaengine: sf-pdma: Support of_dma_controller_register()

Update sf-pdma driver to adopt generic DMA device tree bindings.
It calls of_dma_controller_register() with of_dma_xlate_by_chan_id
to get the generic DMA device tree helper support and the DMA
clients can look up the sf-pdma controller using standard APIs.

Signed-off-by: Shravan Chippa <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Vinod Koul <[e-mail]>

drivers/dma/sf-pdma/sf-pdma.c

···
 #include <linux/mod_devicetable.h>
 #include <linux/dma-mapping.h>
 #include <linux/of.h>
+#include <linux/of_dma.h>
 #include <linux/slab.h>
 
 #include "sf-pdma.h"
···
 		return ret;
 	}
 
+	ret = of_dma_controller_register(pdev->dev.of_node,
+					 of_dma_xlate_by_chan_id, pdma);
+	if (ret < 0) {
+		dev_err(&pdev->dev,
+			"Can't register SiFive Platform OF_DMA. (%d)\n", ret);
+		goto err_unregister;
+	}
+
 	return 0;
+
+err_unregister:
+	dma_async_device_unregister(&pdma->dma_dev);
+
+	return ret;
 }
 
 static void sf_pdma_remove(struct platform_device *pdev)
···
 		tasklet_kill(&ch->done_tasklet);
 		tasklet_kill(&ch->err_tasklet);
 	}
+
+	if (pdev->dev.of_node)
+		of_dma_controller_free(pdev->dev.of_node);
 
 	dma_async_device_unregister(&pdma->dma_dev);
 }