[media] videobuf2-dma-contig: make cookie() return a pointer to dma_addr_t

dma_addr_t may not fit into void* on some architectures. To be safe, make
vb2_dma_contig_cookie() return a pointer to dma_addr_t and dereference it
in vb2_dma_contig_plane_paddr() back to dma_addr_t.
Signed-off-by: Pawel Osciak <pawel@osciak.com>
Reported-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/video/videobuf2-dma-contig.c

@@ -78,7 +78,7 @@ static void *vb2_dma_contig_cookie(void *buf_priv)
 {
 	struct vb2_dc_buf *buf = buf_priv;
 
-	return (void *)buf->paddr;
+	return &buf->paddr;
 }
 
 static void *vb2_dma_contig_vaddr(void *buf_priv)

include/media/videobuf2-dma-contig.h

@@ -14,11 +14,14 @@
 #define _MEDIA_VIDEOBUF2_DMA_COHERENT_H
 
 #include <media/videobuf2-core.h>
+#include <linux/dma-mapping.h>
 
-static inline unsigned long vb2_dma_contig_plane_paddr(
-		struct vb2_buffer *vb, unsigned int plane_no)
+static inline dma_addr_t
+vb2_dma_contig_plane_paddr(struct vb2_buffer *vb, unsigned int plane_no)
 {
-	return (unsigned long)vb2_plane_cookie(vb, plane_no);
+	dma_addr_t *paddr = vb2_plane_cookie(vb, plane_no);
+
+	return *paddr;
 }
 
 void *vb2_dma_contig_init_ctx(struct device *dev);