media: rockchip: rga: set dma mask to 32 bits

The RGA DMA descriptor list contains only 32-bit addresses. Set the
dma_mask to only allocate memory that is addressable by the descriptors.

This prevents errors when preparing vb2 buffers that were allocated by
the RGA.
Signed-off-by: Michael Tretter <m.tretter@pengutronix.de>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>

drivers/media/platform/rockchip/rga/rga.c

@@ -98,6 +98,7 @@ queue_init(void *priv, struct vb2_queue *src_vq, struct vb2_queue *dst_vq)
 	src_vq->drv_priv = ctx;
 	src_vq->ops = &rga_qops;
 	src_vq->mem_ops = &vb2_dma_sg_memops;
+	dst_vq->gfp_flags = __GFP_DMA32;
 	src_vq->buf_struct_size = sizeof(struct rga_vb_buffer);
 	src_vq->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_COPY;
 	src_vq->lock = &ctx->rga->mutex;
@@ -112,6 +113,7 @@ queue_init(void *priv, struct vb2_queue *src_vq, struct vb2_queue *dst_vq)
 	dst_vq->drv_priv = ctx;
 	dst_vq->ops = &rga_qops;
 	dst_vq->mem_ops = &vb2_dma_sg_memops;
+	dst_vq->gfp_flags = __GFP_DMA32;
 	dst_vq->buf_struct_size = sizeof(struct rga_vb_buffer);
 	dst_vq->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_COPY;
 	dst_vq->lock = &ctx->rga->mutex;
@@ -824,6 +826,12 @@ static int rga_probe(struct platform_device *pdev)
 		goto err_put_clk;
 	}
 
+	ret = dma_set_mask_and_coherent(rga->dev, DMA_BIT_MASK(32));
+	if (ret) {
+		dev_err(rga->dev, "32-bit DMA not supported");
+		goto err_put_clk;
+	}
+
 	ret = v4l2_device_register(&pdev->dev, &rga->v4l2_dev);
 	if (ret)
 		goto err_put_clk;