VPDMA buffer will be used by CPU as well as by the VPDMA.
CPU will write/update the VPDMA descriptors containing data
about the video buffer DMA addresses.
VPDMA will write the "write descriptor" containing the
data about the DMA operation.
When mapping/unmapping the buffer, driver has to take care of
WriteBack and invalidation of the cache so that all the
coherency is maintained from both directions.
Use DMA_BIDIRECTIONAL to maintain coherency between CPU and VPDMA.
Signed-off-by: Nikhil Devshatwar <[email protected]>
Signed-off-by: Benoit Parrot <[email protected]>
Signed-off-by: Hans Verkuil <[email protected]>
Signed-off-by: Mauro Carvalho Chehab <[email protected]>
WARN_ON(buf->mapped);
buf->dma_addr = dma_map_single(dev, buf->addr, buf->size,
- DMA_TO_DEVICE);
+ DMA_BIDIRECTIONAL);
if (dma_mapping_error(dev, buf->dma_addr)) {
dev_err(dev, "failed to map buffer\n");
return -EINVAL;
struct device *dev = &vpdma->pdev->dev;
if (buf->mapped)
- dma_unmap_single(dev, buf->dma_addr, buf->size, DMA_TO_DEVICE);
+ dma_unmap_single(dev, buf->dma_addr, buf->size,
+ DMA_BIDIRECTIONAL);
buf->mapped = false;
}