From: Nikhil Devshatwar <nikhil.nd@xxxxxx> 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 <nikhil.nd@xxxxxx> Signed-off-by: Benoit Parrot <bparrot@xxxxxx> --- drivers/media/platform/ti-vpe/vpdma.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/media/platform/ti-vpe/vpdma.c b/drivers/media/platform/ti-vpe/vpdma.c index 54c1174cad75..e8ed6bae83ed 100644 --- a/drivers/media/platform/ti-vpe/vpdma.c +++ b/drivers/media/platform/ti-vpe/vpdma.c @@ -367,7 +367,7 @@ int vpdma_map_desc_buf(struct vpdma_data *vpdma, struct vpdma_buf *buf) 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; @@ -388,7 +388,8 @@ void vpdma_unmap_desc_buf(struct vpdma_data *vpdma, struct vpdma_buf *buf) 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; } -- 2.9.0 -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html