Hi Thierry, On Mon, Oct 24, 2016 at 09:30:21AM +0200, Thierry Escande wrote: ... > --- a/include/media/videobuf2-core.h > +++ b/include/media/videobuf2-core.h > @@ -433,6 +433,9 @@ struct vb2_buf_ops { > * @quirk_poll_must_check_waiting_for_buffers: Return POLLERR at poll when QBUF > * has not been called. This is a vb1 idiom that has been adopted > * also by vb2. > + * @capture_dma_bidirectional: use DMA_BIDIRECTIONAL for CAPTURE buffers; this > + * allows HW to read from the CAPTURE buffers in > + * addition to writing; ignored for OUTPUT queues. > * @lock: pointer to a mutex that protects the vb2_queue struct. The > * driver can set this to a mutex to let the v4l2 core serialize > * the queuing ioctls. If the driver wants to handle locking > @@ -499,6 +502,7 @@ struct vb2_queue { > unsigned fileio_write_immediately:1; > unsigned allow_zero_bytesused:1; > unsigned quirk_poll_must_check_waiting_for_buffers:1; > + unsigned capture_dma_bidirectional:1; > > struct mutex *lock; > void *owner; > @@ -554,6 +558,26 @@ struct vb2_queue { > #endif > }; > > +/* > + * Returns the corresponding DMA direction given the vb2_queue type (capture or > + * output). Returns DMA_BIDIRECTIONAL for capture buffers if the vb2_queue field > + * capture_dma_bidirectional is set by the driver. > + */ > +#define VB2_DMA_DIR(q) (V4L2_TYPE_IS_OUTPUT((q)->type) \ q->is_output is assigned in vb2_queue_init(): q->is_output = V4L2_TYPE_IS_OUTPUT(q->type); Could you use that instead? With that changed, Acked-by: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx> > + ? DMA_TO_DEVICE \ > + : (q)->capture_dma_bidirectional \ > + ? DMA_BIDIRECTIONAL \ > + : DMA_FROM_DEVICE) > + > +/* > + * Returns true if the DMA direction passed as parameter refers to a capture > + * buffer as capture buffers allow both FROM_DEVICE and BIDIRECTIONAL DMA > + * direction. This test is used to map virtual addresses for writing and to mark > + * pages as dirty. > + */ > +#define VB2_DMA_DIR_CAPTURE(d) \ > + ((d) == DMA_FROM_DEVICE || (d) == DMA_BIDIRECTIONAL) > + > /** > * vb2_plane_vaddr() - Return a kernel virtual address of a given plane > * @vb: vb2_buffer to which the plane in question belongs to -- Kind regards, Sakari Ailus e-mail: sakari.ailus@xxxxxx XMPP: sailus@xxxxxxxxxxxxxx -- 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