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authorPhilipp Zabel <p.zabel@pengutronix.de>2015-05-04 07:51:06 -0300
committerMauro Carvalho Chehab <mchehab@osg.samsung.com>2015-05-12 03:53:06 -0300
commitc16218402a000bb25c1277c43ae98c11bcb59bd1 (patch)
treecccdee965d974306a2ad6e67aeb0cc0ae356bc40 /drivers/media/v4l2-core/v4l2-mem2mem.c
parentdc199241624a2fd85d9b0d8303babd60feadd0e6 (diff)
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[media] videobuf2: return -EPIPE from DQBUF after the last buffer
If the last buffer was dequeued from a capture queue, let poll return immediately and let DQBUF return -EPIPE to signal there will no more buffers to dequeue until STREAMOFF. The driver signals the last buffer by setting the V4L2_BUF_FLAG_LAST. To reenable dequeuing on the capture queue, the driver must explicitly call vb2_clear_last_buffer_queued. The last buffer queued flag is cleared automatically during STREAMOFF. Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de> Acked-by: Hans Verkuil <hans.verkuil@cisco.com> Signed-off-by: Kamil Debski <k.debski@samsung.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Diffstat (limited to 'drivers/media/v4l2-core/v4l2-mem2mem.c')
-rw-r--r--drivers/media/v4l2-core/v4l2-mem2mem.c10
1 files changed, 9 insertions, 1 deletions
diff --git a/drivers/media/v4l2-core/v4l2-mem2mem.c b/drivers/media/v4l2-core/v4l2-mem2mem.c
index 73824a5ada83..cbef15c07e53 100644
--- a/drivers/media/v4l2-core/v4l2-mem2mem.c
+++ b/drivers/media/v4l2-core/v4l2-mem2mem.c
@@ -564,8 +564,16 @@ unsigned int v4l2_m2m_poll(struct file *file, struct v4l2_m2m_ctx *m2m_ctx,
if (list_empty(&src_q->done_list))
poll_wait(file, &src_q->done_wq, wait);
- if (list_empty(&dst_q->done_list))
+ if (list_empty(&dst_q->done_list)) {
+ /*
+ * If the last buffer was dequeued from the capture queue,
+ * return immediately. DQBUF will return -EPIPE.
+ */
+ if (dst_q->last_buffer_dequeued)
+ return rc | POLLIN | POLLRDNORM;
+
poll_wait(file, &dst_q->done_wq, wait);
+ }
if (m2m_ctx->m2m_dev->m2m_ops->lock)
m2m_ctx->m2m_dev->m2m_ops->lock(m2m_ctx->priv);