[PATCH v2 2/2] media: rockchip: rkcif: comply with minimum number of buffers requirement

[Michael Riesch via B4 Relay]

From: Michael Riesch <michael.riesch@xxxxxxxxxxxxx>

Each stream requires CIF_REQ_BUFS_MIN=1 buffers to enable streaming.
However, it failed with only one buffer provided.

Comply with the minimum number of buffers requirement and accept
exactly one buffer.

Fixes: 501802e2ad51 ("media: rockchip: rkcif: add abstraction for dma blocks")
Cc: stable@xxxxxxxxxx
Tested-by: Paul Elder <paul.elder@xxxxxxxxxxxxxxxx>
Tested-by: Chen-Yu Tsai <wens@xxxxxxxxxx>
Signed-off-by: Michael Riesch <michael.riesch@xxxxxxxxxxxxx>
---
 .../media/platform/rockchip/rkcif/rkcif-stream.c   | 44 +++++++++++-----------
 1 file changed, 22 insertions(+), 22 deletions(-)

diff --git a/drivers/media/platform/rockchip/rkcif/rkcif-stream.c b/drivers/media/platform/rockchip/rkcif/rkcif-stream.c
index e00010a91e8b..f15bee4f7cd7 100644
--- a/drivers/media/platform/rockchip/rkcif/rkcif-stream.c
+++ b/drivers/media/platform/rockchip/rkcif/rkcif-stream.c
@@ -106,42 +106,42 @@ static int rkcif_stream_init_buffers(struct rkcif_stream *stream)
 {
 	struct v4l2_pix_format_mplane *pix = &stream->pix;
 
-	stream->buffers[0] = rkcif_stream_pop_buffer(stream);
-	if (!stream->buffers[0])
-		goto err_buff_0;
-
-	stream->buffers[1] = rkcif_stream_pop_buffer(stream);
-	if (!stream->buffers[1])
-		goto err_buff_1;
-
-	if (stream->queue_buffer) {
-		stream->queue_buffer(stream, 0);
-		stream->queue_buffer(stream, 1);
-	}
-
 	stream->dummy.size = pix->num_planes * pix->plane_fmt[0].sizeimage;
 	stream->dummy.vaddr =
 		dma_alloc_attrs(stream->rkcif->dev, stream->dummy.size,
 				&stream->dummy.buffer.buff_addr[0], GFP_KERNEL,
 				DMA_ATTR_NO_KERNEL_MAPPING);
 	if (!stream->dummy.vaddr)
-		goto err_dummy;
+		return -ENOMEM;
 
 	for (unsigned int i = 1; i < pix->num_planes; i++)
 		stream->dummy.buffer.buff_addr[i] =
 			stream->dummy.buffer.buff_addr[i - 1] +
 			pix->plane_fmt[i - 1].bytesperline * pix->height;
 
-	return 0;
+	stream->buffers[0] = rkcif_stream_pop_buffer(stream);
+	if (!stream->buffers[0])
+		goto err_dummy_free;
+
+	stream->buffers[1] = rkcif_stream_pop_buffer(stream);
+	if (!stream->buffers[1]) {
+		stream->buffers[1] = &stream->dummy.buffer;
+		stream->buffers[1]->is_dummy = true;
+	}
 
-err_dummy:
-	rkcif_stream_return_buffer(stream->buffers[1], VB2_BUF_STATE_QUEUED);
-	stream->buffers[1] = NULL;
+	if (stream->queue_buffer) {
+		stream->queue_buffer(stream, 0);
+		stream->queue_buffer(stream, 1);
+	}
+
+	return 0;
 
-err_buff_1:
-	rkcif_stream_return_buffer(stream->buffers[0], VB2_BUF_STATE_QUEUED);
-	stream->buffers[0] = NULL;
-err_buff_0:
+err_dummy_free:
+	dma_free_attrs(stream->rkcif->dev, stream->dummy.size,
+		       stream->dummy.vaddr,
+		       stream->dummy.buffer.buff_addr[0],
+		       DMA_ATTR_NO_KERNEL_MAPPING);
+	stream->dummy.vaddr = NULL;
 	return -EINVAL;
 }
 

-- 
2.39.5