| Message ID | 20231127165454.166373-28-benjamin.gaignard@collabora.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Clean up queue_setup()/min_buffers_needed (ab)use | expand |
Hi Benjamin, On Mon 27 Nov 23, 17:54, Benjamin Gaignard wrote: > 'min_buffers_needed' is suppose to be used to indicate the number > of buffers needed by DMA engine to start streaming. > sun6i-isp driver doesn't use DMA engine and just want to specify > the minimum number of buffers to allocate when calling VIDIOC_REQBUFS. > That 'min_reqbufs_allocation' field purpose so use it. The hardware actually has its own DMA engine. It can work with just one buffer though (which will never be returned to userspace). But I think we should still require at least two buffers allocated, otherwise the driver will be of no use at all. So I don't think the commit message here is correct. Cheers, Paul > Signed-off-by: Benjamin Gaignard <benjamin.gaignard@collabora.com> > CC: Paul Kocialkowski <paul.kocialkowski@bootlin.com> > CC: Chen-Yu Tsai <wens@csie.org> > CC: Jernej Skrabec <jernej.skrabec@gmail.com> > CC: Samuel Holland <samuel@sholland.org> > CC: linux-sunxi@lists.linux.dev > --- > drivers/staging/media/sunxi/sun6i-isp/sun6i_isp_capture.c | 2 +- > drivers/staging/media/sunxi/sun6i-isp/sun6i_isp_params.c | 2 +- > 2 files changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/staging/media/sunxi/sun6i-isp/sun6i_isp_capture.c b/drivers/staging/media/sunxi/sun6i-isp/sun6i_isp_capture.c > index 1595a9607775..f47f9946c19f 100644 > --- a/drivers/staging/media/sunxi/sun6i-isp/sun6i_isp_capture.c > +++ b/drivers/staging/media/sunxi/sun6i-isp/sun6i_isp_capture.c > @@ -660,7 +660,7 @@ int sun6i_isp_capture_setup(struct sun6i_isp_device *isp_dev) > queue->buf_struct_size = sizeof(struct sun6i_isp_buffer); > queue->ops = &sun6i_isp_capture_queue_ops; > queue->mem_ops = &vb2_dma_contig_memops; > - queue->min_buffers_needed = 2; > + queue->min_reqbufs_allocation = 2; > queue->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC; > queue->lock = &capture->lock; > queue->dev = isp_dev->dev; > diff --git a/drivers/staging/media/sunxi/sun6i-isp/sun6i_isp_params.c b/drivers/staging/media/sunxi/sun6i-isp/sun6i_isp_params.c > index e28be895b486..259f6bfcb620 100644 > --- a/drivers/staging/media/sunxi/sun6i-isp/sun6i_isp_params.c > +++ b/drivers/staging/media/sunxi/sun6i-isp/sun6i_isp_params.c > @@ -489,7 +489,7 @@ int sun6i_isp_params_setup(struct sun6i_isp_device *isp_dev) > queue->buf_struct_size = sizeof(struct sun6i_isp_buffer); > queue->ops = &sun6i_isp_params_queue_ops; > queue->mem_ops = &vb2_vmalloc_memops; > - queue->min_buffers_needed = 1; > + queue->min_reqbufs_allocation = 1; > queue->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC; > queue->lock = ¶ms->lock; > queue->dev = isp_dev->dev; > -- > 2.39.2 >
Le 29/11/2023 à 14:40, Paul Kocialkowski a écrit : > Hi Benjamin, > > On Mon 27 Nov 23, 17:54, Benjamin Gaignard wrote: >> 'min_buffers_needed' is suppose to be used to indicate the number >> of buffers needed by DMA engine to start streaming. >> sun6i-isp driver doesn't use DMA engine and just want to specify >> the minimum number of buffers to allocate when calling VIDIOC_REQBUFS. >> That 'min_reqbufs_allocation' field purpose so use it. > The hardware actually has its own DMA engine. It can work with just one buffer > though (which will never be returned to userspace). But I think we should still > require at least two buffers allocated, otherwise the driver will be of no use > at all. > > So I don't think the commit message here is correct. That is exactly the info I hope to get for this first series since I don't know each hardware block details. I will remove this commit and make the driver use min_queued_buffers field instead so that will fit with it needs. Thanks, Benjamin > > Cheers, > > Paul > >> Signed-off-by: Benjamin Gaignard <benjamin.gaignard@collabora.com> >> CC: Paul Kocialkowski <paul.kocialkowski@bootlin.com> >> CC: Chen-Yu Tsai <wens@csie.org> >> CC: Jernej Skrabec <jernej.skrabec@gmail.com> >> CC: Samuel Holland <samuel@sholland.org> >> CC: linux-sunxi@lists.linux.dev >> --- >> drivers/staging/media/sunxi/sun6i-isp/sun6i_isp_capture.c | 2 +- >> drivers/staging/media/sunxi/sun6i-isp/sun6i_isp_params.c | 2 +- >> 2 files changed, 2 insertions(+), 2 deletions(-) >> >> diff --git a/drivers/staging/media/sunxi/sun6i-isp/sun6i_isp_capture.c b/drivers/staging/media/sunxi/sun6i-isp/sun6i_isp_capture.c >> index 1595a9607775..f47f9946c19f 100644 >> --- a/drivers/staging/media/sunxi/sun6i-isp/sun6i_isp_capture.c >> +++ b/drivers/staging/media/sunxi/sun6i-isp/sun6i_isp_capture.c >> @@ -660,7 +660,7 @@ int sun6i_isp_capture_setup(struct sun6i_isp_device *isp_dev) >> queue->buf_struct_size = sizeof(struct sun6i_isp_buffer); >> queue->ops = &sun6i_isp_capture_queue_ops; >> queue->mem_ops = &vb2_dma_contig_memops; >> - queue->min_buffers_needed = 2; >> + queue->min_reqbufs_allocation = 2; >> queue->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC; >> queue->lock = &capture->lock; >> queue->dev = isp_dev->dev; >> diff --git a/drivers/staging/media/sunxi/sun6i-isp/sun6i_isp_params.c b/drivers/staging/media/sunxi/sun6i-isp/sun6i_isp_params.c >> index e28be895b486..259f6bfcb620 100644 >> --- a/drivers/staging/media/sunxi/sun6i-isp/sun6i_isp_params.c >> +++ b/drivers/staging/media/sunxi/sun6i-isp/sun6i_isp_params.c >> @@ -489,7 +489,7 @@ int sun6i_isp_params_setup(struct sun6i_isp_device *isp_dev) >> queue->buf_struct_size = sizeof(struct sun6i_isp_buffer); >> queue->ops = &sun6i_isp_params_queue_ops; >> queue->mem_ops = &vb2_vmalloc_memops; >> - queue->min_buffers_needed = 1; >> + queue->min_reqbufs_allocation = 1; >> queue->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC; >> queue->lock = ¶ms->lock; >> queue->dev = isp_dev->dev; >> -- >> 2.39.2 >>
diff --git a/drivers/staging/media/sunxi/sun6i-isp/sun6i_isp_capture.c b/drivers/staging/media/sunxi/sun6i-isp/sun6i_isp_capture.c index 1595a9607775..f47f9946c19f 100644 --- a/drivers/staging/media/sunxi/sun6i-isp/sun6i_isp_capture.c +++ b/drivers/staging/media/sunxi/sun6i-isp/sun6i_isp_capture.c @@ -660,7 +660,7 @@ int sun6i_isp_capture_setup(struct sun6i_isp_device *isp_dev) queue->buf_struct_size = sizeof(struct sun6i_isp_buffer); queue->ops = &sun6i_isp_capture_queue_ops; queue->mem_ops = &vb2_dma_contig_memops; - queue->min_buffers_needed = 2; + queue->min_reqbufs_allocation = 2; queue->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC; queue->lock = &capture->lock; queue->dev = isp_dev->dev; diff --git a/drivers/staging/media/sunxi/sun6i-isp/sun6i_isp_params.c b/drivers/staging/media/sunxi/sun6i-isp/sun6i_isp_params.c index e28be895b486..259f6bfcb620 100644 --- a/drivers/staging/media/sunxi/sun6i-isp/sun6i_isp_params.c +++ b/drivers/staging/media/sunxi/sun6i-isp/sun6i_isp_params.c @@ -489,7 +489,7 @@ int sun6i_isp_params_setup(struct sun6i_isp_device *isp_dev) queue->buf_struct_size = sizeof(struct sun6i_isp_buffer); queue->ops = &sun6i_isp_params_queue_ops; queue->mem_ops = &vb2_vmalloc_memops; - queue->min_buffers_needed = 1; + queue->min_reqbufs_allocation = 1; queue->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC; queue->lock = ¶ms->lock; queue->dev = isp_dev->dev;
'min_buffers_needed' is suppose to be used to indicate the number of buffers needed by DMA engine to start streaming. sun6i-isp driver doesn't use DMA engine and just want to specify the minimum number of buffers to allocate when calling VIDIOC_REQBUFS. That 'min_reqbufs_allocation' field purpose so use it. Signed-off-by: Benjamin Gaignard <benjamin.gaignard@collabora.com> CC: Paul Kocialkowski <paul.kocialkowski@bootlin.com> CC: Chen-Yu Tsai <wens@csie.org> CC: Jernej Skrabec <jernej.skrabec@gmail.com> CC: Samuel Holland <samuel@sholland.org> CC: linux-sunxi@lists.linux.dev --- drivers/staging/media/sunxi/sun6i-isp/sun6i_isp_capture.c | 2 +- drivers/staging/media/sunxi/sun6i-isp/sun6i_isp_params.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-)