Re: [PATCH 07/55] media: imx8-isi: Stop abusing of min_buffers_needed field

From: Laurent Pinchart
Date: Mon Nov 27 2023 - 12:07:26 EST


Hi Benjamin,

Thank you for the patch.

On Mon, Nov 27, 2023 at 05:54:06PM +0100, Benjamin Gaignard wrote:
> 'min_buffers_needed' is suppose to be used to indicate the number
> of buffers needed by DMA engine to start streaming.
> imx8-isi driver doesn't use DMA engine and just want to specify

What do you mean, "doesn't use DMA engine" ? The ISI surely has DMA
engines :-)

> 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@xxxxxxxxxxxxx>
> CC: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
> CC: Mauro Carvalho Chehab <mchehab@xxxxxxxxxx>
> CC: Shawn Guo <shawnguo@xxxxxxxxxx>
> CC: Sascha Hauer <s.hauer@xxxxxxxxxxxxxx>
> CC: Pengutronix Kernel Team <kernel@xxxxxxxxxxxxxx>
> CC: Fabio Estevam <festevam@xxxxxxxxx>
> CC: NXP Linux Team <linux-imx@xxxxxxx>
> ---
> drivers/media/platform/nxp/imx8-isi/imx8-isi-video.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/media/platform/nxp/imx8-isi/imx8-isi-video.c b/drivers/media/platform/nxp/imx8-isi/imx8-isi-video.c
> index 49bca2b01cc6..81673ff9084b 100644
> --- a/drivers/media/platform/nxp/imx8-isi/imx8-isi-video.c
> +++ b/drivers/media/platform/nxp/imx8-isi/imx8-isi-video.c
> @@ -1453,7 +1453,7 @@ int mxc_isi_video_register(struct mxc_isi_pipe *pipe,
> q->mem_ops = &vb2_dma_contig_memops;
> q->buf_struct_size = sizeof(struct mxc_isi_buffer);
> q->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC;
> - q->min_buffers_needed = 2;
> + q->min_reqbufs_allocation = 2;
> q->lock = &video->lock;
> q->dev = pipe->isi->dev;
>

--
Regards,

Laurent Pinchart