Re: [PATCH v7 27/49] media: pci: tw686x: Stop direct calls to queue num_buffers field

[Hans Verkuil]

On 14/09/2023 15:33, Benjamin Gaignard wrote:
> Use vb2_get_num_buffers() to avoid using queue num_buffer field directly.
> 
> Signed-off-by: Benjamin Gaignard <benjamin.gaignard@xxxxxxxxxxxxx>
> ---
>  drivers/media/pci/tw686x/tw686x-video.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/media/pci/tw686x/tw686x-video.c b/drivers/media/pci/tw686x/tw686x-video.c
> index 3ebf7a2c95f0..6bc6d143d18c 100644
> --- a/drivers/media/pci/tw686x/tw686x-video.c
> +++ b/drivers/media/pci/tw686x/tw686x-video.c
> @@ -423,6 +423,7 @@ static int tw686x_queue_setup(struct vb2_queue *vq,
>  			      unsigned int sizes[], struct device *alloc_devs[])
>  {
>  	struct tw686x_video_channel *vc = vb2_get_drv_priv(vq);
> +	unsigned int q_num_bufs = vb2_get_num_buffers(vq);
>  	unsigned int szimage =
>  		(vc->width * vc->height * vc->format->depth) >> 3;
>  
> @@ -430,8 +431,8 @@ static int tw686x_queue_setup(struct vb2_queue *vq,
>  	 * Let's request at least three buffers: two for the
>  	 * DMA engine and one for userspace.
>  	 */
> -	if (vq->num_buffers + *nbuffers < 3)
> -		*nbuffers = 3 - vq->num_buffers;
> +	if (q_num_bufs + *nbuffers < 3)
> +		*nbuffers = 3 - q_num_bufs;

Drop this check, and instead update min_buffers_needed from 2 to 3.

Regards,

	Hans

>  
>  	if (*nplanes) {
>  		if (*nplanes != 1 || sizes[0] < szimage)