Re: [PATCH] solo6x10: just pass frame motion flag from hardware, drop additional handling as complicated and unstable

From: Hans Verkuil
Date: Fri Dec 12 2014 - 08:31:12 EST


On 11/05/2014 09:11 PM, Andrey Utkin wrote:
> Dropping code (introduced in 316d9e84a72069e04e483de0d5934c1d75f6a44c)
> which intends to make raising of motion events more "smooth"(?).
>
> It made motion event never appear in my installation.
> That code is complicated, so I couldn't figure out quickly how to fix
> it, so dropping it seems better to me.
>
> Another justification is that anyway application would implement
> "motion signal stabilization" if required, it is not necessarily kernel
> driver's job.
>
> Signed-off-by: Andrey Utkin <andrey.utkin@xxxxxxxxxxxxxxxxxxx>

Acked-by: Hans Verkuil <hans.verkuil@xxxxxxxxx>

I have tested this and it looks good. I am not sure what problems I had
originally that caused me to write that code, since it is now functioning
as expected.

So you can expect this patch to be part of the next 3.20 pull request I'll
post.

Sorry for the delay.

Regards,

Hans

> ---
> drivers/media/pci/solo6x10/solo6x10-v4l2-enc.c | 30 +-------------------------
> drivers/media/pci/solo6x10/solo6x10.h | 2 --
> 2 files changed, 1 insertion(+), 31 deletions(-)
>
> diff --git a/drivers/media/pci/solo6x10/solo6x10-v4l2-enc.c b/drivers/media/pci/solo6x10/solo6x10-v4l2-enc.c
> index 30e09d9..866f7b3 100644
> --- a/drivers/media/pci/solo6x10/solo6x10-v4l2-enc.c
> +++ b/drivers/media/pci/solo6x10/solo6x10-v4l2-enc.c
> @@ -239,8 +239,6 @@ static int solo_enc_on(struct solo_enc_dev *solo_enc)
> if (solo_enc->bw_weight > solo_dev->enc_bw_remain)
> return -EBUSY;
> solo_enc->sequence = 0;
> - solo_enc->motion_last_state = false;
> - solo_enc->frames_since_last_motion = 0;
> solo_dev->enc_bw_remain -= solo_enc->bw_weight;
>
> if (solo_enc->type == SOLO_ENC_TYPE_EXT)
> @@ -555,36 +553,12 @@ static int solo_enc_fillbuf(struct solo_enc_dev *solo_enc,
> }
>
> if (!ret) {
> - bool send_event = false;
> -
> vb->v4l2_buf.sequence = solo_enc->sequence++;
> vb->v4l2_buf.timestamp.tv_sec = vop_sec(vh);
> vb->v4l2_buf.timestamp.tv_usec = vop_usec(vh);
>
> /* Check for motion flags */
> - if (solo_is_motion_on(solo_enc)) {
> - /* It takes a few frames for the hardware to detect
> - * motion. Once it does it clears the motion detection
> - * register and it takes again a few frames before
> - * motion is seen. This means in practice that when the
> - * motion field is 1, it will go back to 0 for the next
> - * frame. This leads to motion detection event being
> - * sent all the time, which is not what we want.
> - * Instead wait a few frames before deciding that the
> - * motion has halted. After some experimentation it
> - * turns out that waiting for 5 frames works well.
> - */
> - if (enc_buf->motion == 0 &&
> - solo_enc->motion_last_state &&
> - solo_enc->frames_since_last_motion++ > 5)
> - send_event = true;
> - else if (enc_buf->motion) {
> - solo_enc->frames_since_last_motion = 0;
> - send_event = !solo_enc->motion_last_state;
> - }
> - }
> -
> - if (send_event) {
> + if (solo_is_motion_on(solo_enc) && enc_buf->motion) {
> struct v4l2_event ev = {
> .type = V4L2_EVENT_MOTION_DET,
> .u.motion_det = {
> @@ -594,8 +568,6 @@ static int solo_enc_fillbuf(struct solo_enc_dev *solo_enc,
> },
> };
>
> - solo_enc->motion_last_state = enc_buf->motion;
> - solo_enc->frames_since_last_motion = 0;
> v4l2_event_queue(solo_enc->vfd, &ev);
> }
> }
> diff --git a/drivers/media/pci/solo6x10/solo6x10.h b/drivers/media/pci/solo6x10/solo6x10.h
> index 72017b7..dc503fd 100644
> --- a/drivers/media/pci/solo6x10/solo6x10.h
> +++ b/drivers/media/pci/solo6x10/solo6x10.h
> @@ -159,8 +159,6 @@ struct solo_enc_dev {
> u16 motion_thresh;
> bool motion_global;
> bool motion_enabled;
> - bool motion_last_state;
> - u8 frames_since_last_motion;
> u16 width;
> u16 height;
>
>

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