On Fri, 17 Dec 2021 at 09:54, Jammy Huang <jammy_huang@xxxxxxxxxxxxxx> wrote:
>
> Correct timing's fp/sync/bp value based on the information below.
> It should be noticed that the calculation formula should be changed
> per sync polarity.
>
> The sequence of signal: sync - backporch - video data - frontporch
>
> The following registers start counting from sync's rising edge:
> 1. VR090: frame edge's left and right
> 2. VR094: frame edge's top and bottom
> 3. VR09C: counting from sync's rising edge to falling edge
>
> +--+ +-------------------+ +--+
> | | | v i d e o | | |
> +--+ +-----+ +-----+ +---+
>
> sync+--+
> left/top+--------+
> right/bottom+----------------------------+
>
> +-------------------+
> | v i d e o |
> +--+ +-----+ +-----+ +---+
> | | | |
> +--+ +--+
> sync+-------------------------------+
> left/top+-----+
> right/bottom+-------------------------+
This is a good explanation. Can you add detail that relates the names
you use here to to the variable names in your patch (or change them to
match)?
>
> Signed-off-by: Jammy Huang <jammy_huang@xxxxxxxxxxxxxx>
> ---
> drivers/media/platform/aspeed-video.c | 27 ++++++++++++++++++++++-----
> 1 file changed, 22 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/media/platform/aspeed-video.c b/drivers/media/platform/aspeed-video.c
> index 581a4261f9b7..5ad3a20c5bac 100644
> --- a/drivers/media/platform/aspeed-video.c
> +++ b/drivers/media/platform/aspeed-video.c
> @@ -988,10 +988,20 @@ static void aspeed_video_get_resolution(struct aspeed_video *video)
> src_tb_edge);
> video->frame_top = FIELD_GET(VE_SRC_TB_EDGE_DET_TOP,
> src_tb_edge);
> - det->vfrontporch = video->frame_top;
> - det->vbackporch = FIELD_GET(VE_MODE_DETECT_V_LINES, mds) -
> - video->frame_bottom;
> det->vsync = FIELD_GET(VE_SYNC_STATUS_VSYNC, sync);
Would it be clearer if you structured the code like this?
vsync = FIELD_GET(VE_SYNC_STATUS_VSYNC, sync);
vlines = FIELD_GET(VE_MODE_DETECT_V_LINES, mds);
if (det->polarities & V4L2_DV_VSYNC_POS_POL)) {
det->vbackporch = video->frame_top - vsync;
det->vfrontporch = vlines - video->frame_bottom;
det->vsync = vsync;
} else {
det->vbackporch = video->frame_top;
det->vfrontporch = vlines - video->frame_bottom - vsync;
det->vsync = vlines - vsync;
}
> + if (det->polarities & V4L2_DV_VSYNC_POS_POL) {
> + det->vbackporch = video->frame_top - det->vsync;
> + det->vfrontporch =
> + FIELD_GET(VE_MODE_DETECT_V_LINES, mds) -
> + video->frame_bottom;
> + } else {
> + det->vsync = FIELD_GET(VE_MODE_DETECT_V_LINES, mds) -
> + det->vsync;
> + det->vbackporch = video->frame_top;
> + det->vfrontporch =
> + FIELD_GET(VE_MODE_DETECT_V_LINES, mds) -
> + video->frame_bottom - det->vsync;
> + }
> if (video->frame_top > video->frame_bottom)
> continue;
>
> @@ -999,9 +1009,16 @@ static void aspeed_video_get_resolution(struct aspeed_video *video)
> src_lr_edge);
> video->frame_left = FIELD_GET(VE_SRC_LR_EDGE_DET_LEFT,
> src_lr_edge);
> - det->hfrontporch = video->frame_left;
> - det->hbackporch = htotal - video->frame_right;
> det->hsync = FIELD_GET(VE_SYNC_STATUS_HSYNC, sync);
> + if (det->polarities & V4L2_DV_HSYNC_POS_POL) {
> + det->hbackporch = video->frame_left - det->hsync;
> + det->hfrontporch = htotal - video->frame_right;
> + } else {
> + det->hsync = htotal - det->hsync;
> + det->hbackporch = video->frame_left;
> + det->hfrontporch = htotal - video->frame_right -
> + det->hsync;
> + }
> if (video->frame_left > video->frame_right)
> continue;
>
> --
> 2.25.1
>
