| Message ID | 20211217095403.2618-5-jammy_huang@aspeedtech.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Correct timing report | expand |
On Fri, 17 Dec 2021 at 09:54, Jammy Huang <jammy_huang@aspeedtech.com> wrote: > > This is a workaround for polarity unstable. > Sync value get by VR09C counts from sync's rising edge, which means > sync's polarity is negative if sync value is bigger than total/2. > > Signed-off-by: Jammy Huang <jammy_huang@aspeedtech.com> > --- > drivers/media/platform/aspeed-video.c | 18 ++++++++++++++++++ > 1 file changed, 18 insertions(+) > > diff --git a/drivers/media/platform/aspeed-video.c b/drivers/media/platform/aspeed-video.c > index 5ad3a20c5bac..f628f69bb7dd 100644 > --- a/drivers/media/platform/aspeed-video.c > +++ b/drivers/media/platform/aspeed-video.c > @@ -989,6 +989,15 @@ static void aspeed_video_get_resolution(struct aspeed_video *video) > video->frame_top = FIELD_GET(VE_SRC_TB_EDGE_DET_TOP, > src_tb_edge); > det->vsync = FIELD_GET(VE_SYNC_STATUS_VSYNC, sync); > + /* > + * Workaround for polarity detection > + * Use sync(VR098) counts from sync's rising edge till falling > + * edge to tell sync polarity. > + */ > + if (det->vsync > (FIELD_GET(VE_MODE_DETECT_V_LINES, mds) >> 1)) Are you right shifting as this is the value / 2? I think it's clearer to write / 2 instead of >> 1. Mention in the comment that this is a workaround for when the sync value is larger than half. > + det->polarities &= ~V4L2_DV_VSYNC_POS_POL; > + else > + det->polarities |= V4L2_DV_VSYNC_POS_POL; > if (det->polarities & V4L2_DV_VSYNC_POS_POL) { > det->vbackporch = video->frame_top - det->vsync; > det->vfrontporch = > @@ -1010,6 +1019,15 @@ static void aspeed_video_get_resolution(struct aspeed_video *video) > video->frame_left = FIELD_GET(VE_SRC_LR_EDGE_DET_LEFT, > src_lr_edge); > det->hsync = FIELD_GET(VE_SYNC_STATUS_HSYNC, sync); > + /* > + * Workaround for polarity detection > + * Use sync(VR098) counts from sync's rising edge till falling > + * edge to tell sync polarity. > + */ > + if (det->hsync > (htotal >> 1)) > + det->polarities &= ~V4L2_DV_HSYNC_POS_POL; > + else > + det->polarities |= V4L2_DV_HSYNC_POS_POL; > if (det->polarities & V4L2_DV_HSYNC_POS_POL) { > det->hbackporch = video->frame_left - det->hsync; > det->hfrontporch = htotal - video->frame_right; > -- > 2.25.1 >
Hi Joel, OK, I will update in next patch as you advised. Thanks for your review. On 2021/12/22 上午 09:22, Joel Stanley wrote: > On Fri, 17 Dec 2021 at 09:54, Jammy Huang <jammy_huang@aspeedtech.com> wrote: >> This is a workaround for polarity unstable. >> Sync value get by VR09C counts from sync's rising edge, which means >> sync's polarity is negative if sync value is bigger than total/2. >> >> Signed-off-by: Jammy Huang <jammy_huang@aspeedtech.com> >> --- >> drivers/media/platform/aspeed-video.c | 18 ++++++++++++++++++ >> 1 file changed, 18 insertions(+) >> >> diff --git a/drivers/media/platform/aspeed-video.c b/drivers/media/platform/aspeed-video.c >> index 5ad3a20c5bac..f628f69bb7dd 100644 >> --- a/drivers/media/platform/aspeed-video.c >> +++ b/drivers/media/platform/aspeed-video.c >> @@ -989,6 +989,15 @@ static void aspeed_video_get_resolution(struct aspeed_video *video) >> video->frame_top = FIELD_GET(VE_SRC_TB_EDGE_DET_TOP, >> src_tb_edge); >> det->vsync = FIELD_GET(VE_SYNC_STATUS_VSYNC, sync); >> + /* >> + * Workaround for polarity detection >> + * Use sync(VR098) counts from sync's rising edge till falling >> + * edge to tell sync polarity. >> + */ >> + if (det->vsync > (FIELD_GET(VE_MODE_DETECT_V_LINES, mds) >> 1)) > Are you right shifting as this is the value / 2? I think it's clearer > to write / 2 instead of >> 1. > > Mention in the comment that this is a workaround for when the sync > value is larger than half. > >> + det->polarities &= ~V4L2_DV_VSYNC_POS_POL; >> + else >> + det->polarities |= V4L2_DV_VSYNC_POS_POL; >> if (det->polarities & V4L2_DV_VSYNC_POS_POL) { >> det->vbackporch = video->frame_top - det->vsync; >> det->vfrontporch = >> @@ -1010,6 +1019,15 @@ static void aspeed_video_get_resolution(struct aspeed_video *video) >> video->frame_left = FIELD_GET(VE_SRC_LR_EDGE_DET_LEFT, >> src_lr_edge); >> det->hsync = FIELD_GET(VE_SYNC_STATUS_HSYNC, sync); >> + /* >> + * Workaround for polarity detection >> + * Use sync(VR098) counts from sync's rising edge till falling >> + * edge to tell sync polarity. >> + */ >> + if (det->hsync > (htotal >> 1)) >> + det->polarities &= ~V4L2_DV_HSYNC_POS_POL; >> + else >> + det->polarities |= V4L2_DV_HSYNC_POS_POL; >> if (det->polarities & V4L2_DV_HSYNC_POS_POL) { >> det->hbackporch = video->frame_left - det->hsync; >> det->hfrontporch = htotal - video->frame_right; >> -- >> 2.25.1 >>
diff --git a/drivers/media/platform/aspeed-video.c b/drivers/media/platform/aspeed-video.c index 5ad3a20c5bac..f628f69bb7dd 100644 --- a/drivers/media/platform/aspeed-video.c +++ b/drivers/media/platform/aspeed-video.c @@ -989,6 +989,15 @@ static void aspeed_video_get_resolution(struct aspeed_video *video) video->frame_top = FIELD_GET(VE_SRC_TB_EDGE_DET_TOP, src_tb_edge); det->vsync = FIELD_GET(VE_SYNC_STATUS_VSYNC, sync); + /* + * Workaround for polarity detection + * Use sync(VR098) counts from sync's rising edge till falling + * edge to tell sync polarity. + */ + if (det->vsync > (FIELD_GET(VE_MODE_DETECT_V_LINES, mds) >> 1)) + det->polarities &= ~V4L2_DV_VSYNC_POS_POL; + else + det->polarities |= V4L2_DV_VSYNC_POS_POL; if (det->polarities & V4L2_DV_VSYNC_POS_POL) { det->vbackporch = video->frame_top - det->vsync; det->vfrontporch = @@ -1010,6 +1019,15 @@ static void aspeed_video_get_resolution(struct aspeed_video *video) video->frame_left = FIELD_GET(VE_SRC_LR_EDGE_DET_LEFT, src_lr_edge); det->hsync = FIELD_GET(VE_SYNC_STATUS_HSYNC, sync); + /* + * Workaround for polarity detection + * Use sync(VR098) counts from sync's rising edge till falling + * edge to tell sync polarity. + */ + if (det->hsync > (htotal >> 1)) + det->polarities &= ~V4L2_DV_HSYNC_POS_POL; + else + det->polarities |= V4L2_DV_HSYNC_POS_POL; if (det->polarities & V4L2_DV_HSYNC_POS_POL) { det->hbackporch = video->frame_left - det->hsync; det->hfrontporch = htotal - video->frame_right;
This is a workaround for polarity unstable. Sync value get by VR09C counts from sync's rising edge, which means sync's polarity is negative if sync value is bigger than total/2. Signed-off-by: Jammy Huang <jammy_huang@aspeedtech.com> --- drivers/media/platform/aspeed-video.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+)