[PATCH v2 3/4] media: aspeed: Correct values for detected timing
From: Jammy Huang <hidden>
Date: 2021-12-22 08:21:54
Also in:
linux-arm-kernel, linux-media, lkml, openbmc
Subsystem:
media input infrastructure (v4l/dvb), the rest · Maintainers:
Mauro Carvalho Chehab, Linus Torvalds
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
[Vertical timing]
+--+ +-------------------+ +--+
| | | v i d e o | | |
+--+ +-----+ +-----+ +---+
vsync+--+
frame_top+--------+
frame_bottom+----------------------------+
+-------------------+
| v i d e o |
+--+ +-----+ +-----+ +---+
| | | |
+--+ +--+
vsync+-------------------------------+
frame_top+-----+
frame_bottom+-------------------------+
[Horizontal timing]
+--+ +-------------------+ +--+
| | | v i d e o | | |
+--+ +-----+ +-----+ +---+
hsync+--+
frame_left+--------+
frame_right+----------------------------+
+-------------------+
| v i d e o |
+--+ +-----+ +-----+ +---+
| | | |
+--+ +--+
hsync+-------------------------------+
frame_left+-----+
frame_right+-------------------------+
Signed-off-by: Jammy Huang <redacted>
---
v2:
- Code refined per Joel's suggestion
- Update commit message to have name matching variable
---
drivers/media/platform/aspeed-video.c | 30 ++++++++++++++++++++-------
1 file changed, 22 insertions(+), 8 deletions(-)
diff --git a/drivers/media/platform/aspeed-video.c b/drivers/media/platform/aspeed-video.c
index c241038ee27c..7c50567f5ab0 100644
--- a/drivers/media/platform/aspeed-video.c
+++ b/drivers/media/platform/aspeed-video.c@@ -936,7 +936,7 @@ static void aspeed_video_get_resolution(struct aspeed_video *video) u32 src_lr_edge; u32 src_tb_edge; u32 sync; - u32 htotal; + u32 htotal, vtotal, vsync, hsync; struct v4l2_bt_timings *det = &video->detected_timings; det->width = MIN_WIDTH;
@@ -983,21 +983,35 @@ static void aspeed_video_get_resolution(struct aspeed_video *video) mds = aspeed_video_read(video, VE_MODE_DETECT_STATUS); sync = aspeed_video_read(video, VE_SYNC_STATUS); htotal = aspeed_video_read(video, VE_H_TOTAL_PIXELS); + vtotal = FIELD_GET(VE_MODE_DETECT_V_LINES, mds); + vsync = FIELD_GET(VE_SYNC_STATUS_VSYNC, sync); + hsync = FIELD_GET(VE_SYNC_STATUS_HSYNC, sync); video->frame_bottom = FIELD_GET(VE_SRC_TB_EDGE_DET_BOT, 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); + if (det->polarities & V4L2_DV_VSYNC_POS_POL) { + det->vbackporch = video->frame_top - vsync; + det->vfrontporch = vtotal - video->frame_bottom; + det->vsync = vsync; + } else { + det->vbackporch = video->frame_top; + det->vfrontporch = vsync - video->frame_bottom; + det->vsync = vtotal - vsync; + } if (video->frame_top > video->frame_bottom) continue; video->frame_right = FIELD_GET(VE_SRC_LR_EDGE_DET_RT, 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 - hsync; + det->hfrontporch = htotal - video->frame_right; + det->hsync = hsync; + } else { + det->hbackporch = video->frame_left; + det->hfrontporch = hsync - video->frame_right; + det->hsync = htotal - hsync; + } if (video->frame_left > video->frame_right) continue;
--
2.25.1