[PATCH v5 05/14] media: mt9m114: Tweak default hblank and vblank for more accurate fps

Hans de Goede posted 14 patches 1 month, 1 week ago
[PATCH v5 05/14] media: mt9m114: Tweak default hblank and vblank for more accurate fps
Posted by Hans de Goede 1 month, 1 week ago
The PLL gets programmed to achieve a 48 MHz pixelclock, with the current
vblank + hblank defaults this results in a fps of:

48000000 / ((1296 + 307) * (976 + 23) = 29.974 fps

Tweak the defaults to get closer to 30 fps:

48000000 / ((1296 + 308) * (976 + 21) = 30.015 fps

This improves things from being 0.026 fps too low to 0.015 fps too high.

Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Hans de Goede <johannes.goede@oss.qualcomm.com>
---
 drivers/media/i2c/mt9m114.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/media/i2c/mt9m114.c b/drivers/media/i2c/mt9m114.c
index 3cb00e69623fa422bdecbe3eb36f911d92405341..b588b9d013ca8b41f9827cd12c0fcf56bb34bc38 100644
--- a/drivers/media/i2c/mt9m114.c
+++ b/drivers/media/i2c/mt9m114.c
@@ -337,8 +337,8 @@
  */
 #define MT9M114_MIN_HBLANK				303
 #define MT9M114_MIN_VBLANK				21
-#define MT9M114_DEF_HBLANK				307
-#define MT9M114_DEF_VBLANK				23
+#define MT9M114_DEF_HBLANK				308
+#define MT9M114_DEF_VBLANK				21
 
 #define MT9M114_DEF_FRAME_RATE				30
 #define MT9M114_MAX_FRAME_RATE				120

-- 
2.52.0