media: mt9m114: Tweak default hblank and vblank for more accurate fps

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>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Hans Verkuil <hverkuil+cisco@kernel.org>

diff --git a/drivers/media/i2c/mt9m114.c b/drivers/media/i2c/mt9m114.c
index 0076723c5aa5bb82ab775f161bc9916c5126562d..a45e6709d1082e981d368fefb895ab8d5f5e27f9 100644 (file)
--- 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