[PATCH v5 4/5] media: i2c: imx219: Increase minimum LLP to fix blocky artefacts

From: Jai Luthra
Date: Mon Dec 30 2024 - 01:12:56 EST


The sensor's internal ADC supports a minimum line length of 3448 pixels,
which may be too small to use with analog binning, where ADC operates on
two lines together. Switch to a higher minimum line length of 3560
pixels to fix the blocky artefacts seen with analog binning [1].

To keep the same default framerate as before for all the modes, lower
the default fll value to compensate for the increase in llp.

[1]: https://github.com/raspberrypi/rpicam-apps/issues/281#issuecomment-1082894118

Signed-off-by: Jai Luthra <jai.luthra@xxxxxxxxxxxxxxxx>
---
drivers/media/i2c/imx219.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/media/i2c/imx219.c b/drivers/media/i2c/imx219.c
index 9682a74feb3b7b74cd2ca54779323396c77cd5a5..5cbd7b90bed28bcf59debdba6dfc76bcd34eb9b4 100644
--- a/drivers/media/i2c/imx219.c
+++ b/drivers/media/i2c/imx219.c
@@ -74,7 +74,7 @@
#define IMX219_FLL_MAX 0xffff
#define IMX219_VBLANK_MIN 32
#define IMX219_REG_LINE_LENGTH CCI_REG16(0x0162)
-#define IMX219_LLP_MIN 0x0d78
+#define IMX219_LLP_MIN 0x0de8
#define IMX219_LLP_MAX 0x7ff0

#define IMX219_REG_X_ADD_STA_A CCI_REG16(0x0164)
@@ -287,25 +287,25 @@ static const struct imx219_mode supported_modes[] = {
/* 8MPix 15fps mode */
.width = 3280,
.height = 2464,
- .fll_def = 3526,
+ .fll_def = 3415,
},
{
/* 1080P 30fps cropped */
.width = 1920,
.height = 1080,
- .fll_def = 1763,
+ .fll_def = 1707,
},
{
/* 2x2 binned 30fps mode */
.width = 1640,
.height = 1232,
- .fll_def = 1763,
+ .fll_def = 1707,
},
{
/* 640x480 30fps mode */
.width = 640,
.height = 480,
- .fll_def = 1763,
+ .fll_def = 1707,
},
};


--
2.47.1