media: i2c: ov9282: Correct the exposure offset

The datasheet lists that "Maximum exposure time is frame
length -25 row periods, where frame length is set by
registers {0x380E, 0x380F}".
However this driver had OV9282_EXPOSURE_OFFSET set to 12
which allowed that restriction to be violated, and would
result in very under-exposed images.

Correct the offset.

Fixes: 14ea315bbeb7 ("media: i2c: Add ov9282 camera sensor driver")
Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

diff --git a/drivers/media/i2c/ov9282.c b/drivers/media/i2c/ov9282.c
index 9f52af6f047f3c283eb0cdf8b90662cc37003255..87e5d7ce5a47ee23a721ea39c0ab314c6fca6007 100644 (file)
--- a/drivers/media/i2c/ov9282.c
+++ b/drivers/media/i2c/ov9282.c
@@ -40,7 +40,7 @@
 /* Exposure control */
 #define OV9282_REG_EXPOSURE    0x3500
 #define OV9282_EXPOSURE_MIN    1
-#define OV9282_EXPOSURE_OFFSET 12
+#define OV9282_EXPOSURE_OFFSET 25
 #define OV9282_EXPOSURE_STEP   1
 #define OV9282_EXPOSURE_DEFAULT        0x0282