@@ -272,9 +272,14 @@ static int mt9v022_s_crop(struct v4l2_subdev *sd, struct v4l2_crop *a)
if (ret & 1) /* Autoexposure */
ret = reg_write(client, mt9v022->reg->max_total_shutter_width,
rect.height + mt9v022->y_skip_top + 43);
- else
- ret = reg_write(client, MT9V022_TOTAL_SHUTTER_WIDTH,
- rect.height + mt9v022->y_skip_top + 43);
+ /*
+ * If autoexposure is off, there is no need to set
+ * MT9V022_TOTAL_SHUTTER_WIDTH here. Autoexposure can be off
+ * only if the user has set exposure manually, using the
+ * V4L2_CID_EXPOSURE_AUTO with the value V4L2_EXPOSURE_MANUAL.
+ * In this case the register MT9V022_TOTAL_SHUTTER_WIDTH
+ * already contains the correct value.
+ */
}
/* Setup frame format: defaults apart from width and height */
if (!ret)
Since the MT9V022_TOTAL_SHUTTER_WIDTH register is controlled in manual mode by V4L2_CID_EXPOSURE control, it shouldn't be written directly in mt9v022_s_crop(). In manual mode this register should be set to the V4L2_CID_EXPOSURE control value. Changing this register directly and outside of the actual control function means that the register value is not in sync with the corresponding control value. Thus, the following problem is observed: - setting this control initially succeeds - VIDIOC_S_CROP ioctl() overwrites the MT9V022_TOTAL_SHUTTER_WIDTH register - setting this control to the same value again doesn't result in setting the register since the control value was previously cached and doesn't differ Remove MT9V022_TOTAL_SHUTTER_WIDTH register setting in mt9v022_s_crop() and add a comment explaining why it is not needed in manual mode. Signed-off-by: Anatolij Gustschin <agust@denx.de> --- Changes since first version: - remove setting total shutter width register in mt9v022_s_crop() if in manual exposure mode and add a comment explaining why it is not needed - revise commit log - rebase on staging/for_v3.7 branch drivers/media/i2c/soc_camera/mt9v022.c | 11 ++++++++--- 1 files changed, 8 insertions(+), 3 deletions(-)