Hi Laurent
On Thu, Feb 03, 2022 at 12:29:47AM +0200, Laurent Pinchart wrote:
> Hi Jacopo,
>
> Thank you for the patch.
>
> On Mon, Jan 31, 2022 at 03:44:42PM +0100, Jacopo Mondi wrote:
> > Implement the get_selection pad operation for the OV5640 sensor driver.
> >
> > The supported targets report the sensor's native size, the active pixel
> > array size and the analog crop rectangle from which the image is
> > produced.
> >
> > Signed-off-by: Jacopo Mondi <jacopo@xxxxxxxxxx>
> > ---
> > drivers/media/i2c/ov5640.c | 61 ++++++++++++++++++++++++++++++++++++++
> > 1 file changed, 61 insertions(+)
> >
> > diff --git a/drivers/media/i2c/ov5640.c b/drivers/media/i2c/ov5640.c
> > index 762bdca83aec..ae22300b9655 100644
> > --- a/drivers/media/i2c/ov5640.c
> > +++ b/drivers/media/i2c/ov5640.c
> > @@ -35,6 +35,13 @@
> > #define OV5640_MIN_VBLANK 24
> > #define OV5640_MAX_VTS 1968
> >
> > +#define OV5640_NATIVE_WIDTH 2624
> > +#define OV5640_NATIVE_HEIGHT 1964
> > +#define OV5640_PIXEL_ARRAY_TOP 8
> > +#define OV5640_PIXEL_ARRAY_LEFT 16
> > +#define OV5640_PIXEL_ARRAY_WIDTH 2592
> > +#define OV5640_PIXEL_ARRAY_HEIGHT 1944
>
> According to the datasheet, the sensor has 8 black lines, 6 dummy lines,
> 1944 active lines and 6 dummy lines. Horizontally, it has 16 dummy
> columns, 2592 active columns, and 16 dummy columns. If "pixel array" is
> meant to refer to the active area (I dislike the "active" name here, as
> the dummy lines and columns are typically "active" too, but that's a
> digression), then top should be 14.
>
Corret, I have only considered the 8 black lines, but dummy too are
'active but not valid' ones.
I'll change to 14
> > +
> > #define OV5640_DEFAULT_SLAVE_ID 0x3c
> >
> > #define OV5640_REG_SYS_RESET02 0x3002
> > @@ -2667,6 +2674,52 @@ static int ov5640_set_fmt(struct v4l2_subdev *sd,
> > return ret;
> > }
> >
> > +static int ov5640_get_selection(struct v4l2_subdev *sd,
> > + struct v4l2_subdev_state *sd_state,
> > + struct v4l2_subdev_selection *sel)
> > +{
> > + struct ov5640_dev *sensor = to_ov5640_dev(sd);
> > + const struct ov5640_mode_info *mode = sensor->current_mode;
> > + const struct v4l2_rect *analog_crop = &mode->analog_crop;
> > + const struct v4l2_rect *crop = &mode->crop;
> > +
> > + switch (sel->target) {
> > + case V4L2_SEL_TGT_CROP: {
> > + mutex_lock(&sensor->lock);
> > +
> > + sel->r.top = analog_crop->top + OV5640_PIXEL_ARRAY_TOP;
> > + sel->r.left = analog_crop->left + OV5640_PIXEL_ARRAY_LEFT;
> > + sel->r.width = analog_crop->width
> > + - analog_crop->left - crop->left;
>
> Why do you subtract the left coordinates here ?
>
As the analog_crop->width is defined from the full pixel array size
(black + dummy + active). The TGT_CROP rectangle width and height
should instead report the dimensions of the portion of the pixel array
size which is processed to obtain the final image, and thus the
vertical and horizontal offsets should be subtracted
full analog_crop.width
| (0x3804, 0x3805) = 2624
| |
V V
-> +-----------------------------------+
| |
x-----------------------------------|
| x---- TGT_CROP width ----------|
| | |
| | |
| | |
| | |
| | |
| | |
| | |
+--|--------------------------------+
| |
| |-> crop.left = 16
|
|-> analog_crop.left = 0
> > + sel->r.height = analog_crop->height
> > + - analog_crop->top - crop->top;
> > +
> > + mutex_unlock(&sensor->lock);
> > +
> > + return 0;
> > + }
> > +
> > + case V4L2_SEL_TGT_NATIVE_SIZE:
> > + sel->r.top = 0;
> > + sel->r.left = 0;
> > + sel->r.width = OV5640_NATIVE_WIDTH;
> > + sel->r.height = OV5640_NATIVE_HEIGHT;
> > +
> > + return 0;
> > +
> > + case V4L2_SEL_TGT_CROP_DEFAULT:
> > + case V4L2_SEL_TGT_CROP_BOUNDS:
> > + sel->r.top = OV5640_PIXEL_ARRAY_TOP;
> > + sel->r.left = OV5640_PIXEL_ARRAY_LEFT;
> > + sel->r.width = OV5640_PIXEL_ARRAY_WIDTH;
> > + sel->r.height = OV5640_PIXEL_ARRAY_HEIGHT;
>
> In libcamera we use V4L2_SEL_TGT_CROP_BOUNDS to set PixelArraySize,
> ignoring the left and top coordinates, and V4L2_SEL_TGT_CROP_DEFAULT to
> to set the PixelArrayActiveAreas property relative to PixelArraySize.
> This means that non-zero values for the left and top coordinates of
> V4L2_SEL_TGT_CROP_BOUNDS will cause issues. Is this an issue in
> libcamera, or should V4L2_SEL_TGT_CROP_BOUNDS be changed here ?
>
> The related question is, can we read the optical black lines and the
> dummy lines and columns ?
>
> > +
> > + return 0;
> > + }
> > +
> > + return -EINVAL;
> > +}
> > +
> > static int ov5640_set_framefmt(struct ov5640_dev *sensor,
> > struct v4l2_mbus_framefmt *format)
> > {
> > @@ -3369,6 +3422,7 @@ static const struct v4l2_subdev_pad_ops ov5640_pad_ops = {
> > .enum_mbus_code = ov5640_enum_mbus_code,
> > .get_fmt = ov5640_get_fmt,
> > .set_fmt = ov5640_set_fmt,
> > + .get_selection = ov5640_get_selection,
> > .enum_frame_size = ov5640_enum_frame_size,
> > .enum_frame_interval = ov5640_enum_frame_interval,
> > };
> > @@ -3383,9 +3437,16 @@ static int ov5640_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
> > {
> > struct v4l2_mbus_framefmt *try_fmt =
> > v4l2_subdev_get_try_format(sd, fh->state, 0);
> > + struct v4l2_rect *try_crop =
> > + v4l2_subdev_get_try_crop(sd, fh->state, 0);
> >
> > *try_fmt = ov5640_default_fmt;
> >
> > + try_crop->left = OV5640_PIXEL_ARRAY_LEFT;
> > + try_crop->top = OV5640_PIXEL_ARRAY_TOP;
> > + try_crop->width = OV5640_PIXEL_ARRAY_WIDTH;
> > + try_crop->height = OV5640_PIXEL_ARRAY_HEIGHT;
> > +
> > return 0;
> > }
> >
>
> --
> Regards,
>
> Laurent Pinchart
