Hi Jacopo,
Thank you for the patch.
On Mon, Jan 31, 2022 at 03:32:35PM +0100, Jacopo Mondi wrote:
> Add the VBLANK control which allows to select the duration of the
> frame vertical blankings and allows to control the framerate.
>
> The VBLANK control also modifies the exposure time range, which cannot
> exceed the maximum frame length.
>
> Signed-off-by: Jacopo Mondi <jacopo@xxxxxxxxxx>
> ---
> drivers/media/i2c/ov5640.c | 50 ++++++++++++++++++++++++++++++++++++++
> 1 file changed, 50 insertions(+)
>
> diff --git a/drivers/media/i2c/ov5640.c b/drivers/media/i2c/ov5640.c
> index b2961e8e07c3..6eeb50724195 100644
> --- a/drivers/media/i2c/ov5640.c
> +++ b/drivers/media/i2c/ov5640.c
> @@ -31,6 +31,10 @@
>
> #define OV5640_LINK_RATE_MAX 490000000U
>
> +/* FIXME: not documented. */
> +#define OV5640_MIN_VBLANK 24
> +#define OV5640_MAX_VTS 1968
> +
> #define OV5640_DEFAULT_SLAVE_ID 0x3c
>
> #define OV5640_REG_SYS_RESET02 0x3002
> @@ -267,6 +271,7 @@ struct ov5640_ctrls {
> struct v4l2_ctrl *pixel_rate;
> struct v4l2_ctrl *link_freq;
> struct v4l2_ctrl *hblank;
> + struct v4l2_ctrl *vblank;
> struct {
> struct v4l2_ctrl *auto_exp;
> struct v4l2_ctrl *exposure;
> @@ -2531,6 +2536,7 @@ static int ov5640_update_pixel_rate(struct ov5640_dev *sensor)
> struct v4l2_mbus_framefmt *fmt = &sensor->fmt;
> enum ov5640_pixel_rate_id pixel_rate_id = mode->pixel_rate;
> u32 num_lanes = sensor->ep.bus.mipi_csi2.num_data_lanes;
> + s64 exposure_val, exposure_max;
> unsigned int hblank;
> unsigned int i = 0;
> u32 pixel_rate;
> @@ -2586,6 +2592,20 @@ static int ov5640_update_pixel_rate(struct ov5640_dev *sensor)
> __v4l2_ctrl_modify_range(sensor->ctrls.hblank,
> hblank, hblank, 1, hblank);
>
> + __v4l2_ctrl_modify_range(sensor->ctrls.vblank,
> + OV5640_MIN_VBLANK,
> + OV5640_MAX_VTS - mode->crop.height, 1,
> + mode->vblank_def);
> + __v4l2_ctrl_s_ctrl(sensor->ctrls.vblank, mode->vblank_def);
> +
> + exposure_max = mode->crop.height + mode->vblank_def - OV5640_MIN_VBLANK;
There's typically a fixed margin of a few lines between the maximum
exposure and the total vertical size, but that's usually smaller than
the minimum vblank value. Are you sure OV5640_MIN_VBLANK is right here ?
> + exposure_val = clamp((s64)sensor->ctrls.exposure->val,
> + (s64)sensor->ctrls.exposure->minimum,
> + (s64)exposure_max);
> + __v4l2_ctrl_modify_range(sensor->ctrls.exposure,
> + sensor->ctrls.exposure->minimum,
> + exposure_max, 1, exposure_val);
> +
> return 0;
> }
>
> @@ -2958,6 +2978,15 @@ static int ov5640_set_ctrl_vflip(struct ov5640_dev *sensor, int value)
> (BIT(2) | BIT(1)) : 0);
> }
>
> +static int ov5640_set_ctrl_vblank(struct ov5640_dev *sensor, int value)
> +{
> + const struct ov5640_mode_info *mode = sensor->current_mode;
> +
> + /* Update the VTOT timing register value. */
> + return ov5640_write_reg16(sensor, OV5640_REG_TIMING_VTS,
> + mode->crop.height + value);
> +}
> +
> static int ov5640_g_volatile_ctrl(struct v4l2_ctrl *ctrl)
> {
> struct v4l2_subdev *sd = ctrl_to_sd(ctrl);
> @@ -2988,10 +3017,22 @@ static int ov5640_s_ctrl(struct v4l2_ctrl *ctrl)
> {
> struct v4l2_subdev *sd = ctrl_to_sd(ctrl);
> struct ov5640_dev *sensor = to_ov5640_dev(sd);
> + const struct ov5640_mode_info *mode = sensor->current_mode;
> int ret;
>
> /* v4l2_ctrl_lock() locks our own mutex */
>
> + switch (ctrl->id) {
> + case V4L2_CID_VBLANK:
> + /* Update the exposure range to the newly programmed vblank. */
> + unsigned int max = mode->crop.height + ctrl->val - OV5640_MIN_VBLANK;
> +
> + __v4l2_ctrl_modify_range(sensor->ctrls.exposure,
> + sensor->ctrls.exposure->minimum,
> + max, sensor->ctrls.exposure->step, max);
Should the default be set to mode->vblank_def ?
> + break;
> + }
> +
> /*
> * If the device is not powered up by the host driver do
> * not apply any controls to H/W at this time. Instead
> @@ -3031,6 +3072,9 @@ static int ov5640_s_ctrl(struct v4l2_ctrl *ctrl)
> case V4L2_CID_VFLIP:
> ret = ov5640_set_ctrl_vflip(sensor, ctrl->val);
> break;
> + case V4L2_CID_VBLANK:
> + ret = ov5640_set_ctrl_vblank(sensor, ctrl->val);
> + break;
> default:
> ret = -EINVAL;
> break;
> @@ -3050,6 +3094,7 @@ static int ov5640_init_controls(struct ov5640_dev *sensor)
> const struct v4l2_ctrl_ops *ops = &ov5640_ctrl_ops;
> struct ov5640_ctrls *ctrls = &sensor->ctrls;
> struct v4l2_ctrl_handler *hdl = &ctrls->handler;
> + unsigned int max_vblank;
> unsigned int hblank;
> int ret;
>
> @@ -3073,6 +3118,11 @@ static int ov5640_init_controls(struct ov5640_dev *sensor)
> ctrls->hblank = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_HBLANK, hblank,
> hblank, 1, hblank);
>
> + max_vblank = OV5640_MAX_VTS - mode->crop.height;
> + ctrls->vblank = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_VBLANK,
> + OV5640_MIN_VBLANK, max_vblank,
> + 1, mode->vblank_def);
> +
> /* Auto/manual white balance */
> ctrls->auto_wb = v4l2_ctrl_new_std(hdl, ops,
> V4L2_CID_AUTO_WHITE_BALANCE,
--
Regards,
Laurent Pinchart
