media: i2c: imx283: Update exposure range on blanking changes

The exposure ranges are updated currently whenever the VBLANK control
is updated.

However, the total exposure limits are a factor of both the HBLANK and
the VBLANK durations.

Determine the hmax value any time the control is set, including
if the device is not yet streaming and update the limits accordingly.

Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>

Author: kbingham

drivers/media/i2c/imx283.c

@@ -857,7 +857,7 @@ static int imx283_set_ctrl(struct v4l2_ctrl *ctrl)
 	const struct imx283_mode *mode_list;
 	struct v4l2_subdev_state *state;
 	unsigned int num_modes;
-	u64 shr, pixel_rate;
+	u64 shr;
 	int ret = 0;
 
 	state = v4l2_subdev_get_locked_active_state(&imx283->sd);
@@ -868,15 +868,24 @@ static int imx283_set_ctrl(struct v4l2_ctrl *ctrl)
 				      fmt->width, fmt->height);
 
 	/*
-	 * The VBLANK control may change the limits of usable exposure, so check
-	 * and adjust if necessary.
+	 * The VBLANK/HBLANK controls change the limits of usable exposure,
+	 * so check and adjust if necessary.
 	 */
-	if (ctrl->id == V4L2_CID_VBLANK) {
-		/* Honour the VBLANK limits when setting exposure. */
-		s64 current_exposure, max_exposure, min_exposure;
+	if (ctrl->id == V4L2_CID_HBLANK) {
+		u64 pixel_rate = imx283_pixel_rate(imx283, mode);
+		u32 max_width = mode->crop.width + ctrl->val;
+
+		imx283->hmax = imx283_internal_clock(pixel_rate, max_width);
+	}
 
+	if (ctrl->id == V4L2_CID_VBLANK)
 		imx283->vmax = mode->crop.height + ctrl->val;
 
+	if (ctrl->id == V4L2_CID_HBLANK ||
+	    ctrl->id == V4L2_CID_VBLANK) {
+		/* Honour the VBLANK limits when setting exposure. */
+		s64 current_exposure, max_exposure, min_exposure;
+
 		imx283_exposure_limits(imx283, mode,
 				       &min_exposure, &max_exposure);
 
@@ -904,8 +913,6 @@ static int imx283_set_ctrl(struct v4l2_ctrl *ctrl)
 		break;
 
 	case V4L2_CID_HBLANK:
-		pixel_rate = imx283_pixel_rate(imx283, mode);
-		imx283->hmax = imx283_internal_clock(pixel_rate, mode->crop.width + ctrl->val);
 		dev_dbg(imx283->dev, "V4L2_CID_HBLANK : %d  HMAX : %u\n",
 			ctrl->val, imx283->hmax);
 		ret = cci_write(imx283->cci, IMX283_REG_HMAX, imx283->hmax, NULL);