media: i2c: Add hblank control to ov8865

Add a V4L2_CID_HBLANK control to the ov8865 driver. This is read only
with timing control intended to be done via vblanking alone.

Signed-off-by: Daniel Scally <djrscally@gmail.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

drivers/media/i2c/ov8865.c

@@ -677,6 +677,7 @@ struct ov8865_state {
 struct ov8865_ctrls {
 	struct v4l2_ctrl *link_freq;
 	struct v4l2_ctrl *pixel_rate;
+	struct v4l2_ctrl *hblank;
 	struct v4l2_ctrl *vblank;
 
 	struct v4l2_ctrl_handler handler;
@@ -2513,6 +2514,7 @@ static int ov8865_ctrls_init(struct ov8865_sensor *sensor)
 	const struct v4l2_ctrl_ops *ops = &ov8865_ctrl_ops;
 	const struct ov8865_mode *mode = &ov8865_modes[0];
 	unsigned int vblank_max, vblank_def;
+	unsigned int hblank;
 	int ret;
 
 	v4l2_ctrl_handler_init(handler, 32);
@@ -2550,6 +2552,13 @@ static int ov8865_ctrls_init(struct ov8865_sensor *sensor)
 				     0, 0, ov8865_test_pattern_menu);
 
 	/* Blanking */
+	hblank = mode->hts - mode->output_size_x;
+	ctrls->hblank = v4l2_ctrl_new_std(handler, ops, V4L2_CID_HBLANK, hblank,
+					  hblank, 1, hblank);
+
+	if (ctrls->hblank)
+		ctrls->hblank->flags |= V4L2_CTRL_FLAG_READ_ONLY;
+
 	vblank_max = OV8865_TIMING_MAX_VTS - mode->output_size_y;
 	vblank_def = mode->vts - mode->output_size_y;
 	ctrls->vblank = v4l2_ctrl_new_std(handler, ops, V4L2_CID_VBLANK,
@@ -2696,6 +2705,7 @@ static int ov8865_set_fmt(struct v4l2_subdev *subdev,
 	struct v4l2_mbus_framefmt *mbus_format = &format->format;
 	const struct ov8865_mode *mode;
 	u32 mbus_code = 0;
+	unsigned int hblank;
 	unsigned int index;
 	int ret = 0;
 
@@ -2740,6 +2750,10 @@ static int ov8865_set_fmt(struct v4l2_subdev *subdev,
 				 OV8865_TIMING_MAX_VTS - mode->output_size_y,
 				 1, mode->vts - mode->output_size_y);
 
+	hblank = mode->hts - mode->output_size_x;
+	__v4l2_ctrl_modify_range(sensor->ctrls.hblank, hblank, hblank, 1,
+				 hblank);
+
 complete:
 	mutex_unlock(&sensor->mutex);