media: ar0521: Adjust exposure and blankings limits

Adjust the control limits for V4L2_CID_VBLANK, V4L2_CID_HBLANK and
V4L2_CID_EXPOSURE when a new format is applied to the sensor.

Update the exposure control limits when a new blanking value is
applied and change the controls initialization to use valid values for the
default format.

The exposure control default value is changed to report the default
value of register 0x3012.
Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

drivers/media/i2c/ar0521.c

@@ -40,7 +40,8 @@
 
 #define AR0521_WIDTH_BLANKING_MIN     572u
 #define AR0521_HEIGHT_BLANKING_MIN     38u /* must be even */
-#define AR0521_TOTAL_WIDTH_MIN	     2968u
+#define AR0521_TOTAL_HEIGHT_MAX     65535u /* max_frame_length_lines */
+#define AR0521_TOTAL_WIDTH_MAX      65532u /* max_line_length_pck */
 
 #define AR0521_ANA_GAIN_MIN		0x00
 #define AR0521_ANA_GAIN_MAX		0x3f
@@ -125,8 +126,6 @@ struct ar0521_dev {
 	struct v4l2_mbus_framefmt fmt;
 	struct ar0521_ctrls ctrls;
 	unsigned int lane_count;
-	u16 total_width;
-	u16 total_height;
 	struct {
 		u16 pre;
 		u16 mult;
@@ -483,6 +482,8 @@ static int ar0521_set_fmt(struct v4l2_subdev *sd,
 			  struct v4l2_subdev_format *format)
 {
 	struct ar0521_dev *sensor = to_ar0521_dev(sd);
+	int max_vblank, max_hblank, exposure_max;
+	int ret;
 
 	ar0521_adj_fmt(&format->format);
 
@@ -493,30 +494,73 @@ static int ar0521_set_fmt(struct v4l2_subdev *sd,
 
 		fmt = v4l2_subdev_get_try_format(sd, sd_state, 0 /* pad */);
 		*fmt = format->format;
-	} else {
-		sensor->fmt = format->format;
-		ar0521_calc_mode(sensor);
+
+		mutex_unlock(&sensor->lock);
+
+		return 0;
 	}
 
+	sensor->fmt = format->format;
+	ar0521_calc_mode(sensor);
+
+	/*
+	 * Update the exposure and blankings limits. Blankings are also reset
+	 * to the minimum.
+	 */
+	max_hblank = AR0521_TOTAL_WIDTH_MAX - sensor->fmt.width;
+	ret = __v4l2_ctrl_modify_range(sensor->ctrls.hblank,
+				       sensor->ctrls.hblank->minimum,
+				       max_hblank, sensor->ctrls.hblank->step,
+				       sensor->ctrls.hblank->minimum);
+	if (ret)
+		goto unlock;
+
+	ret = __v4l2_ctrl_s_ctrl(sensor->ctrls.hblank,
+				 sensor->ctrls.hblank->minimum);
+	if (ret)
+		goto unlock;
+
+	max_vblank = AR0521_TOTAL_HEIGHT_MAX - sensor->fmt.height;
+	ret = __v4l2_ctrl_modify_range(sensor->ctrls.vblank,
+				       sensor->ctrls.vblank->minimum,
+				       max_vblank, sensor->ctrls.vblank->step,
+				       sensor->ctrls.vblank->minimum);
+	if (ret)
+		goto unlock;
+
+	ret = __v4l2_ctrl_s_ctrl(sensor->ctrls.vblank,
+				 sensor->ctrls.vblank->minimum);
+	if (ret)
+		goto unlock;
+
+	exposure_max = sensor->fmt.height + AR0521_HEIGHT_BLANKING_MIN - 4;
+	ret = __v4l2_ctrl_modify_range(sensor->ctrls.exposure,
+				       sensor->ctrls.exposure->minimum,
+				       exposure_max,
+				       sensor->ctrls.exposure->step,
+				       sensor->ctrls.exposure->default_value);
+unlock:
 	mutex_unlock(&sensor->lock);
-	return 0;
+
+	return ret;
 }
 
 static int ar0521_s_ctrl(struct v4l2_ctrl *ctrl)
 {
 	struct v4l2_subdev *sd = ctrl_to_sd(ctrl);
 	struct ar0521_dev *sensor = to_ar0521_dev(sd);
+	int exp_max;
 	int ret;
 
 	/* v4l2_ctrl_lock() locks our own mutex */
 
 	switch (ctrl->id) {
-	case V4L2_CID_HBLANK:
 	case V4L2_CID_VBLANK:
-		sensor->total_width = sensor->fmt.width +
-			sensor->ctrls.hblank->val;
-		sensor->total_height = sensor->fmt.width +
-			sensor->ctrls.vblank->val;
+		exp_max = sensor->fmt.height + ctrl->val - 4;
+		__v4l2_ctrl_modify_range(sensor->ctrls.exposure,
+					 sensor->ctrls.exposure->minimum,
+					 exp_max, sensor->ctrls.exposure->step,
+					 sensor->ctrls.exposure->default_value);
 		break;
 	}
 
@@ -574,6 +618,7 @@ static int ar0521_init_controls(struct ar0521_dev *sensor)
 	const struct v4l2_ctrl_ops *ops = &ar0521_ctrl_ops;
 	struct ar0521_ctrls *ctrls = &sensor->ctrls;
 	struct v4l2_ctrl_handler *hdl = &ctrls->handler;
+	int max_vblank, max_hblank, exposure_max;
 	struct v4l2_ctrl *link_freq;
 	int ret;
 
@@ -595,11 +640,17 @@ static int ar0521_init_controls(struct ar0521_dev *sensor)
 						-512, 511, 1, 0);
 	v4l2_ctrl_cluster(3, &ctrls->gain);
 
+	/* Initialize blanking limits using the default 2592x1944 format. */
+	max_hblank = AR0521_TOTAL_WIDTH_MAX - AR0521_WIDTH_MAX;
 	ctrls->hblank = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_HBLANK,
-					  AR0521_WIDTH_BLANKING_MIN, 4094, 1,
+					  AR0521_WIDTH_BLANKING_MIN,
+					  max_hblank, 1,
 					  AR0521_WIDTH_BLANKING_MIN);
+
+	max_vblank = AR0521_TOTAL_HEIGHT_MAX - AR0521_HEIGHT_MAX;
 	ctrls->vblank = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_VBLANK,
-					  AR0521_HEIGHT_BLANKING_MIN, 4094, 2,
+					  AR0521_HEIGHT_BLANKING_MIN,
+					  max_vblank, 2,
 					  AR0521_HEIGHT_BLANKING_MIN);
 	v4l2_ctrl_cluster(2, &ctrls->hblank);
 
@@ -609,9 +660,10 @@ static int ar0521_init_controls(struct ar0521_dev *sensor)
 					   AR0521_PIXEL_CLOCK_MAX, 1,
 					   AR0521_PIXEL_CLOCK_RATE);
 
-	/* Manual exposure time */
+	/* Manual exposure time: max exposure time = visible + blank - 4 */
+	exposure_max = AR0521_HEIGHT_MAX + AR0521_HEIGHT_BLANKING_MIN - 4;
 	ctrls->exposure = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_EXPOSURE, 0,
-					    65535, 1, 360);
+					    exposure_max, 1, 0x70);
 
 	link_freq = v4l2_ctrl_new_int_menu(hdl, ops, V4L2_CID_LINK_FREQ,
 					ARRAY_SIZE(ar0521_link_frequencies) - 1,