media: i2c: ov4689: Make horizontal blanking configurable

Make horizontal blanking configurable. To do so, set HTS register
according to the requested horizontal blanking in ov4689_set_ctrl
instead of the register table. Default HTS value is not changed by
this patch. Minimal HTS value is found experimentally and corresponds
to 90 fps framerate at minimum vertical blanking. Real HTS value is
the register value multiplied by 4.
Signed-off-by: Mikhail Rudenko <mike.rudenko@gmail.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

drivers/media/i2c/ov4689.c

@@ -30,13 +30,17 @@
 #define OV4689_REG_EXPOSURE		CCI_REG24(0x3500)
 #define OV4689_EXPOSURE_MIN		4
 #define OV4689_EXPOSURE_STEP		1
-#define OV4689_VTS_MAX			0x7fff
 
 #define OV4689_REG_GAIN			CCI_REG16(0x3508)
 #define OV4689_GAIN_STEP		1
 #define OV4689_GAIN_DEFAULT		0x80
 
+#define OV4689_REG_HTS			CCI_REG16(0x380c)
+#define OV4689_HTS_DIVIDER		4
+#define OV4689_HTS_MAX			0x7fff
+
 #define OV4689_REG_VTS			CCI_REG16(0x380e)
+#define OV4689_VTS_MAX			0x7fff
 
 #define OV4689_REG_TEST_PATTERN		CCI_REG8(0x5040)
 #define OV4689_TEST_PATTERN_ENABLE	0x80
@@ -61,6 +65,7 @@ struct ov4689_mode {
 	u32 width;
 	u32 height;
 	u32 hts_def;
+	u32 hts_min;
 	u32 vts_def;
 	u32 exp_def;
 	u32 pixel_rate;
@@ -104,7 +109,7 @@ struct ov4689_gain_range {
 
 /*
  * Xclk 24Mhz
- * max_framerate 30fps
+ * max_framerate 90fps
  * mipi_datarate per lane 1008Mbps
  */
 static const struct cci_reg_sequence ov4689_2688x1520_regs[] = {
@@ -175,8 +180,6 @@ static const struct cci_reg_sequence ov4689_2688x1520_regs[] = {
 	/* Timing control */
 	{ CCI_REG8(0x3801), 0x08 }, /* H_CROP_START_L h_crop_start[7:0] = 0x08 */
 	{ CCI_REG8(0x3805), 0x97 }, /* H_CROP_END_L h_crop_end[7:0] = 0x97 */
-	{ CCI_REG8(0x380c), 0x0a }, /* TIMING_HTS_H hts[14:8] = 0x0a */
-	{ CCI_REG8(0x380d), 0x0e }, /* TIMING_HTS_L hts[7:0] = 0x0e */
 	{ CCI_REG8(0x3811), 0x08 }, /* H_WIN_OFF_L h_win_off[7:0] = 0x08*/
 	{ CCI_REG8(0x3813), 0x04 }, /* V_WIN_OFF_L v_win_off[7:0] = 0x04 */
 	{ CCI_REG8(0x3819), 0x01 }, /* VSYNC_END_L vsync_end_point[7:0] = 0x01 */
@@ -237,7 +240,8 @@ static const struct ov4689_mode supported_modes[] = {
 		.crop_top = 8,
 		.crop_left = 16,
 		.exp_def = 1536,
-		.hts_def = 4 * 2574,
+		.hts_def = 10296,
+		.hts_min = 3432,
 		.vts_def = 1554,
 		.pixel_rate = 480000000,
 		.reg_list = ov4689_2688x1520_regs,
@@ -598,6 +602,11 @@ static int ov4689_set_ctrl(struct v4l2_ctrl *ctrl)
 	case V4L2_CID_TEST_PATTERN:
 		ret = ov4689_enable_test_pattern(ov4689, ctrl->val);
 		break;
+	case V4L2_CID_HBLANK:
+		cci_write(regmap, OV4689_REG_HTS,
+			  (ctrl->val + ov4689->cur_mode->width) /
+			  OV4689_HTS_DIVIDER, &ret);
+		break;
 	default:
 		dev_warn(dev, "%s Unhandled id:0x%x, val:0x%x\n",
 			 __func__, ctrl->id, ctrl->val);
@@ -622,8 +631,8 @@ static int ov4689_initialize_controls(struct ov4689 *ov4689)
 	struct v4l2_ctrl_handler *handler;
 	const struct ov4689_mode *mode;
 	s64 exposure_max, vblank_def;
+	s64 hblank_def, hblank_min;
 	struct v4l2_ctrl *ctrl;
-	s64 h_blank_def;
 	int ret;
 
 	handler = &ov4689->ctrl_handler;
@@ -640,11 +649,11 @@ static int ov4689_initialize_controls(struct ov4689 *ov4689)
 	v4l2_ctrl_new_std(handler, NULL, V4L2_CID_PIXEL_RATE, 0,
 			  mode->pixel_rate, 1, mode->pixel_rate);
 
-	h_blank_def = mode->hts_def - mode->width;
-	ctrl = v4l2_ctrl_new_std(handler, NULL, V4L2_CID_HBLANK, h_blank_def,
-				 h_blank_def, 1, h_blank_def);
-	if (ctrl)
-		ctrl->flags |= V4L2_CTRL_FLAG_READ_ONLY;
+	hblank_def = mode->hts_def - mode->width;
+	hblank_min = mode->hts_min - mode->width;
+	v4l2_ctrl_new_std(handler, &ov4689_ctrl_ops, V4L2_CID_HBLANK,
+			  hblank_min, OV4689_HTS_MAX - mode->width,
+			  OV4689_HTS_DIVIDER, hblank_def);
 
 	vblank_def = mode->vts_def - mode->height;
 	v4l2_ctrl_new_std(handler, &ov4689_ctrl_ops, V4L2_CID_VBLANK,