media: i2c: ov4689: Implement vflip/hflip controls

The OV4689 sensor supports horizontal and vertical flipping. Add
appropriate controls to the driver. Toggling both array flip and
digital flip bits allows to achieve flipping while maintaining output
Bayer order. Note that the default value of hflip control corresponds
to both bits set, as it was before this patch.
Signed-off-by: Mikhail Rudenko <mike.rudenko@gmail.com>
Reviewed-by: Kieran Bingham <kieran.bingham@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

@@ -42,6 +42,14 @@
 #define OV4689_REG_VTS			CCI_REG16(0x380e)
 #define OV4689_VTS_MAX			0x7fff
 
+#define OV4689_REG_TIMING_FORMAT1	CCI_REG8(0x3820) /* Vertical */
+#define OV4689_REG_TIMING_FORMAT2	CCI_REG8(0x3821) /* Horizontal */
+#define OV4689_TIMING_FLIP_MASK		GENMASK(2, 1)
+#define OV4689_TIMING_FLIP_ARRAY	BIT(1)
+#define OV4689_TIMING_FLIP_DIGITAL	BIT(2)
+#define OV4689_TIMING_FLIP_BOTH		(OV4689_TIMING_FLIP_ARRAY |\
+					 OV4689_TIMING_FLIP_DIGITAL)
+
 #define OV4689_REG_TEST_PATTERN		CCI_REG8(0x5040)
 #define OV4689_TEST_PATTERN_ENABLE	0x80
 #define OV4689_TEST_PATTERN_DISABLE	0x0
@@ -183,7 +191,6 @@ static const struct cci_reg_sequence ov4689_2688x1520_regs[] = {
 	{ 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 */
-	{ CCI_REG8(0x3821), 0x06 }, /* TIMING_FORMAT2 array_h_mirror = 1, digital_h_mirror = 1 */
 
 	/* OTP control */
 	{ CCI_REG8(0x3d85), 0x36 }, /* OTP_REG85 OTP_power_up_load_setting_enable = 1,
@@ -607,6 +614,16 @@ static int ov4689_set_ctrl(struct v4l2_ctrl *ctrl)
 			  (ctrl->val + ov4689->cur_mode->width) /
 			  OV4689_HTS_DIVIDER, &ret);
 		break;
+	case V4L2_CID_VFLIP:
+		cci_update_bits(regmap, OV4689_REG_TIMING_FORMAT1,
+				OV4689_TIMING_FLIP_MASK,
+				ctrl->val ? OV4689_TIMING_FLIP_BOTH : 0, &ret);
+		break;
+	case V4L2_CID_HFLIP:
+		cci_update_bits(regmap, OV4689_REG_TIMING_FORMAT2,
+				OV4689_TIMING_FLIP_MASK,
+				ctrl->val ? 0 : OV4689_TIMING_FLIP_BOTH, &ret);
+		break;
 	default:
 		dev_warn(dev, "%s Unhandled id:0x%x, val:0x%x\n",
 			 __func__, ctrl->id, ctrl->val);
@@ -637,7 +654,7 @@ static int ov4689_initialize_controls(struct ov4689 *ov4689)
 
 	handler = &ov4689->ctrl_handler;
 	mode = ov4689->cur_mode;
-	ret = v4l2_ctrl_handler_init(handler, 10);
+	ret = v4l2_ctrl_handler_init(handler, 12);
 	if (ret)
 		return ret;
 
@@ -677,6 +694,9 @@ static int ov4689_initialize_controls(struct ov4689 *ov4689)
 				     ARRAY_SIZE(ov4689_test_pattern_menu) - 1,
 				     0, 0, ov4689_test_pattern_menu);
 
+	v4l2_ctrl_new_std(handler, &ov4689_ctrl_ops, V4L2_CID_VFLIP, 0, 1, 1, 0);
+	v4l2_ctrl_new_std(handler, &ov4689_ctrl_ops, V4L2_CID_HFLIP, 0, 1, 1, 0);
+
 	if (handler->error) {
 		ret = handler->error;
 		dev_err(ov4689->dev, "Failed to init controls(%d)\n", ret);