[PATCH v3 1/2] media: rkisp1-isp: Set correct data mode for YUV bypass

[Alen Karnil]

When the ISP sink is YUV, the ISP is in 'bypass' or passthrough mode,
the current isp mode produces a garbled image, and in testing, setting
to data mode produces a correct image.

Replace references to ITU601 to DATA_MODE and add a comment to explain.

Tested with OV5640 and I.MX8MPlus.

Signed-off-by: Alen Karnil <alen.karnil at ideasonboard.com>

---
v3:
 - Taken over from list and refreshed
 - Removed always true conditional check
 - Reworded commit mesasge to better represent changes
---
 drivers/media/platform/rockchip/rkisp1/rkisp1-isp.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/drivers/media/platform/rockchip/rkisp1/rkisp1-isp.c b/drivers/media/platform/rockchip/rkisp1/rkisp1-isp.c
index 2311672cedb1..4de44f6ec753 100644
--- a/drivers/media/platform/rockchip/rkisp1/rkisp1-isp.c
+++ b/drivers/media/platform/rockchip/rkisp1/rkisp1-isp.c
@@ -240,13 +240,18 @@ static int rkisp1_config_isp(struct rkisp1_isp *isp,
 		}
 	} else if (sink_fmt->pixel_enc == V4L2_PIXEL_ENC_YUV) {
 		acq_mult = 2;
+		/*
+		 * The datasheet specifies using ITU601 mode for YUV,
+		 * however that results in a garbled image, data mode
+		 * does not exhibit this.
+		 */
 		if (mbus_type == V4L2_MBUS_CSI2_DPHY) {
-			isp_ctrl = RKISP1_CIF_ISP_CTRL_ISP_MODE_ITU601;
+			isp_ctrl = RKISP1_CIF_ISP_CTRL_ISP_MODE_DATA_MODE;
 		} else {
 			if (mbus_type == V4L2_MBUS_BT656)
 				isp_ctrl = RKISP1_CIF_ISP_CTRL_ISP_MODE_ITU656;
 			else
-				isp_ctrl = RKISP1_CIF_ISP_CTRL_ISP_MODE_ITU601;
+				isp_ctrl = RKISP1_CIF_ISP_CTRL_ISP_MODE_DATA_MODE;
 		}
 
 		irq_mask |= RKISP1_CIF_ISP_DATA_LOSS;

-- 
2.53.0