media: rkisp1: Fix source pad format configuration

The ISP converts Bayer data to YUV when operating normally, and can also
operate in pass-through mode where the input and output formats must
match. Converting from YUV to Bayer isn't possible. If such an invalid
configuration is attempted, adjust it by copying the sink pad media bus
code to the source pad.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Dafna Hirschfeld <dafna@fastmail.com>
Reviewed-by: Paul Elder <paul.elder@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

drivers/media/platform/rockchip/rkisp1/rkisp1-isp.c

@@ -482,23 +482,43 @@ static void rkisp1_isp_set_src_fmt(struct rkisp1_isp *isp,
 				   struct v4l2_mbus_framefmt *format,
 				   unsigned int which)
 {
-	const struct rkisp1_mbus_info *mbus_info;
+	const struct rkisp1_mbus_info *sink_info;
+	const struct rkisp1_mbus_info *src_info;
+	struct v4l2_mbus_framefmt *sink_fmt;
 	struct v4l2_mbus_framefmt *src_fmt;
 	const struct v4l2_rect *src_crop;
 
+	sink_fmt = rkisp1_isp_get_pad_fmt(isp, sd_state,
+					  RKISP1_ISP_PAD_SINK_VIDEO, which);
 	src_fmt = rkisp1_isp_get_pad_fmt(isp, sd_state,
 					 RKISP1_ISP_PAD_SOURCE_VIDEO, which);
 	src_crop = rkisp1_isp_get_pad_crop(isp, sd_state,
 					   RKISP1_ISP_PAD_SOURCE_VIDEO, which);
 
+	/*
+	 * Media bus code. The ISP can operate in pass-through mode (Bayer in,
+	 * Bayer out or YUV in, YUV out) or process Bayer data to YUV, but
+	 * can't convert from YUV to Bayer.
+	 */
+	sink_info = rkisp1_mbus_info_get_by_code(sink_fmt->code);
+
 	src_fmt->code = format->code;
-	mbus_info = rkisp1_mbus_info_get_by_code(src_fmt->code);
-	if (!mbus_info || !(mbus_info->direction & RKISP1_ISP_SD_SRC)) {
+	src_info = rkisp1_mbus_info_get_by_code(src_fmt->code);
+	if (!src_info || !(src_info->direction & RKISP1_ISP_SD_SRC)) {
 		src_fmt->code = RKISP1_DEF_SRC_PAD_FMT;
-		mbus_info = rkisp1_mbus_info_get_by_code(src_fmt->code);
+		src_info = rkisp1_mbus_info_get_by_code(src_fmt->code);
 	}
-	if (which == V4L2_SUBDEV_FORMAT_ACTIVE)
-		isp->src_fmt = mbus_info;
+
+	if (sink_info->pixel_enc == V4L2_PIXEL_ENC_YUV &&
+	    src_info->pixel_enc == V4L2_PIXEL_ENC_BAYER) {
+		src_fmt->code = sink_fmt->code;
+		src_info = sink_info;
+	}
+
+	/*
+	 * The source width and height must be identical to the source crop
+	 * size.
+	 */
 	src_fmt->width  = src_crop->width;
 	src_fmt->height = src_crop->height;
 
@@ -508,14 +528,18 @@ static void rkisp1_isp_set_src_fmt(struct rkisp1_isp *isp,
 	 */
 	if (format->flags & V4L2_MBUS_FRAMEFMT_SET_CSC &&
 	    format->quantization == V4L2_QUANTIZATION_FULL_RANGE &&
-	    mbus_info->pixel_enc == V4L2_PIXEL_ENC_YUV)
+	    src_info->pixel_enc == V4L2_PIXEL_ENC_YUV)
 		src_fmt->quantization = V4L2_QUANTIZATION_FULL_RANGE;
-	else if (mbus_info->pixel_enc == V4L2_PIXEL_ENC_YUV)
+	else if (src_info->pixel_enc == V4L2_PIXEL_ENC_YUV)
 		src_fmt->quantization = V4L2_QUANTIZATION_LIM_RANGE;
 	else
 		src_fmt->quantization = V4L2_QUANTIZATION_FULL_RANGE;
 
 	*format = *src_fmt;
+
+	/* Store the source format info when setting the active format. */
+	if (which == V4L2_SUBDEV_FORMAT_ACTIVE)
+		isp->src_fmt = src_info;
 }
 
 static void rkisp1_isp_set_src_crop(struct rkisp1_isp *isp,