[PATCH 5/9] media: sun6i-csi: capture: Rework and separate format validation

[Paul Kocialkowski <paul.kocialkowski@bootlin.com>]

Introduce a new sun6i_csi_capture_format_check helper to indicate
whether a set of pixel format and mbus code are compatible.
Most of the logic is taken from sun6i_csi_capture_link_validate,
with extra checks added along the way.

Note that v4l2_format_info is now used for all pixel formats
since they should all be listed in the helper at this point.

The motivation behind this change is to pave the way for supporting
the mc-style enum_fmt.

Signed-off-by: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
---
 .../sunxi/sun6i-csi/sun6i_csi_capture.c       | 95 ++++++++++---------
 1 file changed, 49 insertions(+), 46 deletions(-)

diff --git a/drivers/media/platform/sunxi/sun6i-csi/sun6i_csi_capture.c b/drivers/media/platform/sunxi/sun6i-csi/sun6i_csi_capture.c
index cf6aadbc130b..6ce7f1d3ed57 100644
--- a/drivers/media/platform/sunxi/sun6i-csi/sun6i_csi_capture.c
+++ b/drivers/media/platform/sunxi/sun6i-csi/sun6i_csi_capture.c
@@ -327,6 +327,52 @@ static bool sun6i_csi_capture_format_match(u32 pixelformat, u32 mbus_code)
 	return false;
 }
 
+static bool sun6i_csi_capture_format_check(u32 pixelformat, u32 mbus_code)
+{
+	const struct sun6i_csi_capture_format *capture_format;
+	const struct sun6i_csi_bridge_format *bridge_format;
+	const struct v4l2_format_info *format_info;
+
+	format_info = v4l2_format_info(pixelformat);
+	if (WARN_ON(!format_info))
+		return false;
+
+	capture_format = sun6i_csi_capture_format_find(pixelformat);
+	if (WARN_ON(!capture_format))
+		return false;
+
+	bridge_format = sun6i_csi_bridge_format_find(mbus_code);
+	if (WARN_ON(!bridge_format))
+		return false;
+
+	/* Raw input is required for non-YUV formats. */
+	if (bridge_format->input_format != SUN6I_CSI_INPUT_FMT_RAW &&
+	    (format_info->pixel_enc == V4L2_PIXEL_ENC_BAYER ||
+	     format_info->pixel_enc == V4L2_PIXEL_ENC_RGB ||
+	     format_info->pixel_enc == V4L2_PIXEL_ENC_COMPRESSED))
+		return false;
+
+	if (format_info->pixel_enc == V4L2_PIXEL_ENC_YUV) {
+		/* YUV input is required for YUV pixels. */
+		if (bridge_format->input_format != SUN6I_CSI_INPUT_FMT_YUV420 &&
+		    bridge_format->input_format != SUN6I_CSI_INPUT_FMT_YUV422)
+			return false;
+
+		/* YUV420 input can't produce (upsampled) YUV422 output. */
+		if (bridge_format->input_format == SUN6I_CSI_INPUT_FMT_YUV420 &&
+		    format_info->vdiv == 1)
+			return false;
+	}
+
+	/* Raw input requires a 1:1 match between input and output. */
+	if ((bridge_format->input_format == SUN6I_CSI_INPUT_FMT_RAW ||
+	     capture_format->input_format_raw) &&
+	    !sun6i_csi_capture_format_match(pixelformat, mbus_code))
+			return false;
+
+	return true;
+}
+
 /* Capture */
 
 static void
@@ -890,28 +936,16 @@ static int sun6i_csi_capture_link_validate(struct media_link *link)
 		media_entity_to_video_device(link->sink->entity);
 	struct sun6i_csi_device *csi_dev = video_get_drvdata(video_dev);
 	struct v4l2_device *v4l2_dev = csi_dev->v4l2_dev;
-	const struct sun6i_csi_capture_format *capture_format;
-	const struct sun6i_csi_bridge_format *bridge_format;
 	unsigned int capture_width, capture_height;
 	unsigned int bridge_width, bridge_height;
-	const struct v4l2_format_info *format_info;
 	u32 pixelformat, capture_field;
 	u32 mbus_code, bridge_field;
-	bool match;
 
 	sun6i_csi_capture_dimensions(csi_dev, &capture_width, &capture_height);
-
 	sun6i_csi_capture_format(csi_dev, &pixelformat, &capture_field);
-	capture_format = sun6i_csi_capture_format_find(pixelformat);
-	if (WARN_ON(!capture_format))
-		return -EINVAL;
 
 	sun6i_csi_bridge_dimensions(csi_dev, &bridge_width, &bridge_height);
-
 	sun6i_csi_bridge_format(csi_dev, &mbus_code, &bridge_field);
-	bridge_format = sun6i_csi_bridge_format_find(mbus_code);
-	if (WARN_ON(!bridge_format))
-		return -EINVAL;
 
 	/* No cropping/scaling is supported. */
 	if (capture_width != bridge_width || capture_height != bridge_height) {
@@ -922,43 +956,12 @@ static int sun6i_csi_capture_link_validate(struct media_link *link)
 		return -EINVAL;
 	}
 
-	format_info = v4l2_format_info(pixelformat);
-	/* Some formats are not listed. */
-	if (!format_info)
-		return 0;
-
-	if (format_info->pixel_enc == V4L2_PIXEL_ENC_BAYER &&
-	    bridge_format->input_format != SUN6I_CSI_INPUT_FMT_RAW)
-		goto invalid;
-
-	if (format_info->pixel_enc == V4L2_PIXEL_ENC_RGB &&
-	    bridge_format->input_format != SUN6I_CSI_INPUT_FMT_RAW)
-		goto invalid;
-
-	if (format_info->pixel_enc == V4L2_PIXEL_ENC_YUV) {
-		if (bridge_format->input_format != SUN6I_CSI_INPUT_FMT_YUV420 &&
-		    bridge_format->input_format != SUN6I_CSI_INPUT_FMT_YUV422)
-			goto invalid;
-
-		/* YUV420 input can't produce YUV422 output. */
-		if (bridge_format->input_format == SUN6I_CSI_INPUT_FMT_YUV420 &&
-		    format_info->vdiv == 1)
-			goto invalid;
-	}
-
-	/* With raw input mode, we need a 1:1 match between input and output. */
-	if (bridge_format->input_format == SUN6I_CSI_INPUT_FMT_RAW ||
-	    capture_format->input_format_raw) {
-		match = sun6i_csi_capture_format_match(pixelformat, mbus_code);
-		if (!match)
-			goto invalid;
+	if (!sun6i_csi_capture_format_check(pixelformat, mbus_code)) {
+		v4l2_err(v4l2_dev, "invalid input/output format combination\n");
+		return -EINVAL;
 	}
 
 	return 0;
-
-invalid:
-	v4l2_err(v4l2_dev, "invalid input/output format combination\n");
-	return -EINVAL;
 }
 
 static const struct media_entity_operations sun6i_csi_capture_media_ops = {
-- 
2.39.2