[RFC PATCH 3/8] media: hantro: Support format filtering by depth

[Jernej Skrabec]

In preparation for supporting 10-bit formats, add mechanism which will
filter formats based on pixel depth.

Hantro G2 supports only one decoding format natively and that is based
on bit depth of current video frame. Additionally, it makes no sense to
upconvert bitness, so filter those out too.

Signed-off-by: Jernej Skrabec <jernej.skrabec at gmail.com>
---
 drivers/staging/media/hantro/hantro.h      |  4 ++
 drivers/staging/media/hantro/hantro_v4l2.c | 48 ++++++++++++++++++++--
 drivers/staging/media/hantro/hantro_v4l2.h |  1 +
 3 files changed, 50 insertions(+), 3 deletions(-)

diff --git a/drivers/staging/media/hantro/hantro.h b/drivers/staging/media/hantro/hantro.h
index 06d0f3597694..c6525ee8d89a 100644
--- a/drivers/staging/media/hantro/hantro.h
+++ b/drivers/staging/media/hantro/hantro.h
@@ -227,6 +227,7 @@ struct hantro_dev {
  *
  * @ctrl_handler:	Control handler used to register controls.
  * @jpeg_quality:	User-specified JPEG compression quality.
+ * @bit_depth:		Bit depth of current frame
  *
  * @codec_ops:		Set of operations related to codec mode.
  * @postproc:		Post-processing context.
@@ -252,6 +253,7 @@ struct hantro_ctx {
 
 	struct v4l2_ctrl_handler ctrl_handler;
 	int jpeg_quality;
+	int bit_depth;
 
 	const struct hantro_codec_ops *codec_ops;
 	struct hantro_postproc_ctx postproc;
@@ -278,6 +280,7 @@ struct hantro_ctx {
  * @enc_fmt:	Format identifier for encoder registers.
  * @frmsize:	Supported range of frame sizes (only for bitstream formats).
  * @postprocessed: Indicates if this format needs the post-processor.
+ * @match_depth: Indicates if format bit depth must match video bit depth
  */
 struct hantro_fmt {
 	char *name;
@@ -288,6 +291,7 @@ struct hantro_fmt {
 	enum hantro_enc_fmt enc_fmt;
 	struct v4l2_frmsize_stepwise frmsize;
 	bool postprocessed;
+	bool match_depth;
 };
 
 struct hantro_reg {
diff --git a/drivers/staging/media/hantro/hantro_v4l2.c b/drivers/staging/media/hantro/hantro_v4l2.c
index e595905b3bd7..1214fa2f64ae 100644
--- a/drivers/staging/media/hantro/hantro_v4l2.c
+++ b/drivers/staging/media/hantro/hantro_v4l2.c
@@ -64,6 +64,42 @@ hantro_get_postproc_formats(const struct hantro_ctx *ctx,
 	return ctx->dev->variant->postproc_fmts;
 }
 
+int hantro_get_formath_depth(u32 fourcc)
+{
+	switch (fourcc) {
+	case V4L2_PIX_FMT_P010:
+	case V4L2_PIX_FMT_P010_4L4:
+		return 10;
+	default:
+		return 8;
+	}
+}
+
+static bool
+hantro_check_depth_match(const struct hantro_ctx *ctx,
+			 const struct hantro_fmt *fmt)
+{
+	int fmt_depth, ctx_depth = 8;
+
+	if (!fmt->match_depth && !fmt->postprocessed)
+		return true;
+
+	/* 0 means default depth, which is 8 */
+	if (ctx->bit_depth)
+		ctx_depth = ctx->bit_depth;
+
+	fmt_depth = hantro_get_formath_depth(fmt->fourcc);
+
+	/*
+	 * Allow only downconversion for postproc formats for now.
+	 * It may be possible to relax that on some HW.
+	 */
+	if (!fmt->match_depth)
+		return fmt_depth <= ctx_depth;
+
+	return fmt_depth == ctx_depth;
+}
+
 static const struct hantro_fmt *
 hantro_find_format(const struct hantro_ctx *ctx, u32 fourcc)
 {
@@ -91,7 +127,8 @@ hantro_get_default_fmt(const struct hantro_ctx *ctx, bool bitstream)
 	formats = hantro_get_formats(ctx, &num_fmts);
 	for (i = 0; i < num_fmts; i++) {
 		if (bitstream == (formats[i].codec_mode !=
-				  HANTRO_MODE_NONE))
+				  HANTRO_MODE_NONE) &&
+		    hantro_check_depth_match(ctx, &formats[i]))
 			return &formats[i];
 	}
 	return NULL;
@@ -163,11 +200,13 @@ static int vidioc_enum_fmt(struct file *file, void *priv,
 	formats = hantro_get_formats(ctx, &num_fmts);
 	for (i = 0; i < num_fmts; i++) {
 		bool mode_none = formats[i].codec_mode == HANTRO_MODE_NONE;
+		fmt = &formats[i];
 
 		if (skip_mode_none == mode_none)
 			continue;
+		if (!hantro_check_depth_match(ctx, fmt))
+			continue;
 		if (j == f->index) {
-			fmt = &formats[i];
 			f->pixelformat = fmt->fourcc;
 			return 0;
 		}
@@ -183,8 +222,11 @@ static int vidioc_enum_fmt(struct file *file, void *priv,
 		return -EINVAL;
 	formats = hantro_get_postproc_formats(ctx, &num_fmts);
 	for (i = 0; i < num_fmts; i++) {
+		fmt = &formats[i];
+
+		if (!hantro_check_depth_match(ctx, fmt))
+			continue;
 		if (j == f->index) {
-			fmt = &formats[i];
 			f->pixelformat = fmt->fourcc;
 			return 0;
 		}
diff --git a/drivers/staging/media/hantro/hantro_v4l2.h b/drivers/staging/media/hantro/hantro_v4l2.h
index 18bc682c8556..f4a5905ed518 100644
--- a/drivers/staging/media/hantro/hantro_v4l2.h
+++ b/drivers/staging/media/hantro/hantro_v4l2.h
@@ -22,5 +22,6 @@ extern const struct v4l2_ioctl_ops hantro_ioctl_ops;
 extern const struct vb2_ops hantro_queue_ops;
 
 void hantro_reset_fmts(struct hantro_ctx *ctx);
+int hantro_get_formath_depth(u32 fourcc);
 
 #endif /* HANTRO_V4L2_H_ */
-- 
2.35.1