media: visl: add virtual stateless decoder driver

A virtual stateless device for stateless uAPI development purposes.

This tool's objective is to help the development and testing of
userspace applications that use the V4L2 stateless API to decode media.

A userspace implementation can use visl to run a decoding loop even when
no hardware is available or when the kernel uAPI for the codec has not
been upstreamed yet. This can reveal bugs at an early stage.

This driver can also trace the contents of the V4L2 controls submitted
to it.  It can also dump the contents of the vb2 buffers through a
debugfs interface. This is in many ways similar to the tracing
infrastructure available for other popular encode/decode APIs out there
and can help develop a userspace application by using another (working)
one as a reference.

Note that no actual decoding of video frames is performed by visl. The
V4L2 test pattern generator is used to write various debug information
to the capture buffers instead.

Signed-off-by: Daniel Almeida <daniel.almeida@collabora.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

1 files changed, 67 insertions, 0 deletions

diff --git a/drivers/media/test-drivers/visl/visl-dec.h b/drivers/media/test-drivers/visl/visl-dec.h
new file mode 100644
index 000000000000..4a706a9de02e
--- /dev/null
+++ b/drivers/media/test-drivers/visl/visl-dec.h
@@ -0,0 +1,67 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Contains the virtual decoder logic. The functions here control the
+ * tracing/TPG on a per-frame basis
+ */
+
+#ifndef _VISL_DEC_H_
+#define _VISL_DEC_H_
+
+#include "visl.h"
+
+struct visl_fwht_run {
+	const struct v4l2_ctrl_fwht_params *params;
+};
+
+struct visl_mpeg2_run {
+	const struct v4l2_ctrl_mpeg2_sequence *seq;
+	const struct v4l2_ctrl_mpeg2_picture *pic;
+	const struct v4l2_ctrl_mpeg2_quantisation *quant;
+};
+
+struct visl_vp8_run {
+	const struct v4l2_ctrl_vp8_frame *frame;
+};
+
+struct visl_vp9_run {
+	const struct v4l2_ctrl_vp9_frame *frame;
+	const struct v4l2_ctrl_vp9_compressed_hdr *probs;
+};
+
+struct visl_h264_run {
+	const struct v4l2_ctrl_h264_sps *sps;
+	const struct v4l2_ctrl_h264_pps *pps;
+	const struct v4l2_ctrl_h264_scaling_matrix *sm;
+	const struct v4l2_ctrl_h264_slice_params *spram;
+	const struct v4l2_ctrl_h264_decode_params *dpram;
+	const struct v4l2_ctrl_h264_pred_weights *pwht;
+};
+
+struct visl_hevc_run {
+	const struct v4l2_ctrl_hevc_sps *sps;
+	const struct v4l2_ctrl_hevc_pps *pps;
+	const struct v4l2_ctrl_hevc_slice_params *spram;
+	const struct v4l2_ctrl_hevc_scaling_matrix *sm;
+	const struct v4l2_ctrl_hevc_decode_params *dpram;
+};
+
+struct visl_run {
+	struct vb2_v4l2_buffer	*src;
+	struct vb2_v4l2_buffer	*dst;
+
+	union {
+		struct visl_fwht_run	fwht;
+		struct visl_mpeg2_run	mpeg2;
+		struct visl_vp8_run	vp8;
+		struct visl_vp9_run	vp9;
+		struct visl_h264_run	h264;
+		struct visl_hevc_run	hevc;
+	};
+};
+
+int visl_dec_start(struct visl_ctx *ctx);
+int visl_dec_stop(struct visl_ctx *ctx);
+int visl_job_ready(void *priv);
+void visl_device_run(void *priv);
+
+#endif /* _VISL_DEC_H_ */