[PATCH v2 3/6] media: v4l2-mem2mem: add stateless_(try_)decoder_cmd ioctl helpers

[Jernej Skrabec <jernej.skrabec@xxxxxxxx>]

These helpers are used by stateless codecs when they support multiple
slices per frame and hold capture buffer flag is set. It's expected that
all such codecs will use this code.

Signed-off-by: Jernej Skrabec <jernej.skrabec@xxxxxxxx>
---
 drivers/media/v4l2-core/v4l2-mem2mem.c | 35 ++++++++++++++++++++++++++
 include/media/v4l2-mem2mem.h           |  4 +++
 2 files changed, 39 insertions(+)

diff --git a/drivers/media/v4l2-core/v4l2-mem2mem.c b/drivers/media/v4l2-core/v4l2-mem2mem.c
index 19937dd3c6f6..2677a07e4c9b 100644
--- a/drivers/media/v4l2-core/v4l2-mem2mem.c
+++ b/drivers/media/v4l2-core/v4l2-mem2mem.c
@@ -1154,6 +1154,41 @@ int v4l2_m2m_ioctl_try_decoder_cmd(struct file *file, void *fh,
 }
 EXPORT_SYMBOL_GPL(v4l2_m2m_ioctl_try_decoder_cmd);
 
+int v4l2_m2m_ioctl_stateless_try_decoder_cmd(struct file *file, void *fh,
+					     struct v4l2_decoder_cmd *dc)
+{
+	if (dc->cmd != V4L2_DEC_CMD_FLUSH)
+		return -EINVAL;
+
+	dc->flags = 0;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(v4l2_m2m_ioctl_stateless_try_decoder_cmd);
+
+int v4l2_m2m_ioctl_stateless_decoder_cmd(struct file *file, void *priv,
+					 struct v4l2_decoder_cmd *dc)
+{
+	struct v4l2_fh *fh = file->private_data;
+	struct vb2_v4l2_buffer *out_vb, *cap_vb;
+	int ret;
+
+	ret = v4l2_m2m_ioctl_stateless_try_decoder_cmd(file, priv, dc);
+	if (ret < 0)
+		return ret;
+
+	out_vb = v4l2_m2m_last_src_buf(fh->m2m_ctx);
+	cap_vb = v4l2_m2m_last_dst_buf(fh->m2m_ctx);
+
+	if (out_vb)
+		out_vb->flags &= ~V4L2_BUF_FLAG_M2M_HOLD_CAPTURE_BUF;
+	else if (cap_vb && cap_vb->is_held)
+		v4l2_m2m_buf_done(cap_vb, VB2_BUF_STATE_DONE);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(v4l2_m2m_ioctl_stateless_decoder_cmd);
+
 /*
  * v4l2_file_operations helpers. It is assumed here same lock is used
  * for the output and the capture buffer queue.
diff --git a/include/media/v4l2-mem2mem.h b/include/media/v4l2-mem2mem.h
index c9fa96c8eed1..8ae2f56c7fa3 100644
--- a/include/media/v4l2-mem2mem.h
+++ b/include/media/v4l2-mem2mem.h
@@ -714,6 +714,10 @@ int v4l2_m2m_ioctl_try_encoder_cmd(struct file *file, void *fh,
 				   struct v4l2_encoder_cmd *ec);
 int v4l2_m2m_ioctl_try_decoder_cmd(struct file *file, void *fh,
 				   struct v4l2_decoder_cmd *dc);
+int v4l2_m2m_ioctl_stateless_try_decoder_cmd(struct file *file, void *fh,
+					     struct v4l2_decoder_cmd *dc);
+int v4l2_m2m_ioctl_stateless_decoder_cmd(struct file *file, void *priv,
+					 struct v4l2_decoder_cmd *dc);
 int v4l2_m2m_fop_mmap(struct file *file, struct vm_area_struct *vma);
 __poll_t v4l2_m2m_fop_poll(struct file *file, poll_table *wait);
 
-- 
2.23.0