[media] V4L: Add mem2mem ioctl and file operation helpers

This patch adds ioctl helpers to the V4L2 mem-to-mem API, so we can avoid
several ioctl handlers in the mem-to-mem video node drivers that are simply
a pass-through to the v4l2_m2m_* calls. These helpers will only be useful
for drivers that use same mutex for both OUTPUT and CAPTURE queue, which
is the case for all currently in tree v4l2 m2m drivers. In order to use
the helpers the drivers are required to use struct v4l2_fh.

Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

2 files changed, 28 insertions, 0 deletions

diff --git a/include/media/v4l2-fh.h b/include/media/v4l2-fh.h
index 528cdaf622e1..803516775162 100644
--- a/include/media/v4l2-fh.h
+++ b/include/media/v4l2-fh.h
@@ -45,6 +45,10 @@ struct v4l2_fh {
         struct list_head        available; /* Dequeueable event */
         unsigned int            navailable;
         u32                     sequence;
+
+#if IS_ENABLED(CONFIG_V4L2_MEM2MEM_DEV)
+        struct v4l2_m2m_ctx     *m2m_ctx;
+#endif
 };
 
 /*
diff --git a/include/media/v4l2-mem2mem.h b/include/media/v4l2-mem2mem.h
index 44542a20ab81..12ea5a6a4331 100644
--- a/include/media/v4l2-mem2mem.h
+++ b/include/media/v4l2-mem2mem.h
@@ -64,6 +64,9 @@ struct v4l2_m2m_queue_ctx {
 };
 
 struct v4l2_m2m_ctx {
+        /* optional cap/out vb2 queues lock */
+        struct mutex                    *q_lock;
+
 /* private: internal use only */
         struct v4l2_m2m_dev             *m2m_dev;
 
@@ -229,5 +232,26 @@ static inline void *v4l2_m2m_dst_buf_remove(struct v4l2_m2m_ctx *m2m_ctx)
         return v4l2_m2m_buf_remove(&m2m_ctx->cap_q_ctx);
 }
 
+/* v4l2 ioctl helpers */
+
+int v4l2_m2m_ioctl_reqbufs(struct file *file, void *priv,
+                                struct v4l2_requestbuffers *rb);
+int v4l2_m2m_ioctl_create_bufs(struct file *file, void *fh,
+                                struct v4l2_create_buffers *create);
+int v4l2_m2m_ioctl_querybuf(struct file *file, void *fh,
+                                struct v4l2_buffer *buf);
+int v4l2_m2m_ioctl_expbuf(struct file *file, void *fh,
+                                struct v4l2_exportbuffer *eb);
+int v4l2_m2m_ioctl_qbuf(struct file *file, void *fh,
+                                struct v4l2_buffer *buf);
+int v4l2_m2m_ioctl_dqbuf(struct file *file, void *fh,
+                                struct v4l2_buffer *buf);
+int v4l2_m2m_ioctl_streamon(struct file *file, void *fh,
+                                enum v4l2_buf_type type);
+int v4l2_m2m_ioctl_streamoff(struct file *file, void *fh,
+                                enum v4l2_buf_type type);
+int v4l2_m2m_fop_mmap(struct file *file, struct vm_area_struct *vma);
+unsigned int v4l2_m2m_fop_poll(struct file *file, poll_table *wait);
+
 #endif /* _MEDIA_V4L2_MEM2MEM_H */