[media] videobuf2-core: add helper functions

Add helper functions to make it easier to adapt drivers to vb2.

These helpers take care of core locking and check if the filehandle is the
owner of the queue.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

1 files changed, 41 insertions, 0 deletions

diff --git a/include/media/videobuf2-core.h b/include/media/videobuf2-core.h
index 924e95e0a0a6..8dd9b6cc296b 100644
--- a/include/media/videobuf2-core.h
+++ b/include/media/videobuf2-core.h
@@ -417,4 +417,45 @@ vb2_plane_size(struct vb2_buffer *vb, unsigned int plane_no)
         return 0;
 }
 
+/*
+ * The following functions are not part of the vb2 core API, but are simple
+ * helper functions that you can use in your struct v4l2_file_operations,
+ * struct v4l2_ioctl_ops and struct vb2_ops. They will serialize if vb2_queue->lock
+ * or video_device->lock is set, and they will set and test vb2_queue->owner
+ * to check if the calling filehandle is permitted to do the queuing operation.
+ */
+
+/* struct v4l2_ioctl_ops helpers */
+
+int vb2_ioctl_reqbufs(struct file *file, void *priv,
+                          struct v4l2_requestbuffers *p);
+int vb2_ioctl_create_bufs(struct file *file, void *priv,
+                          struct v4l2_create_buffers *p);
+int vb2_ioctl_prepare_buf(struct file *file, void *priv,
+                          struct v4l2_buffer *p);
+int vb2_ioctl_querybuf(struct file *file, void *priv, struct v4l2_buffer *p);
+int vb2_ioctl_qbuf(struct file *file, void *priv, struct v4l2_buffer *p);
+int vb2_ioctl_dqbuf(struct file *file, void *priv, struct v4l2_buffer *p);
+int vb2_ioctl_streamon(struct file *file, void *priv, enum v4l2_buf_type i);
+int vb2_ioctl_streamoff(struct file *file, void *priv, enum v4l2_buf_type i);
+
+/* struct v4l2_file_operations helpers */
+
+int vb2_fop_mmap(struct file *file, struct vm_area_struct *vma);
+int vb2_fop_release(struct file *file);
+ssize_t vb2_fop_write(struct file *file, char __user *buf,
+                size_t count, loff_t *ppos);
+ssize_t vb2_fop_read(struct file *file, char __user *buf,
+                size_t count, loff_t *ppos);
+unsigned int vb2_fop_poll(struct file *file, poll_table *wait);
+#ifndef CONFIG_MMU
+unsigned long vb2_fop_get_unmapped_area(struct file *file, unsigned long addr,
+                unsigned long len, unsigned long pgoff, unsigned long flags);
+#endif
+
+/* struct vb2_ops helpers, only use if vq->lock is non-NULL. */
+
+void vb2_ops_wait_prepare(struct vb2_queue *vq);
+void vb2_ops_wait_finish(struct vb2_queue *vq);
+
 #endif /* _MEDIA_VIDEOBUF2_CORE_H */