[PATCH v5 01/22] v4l2-ctrls: add v4l2_ctrl_request_hdl_find/put/ctrl_find functions

Paul Kocialkowski
2018-07-10T08:00:53Z

From: Hans Verkuil <hverkuil-qWit8jRvyhVmR6Xm/wNWPw@public.gmane.org>

If a driver needs to find/inspect the controls set in a request then
it can use these functions.

E.g. to check if a required control is set in a request use this in the
req_validate() implementation:

int res = -EINVAL;

hdl = v4l2_ctrl_request_hdl_find(req, parent_hdl);
if (hdl) {
if (v4l2_ctrl_request_hdl_ctrl_find(hdl, ctrl_id))
res = 0;
v4l2_ctrl_request_hdl_put(hdl);
}
return res;

Signed-off-by: Hans Verkuil <hans.verkuil-FYB4Gu1CFyUAvxtiuMwx3w@public.gmane.org>
---
drivers/media/v4l2-core/v4l2-ctrls.c | 25 ++++++++++++++++
include/media/v4l2-ctrls.h | 44 +++++++++++++++++++++++++++-
2 files changed, 68 insertions(+), 1 deletion(-)

diff --git a/drivers/media/v4l2-core/v4l2-ctrls.c b/drivers/media/v4l2-core/v4l2-ctrls.c
index 86a6ae54ccaa..198b7e924d21 100644
--- a/drivers/media/v4l2-core/v4l2-ctrls.c
+++ b/drivers/media/v4l2-core/v4l2-ctrls.c
@@ -2976,6 +2976,31 @@ static const struct media_request_object_ops req_ops = {
.release = v4l2_ctrl_request_release,
};

+struct v4l2_ctrl_handler *v4l2_ctrl_request_hdl_find(struct media_request *req,
+ struct v4l2_ctrl_handler *parent)
+{
+ struct media_request_object *obj;
+
+ if (WARN_ON(req->state != MEDIA_REQUEST_STATE_VALIDATING &&
+ req->state != MEDIA_REQUEST_STATE_QUEUED))
+ return NULL;
+
+ obj = media_request_object_find(req, &req_ops, parent);
+ if (obj)
+ return container_of(obj, struct v4l2_ctrl_handler, req_obj);
+ return NULL;
+}
+EXPORT_SYMBOL_GPL(v4l2_ctrl_request_hdl_find);
+
+struct v4l2_ctrl *
+v4l2_ctrl_request_hdl_ctrl_find(struct v4l2_ctrl_handler *hdl, u32 id)
+{
+ struct v4l2_ctrl_ref *ref = find_ref_lock(hdl, id);
+
+ return (ref && ref->req == ref) ? ref : NULL;
+}
+EXPORT_SYMBOL_GPL(v4l2_ctrl_request_hdl_ctrl_find);
+
static int v4l2_ctrl_request_bind(struct media_request *req,
struct v4l2_ctrl_handler *hdl,
struct v4l2_ctrl_handler *from)
diff --git a/include/media/v4l2-ctrls.h b/include/media/v4l2-ctrls.h
index de70cc3a1b80..34ee3167d7dd 100644
--- a/include/media/v4l2-ctrls.h
+++ b/include/media/v4l2-ctrls.h
@@ -1111,7 +1111,49 @@ void v4l2_ctrl_request_setup(struct media_request *req,
* request object.
*/
void v4l2_ctrl_request_complete(struct media_request *req,
- struct v4l2_ctrl_handler *hdl);
+ struct v4l2_ctrl_handler *parent);
+
+/**
+ * v4l2_ctrl_request_hdl_find - Find the control handler in the request
+ *
+ * @req: The request
+ * @parent: The parent control handler ('priv' in media_request_object_find())
+ *
+ * This function finds the control handler in the request. It may return
+ * NULL if not found. When done, you must call v4l2_ctrl_request_put_hdl()
+ * with the returned handler pointer.
+ *
+ * If the request is not in state VALIDATING or QUEUED, then this function
+ * will always return NULL.
+ */
+struct v4l2_ctrl_handler *v4l2_ctrl_request_hdl_find(struct media_request *req,
+ struct v4l2_ctrl_handler *parent);
+
+/**
+ * v4l2_ctrl_request_hdl_put - Put the control handler
+ *
+ * @hdl: Put this control handler
+ *
+ * This function released the control handler previously obtained from'
+ * v4l2_ctrl_request_hdl_find().
+ */
+static inline void v4l2_ctrl_request_hdl_put(struct v4l2_ctrl_handler *hdl)
+{
+ if (hdl)
+ media_request_object_put(&hdl->req_obj);
+}
+
+/**
+ * v4l2_ctrl_request_ctrl_find() - Find a control with the given ID.
+ *
+ * @hdl: The control handler from the request.
+ * @id: The ID of the control to find.
+ *
+ * This function returns a pointer to the control if this control is
+ * part of the request or NULL otherwise.
+ */
+struct v4l2_ctrl *
+v4l2_ctrl_request_hdl_ctrl_find(struct v4l2_ctrl_handler *hdl, u32 id);

/* Helpers for ioctl_ops */

--
2.17.1