Re: [PATCH] v4l2-ctrls: add v4l2_ctrl_request_hdl_find/put/ctrl_find functions
Hi,
On Wed, 2018-07-04 at 17:38 +0200, Hans Verkuil wrote:
> 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;
Thanks again for pulling this off, that's definitely what I neeeded!
I was able to test the patch and get it to work with sunxi-cedrus, with
one modification highlighted below.
Note that for my use case, I need to have access to the driver's private
data (context) to get the parent hdl. I'm iterating over request objects
and getting the context from a buffer object (checked via
vb2_request_object_is_buffer), a bit like it's done in
vb2_m2m_request_queue.
> Signed-off-by: Hans Verkuil
> ---
> Paul, please test this. This should be what you need.
>
> Regards,
>
> Hans
> ---
> diff --git a/drivers/media/v4l2-core/v4l2-ctrls.c
> b/drivers/media/v4l2-core/v4l2-ctrls.c
> index 3ff17c87b3c8..03fd140736fd 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, _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;
When req && ref->req == ref, ref->ctrl should be returned instead of
ref.
Cheers,
Paul
--
Paul Kocialkowski, Bootlin (formerly Free Electrons)
Embedded Linux and kernel engineering
https://bootlin.com
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[PATCH] v4l2-ctrls: add v4l2_ctrl_request_hdl_find/put/ctrl_find functions
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
---
Paul, please test this. This should be what you need.
Regards,
Hans
---
diff --git a/drivers/media/v4l2-core/v4l2-ctrls.c
b/drivers/media/v4l2-core/v4l2-ctrls.c
index 3ff17c87b3c8..03fd140736fd 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, _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
@@ -,7 +,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(>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 */
